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Habbous S, Barnieh L, Litchfield K, McKenzie S, Reich M, Lam NN, Mucsi I, Bugeja A, Yohanna S, Mainra R, Chong K, Fantus D, Prasad GVR, Dipchand C, Gill J, Getchell L, Garg AX. A RAND-Modified Delphi on Key Indicators to Measure the Efficiency of Living Kidney Donor Candidate Evaluations. Clin J Am Soc Nephrol 2020; 15:1464-1473. [PMID: 32972951 PMCID: PMC7536753 DOI: 10.2215/cjn.03780320] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [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: 03/23/2020] [Accepted: 07/16/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND AND OBJECTIVES Many patients, providers, and potential living donors perceive the living kidney donor evaluation process to be lengthy and difficult to navigate. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS We sought consensus on key terms and process and outcome indicators that can be used to measure how efficiently a transplant center evaluates persons interested in becoming a living kidney donor. Using a RAND-modified Delphi method, 77 participants (kidney transplant recipients or recipient candidates, living kidney donors or donor candidates, health care providers, and health care administrators) completed an online survey to define the terms and indicators. The definitions were then further refined during an in-person meeting with ten stakeholders. RESULTS We identified 16 process indicators (e.g., average time to evaluate a donor candidate), eight outcome indicators (e.g., annual number of preemptive living kidney donor transplants), and two measures that can be considered both process and outcome indicators (e.g., average number of times a candidate visited the transplant center for the evaluation). Transplant centers wishing to implement this set of indicators will require 22 unique data elements, all of which are either readily available or easily collected prospectively. CONCLUSIONS We identified a set of indicators through a consensus-based approach that may be used to monitor and improve the performance of a transplant center in how efficiently it evaluates persons interested in becoming a living kidney donor.
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Affiliation(s)
- Steven Habbous
- Department of Epidemiology and Biostatistics, Western University, London, Ontario, Canada .,Quality, Measurement, and Evaluation, Ontario Health (Cancer Care Ontario), Toronto, Ontario, Canada
| | - Lianne Barnieh
- Department of Nephrology, London Health Sciences Centre, London, Ontario, Canada
| | - Kenneth Litchfield
- Canadians Seeking Solutions and Innovations to Overcome Chronic Kidney Disease, Canada
| | - Susan McKenzie
- Canadians Seeking Solutions and Innovations to Overcome Chronic Kidney Disease, Canada
| | - Marian Reich
- Canadians Seeking Solutions and Innovations to Overcome Chronic Kidney Disease, Canada
| | - Ngan N Lam
- Division of Nephrology, University of Calgary, Calgary, Alberta, Canada
| | - Istvan Mucsi
- Kidney Transplant Program, University Health Network, Toronto, Ontario, Canada
| | - Ann Bugeja
- Division of Nephrology, The Ottawa Hospital, Ottawa, Ontario, Canada
| | - Seychelle Yohanna
- Division of Nephrology, McMaster University, Hamilton, Ontario, Canada
| | - Rahul Mainra
- Saskatchewan Transplant Program, Saskatoon Health Region, Saskatoon, Saskatchewan, Canada
| | - Kate Chong
- Canadians Seeking Solutions and Innovations to Overcome Chronic Kidney Disease, Canada
| | - Daniel Fantus
- Department of Medicine, Centre Hospitalier de l'Université de Montréal, Montreal, Quebec, Canada
| | - G V Ramesh Prasad
- Kidney Transplant Program, St. Michael's Hospital, Toronto, Ontario, Canada
| | - Christine Dipchand
- Division of Nephrology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Jagbir Gill
- Division of Nephrology, St. Paul's Hospital, Vancouver, British Columbia, Canada
| | - Leah Getchell
- Canadians Seeking Solutions and Innovations to Overcome Chronic Kidney Disease, Canada
| | - Amit X Garg
- Department of Epidemiology and Biostatistics, Western University, London, Ontario, Canada.,Department of Nephrology, London Health Sciences Centre, London, Ontario, Canada
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Sinajon P, Chitayat D, Roifman M, Wasim S, Carmona S, Ryan G, Noor A, Kolomietz E, Chong K. Microarray and RASopathy-disorder testing in fetuses with increased nuchal translucency. Ultrasound Obstet Gynecol 2020; 55:383-390. [PMID: 31115076 DOI: 10.1002/uog.20352] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 05/03/2019] [Accepted: 05/10/2019] [Indexed: 06/09/2023]
Abstract
OBJECTIVES To determine the incidence of chromosomal abnormalities, submicroscopic chromosomal abnormalities and RASopathy-disorder (RD) pathogenic variants in a cohort of pregnancies with nuchal translucency thickness (NT) ≥ 3.5 mm, and to propose a clinical protocol for surveillance of this group of patients. METHODS This was a retrospective chart review of patients referred to The Prenatal Diagnosis and Medical Genetics Program at Mount Sinai Hospital between January 2013 and December 2015, due to NT ≥ 3.5 mm, who underwent chorionic villus sampling or amniocentesis. Patients underwent extensive genetic counseling prior to invasive procedures and testing. Quantitative fluorescence polymerase chain reaction (QF-PCR) was performed as the first-line test for aneuploidy. If the result was negative, patients underwent karyotyping and/or chromosomal microarray analysis (CMA), and if the findings were normal, they had testing for RD pathogenic variants, which included nine known genes. Patients also underwent detailed fetal ultrasound examinations and echocardiography, performed by expert operators. RESULTS A total of 226 eligible patients were identified. In 116/226 (51.3%) patients, QF-PCR identified a chromosomal aneuploidy. The remaining 110/226 (48.7%) patients had further genetic testing. Karyotyping/CMA detected an abnormal/pathogenic cytogenetic result in 9/110 (8.2%) patients, as well as five variants of unknown significance (VOUS). RD testing yielded three pathogenic variants (3/103), giving a detection rate of 2.9%, and one VOUS. The optimal NT cut-off for RD screening was 7.9 mm in this population. In 92/110 (83.6%) patients, the genetic investigations were normal. Of these pregnancies, an early (14-16 weeks' gestation) detailed fetal ultrasound examination identified a structural abnormality in 24 (26.1%), 15 (16.3%) had an abnormal detailed ultrasound examination at 18-22 weeks' gestation and fetal echocardiography showed a cardiac abnormality in nine (9.8%). The birth outcome in the 83 pregnancies that had normal genetic investigations and known outcome included seven (8.4%) cases of termination of pregnancy, seven (8.4%) cases of intrauterine fetal death and 69 (83.1%) cases of live birth. Nine (9.8%) patients were lost to follow-up. CONCLUSIONS Both CMA and molecular testing for RD are important investigations in pregnancies with NT ≥ 3.5 mm. The use of genetic testing combined with fetal ultrasound examination provides valuable information that can influence pregnancy outcome, and provide recurrence risks, in this patient population. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.
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Affiliation(s)
- P Sinajon
- The Prenatal Diagnosis and Medical Genetics Program, Department of Obstetrics and Gynecology, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
- Division of Clinical and Metabolic Genetics, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
| | - D Chitayat
- The Prenatal Diagnosis and Medical Genetics Program, Department of Obstetrics and Gynecology, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
- Division of Clinical and Metabolic Genetics, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
| | - M Roifman
- The Prenatal Diagnosis and Medical Genetics Program, Department of Obstetrics and Gynecology, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
- Division of Clinical and Metabolic Genetics, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
| | - S Wasim
- University Health Network, Toronto, Ontario, Canada
| | - S Carmona
- Medical Informatics Information Services, Joseph and Wolf Lebovic Health Complex, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
| | - G Ryan
- Fetal Medicine Unit, Department of Obstetrics and Gynecology, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
| | - A Noor
- Division of Diagnostic Medical Genetics, Department of Pathology and Laboratory Medicine, Joseph and Wolf Lebovic Health Complex, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
| | - E Kolomietz
- Division of Diagnostic Medical Genetics, Department of Pathology and Laboratory Medicine, Joseph and Wolf Lebovic Health Complex, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
| | - K Chong
- The Prenatal Diagnosis and Medical Genetics Program, Department of Obstetrics and Gynecology, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
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Kim H, Park KJ, Ryu BK, Park DH, Kong DS, Chong K, Chae YS, Chung YG, Park SI, Kang SH. Forkhead box M1 (FOXM1) transcription factor is a key oncogenic driver of aggressive human meningioma progression. Neuropathol Appl Neurobiol 2019; 46:125-141. [PMID: 31179553 DOI: 10.1111/nan.12571] [Citation(s) in RCA: 17] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 06/04/2019] [Indexed: 12/11/2022]
Abstract
AIMS Aggressive meningioma remains incurable with neither chemo- nor targeted therapies proven effective, largely due to unidentified genetic alterations and/or aberrant oncogenic pathways driving the disease progression. In this study, we examined the expression and function of Forkhead box M1 (FOXM1) transcription factor during meningioma progression. METHODS Human meningioma samples (n = 101) were collected, followed by Western blotting, quantitative PCR, immunohistochemical and progression-free survival (PFS) analyses. For in vitro assays, FOXM1 was overexpressed or knocked-down in benign (SF4433 and SF4068) or malignant (SF3061 and IOMM-Lee) human meningioma cell lines respectively. For in vivo studies, siomycin A (a FOXM1 inhibitor)-pretreated or control IOMM-Lee cells were implanted subcutaneously in nude mice. RESULTS FOXM1 expression was increased in higher grades of meningioma and correlated with the mitotic index in the tumour tissue. Moreover, FOXM1 was increased in recurrent meningioma compared with the matched primary lesions. The patients who had higher FOXM1 expression had shorter PFS. In the subsequent in vitro assays, knockdown of FOXM1 in malignant meningioma cell lines resulted in decreased tumour cell proliferation, angiogenesis and invasion, potentially via regulation of β-catenin, cyclin D1, p21, interleukin-8, vascular endothelial growth factor-A, PLAU, and epithelial-to-mesenchymal transition-related genes, whereas overexpression of FOXM1 in benign meningioma cell lines had the opposite effects. Last, suppression of FOXM1 using a pharmacological inhibitor, siomycin A, decreased tumour growth in an in vivo mouse model. CONCLUSIONS Our data demonstrate that FOXM1 is a key transcription factor regulating oncogenic signalling pathways in meningioma progression, and a promising therapeutic target for aggressive meningioma.
