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M Carretier

Publications and source records attributed to M Carretier.

At least 19 recordsLinked to original sources
PubMed2003

[Laparoscopic preperitoneal hernia repair].

The authors describe a technique of totally preperitoneal videoscopic inguinal hernia repair. This method allows, by cleavages, to obtain a preperitoneal space where can be individualised anatomical structures of the inguinofemoral area: pubis, pectineal ligament of Cooper, epigastric vessels. After squelettisation of the elements of the cord by release of the hernial bag, installation of a not fixed prosthesis largely covers the hernial rings.

Digestive System Surgical Procedures↗
PubMed2002

Pigs are not a reliable experimental model in the study of the haemodynamic and respiratory effects of CO2 pneumoperitoneum.

BACKGROUND: Haemodynamic and respiratory effects of a CO2 pneumoperitoneum (intra-abdominal pressure = 12 mmHg) associated to a head-up position(15 degrees ) were studied in 20 pigs using a Swan-Ganz catheter and the Single Breath Test for CO2. The pneumoperitoneum induced a moderate rise in mean arterial pressure (+17%) (P<0.001) without any variation in heart rate, cardiac output and systemic vascular resistances. RESULTS: The following respiratory effects were observed: an increase in PaCO2 (+20%) (P<0.001), PE'CO2 (+31%) (P<0.001), expired volume of CO2 (+28%) (P<0.001), arterial to end-tidal CO2 gradient (+80%) (P<0.001) and alveolar dead space (+40%) (P<0.001) occured. Alveolar ventilation remained stable. Finally and contrary to healthy human patient, intraperitoneal CO2 insufflation in pig induced slight haemodynamic changes and major respiratory modifications. CONCLUSION: Thus, our data do not support the conclusion that the pig is a reliable experimental model for studying the pathophysiology of CO2 pneumoperitoneum-induced changes in haemodynamic and respiratory parameters, in human patients.

Animals↗
PubMed2001

Pancreatic metastasis of renal cell carcinoma: presentation, treatment and survival.

PURPOSE: The pancreas is an uncommon site of metastasis from renal cell carcinoma, comprising 2% of pancreatic tumors removed in sizable series of operations. To our knowledge the role of operative resection in the setting of metastatic malignancy to the periampullary region has not yet been defined. We reviewed the records of 6 women and 2 men who underwent pancreatic resection due to malignancy and analyzed various prognostic factors. MATERIALS AND METHODS: Between 1985 and 1995, 269 patients underwent pancreatic resection for malignancy at our hospitals, including 150 (56%) for pancreatic duct cancer, 65 (24%) for carcinoma of the ampulla, 27 (10%) for distal bile duct cancer, 19 (7%) for duodenal carcinoma and 8 (3%) for renal cell carcinoma metastasis. We reviewed the records of these latter 8 cases, and analyzed demographics, primary tumor type, disease-free interval, resection type, concomitant other organ resection, histological examination of the specimen, morbidity, adjuvant therapy and survival. RESULTS: Pancreatic metastasis of renal cell carcinoma was managed by duodenopancreatectomy in 5 patients and total pancreatectomy in 3. There were no perioperative deaths. Mean tumor size in cases of a solitary pancreatic metastasis was 4 cm. (range 1.5 to 8). In the 3 patients treated with total pancreatectomy there were 2, 5 and 3 pancreatic metastases, respectively. Pathological examination revealed negative lymph nodes in all cases. Mean survival was 48 months. At study end 6 patients were alive at 24, 26, 30, 46, 84 and 88 months, while 2 died at 13 and 70 months, respectively. CONCLUSIONS: We advocate aggressive surgical resection when possible. Surgical removal of metastatic lesions prolongs survival but radical lymph node dissection is not mandatory. We also recommend careful long-term followup of patients with a history of renal cell carcinoma.

Carcinoma, Renal Cell↗
PubMed2001

Protective effect of polyethylene glycol against prolonged cold ischemia and reperfusion injury: study in the isolated perfused rat kidney.

