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Ataman LM, Laronda MM, Gowett M, Trotter K, Anvari H, Fei F, Ingram A, Minette M, Suebthawinkul C, Taghvaei Z, Torres-Vélez M, Velez K, Adiga SK, Anazodo A, Appiah L, Bourlon MT, Daniels N, Dolmans MM, Finlayson C, Gilchrist RB, Gomez-Lobo V, Greenblatt E, Halpern JA, Hutt K, Johnson EK, Kawamura K, Khrouf M, Kimelman D, Kristensen S, Mitchell RT, Moravek MB, Nahata L, Orwig KE, Pavone ME, Pépin D, Pesce R, Quinn GP, Rosen MP, Rowell E, Smith K, Venter C, Whiteside S, Xiao S, Zelinski M, Goldman KN, Woodruff TK, Duncan FE. A synopsis of global frontiers in fertility preservation. J Assist Reprod Genet 2022; 39:1693-1712. [PMID: 35870095 PMCID: PMC9307970 DOI: 10.1007/s10815-022-02570-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 07/08/2022] [Indexed: 11/28/2022] Open
Abstract
Since 2007, the Oncofertility Consortium Annual Conference has brought together a diverse network of individuals from a wide range of backgrounds and professional levels to disseminate emerging basic and clinical research findings in fertility preservation. This network also developed enduring educational materials to accelerate the pace and quality of field-wide scientific communication. Between 2007 and 2019, the Oncofertility Consortium Annual Conference was held as an in-person event in Chicago, IL. The conference attracted approximately 250 attendees each year representing 20 countries around the world. In 2020, however, the COVID-19 pandemic disrupted this paradigm and precluded an in-person meeting. Nevertheless, there remained an undeniable demand for the oncofertility community to convene. To maintain the momentum of the field, the Oncofertility Consortium hosted a day-long virtual meeting on March 5, 2021, with the theme of "Oncofertility Around the Globe" to highlight the diversity of clinical care and translational research that is ongoing around the world in this discipline. This virtual meeting was hosted using the vFairs ® conference platform and allowed over 700 people to participate, many of whom were first-time conference attendees. The agenda featured concurrent sessions from presenters in six continents which provided attendees a complete overview of the field and furthered our mission to create a global community of oncofertility practice. This paper provides a synopsis of talks delivered at this event and highlights the new advances and frontiers in the fields of oncofertility and fertility preservation around the globe from clinical practice and patient-centered efforts to translational research.
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Affiliation(s)
- L M Ataman
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 7-117, Chicago, IL, 60611, USA
| | - M M Laronda
- Stanley Manne Children's Research Institute, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, USA
- Department of Pediatrics, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - M Gowett
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 7-117, Chicago, IL, 60611, USA
| | - K Trotter
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 7-117, Chicago, IL, 60611, USA
| | - H Anvari
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 7-117, Chicago, IL, 60611, USA
| | - F Fei
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 7-117, Chicago, IL, 60611, USA
| | - A Ingram
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 7-117, Chicago, IL, 60611, USA
| | - M Minette
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 7-117, Chicago, IL, 60611, USA
| | - C Suebthawinkul
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 7-117, Chicago, IL, 60611, USA
| | - Z Taghvaei
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 7-117, Chicago, IL, 60611, USA
| | - M Torres-Vélez
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 7-117, Chicago, IL, 60611, USA
| | - K Velez
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 7-117, Chicago, IL, 60611, USA
| | - S K Adiga
- Department of Clinical Embryology, Kasturba Medical College Manipal, Manipal Academy of Higher Education, Manipal, India
| | - A Anazodo
- Kids Cancer Centre, Sydney Children's Hospital, Nelune Comprehensive Cancer Centre, Sydney, Australia
- School of Clinical Medicine, University of New South Wales, Sydney, Australia
| | - L Appiah
- Department of Obstetrics and Gynecology, The University of Colorado School of Medicine, Aurora, CO, USA
| | - M T Bourlon
- Hemato-Oncology Department, Instituto Nacional de Ciencias Médicas Y Nutrición Salvador Zubirán, Mexico City, Mexico
| | - N Daniels
- The Oncology and Fertility Centres of Ekocorp, Eko Hospitals, Lagos, Nigeria
| | - M M Dolmans
- Gynecology Research Unit, Institut de Recherche Expérimentale Et Clinique, Université Catholique de Louvain, Av. Mounier 52, 1200, Brussels, Belgium
- Department of Gynecology, Cliniques Universitaires Saint-Luc, Av. Hippocrate 10, 1200, Brussels, Belgium
| | - C Finlayson
- Department of Pediatrics (Endocrinology), Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - R B Gilchrist
- School of Clinical Medicine, University of New South Wales, Sydney, Australia
| | - V Gomez-Lobo
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | | | - J A Halpern
- Department of Urology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - K Hutt
- Anatomy & Developmental Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Australia
| | - E K Johnson
- Department of Urology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
- Division of Urology, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, USA
| | - K Kawamura
- Department of Obstetrics and Gynecology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - M Khrouf
- FERTILLIA, Clinique la Rose, Tunis, Tunisia
| | - D Kimelman
- Centro de Esterilidad Montevideo, Montevideo, Uruguay
| | - S Kristensen
- Department of Fertility, Copenhagen University Hospital, Copenhagen, Denmark
| | - R T Mitchell
- Department of Developmental Endocrinology, University of Edinburgh, Edinburgh, UK
| | - M B Moravek
- Department of Obstetrics and Gynecology, Division of Reproductive Endocrinology and Infertility, University of Michigan, Ann Arbor, MI, USA
- Department of Urology, University of Michigan, Ann Arbor, MI, USA
| | - L Nahata
- Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH, USA
- Endocrinology and Center for Biobehavioral Health, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, USA
| | - K E Orwig
- Department of Obstetrics, Gynecology and Reproductive Sciences, Magee-Womens Research Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - M E Pavone
- Department of Obstetrics and Gynecology, Reproductive Endocrinology and Infertility, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - D Pépin
- Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - R Pesce
- Reproductive Medicine Unit, Obstetrics and Gynecology Department, Hospital Italiano de Buenos Aires, Buenos Aires, Argentina
| | - G P Quinn
- Departments of Obstetrics and Gynecology, Center for Medical Ethics, Population Health, Grossman School of Medicine, New York University, New York, NY, USA
| | - M P Rosen
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Division of Reproductive Endocrinology and Infertility, University of California, San Francisco, CA, USA
| | - E Rowell
- Department of Surgery (Pediatric Surgery), Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - K Smith
- Department of Obstetrics and Gynecology, Reproductive Endocrinology and Infertility, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - C Venter
- Vitalab, Johannesburg, South Africa
| | - S Whiteside
- Fertility & Reproductive Health Program, Department of Hematology/Oncology/BMT, Nationwide Children's Hospital, Columbus, OH, USA
| | - S Xiao
- Department of Pharmacology and Toxicology, Ernest Mario School of Pharmacy, Environmental Health Sciences Institute, Rutgers University, New Brunswick, NJ, USA
| | - M Zelinski
- Division of Reproductive & Developmental Sciences, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR, USA
| | - K N Goldman
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 7-117, Chicago, IL, 60611, USA
| | - T K Woodruff
- Department of Obstetrics, Gynecology, and Reproductive Biology, College of Human Medicine, Michigan State University, East Lansing, MI, USA
| | - F E Duncan
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 7-117, Chicago, IL, 60611, USA.
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Ataman LM, Laronda MM, Gowett M, Trotter K, Anvari H, Fei F, Ingram A, Minette M, Suebthawinkul C, Taghvaei Z, Torres-Vélez M, Velez K, Adiga SK, Anazodo A, Appiah L, Bourlon MT, Daniels N, Dolmans MM, Finlayson C, Gilchrist RB, Gomez-Lobo V, Greenblatt E, Halpern JA, Hutt K, Johnson EK, Kawamura K, Khrouf M, Kimelman D, Kristensen S, Mitchell RT, Moravek MB, Nahata L, Orwig KE, Pavone ME, Pépin D, Pesce R, Quinn GP, Rosen MP, Rowell E, Smith K, Venter C, Whiteside S, Xiao S, Zelinski M, Goldman KN, Woodruff TK, Duncan FE. Correction to: A synopsis of global frontiers in fertility preservation. J Assist Reprod Genet 2022; 39:1713-1714. [PMID: 35920992 PMCID: PMC9428069 DOI: 10.1007/s10815-022-02586-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 07/08/2022] [Indexed: 10/16/2022] Open
Affiliation(s)
- L M Ataman
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 7‑117, Chicago, IL, 60611, USA
| | - M M Laronda
- Stanley Manne Children's Research Institute, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, USA
- Department of Pediatrics, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - M Gowett
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 7‑117, Chicago, IL, 60611, USA
| | - K Trotter
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 7‑117, Chicago, IL, 60611, USA
| | - H Anvari
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 7‑117, Chicago, IL, 60611, USA
| | - F Fei
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 7‑117, Chicago, IL, 60611, USA
| | - A Ingram
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 7‑117, Chicago, IL, 60611, USA
| | - M Minette
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 7‑117, Chicago, IL, 60611, USA
| | - C Suebthawinkul
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 7‑117, Chicago, IL, 60611, USA
| | - Z Taghvaei
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 7‑117, Chicago, IL, 60611, USA
| | - M Torres-Vélez
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 7‑117, Chicago, IL, 60611, USA
| | - K Velez
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 7‑117, Chicago, IL, 60611, USA
| | - S K Adiga
- Department of Clinical Embryology, Kasturba Medical College Manipal, Manipal Academy of Higher Education, Manipal, India
| | - A Anazodo
- Kids Cancer Centre, Sydney Children's Hospital, Nelune Comprehensive Cancer Centre, Sydney, Australia
- School of Clinical Medicine, University of New South Wales, Sydney, Australia
| | - L Appiah
- Department of Obstetrics and Gynecology, The University of Colorado School of Medicine, Aurora, CO, USA
| | - M T Bourlon
- Hemato‑Oncology Department, Instituto Nacional de Ciencias Médicas Y Nutrición Salvador Zubirán, Mexico City, Mexico
| | - N Daniels
- The Oncology and Fertility Centres of Ekocorp, Eko Hospitals, Lagos, Nigeria
| | - M M Dolmans
- Gynecology Research Unit, Institut de Recherche Expérimentale Et Clinique, Université Catholique de Louvain, Av. Mounier 52, 1200, Brussels, Belgium
- Department of Gynecology, Cliniques Universitaires Saint-Luc, Av. Hippocrate 10, 1200, Brussels, Belgium
| | - C Finlayson
- Department of Pediatrics (Endocrinology), Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - R B Gilchrist
- School of Clinical Medicine, University of New South Wales, Sydney, Australia
| | - V Gomez-Lobo
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | | | - J A Halpern
- Department of Urology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - K Hutt
- Anatomy & Developmental Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Australia
| | - E K Johnson
- Department of Urology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
- Division of Urology, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, USA
| | - K Kawamura
- Department of Obstetrics and Gynecology, Juntendo University Faculty of Medicine, Tokyo, Japan
| | - M Khrouf
- FERTILLIA, Clinique la Rose, Tunis, Tunisia
| | - D Kimelman
- Centro de Esterilidad Montevideo, Montevideo, Uruguay
| | - S Kristensen
- Department of Fertility, Copenhagen University Hospital, Copenhagen, Denmark
| | - R T Mitchell
- Department of Developmental Endocrinology, University of Edinburgh, Edinburgh, UK
| | - M B Moravek
- Department of Obstetrics and Gynecology, Division of Reproductive Endocrinology and Infertility, University of Michigan, Ann Arbor, MI, USA
- Department of Urology, University of Michigan, Ann Arbor, MI, USA
| | - L Nahata
- Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH, USA
- Endocrinology and Center for Biobehavioral Health, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, USA
| | - K E Orwig
- Department of Obstetrics, Gynecology and Reproductive Sciences, Magee-Womens Research Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - M E Pavone
- Department of Obstetrics and Gynecology, Reproductive Endocrinology and Infertility, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - D Pépin
- Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - R Pesce
- Reproductive Medicine Unit, Obstetrics and Gynecology Department, Hospital Italiano de Buenos Aires, Buenos Aires, Argentina
| | - G P Quinn
- Departments of Obstetrics and Gynecology, Center for Medical Ethics, Population Health, Grossman School of Medicine, New York University, New York, NY, USA
| | - M P Rosen
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Division of Reproductive Endocrinology and Infertility, University of California, San Francisco, CA, USA
| | - E Rowell
- Department of Surgery (Pediatric Surgery), Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - K Smith
- Department of Obstetrics and Gynecology, Reproductive Endocrinology and Infertility, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - C Venter
- Vitalab, Johannesburg, South Africa
| | - S Whiteside
- Fertility & Reproductive Health Program, Department of Hematology/Oncology/BMT, Nationwide Children's Hospital, Columbus, OH, USA
| | - S Xiao
- Department of Pharmacology and Toxicology, Ernest Mario School of Pharmacy, Environmental Health Sciences Institute, Rutgers University, New Brunswick, NJ, USA
| | - M Zelinski
- Division of Reproductive & Developmental Sciences, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR, USA
| | - K N Goldman
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 7‑117, Chicago, IL, 60611, USA
| | - T K Woodruff
- Department of Obstetrics, Gynecology, and Reproductive Biology, College of Human Medicine, Michigan State University, East Lansing, MI, USA
| | - F E Duncan
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Lurie 7‑117, Chicago, IL, 60611, USA.