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Affiliation(s)
- H Kim
- Department of Neurosurgery, Korea University Anam Hospital, Seoul, Korea
| | - K-J Park
- Department of Neurosurgery, Korea University Anam Hospital, Seoul, Korea
| | - B-K Ryu
- Department of Neurosurgery, Korea University Anam Hospital, Seoul, Korea
| | - D-H Park
- Department of Neurosurgery, Korea University Anam Hospital, Seoul, Korea
| | - D-S Kong
- Department of Neurosurgery, Samsung Medical Centre, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - K Chong
- Department of Neurosurgery, Korea University Anam Hospital, Seoul, Korea
| | - Y-S Chae
- Department of Pathology, Korea University College of Medicine, Seoul, Korea
| | - Y-G Chung
- Department of Neurosurgery, Korea University Anam Hospital, Seoul, Korea
| | - S I Park
- Department of Biochemistry and Molecular Biology, Korea University College of Medicine, Seoul, Korea.,The BK21 Plus Program, Korea University College of Medicine, Seoul, Korea.,Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, USA.,Vanderbilt Centre for Bone Biology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - S-H Kang
- Department of Neurosurgery, Korea University Anam Hospital, Seoul, Korea
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Levin A, Adams E, Barrett BJ, Beanlands H, Burns KD, Chiu HHL, Chong K, Dart A, Ferera J, Fernandez N, Fowler E, Garg AX, Gilbert R, Harris H, Harvey R, Hemmelgarn B, James M, Johnson J, Kappel J, Komenda P, McCormick M, McIntyre C, Mahmud F, Pei Y, Pollock G, Reich H, Rosenblum ND, Scholey J, Sochett E, Tang M, Tangri N, Tonelli M, Turner C, Walsh M, Woods C, Manns B. Canadians Seeking Solutions and Innovations to Overcome Chronic Kidney Disease (Can-SOLVE CKD): Form and Function. Can J Kidney Health Dis 2018; 5:2054358117749530. [PMID: 29372064 PMCID: PMC5774731 DOI: 10.1177/2054358117749530] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Accepted: 10/20/2017] [Indexed: 11/17/2022] Open
Abstract
PURPOSE OF REVIEW This article serves to describe the Can-SOLVE CKD network, a program of research projects and infrastructure that has excited patients and given them hope that we can truly transform the care they receive. ISSUE Chronic kidney disease (CKD) is a complex disorder that affects more than 4 million Canadians and costs the Canadian health care system more than $40 billion per year. The evidence base for guiding care in CKD is small, and even in areas where evidence exists, uptake of evidence into clinical practice has been slow. Compounding these complexities are the variations in outcomes for patients with CKD and difficulties predicting who is most likely to develop complications over time. Clearly these gaps in our knowledge and understanding of CKD need to be filled, but the current state of CKD research is not where it needs to be. A culture of clinical trials and inquiry into the disease is lacking, and much of the existing evidence base addresses the concerns of the researchers but not necessarily those of the patients. PROGRAM OVERVIEW The Canadian Institutes of Health Research (CIHR) has launched the national Strategy for Patient-Oriented Research (SPOR), a coalition of federal, provincial, and territorial partners dedicated to integrating research into care. Canadians Seeking Solutions and Innovations to Overcome Chronic Kidney Disease (Can-SOLVE CKD) is one of five pan-Canadian chronic kidney disease networks supported through the SPOR. The vision of Can-SOLVE CKD is that by 2020 every Canadian with or at high risk for CKD will receive the best recommended care, experience optimal outcomes, and have the opportunity to participate in studies with novel therapies, regardless of age, sex, gender, location, or ethnicity. PROGRAM OBJECTIVE The overarching objective of Can-SOLVE CKD is to accelerate the translation of knowledge about CKD into clinical research and practice. By focusing on the patient's voice and implementing relevant findings in real time, Can-SOLVE CKD will transform the care that CKD patients receive, and will improve kidney health for future generations.
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Affiliation(s)
- Adeera Levin
- The University of British Columbia, Vancouver, Canada
- BC Provincial Renal Agency, Vancouver, Canada
| | - Evan Adams
- The University of British Columbia, Vancouver, Canada
- First Nations Health Authority, West Vancouver, British Columbia, Canada
| | - Brendan J. Barrett
- Memorial University of Newfoundland, St. John’s, Newfoundland and Labrador, Canada
| | | | - Kevin D. Burns
- University of Ottawa, Ontario, Canada
- Ottawa Hospital Research Institute, Ontario, Canada
| | - Helen Hoi-Lun Chiu
- BC Provincial Renal Agency, Vancouver, Canada
- Providence Health Care Research Institute, Vancouver, British Columbia, Canada
- Can-SOLVE CKD Network, Vancouver, British Columbia, Canada
| | - Kate Chong
- Can-SOLVE CKD Network, Vancouver, British Columbia, Canada
| | - Allison Dart
- University of Manitoba, Winnipeg, Canada
- Children’s Hospital Research Institute of Manitoba, Winnipeg, Canada
| | - Jack Ferera
- Can-SOLVE CKD Network, Vancouver, British Columbia, Canada
| | | | | | - Amit X. Garg
- Western University, London, Ontario, Canada
- Institute for Clinical Evaluative Sciences, London, Ontario, Canada
| | - Richard Gilbert
- St. Michael’s Hospital, Toronto, Ontario, Canada
- University of Toronto, Ontario, Canada
| | - Heather Harris
- Providence Health Care Research Institute, Vancouver, British Columbia, Canada
- Can-SOLVE CKD Network, Vancouver, British Columbia, Canada
| | | | - Brenda Hemmelgarn
- University of Calgary, Alberta, Canada
- Foothills Medical Centre, Calgary, Alberta, Canada
- The Interdisciplinary Chronic Disease Collaboration, Calgary, Alberta, Canada
| | | | | | | | - Paul Komenda
- University of Manitoba, Winnipeg, Canada
- Seven Oaks General Hospital, Winnipeg, Manitoba, Canada
| | | | - Christopher McIntyre
- Western University, London, Ontario, Canada
- Lawson Health Research Institute, London, Ontario, Canada
| | - Farid Mahmud
- The Hospital for Sick Children, Toronto, Ontario, Canada
| | - York Pei
- University of Toronto, Ontario, Canada
- Toronto General Hospital, Ontario, Canada
- University Health Network, Toronto, Ontario, Canada
| | - Graham Pollock
- Providence Health Care Research Institute, Vancouver, British Columbia, Canada
- Can-SOLVE CKD Network, Vancouver, British Columbia, Canada
| | - Heather Reich
- University of Toronto, Ontario, Canada
- University Health Network, Toronto, Ontario, Canada
| | - Norman D. Rosenblum
- University of Toronto, Ontario, Canada
- The Hospital for Sick Children, Toronto, Ontario, Canada
| | - James Scholey
- University of Toronto, Ontario, Canada
- University Health Network, Toronto, Ontario, Canada
| | | | - Mila Tang
- BC Provincial Renal Agency, Vancouver, Canada
- Providence Health Care Research Institute, Vancouver, British Columbia, Canada
| | - Navdeep Tangri
- University of Manitoba, Winnipeg, Canada
- Seven Oaks General Hospital, Winnipeg, Manitoba, Canada
| | - Marcello Tonelli
- University of Calgary, Alberta, Canada
- The Interdisciplinary Chronic Disease Collaboration, Calgary, Alberta, Canada
| | | | - Michael Walsh
- McMaster University, Hamilton, Ontario, Canada
- Population Health Research Institute, Hamilton, Ontario, Canada
| | - Cathy Woods
- Can-SOLVE CKD Network, Vancouver, British Columbia, Canada
| | - Braden Manns
- University of Calgary, Alberta, Canada
- Foothills Medical Centre, Calgary, Alberta, Canada
- The Interdisciplinary Chronic Disease Collaboration, Calgary, Alberta, Canada
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Chang YK, Huang LF, Shin SJ, Lin KD, Chong K, Yen FS, Chang HY, Chuang SY, Hsieh TJ, Hsiung CA, Hsu CC. A Point-based Mortality Prediction System for Older Adults with Diabetes. Sci Rep 2017; 7:12652. [PMID: 28978911 PMCID: PMC5627261 DOI: 10.1038/s41598-017-12751-3] [Citation(s) in RCA: 7] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 09/15/2017] [Indexed: 02/07/2023] Open
Abstract
The mortality prediction models for the general diabetic population have been well established, but the corresponding elderly-specific model is still lacking. This study aims to develop a mortality prediction model for the elderly with diabetes. The data used for model establishment were derived from the nationwide adult health screening program in Taiwan in 2007-2010, from which we applied a 10-fold cross-validation method for model construction and internal validation. The external validation was tested on the MJ health screening database collected in 2004-2007. Multivariable Cox proportional hazards models were used to predict five-year mortality for diabetic patients ≥65 years. A total of 220,832 older subjects with diabetes were selected for model construction, of whom 23,241 (10.5%) died by the end of follow-up (December 31, 2011). The significant predictors retained in the final model included age, gender, smoking status, body mass index (BMI), fasting glucose, systolic and diastolic blood pressure, leukocyte count, liver and renal function, total cholesterol, hemoglobin, albumin, and uric acid. The Harrell's C in the development, internal-, and external-validation datasets were 0.737, 0.746, and 0.685, respectively. We established an easy-to-use point-based model that could accurately predict five-year mortality risk in older adults with diabetes.
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Affiliation(s)
- Y K Chang
- Department of Medical Research, Tung's Taichung MetroHarbor Hospital, Taichung, Taiwan
| | - L F Huang
- Institute of Population Health Sciences, National Health Research Institutes, Zhunan, Taiwan
| | - S J Shin
- College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
- Ditvision of Endocrinology and Metabolism, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
- Department of Internal Medicine, Kaohsiung Municipal Ta-Tung Hospital, Kaohsiung, Taiwan
| | - K D Lin
- College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
- Ditvision of Endocrinology and Metabolism, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
- Department of Internal Medicine, Kaohsiung Municipal Ta-Tung Hospital, Kaohsiung, Taiwan
| | - K Chong
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Min-Sheng General Hospital, Taoyuan, Taiwan
| | - F S Yen
- Dr. Yen's Clinic, Taoyuan, Taiwan
| | - H Y Chang
- Institute of Population Health Sciences, National Health Research Institutes, Zhunan, Taiwan
| | - S Y Chuang
- Institute of Population Health Sciences, National Health Research Institutes, Zhunan, Taiwan
| | - T J Hsieh
- Institute of Population Health Sciences, National Health Research Institutes, Zhunan, Taiwan
| | - C A Hsiung
- Institute of Population Health Sciences, National Health Research Institutes, Zhunan, Taiwan
| | - C C Hsu
- Institute of Population Health Sciences, National Health Research Institutes, Zhunan, Taiwan.
