11 results on '"Visser DS"'
Search Results
2. Ischemic-type biliary lesions after human liver transplantation are preceded by abnormal bile composition
- Author
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Buis, CI, primary, Geuken, E, additional, Visser, DS, additional, Leuvenink, HGD, additional, Slooff, MJH, additional, and Porte, RJ, additional
- Published
- 2006
- Full Text
- View/download PDF
3. Altered bile composition after liver transplantation is associated with the development of nonanastomotic biliary strictures.
- Author
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Buis CI, Geuken E, Visser DS, Kuipers F, Haagsma EB, Verkade HJ, and Porte RJ
- Subjects
- Adult, Alanine Transaminase blood, Aspartate Aminotransferases blood, Bile metabolism, Bile Acids and Salts metabolism, Biliary Tract metabolism, Cholestasis etiology, Cholestasis metabolism, Cholestasis pathology, Cholesterol metabolism, Cohort Studies, Constriction, Pathologic metabolism, Female, Humans, Male, Middle Aged, Phospholipids metabolism, Prospective Studies, gamma-Glutamyltransferase blood, Bile chemistry, Biliary Tract pathology, Constriction, Pathologic etiology, Constriction, Pathologic pathology, Liver Transplantation, Postoperative Complications
- Abstract
Background/aims: Nonanastomotic biliary strictures are troublesome complications after liver transplantation. The pathogenesis of NAS is not completely clear, but experimental studies suggest that bile salt toxicity is involved., Methods: In one hundred and eleven adult liver transplants, bile samples were collected daily posttransplantation for determination of bile composition. Expression of bile transporters was studied perioperatively., Results: Nonanastomotic biliary strictures were detected in 14 patients (13%) within one year after transplantation. Patient and donor characteristics and postoperative serum liver enzymes were similar between patients who developed nonanastomotic biliary strictures and those who did not. Secretions of bile salts, phospholipids and cholesterol were significantly lower in patients who developed strictures. In parallel, biliary phospholipids/bile salt ratio was lower in patients developing strictures, suggestive for increased bile cytotoxicity. There were no differences in bile salt pool composition or in hepatobiliary transporter expression., Conclusions: Although patients who develop nonanastomotic biliary strictures are initially clinically indiscernible from patients who do not develop nonanastomotic biliary strictures, the biliary bile salts and phospholipids secretion, as well as biliary phospholipids/bile salt ratio in the first week after transplantation, was significantly lower in the former group. This supports the concept that bile cytotoxicity is involved in the pathogenesis of nonanastomotic biliary strictures.
- Published
- 2009
- Full Text
- View/download PDF
4. The role of bile salt toxicity in the pathogenesis of bile duct injury after non-heart-beating porcine liver transplantation.
- Author
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Yska MJ, Buis CI, Monbaliu D, Schuurs TA, Gouw AS, Kahmann ON, Visser DS, Pirenne J, and Porte RJ
- Subjects
- ATP Binding Cassette Transporter, Subfamily B biosynthesis, ATP Binding Cassette Transporter, Subfamily B genetics, ATP Binding Cassette Transporter, Subfamily B, Member 11, ATP-Binding Cassette Transporters biosynthesis, ATP-Binding Cassette Transporters genetics, Animals, Bile Acids and Salts metabolism, Biopsy, Cholestasis, Intrahepatic metabolism, Cholestasis, Intrahepatic mortality, Disease Models, Animal, Female, Gene Expression, Liver Transplantation mortality, Liver Transplantation pathology, RNA, Messenger genetics, Reverse Transcriptase Polymerase Chain Reaction, Risk Factors, Severity of Illness Index, Survival Rate, Swine, Bile Acids and Salts toxicity, Bile Ducts, Intrahepatic injuries, Cholestasis, Intrahepatic etiology, Liver Transplantation adverse effects
- Abstract
Background: Intrahepatic bile duct strictures are a serious complication after non-heart-beating (NHB) liver transplantation. Bile salt toxicity has been identified as an important factor in the pathogenesis of bile duct injury and cholangiopathies. The role of bile salt toxicity in the development of biliary strictures after NHB liver transplantation is unclear., Methods: In a porcine model of NHB liver transplantation, we studied the effect of different periods of warm ischemia in the donor on bile composition and subsequent bile duct injury after transplantation. After induction of cardiac arrest in the donor, liver procurement was delayed for 0 min (group A), 15 min (group B), or more or equal to 30 min (group C). Livers were subsequently transplanted after 4 hr of cold preservation. In the recipients, bile flow was measured, and bile samples were collected daily to determine the bile salt-to-phospholipid ratio. Severity of bile duct injury was semiquantified by using a histologic grading scale., Results: Posttransplantation survival was directly related to the duration of warm ischemia in the donor. The bile salt-to-phospholipid ratio in bile produced early after transplantation was significantly higher in group C, compared with group A and B. Histopathologic condition showed the highest degree of bile duct injury in group C., Conclusion: Prolonged warm ischemia in NHB donors is associated with the formation of toxic bile after transplantation, with a high biliary bile salt-to-phospholipid ratio. These data suggest that bile salt toxicity contributes to the pathogenesis of bile duct injury after NHB liver transplantation.
