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B Rousseau

Publications and source records attributed to B Rousseau.

At least 19 recordsLinked to original sources
PubMed1989

Transverse and lateral distribution of phospholipids and glycolipids in the membrane of the bacterium Micrococcus luteus.

The photodimerization of anthracene was used to investigate the transverse and lateral distribution of lipids in the membrane of the Gram-positive bacterium Micrococcus luteus. 9-(2-Anthryl)nonanoic acid (9-AN) is incorporated at a high rate into various membrane lipids of M. luteus. On irradiation of intact bacteria at 360 nm, anthracene-labeled lipids form stable photodimers which can be extracted and separated by thin-layer chromatography. We present here the results of a study on the distribution of two major lipids, phosphatidylglycerol (PG) and dimannosyldiacylglycerol (DMDG), within each leaflet of the membrane lipid bilayer. After metabolic incorporation of a tritiated derivative of 9-AN in M. luteus, the radioactivity associated with the photodimers issued from PG and DMDG was counted. In the bacterial membrane, the ratio of PG-DMDG heterodimer with respect to PG-PG and DMDG-DMDG homodimers is around half of what should be obtained for a homogeneous mixture of the two lipids. In order to find out whether this was due to an asymmetric distribution of the two lipids between the two membrane leaflets or a heterogeneous distribution of the two lipids within the same membrane leaflet, the transverse distribution of PG and DMDG was also investigated. This was carried out by following the kinetics of oxidation of the two lipids by periodic acid in the membrane of M. luteus protoplasts. PG predominated slightly in the outer layer (60%), while DMDG was found to be symmetrically distributed between the two leaflets. By itself, this lipid asymmetry cannot account for the lipid distribution determined from the photodimerization experiments. This indicates that PG and DMDG are not homogeneously distributed in the plane of the bacterial membrane.

Anthracenes↗
PubMed1989

Biochemical identification of two types of phenamil binding sites associated with amiloride-sensitive Na+ channels.

The existence of distinct forms of the epithelium Na+ channel that differ in their sensitivity to amiloride has been repeatedly suggested by physiological data. The biochemical basis for these differences was analyzed by using phenamil, the most potent inhibitor known so far for the epithelium Na+ channel. [3H]Phenamil of high radioactive specific activity (30 Ci/mmol) was prepared and used to titrate [3H]phenamil binding sites in pig kidney membranes. Kinetic experiments, equilibrium binding studies, and competition experiments indicated the presence in crude membrane preparations of two classes of independent binding sites. A first binding site was characterized by a high affinity for phenamil (Kd1 = 0.4 nM) and for amiloride (Kd1 = 0.1 microM). A second binding site recognized phenamil and amiloride with lower affinities [Kd2(phenamil) = 28 nM, Kd2(amiloride) = 4 microM]. The ratio of the respective amounts of low- and high-affinity binding sites was 14 +/- 2 in different membrane preparations (range: 6-22). The two types of binding sites for [3H]phenamil copurified and were still observed after purification of the epithelium Na+ channel to homogeneity. These results indicate that at least two types of pharmacologically distinguishable Na+ channels exist in the kidney. They correspond either to two isoforms of the apical Na+ channel or to one single type of channel under two different states of covalent regulation.

Amiloride↗
PubMed1989

Arbaprostil [15(R)-15-methyl prostaglandin E2] in a single nighttime dose of either 50 or 100 micrograms in acute duodenal ulcer.

To determine the efficacy of single nighttime doses of arbaprostil [15(R)-15-methyl prostaglandin E2], 50 or 100 micrograms for 4 wk, a double-blind randomized placebo-controlled multiclinic trial was undertaken. Success was defined as complete healing of the ulcer documented by endoscopy. Fifty-one of 64 patients enrolled were considered evaluable. Ulcer healing was documented in 64.3%, 85.7%, and 31.2% of the 100-micrograms arbaprostil, 50-micrograms arbaprostil, and placebo treatment groups (p value vs. placebo = 0.003 and 0.002, respectively). No difference in side effects or changes in laboratory parameters were found between the treatment groups except that diarrhea, usually mild, was found more often in the 100-micrograms arbaprostil group (60.0%) than in the 50-micrograms arbaprostil (31.8%) or placebo groups (23.5%) (p value 100 micrograms arbaprostil vs. placebo = 0.02). A single nighttime administration of arbaprostil seems to be a safe and efficacious agent for the treatment of acute duodenal ulcer.

