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Eric Goffin

Publications and source records attributed to Eric Goffin.

35 records · Page 2Linked to original sources
PubMed2002

Tacrolimus and low-dose steroid immunosuppression preserves bone mass after renal transplantation.

Bone loss, a recognized complication of renal transplantation (TP), is mainly attributed to steroids. The effect of other immunosuppressive agents on patients' bone mass is difficult to distinguish from that of steroids. In this study, we evaluate the evolution of bone mass density over the first 12 months following renal TP in two groups of patients given either low-dose steroids with tacrolimus ( n=7) or normal-dose steroids and cyclosporine ( n=19). Bone mineral density (BMD) of the lumbar spine, total hip, and hip subregions and total-body bone mineral content (BMC) were measured by dual-energy X-ray absorptiometry within the first 15 days, and 1 year after TP. Biological markers of bone turnover (serum calcium, phosphate, total alkaline phosphatase activity, intact parathyroid hormone, bone-specific alkaline phosphatase, calcitriol, and urinary pyridinolines) were regularly measured during follow-up. After TP, renal function improved rapidly in all patients. One year after TP, bone mass had decreased significantly in the cyclosporine group in all investigated sites. By contrast it had increased in the tacrolimus group. In order to compare the evolution of bone mass in patients given similar amounts of steroids, the cyclosporine group was subdivided in tertiles according to the 1-year cumulative oral intake of prednisolone. A significant bone loss was still observed in the low-steroid cyclosporine subgroup but not in the tacrolimus group, despite the similar steroids intake (3.5+/-0.5 g and 2.7+/-1 g, respectively). Bone gain in the tacrolimus group occurred despite a previous longer dialysis duration and a higher number of postmenopausal women who were not receiving hormone substitutes. Long-term evaluation of bone density (3-5 years post-TP) confirmed the bone gain in the tacrolimus patients. Interestingly, the profile of the biological markers of bone turnover appeared better in patients prescribed tacrolimus than in those given cyclosporine, though the differences did not reach statistical significance. Weconclude that tacrolimus associated with low-dose steroids might better preserve bone mass after renal TP than cyclosporine and normal doses of steroids.

Absorptiometry, Photon↗
PubMed2002

Intrafamilial phenotype variability in nephrogenic diabetes insipidus.

X-Linked nephrogenic diabetes insipidus (NDI), which accounts for 90% of inherited cases of NDI, is caused by mutations in the AVPR2 gene that encodes the arginine vasopressin (AVP) receptor type 2 (V2R). The V2R mediates the antidiuretic action of AVP in principal cells of the collecting duct. To date, only three AVPR2 mutations (P322S, D85N, and G201D) have been associated with a mild NDI phenotype, and intrafamilial phenotype variability has not been reported in affected males. We describe a novel Belgian family with X-linked NDI caused by substitution of a histidine for an arginine at position 137 (R137H) of AVPR2. This mutation has been identified in two brothers and their mother. The R137H mutation results in a failure of V2R to stimulate adenylate cyclase and has been associated consistently with severe NDI and the inability to increase urinary osmolality to greater than plasma osmolality during water deprivation and/or infusion of 1-desamino-8-d-arginine vasopressin. Detailed examination of the two affected brothers showed the typical NDI phenotype in the 45-year-old proband, whereas a milder clinical phenotype associated with significant urinary concentrating ability during water deprivation was documented in the 33-year-old brother. Thus, in this family, the R137H mutation is associated with either a mild or severe NDI phenotype. Mechanisms that might account for these findings include genetic and/or environmental modifiers.

Amino Acid Sequence↗
PubMed2002

Enteric hyperoxaluria: a hidden cause of early renal graft failure in two successive transplants: spontaneous late graft recovery.

A 37-year-old patient underwent two successive renal transplantations 7 months apart. He remained dialysis dependent. Early biopsy of both grafts revealed widespread calcium oxalate deposition suggestive of acute oxalate nephropathy. Several causes of oxalate nephropathy, including primary oxalosis and an increased intake of oxalic acid precursors, were excluded. Two years later, the identification of steatorrhea with radiologic signs of chronic pancreatitis led to the hypothesis of enteric hyperoxaluria. Surprisingly, 11 months after the second transplantation, graft function improved progressively allowing interruption of dialysis. Three years later, renal function is stable. The causes and prevention of acute oxalate-induced graft failure are highlighted. Subclinical evidence of enteric hyperoxaluria should be looked for and appropriate therapy instituted as early as possible. The possibility of a late recovery of renal function warrants attentive patience from attending physicians.

Acute Kidney Injury↗
PubMed2002

In vitro antiplasmodial activity of Tithonia diversifolia and identification of its main active constituent: tagitinin C.

The antimalarial properties of Tithonia diversifolia, an Asteraceae traditionally used to treat malaria, were investigated in vitro against three strains of Plasmodium falciparum. The ether extract from aerial parts of the plant collected in São Tomé e Príncipe, demonstrated good antiplasmodial activity (IC 50 on FCA strain: 0.75 microg/ml). A bioassay guided fractionation of this extract led to the isolation of the known sesquiterpene lactone tagitinin C as an active component against Plasmodium (IC 50 on FCA strain: 0.33 microg/ml), but also possessing cytotoxic properties (IC 50 on HTC-116 cells: 0.706 microg/ml).