- Department of Health Services Administration, China Medical University, Taichung, Taiwan.
- Department of Family Medicine, Min-Sheng General Hospital, Taoyuan, Taiwan.
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Wou K, Hyun Y, Chitayat D, Vlasschaert M, Chong K, Wasim S, Keating S, Shannon P, Kolomietz E. Analysis of tissue from products of conception and perinatal losses using QF-PCR and microarray: A three-year retrospective study resulting in an efficient protocol. Eur J Med Genet 2016; 59:417-24. [PMID: 27233578 DOI: 10.1016/j.ejmg.2016.05.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [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: 09/02/2015] [Revised: 05/16/2016] [Accepted: 05/21/2016] [Indexed: 11/15/2022]
Abstract
OBJECTIVE To evaluate the performance of a laboratory protocol for direct genetic analysis performed on tissues obtained from miscarriages, stillbirth and postnatal death. METHODS Samples were collected between July 1st, 2011 and June 30th, 2014. QF-PCR analysis was the initial test followed by aCGH analysis performed on the normal QF-PCR specimens. RESULTS Of the 1195 submitted specimens, a total of 1071 samples were confirmed as true fetal. The failure rate was 1.4%. Of those, 30.8% yielded abnormal results. Of the latter, 57.6% had abnormal QF-PCR and 42.4% had abnormal microarray result. Autosomal trisomies were detected in 61.2%, triploidy in 7.6%, monosomy X in 9.1%, sex-chromosome aneuploidy (apart from monosomy X) in 1.5%, molar pregnancies in 5.8% and copy number variants in 14.2% including microdeletions/microduplications and cryptic unbalanced rearrangements. The highest diagnostic yield was observed in the 1st trimester specimens at 67.6%. We confirmed that maternal age correlates with the likelihood of autosomal trisomies but not with triploidy, sex chromosome aneuploidies, molar pregnancy, or CNVs. CONCLUSION An efficient laboratory protocol, based on QF-PCR and aCGH of uncultured cells has replaced standard cytogenetic analysis in testing of tissue from all pregnancy losses in our center and resulted in reduced test failure rate and increased diagnostic yield.
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Affiliation(s)
- K Wou
- Department of Obstetrics and Gynecology, Division of Maternal Fetal Medicine, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Y Hyun
- Department of Pathology and Laboratory Medicine, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
| | - D Chitayat
- Department of Obstetrics and Gynecology, Division of Maternal Fetal Medicine, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada; The Prenatal Diagnosis and Medical Genetics Program, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada; Department of Pediatrics, Division of Clinical and Metabolic Genetics, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
| | - M Vlasschaert
- Department of Pathology and Laboratory Medicine, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
| | - K Chong
- Department of Obstetrics and Gynecology, Division of Maternal Fetal Medicine, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada; The Prenatal Diagnosis and Medical Genetics Program, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada; Department of Pediatrics, Division of Clinical and Metabolic Genetics, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
| | - S Wasim
- Department of Pediatrics, Division of Clinical and Metabolic Genetics, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada; Department of Internal Medicine, Division of Clinical and Metabolic Genetics, University Health Network, Toronto, Ontario, Canada
| | - S Keating
- Department of Pathology and Laboratory Medicine, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
| | - P Shannon
- Department of Pathology and Laboratory Medicine, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
| | - E Kolomietz
- Department of Pathology and Laboratory Medicine, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada.
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7
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Rosenfeld JA, Tucker ME, Escobar LF, Neill NJ, Torchia BS, McDaniel LD, Schultz RA, Chong K, Chitayat D. Diagnostic utility of microarray testing in pregnancy loss. Ultrasound Obstet Gynecol 2015; 46:478-486. [PMID: 25846569 DOI: 10.1002/uog.14866] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Revised: 03/25/2015] [Accepted: 03/29/2015] [Indexed: 06/04/2023]
Abstract
OBJECTIVES To determine the frequency of clinically significant chromosomal abnormalities identified by chromosomal microarray in pregnancy losses at any gestational age and to compare microarray performance with that of traditional cytogenetic analysis when testing pregnancy losses. METHODS Among 535 fetal demise specimens of any gestational age, clinical microarray-based comparative genomic hybridization (aCGH) was performed successfully on 515, and a subset of 107 specimens underwent additional single nucleotide polymorphism (SNP) analysis. RESULTS Overall, clinically significant abnormalities were identified in 12.8% (64/499) of specimens referred with normal or unknown karyotypes. Detection rates were significantly higher with earlier gestational age. In the subset with normal karyotype, clinically significant abnormalities were identified in 6.9% (20/288). This detection rate did not vary significantly with gestational age, suggesting that, unlike aneuploidy, the contribution of submicroscopic chromosomal abnormalities to fetal demise does not vary with gestational age. In the 107 specimens that underwent aCGH and SNP analysis, seven cases (6.5%) had abnormalities of potential clinical significance detected by the SNP component, including female triploidy. aCGH failed to yield fetal results in 8.3%, which is an improvement over traditional cytogenetic analysis of fetal demise specimens. CONCLUSIONS Both the provision of results in cases in which karyotype fails and the detection of abnormalities in the presence of a normal karyotype demonstrate the increased diagnostic utility of microarray in pregnancy loss. Thus, chromosomal microarray testing is a preferable, robust method of analyzing cases of pregnancy loss to better delineate possible genetic etiologies, regardless of gestational age.
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Affiliation(s)
- J A Rosenfeld
- Signature Genomic Laboratories, PerkinElmer, Inc., Spokane, WA, USA
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - M E Tucker
- St. Vincent Hospital, Indianapolis, IN, USA
| | | | - N J Neill
- Signature Genomic Laboratories, PerkinElmer, Inc., Spokane, WA, USA
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - B S Torchia
- Signature Genomic Laboratories, PerkinElmer, Inc., Spokane, WA, USA
| | - L D McDaniel
- Signature Genomic Laboratories, PerkinElmer, Inc., Spokane, WA, USA
| | - R A Schultz
- Signature Genomic Laboratories, PerkinElmer, Inc., Spokane, WA, USA
| | - K Chong
- The Prenatal Diagnosis and Medical Genetics Program, Mount Sinai Hospital, University of Toronto, Ontario, Canada
| | - D Chitayat
- The Prenatal Diagnosis and Medical Genetics Program, Mount Sinai Hospital, University of Toronto, Ontario, Canada
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Algazi AP, Cha E, Ortiz-Urda SM, McCalmont T, Bastian BC, Hwang J, Pampaloni MH, Behr S, Chong K, Cortez B, Quiroz A, Coakley F, Liu S, Daud AI. The combination of axitinib followed by paclitaxel/carboplatin yields extended survival in advanced BRAF wild-type melanoma: results of a clinical/correlative prospective phase II clinical trial. Br J Cancer 2015; 112:1326-31. [PMID: 25867272 PMCID: PMC4402449 DOI: 10.1038/bjc.2014.541] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 07/22/2014] [Accepted: 09/08/2014] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Simultaneous chemotherapy with vascular endothelial growth factor (VEGF) inhibition has not shown additional benefit over chemotherapy alone in advanced melanoma. We tested administration of the potent VEGF inhibitor axitinib followed by paclitaxel/carboplatin to determine whether enhanced tumour proliferation during axitinib withdrawal leads to sustained chemosensitivity. METHODS We conducted a prospective phase II trial in metastatic melanoma patients with ECOG performance status 0-1 and normal organ function. Axitinib 5 mg PO b.i.d. was taken on days 1-14 of each 21-day treatment cycle, and carboplatin (AUC=5) with paclitaxel (175 mg m(-2)) was administered on day 1 starting with cycle 2. 3'-Deoxy-3'-(18)F-fluorothymidine ((18)F-FLT)-PET scans were performed in five patients to assess tumour proliferation on days 1, 14, 17, and 20 of cycle 1. Molecular profiling for BRAF was performed for all patients with cutaneous, acral, or mucosal melanoma. RESULTS The treatment was well tolerated. The most common grade 3 AEs were hypertension, neutropenia, and anaemia. Grade 4 non-haematologic AEs were not observed. Four of five patients completing (18)F-FLT-PET scans showed increases (23-92%) in SUV values during the axitinib holiday. Of 36 evaluable patients, there were 8 confirmed PRs by Response Evaluation Criteria in Solid Tumors. Overall, 20 patients had SD and 8 had PD as the best response. The median PFS was 8.7 months and the median overall survival was 14.0 months. Five BRAF(V600E/K) patients had significantly worse PFS than patients without these mutations. CONCLUSIONS Axitinib followed by carboplatin and paclitaxel was well tolerated and effective in BRAF wild-type metastatic melanoma. 3'-Deoxy-3'-(18)F-fluorothymidine-PET scans showed increased proliferation during axitinib withdrawal.
