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DeVries S, Kron P, Husband BC. Gamete sex and elevation affect genetically based variation for unreduced gamete production in a mixed-ploidy plant. Am J Bot 2024; 111:e16262. [PMID: 38031672 DOI: 10.1002/ajb2.16262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 10/26/2023] [Accepted: 10/27/2023] [Indexed: 12/01/2023]
Abstract
PREMISE Unreduced gametes are the primary mechanism of neopolyploid formation. Their production in diploid populations is arguably maladaptive, but the magnitude and patterns of genetically based variation maintained in natural populations are poorly understood. METHODS We examined variation in male and female unreduced gamete production among plants from different elevations in fireweed, Chamerion angustifolium, grown in a common environment. Using seeds from three high-elevation and three low-elevation diploid populations in one study, and a single diploid population in another, we estimated realized rates of unreduced male (sperm) and female (egg) gamete production by reciprocally pollinating diploid and tetraploid plants and estimating the incidence of tetraploid seeds using flow cytometry. RESULTS Unreduced gamete frequencies per plant were similar in the two studies (0.12% vs. 0.08%). High-elevation populations had a greater percentage of fruit with seeds from unreduced gametes, but a lower percentage of seeds per fruit than low-elevation populations. Female unreduced gamete frequencies differed among elevations, but male frequencies did not, and the gamete sexes were not correlated at the plant level. CONCLUSIONS We conclude that genetically based variation for unreduced gametes is maintained within and among natural populations, despite their fitness disadvantages, suggesting that local selection may be ineffective at purging them under some conditions.
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Affiliation(s)
- Sarah DeVries
- Department of Integrative Biology, University of Guelph, 50 Stone Rd E., Guelph, Ontario, N1G 2W1, Canada
| | - Paul Kron
- Department of Integrative Biology, University of Guelph, 50 Stone Rd E., Guelph, Ontario, N1G 2W1, Canada
| | - Brian C Husband
- Department of Integrative Biology, University of Guelph, 50 Stone Rd E., Guelph, Ontario, N1G 2W1, Canada
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2
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Koutecký P, Smith T, Loureiro J, Kron P. Best practices for instrument settings and raw data analysis in plant flow cytometry. Cytometry A 2023; 103:953-966. [PMID: 37807676 DOI: 10.1002/cyto.a.24798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 05/26/2023] [Accepted: 09/12/2023] [Indexed: 10/10/2023]
Abstract
Flow cytometry (FCM) is now the most widely used method to determine ploidy levels and genome size of plants. To get reliable estimates and allow reproducibility of measurements, the methodology should be standardized and follow the best practices in the field. In this article, we discuss instrument calibration and quality control and various instrument and acquisition settings (parameters, flow rate, number of events, scales, use of discriminators, peak positions). These settings must be decided before measurements because they determine the amount and quality of the data and thus influence all downstream analyses. We describe the two main approaches to raw data analysis (gating and histogram modeling), and we discuss their advantages and disadvantages. Finally, we provide a summary of best practice recommendations for data acquisition and raw data analysis in plant FCM.
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Affiliation(s)
- Petr Koutecký
- Department of Botany, Faculty of Science, University of South Bohemia, České Budějovice, Czechia
| | - Tyler Smith
- Agriculture and Agri-Food Canada (AAFC), Ottawa, Ontario, Canada
| | - João Loureiro
- Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | - Paul Kron
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
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3
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Greaves E, Kron P, Husband BC. Demographic and reproductive impacts of hybridization unrelated to hybrid viability in a native plant. Am J Bot 2023; 110:e16208. [PMID: 37409880 DOI: 10.1002/ajb2.16208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 04/28/2023] [Accepted: 05/03/2023] [Indexed: 07/07/2023]
Abstract
PREMISE Introduced species can influence native congeners through production of hybrids and introgression, but impacts not involving viable hybrids, such as reduced conspecific offspring and increased asexual seed production, are rarely examined. Here we tested for these demographic and reproductive consequences of hybridization between introduced, domesticated apple (Malus domestica) and native crabapple (M. coronaria) in southern Canada. METHODS We applied four pollination treatments (open, M. coronaria, M. domestica, open + M. coronaria) to focal M. coronaria trees across multiple years and assessed the number and reproductive origins of resulting seeds (hybrid or conspecific endosperm and, for each, sexual or asexual embryo) using flow cytometry. RESULTS In open-pollinated fruit, 27% of seeds had hybrid endosperm; 52% of embryos were asexual. The number of conspecific embryos (sexual or asexual) per fruit did not decline significantly with increasing hybridization, indicating no seed discounting, but hand pollinations using only domestic apple or crabapple pollen reduced the number of conspecific embryos significantly. Hybridization was not associated with a change in percentage asexual embryos, overall, but there was an increase in asexual embryos in tetraploid seeds, the maternal and most common offspring ploidy. CONCLUSIONS We conclude that hybridization can influence native Malus in ways beyond the production of viable hybrids, with significant implications for population dynamics and genetic structure.
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Affiliation(s)
- Elaina Greaves
- Department of Integrative Biology, University of Guelph, 50 Stone Road E., Guelph, Ontario, N1G 2W1, Canada
| | - Paul Kron
- Department of Integrative Biology, University of Guelph, 50 Stone Road E., Guelph, Ontario, N1G 2W1, Canada
| | - Brian C Husband
- Department of Integrative Biology, University of Guelph, 50 Stone Road E., Guelph, Ontario, N1G 2W1, Canada
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4
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Balakrishnan A, Jah A, Lesurtel M, Andersson B, Gibbs P, Harper SJF, Huguet EL, Kosmoliaptsis V, Liau SS, Praseedom RK, Ramia JM, Branes A, Lendoire J, Maithel S, Serrablo A, Achalandabaso M, Adham M, Ahmet A, Al-Sarireh B, Albiol Quer M, Alconchel F, Alejandro R, Alsammani M, Alseidi A, Anand A, Anselmo A, Antonakis P, Arabadzhieva E, de Aretxabala X, Aroori S, Ashley S, Ausania F, Banerjee A, Barabino M, Bartlett A, Bartsch F, Belli A, Beristain-Hernandez J, Berrevoet F, Bhatti A, Bhojwani R, Bjornsson B, Blaz T, Byrne M, Calvo M, Castellanos J, Castro M, Cavallucci D, Chang D, Christodoulis G, Ciacio O, Clavien P, Coker A, Conde-Rodriguez M, D'Amico F, D'Hondt M, Daams F, Dasari B, De Beillis M, de Meijer V, Dede K, Deiro G, Delgado F, Desai G, Di Gioia A, Di Martino M, Dixon M, Dorovinis P, Dumitrascu T, Ebata T, Eilard M, Erdmann J, Erkan M, Famularo S, Felli E, Fergadi M, Fernandez G, Fox A, Galodha S, Galun D, Ganandha S, Garcia R, Gemenetzis G, Giannone F, Gil L, Giorgakis E, Giovinazzo F, Giuffrida M, Giuliani T, Giuliante F, Gkekas I, Goel M, Goh B, Gomes A, Gruenberger T, Guevara O, Gulla A, Gupta A, Gupta R, Hakeem A, Hamid H, Heinrich S, Helton S, Heumann A, Higuchi R, Hughes D, Inarejos B, Ivanecz A, Iwao Y, Iype S, Jaen I, Jie M, Jones R, Kacirek K, Kalayarasan R, Kaldarov A, Kaman L, Kanhere H, Kapoor V, Karanicolas P, Karayiannakis A, Kausar A, Khan Z, Kim DS, Klose J, Knowles B, Koh P, Kolodziejczyk P, Komorowski A, Koong J, Kozyrin I, Krishna A, Kron P, Kumar N, van Laarhoven S, Lakhey P, Lanari J, Laurenzi A, Leow V, Limbu Y, Liu YB, Lob S, Lolis E, Lopez-Lopez V, Lozano R, Lundgren L, Machairas M, Magouliotis D, Mahamid A, Malde D, Malek A, Malik H, Malleo G, Marino M, Mayo S, Mazzola M, Memeo R, Menon K, Menzulin R, Mohan R, Morgul H, Moris D, Mulita F, Muttillo E, Nahm C, Nandasena M, Nashidengo P, Nickkholgh A, Nikov A, Noel C, O'Reilly D, O'Rourke T, Ohtsuka M, Omoshoro-Jones J, Pandanaboyana S, Pararas N, Patel R, Patkar S, Peng J, Perfecto A, Perinel J, Perivoliotis K, Perra T, Phan M, Piccolo G, Porcu A, Primavesi F, Primrose J, Pueyo-Periz E, Radenkovic D, Rammohan A, Rowcroft A, Sakata J, Saladino E, Schena C, Scholer A, Schwarz C, Serrano P, Silva M, Soreide K, Sparrelid E, Stattner S, Sturesson C, Sugiura T, Sumo M, Sutcliffe R, Teh C, Teo J, Tepetes K, Thapa P, Thepbunchonchai A, Torres J, Torres O, Torzili G, Tovikkai C, Troncoso A, Tsoulfas G, Tuzuher A, Tzimas G, Umar G, Urbani L, Vanagas T, Varga, Velayutham V, Vigano L, Wakai T, Yang Z, Yip V, Zacharoulis D, Zakharov E, Zimmitti G. Heterogeneity of management practices surrounding operable gallbladder cancer - results of the OMEGA-S international HPB surgical survey. HPB (Oxford) 2022; 24:2006-2012. [PMID: 35922277 DOI: 10.1016/j.hpb.2022.06.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 06/22/2022] [Accepted: 06/28/2022] [Indexed: 12/12/2022]
Abstract
BACKGROUND Gallbladder cancer (GBC) is an aggressive, uncommon malignancy, with variation in operative approaches adopted across centres and few large-scale studies to guide practice. We aimed to identify the extent of heterogeneity in GBC internationally to better inform the need for future multicentre studies. METHODS A 34-question online survey was disseminated to members of the European-African Hepatopancreatobiliary Association (EAHPBA), American Hepatopancreatobiliary Association (AHPBA) and Asia-Pacific Hepatopancreatobiliary Association (A-PHPBA) regarding practices around diagnostic workup, operative approach, utilization of neoadjuvant and adjuvant therapies and surveillance strategies. RESULTS Two hundred and three surgeons responded from 51 countries. High liver resection volume units (>50 resections/year) organised HPB multidisciplinary team discussion of GBCs more commonly than those with low volumes (p < 0.0001). Management practices exhibited areas of heterogeneity, particularly around operative extent. Contrary to consensus guidelines, anatomical liver resections were favoured over non-anatomical resections for T3 tumours and above, lymphadenectomy extent was lower than recommended, and a minority of respondents still routinely excised the common bile duct or port sites. CONCLUSION Our findings suggest some similarities in the management of GBC internationally, but also specific areas of practice which differed from published guidelines. Transcontinental collaborative studies on GBC are necessary to establish evidence-based practice to minimise variation and optimise outcomes.