Animals↗
PubMed2000

Vascular proliferation and enhanced expression of endothelial nitric oxide synthase in human peritoneum exposed to long-term peritoneal dialysis.

Long-term peritoneal dialysis (PD) is associated with alterations in peritoneal permeability and loss of ultrafiltration. These changes originate from increased peritoneal surface area, but the morphologic and molecular mechanisms involved remain unknown. The hypothesis that modifications of activity and/or expression of nitric oxide synthase (NOS) isozymes might play a role in these modifications, via enhanced local production of nitric oxide, was tested in this study. NOS activities were measured by the L-citrulline assay in peritoneal biopsies from seven control subjects, eight uremic patients immediately before the onset of PD, and 13 uremic patients on short-term (<18 mo, n = 6) or long-term(>18 mo, n = 7) PD. Peritoneal NOS activity is increased fivefold in long-term PD patients compared with control subjects. In uremic patients, NOS activity is positively correlated with the duration of PD. Increased NOS activity is mediated solely by Ca(2+)-dependent NOS and, as shown by immunoblotting, an upregulation of endothelial NOS. The biologic relevance of increased NOS in long-term PD was demonstrated by enhanced nitrotyrosine immunoreactivity and a significant increase in vascular density and endothelial area in the peritoneum. Immunoblotting and immunostaining studies demonstrated an upregulation of vascular endothelial growth factor (VEGF) mostly along the endothelium lining peritoneal blood vessels in long-term PD patients. In the latter, VEGF colocalized with the advanced glycation end product pentosidine deposits. These data provide a morphologic (angiogenesis and increased endothelial area) and molecular (enhanced NOS activity and endothelial NOS upregulation) basis for explaining the permeability changes observed in long-term PD. They also support the implication of local advanced glycation end product deposits and liberation of VEGF in that process.

Adult↗
PubMedDate not supplied

Quantification of tagitinin C in Tithonia diversifolia by reversed-phase high-performance liquid chromatography.

A simple, rapid and reliable reversed-phase high-performance liquid chromatographic method for the determination of tagitinin C, an anti-plasmodial sesquiterpene lactone isolated from the aerial parts of Tithonia diversifolia, has been developed. The assay has been used to quantify tagitinin C in various extracts of the aerial parts of T. diversifolia.

Antimalarials↗
PubMedDate not supplied

Vancomycin and ciprofloxacin: systemic antibiotic administration for peritoneal dialysis-associated peritonitis.

OBJECTIVES: Peritonitis due to peritoneal dialysis (PD) is best treated empirically while waiting for the results of the dialysate culture. Thus, antibiotic therapy must cover both gram-positive and gram-negative micro-organisms. First, over a period of 9 years in a multicenter study we evaluated the efficiency of a vancomycin and ciprofloxacin combination given as the first-line treatment protocol for PD peritonitis. Second, we evaluated whether a systemic route of administration of the antibiotics could be an interesting alternative to the usual cumbersome intraperitoneal drug administration. METHODS: Vancomycin 15 mg/kg body weight, intravenous, and oral ciprofloxacin 250 mg two times per day (500 mg twice per day if residual creatinine clearance was above 3 mL/minute) were prescribed at diagnosis of peritonitis. Vancomycin injections were repeated (when blood trough level was expected to be below 12 microg/mL) in cases of gram-positive organisms for a total duration of 3 weeks. Ciprofloxacin was given for a total of 3 weeks in cases of gram-negative and a total of 10 days for susceptible gram-positive infections. RESULTS: A total of 129 episodes of peritonitis occurred; 28 of them were not included in the study because of protocol violation (n = 15) or fungal (n = 7) or fecal (n = 6) peritonitis, leaving 101 peritonitis episodes for analysis. 52 (51.5%) gram-positive and 28 (27.7%) gram-negative organisms were grown; 38 gram-positive organisms were coagulase-negative staphylococci. No organism was identified in 8 peritonitis episodes, whereas 13 peritonitis episodes were caused by more than 1 organism. 35% of the coagulase-negative staphylococci were resistant to first-generation cephalosporin and methicillin, whereas all were susceptible to vancomycin. For gram-negative bacilli, the susceptibility rate was 96% and 95% for ciprofloxacin and ceftazidime respectively. The overall treatment success rate was 77.2% (78 of the 101 peritonitis episodes): 61.4% at first intention and 15.8% after optimization of the antibiotic therapy (second intention). The protocol failed in 22.8% of the peritonitis episodes. Hospitalization was required in 52% of the peritonitis episodes; average hospitalization was 11 (range 1-45) days. CONCLUSION: Systemic vancomycin and ciprofloxacin administration is a simple and efficient first-line protocol antibiotic therapy for PD peritonitis. In our opinion, vancomycin should still be used for gram-positive infections because of its high susceptibility rate compared with first-generation cephalosporins, providing a close monitoring of the local epidemiology. Oral ciprofloxacin provides satisfactory results in gram-negative infections, comparable to those obtained with intraperitoneal ceftazidime or aminoglycosides.

Administration, Oral↗