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A Charlier

Publications and source records attributed to A Charlier.

12 recordsLinked to original sources

[Pseudohepatoma].

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Carcinoma, Hepatocellular↗

Release of mifepristone from biodegradable matrices: experimental and theoretical evaluations.

Diffusion of mifepristone in poly [(D,L) lactide-co-glycolide)] films was studied by release experiments. Five 50/50 copolymers of increasing molecular weights were used. The degradation effects were shown by gel permeation chromatography (GPC). Release kinetics show the effect of copolymer molecular weights on diffusion and degradation properties of loaded films. A new theoretical model for drug release from a biodegradable matrix was proposed with two assumptions: correlation of the diffusion coefficient with the polymer molecular weight and existence of a first order degradation kinetic. Higuchi's equation is verified at early time and the diffusion coefficient in the non-degraded polymer can be measured. The degradation constant is determined at long time and is compared with the results of GPC.

Algorithms↗

Comparison of two methods for the measurement of rat liver methylmalonyl-coenzyme A mutase activity: HPLC and radioisotopic assays.

Methylmalonyl-coenzyme A mutase (MCM) is a 5'-deoxyadenosylcobalamin-linked mitochondrial enzyme that catalyzes the isomerization of L-methylmalonyl-coenzyme A to succinyl-coenzyme A. In vitro assays of total and holo-MCM activities are important tools for investigating the cobalamin pathway. Several methods have been described for measuring MCM activity. The most commonly-used method is a radioassay based on the permanganate oxidation of DL[CH(3)-(14)C]methylmalonyl-coenzyme A, but radiometric methods are insensitive, laborious, and time-consuming. Therefore, we have compared this method with a nonradiometric assay, potentially most sensitive, based on the separation of methylmalonyl-coenzyme A and succinyl-coenzyme A by high performance liquid chromatography (HPLC). We determined the optimal assay conditions and the reproducibility and sensitivity of each technique. The results obtained by the two techniques were very different: the specific activities obtained by the permanganate oxidation method (0.039 +/- 0.013 nmol/min/mg protein for the holo-MCM activity and 1.90 +/- 0.69 nmol/min/mg protein for the total-MCM activity) were threefold lower than those obtained with the HPLC method (0.124 +/- 0.011 nmol/min/mg protein for the holo-MCM activity and 6.15 +/- 0.76 nmol/min/mg protein for the total-MCM activity). The coefficients of variation for the radiometric method (18.4-40.6%) were three to five times greater than those for the HPLC assay (3.5-12.2%). This demonstrates the lack of sensibility and reproducibility of the permanganate radioassay. Thus, the radiometric method is not suitable for measuring low mutase activities such as the holo activities in tissues. The intrinsic inconvenience of the radiometric assay indicates that the HPLC method is a method of choice for measuring MCM activity.

Journal Article↗

Diagnosis of asymptomatic common bile duct stones: preoperative endoscopic ultrasonography versus intraoperative cholangiography--a multicenter, prospective controlled study. French Associations for Surgical Research.

BACKGROUND: In patients with symptomatic cholelithiasis, preoperative diagnosis of common bile duct (CBD) stones can modify the therapeutic strategy. The aims of this prospective, controlled multicenter study were to assess the feasibility, concordance, discordance, and indexes such as sensitivity, specificity, positive and negative predictive values, and accuracy of preoperative endoscopic ultrasonography compared with those of intraoperative cholangiography (IOC) in the diagnosis of asymptomatic CBD stones (i.e., patients undergoing cholecystectomy with no clinical or biologic evidence of CBD stones). METHODS: From October 1993 to October 1995, 240 consecutive patients with symptomatic cholelithiasis, scheduled for cholecystectomy in 14 surgical centers, were enrolled in this study. All patients were selected for this study according to a preoperative high-risk CBD stone predictive score. Each patient underwent both endoscopic ultrasonography and IOC, as well as surgical exploration of the CBD when stones were detected during one or both preoperative investigations. All patients were seen 1 months and 1 year after operation to check for residual stones. RESULTS: The feasibility of endoscopic ultrasonography was significantly higher overall than that of IOC (99% vs 90%; p < 0.001), except when IOC was through a laparotomy (97% vs 93%; p = 0.16). The number of patients available for study was 215. In 198 cases (92%), results of both investigations were in concordance (161 negative and 37 positive values). Seventeen cases (8%) were discordant. There was overall concordance between the two investigations (kappa coefficient 0.764; 95% confidence interval 0.66 to 0.87), but the percentage of discordance was in favor of IOC. Sensitivity and specificity of IOC were significantly higher than those of endoscopic ultrasonography (1.00 and 0.98 vs 0.85 and 0.93, respectively). With a prevalence of CBD stones of 19%, positive and negative predictive values of IOC were significantly higher than those of endoscopic ultrasonography (0.93 and 1.00 vs 0.75 and 0.96, respectively). CONCLUSIONS: Although endoscopic ultrasonography is feasible more often than IOC, IOC is associated with a slightly lower degree of discordance and better information indexes and remains an efficient method of investigation for CBD stones. Endoscopic ultrasonography can be suggested in preference to endoscopic retrograde cholangiography when postoperative residual stones are suspected but need not be performed routinely before cholecystectomy.