Adult↗
PubMed1989

Gastro-oesophageal reflux and respiratory disorders treated by Hill's procedure.

A retrospective review of 132 patients with respiratory disorders associated with gastrooesophageal reflux is presented. The patients were operated upon according to Hill's technique. In 66 infants and children, recurrent lung infection was the most frequent indication for surgery. The mean duration of respiratory symptoms was 17 months. In 66 adults, asthma was the most frequent indication for surgery. The mean duration of respiratory symptoms was 9.7 years. Suppression of reflux was obtained by operation in 95% of infants and children, with disappearance of respiratory disorders in 78.6% and clinical improvement of symptoms in 16.4%. Suppression of reflux was confirmed in 94% of adults, with disappearance of respiratory disorders in 36% and improvement of symptoms in 28%. The correlation between disappearance of reflux after surgery and cure of respiratory disorders in infants and children must be seen in the light of the natural history of lower oesophageal sphincter maturation. Nevertheless, surgery shortens the period of risk in life-threatening situations. In adults, one patient out of two benefited from operation. Failures were more frequent in asthma and there was no characteristic type of asthma associated with reflux.

Adolescent↗
PubMed1989

[Respiratory signs associated with gastro-esophageal reflux. A retrospective study of 132 surgically treated cases in children and adults].

We carried out a retrospective study of 132 cases of respiratory disorders associated with gastro-oesophageal reflux involving 66 children, 42 boys and 24 girls, 4 days to 10 years old with a mean of 22 months. We also studied 66 adults, 37 men and 29 women, 16 to 74 years old. In the infants the mean duration of respiratory disorders was 17 months and a recurrent broncho-pulmonary infection was the principal indication (40 cases). Alimentary symptoms were present in 34 cases. There was evidence of reflux in 60 cases. The suppression of any reflux was obtained surgically in 95% of cases with a disappearance of the respiratory disorders in 78.6% of cases and their improvement in 16.4% of cases with a mean follow up period of 4.3 years. In the adults the mean duration of the respiratory disorders was 9.7 years and asthma was the principal cause (38 cases). Alimentary symptoms were present in 56 cases with evidence of reflux in 64 cases. A suppression of the reflux was achieved surgically in 94% of cases with a disappearance of the respiratory disorders in 36% of cases and their improvement in 28% of cases with a mean follow up period of 4.7 years. The correlation between the disappearance of reflux and the respiratory symptoms and signs in the children should perhaps be tempered by the natural history of the maturation of the inferior oesophageal sphincter. However surgery shortens the danger period in serious situations which are life threatening.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1989

Percutaneous endoscopic gastrostomy made easier.

The use of a Fogarty catheter instead of a silk suture in performing an endoscopic gastrostomy offers several advantages. It avoids the problems of stomach deflation, the stomach slipping off the intravenous cannula, the troublesome passage of a soft suture through a small caliber tube and grasping a soft mobile object in the stomach.

Catheters, Indwelling↗
PubMed1988

Dietary intakes and nutritional status of old people with dementia living at home in Oslo.