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Affiliation(s)
- Anita Balakrishnan
- Department of HPB Surgery, Cambridge University Hospitals NHS Foundation Trust, Hills Road, Cambridge, CB2 0QQ, United Kingdom.
| | - Asif Jah
- Department of HPB Surgery, Cambridge University Hospitals NHS Foundation Trust, Hills Road, Cambridge, CB2 0QQ, United Kingdom
| | - Mickael Lesurtel
- Department of HPB Surgery and Liver Transplantation, Beaujon Hospital, University of Paris Cité, 100 Bd du Général Leclerc, 92110, Clichy, France
| | - Bodil Andersson
- Department of Surgery, Lund University, Skane University Hospital, Lund, Sweden
| | - Paul Gibbs
- Department of HPB Surgery, Cambridge University Hospitals NHS Foundation Trust, Hills Road, Cambridge, CB2 0QQ, United Kingdom
| | - Simon J F Harper
- Department of HPB Surgery, Cambridge University Hospitals NHS Foundation Trust, Hills Road, Cambridge, CB2 0QQ, United Kingdom
| | - Emmanuel L Huguet
- Department of HPB Surgery, Cambridge University Hospitals NHS Foundation Trust, Hills Road, Cambridge, CB2 0QQ, United Kingdom
| | - Vasilis Kosmoliaptsis
- Department of HPB Surgery, Cambridge University Hospitals NHS Foundation Trust, Hills Road, Cambridge, CB2 0QQ, United Kingdom
| | - Siong S Liau
- Department of HPB Surgery, Cambridge University Hospitals NHS Foundation Trust, Hills Road, Cambridge, CB2 0QQ, United Kingdom
| | - Raaj K Praseedom
- Department of HPB Surgery, Cambridge University Hospitals NHS Foundation Trust, Hills Road, Cambridge, CB2 0QQ, United Kingdom
| | - Jose M Ramia
- Department of Surgery, Hospital General Universitario de Alicante, Avenida Pintor Baeza, 12 03010 Alicante, Spain
| | - Alejandro Branes
- Department of HPB Surgery, Hospital Sotero del Rio, Av. Concha y Toro 3459, Puente Alto, Región Metropolitana, Chile
| | - Javier Lendoire
- Department of Surgery, University of Buenos Aires, Hospital Dr Cosme Argerich, Buenos Aires, Argentina
| | - Shishir Maithel
- Department of Surgery, Emory University School of Medicine, Atlanta, GA, 30322 USA
| | - Alejandro Serrablo
- Department of HPB Surgery, Miguel Servet University Hospital, Zaragoza, Spain
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5
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Schneider M, Linecker M, Fritsch R, Mühlematter U, Stocker D, Pestalozzi B, Samaras P, Jetter A, Kron P, Petrowsky H, Nicolau C, Lehn JM, Humar B, Graf R, Clavien PA, Limani P. Phase Ib dose-escalation study of the hypoxia-modifier myo-inositol trispyrophosphate in patients with hepatopancreatobiliary tumors. Br J Surg 2022. [DOI: 10.1093/bjs/znac178.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
Objective
Hypoxia is present in most solid tumors and acts as a driver of malignancy. Myo-inositol trispyrophosphate (ITPP) is a novel re-oxygenating compound without apparent toxicity. In preclinical models, it potentiates the efficacy of subsequent chemotherapy through vascular normalization. We sought to assess the safety, tolerability, and preliminary efficacy of ITPP.
Methods
In this monocentric, open-label, dose-escalation study following a 3+3 design, eligible patients with advanced primary and secondary hepatopancreatobiliary tumors received nine 8-h infusions of ITPP during 3 weeks across eight dose levels (1866–14,500 mg/m2/dose), followed by standard chemotherapy. Primary endpoints were safety and tolerability. Secondary endpoints were pharmacokinetics and estimation of efficacy based on radiological responses and angiogenic serum markers. Registration number: NCT02528526.
Results
From April 2015 to July 2018, a total of 28 enrolled patients were assessed for the primary endpoints. ITPP was safe up to single doses of 12,390 mg/m2, and 32 ITPP-related adverse events occurred: 19 (67.8%) hypercalcemia, 5 (17.8%) hyponatremia, and 4 (14.2%) hypomagnesemia. Following ITPP monotherapy, 52% of patients displayed morphological disease stabilization. Following subsequent chemotherapy, 10% showed a partial response, and 60% had stable disease. Angiogenic markers were decreased in 60% after ITPP and tended to correlate with responses and survival after chemotherapy.
Conclusion
Administration of ITPP is safe up to 12,390 mg/m2 with favorable pharmacokinetics. Preliminary translational efficacy data show decreased angiogenic markers, which might indicate an anti-hypoxic effect and enhancement of chemotherapy through ITPP.