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Matilionyte G, Tharmalingam MD, Sanou I, Lopes F, Anderson RA, Mitchell RT. O-190 Comparison between effects of exposure to platinum-based chemotherapeutics (cisplatin and carboplatin) on Sertoli cell number and functions in immature human testicular tissues. Hum Reprod 2021. [DOI: 10.1093/humrep/deab127.091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Study question
Does exposure to either cisplatin or carboplatin have a damaging effect on the Sertoli cell population in the immature human testicular tissues?
Summary answer
Exposure to cisplatin or carboplatin did not appear to have a major effect on Sertoli cell number or function in the immature human testicular tissues
What is known already
Long-term survival rates for children with cancer are more than 80%. However, childhood cancer treatment may result in subsequent infertility. Cisplatin is one of the most commonly used drugs for childhood cancers. Carboplatin, a second generation platinum drug, is administered at 10-times the dose of cisplatin and is believed to be less gonadotoxic. In our recent publication we have shown that exposure to both cisplatin and carboplatin acutely reduce the germ cell number in immature human testicular tissues. However, it is not known how cisplatin and carboplatin affect Sertoli cell number and function.
Study design, size, duration
In-vitro culture of human fetal and pre-pubertal testicular tissues was utilised. Tissue pieces were cultured for 1-3 days prior to exposure to clinically-relevant doses of chemotherapeutics or vehicle control for 24hrs in two sets of experiments: 1) 0.5 or 1 μg/ml cisplatin and culture ended at 24 and 96hrs post-exposure (fetal only); 2) 0.5 μg/ml cisplatin or 5 μg/ml carboplatin until 72 (both fetal and pre-pubertal) and 240hrs post-exposure (fetal only).
Participants/materials, setting, methods
Testicular tissue fragments from second trimester human fetal (14-22 gestational weeks; n = 3-6) or pre-pubertal patients (1-8years old; n = 5) were cultured in a ‘hanging drop’ system.Quantification of Sertoli cell number (cells per cord/tubular area (mm2)) was performed on sections stained for expression of SOX9. Culture medium was collected to measure levels (ng/ml) of Anti-Mullerian hormone (AMH) and Inhibin B using ELISA. Statistical analysis was performed using two-way ANOVA to account for inter-individual variation between fetuses/patients.
Main results and the role of chance
Quantification of positively stained Sertoli cells showed that exposure to both doses of cisplatin had no effect on Sertoli cell number at 24 and 96hrs post-exposure. No changes in AMH and inhibin B levels were observed at these time-points. Comparison between cisplatin- or carboplatin-exposed human fetal testicular tissues showed no difference in Sertoli cell numbers at either 72hrs or 240hrs post-exposure. No difference in Sertoli cell number was observed in pre-pubertal testicular tissues exposed to either cisplatin or carboplatin at 72hrs post-exposure.
Limitations, reasons for caution
Human fetal and pre-pubertal testis tissue is of limited availability, thus, sample sizes used in this study were relatively low. ‘Hanging drop’ culture might not recapitulate all in-vivo aspects of immature testis microenvironment.
Wider implications of the findings
Exposure to cisplatin or carboplatin did not affect Sertoli cell number in the immature human testicular tissues. Taken together with our recent publication, this suggests that these two platinum-based chemotherapeutic agents cause direct damage to germ cells. Functionality of Sertoli cells in chemotherapy-exposed tissues need to be further investigated.
Trial registration number
not applicable
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Affiliation(s)
- G Matilionyte
- The University of Edinburgh, Centre for Reproductive Health, Edinburgh, United Kingdom
| | - M D Tharmalingam
- The University of Edinburgh, Centre for Reproductive Health, Edinburgh, United Kingdom
| | - I Sanou
- The University of Edinburgh, Centre for Reproductive Health, Edinburgh, United Kingdom
| | - F Lopes
- The University of Edinburgh, Centre for Reproductive Health, Edinburgh, United Kingdom
| | - R A Anderson
- The University of Edinburgh, Centre for Reproductive Health, Edinburgh, United Kingdom
| | - R T Mitchell
- The University of Edinburgh, Centre for Reproductive Health, Edinburgh, United Kingdom
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Zafeiri A, Raja EA, Hay DC, Mitchell RT, Bhattacharya S, Fowler PA. P–732 Maternal over-the-counter analgesics use during pregnancy and adverse perinatal outcomes: cohort study of 151,141 singleton pregnancies. Hum Reprod 2021. [DOI: 10.1093/humrep/deab130.731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Study question
Is in utero exposure to five over-the-counter (non-prescription) analgesics (paracetamol, ibuprofen, aspirin, diclofenac, naproxen) associated with offspring health outcomes?
Summary answer
Consumption of over-the-counter analgesics during pregnancy, either as single compounds or in combinations, is significantly associated with a variety of adverse offspring health outcomes.
What is known already
A high percentage of pregnant women use over-the-counter analgesics during pregnancy globally. Some of these compounds such as paracetamol are considered safe to use, while contraindications exist for others, such as NSAIDs use beyond gestational week 30. Current evidence regarding the safety of use during pregnancy in humans is largely conflicting. Results from many published human studies on the topic suffer from limitations including use of small cohorts, short study time or failure to adjust for important confounders. These may explain conflicting results that cause significant concern regarding evidence-based prenatal guidance on use during pregnancy.
Study design, size, duration
Retrospective cohort study using the Aberdeen Maternity and Neonatal Databank. Data from 151,141 singleton pregnancies over 30 years (between 1985 and 2015) were used. Consumption of paracetamol, ibuprofen, aspirin, diclofenac and naproxen during pregnancy was recorded in medical notes of each woman. In our analysis, the control group was pregnancies where no analgesic was consumed, and the exposure groups included pregnancies with over-the-counter analgesic consumption either in combinations or as single compound use.
Participants/materials, setting, methods
Maternal baseline characteristics were compared using χ2 tests for categorical variables and Mann-Whitney for continuous variables (significance at < 0.05). Premature delivery, stillbirth, neonatal death, baby weight, neonatal unit admission, APGAR score at 1 and 5 minutes, neural tube defects, amniotic band defects, gastroschisis, and, in males only, hypospadias and cryptorchidism, were the outcomes assessed. Crude (cORs) and adjusted odds ratios (aORs) with 95% confidence intervals (CIs) were calculated using logistic regression to control for confounders.
Main results and the role of chance
The overall prevalence of over-the-counter analgesics use during pregnancy was 29.1%, increasing over the 30-year study period, to over 60% of women in the last seven years of the study. 83.7% of those women reported first trimester use when specifically asked at their first antenatal clinic visit. Pregnancies exposed to at least one of the five analgesics were independently associated with increased risks for premature delivery <37 weeks (aOR=1.50, 95%CI 1.43–1.58), stillbirth (aOR=1.33, 95%CI 1.15–1.54), neonatal death (aOR=1.56, 95%CI 1.27–1.93), birthweight <2,500g (aOR=1.28, 95%CI 1.20–1.37), birthweight >4,000g (aOR=1.09, 95%CI 1.05–1.13), admission to neonatal unit (aOR=1.57, 95%CI 1.51–1.64), APGAR score <7 at 1 minute (aOR=1.18, 95%CI 1.13–1.23) and 5 minutes (aOR=1.48, 95%CI 1.35–1.62), neural tube defects (aOR=1.64, 95%CI 1.08–2.47) and hypospadias (aOR=1.27, 95%CI 1.05–1.54 males only). ). Associations of paracetamol alone with high birth weight, neural tube defects and hypospadias were not significant in the adjusted analysis. Diclofenac consumption was associated with significantly decreased odds of stillbirth (aOR=0.59, 95%CI 0.41–0.87).
Limitations, reasons for caution
Our data were based on medical notes; however, consumption is self-reported, and details on the timing, dosage, product type (single-ingredient vs combination) and administration type were not available in the database. Our study only considered neonatal health outcomes and longer-term follow-up of the offspring was not available at this time.
Wider implications of the findings: This is one of the largest and most comprehensive studies into analgesic use in pregnancy. The increased risks of adverse neonatal outcomes associated with non-prescribed, over-the-counter, analgesics use during pregnancy indicate that healthcare guidance for pregnant women regarding analgesic use should be re-assessed.
Trial registration number
N/A
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Affiliation(s)
- A Zafeiri
- University of Aberdeen, School of Medicine- Medical Sciences and Nutrition, Aberdeen, United Kingdom
| | - E A Raja
- University of Aberdeen, School of Medicine- Medical Sciences and Nutrition, Aberdeen, United Kingdom
| | - D C Hay
- University of Edinburgh, Centre for Regenerative Medicine, Edinburgh, United Kingdom
| | - R T Mitchell
- University of Edinburgh, The Queen’s Medical Research Institute, Edinburgh, United Kingdom
| | - S Bhattacharya
- University of Aberdeen, School of Medicine- Medical Sciences and Nutrition, Aberdeen, United Kingdom
| | - P A Fowler
- University of Aberdeen, School of Medicine- Medical Sciences and Nutrition, Aberdeen, United Kingdom
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5
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Harpelunde Poulsen K, Nielsen JE, Frederiksen H, Melau C, Juul Hare K, Langhoff Thuesen L, Perlman S, Lundvall L, Mitchell RT, Juul A, Rajpert-De Meyts E, Jørgensen A. Dysregulation of FGFR signalling by a selective inhibitor reduces germ cell survival in human fetal gonads of both sexes and alters the somatic niche in fetal testes. Hum Reprod 2020; 34:2228-2243. [PMID: 31734698 PMCID: PMC6994936 DOI: 10.1093/humrep/dez191] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 08/08/2019] [Indexed: 01/03/2023] Open
Abstract
STUDY QUESTION Does experimental manipulation of fibroblast growth factor 9 (FGF9)-signalling in human fetal gonads alter sex-specific gonadal differentiation? SUMMARY ANSWER Inhibition of FGFR signalling following SU5402 treatment impaired germ cell survival in both sexes and severely altered the developing somatic niche in testes, while stimulation of FGF9 signalling promoted Sertoli cell proliferation in testes and inhibited meiotic entry of germ cells in ovaries. WHAT IS KNOWN ALREADY Sex-specific differentiation of bipotential gonads involves a complex signalling cascade that includes a combination of factors promoting either testicular or ovarian differentiation and inhibition of the opposing pathway. In mice, FGF9/FGFR2 signalling has been shown to promote testicular differentiation and antagonize the female developmental pathway through inhibition of WNT4. STUDY DESIGN, SIZE, DURATION FGF signalling was manipulated in human fetal gonads in an established ex vivo culture model by treatments with recombinant FGF9 (25 ng/ml) and the tyrosine kinase inhibitor SU5402 (10 μM) that was used to inhibit FGFR signalling. Human fetal testis and ovary tissues were cultured for 14 days and effects on gonadal development and expression of cell lineage markers were determined. PARTICIPANTS/MATERIALS, SETTING, METHODS Gonadal tissues from 44 male and 33 female embryos/fetuses from first trimester were used for ex vivo culture experiments. Tissues were analyzed by evaluation of histology and immunohistochemical analysis of markers for germ cells, somatic cells, proliferation and apoptosis. Culture media were collected throughout the experimental period and production of steroid hormone metabolites was analyzed in media from fetal testis cultures by liquid chromatography-tandem mass spectrometry (LC-MS/MS). MAIN RESULTS AND THE ROLE OF CHANCE Treatment with SU5402 resulted in near complete loss of gonocytes (224 vs. 14 OCT4+ cells per mm2, P < 0.05) and oogonia (1456 vs. 28 OCT4+ cells per mm2, P < 0.001) in human fetal testes and ovaries, respectively. This was a result of both increased apoptosis and reduced proliferation in the germ cells. Addition of exogenous FGF9 to the culture media resulted in a reduced number of germ cells entering meiosis in fetal ovaries (102 vs. 60 γH2AX+ germ cells per mm2, P < 0.05), while in fetal testes FGF9 stimulation resulted in an increased number of Sertoli cells (2503 vs. 3872 SOX9+ cells per mm2, P < 0.05). In fetal testes, inhibition of FGFR signalling by SU5402 treatment altered seminiferous cord morphology and reduced the AMH expression as well as the number of SOX9-positive Sertoli cells (2503 vs. 1561 SOX9+ cells per mm2, P < 0.05). In interstitial cells, reduced expression of COUP-TFII and increased expression of CYP11A1 and CYP17A1 in fetal Leydig cells was observed, although there were no subsequent changes in steroidogenesis. LARGE SCALE DATA N/A. LIMITATIONS, REASONS FOR CAUTION Ex vivo culture may not replicate all aspects of fetal gonadal development and function in vivo. Although the effects of FGF9 were studied in ex vivo culture experiments, there is no direct evidence that FGF9 acts in vivo during human fetal gonadogenesis. The FGFR inhibitor (SU5402) used in this study is not specific to FGFR2 but inhibits all FGF receptors and off-target effects on unrelated tyrosine kinases should be considered. WIDER IMPLICATIONS OF THE FINDINGS The findings of this study suggest that dysregulation of FGFR-mediated signalling may affect both testicular and ovarian development, in particular impacting the fetal germ cell populations in both sexes. STUDY FUNDING/COMPETING INTEREST(S) This work was supported in part by an ESPE Research Fellowship, sponsored by Novo Nordisk A/S to A.JØ. Additional funding was obtained from the Erichsen Family Fund (A.JØ.), the Aase and Ejnar Danielsens Fund (A.JØ.), the Danish Government's support for the EDMaRC programme (A.JU.) and a Wellcome Trust Intermediate Clinical Fellowship (R.T.M., Grant no. 098522). The Medical Research Council (MRC) Centre for Reproductive Health (R.T.M.) is supported by an MRC Centre Grant (MR/N022556/1). The authors have no conflict of interest to disclose.