A nutritional study was carried out of 16 independent-living elderly (9 women, 7 men) suffering from dementia and a control group matched for sex and age. The study consisted of interview (with participants or relatives/home helps), a 3-d weighed dietary record and biochemical determinations of blood components. No significant difference in mean daily energy intake between demented elderly (women 7.2 +/- 2.0 MJ, men 8.6 +/- 1.2 MJ) and controls (women 6.9 +/- 0.7 MJ, men 9.4 +/- 2.0 MJ) was found. The women with dementia had lower dietary intakes of protein (P less than 0.05), thiamin (P less than 0.05) and vitamin C (P less than 0.01) than female controls. For both sexes in both groups the nutrients most lacking were vitamin D and thiamin. Dietary supplements were more frequently used among elderly with dementia (50 per cent) than among controls (13 per cent) (P less than 0.05). Except for vitamin D, supplements did not reduce the number of demented elderly with low intakes (less than two-thirds of the recommendations) because generally those in most need were non-users. The demented elderly had lower levels of haemoglobin and folic acid (blood and plasma) (P less than 0.05) but better thiamin status (alpha-transketolase) than controls (P less than 0.05). No difference in mean levels of protein, 25-hydroxyvitamin D, vitamin E, vitamin B12 in serum was found. Individuals with blood or serum levels of nutrients below reference values were more frequently found among the demented elderly than among controls. In the dementia group 2 individuals with low levels of 25-hydroxyvitamin D also had clinical evidence of osteomalacia.

Aged↗
PubMed1987

[Partial splenectomy in non-traumatic benign lesions of the spleen].

Partial splenectomy was performed in a patient with cystic lymphangioma and two patients with splenic pseudo-cysts, one of traumatic origin and the other necrotic following infarct. Anatomical features on which this operation is based, together with the technique employed, are exposed and the criteria of efficacy examined. Partial splenectomy was performed to reduce splenomegaly complicated with hypersplenism, and is also applicable for exeresis of cystic and pseudo-cystic splenic lesions. These indications are worthy of more extensive application in young adults.

Adult↗
PubMed1986

Effect of alcohol consumption on serum concentration of 25-hydroxyvitamin D3, retinol, and retinol-binding protein.

The effect of chronic alcohol consumption on the concentration of 25-hydroxyvitamin D3, total retinol, and retinol-binding protein in serum was studied in chronic alcoholics (n = 12) and controls (n = 19). Ethanol intake during the last year was 178 +/- 116 and 3.7 +/- 4.5 g/day, respectively (p less than 0.002). Of the alcoholics, 58% had a concentration of 25-hydroxyvitamin D3 below lower limit of reference (20 ng/ml). Estimated dietary intake of vitamin D last year was not significantly different for the alcoholics and controls. Concentration of calcium in serum was significantly lower in alcoholics than in controls (p less than 0.05). The serum concentration of retinol and retinol-binding protein was similar in the two groups. These observations may be of relevance for some of the clinical findings related to bone disease among heavy alcohol consumers.

Adult↗
PubMed1985

[Massive rectal hemorrhage by colonic fistulization of a pancreatitis lesion].

Rectal hemorrhage of massive proportions in 4 patients was due to vascular erosion of a necrotic pancreatitis focus, and fistulization at the splenic angle of colon. This serious complication may arise during the course of acute pancreatitis or an acute episode of chronic pancreatitis. A literature review showed 22 similar cases reported. Diagnosis is suggested by the discovery of a stenosis of colon in a case of pancreatitis, and can be confirmed by emergency arteriography or operative findings. Hemorrhage is usually from the splenic artery but erosion of a left renal artery has been described. Treatment is by embolization during angiography followed by drainage of the pancreatic necrosis and a colon bypass operation, or by splenopancreatectomy combined with colectomy. Use of these two procedures led to recovery in the 4 cases reported.

Colectomy↗
PubMed1982

[Value of myoglobin radio-immuno-assay in myocardial infarction (author's transl)].

Serum myoglobin radio-immuno-assay was performed in 137 patients with myocardial infarction. Two groups, of 102 and 35 patients respectively, were seen in two different hospitals. Serum myoglobin was increased in 72 patients from the first group, and in 30 patients from the second group. In 10 patients from the first group, during the first 24 hours, the increase in serum myoglobin was isolated, without increase in CPK, LDH or SGOT. In the second group, a high serum myoglobin level with normal CPK was found in five patients. Increased serum myoglobin is not a specific indicator of myocardial infarction.

Angina Pectoris↗