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Affiliation(s)
- A P Algazi
- Department of Medicine, Division of Hematology/Oncology, University of California, 1600 Divisadero St MTZ-A741, San Francisco, CA 94143-1770, USA
| | - E Cha
- Department of Medicine, Division of Hematology/Oncology, University of California, 1600 Divisadero St MTZ-A741, San Francisco, CA 94143-1770, USA
| | - S M Ortiz-Urda
- Department of Dermatology, University of California, 1600 Divisadero St MTZ-A741, San Francisco, CA 94143-1770, USA
| | - T McCalmont
- Department of Dermatology, University of California, 1600 Divisadero St MTZ-A741, San Francisco, CA 94143-1770, USA
| | - B C Bastian
- Department of Dermatology, University of California, 1600 Divisadero St MTZ-A741, San Francisco, CA 94143-1770, USA
| | - J Hwang
- Department of Medicine, Division of Hematology/Oncology, University of California, 1600 Divisadero St MTZ-A741, San Francisco, CA 94143-1770, USA
| | - M H Pampaloni
- Department of Nuclear Medicine, University of California, 1600 Divisadero St MTZ-A741, San Francisco, CA 94143-1770, USA
| | - S Behr
- Department of Nuclear Medicine, University of California, 1600 Divisadero St MTZ-A741, San Francisco, CA 94143-1770, USA
| | - K Chong
- Department of Dermatology, University of California, 1600 Divisadero St MTZ-A741, San Francisco, CA 94143-1770, USA
| | - B Cortez
- Department of Medicine, Division of Hematology/Oncology, University of California, 1600 Divisadero St MTZ-A741, San Francisco, CA 94143-1770, USA
| | - A Quiroz
- Department of Medicine, Division of Hematology/Oncology, University of California, 1600 Divisadero St MTZ-A741, San Francisco, CA 94143-1770, USA
| | - F Coakley
- Department of Radiology, University of California, 1600 Divisadero St MTZ-A741, San Francisco, CA 94143-1770, USA
| | - S Liu
- Department of Radiology, University of California, 1600 Divisadero St MTZ-A741, San Francisco, CA 94143-1770, USA
| | - A I Daud
- Department of Medicine, Division of Hematology/Oncology, University of California, 1600 Divisadero St MTZ-A741, San Francisco, CA 94143-1770, USA
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Dempsey MA, Knight Johnson AE, Swope BS, Moldenhauer JS, Sroka H, Chong K, Chitayat D, Briere L, Lyon H, Palmer N, Gopalani S, Siebert JR, Lévesque S, Leblanc J, Menzies D, Haverfield E, Das S. Molecular confirmation of nine cases of Cornelia de Lange syndrome diagnosed prenatally. Prenat Diagn 2013; 34:163-7. [PMID: 24218399 DOI: 10.1002/pd.4279] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Revised: 11/01/2013] [Accepted: 11/05/2013] [Indexed: 12/24/2022]
Abstract
OBJECTIVES Cornelia de Lange syndrome (CdLS) is characterized by distinct facial features, growth retardation, upper limb reduction defects, hirsutism, and intellectual disability. NIPBL mutations have been identified in approximately 60% of patients with CdLS diagnosed postnatally. Prenatal ultrasound findings include upper limb reduction defects, intrauterine growth restriction, and micrognathia. CdLS has also been associated with decreased PAPP-A and increased nuchal translucency (NT). We reviewed NIPBL sequence analysis results for 12 prenatal samples in our laboratory to determine the frequency of mutations in our cohort. METHODS This retrospective study analyzed data from all 12 prenatal cases with suspected CdLS, which were received by The University of Chicago Genetic Services Laboratories. Diagnostic NIPBL sequencing was performed for all samples. Clinical information was collected from referring physicians. RESULTS NIPBL mutations were identified in 9 out of the 12 cases prenatally (75%). Amongst the NIPBL mutation-positive cases with clinical information available, the most common findings were upper limb malformations and micrognathia. Five patients had NT measurements in the first trimester, of which four were noted to be increased. CONCLUSION We demonstrate that prenatally-detected phenotypes of CdLS, particularly severe micrognathia and bilateral upper limb defects, are associated with an increased frequency of NIPBL mutations.
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Affiliation(s)
- M A Dempsey
- Human Genetics, The University of Chicago, Chicago, IL, USA
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Nikolic M, Lok L, Mattishent K, Barth S, Yung B, Cummings N, Shulgina L, Wade D, Shittu M, Vali Y, Chong K, Wilkinson A, Mikolasch T, Brij S, Jenkins S, Kamath A, Pasteur M, Wason J, Marciniak SJ. S82 Multi-centre prospective comparison of the BTS and ACCP guidelines to determine size in primary spontaneous pneumothorax. Thorax 2013. [DOI: 10.1136/thoraxjnl-2013-204457.89] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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11
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Currie A, Chong K, Davies GL. Using therapeutic mammoplasty to extend the role of breast-conserving surgery in women with larger or ptotic breasts. Ann R Coll Surg Engl 2013; 95:192-5. [PMID: 23827290 DOI: 10.1308/003588413x13511609958091] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
INTRODUCTION The equivalence of breast-conserving surgery followed by postoperative radiotherapy against mastectomy is now firmly established in patients with early breast cancer. The results of surgery in large-breasted women can be poor, with radiation-induced fibrosis, chronic pain and poor cosmesis contributing to long-term psychological and physical morbidity. Therapeutic mammoplasty offers an alternative management strategy to both enhance the role of breast-conserving surgery and provide better outcomes. METHODS A retrospective note review was undertaken of all patients undergoing therapeutic mammoplasty for breast malignancy between 2007 and 2011. All cases were performed using a Wise pattern-reduction technique. Histology and pathological outcomes were assessed. Postoperative outcomes reviewed included wound infection, seroma and need for further intervention. RESULTS During the study period, 20 patients underwent therapeutic mammoplasty with a mean follow-up duration of 36 months. The mean weight of the lumpectomy specimen was 330g. The average cancer size was 34mm, with a mean margin clearance of 7mm. There was one episode of wound infection and three of delayed wound healing at the T-junction. One patient required a mastectomy for involved margins. There were no recurrences at the most recent follow-up visit. CONCLUSIONS Therapeutic mammoplasty offers a tailored approach to women with larger breasts and early breast cancers with good cosmetic results and oncological outcomes.
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Affiliation(s)
- A Currie
- Department of Breast Surgery, Kingston Hospital, Galsworthy Road, Kingston upon Thames, Surrey KT2 7QB, UK.
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12
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Dixon JB, Hur KY, Lee WJ, Kim MJ, Chong K, Chen SC, Straznicky NE, Zimmet P. Gastric bypass in Type 2 diabetes with BMI < 30: weight and weight loss have a major influence on outcomes. Diabet Med 2013; 30:e127-34. [PMID: 23278432 DOI: 10.1111/dme.12107] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2012] [Revised: 11/12/2012] [Accepted: 12/18/2012] [Indexed: 12/22/2022]
Abstract
AIM To assess factors influencing glycaemic control following gastric bypass surgery in patients with Type 2 diabetes and BMI< 30 kg/m(2) . METHODS Prospective longitudinal study of 103 patients with inadequate glycaemic control who underwent gastric bypass surgery at Soonchunhyang University, Seoul, Korea (n = 66) and Min-Sheng General Hospital, Taipei, Taiwan (n = 37). Procedures were performed August 2009 to January 2011. Key outcome measures were excellent glycaemic control of Type 2 diabetes defined as HbA1c < 42 mmol/mol (≤6%); inadequate response defined as HbA1c > 53 mmol/mol (> 7%). Analysis was conducted using binary logistic regression, and cut-points obtained from receiver operator characteristics. RESULTS Excellent glycaemic control was achieved in 31 (30%) at 1 year. Diabetes duration of < 7 years and BMI > 27 kg/m(2) provided independent predictors and useful cut-points. Likelihood of excellent glycaemic control for an individual could be estimated using loge (Odds) = -6.7 + (0.26 × BMI) + (-1.2 × diabetes duration). Baseline BMI of < 27 kg/m(2) and baseline C-peptide of < 2.0ng/ml, best predicted a poor glycaemic response. In those with favourable baseline characteristics percentage weight loss (%WL) had a dominant influence on glycaemic outcomes. Baseline C-peptide (> 2.4 ng/ml) and subsequent percentage weight loss (> 16%) were associated with excellent glycaemic control. Higher BMI was associated with greater percentage weight loss. CONCLUSION In patients with Type 2 diabetes and BMI < 30 kg/m(2) , glycaemic response to gastric bypass is predicted by higher baseline BMI, shorter disease duration and higher fasting C-peptide. Post-surgery weight loss has a dominant effect. Baseline BMI and weight loss have a major influence on outcomes.
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Affiliation(s)
- J B Dixon
- Baker IDI Heart & Diabetes Institute, Melbourne, Victoria, Australia
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Sherbaf FG, Lee C, Woo X, Bertrand D, Inaki K, Chong K, Morton D, Huang S, Hoon D, Liu E. 585 Genomics of Metastatic Progression in Cutaneous Melanoma. Eur J Cancer 2012. [DOI: 10.1016/s0959-8049(12)71242-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Currie A, Chong K, Davies GL, Cummins RS. Ultrasonic dissection versus electrocautery in mastectomy for breast cancer - a meta-analysis. Eur J Surg Oncol 2012; 38:897-901. [PMID: 22704049 DOI: 10.1016/j.ejso.2012.05.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Accepted: 05/17/2012] [Indexed: 10/28/2022] Open
Abstract
BACKGROUND Electrocautery has advanced the practice of mastectomy but significant morbidity, such as seroma and blood loss, remains a concern. This has led to newer forms of dissection being introduced including the ultrasonic dissection devices, which are thought to reduce tissue damage. The aim of this systematic review was to compare the outcomes after mastectomy using novel ultrasonic dissection or standard electrocautery in published trials. METHODS Medline, Embase, trial registries, conference proceedings and reference lists were searched for comparative trials of ultrasonic dissection versus electrocautery for mastectomy. The primary outcomes were total postoperative drainage, seroma development and intra-operative blood loss. Secondary outcomes were operative time and wound complications. Odds ratios were calculated for categorical outcomes and standardised mean differences for continuous outcomes. RESULTS Six trials were included in the analysis of 287 mastectomies. There was no effect in total postoperative drainage (pooled analysis weight mean difference: -0.21 (95% CI: -0.70-0.29); p = 0.41) or seroma development (pooled analysis odds ratio: 0.77 (95% CIs 0.43-1.37); p = 0.37). Intra-operative blood was slightly less for ultrasonic dissection compared to standard electrocautery (pooled analysis weight mean difference: -1.04 (95% CI: -2.00 to -0.08); p = 0.03). Ultrasonic dissection and standard electrocautery had similar outcomes with regard to operative time and wound complications. CONCLUSION Ultrasonic dissection and standard electrocautery appear to deliver similar results in the mastectomy setting. Further cost-effectiveness analysis may guide surgeon selection in the use of new technologies for mastectomy.
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Affiliation(s)
- A Currie
- Department of Breast Surgery, Kingston Hospital, Galsworthy Road, Kingston-upon-Thames, Surrey KT2 7QB, UK.