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Affiliation(s)
- K Harpelunde Poulsen
- Department of Growth and Reproduction, Copenhagen University Hospital (Rigshospitalet), Blegdamsvej 9, 2100 Copenhagen, Denmark.,International Research and Research Training Centre in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), Blegdamsvej 9, 2100 Copenhagen, Denmark
| | - J E Nielsen
- Department of Growth and Reproduction, Copenhagen University Hospital (Rigshospitalet), Blegdamsvej 9, 2100 Copenhagen, Denmark.,International Research and Research Training Centre in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), Blegdamsvej 9, 2100 Copenhagen, Denmark
| | - H Frederiksen
- Department of Growth and Reproduction, Copenhagen University Hospital (Rigshospitalet), Blegdamsvej 9, 2100 Copenhagen, Denmark.,International Research and Research Training Centre in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), Blegdamsvej 9, 2100 Copenhagen, Denmark
| | - C Melau
- Department of Growth and Reproduction, Copenhagen University Hospital (Rigshospitalet), Blegdamsvej 9, 2100 Copenhagen, Denmark.,International Research and Research Training Centre in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), Blegdamsvej 9, 2100 Copenhagen, Denmark
| | - K Juul Hare
- Department of Obstetrics and Gynaecology, Hvidovre University Hospital, Kettegård Alle 30, 2650 Hvidovre, Denmark
| | - L Langhoff Thuesen
- Department of Obstetrics and Gynaecology, Hvidovre University Hospital, Kettegård Alle 30, 2650 Hvidovre, Denmark
| | - S Perlman
- Department of Gynaecology, Copenhagen University Hospital (Rigshospitalet), Blegdamsvej 9, Copenhagen 2100, Denmark
| | - L Lundvall
- Department of Gynaecology, Copenhagen University Hospital (Rigshospitalet), Blegdamsvej 9, Copenhagen 2100, Denmark
| | - R T Mitchell
- MRC Centre for Reproductive Health, The Queen's Medical Research Institute, University of Edinburgh, 47 Little France Crescent, Edinburgh EH16 4TJ, UK
| | - A Juul
- Department of Growth and Reproduction, Copenhagen University Hospital (Rigshospitalet), Blegdamsvej 9, 2100 Copenhagen, Denmark.,International Research and Research Training Centre in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), Blegdamsvej 9, 2100 Copenhagen, Denmark
| | - E Rajpert-De Meyts
- Department of Growth and Reproduction, Copenhagen University Hospital (Rigshospitalet), Blegdamsvej 9, 2100 Copenhagen, Denmark.,International Research and Research Training Centre in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), Blegdamsvej 9, 2100 Copenhagen, Denmark
| | - A Jørgensen
- Department of Growth and Reproduction, Copenhagen University Hospital (Rigshospitalet), Blegdamsvej 9, 2100 Copenhagen, Denmark.,International Research and Research Training Centre in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), Blegdamsvej 9, 2100 Copenhagen, Denmark
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Ntemou E, Kadam P, Van Saen D, Wistuba J, Mitchell RT, Schlatt S, Goossens E. Complete spermatogenesis in intratesticular testis tissue xenotransplants from immature non-human primate. Hum Reprod 2020; 34:403-413. [PMID: 30753464 PMCID: PMC6389866 DOI: 10.1093/humrep/dey373] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 11/20/2018] [Accepted: 11/30/2018] [Indexed: 11/13/2022] Open
Abstract
STUDY QUESTION Can full spermatogenesis be achieved after xenotransplantation of prepubertal primate testis tissue to the mouse, in testis or subcutaneously? SUMMARY ANSWER Intratesticular xenotransplantation supported the differentiation of immature germ cells from marmoset (Callithrix jacchus) into spermatids and spermatozoa at 4 and 9 months post-transplantation, while in subcutaneous transplants, spermatogenic arrest was observed at 4 months and none of the transplants survived at 9 months. WHAT IS KNOWN ALREADY Auto-transplantation of cryopreserved immature testis tissue (ITT) could be a potential fertility restoration strategy for patients with complete loss of germ cells due to chemo- and/or radiotherapy at a young age. Before ITT transplantation can be used for clinical application, it is a prerequisite to demonstrate the feasibility of the technique and identify the conditions required for establishing spermatogenesis in primate ITT transplants. Although xenotransplantation of ITT from several species has resulted in complete spermatogenesis, in human and marmoset, ITT has not been successful. STUDY DESIGN, SIZE, DURATION In this study, we used marmoset as a pre-clinical animal model. ITT was obtained from two 6-month-old co-twin marmosets. A total of 147 testis tissue pieces (~0.8-1.0 mm3 each) were transplanted into the testicular parenchyma (intratesticular; n = 40) or under the dorsal skin (ectopic; n = 107) of 4-week-old immunodeficient Swiss Nu/Nu mice (n = 20). Each mouse received one single marmoset testis tissue piece in each testis and 4-6 pieces subcutaneously. Xenotransplants were retrieved at 4 and 9 months post-transplantation and evaluations were performed with regards to transplant survival, spermatogonial quantity and germ cell differentiation. PARTICIPANTS/MATERIALS, SETTING, METHODS Transplant survival was histologically evaluated by haematoxylin-periodic acid Schiff (H/PAS) staining. Spermatogonia were identified by MAGE-A4 via immunohistochemistry. Germ cell differentiation was assessed by morphological identification of different germ cell types on H/PAS stained sections. Meiotically active germ cells were identified by BOLL expression. CREM immunohistochemistry was performed to confirm the presence of post-meiotic germ cells and ACROSIN was used to determine the presence of round, elongating and elongated spermatids. MAIN RESULTS AND THE ROLE OF CHANCE Four months post-transplantation, 50% of the intratesticular transplants and 21% of the ectopic transplants were recovered (P = 0.019). The number of spermatogonia per tubule did not show any variation. In 33% of the recovered intratesticular transplants, complete spermatogenesis was established. Overall, 78% of the intratesticular transplants showed post-meiotic differentiation (round spermatids, elongating/elongated spermatids and spermatozoa). However, during the same period, spermatocytes (early meiotic germ cells) were the most advanced germ cell type present in the ectopic transplants. Nine months post-transplantation, 50% of the intratesticular transplants survived, whilst none of the ectopic transplants was recovered (P < 0.0001). Transplants contained more spermatogonia per tubule (P = 0.018) than at 4 months. Complete spermatogenesis was observed in all recovered transplants (100%), indicating a progressive spermatogenic development in intratesticular transplants between the two time-points. Nine months post-transplantation, transplants contained more seminiferous tubules with post-meiotic germ cells (37 vs. 5%; P < 0.001) and fewer tubules without germ cells (2 vs. 8%; P = 0.014) compared to 4 months post-transplantation. LARGE SCALE DATA N/A. LIMITATIONS, REASONS FOR CAUTION Although xenotransplantation of marmoset ITT was successful, it does not fully reflect all aspects of a future clinical setting. Furthermore, due to ethical restrictions, we were not able to prove the functionality of the spermatozoa produced in the marmoset transplants. WIDER IMPLICATIONS OF THE FINDINGS In this pre-clinical study, we demonstrated that testicular parenchyma provides the required microenvironment for germ cell differentiation and long-term survival of immature marmoset testis tissue, likely due to the favourable temperature regulation, growth factors and hormonal support. These results encourage the design of new experiments on human ITT xenotransplantation and show that intratesticular transplantation is likely to be superior to ectopic transplantation for fertility restoration following gonadotoxic treatment in childhood. STUDY FUNDING/COMPETING INTEREST(S) This project was funded by the ITN Marie Curie Programme 'Growsperm' (EU-FP7-PEOPLE-2013-ITN 603568) and the scientific Fund Willy Gepts from the UZ Brussel (ADSI677). D.V.S. is a post-doctoral fellow of the Fonds Wetenschappelijk Onderzoek (FWO; 12M2815N). No conflict of interest is declared.
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Affiliation(s)
- E Ntemou
- Biology of the Testis Lab, Department of Reproduction, Genetics and Regenerative Medicine, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - P Kadam
- Biology of the Testis Lab, Department of Reproduction, Genetics and Regenerative Medicine, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - D Van Saen
- Biology of the Testis Lab, Department of Reproduction, Genetics and Regenerative Medicine, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - J Wistuba
- Centre of Reproductive Medicine and Andrology (CeRA), University of Münster, Münster, Germany
| | - R T Mitchell
- MRC Centre for Reproductive Health, The University of Edinburgh, The Queen's Medical Research Institute, Edinburgh, Scotland, UK.,Edinburgh Royal Hospital for Sick Children, Edinburgh, Scotland, UK
| | - S Schlatt
- Centre of Reproductive Medicine and Andrology (CeRA), University of Münster, Münster, Germany
| | - E Goossens
- Biology of the Testis Lab, Department of Reproduction, Genetics and Regenerative Medicine, Vrije Universiteit Brussel (VUB), Brussels, Belgium
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Goossens E, Jahnukainen K, Mitchell RT, van Pelt A, Pennings G, Rives N, Poels J, Wyns C, Lane S, Rodriguez-Wallberg KA, Rives A, Valli-Pulaski H, Steimer S, Kliesch S, Braye A, Andres MM, Medrano J, Ramos L, Kristensen SG, Andersen CY, Bjarnason R, Orwig KE, Neuhaus N, Stukenborg JB. Fertility preservation in boys: recent developments and new insights †. Hum Reprod Open 2020; 2020:hoaa016. [PMID: 32529047 PMCID: PMC7275639 DOI: 10.1093/hropen/hoaa016] [Citation(s) in RCA: 88] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 01/22/2020] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Infertility is an important side effect of treatments used for cancer and other non-malignant conditions in males. This may be due to the loss of spermatogonial stem cells (SSCs) and/or altered functionality of testicular somatic cells (e.g. Sertoli cells, Leydig cells). Whereas sperm cryopreservation is the first-line procedure to preserve fertility in post-pubertal males, this option does not exist for prepubertal boys. For patients unable to produce sperm and at high risk of losing their fertility, testicular tissue freezing is now proposed as an alternative experimental option to safeguard their fertility. OBJECTIVE AND RATIONALE With this review, we aim to provide an update on clinical practices and experimental methods, as well as to describe patient management inclusion strategies used to preserve and restore the fertility of prepubertal boys at high risk of fertility loss. SEARCH METHODS Based on the expertise of the participating centres and a literature search of the progress in clinical practices, patient management strategies and experimental methods used to preserve and restore the fertility of prepubertal boys at high risk of fertility loss were identified. In addition, a survey was conducted amongst European and North American centres/networks that have published papers on their testicular tissue banking activity. OUTCOMES Since the first publication on murine SSC transplantation in 1994, remarkable progress has been made towards clinical application: cryopreservation protocols for testicular tissue have been developed in animal models and are now offered to patients in clinics as a still experimental procedure. Transplantation methods have been adapted for human testis, and the efficiency and safety of the technique are being evaluated in mouse and primate models. However, important practical, medical and ethical issues must be resolved before fertility restoration can be applied in the clinic.Since the previous survey conducted in 2012, the implementation of testicular tissue cryopreservation as a means to preserve the fertility of prepubertal boys has increased. Data have been collected from 24 co-ordinating centres worldwide, which are actively offering testis tissue cryobanking to safeguard the future fertility of boys. More than 1033 young patients (age range 3 months to 18 years) have already undergone testicular tissue retrieval and storage for fertility preservation. LIMITATIONS REASONS FOR CAUTION The review does not include the data of all reproductive centres worldwide. Other centres might be offering testicular tissue cryopreservation. Therefore, the numbers might be not representative for the entire field in reproductive medicine and biology worldwide. The key ethical issue regarding fertility preservation in prepubertal boys remains the experimental nature of the intervention. WIDER IMPLICATIONS The revised procedures can be implemented by the multi-disciplinary teams offering and/or developing treatment strategies to preserve the fertility of prepubertal boys who have a high risk of fertility loss. STUDY FUNDING/COMPETING INTERESTS The work was funded by ESHRE. None of the authors has a conflict of interest.