- Published
- 2008
- Full Text
- View/download PDF
5. Heme oxygenase-1 genotype of the donor is associated with graft survival after liver transplantation.
- Author
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Buis CI, van der Steege G, Visser DS, Nolte IM, Hepkema BG, Nijsten M, Slooff MJ, and Porte RJ
- Subjects
- Adult, Biopsy, Female, Genotype, Humans, Liver enzymology, Liver Function Tests, Liver Transplantation immunology, Liver Transplantation pathology, Male, Middle Aged, Polymorphism, Genetic, RNA, Messenger genetics, Graft Survival physiology, Heme Oxygenase-1 genetics, Liver Transplantation physiology, Polymorphism, Single Nucleotide, Tissue Donors
- Abstract
Heme oxygenase-1 (HO-1) has been suggested as a cytoprotective gene during liver transplantation. Inducibility of HO-1 is modulated by a (GT)(n) polymorphism and a single nucleotide polymorphism (SNP) A(-413)T in the promoter. Both a short (GT)(n) allele and the A-allele have been associated with increased HO-1 promoter activity. In 308 liver transplantations, we assessed donor HO-1 genotype and correlated this with outcome variables. For (GT)(n) genotype, livers were divided into two classes: short alleles (<25 repeats; class S) and long alleles (> or =25 repeats; class L). In a subset, hepatic messenger ribonucleic acid (mRNA) expression was correlated with genotypes. Graft survival at 1 year was significantly better for A-allele genotype compared to TT-genotype (84% vs. 63%, p = 0.004). Graft loss due to primary dysfunction (PDF) occurred more frequently in TT-genotype compared to A-receivers (p = 0.03). Recipients of a liver with TT-genotype had significantly higher serum transaminases after transplantation and hepatic HO-1 mRNA levels were significantly lower compared to the A-allele livers (p = 0.03). No differences were found for any outcome variable between class S and LL-variant of the (GT)(n) polymorphism. Haplotype analysis confirmed dominance of the A(-413)T SNP over the (GT)(n) polymorphism. In conclusion, HO-1 genotype is associated with outcome after liver transplantation. These findings suggest that HO-1 mediates graft survival after liver transplantation.
- Published
- 2008
- Full Text
- View/download PDF
6. Spatiotemporal expression of heme oxygenase-1 detected by in vivo bioluminescence after hepatic ischemia in HO-1/Luc mice.