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Affiliation(s)
- M Schneider
- Department of Visceral Surgery, University Hospital Zurich , Zurich, Switzerland
| | - M Linecker
- Department of Visceral Surgery, University Hospital Zurich , Zurich, Switzerland
| | - R Fritsch
- Department of Oncology, University Hospital Zurich , Zurich, Switzerland
| | - U Mühlematter
- Department of Radiology, University Hospital of Zurich , Zurich, Switzerland
| | - D Stocker
- Department of Radiology, University Hospital of Zurich , Zurich, Switzerland
| | - B Pestalozzi
- Department of Oncology, University Hospital Zurich , Zurich, Switzerland
| | - P Samaras
- Oncology Center, Hirslanden Hospital Zurich , Zurich, Switzerland
| | - A Jetter
- Department of Pharmacology, University Hospital Zurich , Zurich, Switzerland
| | - P Kron
- Department of Visceral Surgery, University Hospital Zurich , Zurich, Switzerland
| | - H Petrowsky
- Department of Visceral Surgery, University Hospital Zurich , Zurich, Switzerland
| | - C Nicolau
- Friedman School of Nutrition Science and Policy, Tufts University , Boston, USA
| | - J-M Lehn
- Institute of Supramolecular Science and Engineering, University of Strasbourg , Strasbourg, France
| | - B Humar
- Department of Visceral Surgery, University Hospital Zurich , Zurich, Switzerland
| | - R Graf
- Department of Visceral Surgery, University Hospital Zurich , Zurich, Switzerland
| | - P-A Clavien
- Department of Visceral Surgery, University Hospital Zurich , Zurich, Switzerland
| | - P Limani
- Department of Visceral Surgery, University Hospital Zurich , Zurich, Switzerland
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6
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Engstrand J, Abreu de Carvalho LF, Aghayan D, Balakrishnan A, Belli A, Björnsson B, Dasari BVM, Detry O, Di Martino M, Edwin B, Erdmann J, Fristedt R, Fusai G, Gimenez-Maurel T, Hemmingsson O, Hidalgo Salinas C, Isaksson B, Ivanecz A, Izzo F, Knoefel WT, Kron P, Lehwald-Tywuschik N, Lesurtel M, Lodge JPA, Machairas N, Marino MV, Martin V, Paterson A, Rystedt J, Sandström P, Serrablo A, Siriwardena AK, Taflin H, van Gulik TM, Yaqub S, Özden I, Ramia JM, Sturesson C. Liver resection and ablation for squamous cell carcinoma liver metastases. BJS Open 2021; 5:6356812. [PMID: 34426830 PMCID: PMC8382975 DOI: 10.1093/bjsopen/zrab060] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 05/17/2021] [Indexed: 12/30/2022] Open
Abstract
Background Limited evidence exists to guide the management of patients with liver metastases from squamous cell carcinoma (SCC). The aim of this retrospective multicentre cohort study was to describe patterns of disease recurrence after liver resection/ablation for SCC liver metastases and factors associated with recurrence-free survival (RFS) and overall survival (OS). Method Members of the European–African Hepato-Pancreato-Biliary Association were invited to include all consecutive patients undergoing liver resection/ablation for SCC liver metastases between 2002 and 2019. Patient, tumour and perioperative characteristics were analysed with regard to RFS and OS. Results Among the 102 patients included from 24 European centres, 56 patients had anal cancer, and 46 patients had SCC from other origin. RFS in patients with anal cancer and non-anal cancer was 16 and 9 months, respectively (P = 0.134). A positive resection margin significantly influenced RFS for both anal cancer and non-anal cancer liver metastases (hazard ratio 6.82, 95 per cent c.i. 2.40 to 19.35, for the entire cohort). Median survival duration and 5-year OS rate among patients with anal cancer and non-anal cancer were 50 months and 45 per cent and 21 months and 25 per cent, respectively. For the entire cohort, only non-radical resection was associated with worse overall survival (hazard ratio 3.21, 95 per cent c.i. 1.24 to 8.30). Conclusion Liver resection/ablation of liver metastases from SCC can result in long-term survival. Survival was superior in treated patients with liver metastases from anal versus non-anal cancer. A negative resection margin is paramount for acceptable outcome.
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Affiliation(s)
- J Engstrand
- Division of Surgery, Department of Clinical Sciences, Karolinska Institutet at Danderyd Hospital, Stockholm, Sweden
| | - L F Abreu de Carvalho
- Department of Hepatopancreatobiliary Surgery and Liver Transplantation, Ghent University Hospital, Ghent, Belgium
| | - D Aghayan
- The Intervention Centre, Oslo University Hospital, Institute of Clinical Medicine, Medical Faculty, University of Oslo, Oslo, Norway.,Department of Surgery N1, Yerevan State Medical University after M. Heratsi, Yerevan, Armenia
| | - A Balakrishnan
- Department of Surgery, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | - A Belli
- Department of Abdominal Oncology, HPB Surgical Oncology Unit, National Cancer Institute, Fondazione G. Pascale-IRCCS, Naples, Italy
| | - B Björnsson
- Department of Surgery in Linköping, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - B V M Dasari
- Department of Hepatobiliary and Pancreatic Surgery, Queen Elizabeth Hospital, Birmingham, UK
| | - O Detry
- Department of Abdominal Surgery and Transplantation, CHU Liège, Liège, Belgium
| | - M Di Martino
- HPB Unit, Department of General and Digestive Surgery, Hospital Universitario La Princesa, Instituto de Investigación Sanitaria Princesa (IIS-IP), Universidad Autónoma de Madrid (UAM), Madrid, Spain
| | - B Edwin
- The Intervention Centre, Oslo University Hospital, Institute of Clinical Medicine, Medical Faculty, University of Oslo, Oslo, Norway
| | - J Erdmann
- Department of Surgery, Cancer Centre Amsterdam, Amsterdam UMC, University of Amsterdam, the Netherlands
| | - R Fristedt
- Department of Surgery, Skåne University Hospital, Lund University, Lund, Sweden
| | - G Fusai
- Department of HPB and Liver Transplant Surgery, Royal Free Hospital, NHS Foundation Trust, London, UK
| | - T Gimenez-Maurel
- Department of Surgery, Miguel Servet University Hospital, Zaragoza, Spain
| | - O Hemmingsson
- Department of Surgical and Perioperative Sciences, Umeå University, Umeå, Sweden
| | - C Hidalgo Salinas
- Department of HPB and Liver Transplant Surgery, Royal Free Hospital, NHS Foundation Trust, London, UK
| | - B Isaksson
- Department of Surgical Sciences, Uppsala University, Uppsala, Sweden
| | - A Ivanecz
- Department of Abdominal and General Surgery, University Medical Centre Maribor, Maribor, Slovenia
| | - F Izzo
- Department of Abdominal Oncology, HPB Surgical Oncology Unit, National Cancer Institute, Fondazione G. Pascale-IRCCS, Naples, Italy
| | - W T Knoefel
- Department of Surgery (A), Heinrich-Heine-University and University Hospital Düsseldorf, Düsseldorf, Germany
| | - P Kron
- Department of Hepatobiliary Surgery, Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - N Lehwald-Tywuschik
- Department of Surgery (A), Heinrich-Heine-University and University Hospital Düsseldorf, Düsseldorf, Germany
| | - M Lesurtel
- Department of Digestive Surgery and Liver Transplantation, Croix-Rousse University Hospital, Hospices Civils de Lyon, University of Lyon I, Lyon, France
| | - J P A Lodge
- Department of Hepatobiliary Surgery, Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - N Machairas
- 3rd Department of Surgery, National and Kapodistrian University of Athens, Attikon University Hospital, Athens, Greece
| | - M V Marino
- General Surgery Department, Azienda Ospedaliera Ospedali Riuniti Villa Sofia-Cervello, Palermo (PA), Abano, Italy.,General Surgery Department, Policlinico Abano Terme, Abano, Italy
| | - V Martin
- Department of Digestive Surgery and Liver Transplantation, Croix-Rousse University Hospital, Hospices Civils de Lyon, University of Lyon I, Lyon, France
| | - A Paterson
- Department of Surgery, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | - J Rystedt
- Department of Surgery, Skåne University Hospital, Lund University, Lund, Sweden
| | - P Sandström
- Department of Surgery in Linköping, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - A Serrablo
- Department of Surgery, Miguel Servet University Hospital, Zaragoza, Spain
| | - A K Siriwardena
- Hepatobiliary Surgery Unit, Manchester Royal Infirmary, Manchester, UK
| | - H Taflin
- Department of Surgery, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Sahlgrenska University Hospital, Sweden
| | - T M van Gulik
- Department of Surgery, Cancer Centre Amsterdam, Amsterdam UMC, University of Amsterdam, the Netherlands
| | - S Yaqub
- Department of Hepato-Pancreato-Biliary Surgery, Oslo University Hospital, Oslo, Norway
| | - I Özden
- Department of General Surgery, Istanbul University School of Medicine, Istanbul, Turkey
| | - J M Ramia
- Hospital General Universitario de Alicante. ISABIAL Alicante, Spain
| | - C Sturesson
- Division of Surgery, Department of Clinical Science, Intervention and Technology (CLINTEC), Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden
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7
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Loureiro J, Kron P, Temsch EM, Koutecký P, Lopes S, Castro M, Castro S. Isolation of plant nuclei for estimation of nuclear DNA content: Overview and best practices. Cytometry A 2021; 99:318-327. [DOI: 10.1002/cyto.a.24331] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 02/01/2021] [Accepted: 02/24/2021] [Indexed: 11/07/2022]
Affiliation(s)
- João Loureiro
- Centre for Functional Ecology, Department of Life Sciences University of Coimbra Coimbra Portugal
| | - Paul Kron
- Department of Integrative Biology University of Guelph Guelph Ontario Canada
| | - Eva M. Temsch
- Department of Botany and Biodiversity Research University of Vienna Vienna Austria
| | - Petr Koutecký
- Department of Botany Faculty of Science, University of South Bohemia České Budějovice Czechia
| | - Sara Lopes
- Centre for Functional Ecology, Department of Life Sciences University of Coimbra Coimbra Portugal
| | - Mariana Castro
- Centre for Functional Ecology, Department of Life Sciences University of Coimbra Coimbra Portugal
| | - Sílvia Castro
- Centre for Functional Ecology, Department of Life Sciences University of Coimbra Coimbra Portugal
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8
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Kron P, Loureiro J, Castro S, Čertner M. Flow cytometric analysis of pollen and spores: An overview of applications and methodology. Cytometry A 2021; 99:348-358. [PMID: 33625767 DOI: 10.1002/cyto.a.24330] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [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: 10/22/2020] [Revised: 01/21/2021] [Accepted: 02/16/2021] [Indexed: 01/01/2023]
Abstract
Pollen grains are the male gametophytes in a seed-plant life cycle. Their small, particulate nature and crucial role in plant reproduction have made them an attractive object of study using flow cytometry (FCM), with a wide range of applications existing in the literature. While methodological considerations for many of these overlap with those for other tissue types (e.g., general considerations for the measurement of nuclear DNA content), the relative complexity of pollen compared to single cells presents some unique challenges. We consider these here in the context of both the identification and isolation of pollen and its subunits, and the types of research applications. While the discussion here mostly concerns pollen, the general principles described here can be extended to apply to spores in ferns, lycophytes, and bryophytes. In addition to recommendations provided in more general studies, some recurring and notable issues related specifically to pollen and spores are highlighted.
