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B Dousset

Publications and source records attributed to B Dousset.

At least 91 records · Page 5Linked to original sources

Evidence for the detrimental role of proteolysis during liver preservation in humans.

BACKGROUND/AIMS: Proteolysis may persist in the liver allograft during cold storage. The aim of this study was to determine the significance of proteolysis within liver allografts stored at 4 degrees C in University of Wisconsin preservation fluid. METHODS: Thirty recipients of 32 liver allografts were studied prospectively. Amino acid content of the preservation fluid was analyzed at the end of cold storage and was correlated to graft and patient outcome after transplantation. RESULTS: Analysis of the preservation fluid showed the presence of free amino acids, the profile of which was different from that of stored liver parenchyma. Concentrations of amino acids (alanine, cysteine, leucine, isoleucine, methionine, lysine, ornithine, and threonine) and transaminases (alanine aminotransferase and aspartate aminotransferase) in the preservation fluid correlated with the duration of cold ischemia. Indexes of graft dysfunction (serum alanine aminotransferase and aspartate aminotransferase peaks and prothrombin rate) correlated with concentrations of cysteine, alanine, isoleucine, leucine, methionine, lysine, ornithine, and threonine, whereas enzyme concentrations in the fluid were not predictive of graft dysfunction. CONCLUSIONS: These data suggest that liver proteolysis occurs during cold storage and may have a detrimental effect on the outcome after transplantation. The measurement of the amino acids in the preservation fluid at the end of the cold storage period could help to identify the most severely damaged organs.

Adenosine↗

Gastroesophageal reflux and acute life-threatening episodes: role of a central respiratory depression.

The aim of this study was to evaluate plasma levels of beta-endorphins in babies with gastroesophageal reflux (GOR) admitted for acute life-threatening episodes (ALTE). In case of ALTE (n = 15), beta-endorphin levels were significantly increased compared to sudden infant deaths syndrome siblings with GOR of a similar gravity evaluated for risk factors (n = 13). beta-Endorphin levels are decreased following successful treatment of GOR. Studies of ventilation suggest that changes in the central respiratory drive are associated with a reduction in plasma beta-endorphin levels.

Acute Disease↗

Role of the kidney in the production of a low molecular weight growth factor (MW < 1000 Da): experimental study in the pig.

Small peptide molecules known as low molecular weight growth factor (LMW-GF) have been identified in human serum. They enhance the effect of IGF-1 (insulin-like growth factor) on proteoglycan synthesis. In the present work we investigated the role played by the kidney in the production of LMW-GF, using the pig as an experimental model. Six pigs underwent bilateral nephrectomy followed 24 h later by orthotopic autotransplantation of the kidney. Renal and liver functions were evaluated by measurement of serum creatinine, urea, electrolytes, amino transferases (ASAT, ALAT), proteins, and bilirubin. LMW-GF was measured by bioassay using 11-day-old pelvic chick embryo cartilages. We observed that LMW-GF quickly disappeared from pig serum after nephrectomy and only reappeared when transplantation was successful. Reappearance of LMW-GF can precede improvement of renal function evaluated by plasma creatinine levels. These data appear to demonstrate that the kidney is involved in LMW-GF production.

Acute Kidney Injury↗

[Physiological role of PTHrP].

Parathyroid hormone related protein (PTHrP) is the aetiological factor for the syndrome of humoral hypercalcemia of malignancy. The PTHrP gene encodes three isoforms of respectively 139, 141 and 173 amino acids with N-terminal homology to parathormone (PTH). PTHrP, which has a wide tissue distribution, appears to be a polyhormone with different physiologic functions that depend on the particular fragment secreted. PTHrP may act in an autocrine, a paracrine or an endocrine fashion. There is evidence for a role in the growth and development of both embryonic and mature tissues, in cellular differentiation, in smooth muscle relaxation, lactation and calcium and magnesium transport. The best known PTHrP functions are those mediated by the N-terminal domain fixation on the classical PTH/PTHrP receptor. Nevertheless, several other functions are mediated by different fragments of PTHrP such as midregion fragments or carboxy-terminal forms. Each of these functional forms of PTHrP has one or several physiological function(s) which is (are) mediated by his own specific receptors and signal transduction pathways, some of which may be tissue specific.