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Affiliation(s)
- E Goossens
- Biology of the Testis, Research Laboratory for Reproduction, Genetics and Regenerative Medicine, Vrije Universiteit Brussel (VUB), 1090 Brussels, Belgium
| | - K Jahnukainen
- NORDFERTIL Research Lab Stockholm, Childhood Cancer Research Unit, Department of Women's and Children's Health, Karolinska Institutet and Karolinska University Hospital, Solna, Sweden.,Division of Haematology-Oncology and Stem Cell Transplantation, New Children's Hospital, Pediatric Research Center, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - R T Mitchell
- MRC Centre for Reproductive Health, The Queen's Medical Research Institute, The University of Edinburgh; and the Edinburgh Royal Hospital for Sick Children, Edinburgh, UK
| | - Amm van Pelt
- Center for Reproductive Medicine, Amsterdam UMC, Amsterdam Reproduction and Development Research Institute, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - G Pennings
- Bioethics Institute Ghent, Ghent University, 9000 Ghent, Belgium
| | - N Rives
- Normandie Univ, UNIROUEN, EA 4308 "Gametogenesis and Gamete Quality", Rouen University Hospital, Biology of Reproduction-CECOS Laboratory, F 76000, Rouen, France
| | - J Poels
- Department of Gynecology and Andrology, Cliniques Universitaires Saint-Luc, Université Catholique de Louvain, Brussels, Belgium
| | - C Wyns
- Department of Gynecology and Andrology, Cliniques Universitaires Saint-Luc, Université Catholique de Louvain, Brussels, Belgium
| | - S Lane
- Department of Paediatric Oncology and Haematology, Children's Hospital Oxford, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - K A Rodriguez-Wallberg
- Department of Oncology Pathology, Karolinska Institutet, Solna, Sweden.,Section of Reproductive Medicine, Division of Gynecology and Reproduction, Karolinska University Hospital, Stockholm, Sweden
| | - A Rives
- Normandie Univ, UNIROUEN, EA 4308 "Gametogenesis and Gamete Quality", Rouen University Hospital, Biology of Reproduction-CECOS Laboratory, F 76000, Rouen, France
| | - H Valli-Pulaski
- Magee-Womens Research Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - S Steimer
- Magee-Womens Research Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - S Kliesch
- Centre of Reproductive Medicine and Andrology, Institute of Reproductive and Regenerative Biology, University of Münster, Münster, Germany
| | - A Braye
- Biology of the Testis, Research Laboratory for Reproduction, Genetics and Regenerative Medicine, Vrije Universiteit Brussel (VUB), 1090 Brussels, Belgium
| | - M M Andres
- Reproductive Medicine Unit, Hospital Universitario y Politécnico La Fe, Valencia, Spain
| | - J Medrano
- Reproductive Medicine Unit, Hospital Universitario y Politécnico La Fe, Valencia, Spain
| | - L Ramos
- Departement of Obstetrics and Gynacology, Division Reproductive Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
| | - S G Kristensen
- Laboratory of Reproductive Biology, The Juliane Marie Centre for Women, Children and Reproduction, University Hospital of Copenhagen, Denmark
| | - C Y Andersen
- Laboratory of Reproductive Biology, The Juliane Marie Centre for Women, Children and Reproduction, University Hospital of Copenhagen, Denmark
| | - R Bjarnason
- Children's Medical Center, Landspítali University Hospital, Reykjavik, Iceland and Faculty of Medicine, University of Iceland, Reykjavik, Iceland
| | - K E Orwig
- Magee-Womens Research Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - N Neuhaus
- Centre of Reproductive Medicine and Andrology, Institute of Reproductive and Regenerative Biology, University of Münster, Münster, Germany
| | - J B Stukenborg
- NORDFERTIL Research Lab Stockholm, Childhood Cancer Research Unit, Department of Women's and Children's Health, Karolinska Institutet and Karolinska University Hospital, Solna, Sweden
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Harpelunde Poulsen K, Nielsen JE, Grønkær Toft B, Joensen UN, Rasmussen LJ, Blomberg Jensen M, Mitchell RT, Juul A, Rajpert-De Meyts E, Jørgensen A. Influence of Nodal signalling on pluripotency factor expression, tumour cell proliferation and cisplatin-sensitivity in testicular germ cell tumours. BMC Cancer 2020; 20:349. [PMID: 32326899 PMCID: PMC7181506 DOI: 10.1186/s12885-020-06820-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Accepted: 04/02/2020] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Testicular germ cell tumours (TGCTs) are characterised by an overall high cisplatin-sensitivity which has been linked to their continued expression of pluripotency factors. Recently, the Nodal signalling pathway has been implicated in the regulation of pluripotency factor expression in fetal germ cells, and the pathway could therefore also be involved in regulating expression of pluripotency factors in malignant germ cells, and hence cisplatin-sensitivity in TGCTs. METHODS We used in vitro culture of the TGCT-derived cell line NTera2, ex vivo tissue culture of primary TGCT specimens and xenografting of NTera2 cells into nude mice in order to investigate the consequences of manipulating Nodal and Activin signalling on pluripotency factor expression, apoptosis, proliferation and cisplatin-sensitivity. RESULTS The Nodal signalling factors were markedly expressed concomitantly with the pluripotency factor OCT4 in GCNIS cells, seminomas and embryonal carcinomas. Despite this, inhibition of Nodal and Activin signalling either alone or simultaneously did not affect proliferation or apoptosis in malignant germ cells in vitro or ex vivo. Interestingly, inhibition of Nodal signalling in vitro reduced the expression of pluripotency factors and Nodal pathway genes, while stimulation of the pathway increased their expression. However, cisplatin-sensitivity was not affected following pharmacological inhibition of Nodal/Activin signalling or siRNA-mediated knockdown of the obligate co-receptor CRIPTO in NTera2 cells in vitro or in a xenograft model. CONCLUSION Our findings suggest that the Nodal signalling pathway may be involved in regulating pluripotency factor expression in malignant germ cells, but manipulation of the pathway does not appear to affect cisplatin-sensitivity or tumour cell proliferation.
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Affiliation(s)
- K Harpelunde Poulsen
- Department of Growth and Reproduction, Copenhagen University Hospital (Rigshospitalet), Blegdamsvej 9, DK-2100, Copenhagen, Denmark.,International Research and Research Training Centre in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), Blegdamsvej 9, Copenhagen, Denmark
| | - J E Nielsen
- Department of Growth and Reproduction, Copenhagen University Hospital (Rigshospitalet), Blegdamsvej 9, DK-2100, Copenhagen, Denmark.,International Research and Research Training Centre in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), Blegdamsvej 9, Copenhagen, Denmark
| | - B Grønkær Toft
- Pathology Department, Copenhagen University Hospital (Rigshospitalet), Blegdamsvej 9, 2100, Copenhagen, Denmark
| | - U N Joensen
- Department of Urology, Copenhagen University Hospital (Rigshospitalet), Blegdamsvej 9, 2100, Copenhagen, Denmark
| | - L J Rasmussen
- Department of Cellular and Molecular Medicine, Center for Healthy Aging, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen, Denmark
| | - M Blomberg Jensen
- Department of Growth and Reproduction, Copenhagen University Hospital (Rigshospitalet), Blegdamsvej 9, DK-2100, Copenhagen, Denmark
| | - R T Mitchell
- MRC Centre for Reproductive Health, The Queen's Medical Research Institute, University of Edinburgh, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK
| | - A Juul
- Department of Growth and Reproduction, Copenhagen University Hospital (Rigshospitalet), Blegdamsvej 9, DK-2100, Copenhagen, Denmark.,International Research and Research Training Centre in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), Blegdamsvej 9, Copenhagen, Denmark
| | - E Rajpert-De Meyts
- Department of Growth and Reproduction, Copenhagen University Hospital (Rigshospitalet), Blegdamsvej 9, DK-2100, Copenhagen, Denmark.,International Research and Research Training Centre in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), Blegdamsvej 9, Copenhagen, Denmark
| | - A Jørgensen
- Department of Growth and Reproduction, Copenhagen University Hospital (Rigshospitalet), Blegdamsvej 9, DK-2100, Copenhagen, Denmark. .,International Research and Research Training Centre in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), Blegdamsvej 9, Copenhagen, Denmark.
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Stukenborg JB, Alves-Lopes JP, Kurek M, Albalushi H, Reda A, Keros V, Töhönen V, Bjarnason R, Romerius P, Sundin M, Norén Nyström U, Langenskiöld C, Vogt H, Henningsohn L, Mitchell RT, Söder O, Petersen C, Jahnukainen K. Spermatogonial quantity in human prepubertal testicular tissue collected for fertility preservation prior to potentially sterilizing therapy. Hum Reprod 2018; 33:1677-1683. [PMID: 30052981 PMCID: PMC6112575 DOI: 10.1093/humrep/dey240] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Accepted: 06/15/2018] [Indexed: 11/24/2022] Open
Abstract
STUDY QUESTION Does chemotherapy exposure (with or without alkylating agents) or primary diagnosis affect spermatogonial quantity in human prepubertal testicular tissue? SUMMARY ANSWER Spermatogonial quantity is significantly reduced in testes of prepubertal boys treated with alkylating agent therapies or with hydroxyurea for sickle cell disease. WHAT IS KNOWN ALREADY Cryopreservation of spermatogonial stem cells, followed by transplantation into the testis after treatment, is a proposed clinical option for fertility restoration in children. The key clinical consideration behind this approach is a sufficient quantity of healthy cryopreserved spermatogonia. However, since most boys with malignancies start therapy with agents that are not potentially sterilizing, they will have already received some chemotherapy before testicular tissue cryopreservation is considered. STUDY DESIGN, SIZE, DURATION We examined histological sections of prepubertal testicular tissue to elucidate whether chemotherapy exposure or primary diagnosis affects spermatogonial quantity. Quantity of spermatogonia per transverse tubular cross-section (S/T) was assessed in relation to treatment characteristics and normative reference values in histological sections of paraffin embedded testicular tissue samples collected from 32 consecutive boy patients (aged 6.3 ± 3.8 [mean ± SD] years) between 2014 and 2017, as part of the NORDFERTIL study, and in 14 control samples (from boys aged 5.6 ± 5.0 [mean ± SD] years) from an internal biobank. PARTICIPANTS/MATERIALS, SETTING, METHODS Prepubertal boys in Sweden, Finland and Iceland who were facing treatments associated with a very high risk of infertility, were offered the experimental procedure of testicular cryopreservation. Exclusion criteria were testicular volumes >10 ml and high bleeding or infection risk. There were 18 patients with a diagnosis of malignancy and 14 patients a non-malignant diagnosis. While 20 patients had the testicular biopsy performed 1-45 days after chemotherapy, 12 patients had not received any chemotherapy. In addition, 14 testicular tissue samples of patients with no reported testicular pathology, obtained from the internal biobank of the Department of Pathology at Karolinska University Hospital, were included as control samples in addition to reference values obtained from a recently published meta-analysis. The quantity of spermatogonia was assessed by both morphological and immunohistochemical analysis. MAIN RESULTS AND THE ROLE OF CHANCE The main finding was a significant reduction in spermatogonial cell counts in boys treated with alkylating agents or with hydroxyurea for sickle cell disease. The mean S/T values in boys exposed to alkylating agents (0.2 ± 0.3, n = 6) or in boys with sickle cell disease and exposed to hydroxyurea (0.3 ± 0.6, n = 6) were significantly lower (P = 0.003 and P = 0.008, respectively) than in a group exposed to non-alkylating agents or in biobank control samples (1.7 ± 1.0, n = 8 and 4.1 ± 4.6, n = 14, respectively). The mean S/T values of the testicular tissue samples included in the biobank control group and the patient group exposed to non-alkylating agents were within recently published normative reference values. LIMITATIONS, REASONS FOR CAUTION Normal testicular tissue samples included in this study were obtained from the internal biobank of Karolinska University Hospital. Samples were considered normal and included in the study if no testicular pathology was reported in the analysed samples. However, detailed information regarding previous medical treatments and testicular volumes of patients included in this biobank were not available. WIDER IMPLICATIONS OF THE FINDINGS This study summarizes, for the first time, spermatogonial quantity in a prepubertal patient cohort just before and after potentially sterilizing treatments. Boys facing cancer and cytotoxic therapies are regarded as the major group who will benefit from novel fertility preservation techniques. There are no previous reports correlating spermatogonial quantity to cumulative exposure to alkylating agents and anthracyclines (non-alkylating agents) and no information about the timing of cytotoxic exposures among this particular patient cohort. For prepubertal boys in whom fertility preservation is indicated, testicular tissue should be obtained before initiation of chemotherapy with alkylating agents, whilst for those with sickle cell disease and treated with hydroxyurea, this approach to fertility preservation may not be feasible. STUDY FUNDING/COMPETING INTEREST(S) This study was supported by grants from The Swedish Childhood Cancer Foundation (PR2016-0124; TJ2016-0093; PR2015-0073, TJ2015-0046) (J.-B.S. and K.J.), the Jane and Dan Olssons Foundation (2016-33) (J.-B.S.), the Finnish Cancer Society (K.J.), the Foundation for Paediatric Research (J.-B.S.), Kronprinsessan Lovisas Förening För Barnasjukvård/ Stiftelsen Axel Tielmans Minnesfond, Samariten Foundation (J.-B.S.), the Väre Foundation for Paediatric Cancer Research (K.J.) and the Swedish Research Council (2012-6352) (O.S.). R.T.M. was supported by a Wellcome Trust Fellowship (09822). J.P.A.-L. and M.K. were supported by the ITN Marie Curie program 'Growsperm' (EU-FP7-PEOPLE-2013-ITN 603568). The authors declare no conflicts of interest. TRIAL REGISTRATION NUMBER N/A.