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Affiliation(s)
- Paul Kron
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
| | - João Loureiro
- Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | - Sílvia Castro
- Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | - Martin Čertner
- Department of Botany, Faculty of Science, Charles University, Prague, Czech Republic.,Department of Evolutionary Plant Biology, Institute of Botany of the Czech Academy of Sciences, Průhonice, Czech Republic
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9
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Galbraith D, Loureiro J, Antoniadi I, Bainard J, Bureš P, Cápal P, Castro M, Castro S, Čertner M, Čertnerová D, Chumová Z, Doležel J, Giorgi D, Husband BC, Kolář F, Koutecký P, Kron P, Leitch IJ, Ljung K, Lopes S, Lučanová M, Lucretti S, Ma W, Melzer S, Molnár I, Novák O, Poulton N, Skalický V, Sliwinska E, Šmarda P, Smith TW, Sun G, Talhinhas P, Tárnok A, Temsch EM, Trávníček P, Urfus T. Best practices in plant cytometry. Cytometry A 2021; 99:311-317. [PMID: 33398930 DOI: 10.1002/cyto.a.24295] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 12/07/2020] [Accepted: 12/14/2020] [Indexed: 01/19/2023]
Affiliation(s)
- David Galbraith
- School of Plant Sciences, BIO5 Institute, Arizona Cancer Center, Department of Biomedical Engineering, University of Arizona, Tucson, Arizona, USA.,State Key Laboratory of Cotton Biology, Key Laboratory of Plant Stress Biology, Henan University, School of Life Sciences, State Key Laboratory of Crop Stress Adaptation and Improvement, Kaifeng, China
| | - João Loureiro
- Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | - Ioanna Antoniadi
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Jillian Bainard
- Swift Current Research and Development Centre, Agriculture and Agri-Food Canada, Swift Current, Saskatchewan, Canada
| | - Petr Bureš
- Department of Botany and Zoology, Faculty of Science, Masaryk University, Brno, CZ, Czech Republic
| | - Petr Cápal
- Institute of Experimental Botany of the Czech Academy of Sciences, Olomouc, Czech Republic
| | - Mariana Castro
- Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | - Sílvia Castro
- Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | - Martin Čertner
- Department of Botany, Faculty of Science, Charles University, Prague, Czech Republic.,Czech Academy of Sciences, Institute of Botany, Průhonice, Czech Republic
| | - Dora Čertnerová
- Department of Botany, Faculty of Science, Charles University, Prague, Czech Republic
| | - Zuzana Chumová
- Department of Botany, Faculty of Science, Charles University, Prague, Czech Republic.,Czech Academy of Sciences, Institute of Botany, Průhonice, Czech Republic
| | - Jaroslav Doležel
- Institute of Experimental Botany of the Czech Academy of Sciences, Olomouc, Czech Republic
| | - Debora Giorgi
- Green Biotechnology Laboratory, Biotechnology and Agroindustry Division, Casaccia Research Center, ENEA - Italian National Agency for New Technologies, Energy and Sustainable Economic Development, Rome, Italy
| | - Brian C Husband
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
| | - Filip Kolář
- Department of Botany, Faculty of Science, Charles University, Prague, Czech Republic.,Czech Academy of Sciences, Institute of Botany, Průhonice, Czech Republic
| | - Petr Koutecký
- Department of Botany, Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Paul Kron
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
| | - Ilia J Leitch
- Department of Comparative Plant and Fungal Biology, Royal Botanic Gardens, Richmond, UK
| | - Karin Ljung
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Sara Lopes
- Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | - Magdalena Lučanová
- Czech Academy of Sciences, Institute of Botany, Průhonice, Czech Republic.,Department of Botany, Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Sergio Lucretti
- Green Biotechnology Laboratory, Biotechnology and Agroindustry Division, Casaccia Research Center, ENEA - Italian National Agency for New Technologies, Energy and Sustainable Economic Development, Rome, Italy
| | - Wen Ma
- School of Plant Sciences, BIO5 Institute, Arizona Cancer Center, Department of Biomedical Engineering, University of Arizona, Tucson, Arizona, USA.,State Key Laboratory of Cotton Biology, Key Laboratory of Plant Stress Biology, Henan University, School of Life Sciences, State Key Laboratory of Crop Stress Adaptation and Improvement, Kaifeng, China
| | - Susanne Melzer
- Clinical Trial Centre Leipzig, University Leipzig, Leipzig, Germany.,LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany
| | - István Molnár
- Institute of Experimental Botany of the Czech Academy of Sciences, Olomouc, Czech Republic
| | - Ondřej Novák
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå, Sweden.,Laboratory of Growth Regulators, Institute of Experimental Botany of the Czech Academy of Sciences and Faculty of Science of Palacký University, Olomouc, Czech Republic
| | - Nicole Poulton
- Center for Aquatic Cytometry, Bigelow Laboratory for Ocean Sciences, East Boothbay, Maine, USA
| | - Vladimír Skalický
- Laboratory of Growth Regulators, Institute of Experimental Botany of the Czech Academy of Sciences and Faculty of Science of Palacký University, Olomouc, Czech Republic
| | - Elwira Sliwinska
- Laboratory of Molecular Biology and Cytometry, Department of Agricultural Biotechnology, UTP University of Science and Technology, Bydgoszcz, Poland
| | - Petr Šmarda
- Department of Botany and Zoology, Faculty of Science, Masaryk University, Brno, CZ, Czech Republic
| | - Tyler W Smith
- Ottawa Research and Development Centre, Agriculture and Agri-Food Canada, Ottawa, Ontario, Canada
| | - Guiling Sun
- School of Plant Sciences, BIO5 Institute, Arizona Cancer Center, Department of Biomedical Engineering, University of Arizona, Tucson, Arizona, USA.,State Key Laboratory of Cotton Biology, Key Laboratory of Plant Stress Biology, Henan University, School of Life Sciences, State Key Laboratory of Crop Stress Adaptation and Improvement, Kaifeng, China
| | - Pedro Talhinhas
- LEAF, Linking Landscape, Environment, Agriculture and Food, Instituto Superior de Agronomia, Universidade de Lisboa, Lisbon, Portugal
| | - Attila Tárnok
- LIFE-Leipzig Research Center for Civilization Diseases, University of Leipzig, Leipzig, Germany.,Department of Precision Instruments, Tsinghua University, Beijing, China.,Department for Therapy Validation, Fraunhofer Institute for Cell Therapy and Immunology IZI, Leipzig, Germany
| | - Eva M Temsch
- Department of Botany and Biodiversity Research, University of Vienna, Vienna, Austria
| | - Pavel Trávníček
- Czech Academy of Sciences, Institute of Botany, Průhonice, Czech Republic
| | - Tomáš Urfus
- Department of Botany, Faculty of Science, Charles University, Prague, Czech Republic
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10
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Cronin D, Kron P, Husband BC. The origins and evolutionary history of feral apples in southern Canada. Mol Ecol 2019; 29:1776-1790. [PMID: 31622503 DOI: 10.1111/mec.15277] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [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: 04/01/2019] [Revised: 09/30/2019] [Accepted: 10/03/2019] [Indexed: 12/11/2022]
Abstract
Feral populations of domesticated crops can establish through two nonmutually exclusive pathways: hybridization with native relatives and recruitment of and recombination between known cultivars. The extent and relative importance of these pathways is not known, especially for woody fruit crops. Here, we examined the evolutionary origins of feral populations of Malus domestica (domestic apple) in southern Canada using a population genetic analysis. We characterized genotypes of 578 putative feral apple trees and evaluated them in relation to genotypes of 156 commercial cultivars, 28 non-native, ornamental crabapples and 47 native Malus coronaria trees using 14 microsatellite markers. No feral trees were genetic admixtures between domestic and native Malus; however, a minority of trees were admixed with introduced ornamental Malus. Feral trees and commercial cultivars both occurred in two major genetic groups and seven subgroups distributed throughout all commercial growing regions. A total of 42 cultivars, both heritage and currently grown, occurred in probable parental pairs for feral trees, with nine heritage varieties accounting for 72% of parental assignments. We conclude that feral apples in southern Canada are not products of hybridization with native M. coronaria but we cannot exclude ornamental apple species as contributing to the naturalization process. Nonhybrid feral domestic apples have multiple origins, with a prominent signature of early heritage cultivars. These lineages have spread and coexist throughout Ontario, rather than being derived strictly from local sources.