- Author
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Su H, van Dam GM, Buis CI, Visser DS, Hesselink JW, Schuurs TA, Leuvenink HG, Contag CH, and Porte RJ
- Subjects
- Animals, Feasibility Studies, Heme Oxygenase-1 genetics, Immunohistochemistry methods, Luciferases genetics, Male, Mice, Mice, Transgenic, RNA, Messenger metabolism, Reperfusion Injury enzymology, Staining and Labeling, Time Factors, Tissue Distribution, Warm Ischemia, Heme Oxygenase-1 metabolism, Ischemia enzymology, Liver blood supply, Liver enzymology, Luminescent Measurements
- Abstract
Upregulation of heme oxygenase-1 (HO-1) has been proposed as a critical mechanism protecting against cellular stress during liver transplantation, providing a potential target for new therapeutic interventions. We investigated the feasibility of in vivo bioluminescence imaging (BLI) to noninvasively quantify the spatiotemporal expression of HO-1 after warm hepatic ischemia in living animals. Luciferase activity was measured by BLI as an index of HO-1 transcription in transgenic reporter mice (Ho1-luc) at standardized time points after 60 minutes of warm hepatic ischemia. HO-1 mRNA levels were measured in postischemic livers of mice sacrificed at the same time points in separate experiments. Bioluminescent signals from postischemic liver lobes were first detected at 3 hours after reperfusion. Peak levels were reached at 9 hours, after which bioluminescent activity declined and returned to baseline values at 48 hours after reperfusion. Upregulation of HO-1 as detected by in vivo BLI was preceded by increased HO-1 mRNA expression and confirmed by enhanced immunohistochemical staining of hepatocytes. In conclusion, this study shows that in vivo BLI allows a sensitive assessment of HO-1 expression after hepatic ischemia in living animals. The capability of whole-body temporal imaging of HO-1 expression provides a valuable tool in the development of novel strategies to modulate HO-1 expression in liver transplantation., ((c) 2006 AASLD)
- Published
- 2006
- Full Text
- View/download PDF
7. Hepatic expression of ABC transporters G5 and G8 does not correlate with biliary cholesterol secretion in liver transplant patients.
- Author
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Geuken E, Visser DS, Leuvenink HG, de Jong KP, Peeters PM, Slooff MJ, Kuipers F, and Porte RJ
- Subjects
- ATP Binding Cassette Transporter, Subfamily B genetics, ATP Binding Cassette Transporter, Subfamily G, Member 5, ATP Binding Cassette Transporter, Subfamily G, Member 8, ATP-Binding Cassette Transporters genetics, Adolescent, Adult, Aged, Female, Humans, Lipoproteins genetics, Male, Middle Aged, Phospholipids metabolism, Postoperative Period, RNA, Messenger metabolism, ATP-Binding Cassette Transporters metabolism, Bile metabolism, Cholesterol metabolism, Lipoproteins metabolism, Liver metabolism, Liver Transplantation
- Abstract
The adenosine triphosphate (ATP)-binding cassette (ABC)-transporters ABCG5 and ABCG8 have been shown to mediate hepatic and intestinal excretion of cholesterol. In various (genetically modified) murine models, a strong relationship was found between hepatic expression of ABCG5/ABCG8 and biliary cholesterol content. Our study aimed to relate levels of hepatic expression of ABCG5 and ABCG8 to biliary excretion of cholesterol in man. From 24 patients who had received a liver transplant, bile samples were collected daily after transplantation over a 2-week period to determine biliary composition. Expression of ABCG5, ABCG8, MDR3, and BSEP was assessed by real-time polymerase chain reaction (PCR) in liver biopsy specimens collected before and after transplantation. Levels of hepatic ABCG5, ABCG8, and MDR3 messenger RNA (mRNA) were strongly correlated. After transplantation, the biliary secretion rate of cholesterol continuously increased, coinciding with gradual increases in bile salt and phospholipid secretion. In contrast, hepatic levels of ABCG5 and ABCG8 mRNA remained unchanged. Surprisingly, no correlation was found between the hepatic expression of ABCG5 and ABCG8 and rates of biliary cholesterol secretion, normalized for biliary phospholipid secretion. As expected, the concentration of biliary phospholipids correlated well with MDR3 expression. In conclusion, the strong relationship between ABCG5 and ABCG8 gene expression is consistent with the coordinate regulation of both genes, and in line with heterodimerization of both proteins into a functional transporter. Hepatic ABCG5/ABCG8 expression, at least during the early phase after transplantation, is not directly related to biliary cholesterol secretion in humans. This finding suggests the existence of alternative pathways for the hepatobiliary transport of cholesterol that are not controlled by ABCG5/ABCG8.