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Affiliation(s)
- J-B Stukenborg
- NORDFERTIL Research Lab Stockholm, Department of Women's and Children's Health, Karolinska Institutet and University Hospital, Stockholm, Sweden
- Pediatric Endocrinology Unit, Department of Women's and Children's Health, Karolinska Institutet and University Hospital, Stockholm, Sweden
| | - J P Alves-Lopes
- NORDFERTIL Research Lab Stockholm, Department of Women's and Children's Health, Karolinska Institutet and University Hospital, Stockholm, Sweden
- Pediatric Endocrinology Unit, Department of Women's and Children's Health, Karolinska Institutet and University Hospital, Stockholm, Sweden
| | - M Kurek
- NORDFERTIL Research Lab Stockholm, Department of Women's and Children's Health, Karolinska Institutet and University Hospital, Stockholm, Sweden
- Pediatric Endocrinology Unit, Department of Women's and Children's Health, Karolinska Institutet and University Hospital, Stockholm, Sweden
| | - H Albalushi
- NORDFERTIL Research Lab Stockholm, Department of Women's and Children's Health, Karolinska Institutet and University Hospital, Stockholm, Sweden
- Pediatric Endocrinology Unit, Department of Women's and Children's Health, Karolinska Institutet and University Hospital, Stockholm, Sweden
- Sultan Qaboos University, College of Medicine and Health Sciences, Muscat, Oman
| | - A Reda
- Pediatric Endocrinology Unit, Department of Women's and Children's Health, Karolinska Institutet and University Hospital, Stockholm, Sweden
- Department of Development and Regeneration, Organ System Cluster, Group of Biomedical Sciences, KU Leuven, Herestraat 49, Leuven, Belgium
| | - V Keros
- Reproductive Medicine, Department of Obstetrics and Gynaecology, Karolinska University Hospital, Stockholm, Sweden
- Department of Medicine, Karolinska Institutet, Stockholm, Sweden
| | - V Töhönen
- Reproductive Medicine, Department of Obstetrics and Gynaecology, Karolinska University Hospital, Stockholm, Sweden
- Department of Medicine, Karolinska Institutet, Stockholm, Sweden
| | - R Bjarnason
- Clinic and University, Children's Medical Center, Landspítali University Hospital, Reykjavik, Iceland
- Faculty of Medicine, University of Iceland, Reykjavik, Iceland
| | - P Romerius
- Department of Paediatric Oncology and Haematology, Clinical Sciences, Lund University, Lund, Sweden
| | - M Sundin
- Division of Paediatrics, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden
- Pediatric Blood Disorders, Immunodeficiency and Stem Cell Transplantation, Astrid Lindgren Children's Hospital, Karolinska University Hospital, Stockholm, Sweden
| | - U Norén Nyström
- Clinical Sciences, Paediatrics, Umeå University, Umeå, Sweden
| | - C Langenskiöld
- Department of Paediatric Oncology, The Queen Silvia Children's Hospital, Gothenburg, Sweden
| | - H Vogt
- Department of Paediatrics, Faculty of Health Sciences, Linköping University, Linköping, Sweden
- Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linköping University, Linköping, Sweden
| | - L Henningsohn
- Division of Urology, Institution for Clinical Science Intervention and Technology, Karolinska Institutet, Huddinge, Stockholm, Sweden
| | - R T Mitchell
- MRC Centre for Reproductive Health, The Queen's Medical Research Institute, The University of Edinburgh, Edinburgh, UK
- The Edinburgh Royal Hospital for Sick Children, Edinburgh, UK
| | - O Söder
- Pediatric Endocrinology Unit, Department of Women's and Children's Health, Karolinska Institutet and University Hospital, Stockholm, Sweden
| | - C Petersen
- NORDFERTIL Research Lab Stockholm, Department of Women's and Children's Health, Karolinska Institutet and University Hospital, Stockholm, Sweden
- Pediatric Endocrinology Unit, Department of Women's and Children's Health, Karolinska Institutet and University Hospital, Stockholm, Sweden
- Department of Women's and Children's Health, Paediatric Oncology Unit, Karolinska Institutet, Stockholm, Sweden
- University Hospital, Stockholm, Sweden
| | - K Jahnukainen
- NORDFERTIL Research Lab Stockholm, Department of Women's and Children's Health, Karolinska Institutet and University Hospital, Stockholm, Sweden
- Pediatric Endocrinology Unit, Department of Women's and Children's Health, Karolinska Institutet and University Hospital, Stockholm, Sweden
- Division of Haematology-Oncology and Stem Cell Transplantation, Children´s Hospital, University of Helsinki, Helsinki University Central Hospital, Helsinki, Finland
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Mitchell RT, Sun A, Mayo A, Forgan M, Comrie A, Gillett PM. Coeliac screening in a Scottish cohort of children with type 1 diabetes mellitus: is DQ typing the way forward? Arch Dis Child 2016; 101:230-3. [PMID: 26718815 PMCID: PMC4789707 DOI: 10.1136/archdischild-2015-309754] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2015] [Accepted: 11/23/2015] [Indexed: 12/12/2022]
Abstract
BACKGROUND Children with type 1 diabetes mellitus (T1DM) are at increased risk of coeliac disease (CD). Recent guidelines indicate coeliac screening should include HLA typing for CD predisposing (DQ2/DQ8) alleles and those negative for these alleles require no further coeliac screening. METHODS Children (n=176) with T1DM attending clinics across two Scottish regions were screened for HLA DQ2/DQ8 as part of routine screening. Data collected included the frequency of DQ2/DQ8 genotypes and the additional cost of HLA screening. RESULTS Overall, DQ2/DQ8 alleles were identified in 94% of patients. The additional cost of HLA typing was £3699.52 (£21.02 per patient). All patients with known CD (11/176) were positive for DQ2/DQ8 and all were diagnosed with CD within 5 years of T1DM diagnosis. CONCLUSIONS The vast majority of children with T1DM have CD-predisposing HLA genotypes limiting the number of patients that can be excluded from further screening. We conclude that HLA genotyping is not currently indicated for CD screening in this population.
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Affiliation(s)
- R T Mitchell
- MRC Centre for Reproductive Health, The Queen's Medical Research Institute, The University of Edinburgh,Edinburgh, UK,Departments of Paediatric Diabetes (RTM) and Paediatric Gastroenterology (PMG), Royal Hospital for Sick Children, Edinburgh, UK
| | - A Sun
- Departments of Paediatric Diabetes, Royal Aberdeen Children's Hospital, Aberdeen, UK
| | - A Mayo
- Departments of Paediatric Diabetes, Royal Aberdeen Children's Hospital, Aberdeen, UK
| | - M Forgan
- BTS Tissue Typing, Ninewells Hospital, Dundee, UK
| | - A Comrie
- BTS Tissue Typing, Ninewells Hospital, Dundee, UK
| | - P M Gillett
- Departments of Paediatric Diabetes (RTM) and Paediatric Gastroenterology (PMG), Royal Hospital for Sick Children, Edinburgh, UK
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Jørgensen A, Nielsen JE, Perlman S, Lundvall L, Mitchell RT, Juul A, Rajpert-De Meyts E. Ex vivo culture of human fetal gonads: manipulation of meiosis signalling by retinoic acid treatment disrupts testis development. Hum Reprod 2015; 30:2351-63. [PMID: 26251460 DOI: 10.1093/humrep/dev194] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Accepted: 07/13/2015] [Indexed: 01/01/2023] Open
Abstract
STUDY QUESTION What are the effects of experimentally manipulating meiosis signalling by addition of retinoic acid (RA) in cultured human fetal gonads? SUMMARY ANSWER RA-treatment accelerated meiotic entry in cultured fetal ovary samples, while addition of RA resulted in a dysgenetic gonadal phenotype in fetal testis cultures. WHAT IS KNOWN ALREADY One of the first manifestations of sex differentiation is the initiation of meiosis in fetal ovaries. In contrast, meiotic entry is actively prevented in the fetal testis at this developmental time-point. It has previously been shown that RA-treatment mediates initiation of meiosis in human fetal ovary ex vivo. STUDY DESIGN, SIZE, DURATION This was a controlled ex vivo study of human fetal gonads treated with RA in 'hanging-drop' tissue cultures. The applied experimental set-up preserves germ cell-somatic niche interactions and the investigated outcomes included tissue integrity and morphology, cell proliferation and survival and the expression of markers of meiosis and sex differentiation. PARTICIPANTS/MATERIALS, SETTING, METHODS Tissue from 24 first trimester human fetuses was included in this study, all from elective terminations at gestational week (GW) 7-12. Gonads were cultured for 2 weeks with and without addition of 1 µM RA. Samples were subsequently formalin-fixed and investigated by immunohistochemistry and cell counting. Proteins investigated and quantified included; octamer-binding transcription factor 4 (OCT4), transcription factor AP-2 gamma (AP2γ) (embryonic germ cell markers), SRY (sex determining region Y)-box 9 (SOX9), anti-Müllerian hormone (AMH) (immature Sertoli cell markers), COUP transcription factor 2 (COUP-TFII) (marker of interstitial cells), forkhead box L2 (FOXL2) (granulosa cell marker), H2A histone family, member X (γH2AX) (meiosis marker), doublesex and mab-3 related transcription factor 1 (DMRT1) (meiosis regulator), cleaved poly ADP ribose polymerase (PARP), cleaved Caspase 3 (apoptosis markers) and Ki-67 antigen (Ki-67) (proliferation marker). Also, proliferation was determined using a 5'-bromo-2'-deoxyuridine (BrdU) incorporation assay. MAIN RESULTS AND THE ROLE OF CHANCE A novel ex vivo 'hanging-drop' culture model for human fetal gonads was successfully established. Continued proliferation of cells without signs of increased apoptosis was observed after 2 weeks of culture. In cultured fetal ovaries treated with RA, an increased number of meiotic germ cells (P < 0.05) and DMRT1-positive oogonia initiating meiosis (P < 0.05) was observed, which is in agreement with a previous study. In fetal testes, RA-treatment resulted in a decreased number of gonocytes (P < 0.05), a reduced percentage of proliferating gonocytes (P < 0.05), altered expression pattern of the somatic cell markers AMH and COUP-TFII, as well as disrupted seminiferous cord structure and testis morphology. LIMITATIONS, REASONS FOR CAUTION The number of samples included in this study was relatively small due to the limited availability of human fetal tissue. WIDER IMPLICATIONS OF THE FINDINGS The hanging-drop culture, similarly to other organ culture approaches, allows studies of germ cell-somatic niche interactions and determination of effects after manipulating specific signalling pathways. Our novel finding of disrupted fetal testis development after treatment with RA indicates that abnormal meiosis regulation can potentially cause gonadal dysgenesis. Further studies will elucidate the exact mechanisms and timing of observed effects. STUDY FUNDING/COMPETING INTERESTS This work was supported in part by an ESPE Research Fellowship, sponsored by Novo Nordisk A/S to A.Jø. Additional funding for this project was obtained from The Research Council of the Capital Region of Denmark (E.R.-D.M.), The Research Fund at Rigshospitalet (A.Ju. and J.E.N.), Familien Erichssens Fund (A.Jø.), Dagmar Marshalls Fund (A.Jø.) and Aase & Ejnar Danielsens Fund (A.Jø.). The authors have no conflicts of interest.
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Affiliation(s)
- A Jørgensen
- University Department of Growth and Reproduction and EDMaRC, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - J E Nielsen
- University Department of Growth and Reproduction and EDMaRC, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - S Perlman
- Department of Gynaecology, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, Copenhagen DK-2100, Denmark
| | - L Lundvall
- Department of Gynaecology, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, Copenhagen DK-2100, Denmark
| | - R T Mitchell
- MRC Centre for Reproductive Health, The University of Edinburgh, The Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh EH16 4TJ, UK Edinburgh Royal Hospital for Sick Children, 9 Sciennes Road, Edinburgh EH9 1LF, UK
| | - A Juul
- University Department of Growth and Reproduction and EDMaRC, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - E Rajpert-De Meyts
- University Department of Growth and Reproduction and EDMaRC, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
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Mitchell RT, Childs AJ, Anderson RA, van den Driesche S, Saunders PTK, McKinnell C, Wallace WHB, Kelnar CJH, Sharpe RM. Do phthalates affect steroidogenesis by the human fetal testis? Exposure of human fetal testis xenografts to di-n-butyl phthalate. J Clin Endocrinol Metab 2012; 97:E341-8. [PMID: 22238399 DOI: 10.1210/jc.2011-2411] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
CONTEXT Phthalates are ubiquitous environmental chemicals. Fetal exposure to certain phthalates [e.g. di-n-butyl phthalate (DBP)] causes masculinization disorders in rats, raising concern for similar effects in humans. We investigated whether DBP exposure impairs steroidogenesis by the human fetal testis. OBJECTIVE The aim of the study was to determine effects of DBP exposure on testosterone production by normally growing human fetal testis xenografts. DESIGN Human fetal testes (14-20 wk gestation; n=12) were xenografted into castrate male nude mice that were treated for 4-21 d with vehicle, or 500 mg/kg·d DBP, or monobutyl phthalate (active metabolite of DBP); all mice were treated with human chorionic gonadotropin to mimic normal human pregnancy. Rat fetal testis xenografts were exposed for 4 d to DBP as a positive control. MAIN OUTCOME MEASURES Testosterone production was assessed by measuring host serum testosterone and seminal vesicle (SV) weights at termination, plus testis gene expression (rats). RESULTS Human fetal testis xenografts showed similar survival (∼80%) and total graft weight (8.6 vs. 10.1 mg) in vehicle and DBP-exposed hosts, respectively. Serum testosterone (0.56 vs. 0.64 ng/ml; P>0.05) and SV weight (67.2 vs. 81.9 mg; P>0.05) also did not differ. Exposure to monobutyl phthalate gave similar results. In contrast, exposure of rat fetal xenografts to DBP significantly reduced SV weight and testis Cyp11a1/StAR mRNA expression and lowered testosterone levels, confirming that DBP exposure can inhibit steroidogenesis in xenografts, further validating the negative findings on testosterone production in the human. CONCLUSIONS Exposure of human fetal testes to DBP is unlikely to impair testosterone production as it does in rats. This has important safety and regulatory implications.