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15
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Huynh KT, Takei Y, Kuo C, Scolyer RA, Murali R, Chong K, Takeshima L, Sim MS, Morton DL, Turner RR, Thompson JF, Hoon DSB. Aberrant hypermethylation in primary tumours and sentinel lymph node metastases in paediatric patients with cutaneous melanoma. Br J Dermatol 2012; 166:1319-26. [PMID: 22293026 DOI: 10.1111/j.1365-2133.2012.10867.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND Debate on how to manage paediatric patients with cutaneous melanoma continues, particularly in those with sentinel lymph node (SLN) metastases who are at higher risk of poor outcomes. Management is often based on adult algorithms, although differences in clinical outcomes between paediatric and adult patients suggest that melanoma in paediatric patients differs biologically. Yet, there are no molecular prognostic studies identifying these differences. OBJECTIVES We investigated the epigenetic (methylation) regulation of several tumour-related genes (TRGs) known to be significant in adult melanoma progression in histopathology(+) SLN metastases (n = 17) and primary tumours (n = 20) of paediatric patients with melanoma to determine their clinical relevance. METHODS Paediatric patients (n = 37; ≤ 21 years at diagnosis) with American Joint Committee on Cancer stage I-III cutaneous melanoma were analysed. Gene promoter methylation of the TRGs RASSF1A, RARβ2, WIF1 and APC was evaluated. RESULTS Hypermethylation of RASSF1A, RARβ2, WIF1 and APC was found in 29% (5/17), 25% (4/16), 25% (4/16) and 19% (3/16) of histopathology(+) SLNs, respectively. When matched to adult cutaneous melanomas by Breslow thickness and ulceration, hypermethylation of all four TRGs in SLN(+) paediatric patients with melanoma was equivalent to or less than in adults. With a median follow-up of 55 months, SLN(+) paediatric patients with melanoma with hypermethylation of > 1 TRG vs. ≤ 1 TRG had worse disease-free (P = 0·02) and overall survival (P = 0·02). CONCLUSIONS Differences in the methylation status of these TRGs in SLN(+) paediatric and adult patients with melanoma may account for why SLN(+) paediatric patients have different clinical outcomes. SLN biopsy should continue to be performed; within SLN(+) paediatric patients with melanoma, hypermethylation of TRGs can be used to identify a subpopulation at highest risk for poor outcomes who warrant vigilant clinical follow-up.
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Affiliation(s)
- K T Huynh
- Department of Molecular Oncology, John Wayne Cancer Institute, Santa Monica, CA 90404, USA
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Morgan AT, Liégeois F, Liederkerke C, Vogel AP, Hayward R, Harkness W, Chong K, Vargha-Khadem F. Role of cerebellum in fine speech control in childhood: persistent dysarthria after surgical treatment for posterior fossa tumour. Brain Lang 2011; 117:69-76. [PMID: 21334735 DOI: 10.1016/j.bandl.2011.01.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2010] [Revised: 12/03/2010] [Accepted: 01/23/2011] [Indexed: 05/30/2023]
Abstract
Dysarthria following surgical resection of childhood posterior fossa tumour (PFT) is most commonly documented in a select group of participants with mutism in the acute recovery phase, thus limiting knowledge of post-operative prognosis for this population of children as a whole. Here we report on the speech characteristics of 13 cases seen long-term after surgical treatment for childhood PFT, unselected for the presence of post-operative mutism (mean time post-surgery=6y10m, range 1;4-12;6 years, two had post-operative mutism), and examine factors affecting outcome. Twenty-six age- and sex- matched healthy controls were recruited for comparison. Participants in both groups had speech assessments using detailed perceptual and acoustic methods. Over two-thirds of the group (69%) with removal of PFT had a profile of typically mild dysarthria. Prominent speech deficits included consonant imprecision, reduced rate, monopitch and monoloudness. We conclude that speech deficits may persist even up to 10 years post-surgery in participants who have not shown mutism in the acute phase. Of cases with unilateral lesions, poorer outcomes were associated with right cerebellar tumours compared to left, consistent with the notion based on adult data that speech is controlled by reciprocal right cerebellar/left frontal interactions. These results confirm the important role of the cerebellum in the control of fine speech movements in children.
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Affiliation(s)
- A T Morgan
- Developmental Cognitive Neuroscience Unit, University College London Institute of Child Health, London, United Kingdom.
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Abstract
A high-throughput screening technique has been developed and was utilized in the discovery of a new n-type oxide possessing good thermoelectric properties. Screening of metal binary systems consisting of 3d transition metals using this technique showed LaNiO3 to possess the desired n-type properties. Electrical resistivity (ρ) of this oxide is favorably quite low, however, the Seebeck coefficient (S) is as small as –25 μV/K. To enhance the thermoelectric properties of LaNiO3, high-throughput screening was employed to examine candidates from the metal ternary La1–xMxNiO3 and LaNi1–xNxO3 systems. Bi substitution in the La1–xMxNiO3 systems and Cu substitution in the LaNi1–xNxO3 systems were found to be effective for improvement of S and ρ respectively.
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Mir R, Chong K, Benett C, Aldin A, Balen F, Kraus A, Taylor R. CP6 Anopthalmia and dysembryoplastic neuroepithelial tumours in a family with Noonan syndrome and a novel PTPN11 mutation. J Neurol Psychiatry 2010. [DOI: 10.1136/jnnp.2010.226340.71] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Abstract
AIMS The aim of this study was to develop and refine a decision rule on when to undertake brain imaging (BI) in neurologically normal children with headaches. METHODS From the literature and a questionnaire study, a list of red flags (RFs) was drawn-up. During the prospective 4-year period, consecutive children with headache were classified according to RFs and the headache diagnosis. RESULT Three of 709 (0.4%) neurologically normal children had significant brain abnormalities. BI was carried out in 389 of 498 (78%) children with RFs. Significant abnormalities were found in three of 389 children (0.8%), all had unclassified headache (UH). BI was not arranged for the 211 children with no RFs. None of these developed RFs or abnormal signs on follow-up for a mean of 13 months. CONCLUSION In addition to BI for those with neurological signs, we think BI should be considered for neurologically normal patients with UH and RFs. This would have saved imaging children needlessly: only 101 of 709 (14%) would have had scans arranged, instead of 389 of 709.
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Affiliation(s)
- M A S Ahmed
- Paediatric Department, Queen's University Hospital, London, UK.
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Rodrigues E, Chong K, Holmes A, Cannon R, Ruske D, Dawes P. Anin-vitrodevice for the assessment of biofilm mediated voice prosthesis damage: how we do it. Clin Otolaryngol 2009; 34:481-4. [DOI: 10.1111/j.1749-4486.2009.01996.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Goobie S, Knijnenburg J, Fitzpatrick D, Sharkey FH, Lionel AC, Marshall CR, Azam T, Shago M, Chong K, Mendoza-Londono R, den Hollander NS, Ruivenkamp C, Maher E, Tanke HJ, Szuhai K, Wintle RF, Scherer SW. Molecular and clinical characterization of de novo and familial cases with microduplication 3q29: guidelines for copy number variation case reporting. Cytogenet Genome Res 2009; 123:65-78. [PMID: 19287140 DOI: 10.1159/000184693] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/11/2008] [Indexed: 11/19/2022] Open
Abstract
Microdeletions of 3q29 have previously been reported, but the postulated reciprocal microduplication has only recently been observed. Here, cases from four families, two ascertained in Toronto (Canada) and one each from Edinburgh (UK) and Leiden (Netherlands), carrying microduplications of 3q29 are presented. These families have been characterized by cytogenetic and molecular techniques, and all individuals have been further characterized with genome-wide, high density single nucleotide polymorphism (SNP) arrays run at a single centre (The Centre for Applied Genomics, Toronto). In addition to polymorphic copy-number variants (CNV), all carry duplications of 3q29 ranging in size from 1.9 to 2.4 Mb, encompassing multiple genes and defining a minimum region of overlap of about 1.6 Mb bounded by clusters of segmental duplications that is remarkably similar in location to previously reported 3q29 microdeletions. Consistent with other reports, the phenotype is variable, although developmental delay and significant ophthalmological findings were recurrent, suggesting that dosage sensitivity of genes located within 3q29 is important for eye and CNS development. We also consider CNVs found elsewhere in the genome for their contribution to the phenotype. We conclude by providing preliminary guidelines for management and anticipatory care of families with this microduplication, thereby establishing a standard for CNV reporting.
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Affiliation(s)
- S Goobie
- Division of Clinical and Metabolic Genetics, The Hospital for Sick Children, Toronto, Ont., Canada
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Rohrbach M, Chitayat D, Maegawa G, Shanske S, Davidzon G, Chong K, Clarke J, Toi A, Tarnopolsky M, Robinson B, Blaser S. Intracerebral Periventricular Pseudocysts in a Fetus with Mitochondrial Depletion Syndrome: An Association or Coincidence. Fetal Diagn Ther 2009; 25:177-82. [DOI: 10.1159/000209385] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2007] [Accepted: 04/07/2008] [Indexed: 11/19/2022]
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Johnson N, Windrim R, Chong K, Viero S, Thompson M, Blaser S. Prenatal diagnosis of solitary median maxillary central incisor syndrome by magnetic resonance imaging. Ultrasound Obstet Gynecol 2008; 32:120-122. [PMID: 18570243 DOI: 10.1002/uog.5388] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Affiliation(s)
- N Johnson
- Division of Maternal-Fetal Medicine, Mount Sinai Hospital, Toronto, Ontario, Canada.
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Wang H, Liu Y, Chong K, Liu BY, Ye HC, Li ZQ, Yan F, Li GF. Earlier flowering induced by over-expression of CO gene does not accompany increase of artemisinin biosynthesis in Artemisia annua. Plant Biol (Stuttg) 2007; 9:442-6. [PMID: 17099845 DOI: 10.1055/s-2006-924634] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
The early flowering gene CONSTANS (CO) from Arabidopsis thaliana was transferred into Artemisia annua using the Agrobacterium tumefaciens-mediated transformation system. The plant expression vector pBI CO was constructed by inserting the CO gene into the binary vector pBI121 under the control of CaMV 35S promoter. Analyses of PCR, PCR Southern blot, and Southern blot revealed that the transgenic plants contained the foreign CO gene. The results of RT-PCT and RT-PCR Southern blot suggested that the foreign CO gene had expressed at the transcriptional level. Although the flowering time of the CO transgenic plant was about 2 weeks earlier than that of the non-transgenic plant under short-day conditions, no significant difference in artemisinin content was found between the flowering transgenic plant and the non-flowering non-transgenic plant. These results show that the usually observed increase of artemisinin content before plant flowering under natural conditions is not a direct consequence of flowering itself, perhaps there is even no direct linkage between flowering and artemisinin biosynthesis.