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Affiliation(s)
- Dane Cronin
- Department of Integrative Biology, University of Guelph, Guelph, ON, Canada
| | - Paul Kron
- Department of Integrative Biology, University of Guelph, Guelph, ON, Canada
| | - Brian C Husband
- Department of Integrative Biology, University of Guelph, Guelph, ON, Canada
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11
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Schneider M, Limani P, Linecker M, Kron P, Petrosky H, Pestalozzi B, Jetter A, Graf R, Humar B, Lehn JM, Clavien PA. First evidence of antitumor activity of ITPP, a novel hypoxia-modifier: Results of a phase Ib trial. Ann Oncol 2018. [DOI: 10.1093/annonc/mdy487.032] [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: 11/14/2022] Open
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12
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Smith TW, Kron P, Martin SL. flowPloidy: An R package for genome size and ploidy assessment of flow cytometry data. Appl Plant Sci 2018; 6:e01164. [PMID: 30131906 PMCID: PMC6055564 DOI: 10.1002/aps3.1164] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Accepted: 05/04/2018] [Indexed: 05/28/2023]
Abstract
PREMISE OF THE STUDY Despite advantages in terms of reproducibility, histogram analysis based on nonlinear regression is rarely used in genome size assessments in plant biology. This is due in part to the lack of a freely available program to implement the procedure. We have developed such a program, the R package flowPloidy. METHODS AND RESULTS flowPloidy builds on the existing statistical tools provided with the R environment. This base provides tools for importing flow cytometry data, fitting nonlinear regressions, and interactively visualizing data. flowPloidy adds tools for building flow cytometry models, fitting the models to histogram data, and producing visual and tabular summaries of the results. CONCLUSIONS flowPloidy fills an important gap in the study of plant genome size. This package will enable plant scientists to apply a more powerful statistical technique for assessing genome size. flowPloidy improves on existing software options by providing a no-cost workflow streamlined for genome size and ploidy determination.
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Affiliation(s)
- Tyler William Smith
- Agriculture and Agri‐Food CanadaNeatby Building960 Carling AvenueOttawaOntarioK1A 0C6Canada
| | - Paul Kron
- Department of Integrative BiologyUniversity of GuelphGuelphOntarioN1G 2W1Canada
| | - Sara L. Martin
- Agriculture and Agri‐Food CanadaNeatby Building960 Carling AvenueOttawaOntarioK1A 0C6Canada
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13
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Schlegel A, Linecker M, Kron P, Györi G, De Oliveira ML, Müllhaupt B, Clavien PA, Dutkowski P. Risk Assessment in High- and Low-MELD Liver Transplantation. Am J Transplant 2017; 17:1050-1063. [PMID: 27676319 DOI: 10.1111/ajt.14065] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [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: 06/24/2016] [Revised: 08/23/2016] [Accepted: 09/21/2016] [Indexed: 01/25/2023]
Abstract
Allocation of liver grafts triggers emotional debates, as those patients, not receiving an organ, are prone to death. We analyzed a high-Model of End-stage Liver Disease (MELD) cohort (laboratory MELD score ≥30, n = 100, median laboratory MELD score of 35; interquartile range 31-37) of liver transplant recipients at our center during the past 10 years and compared results with a low-MELD group, matched by propensity scoring for donor age, recipient age, and cold ischemia time. End points of our study were cumulative posttransplantation morbidity, cost, and survival. Six different prediction models, including donor age x recipient MELD (D-MELD), Difference between listing MELD and MELD at transplant (Delta MELD), donor-risk index (DRI), Survival Outcomes Following Liver Transplant (SOFT), balance-of-risk (BAR), and University of California Los Angeles-Futility Risk Score (UCLA-FRS), were applied in both cohorts to identify risk for poor outcome and high cost. All score models were compared with a clinical-oriented decision, based on the combination of hemofiltration plus ventilation. Median intensive care unit and hospital stays were 8 and 26 days, respectively, after liver transplantation of high-MELD patients, with a significantly increased morbidity compared with low-MELD patients (median comprehensive complication index 56 vs. 36 points [maximum points 100] and double cost [median US$179 631 vs. US$80 229]). Five-year survival, however, was only 8% less than that of low-MELD patients (70% vs. 78%). Most prediction scores showed disappointing low positive predictive values for posttransplantation mortality, such as mortality above thresholds, despite good specificity. The clinical observation of hemofiltration plus ventilation in high-MELD patients was even superior in this respect compared with D-MELD, DRI, Delta MELD, and UCLA-FRS but inferior to SOFT and BAR models. Of all models tested, only the BAR score was linearly associated with complications. In conclusion, the BAR score was most useful for risk classification in liver transplantation, based on expected posttransplantation mortality and morbidity. Difficult decisions to accept liver grafts in high-risk recipients may thus be guided by additional BAR score calculation, to increase the safe use of scarce organs.
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Affiliation(s)
- A Schlegel
- Department of Surgery and Transplantation, Swiss HPB and Transplant Center, University Hospital Zürich, Zürich, Switzerland
| | - M Linecker
- Department of Surgery and Transplantation, Swiss HPB and Transplant Center, University Hospital Zürich, Zürich, Switzerland
| | - P Kron
- Department of Surgery and Transplantation, Swiss HPB and Transplant Center, University Hospital Zürich, Zürich, Switzerland
| | - G Györi
- Department of Surgery and Transplantation, Swiss HPB and Transplant Center, University Hospital Zürich, Zürich, Switzerland
| | - M L De Oliveira
- Department of Surgery and Transplantation, Swiss HPB and Transplant Center, University Hospital Zürich, Zürich, Switzerland
| | - B Müllhaupt
- Department of Gastroenterology and Hepatology, University Hospital Zürich, Zürich, Switzerland
| | - P-A Clavien
- Department of Surgery and Transplantation, Swiss HPB and Transplant Center, University Hospital Zürich, Zürich, Switzerland
| | - P Dutkowski
- Department of Surgery and Transplantation, Swiss HPB and Transplant Center, University Hospital Zürich, Zürich, Switzerland
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14
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Kreiner JM, Kron P, Husband BC. Frequency and maintenance of unreduced gametes in natural plant populations: associations with reproductive mode, life history and genome size. New Phytol 2017; 214:879-889. [PMID: 28134436 DOI: 10.1111/nph.14423] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [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: 10/24/2016] [Accepted: 12/03/2016] [Indexed: 05/20/2023]
Abstract
Fertilization involving unreduced (2n) gametes is considered the dominant mechanism of polyploid formation in angiosperms; however, our knowledge of the prevalence of and evolutionary mechanisms maintaining 2n gametes in natural populations is limited. We hypothesize that 2n gametes are deleterious consequences of meiotic errors maintained by mutation-selection balance and should increase in species with relaxed opportunities for selection on sexual processes (asexuality), reduced efficacy of selection (asexuality, selfing) and increased genome instability (high chromosome number). We used flow cytometry to estimate male 2n gamete production in 60 populations from 24 species of Brassicaceae. We quantified variation in 2n gamete production within and among species, and examined associations with life history, reproductive mode, genome size and chromosomal number while accounting for phylogeny. Most individuals produced < 2% 2n male gametes, whereas a small number had > 5% (up to 85%) production. Variation in 2n gamete production was significant among species and related to reproductive system; asexual species produced significantly more 2n gametes than mixed-mating and outcrossing species. Our results, unique in their multi-species perspective, are consistent with 2n gametes being deleterious but maintained when opportunities for selection are limited. Rare individuals with elevated 2n gamete production may be key contributors to polyploid formation.