Adult↗

Preoperative evaluation of the probability of common bile duct stones. French Association for Surgical Research.

BACKGROUND: This study was done to determine if certain criteria could predict the presence of common bile duct stones in patients with symptomatic gallstones. It was hoped that patients could be identified in whom intraoperative cholangiography was unnecessary. STUDY DESIGN: One hundred seventy-five patients, from 15 surgical centers, were prospectively enrolled. For each patient, the preoperative score (Huguier score) previously published was calculated according to clinical and ultrasound data: age, diameter of the common bile duct, diameter of the smallest gallstone, history of biliary colic, and acute cholecystitis. All patients underwent an open cholecystectomy and an intraoperative cholangiography. The absence or presence of a common bile duct stone was evaluated during the operation, if necessary, after an instrumental investigation of the common bile duct. RESULTS: Ultrasound was not interpretable in eight (5 percent) of 175 patients. Final analysis was made from the charts of the 167 remaining patients. Thirty (18 percent) had common bile duct stones. When the score was equal to or greater than 3.5, the risk of having a common bile duct stone was 24 percent (27 of 111). When the score was less than 3.5, this risk was 5 percent (three of 56). CONCLUSIONS: Huguier's score is well assessed and can be safely used. Intraoperative cholangiography could be avoided in 33 percent of patients when the score is less than 3.5 (56 of 167).

Age Factors↗

Alterations in endocardial vascular resistance after reperfusion in a low flow, high demand model of ischemia: effects of dipyridamole and WEB-2086, a platelet-activating factor antagonist.

To determine if alterations in regional coronary vascular resistance could occur in the type of myocardial ischemia present in severe angina pectoris, regional perfusion and function were studied in 35 conscious sedated dogs. A stenosis producing severe hypokinesia of the perfused segment was created for 2 h on the left anterior descending coronary artery and 10 episodes of 1 min of high demand ischemia (atrial pacing at a rate sufficient to induce dyskinesia in the hypoperfused segment) were superimposed before reperfusion. The dogs were randomized into three treatment groups: control (n = 13), dipyridamole (n = 10) or WEB-2086 (n = 12), an antagonist of the effects of the endogenous platelet-activating factor. During stenosis, residual endocardial blood flow in the ischemic but nonnecrotic area averaged 0.72 +/- 0.14, 0.38 +/- 0.13 and 0.68 +/- 0.17 ml/min per g in the control, WEB-2086 and dipyridamole groups, respectively. Twenty-four hours after reperfusion, endocardial blood flow in the ischemic area was significantly lower in control dogs (1.04 +/- 0.15 ml/min per g) than in dogs treated with WEB-2086 (1.44 +/- 0.28 ml/min per g; p less than 0.03) or dipyridamole (3.00 +/- 0.83 ml/min per g; p less than 0.01). Accordingly, in control dogs, endocardial coronary vascular resistance in the ischemic area was increased after reperfusion from 85 +/- 11 to 124 +/- 27 mm Hg/(ml/min per g) (p less than 0.05) after 24 h. In contrast, coronary vascular resistance in the ischemic area remained unchanged in dogs receiving WEB-2086 (77 +/- 8 to 79 +/- 9 mm Hg/(ml/min per g); p = NS) and it decreased significantly in dogs receiving dipyridamole (72 +/- 8 to 44 +/- 8 mm Hg/(ml/min per g); p less than 0.01). Regional function after 24 h remained depressed in all three groups. These data indicate that low flow, high demand ischemia induces alterations in the subendocardial microvasculature. Such alterations in regional coronary vascular resistance might play a role in several forms of ischemic heart disease such as in severe angina, but they appear susceptible to improvement by therapeutic interventions that influence granulocyte and platelet activation.