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Affiliation(s)
- H Wang
- Key Laboratory of Phytosynthesis and Environmental Molecular Physiology, Institute of Botany, The Chinese Academy of Sciences, Nanxincun 20#, Xiangshan, Haidian District, Beijing 100093, China
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Ben-Neriah Z, Withers S, Thomas M, Toi A, Chong K, Pai A, Velscher L, Vero S, Keating S, Taylor G, Chitayat D. OEIS complex: prenatal ultrasound and autopsy findings. Ultrasound Obstet Gynecol 2007; 29:170-7. [PMID: 17221944 DOI: 10.1002/uog.3874] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
OBJECTIVE To describe prenatal ultrasound and autopsy findings in fetuses with OEIS (omphalocele, bladder exstrophy, imperforate anus, spina bifida) complex. METHODS This was a retrospective study of the nine cases with OEIS complex diagnosed at our center using detailed fetal ultrasound during the last 10 years. We summarized the fetal ultrasound findings that led to the diagnosis and compared them with the autopsy results. RESULTS All affected fetuses were diagnosed using detailed fetal ultrasound after 16 weeks' gestation. The main prenatal findings were omphalocele, skin-covered lumbosacral neural tube defect, non-visualized bladder and limb defects. Prenatal sonography failed to detect the abnormal genitalia, bladder exstrophy and anal atresia. All cases had abnormalities in a 'diaper distribution', which helped in making the prenatal diagnosis. Eight of the nine couples chose to terminate the pregnancies following multidisciplinary counseling. The pregnancy that was continued was a case with dizygotic twins discordant for OEIS, and the affected fetus died in utero. CONCLUSIONS The combination of the following ultrasound findings: ventral wall defect, spinal defect and a non-visualized bladder with or without limb defects, are characteristic of OEIS complex. Diagnosis can be made with confidence as early as 16 weeks' gestation, although earlier diagnosis may be possible.
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Affiliation(s)
- Z Ben-Neriah
- The Department of Human Genetics, Hadassah Medical Center, The Hebrew University, Jerusalem, Israel
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Wilson JN, Kinsler V, Mallone M, Chong K, Thompson D, Vorster J, Atherton D. Oral 1 Congenital neurocristic hamartoma presenting as tumour within the central nervous system. Br J Dermatol 2006. [DOI: 10.1111/j.1365-2133.2006.7385_1.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Kobrin B, Zhang T, Grimes MT, Chong K, Wanebo M, Chinn J, Nowak R. An Improved Chemical Resistance and Mechanical Durability of Hydrophobic FDTS Coatings. ACTA ACUST UNITED AC 2006. [DOI: 10.1088/1742-6596/34/1/074] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Zhuang X, Xu Y, Chong K, Lan L, Xue Y, Xu Z. OsAGAP, an ARF-GAP from rice, regulates root development mediated by auxin in Arabidopsis. Plant Cell Environ 2005; 28:147-56. [PMID: 16010732 DOI: 10.1111/j.1365-3040.2004.01253.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Arf (ADP-ribosylation factor) proteins, which mediate vesicular transport, have little or no intrinsic GTPase activity. They rely on the action of GTPase-activating proteins (GAPs) and guanine nucleotide exchange factors (GEFs) for their function. In the present study the OsAGAP gene in rice, which encoded a protein with predicted structure similar to ArfGAP, was identified. The purified OsAGAP-GST fusion protein was able to stimulate the GTPase activity of rice Arf. Furthermore, OsAGAP can rescue the defect of vesicular transport in the yeast gcs1 delta glo3 delta double-mutant cells. Transgenic Arabidopsis with OsAGAP constitutively expression showed reduced apical dominance, shorter primary roots, increasing number of longer adventitious roots. Many of the phenotypes can be phenocopied by treatment of exogenous indoleacetic acid level (IAA) in wild-type plants. Determination of whole-plant IAA level showed that there is a sharp increase of free IAA in OsAGAP transgenic Arabidopsis seedlings. In addition, removal of the 4-day-old shoot apex could inhibit the adventitious root formation in the transgenic seedlings. These results suggest OsAGAP, an ARF-GAP of rice, maybe involved in the mediation of plant root development by regulating auxin level.
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Affiliation(s)
- X Zhuang
- Key Laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany, CAS, Beijing, China
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Mitchell J, Punthakee Z, Lo B, Bernard C, Chong K, Newman C, Cartier L, Desilets V, Cutz E, Hansen IL, Riley P, Polychronakos C. Neonatal diabetes, with hypoplastic pancreas, intestinal atresia and gall bladder hypoplasia: search for the aetiology of a new autosomal recessive syndrome. Diabetologia 2004; 47:2160-7. [PMID: 15592663 DOI: 10.1007/s00125-004-1576-3] [Citation(s) in RCA: 73] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2004] [Accepted: 07/31/2004] [Indexed: 10/26/2022]
Abstract
AIMS/HYPOTHESIS Neonatal diabetes is a rare disease with several identified molecular aetiologies. Despite associations with other malformations, neonatal diabetes with intestinal and biliary anomalies has not been described. The current study aims to describe a new syndrome, and to examine a possible link with one of three genes known to cause neonatal diabetes. METHODS Five clinical cases are described. Immunohistochemical staining for pancreatic islet hormones was performed on three of the infants. DNA from one infant was analysed for abnormalities of the PLAGL-1 (ZAC), glucokinase and PDX-1 (IPF-1) genes. RESULTS Five infants (two sibling pairs from two families, and an isolated case) presented with neonatal diabetes, hypoplastic or annular pancreas, jejunal atresia, duodenal atresia and gall bladder aplasia or hypoaplasia. One sibling pair was born to consanguineous parents. One patient with a milder form is surviving free of insulin. Four children died in the first year of life despite aggressive medical management. Pancreatic immunohistochemistry revealed few scattered chromogranin-A-positive cell clusters but complete absence of insulin, glucagon and somatostatin. Exocrine histology was variable. In one case from the consanguineous family, molecular analysis showed no duplication or uniparental isodisomy of PLAGL-1 at 6q24, no contiguous gene deletion involving the glucokinase gene, and no mutation in the coding sequences or splice sites of PDX-1. CONCLUSIONS/INTERPRETATION This combination of multiple congenital abnormalities has not been previously described and probably represents a new autosomal recessive syndrome involving a genetic abnormality that interferes with normal islet development and whose aetiology is as yet unknown.
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Affiliation(s)
- J Mitchell
- Division of Endocrinology and Metabolism, Montreal Children's Hospital, McGill University, Montreal, Quebec, Canada
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Jia SQ, Yong WD, Xu WZ, Xu YY, Wu JS, Chong K, Tan KH, Xu ZH. Existence of homologous sequences corresponding to cDNA of the ver gene in diverse higher plant species. Cell Res 2001; 11:265-71. [PMID: 11787771 DOI: 10.1038/sj.cr.7290095] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [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: 11/09/2022] Open
Abstract
The presence of DNA homologues corresponding to verc203 (vernalization-related cDNA clone) was investigated by molecular hybridization techniques. The genes were detected in 16 plant species that cover 12 subclasses of the Takhtajan system of angiosperms classification including diverse model species. The results of Southern blot analysis showed a low copy number of this gene existed in rice, wheat, barley and Arabidopsis. The hybridization result of PCR products demonstrated the conservation of the gene corresponding to ver203 in diverse plants. The phylogenetic tree of the ver203 gene in tested plants was supported by evolution relationship of species. The ver203 gene expressed in a vernalized plumule winter wheat, instead of the root. And the endosperm before the treatment was essential for the ver203 expression during vernalization in wheat. In Arabidopsis thaliana, the pattern of expression showed that the gene corresponding to ver203 was expressed at low temperature for 14 days. Gibberellin (GA3) may accelerate the expression of ver203 gene in Arabidopsis exposed to low temperature. However, it could not replace vernalization treatment to initiate the gene expression.
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Affiliation(s)
- S Q Jia
- Research Center for Molecular and Developmental Biology, Institute of Botany, Chinese Academy of Sciences, Beijing
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Liang T, Tan K, Chong K, Zhu Z, Pongor S, Simoncsits A. Selection and design of high affinity DNA ligands for mutant single-chain derivatives of the bacteriophage 434 repressor. Sci China C Life Sci 2001; 44:274-286. [PMID: 18726407 DOI: 10.1007/bf02879334] [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] [Subscribe] [Scholar Register] [Received: 11/14/2000] [Indexed: 05/26/2023]
Abstract
Single-chain repressor RR(Tres) is a derivative of bacteriophage 434 repressor, which contains covalently dimerized DNA-binding domains (amino acids 1-69) of the phage 434 repressor. In this single-chain molecule, the wild type domain R is connected to the mutant domain R(TRES) by a recombinant linker in a head-to-tail arrangement. The DNA-contacting amino acids of R(TRES) at the -1, 1, 2, and 5 positions of the a3 helix are T, R, E, S respectively. By using a randomized DNA pool containing the central sequence -CATACAAGAAAGNNNNNNTTT-, a cyclic,in vitro DNA-binding site selection was performed. The selected population was cloned and the individual members were characterized by determining their binding affinities to RR(Tres) The results showed that the optimal operators contained the TTAC or TTCC sequences in the underlined positions as above, and that the Kd values were in the 1 x 10(-12) mol/L-1 x 10(11) mol/L concentration range. Since the affinity of the natural 434 repressor to its natural operator sites is in the 1 x 10(-9) mol/L range, the observed binding affinity increase is remarkable. It was also found that binding affinity was strongly affected by the flanking bases of the optimal tetramer binding sites, especially by the base at the 5' position. We constructed a new homodimeric single-chain repressor R(TRES)R(TRES) and its DNA-binding specificity was tested by using a series of new operators designed according to the recognition properties previously determined for the R(TREs) domain. These operators containing the consensus sequenceGTAAGAAARNTTACN orGGAAGAAARNTTCCN (R is A or G) were recognized by R(TRES)R(TRES) specifically, and with high binding affinity. Thus, by using a combination of random selection and rational design principles, we have discovered novel, high affinity protein-DNA interactions with new specificity. This method can potentially be used to obtain new binding specificity for other DNA-binding proteins.
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Affiliation(s)
- T Liang
- Institute of Botany, Chinese Academy of Sciences, 100093, Beijing, China
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Luo GX, Victor K, Chong K, McNeeley P, Ramirez D, Preclaro J, Linnik MD, Campbell MA. Identification of a peptide that protects the human acetylcholine receptor against antigenic modulation. J Immunol Methods 2001; 251:177-86. [PMID: 11292492 DOI: 10.1016/s0022-1759(01)00296-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [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: 11/30/2022]
Abstract
mAb 192 is a rat monoclonal antibody with very high affinity for the major immunogenic region (MIR) of the human muscle acetylcholine receptor (AChR). An epitope mimic of this antibody was selected from a phage display peptide library screened with mAb 192. The peptide-presenting phage has been shown to specifically bind to solid phase mAb 192 with an equilibrium dissociation constant (K(d)) of 8.45x10(-9) M, as directly measured with surface plasmon resonance. This value represents the avidity of the interaction between selected phage and mAb 192. A synthetic version of this peptide QPSPYNGWRMEI, referred to as MG15, binds to its selecting antibody and blocks the interaction of mAb 192 with human AChR. Peptide MG15 was able to protect acetylcholine receptors on human RD cells from antibody-mediated down-modulation. The negative charge of glutamic acid plays a important role in antibody binding. Replacement of the glutamic acid with an alanine completely abolishes the inhibitory activity.