Animals↗

[Surgical treatment of severe ulcerous hemorrhages: predictive factors of operative mortality].

OBJECTIVES: Multivariate analysis of operative mortality in patients with bleeding peptic ulcer. METHODS: Seventy-eight consecutive patients, who underwent emergency surgical treatment for bleeding peptic ulcer were reviewed retrospectively. There were 49 males and 29 females, with a mean age of 64.3 years, 2/3 of whom had associated medical disease. Surgical treatment was conservative in 63 cases: oversewing or ulcer excision, alone (n = 29) or associated with vagotomy (n = 34); and was radical in 15 cases: antrectomy+vagotomy (n = 10) or partial gastric resection (n = 5). RESULTS: There were 17 (21.8%) postoperative deaths and 19 (24.3%) bleeding recurrences. The causes of death included 9 bleeding recurrences, 7 organ failures and one duodenal leakage. On multivariate analysis, previous medical illness (cirrhosis or cardiac insufficiency (P < 0.001), shock at admission (P < 0.001), prolonged delay until surgery (P < 0.001), and bleeding recurrence (P < 0.001) were independently associated with increased mortality. In contrast, the type of surgical procedure did not influence postoperative mortality, whereas bleeding recurrence was more frequent in case of conservative surgery (P < 0.03) and anticoagulation therapy (P < 0.01). CONCLUSION: These results suggest that surgical treatment of bleeding peptic ulcer should be proposed early in high-risk patients. A radical procedure should be favoured since it reduces bleeding recurrence rate without increasing operative mortality.

Adult↗

[Laparoscopic splenectomy. The "hanging spleen technique" in a series of nineteen cases].

We have used an new patient position for laparoscopic splenectomy: the patient is placed in the right lateral supine position on a "bean bag" positioning apparatus and the left arm is elevated. The operator stands to the patient's right, the first assistant is on the patient's right and the second is on the patient's left. This position provides very good exposure of the spleen, which hangs from the diaphragm by the peritoneal attachments and the inferior pole splenic vessels, short gastric vessels and splenic hilus vessels can be released successively. We have now performed 19 splenectomies using the "Hanging Spleen Technique" with three conversions to open surgery. Splenectomy was always possible with the use of a plastic bag through the 12 mm trocar hole in 12 cases and through this enlarged hole in 2 cases. The mean post-operative stay was 4.3 days and the mean time to return to work was 19 days. Laparoscopic splenectomy is a feasible and safe procedure with this patient position. Obesity and splenomegaly are no longer absolute contra-indications.

Acetaminophen↗

[Liver transplantation in children].

Liver transplantation has become the treatment of many chronic liver diseases, acute hepatic failure and several metabolic diseases in children. Early referral to a transplantation center represents the major condition for its favourable outcome, in order to undertake this complex surgical procedure under the best conditions and to allow a rapid and complete recovery. The increasing shortage of organs leading to graft reduction, graft splitting and living related donation, the feasibility of multiple organ transplantation, the progress of gene therapy, the development of new extra-corporeal liver assist devices and the introduction of the auxiliary partial orthotopic liver transplantation have all contributed to significative changes in the perspectives of pediatric liver transplantation. Furthermore, new immunosuppressors as well as encouraging experimental results on graft tolerance may help in the near future to improve the long-term quality of life of pediatric recipients.

Child↗

Insulin utilization and kinetic effect on hybridoma metabolism in batch and continuous cultures.