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Affiliation(s)
- Julia M Kreiner
- Department of Integrative Biology, University of Guelph, Guelph, ON, Canada, N1G 2W1
| | - Paul Kron
- Department of Integrative Biology, University of Guelph, Guelph, ON, Canada, N1G 2W1
| | - Brian C Husband
- Department of Integrative Biology, University of Guelph, Guelph, ON, Canada, N1G 2W1
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15
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Sora D, Kron P, Husband BC. Genetic and environmental determinants of unreduced gamete production in Brassica napus, Sinapis arvensis and their hybrids. Heredity (Edinb) 2016; 117:440-448. [PMID: 27577694 PMCID: PMC5117845 DOI: 10.1038/hdy.2016.69] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 07/08/2016] [Accepted: 07/13/2016] [Indexed: 11/08/2022] Open
Abstract
Unreduced gametes, sperm or egg cells with the somatic chromosome number, are an important mechanism of polyploid formation and gene flow between heteroploid plants. The meiotic processes leading to unreduced gamete formation are well documented, but the relative influence of environmental and genetic factors on the frequency of unreduced gametes remain largely untested. Furthermore, direct estimates of unreduced gametes based on DNA content are technically challenging and, hence, uncommon. Here, we use flow cytometry to measure the contribution of genetic (hybridization) and environmental (nutrient limitation, wounding) changes to unreduced male gamete production in Brassica napus, Sinapis arvensis and two hybrid lines. Treatments were applied to greenhouse grown plants in a random factorial design, with pollen sampled at two time intervals. Overall, the frequency of unreduced gametes averaged 0.59% (range 0.06-2.17%), plus a single outlier with 27%. Backcrossed hybrids had 39 to 75% higher unreduced gamete production than parental genotypes, averaged across all treatments, although the statistical significance of these differences depended on sampling period and wounding treatment. Unreduced gamete frequencies were higher for the second sampling period than the first. There were no direct effects of wounding or nutrient regime. Our results indicate that both genetic and environmental factors can induce increased unreduced gametes, highlighting the potential importance of environmental heterogeneity and genetic composition of populations in driving polyploid evolution.
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Affiliation(s)
- D Sora
- Department of Biology, Bioscience Complex, Queen's University, Kingston, Ontario, Canada
| | - P Kron
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
| | - B C Husband
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
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16
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Kambakamba P, Linecker M, Alvarez FA, Samaras P, Reiner CS, Raptis DA, Kron P, de Santibanes E, Petrowsky H, Clavien PA, Lesurtel M. Short Chemotherapy-Free Interval Improves Oncological Outcome in Patients Undergoing Two-Stage Hepatectomy for Colorectal Liver Metastases. Ann Surg Oncol 2016; 23:3915-3923. [DOI: 10.1245/s10434-016-5419-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Indexed: 01/07/2023]
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17
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Kron P, Linecker M, Graf R, Clavien PA. Leadership in the 21st century. Eur Surg 2016. [DOI: 10.1007/s10353-016-0419-z] [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: 10/21/2022]
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18
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Affiliation(s)
- Paul Kron
- Department of Integrative Biology; University of Guelph; Guelph Ontario N1G 2W1 Canada
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19
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Abstract
Dynamic preservation strategies such as hypothermic machine perfusion are increasingly discussed to improve liver graft quality before transplantation. This review summarizes current knowledge of this perfusion technique for liver preservation. We discuss optimization of perfusion conditions and current strategies to assess graft quality during cold perfusion. Next, we provide an overview of possible pathways of protection from ischemia-reperfusion injury. Finally, we report on recent clinical applications of human hypothermic machine liver perfusion.
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Affiliation(s)
- A. Schlegel
- Department of Surgery and Transplantation, University Hospital Zürich, Raemistr. 100, 8091 Zurich, Switzerland
| | - P. Kron
- Department of Surgery and Transplantation, University Hospital Zürich, Raemistr. 100, 8091 Zurich, Switzerland
| | - P. Dutkowski
- Department of Surgery and Transplantation, University Hospital Zürich, Raemistr. 100, 8091 Zurich, Switzerland
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20
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Kron P, Husband BC. Distinguishing 2N gamete nuclei from doublets in pollen using flow cytometry and pulse analysis. Cytometry A 2015; 87:943-57. [DOI: 10.1002/cyto.a.22696] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2015] [Revised: 04/06/2015] [Accepted: 05/04/2015] [Indexed: 11/11/2022]
Affiliation(s)
- Paul Kron
- Department of Integrative Biology; University of Guelph; Ontario N1G 2W1 Canada
| | - Brian C. Husband
- Department of Integrative Biology; University of Guelph; Ontario N1G 2W1 Canada
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21
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Kambakamba P, Slankamenac K, Tschuor C, Kron P, Wirsching A, Maurer K, Petrowsky H, Clavien PA, Lesurtel M. Epidural analgesia and perioperative kidney function after major liver resection. Br J Surg 2015; 102:805-12. [PMID: 25877255 DOI: 10.1002/bjs.9810] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Revised: 02/07/2015] [Accepted: 02/19/2015] [Indexed: 02/06/2023]
Abstract
BACKGROUND Epidural analgesia (EDA) is a common analgesia regimen in liver resection, and is accompanied by sympathicolysis, peripheral vasodilatation and hypotension in the context of deliberate intraoperative low central venous pressure. This associated fall in mean arterial pressure may compromise renal blood pressure autoregulation and lead to acute kidney injury (AKI). This study investigated whether EDA is a risk factor for postoperative AKI after liver surgery. METHODS The incidence of AKI was investigated retrospectively in patients who underwent liver resection with or without EDA between 2002 and 2012. Univariable and multivariable analyses were performed including recognized preoperative and intraoperative predictors of posthepatectomy renal failure. RESULTS A series of 1153 patients was investigated. AKI occurred in 8·2 per cent of patients and was associated with increased morbidity (71 versus 47·3 per cent; P = 0·003) and mortality (21 versus 0·3 per cent; P < 0·001) rates. The incidence of AKI was significantly higher in the EDA group (10·1 versus 3·7 per cent; P = 0·003). Although there was no significant difference in the incidence of AKI between patients undergoing minor hepatectomy with or without EDA (5·2 versus 2·7 per cent; P = 0·421), a substantial difference in AKI rates occurred in patients undergoing major hepatectomy (13·8 versus 5·0 per cent; P = 0·025). In multivariable analysis, EDA remained an independent risk factor for AKI after hepatectomy (P = 0·040). CONCLUSION EDA may be a risk factor for postoperative AKI after major hepatectomy.
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Affiliation(s)
- P Kambakamba
- Department of Surgery, Swiss Hepatopancreatobiliary and Transplantation Center, Zurich, Switzerland
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22
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McAllister C, Blaine R, Kron P, Bennett B, Garrett H, Kidson J, Matzenbacher B, Glotzbach A, Miller AJ. Environmental correlates of cytotype distribution in Andropogon gerardii (Poaceae). Am J Bot 2015; 102:92-102. [PMID: 25587152 DOI: 10.3732/ajb.1400296] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
UNLABELLED • PREMISE OF THE STUDY Information about geographic distribution of cytotypes can provide insight into the origin and maintenance of autopolyploid complexes and builds a foundation for understanding cytotype differentiation and the dynamics of mixed-ploidy populations. Here, we investigate environmental correlates of the geographic distributions of 6x and 9x individuals in the ecologically dominant grass Andropogon gerardii to examine the role of climate in shaping patterns of cytotype distribution in this species.• METHODS Flow cytometry was used to estimate ploidy level in 352 individuals from 32 populations across North America. Ecological differentiation of cytotypes was tested by relating BIOCLIM variables to cytotype distribution using principal components analysis and partial linear regression.• KEY RESULTS Broad geographic sampling confirmed two primary cytotypes-6x (hexaploid) and 9x (enneaploid)-and revealed that 9x plants are more common than previously thought. Enneaploids occur frequently in the southern portions of the range, with hexaploids dominating in northern regions. Mixed-ploidy populations were common (46.9%). Principal components analysis and partial linear regression indicated that reduced summer precipitation and increased variation in diurnal and seasonal temperature range were significant predictors of the frequency of 9x plants in a population.• CONCLUSIONS Results indicate that (1) geographic distribution of 6x and 9x individuals is nonrandom; (2) environmental variables are associated with cytotype distribution in A. gerardii; and (3) nearly half of populations surveyed include both 6x and 9x individuals. The persistence of mixed-ploidy populations may reflect a combination of recurrent polyploid formation and the prevalence of clonal reproduction.