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Affiliation(s)
- G X Luo
- La Jolla Pharmaceutical Company, 6455 Nancy Ridge Drive, San Diego, CA 92121, USA
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Chong K, Wang WX. Comparative studies on the biokinetics of Cd, Cr, and Zn in the green mussel Perna viridis and the Manila clam Ruditapes philippinarum. Environ Pollut 2001; 115:107-121. [PMID: 11586766 DOI: 10.1016/s0269-7491(01)00087-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A kinetic approach was employed to determine the rates of metal uptake (Cd, Cr and Zn) from the dissolved phase and the rate constants of metal depuration in the mussel Perna viridis and the clam Ruditapes philippinarum. The effects of ambient metal concentration, salinity, and body size on the metal influx rate were examined. A linear positive relationship was observed between the metal influx rate and the metal concentration in ambient seawater. There was some evidence that Zn uptake was regulated by the bivalves in response to an increase in ambient Zn concentration. The uptake rate constant was highest for Zn and lowest for Cr in both bivalves, and was higher in mussels than in clams. The metal influx rate decreased by 1.6-1.8 times for the three metals when the salinity was increased from 15 ppt to 30 ppt. However, the effect of salinity on Zn influx in mussels was not statistically significant. A negative relationship of Cd and Zn influx rates with tissue dry weight was also found in both bivalves. Cr uptake in mussels was not significantly correlated with body size, but its uptake in clams was significantly correlated with body size. Metal concentration in ambient seawater appeared to be the most determining factor on metal uptake from the dissolved phase in both bivalves. The efflux rate constants of the three metals were within the range of 0.01-0.03 d-1, and were comparable between the mussels and the clams. Using a simple bioenergetic-based kinetic model, it was shown that both dissolved uptake and food ingestion can contribute to metal accumulation in the bivalves. However, Zn accumulation in the clam R. philippinarum was dominated by uptake from food ingestion. Metal partitioning in ingested food was found to be critical in affecting the relative importance of metal uptake from the dissolved phase and food source, primarily because of the large variability of this parameter in natural environments.
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Affiliation(s)
- K Chong
- Department of Biology, Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon, Hong Kong
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Chong K, Wang W. Bioavailability of sediment-bound Cd, Cr and Zn to the green mussel Perna viridis and the Manila clam Ruditapes philippinarum. J Exp Mar Biol Ecol 2000; 255:75-92. [PMID: 11090853 DOI: 10.1016/s0022-0981(00)00296-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We assessed the degree to which Cd, Cr and Zn bound with sediment were assimilated by the green mussel Perna viridis and the Manila clam Ruditapes philippinarum. The influences of the metal concentration in the sediment, the presence of phytoplankton, and the oxidation condition of the sediment on metal assimilation were examined. No major difference was found for metal assimilation efficiency (AE) in sediment with different metal concentrations, except for Cd in the green mussels, in which the AE increased by 1.7x when the Cd concentration in sediment was elevated to 15x the natural background level. The higher assimilation of Cd with increasing Cd load in ingested sediment may be due to the higher desorption of Cd in the acidic gut of the bivalves. Both mussels and clams assimilated metals at a higher efficiency from the diatom diet (Thalassiosira pseudonana) than from inorganic sediment particles. The presence of algal particles had little influence on metal assimilation from ingested sediment, and conversely, the presence of sedimentary particles had little effect on metal assimilation from ingested diatom (except for Cd in the mussels). In the mussels, AEs were higher from oxic sediment than from anoxic sediment by 3.1x for Cd, 2.0x for Cr, and 1.4x for Zn, and in the clams AEs were higher from oxic sediment by 2.8x for Cd, 2.0x for Cr, and 2.0x for Zn. Our study suggested that metals associated with anoxic sediment can be potentially available to marine bivalves, and that metal AEs determined for a single diet were probably not affected by the presence of other food particles.
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Affiliation(s)
- K Chong
- Department of Biology, The Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon, Hong Kong
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Affiliation(s)
- J. L. Rose
- Department of Chemical and Petroleum Engineering, University of Calgary, 2500 University Drive N.W., Calgary, Alberta T2N 1N4, Canada
| | - W. Y. Svrcek
- Department of Chemical and Petroleum Engineering, University of Calgary, 2500 University Drive N.W., Calgary, Alberta T2N 1N4, Canada
| | - W. D. Monnery
- Department of Chemical and Petroleum Engineering, University of Calgary, 2500 University Drive N.W., Calgary, Alberta T2N 1N4, Canada
| | - K. Chong
- Core Laboratories Canada Ltd., 2810 12th Street N.E., Calgary, Alberta T2E 7P7, Canada
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Chai J, Takahashi Y, Sulaiman F, Chong K, Lautenschlager EP. Probability of fracture of all-ceramic crowns. INT J PROSTHODONT 2000; 13:420-4. [PMID: 11203665] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
PURPOSE The study compared the probability of fracture of 4 systems of all-ceramic crowns fabricated on maxillary central incisors. MATERIALS AND METHODS The 4 all-ceramic crown systems were: (1) a glass-infiltrated, sintered alumina system (In-Ceram) fabricated conventionally, (2) the same system with machine-milled alumina cores (CEREC 2), (3) a heat-press, leucite-reinforced glass-ceramic system (IPS Empress), and (4) a high-purity, high-density alumina system (Procera). Ten crowns of each system were fabricated and compressed at 45 degrees at the palatal surface until failure. The data were analyzed with the Weibull method. RESULTS There were no significant differences in the probability of fracture among the 4 systems studied. CONCLUSION The likelihood of fracture of these crown systems on central incisors should be similar.
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Affiliation(s)
- J Chai
- Northwestern University Dental School, 240 East Huron Street, Chicago, Illinois 60611, USA.
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Hodgkins PR, Kriss A, Boyd S, Chong K, Thompson D, Taylor DS, Russell-Eggitt I, Harris CM. A study of EEG, electroretinogram, visual evoked potential, and eye movements in classical lissencephaly. Dev Med Child Neurol 2000; 42:48-52. [PMID: 10665975 DOI: 10.1017/s0012162200000098] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
EEG, flash electroretinogram (ERG), and visual evoked potential (VEP) findings are described in eight children with classical lissencephaly (six girls, two boys), with a mean age of 17.6 months (range 2 to 60 months). The EEG shows typically high-voltage activity. Eye movements were formally recorded in two patients, and both showed features associated with oculomotor apraxia. The ERG and VEP to flash stimulation were normal in all cases. Two subjects had pattern reversal stimulation, and their pattern VEPs were within normal limits. Some patients with lissencephaly may appear to have delayed visual maturation on first presentation, and EEG and eye movement studies are valuable in indicating neurological deficiency at an early stage in these subjects.
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Affiliation(s)
- P R Hodgkins
- Department of Ophthalmology, Great Ormond Street Hospital for Children, London, UK
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Thompson DA, Kriss A, Chong K, Harris C, Russell-Eggitt I, Shawkat F, Neville BG, Aclimandos W, Taylor DS. Visual-evoked potential evidence of chiasmal hypoplasia. Ophthalmology 1999; 106:2354-61. [PMID: 10599670 DOI: 10.1016/s0161-6420(99)90539-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [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: 10/27/2022] Open
Abstract
PURPOSE To show that chiasmal hypoplasia or aplasia need not be an isolated developmental anomaly and to examine the spectrum of associated clinical findings to explore the possibility that these patients may represent a phenotypic manifestation of a developmental gene anomaly. DESIGN An observational case series. PARTICIPANTS Five infants, between several weeks and 7 months of age, in whom the electrophysiologic characteristic of chiasmal hypoplasia had been noted were included. METHODS Flash electroretinography and flash and pattern visual-evoked potentials (VEPs) were elicited from all patients. Clinical ophthalmologic examinations, including funduscopy, were performed, and all patients had magnetic resonance imaging (MRI) brain scans. MAIN OUTCOME MEASURES The occipital distribution of monocular VEP response peaks was studied. The symmetry of lateral channel responses was compared for monocular stimulation. RESULTS All five patients had a crossed asymmetry in the monocular VEP occipital distribution, which is consistent with a paucity of fibers crossing at the chiasm. The MRI findings supported this electrophysiologic observation, illustrating degrees of chiasmal hypoplasia and variable coincidence of other midline abnormalities of the brain. Optic disc appearances varied from normal to hypoplastic and colobomatous. CONCLUSIONS The ophthalmologic and MRI findings of five patients who showed a crossed asymmetry in monocular flash VEPs are consistent with a paucity of axons crossing at the chiasm. The similarities between achiasmia in humans and mice due to a Pax2 gene anomaly are discussed.
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Affiliation(s)
- D A Thompson
- Ophthalmology Department, Great Ormond Street Hospital NHS Trust, London, England.
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Herskhovitz E, Young E, Rainer J, Hall CM, Lidchi V, Chong K, Vellodi A. Bone marrow transplantation for Maroteaux-Lamy syndrome (MPS VI): long-term follow-up. J Inherit Metab Dis 1999; 22:50-62. [PMID: 10070618 DOI: 10.1023/a:1005447232027] [Citation(s) in RCA: 110] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We describe the results of bone marrow transplantation (BMT) in four patients with mucopolysaccharidosis type VI (MPS VI, McKusick 253200)--Maroteaux-Lamy disease. The indications for transplantation were cardiomyopathy in three patients and severe obstructive sleep apnoea in one. The follow-up period ranges between 1 and 9 years, and three of the patients are at mainstream schools. In all of the patients the facial features have become less coarse and the cardiac manifestations have improved or remained stable. However, skeletal changes have persisted or even progressed, although posture and joint mobility have improved and all the patients have remained ambulatory and active. BMT appears to prolong survival and improve the quality of life in MPS VI patients, but careful selection of patients is essential.
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Affiliation(s)
- E Herskhovitz
- Metabolic Unit, Great Ormond Street Hospital for Children NHS Trust, London, UK
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Affiliation(s)
- J J Weber
- Department of Pharmacy Services, Hermann Hospital (HH), Houston, TX 77030-1501, USA.