- Published
- 2005
- Full Text
- View/download PDF
8. Expression of heme oxygenase-1 in human livers before transplantation correlates with graft injury and function after transplantation.
- Author
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Geuken E, Buis CI, Visser DS, Blokzijl H, Moshage H, Nemes B, Leuvenink HG, de Jong KP, Peeters PM, Slooff MJ, and Porte RJ
- Subjects
- Adult, Cold Temperature, Female, Gene Frequency, Genotype, Graft Survival physiology, Heme Oxygenase-1, Humans, Ischemia enzymology, Ischemia pathology, Male, Membrane Proteins, Middle Aged, Promoter Regions, Genetic, RNA, Messenger metabolism, Reperfusion Injury pathology, Reperfusion Injury prevention & control, Gene Expression Regulation, Enzymologic physiology, Heme Oxygenase (Decyclizing) genetics, Ischemia prevention & control, Liver enzymology, Liver Transplantation, Reperfusion Injury enzymology
- Abstract
Upregulation of heme oxygenase-1 (HO-1) has been proposed as an adaptive mechanism protecting against ischemia/reperfusion (I/R) injury. We investigated HO-1 expression in 38 human liver transplants and correlated this with I/R injury and graft function. Before transplantation, median HO-1 mRNA levels were 3.4-fold higher (range: 0.7-9.3) in donors than in normal controls. Based on the median value, livers were divided into two groups: low and high HO-1 expression. These groups had similar donor characteristics, donor serum transaminases, cold ischemia time, HSP-70 expression and the distribution of HO-1 promoter polymorphism. After reperfusion, HO-1 expression increased significantly further in the initial low HO-1 expression group, but not in the high HO-1 group. Postoperatively, serum transaminases were significantly lower and the bile salt secretion was higher in the initial low HO-1 group, compared to the high expression group. Immunofluorescence staining identified Kupffer cells as the main localization of HO-1. In conclusion, human livers with initial low HO-1 expression (<3.4 times controls) are able to induce HO-1 further during reperfusion and are associated with less injury and better function than initial high HO-1 expression (>3.4 times controls). These data suggest that an increase in HO-1 during transplantation is more protective than high HO-1 expression before transplantation.
- Published
- 2005
- Full Text
- View/download PDF
9. In vitro maturation and fertilization of oocytes recovered from free-ranging Burchell's zebra (Equus burchelli) and Hartmann's zebra (Equus zebra hartmannae).
- Author
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Meintjes M, Bezuidenhout C, Bartels P, Visser DS, Meintjes J, Loskutoff NM, Fourie FL, Barry DM, and Godke RA
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- Animals, Cattle, Coculture Techniques methods, Coculture Techniques veterinary, Embryonic and Fetal Development physiology, Fallopian Tubes cytology, Fallopian Tubes physiology, Female, Fertilization in Vitro methods, Male, Oocyte Donation methods, Oocytes cytology, Oocytes diagnostic imaging, Pregnancy, South Africa, Ultrasonography, Equidae physiology, Fertilization in Vitro veterinary, Oocyte Donation veterinary, Oocytes physiology, Pregnancy, Animal physiology, Sperm-Ovum Interactions physiology
- Abstract
A noninvasive repeatable method to harvest oocytes for in vitro fertilization (IVF) could potentially be used to assist reproduction in endangered equid species. The objectives of this study were to evaluate a specific transvaginal ultrasound-guided oocyte recovery procedure for use in zebra mares and the general applicability of IVF procedures in zebra. Ovaries were collected from Burchell's zebra (Equus burchelli) and Hartmann's zebra (Equus zebra hartmannae) mares at routine culling for Expt. I. Of the 144 oocytes recovered from these ovaries, 70% were of excellent quality. No significant difference in oocyte quality was found between the two zebra species. Zona drilling was performed on in vitro-matured oocytes prior to IVF. Epididymal sperm from culled Burchell's zebra stallions were used for IVF. The sperm either were exposed to calcium ionophore or were not treated and served as a control. In vitro fertilized oocytes were then co-cultured with zebra granulosa cells (ZGC) or with bovine oviduct cells (BOC) for up to 8 days. Overall, a 38% cleavage rate was obtained with 16% of sperm-exposed oocytes developing to the morula or blastocyst stage. All of the embryos that developed to at least the morula stage were cultured on BOC; whereas, none of those cultured on ZGC reached the morula stage during the same interval. Cleavage rates of oocytes inseminated with ionophore-treated or with control sperm were not significantly different, suggesting that ionophore treatment of epididymal sperm for IVF in these zebra species may be redundant. In Expt. II, 10 transvaginal ultrasound-guided oocyte aspiration procedures on five captive Burchell's zebra mares recovered a total of 33 oocytes (6.6 oocytes/female) of which 94% were considered viable. This approach may be an attractive means of producing gametes for assisted reproduction in endangered species. Furthermore, results from this study indicate that IVF may become a means of producing offspring from zebra and other equid species in the future.