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Affiliation(s)
- Christine McAllister
- Principia College, Department of Biology and Natural Resources, Elsah, Illinois 62028 USA Saint Louis University, Department of Biology, 3507 Macelwane Hall, St. Louis, Missouri 63103 USA
| | - Russell Blaine
- Southern Illinois University, Edwardsville, 1 Hairpin Drive, Edwardsville, Illinois 62025 USA
| | - Paul Kron
- University of Guelph, Department of Integrative Biology, 50 Stone Road East, Guelph, Ontario, Canada, NIG 2W1
| | - Brent Bennett
- Principia College, Department of Biology and Natural Resources, Elsah, Illinois 62028 USA
| | - Heidi Garrett
- Principia College, Department of Biology and Natural Resources, Elsah, Illinois 62028 USA
| | - Jennifer Kidson
- Principia College, Department of Biology and Natural Resources, Elsah, Illinois 62028 USA
| | - Blanda Matzenbacher
- Principia College, Department of Biology and Natural Resources, Elsah, Illinois 62028 USA
| | - Anna Glotzbach
- Principia College, Department of Biology and Natural Resources, Elsah, Illinois 62028 USA
| | - Allison J Miller
- Saint Louis University, Department of Biology, 3507 Macelwane Hall, St. Louis, Missouri 63103 USA
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Kron P, Kwok A, Husband BC. Flow cytometric analysis of pollen grains collected from individual bees provides information about pollen load composition and foraging behaviour. Ann Bot 2014; 113:191-197. [PMID: 24232381 PMCID: PMC3864728 DOI: 10.1093/aob/mct257] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [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: 06/04/2013] [Accepted: 09/13/2013] [Indexed: 05/30/2023]
Abstract
BACKGROUND AND AIMS Understanding the species composition of pollen on pollinators has applications in agriculture, conservation and evolutionary biology. Current identification methods, including morphological analysis, cannot always discriminate taxa at the species level. Recent advances in flow cytometry techniques for pollen grains allow rapid testing of large numbers of pollen grains for DNA content, potentially providing improved species resolution. METHODS A test was made as to whether pollen loads from single bees (honey-bees and bumble-bees) could be classified into types based on DNA content, and whether good estimates of proportions of different types could be made. An examination was also made of how readily DNA content can be used to identify specific pollen species. KEY RESULTS The method allowed DNA contents to be quickly found for between 250 and 9391 pollen grains (750-28 173 nuclei) from individual honey-bees and between 81 and 11 512 pollen grains (243-34 537 nuclei) for bumble-bees. It was possible to identify a minimum number of pollen species on each bee and to assign proportions of each pollen type (based on DNA content) present. CONCLUSIONS The information provided by this technique is promising but is affected by the complexity of the pollination environment (i.e. number of flowering species present and extent of overlap in DNA content). Nevertheless, it provides a new tool for examining pollinator behaviour and between-species or cytotype pollen transfer, particularly when used in combination with other morphological, chemical or genetic techniques.
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Sabara HA, Kron P, Husband BC. Cytotype coexistence leads to triploid hybrid production in a diploid-tetraploid contact zone of Chamerion angustifolium (Onagraceae). Am J Bot 2013; 100:962-970. [PMID: 23629844 DOI: 10.3732/ajb.1200583] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
PREMISE OF THE STUDY Polyploids are often geographically segregated from their diploid progenitors, but the extent of sympatry and the consequences for reproductive isolation and coexistence are rarely quantified. • METHODS In this study, we document the distribution and co-occurrence of diploid and tetraploid Chamerion angustifolium among 57 populations within the diploid-tetraploid contact zone in the Canadian Rocky Mountains. Rates of hybrid mating in mixed-ploidy populations were inferred from the frequency of triploid offspring in open-pollinated seed families. • KEY RESULTS Twenty-three of 57 populations sampled contained a single cytotype; 20 (87%) were tetraploid and three (13%) were diploid. Thirty-four populations (60%) contained multiple ploidies. Diploid and tetraploid plants occurred in all mixed-ploidy populations; triploids occurred in 13 populations and averaged 1.4% of plants per population. The proportion of tetraploids in a population was negatively related to elevation (partial regression: F = 27.2, P <0.0001) and latitude (partial regression: F = 17.4, P < 0.0001). Triploids were detected in seed from all eight mixed-ploidy populations sampled ( = 3.7% of seed per population), comprising 7% of that expected with random mating (G = 2589.2, df = 1, P <0.0001, n = 2628), and were more often produced by diploid maternal parents than tetraploid parents. • CONCLUSIONS Our results indicate that tetraploids regularly coexist with diploids in the contact zone and that this coexistence is likely promoted by both strong reproductive isolation and asymmetric intercytotype mating between diploid and tetraploid C. angustifolium.
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Affiliation(s)
- Holly A Sabara
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada N1G 2W1
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25
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Kron P, Husband BC. Using flow cytometry to estimate pollen DNA content: improved methodology and applications. Ann Bot 2012; 110:1067-78. [PMID: 22875815 PMCID: PMC3448423 DOI: 10.1093/aob/mcs167] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [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: 03/06/2012] [Accepted: 05/24/2012] [Indexed: 05/23/2023]
Abstract
BACKGROUND AND AIMS Flow cytometry has been used to measure nuclear DNA content in pollen, mostly to understand pollen development and detect unreduced gametes. Published data have not always met the high-quality standards required for some applications, in part due to difficulties inherent in the extraction of nuclei. Here we describe a simple and relatively novel method for extracting pollen nuclei, involving the bursting of pollen through a nylon mesh, compare it with other methods and demonstrate its broad applicability and utility. METHODS The method was tested across 80 species, 64 genera and 33 families, and the data were evaluated using established criteria for estimating genome size and analysing cell cycle. Filter bursting was directly compared with chopping in five species, yields were compared with published values for sonicated samples, and the method was applied by comparing genome size estimates for leaf and pollen nuclei in six species. KEY RESULTS Data quality met generally applied standards for estimating genome size in 81 % of species and the higher best practice standards for cell cycle analysis in 51 %. In 41 % of species we met the most stringent criterion of screening 10 000 pollen grains per sample. In direct comparison with two chopping techniques, our method produced better quality histograms with consistently higher nuclei yields, and yields were higher than previously published results for sonication. In three binucleate and three trinucleate species we found that pollen-based genome size estimates differed from leaf tissue estimates by 1·5 % or less when 1C pollen nuclei were used, while estimates from 2C generative nuclei differed from leaf estimates by up to 2·5 %. CONCLUSIONS The high success rate, ease of use and wide applicability of the filter bursting method show that this method can facilitate the use of pollen for estimating genome size and dramatically improve unreduced pollen production estimation with flow cytometry.
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Affiliation(s)
- Paul Kron
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada.
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Affiliation(s)
- Paul Kron
- Department of Integrative Biology, University of Guelph, Ontario, Canada N1G 2W1; ,
| | - Jan Suda
- Department of Botany, Faculty of Science, Charles University in Prague, CZ-128 01, Czech Republic and Institute of Botany, Academy of Sciences of the Czech Republic, CZ-252 43, Czech Republic;
| | - Brian C. Husband
- Department of Integrative Biology, University of Guelph, Ontario, Canada N1G 2W1; ,
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Abstract
* Information on angiosperm sex ratios has largely been restricted to surveys of flowering individuals. These often deviate from equality, with male bias more commonly reported. Female-biased sex ratios are concentrated in a few taxa and have been linked to the possession of heteromorphic sex chromosomes and bias introduced during the gametophytic stage of the life cycle. It has been proposed that differences in gamete quantity and quality could give rise to female bias, although there is no direct evidence with which to evaluate this possibility. * Here, we use flow cytometry to investigate microgametophytic 'sex ratios' in a flowering plant. We demonstrate that differences in DNA content between the sexes in Rumex nivalis, a species with heteromorphic sex chromosomes, make it possible to distinguish female- vs male-determining pollen nuclei. * We found a small but significant female bias in microgametophytes produced by males (mean 0.515) with significant variation among family means (range 0.463-0.586), and 18 of 22 families averaging > 0.50. * The observed female bias at the gametophytic stage of the life cycle is consistent with the direction of bias previously reported for seeds and vegetative and reproductive plants in wild populations of R. nivalis, but is insufficient to fully explain the degree of bias.
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Affiliation(s)
- Ivana Stehlik
- Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks St., Toronto, Ontario, Canada M5S 3B2
| | - Paul Kron
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada N1G 2W1
| | - Spencer C H Barrett
- Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks St., Toronto, Ontario, Canada M5S 3B2
| | - Brian C Husband
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada N1G 2W1
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Routley MB, Kron P, Husband BC. The consequences of clone size for paternal and maternal success in domestic apple (Malus x domestica). Am J Bot 2004; 91:1326-1332. [PMID: 21652365 DOI: 10.3732/ajb.91.9.1326] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Clonal growth in plants can increase pollen and ovule production per genet. However, paternal and maternal reproductive success may not increase because within-clone pollination (geitonogamy) can reduce pollen export to adjacent clones (pollen discounting) and pollen import to the central ramets (pollen limitation). The relationship between clone size and mating success was investigated using clones of Malus × domestica at four orchards (blocks of 1-5 rows of trees). For each block, maternal function was measured as fruit and seed set in all rows and paternal function as siring rate estimated from isozyme profiles in the first row of the adjacent block. Expected relations between reproductive success and clone size were generated from simulations and data on pollen dispersal in this species. Siring rate per clone averaged 70% and did not increase significantly with block size, consistent with simulations of pollen dispersal under pollen discounting. Simulations also indicated that the ratio of compatible to incompatible pollen received by a tree should decline with increased block size and from the periphery to the center of blocks. However, female function was not significantly reduced among block sizes or within blocks. The results suggest that paternal function may be more sensitive to the effects of clonality than female function.