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Affiliation(s)
- R T Mitchell
- Medical Research Council/University of Edinburgh Centre for Reproductive Health, The Queen's Medical Research Institute, Edinburgh Royal Hospital for Sick Children, 47 Little France Crescent, Edinburgh EH16 4TJ, Scotland, United Kingdom.
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Mitchell RT, Saunders PTK, Sharpe RM, Kelnar CJH, Wallace WHB. Male fertility and strategies for fertility preservation following childhood cancer treatment. Endocr Dev 2009; 15:101-134. [PMID: 19293606 DOI: 10.1159/000207612] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Infertility in the male is a potential complication of childhood cancer treatment for long-term survivors. The risk is dependent primarily on the treatment used, but also on the underlying disease. Chemotherapy (especially alkylating agents) and radiotherapy, even in low doses, may damage the seminiferous epithelium and impair spermatogenesis in both children and adults. Leydig cell function and testosterone production are generally preserved after chemotherapy and low dose radiotherapy, whilst larger doses of radiotherapy may result in hypogonadism. Patients treated with potentially gonadotoxic treatments require regular multidisciplinary follow-up including assessment of puberty and gonadal function. Currently the only option available for fertility preservation in young males treated for cancer is semen cryopreservation. For pre-pubertal patients, techniques for fertility preservation remain theoretical and as yet unproven. These include hormonal manipulation of the gonadal environment before treatment, germ cell transplantation and testis xenografting, which have all shown promise in a variety of animal studies. Refinement of these techniques requires investigations in relevant animal models. In the present chapter we include data which suggest that the common marmoset (Callithrix jacchus) monkey, a New World primate, exhibits important parallels with human testicular development and may help us to understand why the pre-pubertal testis is vulnerable to effects of cytotoxic therapy on future fertility.
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14
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Mitchell RT, Cowan G, Morris KD, Anderson RA, Fraser HM, Mckenzie KJ, Wallace WHB, Kelnar CJH, Saunders PTK, Sharpe RM. Germ cell differentiation in the marmoset (Callithrix jacchus) during fetal and neonatal life closely parallels that in the human. Hum Reprod 2008; 23:2755-65. [PMID: 18694875 PMCID: PMC2583943 DOI: 10.1093/humrep/den295] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Testicular germ cell tumours (TGCT) are thought to originate from fetal germ cells that fail to differentiate normally, but no animal model for these events has been described. We evaluated the marmoset (Callithrix jacchus) as a model by comparing perinatal germ cell differentiation with that in humans. METHODS Immunohistochemical profiling was used to investigate germ cell differentiation (OCT4, NANOG, AP-2gamma, MAGE-A4, VASA, NANOS-1) and proliferation (Ki67) in fetal and neonatal marmoset testes in comparison with the human and, to a lesser extent, the rat. RESULTS In marmosets and humans, differentiation of gonocytes into spermatogonia is associated with the gradual loss of pluripotency markers such as OCT4 and NANOG, and the expression of germ cell-specific proteins such as VASA. This differentiation occurs asynchronously within individual cords during fetal and early postnatal life. This contrasts with rapid and synchronous germ cell differentiation within and between cords in the rat. Similarly, germ cell proliferation in the marmoset and human occurs throughout perinatal life, in contrast to rats in which proliferation ceases during this period. CONCLUSIONS The marmoset provides a good model for normal human germ cell differentiation and proliferation. The perinatal marmoset may be a useful model in which to establish factors that lead to failure of normal germ cell differentiation and the origins of TGCT.
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Affiliation(s)
- R T Mitchell
- MRC Human Reproductive Sciences Unit, Centre for Reproductive Biology, The Queen's Medical Research Institute, Edinburgh, Scotland, UK.
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15
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Little CL, Surman-Lee S, Greenwood M, Bolton FJ, Elson R, Mitchell RT, Nichols GN, Sagoo SK, Threlfall EJ, Ward LR, Gillespie IA, O'Brien S. Public health investigations of Salmonella Enteritidis in catering raw shell eggs, 2002-2004. Lett Appl Microbiol 2007; 44:595-601. [PMID: 17576219 DOI: 10.1111/j.1472-765x.2007.02131.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
AIMS In response to a dramatic change in the epidemiology of Salmonella Enteritidis in England and Wales thought to be associated with raw shell eggs, the Health Protection Agency initiated public health investigations to establish the incidence of Salmonella contamination and origin of eggs used by catering premises implicated in outbreaks of Salm. Enteritidis. METHODS AND RESULTS Between October 2002 and November 2004, 16 971 eggs were sampled and Salmonella were recovered from 3.4%. Salmonella was isolated from 5.5% and 6.3% of Spanish and eggs of unknown origin, respectively, used in catering premises linked to outbreaks, a level significantly higher than that (1.1%) found in nonLion Quality UK eggs sampled. The small sample of UK Lion Quality eggs tested (reflecting their lack of use in premises visited) did not contain Salmonella. Several phage types of Salm. Enteritidis other than phage type 4 (PT 4) were identified with nonUK eggs. CONCLUSIONS Eggs from Spain were implicated as a major source of infection. Eggs were contaminated more frequently with Salmonella when shells were dirty and/or cracked, and stored at above 8 degrees C. SIGNIFICANCE AND IMPACT OF THE STUDY The use of Spanish eggs by the catering sector has been identified as a consistent significant factor in many of the outbreaks caused by Salm. Enteritidis nonPT4 in England and Wales during 2002-2004. Advice to caterers and hospitals that raw shell eggs should not be used in food that will either not be cooked or only lightly cooked should be reinforced.
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Affiliation(s)
- C L Little
- Department of Gastrointestinal Infections, Health Protection Agency Centre for Infections, London, UK.
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16
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Elson R, Little CL, Mitchell RT. Salmonella and raw shell eggs: results of a cross-sectional study of contamination rates and egg safety practices in the United Kingdom catering sector in 2003. J Food Prot 2005; 68:256-64. [PMID: 15726966 DOI: 10.4315/0362-028x-68.2.256] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
This study was prompted by epidemiological investigations of the unusual number of Salmonella Enteritidis outbreaks associated with the use of eggs in catering premises in England and Wales during 2002. The aims of the study, performed between April and May 2003, were to establish the rate of Salmonella contamination in raw shell eggs from catering premises, investigate any correlation between the origin and type of eggs and the presence of particular serotypes or phage types (PTs) of Salmonella, and examine the use of raw shell eggs in catering premises in the United Kingdom. A total of 34,116 eggs (5,686 pooled samples of six eggs) were collected from 2,104 catering premises, most of which were eggs produced in the United Kingdom (88%). Salmonella was isolated from 17 pools (0.3%) of eggs. Of these, 15 were Salmonella Enteritidis, which were further characterized to PTs as follows: PT6 (0.1%), PT4 (0.07%), PT12 (0.04%), PT1 (0.04%), and PT14b (0.02%). Salmonella Livingstone and Salmonella Typhimurium definitive type 7 resistant to ampicillin, streptomycin, sulfonamides, and tetracycline were also isolated. The Salmonella contamination rate of eggs produced in the United Kingdom appears to have decreased significantly since 1995 and 1996. This trend is reflected in the decrease of Salmonella Enteritidis and, in particular, Salmonella Enteritidis PT4. The impact of the United Kingdom Food Standards Agency's advice on the use of eggs, issued in January 2003, is discussed.
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Affiliation(s)
- R Elson
- Environmental Surveillance Unit, Health Protection Agency Communicable Disease Surveillance Centre, 61 Colindale Avenue, London NW9 5EQ, UK.
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17
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Little CL, Mitchell RT. Microbiological quality of pre-cut fruit, sprouted seeds, and unpasteurised fruit and vegetable juices from retail and production premises in the UK, and the application of HAACP. Commun Dis Public Health 2004; 7:184-90. [PMID: 15481210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Abstract
A study of ready-to-eat pre-cut fruit, sprouted seeds, and unpasteurised fruit and vegetable juices from retail and production premises was undertaken in the UK to determine the microbiological quality of these products, and to verify the application of hazard analysis and critical control points (HACCP) procedures by food operators. Almost all (99%; 2,075/2,096) samples were of satisfactory/acceptable microbiological quality. Two (0.1%) samples (melon, beansprouts) were of unacceptable quality due to the presence of Listeria monocytogenes at 102 cfu/g or more while a further 19 (0.9%) were unsatisfactory due to Escherichia coli levels in the range of 102 to 106 cfu/g. Neither Salmonella spp. nor E. coli O157 were detected in samples examined. A hazard analysis system was in place in most (85%) premises visited, and in 80% it was documented. Most managers (83%) had received some form of food hygiene training. Minimally processed produce is exposed to a range of conditions during production and distribution, and this may increase the potential for microbial contamination, highlighting the need of applying good hygiene practices from farm to fork to prevent contamination and/or bacterial growth. Such products should be stored and displayed at or below 8 degrees C.
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Affiliation(s)
- C L Little
- Health Protection Agency, Environmental Surveillance Unit, Environmental and Enterics Diseases Department, Communicable Disease Surveillance Centre, London.
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McLauchlin J, Mitchell RT, Smerdon WJ, Jewell K. Listeria monocytogenes and listeriosis: a review of hazard characterisation for use in microbiological risk assessment of foods. Int J Food Microbiol 2004; 92:15-33. [PMID: 15033265 DOI: 10.1016/s0168-1605(03)00326-x] [Citation(s) in RCA: 236] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2003] [Revised: 04/30/2003] [Accepted: 05/30/2003] [Indexed: 11/24/2022]
Abstract
Considerable effort has been put into the application of quantitative microbiological risk assessment for Listeria monocytogenes, and data are available for England and Wales (probably more so than most other countries) on the adverse health effects, together with incidence data on different age and risk groups for human L. monocytogenes infections. This paper reviews aspects of Listeria and human listeriosis, especially from a public health perspective and provide hazard characterisation data, i.e. the qualitative and/or quantitative evaluation of the adverse health effect associated with the hazard, which is the relationship between exposure levels (dose) and frequency of illness. The majority of cases of human listeriosis are food-borne; however, the disease process is complex with multiple routes of infection. The dose-response relationship is poorly understood, and data from human volunteer studies are not available and would be unethical to produce. Data are available from a range of different animal and in vitro models, although these poorly mimic the natural disease process in route of infection, end point, host and history of prior exposure to the bacterium. Epidemiological data provide some information on infective doses and dose responses, but because of the characteristics of the disease (the hugely variable and potentially very long incubation periods, the low attack rates and the rarity of identification of specific food vehicles), this also provides limited data for calculation of dose responses. There is some, albeit limited, evidence for strain variation, but this is an area of considerable uncertainty despite great advances in the genetic basis of the virulence of this bacterium, and almost all strains seem capable of causing serious disease. A variety of mathematical approaches have been used to model dose responses. The review is written to provide a clinical and epidemiological background to the mathematically oriented, as well as to outline the mathematical approaches to those interested in food-borne infection.
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Affiliation(s)
- J McLauchlin
- Health Protection Agency, Food Safety Microbiology Laboratory, Division of Gastrointestinal Infections, Central Public Health Laboratory, 61 Colindale Avenue, London NW9 5HT, UK.
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Elson R, Burgess F, Little CL, Mitchell RT. Microbiological examination of ready-to-eat cold sliced meats and pate from catering and retail premises in the UK. J Appl Microbiol 2004; 96:499-509. [PMID: 14962130 DOI: 10.1111/j.1365-2672.2004.02203.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
AIMS To establish the microbiological quality of cold ready-to-eat sliced meats and pâté from catering and retail premises, and investigate links hypothesized between foodborne Campylobacter infection and the consumption of cold sliced meats. METHODS AND RESULTS A total of 4078 cold meat and pâté samples were collected and examined according to a standardized protocol. Comparison with published microbiological guidelines revealed that most ready-to-eat meat and pâté samples (75%) were of satisfactory/acceptable microbiological quality and 25% were of unsatisfactory/unacceptable quality. Two cold meat samples (<1%) were of unacceptable microbiological quality because of the presence of Campylobacter jejuni in 25 g and Listeria monocytogenes at 3.4 x 104 CFU g-1. CONCLUSIONS Acceptable microbiological quality was associated with premises where the management was trained in food hygiene and those that had hazard analysis in place. Poor microbiological quality was associated with storage above 8 degrees C, presliced meats, infrequent cleaning of slicing equipment and poor control of practices that may lead to cross contamination. SIGNIFICANCE AND IMPACT OF THE STUDY This study provides important information about the microbiological quality of cold ready-to-eat meats and pâté. It also assists caterers, retailers, enforcement officers and policy makers to understand how different food safety practices affect microbiological quality.