This paper discusses the insulin utilization kinetics and the effect of its concentration during batch and continuous mass cultures of the murine VO208 hybridoma cells, using a home-made serum-free medium. Our results show that insulin is utilized by the cells, with a specific rate of 1 relative units (RU) per 10(9) cells per h in batch culture. In continuous reactor running at different insulin levels, this consumption rate is observed to vary from 0.13 to 0.55 RU per 10(9) cells per h when the insulin activity increases from 0.3 to 35 RU l-1 and then to stabilize for higher insulin levels until 110 RU l-1. A low insulin amount in the medium around 0.01 RU l-1, which is near physiological levels, is found sufficient to promote the cell growth. Interestingly, we observe that too high insulin levels, above 25 RU l-1, induce a reduction of the cell density due to an inhibitory effect on the maximal specific cell growth rate. Furthermore, the specific rate of MAb production is found to be independent of the insulin amount in the medium.

Animals↗

The influence of cold ischemia time on biliary complications following liver transplantation.

Biliary complications are a continuing source of morbidity and mortality following orthotopic liver transplantation. The results of 100 whole-liver allografts performed in 92 adult patients were reviewed to determine whether cold ischemia time and preservation injury influenced both the incidence and type of biliary complications. Mean cold ischemia time was 10.2 +/- 0.5 h (range 3.6-19). Eighteen patients (19.6%) developed 25 biliary complications: there were eight anastomotic leaks, eight anastomotic strictures, six non-anastomotic strictures, two cystic duct mucoceles, and one biliary fistula following T-tube removal. Despite the high rate of reoperative surgery (68%), no death was attributable to biliary complications. Neither cold ischemia time nor early graft function influenced the rate of biliary complications or strictures of either type. Furthermore, an analysis of different factors revealed no predisposing effect of the pre-operative status of the recipient, type of biliary reconstruction, blood requirement, vascular complications, rejection or cytomegalovirus infection on the incidence of biliary complications or strictures. Only chronic rejection could be singled out as a risk factor for non-anastomotic strictures (p = 0.05). These results suggest that prolonged cold ischemia time does not seem to affect the rate or type of biliary complications following orthotopic liver transplantation. In view of these data, there is no clear reason to reconsider prolonged cold ischemia up to 15 h in University of Wisconsin solution, as it has transformed liver transplantation from an emergency operation to a semi-elective procedure and allows longer back-table preparation for graft reduction of splitting.

Adolescent↗

Serum lipids and apolipoproteins in liver transplant recipients: a comparative study of cyclosporin A and FK 506.

The immunosuppressive agent cyclosporin A (CsA) is reportedly associated with clinically adverse effects on circulating lipid and apolipoprotein concentrations. To date few data have been reported concerning the effects on lipid metabolism of the new macrolide immunosuppressive agent FK 506, and no comparative studies of the effects of these drugs have been performed. In consideration of the pivotal role of the liver in lipid metabolism, we measured fasting serum lipids and apolipoproteins a median of 8 (range 5 to 9) months after the operation in 20 clinically stable liver transplant recipients randomly allocated to maintenance immunosuppression with CsA +/- azathioprine (n = 10) or FK 506 (n = 10). To avoid the confounding effects of corticosteroids on lipid metabolism, prednisolone was withdrawn at least 6 weeks beforehand in each case. Ten healthy volunteers matched for age and body mass index served as control subjects. Serum total cholesterol concentration was significantly lower in both the CsA (p < 0.001) and FK 506 (p < 0.05) treatment groups when compared with the healthy control subjects. Serum high-density lipoprotein (HDL) cholesterol concentration was also significantly lower in both the CsA (p < 0.005) and FK 506 (p < 0.01) treatment groups. Neither the ratio of serum total cholesterol to HDL cholesterol nor the fasting triglyceride concentrations were significantly different (p > 0.1) from those of the healthy control subjects for either transplant group. Serum apolipoprotein B level was lower than that of the control group in both the CsA (p < 0.005) and FK 506 groups (p = 0.06).(ABSTRACT TRUNCATED AT 250 WORDS)

Apolipoproteins↗