- Published
- 1997
10. The applicability of the cumulative embryo score system for embryo selection and quality control in an in-vitro fertilization/embryo transfer programme.
- Author
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Visser DS and Fourie FR
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- Female, Humans, Incidence, Predictive Value of Tests, Pregnancy, Pregnancy Outcome, Pregnancy, Multiple physiology, Quality Control, Retrospective Studies, Culture Techniques standards, Embryo Transfer, Embryo, Mammalian, Fertilization in Vitro
- Abstract
The cumulative embryo score system involves three aspects of relevance in pregnancy achievement during in-vitro fertilization (IVF) and embryo transfer: cleavage rates, morphological qualities and the number of embryos transferred. The scores of 602 IVF/embryo transfer trials were calculated and analysed to determine the system's relationship to pregnancy rate, pregnancy outcome and the incidence of twin and triplet pregnancies. The system was also applied to cycles where endotoxins were either present in or absent from culture medium, in order to evaluate its validity in quality control analyses. Pregnancy rates were found to increase from 4%, with scores between 1 and 10, to 35% in the 41-50 group. The score of 20 was the criterion for separating patients into poor and good pregnancy prognosis groups (P = 0.00001). Biochemical abortions occurred more frequently with scores < 20 (P = 0.00978), but a similar relationship was not found in clinical abortion rates (P = 0.62206). Birth rates below and above a score of 20 (2.8 and 19.2%, respectively) differed significantly (P = 0.0005). The scores of twins overlapped extensively with those of singleton births, but those of all triplets were > 40. The system did not reflect a correlation between embryo quality and the presence of endotoxins in culture medium.
- Published
- 1993
- Full Text
- View/download PDF
11. Multiple attempts at embryo transfer: effect on pregnancy outcome in an in vitro fertilization and embryo transfer program.
- Author
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Visser DS, Fourie FL, and Kruger HF
- Subjects
- Blood, Catheterization, Cervix Mucus, Cervix Uteri, Dilatation, Female, Humans, Incidence, Pregnancy, Pregnancy Outcome, Time Factors, Embryo Transfer methods, Fertilization in Vitro
- Abstract
Purpose: This study derives from the observation that a correlation exists between failed first attempts (FFA) at embryo transfer caused by one or more embryos remaining in the catheter and reduced pregnancy rates (20.3 vs 3.0%). The aim of this study was to examine the relationship between failed first attempts at transfer and contamination of the transfer set; the related aspects of cervix dilatation and late embryo transfer were also investigated., Results: The following observations were made. Retention of embryos in the transfer sets significantly reduced the pregnancy rate (P = 0.015); catheters contaminated with blood and cervical mucus indirectly contributed to this effect by increasing the incidence of failed first transfer attempts. Even though cervical dilatations, if indicated by uterus sounding, were done 2 days before embryo transfer, no pregnancies were effected in these 18 cases (P = 0.0001). Late transfers of embryos, due to delayed fertilization or slow cleavage rates, yielded a pregnancy rate of 10.5%., Conclusion: The approach of immediately retransferring retained embryos does not solve the problem of reduced pregnancy rates in FFA cases. It is suggested that ET should be repeated 1 day later in FFA cases in an attempt to improve pregnancy rates.
- Published
- 1993
- Full Text
- View/download PDF
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