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Karavodin LM, Robbins J, Chong K, Hsu D, Ibanez C, Mento S, Jolly D, Fong TC. Generation of a systemic antitumor response with regional intratumoral injections of interferon gamma retroviral vector. Hum Gene Ther 1998; 9:2231-41. [PMID: 9794207 DOI: 10.1089/hum.1998.9.15-2231] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [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: 11/13/2022] Open
Abstract
The generation of a lasting systemic immune response is a primary goal for cancer immunotherapy. Here we examine the ability of high-titer IFN-gamma retroviral vector injected into an accessible tumor to generate significant antitumor responses at a distal untreated site. CT26 or B16F10 murine tumors were inoculated subcutaneously to form solid tumors in BALB/c or C57BL/6 mice. Seven to 10 days postinoculation, high-titer IFN-gamma retroviral vector was directly injected into the subcutaneous tumor nodule, and optimal dose and course of therapy were determined. As a model for disseminated disease, mice were inoculated intravenously with CT26 cells to form pulmonary lesions, at the same time as the subcutaneous injections. Regression of subcutaneous tumor correlated with a systemic response at the distal lung metastases in the IFN-gamma-treated group (p < 0.0005). Splenocytes from mice with completely regressed tumors had a twofold increase in percent specific cytotoxicity in a standard CTL assay as compared with nonresponding mice. CD8+ T cells were shown to be essential for the regional and systemic antitumor response, as determined by in vivo cell depletion experiments. These data demonstrate that IFN-gamma retroviral vector gene therapy delivered intralesionally can generate significant inhibition of pulmonary tumor formation distal to the treatment site. The data from these preclinical studies suggest the potential clinical value of retroviral vector-mediated cytokine gene therapy for systemic cancer.
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Abstract
Epileptic nystagmus (EN) is a rare form of nystagmus that occurs only during epileptic seizures. We report an infantile case in which EN was first noted at 10 days of age. Electronystagmography showed a right-beating nystagmus with predominantly linear slow phases that traversed the midline. Neuro-imaging revealed dysplasia of the left middle temporal gyrus extending posteriorly into the parieto-occipital cortex. The right hemisphere and subcortical structures appeared normal. Perfusion studies demonstrated interictal hypoperfusion with ictal hyperperfusion in the left temporal lobe. Electrocorticography demonstrated spiking over the left temporal-parieto-occipital region. Following extensive surgical resection of this area and weaning of anti-convulsants, the child has remained seizure-free without nystagmus. This case demonstrates the cortical origin of EN, and shows that infant cortex has functioning efferent connections to brainstem oculomotor centres from 10 days of age.
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Affiliation(s)
- C M Harris
- Great Ormond Street Hospital for Children, NHS Trust and Institute of Child Health, University College London, UK
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Angata K, Nakayama J, Fredette B, Chong K, Ranscht B, Fukuda M. Human STX polysialyltransferase forms the embryonic form of the neural cell adhesion molecule. Tissue-specific expression, neurite outgrowth, and chromosomal localization in comparison with another polysialyltransferase, PST. J Biol Chem 1997; 272:7182-90. [PMID: 9054414 DOI: 10.1074/jbc.272.11.7182] [Citation(s) in RCA: 117] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
PST and STX are polysialyltransferases that form polysialic acid in the neural cell adhesion molecule (N-CAM), although it is not known why these two polysialyltransferases exist. In the present study, we have first isolated cDNA encoding human STX, which includes 5'-untranslated sequence. Northern blot analysis, using this cDNA and PST cDNA previously isolated by us, demonstrated that PST and STX are expressed in different fetal and adult tissues. STX is primarily expressed in embryonic tissues, but only modestly in adult heart, brain, and thymus. PST, on the other hand, is continuously expressed in adult heart, brain, thymus, spleen, small and large intestines, and peripheral blood leukocytes. In various parts of adult brain, the relative amount of PST and STX appears to be substantially different depending on the regions. The analysis by in situ hybridization of mouse adult brain, however, suggests that polysialic acid in the hippocampal formation is synthesized by both STX and PST. HeLa cells doubly transfected with the isolated STX cDNA and N-CAM cDNA supported neurite outgrowth much better than HeLa cells expressing N-CAM alone. However, polysialic acid synthesized by PST appears to be a better substratum than that synthesized by STX. Moreover, the genes for PST and STX were found to reside at chromosome 5, band p21 and chromosome 15, band q26, respectively. These results, taken together, strongly suggest that PST and STX are expressed distinctly in tissue-specific and cell-specific manners and that they apparently have distinct roles in development and organogenesis.
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Affiliation(s)
- K Angata
- Glycobiology and Neurobiology Programs, La Jolla Cancer Research Center, The Burnham Institute, La Jolla, California 92037, USA
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Leitch RJ, Thompson D, Harris CM, Chong K, Russell-Eggitt I, Kriss A. Achiasmia in a case of midline craniofacial cleft with seesaw nystagmus. Br J Ophthalmol 1996; 80:1023-4. [PMID: 8976735 PMCID: PMC505685 DOI: 10.1136/bjo.80.11.1023-a] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Chong K, Loughlin T, Moeder C, Perpall HJ, Thompson R, Grinberg N, Smith GB, Bhupathy M, Bicker G. Drug substance manufacture process control: application of flow injection analysis and HPLC for monitoring an enantiospecific synthesis. J Pharm Biomed Anal 1996; 15:111-21. [PMID: 8895082 DOI: 10.1016/0731-7085(96)01810-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [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: 02/02/2023]
Abstract
Effective process control can only be achieved through an understanding of the operating issues of the reaction. The development and use of effective and rugged analytical methods is necessary to monitor these parameters. The intent of this paper is to present some key analytical issues encountered in the synthesis of MK-0679, an LTD4 antagonist. In a key step of the compound's synthesis, a prochiral diester intermediate undergoes an enantioselective enzymatic hydrolysis (in the presence of Triton X-100) leading to the (S)-ester acid. Subsequent processing transforms the ester acid into the final product. The residual amount of the detergent in the final product, the rapid determination of the enzymatic activity and the optical purity of the final product emerged as key issues in the control of the reaction. As a solution, two techniques were utilized and are presented: flow injection analysis and HPLC.
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Affiliation(s)
- K Chong
- Merck Research Laboratories, Rahway, NJ 07065-0900, USA
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Howard B, Burrascano M, McCallister T, Chong K, Gangavalli R, Severinsson L, Jolly DJ, Darrow T, Vervaert C, Abdel-Wahab Z. Retrovirus-mediated gene transfer of the human gamma-IFN gene: a therapy for cancer. Ann N Y Acad Sci 1994; 716:167-87. [PMID: 8024193 DOI: 10.1111/j.1749-6632.1994.tb21711.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [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: 01/28/2023]
Abstract
A retroviral vector-mediated gene transfer system was used to introduce m gamma-IFN and h gamma-IFN genes into mouse and human tumor cells, respectively. Murine tumor cell lines and primary human melanoma tumor cells were successfully transduced with gamma-IFN vector, and these transduced cells secreted measurable levels of biologically active m gamma-IFN and h gamma-IFN, respectively. Both murine and human tumor cell lines that expressed gamma-IFN exhibited increased surface expression of HLA class I antigens when tested by Western blot and FACS analysis. gamma-IFN--transduced human melanoma cells were more active in stimulating tumor-specific cytolytic activity of CTLs from melanoma patients in vitro. m gamma-IFN--transduced tumor cells were substantially less tumorigenic than the corresponding parent tumor cell lines in immune-competent mice. In addition, injection of m gamma-IFN--transduced tumor cells resulted in activation of tumor-specific CTL in vivo. We plan to use gamma-IFN--transduced autologous tumor cells to boost host immune responses as a potential therapy for human melanoma.
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Affiliation(s)
- B Howard
- Viagene, Inc., San Diego, California 92121
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Meurs EF, Watanabe Y, Kadereit S, Barber GN, Katze MG, Chong K, Williams BR, Hovanessian AG. Constitutive expression of human double-stranded RNA-activated p68 kinase in murine cells mediates phosphorylation of eukaryotic initiation factor 2 and partial resistance to encephalomyocarditis virus growth. J Virol 1992; 66:5805-14. [PMID: 1382142 PMCID: PMC241456 DOI: 10.1128/jvi.66.10.5805-5814.1992] [Citation(s) in RCA: 201] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The cDNA encoding interferon-induced human double-stranded RNA-activated p68 kinase was expressed in murine NIH 3T3 cells by using the pcDNA1/neo vector. Several stable clones were selected which expressed either the wild-type kinase or an inactive mutant possessing a single amino acid substitution in the invariant lysine 296 in the catalytic domain II. The transfected wild-type kinase showed properties similar to those of the natural kinase, such as subcellular ribosomal localization and dependence on double-stranded RNA for autophosphorylation. Upon infection with encephalomyocarditis virus (EMCV), wild-type- but not mutant-expressing clones were found to partially resist virus growth. Such natural antiviral activity was virus specific, since no inhibition was observed in the case of vesicular stomatitis virus infection. In accord with EMCV inhibition, the wild-type p68 kinase was found to be highly phosphorylated during infection. Furthermore, its natural substrate, the small subunit of protein synthesis initiation factor eIF2, was phosphorylated. These results demonstrate that p68 kinase is activated during EMCV infection, leading to reduced virus production.
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Affiliation(s)
- E F Meurs
- Unit of Virology and of Cellular Immunology (UA CNRS 1157), Institut Pasteur, Paris, France
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Feng GS, Chong K, Kumar A, Williams BR. Identification of double-stranded RNA-binding domains in the interferon-induced double-stranded RNA-activated p68 kinase. Proc Natl Acad Sci U S A 1992; 89:5447-51. [PMID: 1351683 PMCID: PMC49309 DOI: 10.1073/pnas.89.12.5447] [Citation(s) in RCA: 142] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The double-stranded RNA (dsRNA)-binding domain of the human p68 kinase has been localized to the N-terminal half of the enzyme by using progressive deletion analysis and in vitro binding assays. To further define the domains responsible for binding to dsRNA, we cloned the mouse dsRNA-activated p65 kinase and used sequence alignment to identify conserved domains in the N-terminal region. Deletions in either of two 12-amino-acid-long and arginine- or lysine-rich regions abrogated binding to dsRNA. Moreover, in an in vivo growth inhibition assay in the yeast Saccharomyces cerevisiae, these mutants failed to exhibit a slow-growth phenotype.
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Affiliation(s)
- G S Feng
- Research Institute, Hospital for Sick Children, Toronto, Canada
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