Adenosine↗

Assessment of thallium-201 redistribution versus glucose uptake as predictors of viability after coronary occlusion and reperfusion.

Both 201Tl redistribution and persistent glucose uptake have been proposed as markers of viability after reperfusion. In the present study, they have been compared in the same open-chest canine preparation of occlusion and reperfusion. Ten fasting dogs were subjected to 2 hr of left anterior descending coronary artery occlusion and 4 hr of reperfusion. Myocardial blood flow was determined by a microsphere technique 100 min after occlusion and 3 hr after reperfusion. 201Tl was injected intravenously 20 min before reperfusion. Serial biopsy samples were obtained from ischemic and normal areas. 18F-2-deoxyglucose, a tracer of exogenous glucose uptake, was injected 3 hr after reperfusion. Thirty minutes before the animals were killed, simultaneous blood samples were taken from the femoral artery and the regional coronary veins draining the reperfused and the remote areas. Dogs were killed 4 hr after reperfusion was established. Area at risk was assessed by dye injection in vivo and area of necrosis by triphenyl tetrazolium chloride (TTC) staining, with confirmation by electron microscopy. Immediately after death, endocardial and epicardial samples were taken from regions characterized as risk regions, areas of necrosis, areas of patchy necrosis, and normal areas. These samples were counted in a scintillation well counter. Four hours after reperfusion, in ischemic myocardium (TTC positive) the relative 201Tl gradient between ischemic and normal regions was 26 +/- 13%, whereas in necrotic samples, this gradient was 71 +/- 26%.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

[A large aneurysm of the inferior mesenteric artery. Apropos of a case. Review of the literature].

The prevalence of inferior mesenteric aneurysms is difficult to evaluate in the literature, only four cases having been published up to the present. The case described here was a large aneurysm of the inferior mesenteric artery measuring 10 cm by 8 cm of atheromatous origin, discovered echotomographic investigation of an abdominal mass and confirmed by aortography. Operation consisted in endoaneurysmorrhaphy with reimplantation of the main branch supplying the sigmoid arteries into the aorta combined with reimplantation of the right common iliac eroded by the aneurysm into the right side of the aorta. This type of lesion raises two problems: diagnostic: echotomography and digitalised angiography will certainly facilitate the detection of such lesions, the risk of rupture of which is considerable; therapeutic: distal reimplantation of the inferior mesenteric artery which is decided on the basis of its anatomical state and above all the superior mesenteric and coeliac collateral circulation in order to avoid any risk of ischaemia of the descending colon.

Aneurysm↗

[Gastrectomy with "primary" gastro-jejunal anastomosis. A new way of using mechanical suture instruments (author's transl)].

A new way of performing Billroth II-type gastrectomy using mechanical suture instruments is described. After section and closure of the duodenum with a TA 55 stapler,, the stomach is exteriorized and the jejunal loop is brought into contact with its posterior surface. A GIA stapler is introduced into stab wounds in the stomach and jejunum, and the gastrectomy is performed. The anastomotic suture is included in the "secondary" gastric resection suture with one single application of a TA 90 stapler. This original resection technique, which ensures primary establishment of gastro-intestinal continuity, has been used on 52 occasions since 1973. There was no increase in mortality and no postoperative haemorrhage or fistula. The perfect quality of the anastomis was confirmed by control radiographic and endoscopic examinations.

Gastrectomy↗

[Severe digestive manifestations of rheumatoid purpura in adults].

The authors report three cases of Scholein-Henoch's purpura in adults which were characterized by atypical severity of the digestive signs which led to laparotomy. In one case, the digestive signs preceded the onset of the cutaneous purpura, which made the diagnosis difficult. The digestive impact was confirmed endoscopically (petechia, ulceration, ulcerated stenosis) in two of the three patients. Damage of the small intestine predominated, as in the literature, but only one patient required resection of the intestine. These observations highlight the importance of endoscopic exploration in cases of abdominal signs combined with Scholein-Henoch's purpura in adults. They also demonstrate the difficulty of evaluating the prognosis and treatment in severe, peritoneo-occlusive forms.

Adult↗