The purpose of this study was to evaluate an intracellular solution with polyethylene glycol (PEG, molecular weight 20,000) as an impermeant, compared with University of Wisconsin (UW) and Euro-Collins (EC) solutions, after a 48-h cold storage (CS). The normothermic isolated perfused rat kidney (IPK) technique was used to assess renal function after CS. Five groups were studied: a control group (immediately reperfused, n = 10); one that received EC (n = 16); one that received UW (n = 16); and two that each received an intracellular (IC) solution, one with PEG (ICPEG, n = 16) and one without PEG (IC, n = 16). The perfusion flow rate was significantly greater in the PEG group and correlated with less significant cellular and interstitial edema and lower renal vascular resistance than in the IC, EC, and UW groups. Glomerular filtration rate was significantly higher in the PEG group during reperfusion than in the IC, EC, and UW groups. Proximal tubular functions were more efficient with PEG: fractional sodium reabsorption and total sodium reabsorption were significantly greater during reperfusion in the PEG group than in the IC, EC, and UW groups. Of greater interest is the protective effect of PEG on lipid peroxidation, which reflects ischemia/reperfusion damage. The second major effect is the dramatic ATP restoration during reperfusion, which outlines the preservation of oxidative phosphorylation after preservation by ICPEG. These results are supported by histological studies, particularly concerning brush border and mitochondrial preservation. Our results indicate that PEG is promising for cold ischemia and reperfusion injury protection.

Adenosine Triphosphate↗
PubMed2000

Protection of autotransplanted pig kidneys from ischemia-reperfusion injury by polyethylene glycol.

BACKGROUND: Ischemia-reperfusion injury (IRI) is often responsible for graft rejection and leads to delayed graft function of cadaveric kidneys. We have shown that adding polyethylene glycol (PEG 20M) to the preservation solutions helps protect isolated perfused pig kidneys against cold ischemia and reperfusion injury. METHODS: We compared the effects of adding PEG to a simplified high-K+ perfusion solution of cold-stored kidneys to Euro-Collins or University of Wisconsin solutions on the function of reperfused autotransplanted pig kidneys. The left kidney was cold-flushed with the preservation solutions and stored for 48 hr at 4 degrees C before reimplantation. Creatinine clearance and fractional excretion of sodium were analyzed 2 days before surgery and over 7 days after transplantation. Histological sections were obtained 40 min after reperfusion and on day 7 after surgery. RESULTS: Adding PEG to the perfusate significantly reduced IRI from autotransplanted pig kidneys. Creatinine clearance was significantly higher and fractional excretion of sodium was significantly lower in pigs transplanted with kidneys cold-flushed with PEG-supplemented perfusate than in those flushed with Euro-Collins or University of Wisconsin solutions. PEG supplementation also better preserved the integrity of kidney cells and markedly reduced interstitial cell infiltrates. CONCLUSION: PEG protects against IRI and reduces early cellular inflammation. PEG may impair the recruitment and migration of leukocytes into retransplanted pig kidneys. Cold preservation of donor organs with PEG-supplemented solutions may therefore help limit IRI in human renal transplantation.

Animals↗
PubMed2000

Noninvasive monitoring of citrate, acetate, lactate, and renal medullary osmolyte excretion in urine as biomarkers of exposure to ischemic reperfusion injury.

Injury during the transplant process affects the alloantigen-dependent factors and the alloantigen-independent processes of "chronic" rejection. Consequently, the determination of reliable parameters for the assessment of ischemic damage is essential for the prediction of renal changes after ischemia/reperfusion injury. The aim of this study was to assess the ability of (1)H NMR spectroscopy to predict the early graft dysfunction in an ischemia/reperfusion model after preservation in two standard preservation solutions, Euro-Collins (EC) and University of Wisconsin (UW). The second aim was to specify the role of the UW solution in preventing renal medullary injury. Urine and plasma samples from three experimental groups were examined during 2 weeks: control group (n = 5), EC group (cold flushed and 48-h cold storage of kidney in EC and autotransplantation, n = 12), and UW group (cold flushed and 48-h cold storage of kidney in UW and autotransplantation; n = 12). We also examined these kidneys 30-40 min after implantation and on the sacrifice day. Creatinine clearance was significantly reduced in the EC group during the second week. Fractional excretion of sodium and urine N-acetyl-beta-d-glucosaminidase activity were improved but not significantly different in the preserved groups. Urinary concentrations of the alpha-class glutathione S-transferase were significantly greater in the EC group during the first week after transplantation. The most relevant resonances for evaluating renal function after transplantation determined by (1)H NMR spectroscopy were those arising from citrate, dimethylamine (DMA), lactate, and acetate in urine and trimethylamine-N-oxide (TMAO) in urine and plasma. These findings suggest that graft dysfunction is associated with damage to the renal medulla determined by TMAO release in urine and plasma associated with DMA and acetate excretion. Citrate is also a urinary marker that can discriminate kidneys with a favorable evolution. Our results suggest that (1)H NMR spectroscopy is an efficient technique for detecting ischemic damage when accurate and precise data on graft injury is required. In addition, this study outlines the specific impact of the UW solution against injury to the renal medulla.