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Affiliation(s)
- R Elson
- Environmental Surveillance Unit, Health Protection Agency Communicable Disease Surveillance Centre, London, UK
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20
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Little CL, Lock D, Barnes J, Mitchell RT. Microbiological quality of food in relation to hazard analysis systems and food hygiene training in UK catering and retail premises. Commun Dis Public Health 2003; 6:250-8. [PMID: 14708277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Abstract
A meta-analysis of eight UK food studies was carried out to determine the microbiological quality of food and its relationship with the presence in food businesses of hazard analysis systems and food hygiene training. Of the 19,022 premises visited to collect food samples in these studies between 1997 and 2002, two thirds (66%) were catering premises and one third (34%) were retail premises. Comparison with PHLS Microbiological Guidelines revealed that significantly more ready-to-eat food samples from catering premises (20%; 2,511/12,703) were of unsatisfactory or unacceptable microbiological quality compared to samples from retail premises (12%; 1,039/8,462) (p < 0.00001). Three quarters (76%) of retail premises had hazard analysis systems in place compared with 59% of catering premises (p < 0.00001). In 87% of retail premises the manager had received some form of food hygiene training compared with 80% of catering premises (p < 0.00001). From premises where the manager had received no food hygiene training a greater proportion of samples were of unsatisfactory and unacceptable microbiological quality (20% retail, 27% catering) compared with premises where the manager had received food hygiene training (11% retail, 19% catering) (p < 0.00001). Where the manager of the premises had received food hygiene training, documented hazard analysis systems were more likely to be in place (p < 0.00001). Higher proportions of samples of unsatisfactory and unacceptable microbiological quality (17% retail, 22% catering) were from premises where there was no hazard analysis system in place compared to premises that had a documented hazard analysis system in place (10% retail, 18% catering) (p < 0.00001). Our meta-analysis suggests that the lower microbiological quality of ready-to-eat foods from catering premises compared with those collected from retail premises may reflect differences in management food hygiene training and the presence of a hazard analysis system. The importance of adequate training for food handlers and their managers as a pre-requisite for effective hazard analysis and critical control point (HACCP) based controls is therefore emphasised.
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Affiliation(s)
- C L Little
- Environmental Surveillance Unit, Health Protection Agency, Communicable Disease Surveillance Centre, 61 Colindale Avenue, London NW9 5EQ.
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21
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Abstract
During September and October 2001, a microbiological study of open, ready-to-eat, prepared salad vegetables from catering or retail premises was undertaken to determine their microbiological quality. The study focused on those salad vegetables that were unwrapped and handled either by staff or customers in the premises where the sample was taken. Examination of salad vegetables from food service areas and customer self-service bars revealed that most (97%; 2,862 of 2,950) were of satisfactory or acceptable microbiological quality, 3% (87) were of unsatisfactory microbiological quality because of Escherichia coli levels in the range of 10(2) to 10(5) colony-forming units per gram. One (<1%) sample was of unacceptable microbiological quality because of the presence of Listeria monocytogenes at 840 colony-forming units per gram. The pathogens E. coli O157, Campylobacter spp., and salmonellas were not detected in any of the samples examined. The display area for most food service and preparation areas (95%) and self-service salad bars (98%) that were visited was judged to be visibly clean by the sampling officer. Most self-service bars (87%) were regularly supervised or inspected by staff during opening hours, and designated serving utensils were used in most salad bars (92%) but in only a minority of food service areas (35%). A hazard analysis system was in place in most (80%) premises, and in 61%, it was documented. Most (90%) managers had received food hygiene training. A direct relationship was shown between increased confidence in the food business management and the presence of food safety procedures and the training of management in food hygiene.
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Affiliation(s)
- S K Sagoo
- Environmental Surveillance Unit, Health Protection Agency, Communicable Disease Surveillance Centre, 61 Colindale Avenue, London NW9 5EQ, UK
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22
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Horby PW, O'Brien SJ, Adak GK, Graham C, Hawker JI, Hunter P, Lane C, Lawson AJ, Mitchell RT, Reacher MH, Threlfall EJ, Ward LR. A national outbreak of multi-resistant Salmonella enterica serovar Typhimurium definitive phage type (DT) 104 associated with consumption of lettuce. Epidemiol Infect 2003; 130:169-78. [PMID: 12729184 PMCID: PMC2869951 DOI: 10.1017/s0950268802008063] [Citation(s) in RCA: 103] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Between 1 August and 15 September 2000, 361 cases of Salmonella enterica serotype Typhimurium definitive phage type (DT) 104, resistant to ampicillin, chloramphenicol, streptomycin, sulphonamides, spectinomycin and tetracycline (R-type ACSSuSpT), were identified in England and Wales residents. Molecular typing of 258 isolates of S. Typhimurium DT104 R-type ACSSuSpT showed that, although isolates were indistinguishable by pulsed-field gel electrophoresis, 67% (174/258) were characterized by a particular plasmid profile. A statistically significant association between illness and consumption of lettuce away from home was demonstrated (OR = 7.28; 95% CI=2.25-23.57; P=0.0006) in an unmatched case-control study. Environmental investigations revealed that a number of food outlets implicated in the outbreak had common suppliers of salad vegetables. No implicated foods were available for microbiological testing. An environmental audit of three farms that might have supplied salad vegetables to the implicated outlets did not reveal any unsafe agricultural practices. The complexity of the food supply chain and the lack of identifying markers on salad stuffs made tracking salad vegetables back to their origin extremely difficult in most instances. This has implications for public health since food hazard warnings and product withdrawal are contingent on accurate identification of the suspect product.
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Affiliation(s)
- P W Horby
- Gastrointestinal Diseases Division, PHLS Communicable Disease Surveillance Centre (CDSC), 61 Colindale Avenue, London, NW9 5EQ, UK
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Sagoo SK, Little CL, Griffith CJ, Mitchell RT. Study of cleaning standards and practices in food premises in the United Kingdom. Commun Dis Public Health 2003; 6:6-17. [PMID: 12736965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
A study was undertaken to determine the microbiological status of surfaces used in the preparation of ready-to-eat foods, and to assess cleaning standards and practices in food premises in the UK. A total of 6,533 environmental samples were examined from 1,502 catering (such as restaurants, cafés, and sandwich bars) or retail premises (such as butchers, delicatessens, and bakers): 2,033 samples from chopping/cutting boards, 2,009 from worktop surfaces, 1,359 from food containers, and 1,132 from cleaning cloths. Cleaning cloths were more heavily contaminated with bacteria (Aerobic Colony Count (ACC), Enterobacteriaceae, E. coli, and Staph. aureus) compared to surfaces sampled. Campylobacter spp. were detected in two (0.2%) and Salmonella spp. from one (0.1%) of the cleaning cloths. Surfaces that were visually dirty, wet, last cleaned over 24 hours ago, and boards that were scored or damaged were found to have higher levels of bacteria. A hazard analysis system was in place in most (70%) food premises visited, and in 52% it was documented. Most managers (89%) had received some form of food hygiene training. Documented cleaning schedules and cleaning records were only present in approximately half (55% and 44%, respectively) of the premises. Most did not have separate implements for cleaning raw and ready-to-eat food areas (67%), or stored cleaning equipment for high risk (ready-to-eat food) areas away from those used in low risk (raw, non ready-to-eat food) areas (70%). Deficiencies in the correct use of cleaning products, such as the minimum contact time for disinfectants, were identified. Surface samples (chopping/cutting boards, worktops, and food containers) and cleaning cloths with ACC levels in excess of 10(3) cfu/cm2, swab or ml were associated with premises that did not have management food hygiene training, hazard analysis, cleaning schedules or cleaning records in place, and with little or no confidence in the food business management of food hygiene as indicated by Local Authority Inspectors' Confidence in Management scores.
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Affiliation(s)
- S K Sagoo
- Environmental Surveillance Unit, Health Protection Agency, Communicable Disease Surveillance Centre, 61 Colindale Avenue, London NW9 5EQ
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24
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Abstract
A microbiological study of ready-to-eat foods with added spices or spice ingredients was undertaken to identify any risk factors in the production, storage and display of this product and to establish their effect on microbiological quality. Examination of 1946 ready-to-eat foods from sandwich bars, cafés, public houses, restaurants, specialist sandwich producers, bakers, delicatessens, market stalls and mobile vendors found that 1291 (66%) were of satisfactory/acceptable microbiological quality, 609 (32%) were of unsatisfactory quality, and 46 (2%) were of unacceptable quality. Unacceptable results were due to high levels of B. cereus and/or other Bacillus spp. (>/=10(5) cfu g(-1)). Unsatisfactory results were mostly due to high Aerobic Colony Counts (up to >/=10(7) cfu g(-1)), Enterobacteriaceae (>/=10(4) cfu g(-1)), Escherichia coli (>/=10(2) cfu g(-1)), and Bacillus spp (>/=10(4) cfu g(-1)). Examination of 750 spices and spice ingredients revealed that B. cereus were present in 142 (19%) samples, other Bacillus spp. in 399 (53%) samples, and Salmonella spp. (S. enteritidis PT 11) in one (<1%) sample. Approximately a third (222) of spice and spice ingredients examined contained high counts (>/=10(4) cfu g(-1)) of B. cereus and/or other Bacillus spp., and appeared to be associated with the corresponding ready-to-eat foods containing similar high counts of these organisms (P<0.0001). Acceptable microbiological quality of ready-to-eat foods to which spices or spice ingredients have been added was associated with premises that had management food hygiene training and hazard analysis in place. Poor microbiological quality was associated with preparation on the premises, premises type, little or no confidence in the food business management of food hygiene, and small premises as indicated by local authority inspectors' confidence in management and consumer at risk scores.
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Affiliation(s)
- C L Little
- Environmental Surveillance Unit, Public Health Laboratory Service, London, UK.
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25
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Sagoo SK, Little CL, Ward L, Gillespie IA, Mitchell RT. Microbiological study of ready-to-eat salad vegetables from retail establishments uncovers a national outbreak of salmonellosis. J Food Prot 2003; 66:403-9. [PMID: 12636292 DOI: 10.4315/0362-028x-66.3.403] [Citation(s) in RCA: 122] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The increasing availability of bagged prepared salad vegetables reflects consumer demand for fresh, healthy, convenient, and additive-free foods that are safe and nutritious. During May and June 2001 a study of retail bagged prepared ready-to-eat salad vegetables was undertaken to determine the microbiological quality of these vegetables. Examination of the salad vegetables revealed that the vast majority (3,826 of 3,852 samples; 99.3%) were of satisfactory or acceptable microbiological quality according to Public Health Laboratory Service microbiological guidelines, while 20 (0.5%) samples were of unsatisfactory microbiological quality. Unsatisfactory quality was due to Escherichia coli and Listeria spp. (not Listeria monocytogenes) levels in excess of 10(2) CFU/g. However, six (0.2%) samples were of unacceptable microbiological quality because of the presence of Salmonella (Salmonella Newport PT33 [one sample], Salmonella Umbilo [three samples], and Salmonella Durban [one sample]) or because of a L. monocytogenes level of 660 CFU/g, which indicates a health risk. In each case, the retailer involved and the UK Food Standards Agency were immediately informed, and full investigations were undertaken. Nineteen cases of Salmonella Newport PT33 infection were subsequently identified throughout England and Wales. The outbreak strain of Salmonella Newport PT33 isolated from the salad and from humans had a unique plasmid profile. Campylobacter spp. and E. coli O157 were not detected in any of the samples examined. The presence of Salmonella, as well as high levels of L. monocytogenes, is unacceptable. However, minimally processed cut and packaged salad is exposed to a range of conditions during growth, harvest, preparation, and distribution, and it is possible that these conditions may increase the potential for microbial contamination, highlighting the necessity for the implementation of good hygiene practices from farm to fork to prevent contamination and/or bacterial growth in these salad products.
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Affiliation(s)
- S K Sagoo
- Environmental Surveillance Unit, Public Health Laboratory Service, Communicable Disease Surveillance Centre, 61 Colindale Avenue, London NW9 5EQ, UK
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26
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Ward LR, Maguire C, Hampton MD, de Pinna E, Smith HR, Little CL, Gillespie IA, O'Brien SJ, Mitchell RT, Sharp C, Swann RA, Doyle O, Threlfall EJ. Collaborative investigation of an outbreak of Salmonella enterica serotype Newport in England and Wales in 2001 associated with ready-to-eat salad vegetables. Commun Dis Public Health 2002; 5:301-4. [PMID: 12564245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
In June 2001, as part of a microbiological study of bagged, ready-to-eat salad products, Salmonella enterica serotype Newport was isolated from a sample of pre-packed green salad distributed by a major supermarket retailer. The strain was characterised by phage typing, plasmid profile typing and pulsed-field gel electrophoresis. Other isolates of S. Newport from cases of human infection in England and Wales in the first six months of 2001 were similarly characterised. Of 60 strains from cases of human infection, 19 were found to be indistinguishable from that isolated from the salad product. This study highlights the benefits of an integrated approach to outbreak investigations, involving the various elements of the PHLS and the Food Standards Agency, and acknowledges the full co-operation of the retailer in ensuring the rapid withdrawal of the contaminated product.