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Affiliation(s)
- Matthew B Routley
- Department of Botany, University of Guelph, Guelph, Ontario, Canada N1G 2W1
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30
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Abstract
Protocols were developed for both chromosome counts and flow cytometry to assess ploidy level and DNA content for populations of Arabidopsis lyrata L. sampled from Europe (Arabidopsis lyrata subsp. petraea), North America (Arabidopsis lyrata subsp. lyrata), and Japan (Arabidopsis lyrata subsp. kawasakiana). Ploidy variation within this species is not clear, with previous studies having documented both diploid and tetraploid populations. Chromosome counts in this study confirmed ploidy expectations for all populations examined. Individuals from Iceland and North America were diploid (2n = 2x = 16), whereas those from Japanese and Austrian populations were tetraploid (2n = 4x = 32). Flow cytometry was also used successfully to distinguish between ploidy levels, but the need to calibrate DNA content measures with chromosome counts was demonstrated by a deviation from the expected 2:1 ratio between tetraploid and diploid values among European populations (A. lyrata subsp. petraea). This deviation might be explained by a hybrid (allopolyploid) origin or by genomic changes following polyploidization, emphasizing the dynamic nature of polyploid genomes. Variation in DNA content among families was found only for North American populations, but these individuals were sampled from a broader geographic range than those from other regions.Key words: cytogenetics, flow cytometry, polyploidy, Arabidopsis lyrata, genome size, chromosome counts.
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Lippmann-Grob B, Bierwirth RA, Kron P, Leinhos B, Funke K, Huptas M, Grüneberg M, Weich KW, Münscher C, Potthoff F. Patientenklassifikation und Risikoprofilanalysen bei Typ-2-Diabetikern in der Schwerpunktpraxis. Dtsch Med Wochenschr 2004; 129:75-81. [PMID: 14724780 DOI: 10.1055/s-2004-816292] [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: 10/26/2022]
Abstract
BACKGROUND AND OBJECTIVE Disease management programs (DMP) e. g. for diabetes mellitus, should be the clinical and economic basis for a structured treatment. This article shows results of specialized outpatient treatment using a risk factor depending patient classification. PATIENTS AND METHODS Diabetes associated co-morbidities, micro- and macrovascular complications, the results and findings of blood pressure and metabolism of glucose and lipids, as well as all treatment-associated costs of 5245 type 2 diabetics were collected for a period of 12 months, accompanied by different measures of quality control. For documentation in the centres, all available original data were used as local data sources. RESULTS The patient classification system, on which diabetic risk profiles are based, covered 74.3 % of all type 2 diabetic patients. Daily direct costs for all treatment measures ranged between EUR 4.79 (primary prevention) and EUR 8.96 for patients suffering from advanced diabetic foot syndrome. Most of the treatment costs arose from prescriptions of pharmaceuticals, other remedies and aids. Specific strategies of therapy were both related to the severity of co-morbidities and the time since manifestation of diabetes (r = 0.486; p < 0.01, two-sided). The share of patients receiving diet and exercise only decreased from 22.8 % (primary prevention) to below 10 % of patients suffering from microvascular complications. Simultaneously, the share of patients receiving insulin increased up to 81.8 % of patients suffering from advanced diabetic retinopathy. CONCLUSION The risk profile specific variation in the results clearly shows the need of a risk factor depending classification system for type 2 diabetes, which could be useful to reform and focus the system of compensating payments between health insurance companies more and more on morbidity, or on risk profiles.
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Kron P, Stewart SC, Back A. Self-compatibility, autonomous self-pollination, and insect-mediated pollination in the clonal species Iris versicolor. ACTA ACUST UNITED AC 1993. [DOI: 10.1139/b93-182] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In clonal species, sexual and asexual systems interact to create a hierarchy of reproduction. For example, self-pollination can occur within pollination units, flowers, ramets, or clones. We investigated the reproductive biology of a natural population of Iris versicolor using pollination manipulations and observations of pollinator behaviour. We found that (i) individuals were completely self-compatible, (ii) selfing rates were close to 100%, (iii) autonomous self-pollination can occur through stigma–anther contact or wind action, (iv) most seed and fruit set can be accounted for by insect pollination, and (v) facilitated self-pollination likely occurs because pollinators frequently visit more than one pollination unit within a flower. Our observations showed that flowers pass through three stages: (i) a male stage (in which pollen is freely available, but stigmas are inaccessible, preventing autogamy); (ii) a female stage (in which stigma flaps have reflexed and are receptive, but pollinators may have already removed most pollen grains, structuring opportunities for geitonogamy); and (iii) a strongly autogamous stage (in which stigma flaps have curled back to contact anthers, leading to delayed autonomous self-pollination). This hierarchy of relatedness among mates determines the genetic consequences of vegetative and sexual reproduction in clonal plants and influences their evolution. Key words: Iris, self-incompatibility, reproductive biology, clonal, pollination.
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Kron P, M'Kaouar R, Abeille JF, Michel JR. [Pseudotumor focal xanthogranulomatous pyelonephritis in adults. Role of imaging technics in the diagnosis]. J Radiol 1988; 69:423-30. [PMID: 3047373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Based on 8 personal cases, pseudo-tumoral xanthogranulomatous pyelonephritis is reviewed with emphasis on diagnosis. The condition is a particular form of chronic renal suppuration of histologic definition (combined lesions of chronic pyelonephritis and xanthogranulomatous foam cells). Two forms are recognized: one diffuse, fairly frequent form corresponding to a pyonephrosis, and a pseudo tumoral focal form, the only type discussed in this report, which raises the problem of diagnosis of a renal mass that requires the application of all currently available exploration means to define its true nature. Intravenous urography, ultrasound and CT scan imaging show a non-specific mass of variable character. Selective renal arteriography sometimes shows inflammatory type vascularization, a valuable aid but again non-specific. Puncture biopsy has been used by few authors. However, the presence of a renal mass associated with a chronic pyelonephritis, lithiasis and recurrent episodes of urinary infection should suggest the diagnosis and make use of imaging techniques to detect the affection and adapt therapy, major oncologic surgery being of no utility. Perhaps NMR imaging will provide a step forward in tissue characterization, but it is too early to say.
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Affiliation(s)
- P Kron
- Service de Radiologie Urinaire Hôpital Necker, Paris
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Lhospitel S, Abeille JF, Kron P, Michel JR. [Calcified masses of the kidney. Apropos of 58 cases]. J Radiol 1988; 69:365-76. [PMID: 3042998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Case reports were analyzed of patients with calcified renal masses observed in the department since 1968. Of the 65 radiologic reports reviewed, 7 were rejected since the course since diagnosis was unknown. Of the 58 case reports studied, 34 were of masses of certain diagnosis, 12 undetermined, 7 of masses in polycystic kidneys, 3 in tuberculous kidneys and 3 probably calcified hematomas. Analysis involved only those masses of proven diagnosis. Results confirmed the absence of specificity in favor of the cyst of peripheral character of calcifications: 33% of these masses were cancers. The existence of tissue calcification is synonymous of a solid mass, nearly always malignant (92% of cases). For peripherally calcified masses, arteriography was not sufficient to affirm benign nature of lesions, most of these masses having a particularly poorly vascularized or even avascular appearance. In these cases angiotensin was of special interest. Ultrasound imaging proved to be a reliable and perfectly sensitive examination. The presence of calcifications rarely interfered with study of tumoral contents. CT scan imaging and puncture biopsy were also perfectly sensitive and reliable examinations. Because of the high frequency of cancers in masses with peripheral calcification, all these masses should be surgically explored or at least punctured. Although a "benign" CT scan image appears sufficient to affirm the benign nature, this still requires more ample confirmation.
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Affiliation(s)
- S Lhospitel
- Service de Radiologie urinaire, Hôpital Necker, Paris
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35
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Vanel D, Tcheng S, Contesso G, Zafrani B, Kalifa C, Dubousset J, Kron P. The radiological appearances of telangiectatic osteosarcoma. A study of 14 cases. Skeletal Radiol 1987; 16:196-200. [PMID: 3473690 DOI: 10.1007/bf00356952] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Fourteen telangiectatic osteosarcomas are reported. They are rare, clinically and radiologically aggressive lesions, involving mainly the femurs of young patients, often misdiagnosed as aneurysmal bone cysts. An explanation for a characteristic early radiological appearance consisting of regular parallel striations of the shaft is suggested.
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