Acetic Acid↗
PubMed2000

Influence of retrieval conditions on renal medulla injury: evaluation by proton NMR spectroscopy in an isolated perfused pig kidney model.

BACKGROUND: Delayed graft function (DGF) has remained an important complication after renal transplantation. The exact causes of DGF remain to be clarified, particularly the impact of retrieval conditions and preservation factors. In the present investigation, (1)HNMR spectroscopy of urine was assessed in order to detect the influence of retrieval condition on renal medulla damage. METHODS: The isolated perfused pig kidney (IPK) was used to assess initial renal function from multiorgan donors (MOD) or single organ donors (SOD) after in situ cold flush and 24-h cold storage (CS) preservation with two standard preservation solutions: Euro-Collins (EC) and University of Wisconsin (UW) solutions. Kidneys flushed with cold heparinized saline and immediately perfused were used as the control group. Kidneys were perfused for 90 min at 37.5 degrees C for functional evaluation. During reperfusion, renal perfusion flow rate (PF) was measured. Glomerular filtration rate (GFR), tubular reabsorption of Na(+), and lactate dehydrogenase (LDH) and N-acetyl-beta-d-glucosaminidase (NAG) excretions were determined. Ischemia-reperfusion impairment was also determined by histological techniques and (1)HNMR spectroscopy. RESULTS: PF, GFR, and tubular reabsorption of Na(+) were significantly decreased in experimental groups when compared to the control group but there was no significant difference between experimental SOD groups. GFR was significantly greater in UW-MOD than in EC-MOD and tubular reabsorption of Na(+) was significantly greater in UW-MOD than in EC-MOD after 45 min of reperfusion. The release of LDH in the effluent and the urinary excretion of NAG were not significantly different after 24-h CS in the various experimental groups. The most relevant resonances determined by (1)HNMR spectroscopy were citrate, trimethylamine-N-oxide, lactate, acetate, and amino acids. Excretion of these markers was significantly different when compared to biochemical markers. A resonance (P) detected particularly in EC-MOD after 24-h CS was identified and well correlated to renal dysfunction. Histological study showed that ultrastructural damage and mitochondrial injury were more pronounced in the EC-MOD group. CONCLUSION: These results show that retrieval condition influences renal medullary damage. NMR spectroscopy, which is a noninvasive and nondestructive technique, is more efficient in assessing renal damage than conventional histology and biochemical analysis.

Acetylglucosaminidase↗
PubMed2000

Polyethylene stent blockage: a porcine model.

BACKGROUND: Endoscopic insertion of biliary stents is a useful treatment for obstructive jaundice resulting from unresectable tumors of the pancreas and biliary tree. The main drawback is the recurrence of jaundice due to clogging. The aim of this study was to establish an experimental model of polyethylene stent clogging in large white pigs. METHODS: A straight polyethylene stent of 5F (group I), 7F (group II) or 10F size (group III) was inserted in the common bile duct. Animals were killed at 2 months, or earlier if physical signs suggesting stent clogging occurred. Chemicophysical analysis of stent deposition combined stereomicroscopy and identification of the contents by means of Fourrier transform infrared spectroscopy. Bacteriologic analyses included identification of aerobic and anaerobic bacteria and measurement of beta-glucuronidase, lecithinase and lipase activities. RESULTS: Physical signs suggesting stent obstruction or death occurred in 8 of 8 animals in group I, 11 of 12 in group II, and 2 of 8 in group III (p < 0.001). The proportion of mucoprotein in the stent contents tended to fall with increasing stent diameter (mean 82%, 58% and 47% for 5F, 7F and 10F, respectively), whereas wheat starch and calcium bilirubinate content increased with increasing stent diameter (9% and 4%, 18% and 10%, and 29% and 23% for 5F, 7 F, and 10F, respectively), although none of these differences were statistically significant. A variety of bacteria were cultured from the stent deposits, including anaerobic strains. Clostridium species were associated with the highest enzyme activities. CONCLUSIONS: In this model the major component of early stent deposits was mucoprotein, and numerous aerobic and anaerobic bacteria were isolated. Formation of calcium bilirubinate was a late phenomenon and poorly related to bacterial enzymatic activities.

Animals↗