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Affiliation(s)
- L R Ward
- Laboratory of Enteric Pathogens, Public Health Laboratory Service, 61 Colindale Avenue, London NW9 5HT
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27
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Little CL, Barnes J, Mitchell RT. Microbiological quality of take-away cooked rice and chicken sandwiches: effectiveness of food hygiene training of the management. Commun Dis Public Health 2002; 5:289-98. [PMID: 12564243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
During August 2001 a microbiological study of ready-to-eat cooked rice from take-aways and of chicken sandwiches made on the premises from sandwich bars was undertaken. The intention was to identify risk factors in the production, storage and handling of cooked rice and sandwiches, and to establish their effect on microbiological quality. Examination of cooked rice revealed that the majority of samples (87%; 442 of 508) were of satisfactory/acceptable microbiological quality; 50 (10%) were unsatisfactory, and 16 (3%) were of unacceptable quality due to Bacillus cereus and/or other Bacillus spp in excess of 10(5) cfu/g. The microbiological quality of cooked rice was associated with cuisine type (p < 0.00001), rice type (p < 0.01), cooking (p < 0.01), serving methods (p < 0.00001), and management food hygiene training (p < 0.01). Examination of chicken sandwiches found that most (75%; 335 of 449) were of satisfactory/acceptable microbiological quality and 114 (25%) were unsatisfactory. Acceptable microbiological quality of sandwiches was associated with sandwich bars that had hazard analysis in place (p < 0.05). Smaller businesses, as indicated by Local Authority Inspectors' Consumer at Risk scores, were more likely to have samples classified as unsatisfactory or unacceptable compared to larger businesses (p < 0.001). The majority (90%) of premises had hand-washing facilities accessible and available for use, although only over half (55%) were correctly used as judged by the sampling officer. Where the manager of the premises had received some form of food hygiene training, food safety procedures such as the hazard analysis system were more likely to be in place (p < 0.0001).
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Affiliation(s)
- C L Little
- Environmental Surveillance Unit, Public Health Laboratory Service (CDSC), 61 Colindale Avenue, London NW9 5EQ.
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Little CL, Gillespie IA, Mitchell RT. Microbiological examination of ready-to-eat burgers sampled anonymously at the point of sale in the United Kingdom. Commun Dis Public Health 2001; 4:293-9. [PMID: 12109398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
During May and June 1999 a microbiological study of ready-to-eat burgers purchased anonymously from burger outlets (combined take-away and burger restaurants, take-away-only fixed premises, mobile vendors, temporary stalls and other burger outlets) was undertaken. The intention was to determine the microbiological quality of ready-to-eat burgers as purchased by customers of take-away premises and to ascertain, where information was available, whether the Chief Medical Officer's advice on cooking burgers was being followed. Examination of 3,128 ready-to-eat burgers found that 2,868 (92%) were of acceptable quality and 260 (8%) were of unsatisfactory quality. Unsatisfactory results were mostly due to high aerobic colony counts (ACCs). Salmonella spp., Campylobacter spp. and Escherichia coli O157 were not detected in any of the samples examined. Acceptable microbiological quality of ready-to-eat burgers was associated with outlets, such as combined take-away and burger restaurants and in particular national franchise outlets, which had management food hygiene training and hazard analysis in place. Poor microbiological quality was associated with undercooking and local outlets as indicated by Local Authority Inspectors' Consumers at Risk scores.
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Affiliation(s)
- C L Little
- Environmental Surveillance Unit, Public Health Laboratory Service, Communicable Disease Surveillance Centre (CDSC), 61 Colindale Avenue, London.
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Sagoo SK, Little CL, Mitchell RT. The microbiological examination of ready-to-eat organic vegetables from retail establishments in the United Kingdom. Lett Appl Microbiol 2001; 33:434-9. [PMID: 11737627 DOI: 10.1046/j.1472-765x.2001.01026.x] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIMS A microbiological study of uncooked ready-to-eat organic vegetables was undertaken to determine the microbiological quality of these vegetables on retail sale in the UK. METHODS AND RESULTS Organic vegetables were collected and examined according to a standardized protocol. The majority (3185 of 3200; 99.5%) of samples were found to be of satisfactory/acceptable quality whilst only 15 (0.5%) were of unsatisfactory quality. Unsatisfactory results were due to Escherichia coli and Listeria spp. (not L. monocytogenes) levels in excess of 102 cfu g-1. CONCLUSIONS The absence of pathogens (L. monocytogenes, Salmonella, Campylobacter and E. coli O157) and the low incidence (1.5%) of E. coli and Listeria spp. associated with these organic vegetables indicates that overall agricultural, hygiene, harvesting and production practices were good. SIGNIFICANCE AND IMPACT OF THE STUDY There has been a significant expansion of the UK organic market since 1998/99. Of the various commodity sectors making up the organic market, fruit and vegetables is the largest sector and this has been reflected in an increased interest in their microbiological safety. This is the first study to provide information on the microbiological quality of organic vegetables.
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Affiliation(s)
- S K Sagoo
- Environmental Surveillance Unit, Public Health Laboratory Service (CDSC), 61 Colindale Avenue, London NW9 5EQ, UK.
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Gillespie IA, Little CL, Mitchell RT. Microbiological examination of ready-to-eat quiche from retail establishments in the United Kingdom. Commun Dis Public Health 2001; 4:53-9. [PMID: 11467022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
A microbiological study of ready-to-eat quiche from retail establishments was undertaken to identify risk factors in the production, storage and handling of quiche and to establish their effect on microbiological quality. Examination of cold ready-to-eat quiche from supermarket and other delicatessens, bakers, butchers, cafés, sandwich bars and other retail premises revealed that most (2354 of 2513; 94%) were of acceptable quality; 157 samples (6%) were of unsatisfactory quality and two (< 1%) were unacceptable. Unsatisfactory results were mostly due to high aerobic colony counts. Unacceptable results were due to high levels (> 10(4) cfu/g) of Escherichia coli in two samples. Salmonella spp. were not detected in any of the samples. Satisfactory microbiological quality of ready-to-eat quiche was associated with premises that had management food hygiene training and hazard analysis in place. The microbiological quality of this food was also associated with premises type, quiche type, slicing and serving methods, and existing Local Authority Inspectors' Consumer at Risk scores.
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Affiliation(s)
- I A Gillespie
- PHLS Environmental Surveillance Unit, CDSC, Public Health Laboratory Service, 61 Colindale Avenue, London NW9 5EQ
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Abstract
Renal cell cancer is the main malignant tumour of the kidney and has an increasing incidence. This type of tumour has a poor prognosis and shows intrinsic resistance to several anti-cancer drugs. The CYP3A P450 family, which consists of three closely related forms, is involved in the oxidative activation and deactivation of a variety of carcinogens and several anti-cancer drugs. In this study the presence and cellular localization of CYP3A has been investigated using a combination of immunohistochemistry, immunoblotting and reverse transcriptase polymerase chain reaction (RT-PCR) in renal cell cancer and corresponding normal kidney. CYP3A was consistently expressed in both renal call cancer and in normal kidney. In renal cell cancer, CYP3A was localized to tumour cells and in normal kidney the predominant cellular localization of CYP3A was to proximal tubular epithelial cells. RT-PCR showed that both CYP3A5 mRNA and CYP3A7 mRNA were consistently present in both tumour and normal samples, while CYP3A4 mRNA was present in 65% of tumours and 90% of normal samples. This study indicates that individual members of the CYP3A family are expressed in renal cell cancer. The presence of CYP3A in renal cell cancer might be important in the metabolic potentiation as well as the detoxification of chemotherapeutic agents used to renal cancer.
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Affiliation(s)
- G I Murray
- Department of Pathology, University of Aberdeen, Foresterhill, UK
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Abstract
Ambulatory surgery is a successful venture for the health care system and the consumer. It provides many challenges and opportunities to keep our health care costs down while providing the patient with education and a concentration of care. This article describes the organization of a free-standing hospital-owned program and the basic policies and procedures that are required to ensure its quality.
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Mitchell RT, Deacon JW. DIFFERENTIAL (HOST-SPECIFIC) ACCUMULATION OF ZOOSPORES OF PYTHIUM ON ROOTS OF GRAMINACEOUS AND NON-GRAMINACEOUS PLANTS. New Phytol 1986; 102:113-122. [PMID: 33873888 DOI: 10.1111/j.1469-8137.1986.tb00803.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Zoospores of Pythium graminicola Subramanian and P. arrhenomanes Drechs., which characteristically infect the Gramineae, differed from spores of P. aphanidermatum (Edson) Fitzp. and P. ultimum Trow, which have wide host ranges, by accumulating to a greater degree on roots of graminaceous as compared with non-graminaceous plants. These differential responses occurred with wild plants collected from field sites or grown in a glasshouse, but not with cultivated cereals and dicotyledonous plants (Antirrhinum majus L. and Lycopersicon esculentum Mill.) grown in a glasshouse. Differential responses involved mainly encystment and accumulation of encysted spores, rather than taxis. Root mucigel was implicated in zoospore accumulation. Host-differences in this respect did not occur with damaged roots; treatment of roots with methylene blue or periodate (but not alcian blue or Calcofluor) prevented or reduced zoospore encystment without markedly affecting accumulation of motile zoospores.
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Affiliation(s)
- R T Mitchell
- Microbiology Department, School of Agriculture, West Mains Road, Edinburgh, EH9 3JG, UK
| | - J W Deacon
- Microbiology Department, School of Agriculture, West Mains Road, Edinburgh, EH9 3JG, UK
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Mitchell RT, Marshall LH, Lefkowitz LB, Stratton CW. Falsely elevated serum creatinine levels secondary to the presence of 5-fluorocytosine. Am J Clin Pathol 1985; 84:251-3. [PMID: 4025232 DOI: 10.1093/ajcp/84.2.251] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The Kodak Ektachem (Eastman Kodak Co., Rochester, NY) is a new clinical chemistry analyzer that uses an enzymatic method to measure creatinine. The authors report the case of a patient with falsely elevated creatinine levels that were caused by the presence of 5-fluorocytosine. A review of the literature confirmed that this can occur, but well documented reports are not found. In order to determine the magnitude of this interference, the authors plotted creatinine levels versus 5-FC concentration. Significant interference is seen with therapeutic levels of 5-FC. Both clinicians and pathologists should be aware of this phenomenon.
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35
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Greer JP, York JC, Cousar JB, Mitchell RT, Flexner JM, Collins RD, Stein RS. Peripheral T-cell lymphoma: a clinicopathologic study of 42 cases. J Clin Oncol 1984; 2:788-98. [PMID: 6376720 DOI: 10.1200/jco.1984.2.7.788] [Citation(s) in RCA: 102] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Clinical and histopathologic material from 42 patients with peripheral T-cell lymphoma (PTCL) was reviewed. The median age was 63.5 years (range, 11-97 years). The male:female ratio was 2.8:1. Prior immune or lymphoproliferative diseases occurred in 36% of the patients. PTCL was advanced at presentation with B symptoms (67%), generalized adenopathy (69%), and stage III/IV disease (79%). Suspected lung or pleural involvement (21%), hepatomegaly (29%), and splenomegaly (43%) were common; marrow involvement was documented in 37% of the patients at presentation and in 51% of patients during the illness. Hypercalcemia and eosinophilia occurred in 19% and 29% of patients, respectively. Among patients receiving combination chemotherapy (BCOP, CHOP, BACOP, COMLA), eight (24%) of 33 achieved a complete remission and only four (12%) of 33 had a sustained complete remission. The median survival for PTCL was 11 months. Because of the poor response to standard therapy, clinical trials should identify cases of PTCL and evaluate newer regimens in this subset of aggressive lymphoma.
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Tolson RH, Duxbury TC, Born GH, Christensen EJ, Diehl RE, Farless D, Hildebrand CE, Mitchell RT, Molko PM, Morabito LA, Palluconi FD, Reichert RJ, Taraji H, Veverka J, Neugebauer G, Findlay JT. Viking First Encounter of Phobos: Preliminary Results. Science 1978; 199:61-4. [PMID: 17841954 DOI: 10.1126/science.199.4324.61] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
During the last 2 weeks of February 1977, an intensive scientific investigation of the martian satellite Phobos was conducted by the Viking Orbiter-1 (VO-1) spacecraft. More than 125 television pictures were obtained during this period and infrared observations were made. About 80 percent of the illuminated hemisphere was imaged at a resolution of about 30 meters. Higher resolution images of limited areas were also obtained. Flyby distances within 80 kilometers of the surface were achieved. An estimate of the mass of Phobos (GM) was obtained by observing the effect of Phobos's gravity on the orbit of VO-1 as sensed by Earth-based radiometric tracking. Preliminary results indicate a value of GM of 0.00066 +/- 0.00012 cubic kilometer per second squared (standard deviation of 3) and a mean density of about 1.9 +/- 0.6 gram per cubic centimeter (standard deviation of 3). This low density, together with the low albedo and the recently determined spectral reflectance, suggest that Phobos is compositionally similar to type I carbonaceous chondrites. Thus, either this object formed in the outer part of the asteroid belt or Lewis's theory that such material cannot condense at 1.5 astronomical units is incorrect. The data on Phobos obtained during this first encounter period are comparable in quantity to all of the data on Mars returned by Mariner flights 4, 6, and 7.
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