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Biomedical subjects

R Albrecht

Publications and source records attributed to R Albrecht.

At least 73 records · Page 4Linked to original sources
PubMed1989

Probable exclusion of juvenile neuronal ceroid lipofuscinosis in a fetus at risk: an interim report.

In a family with two children affected by juvenile neuronal ceroid lipofuscinosis (JNCL) an attempt was made at the prenatal diagnosis of the disorder. The following tissues from the fetus at risk were investigated by electron microscopy and were found to be free of fingerprint profiles and curvilinear bodies, typical for JNCL: uncultivated amniotic fluid cells, lymphocytes isolated from fetal blood, and fetal skin biopsy specimens. The child was born at the 34th week of gestation and was clinically normal at the age of 15 months. Postnatally, lymphocytes (isolated at the age of 6 and 15 months) and skin tissue (taken at the age of 15 months) were found to be morphologically normal. It is highly unlikely that the child is affected but definite proof of the absence of JNCL remains difficult at this age.

Amniocentesis↗
PubMed1989

Cardiovascular correlates of type A behavior components during social interaction.

This study examined the cardiovascular (CV) correlates of the primary Type A behavior components during social interactions. Brief dialogues were created to role-play (RP) stereotypic Type A and Type B ways of responding to three common social situations designed to elicit hostility (H), time-urgency (T), and competition (C). Situations and dialogues were validated by independent raters. Thirty undergraduate students were identified as Type A and 30 as Type B, with 15 males and 15 females in each group. Subjects were provided scripts for each of the six experimental RPs and rehearsed them prior to the CV assessment. Measures of systolic and diastolic blood pressure (SBP, DBP) and heart-rate (HR) were obtained during an adaptation period and during each RP. Analyses of the "A" (i.e. H, T, C) versus "B" (i.e. non-H, non-T, non-C) RPs indicated that DBP (p less than 0.03) and HR (p less than 0.002) were higher during the H as compared with non-H RP. Significantly higher SBP was observed in the T as compared with the non-T RP (p less than 0.04). No CV differences were observed in the comparison of the C and non-C RPs. Analyses comparing the three "Type A" RPs revealed higher SBP during H and T RPs, as compared with the C RP (p less than 0.003). Effects of subject Type (i.e. A/B) were not obtained in any analysis. These findings indicate that hostile and time-urgent social interactions are associated with significant increases in CV arousal which are independent of overall Type status.

Adult↗
PubMed1989

Effects of prototypic PCBs on benzo[a]pyrene mutagenic activity related to vitamin A intake.

The effects of vitamin A dietary intake (2 and 20 IU */g of food) on the mutagenic activity of benzo[a]pyrene (B(a)P) toward Salmonella typhimurium (TA98) were studied either in control rats or in animals treated by the PCB congeners 2,4,5,2',4',5'-hexachlorobiphenyl [2,4,5)2Cl) and 3,4,3',4'-tetrachlorobiphenyl [3,4)2Cl). (3,4)2Cl (a planar compound) strongly increased B(a)P monooxygenase (B(a)PMO) activity and glutathione transferase, (2,4,5)2Cl (a non-planar PCB) was a strong inducer of epoxide hydrolase and a weak inducer of B(a)PMO. Enzyme induction was not modified by changes in vitamin A dietary intake. A higher mutagenic effect was observed in the (3,4)2Cl group than in the (2,4,5)2Cl one. This could be related to the specific form of cytochrome P-450 induced by (3,4)2Cl. In the untreated animals, the activation of B(a)P was higher in the 2-IU group than in the 20-IU one. Conversely, in PCB-treated rats the mutagenic activity of B(a)P was higher in the 20-IU group than in the 2-IU one. PCB induction increased the liver content of vitamin C in both the 2-IU and the 20-IU groups but only increased the glutathione levels in the 2-IU groups. This suggests that glutathione content in cellular fractions may be one of the determining parameters for the mutagenic activity of B(a)P.

Animals↗
PubMed1989

[Gastric perfusion in the rat--a method for determining gastric secretion].

The response of the 3 postulated receptors in the parietal cell was investigated by means of a perfusion model in the rat. It was compared the effect of cimetidine and atropine on pentagastrin, histamine and carbachol stimulated gastric acid secretion with a control group. Atropine blocked the carbachol stimulation totally but did not effect pentagastrin and histamine stimulation. Cimetidine inhibited all stimulations. This method is a model for study of drugs influences of the gastric secretion.

Animals↗
PubMed1988

[Syndrome following injury of the ventromedial hypothalamic nucleus (VMH syndrome) and its relation to increased secretion of gastric acid (hyperchlorhydria)--an experimental study with rats].

In rats a stereotactic electrocoagulation of the Nucleus ventromedialis hypothalami (NVM) leads to a VMH syndrome (ventromedial hypothalamic syndrome) with hyperphagia, adiposity, and hyperinsulinaemia. A less known fact in this connection is the increased secretion of gastric acid (hyperchlorohydria). We could prove that the basal gastric secretion increases after NVM lesions by two times (from 18 mumol H+/hr to 37 mumol H+/hr) and that this hyperchlorohydria can be removed by a vagotomy. From this fact one can derive conclusions concerning the acute gastric mucous secretion after brain lesions with regard to their pathogenesis and therapy.

Animals↗
PubMed1988

[Increased cholinergic stimulating gastric secretion after truncal vagotomy in rats].

The reasons of the relapses after vagotomy are not clarified completely. The reactivity of the 3 postulated receptors in the parietal cell was investigated by means of a perfusion model in the rat in a control group and after truncus vagotomy 28 days before the experiment. Not any difference was shown between the control group or the vagotomy group after histamine and pentagastrin stimulation. A significant greater secretion (!) with negative insulin test was observed in the vagotomy group after carbachol stimulation.

Animals↗
PubMed1987

The effect of dietary imbalances on the activation of benzo[a]pyrene by the metabolizing enzymes from rat liver.

Male Sprague-Dawley rats (70-80 g) were fed ad libitum a standard control diet (22% casein, 5% lard), or a high lipid diet (30% lard) or a low protein diet (6% casein) or a standard diet containing 50 ppm phenoclor DP6. After 6 weeks on these diets, the cytochrome P-450 microsomal content, the benzo[a]pyrene monooxygenase (BaP-MO) and the epoxide hydrolase (EH) were assayed. The formation of mutagenic B(a)P metabolites which covalently bind with DNA was compared. The activity of BaP-MO and of EH were increased by the high lipid diet (+27% and 106% respectively) and by the phenoclor DP6 treatment (+63% and 400% respectively), compared to the standard diet. In animals fed a low protein diet the BaP-MO was decreased (-34%) and the EH activity was strongly increased (+262%) compared to those fed a standard diet. All experimental diets increased both the activation of BaP to metabolites able to bind DNA and the mutagenicity of BaP versus TA98 Salmonella typhimurium strain. It was concluded that dietary imbalances can be considered as a factor in chemical carcinogenesis.

Animals↗
PubMed1987

[Carbachol-pentagastrin-induced duodenal ulcer in rats and its relation to gastric acid secretion].

Duodenal ulcers were produced in rats by the subcutaneous infusion of carbachol and pentagastrin in combination. We determined the gastric acid output using a perfusion method, when carbachol or pentagastrin were infused alone or in combination. In combination we saw a maximum acid output. Atropine blocked a carbachol stimulation totally but did not affect pentagastrin stimulation. Infusing rats subcutaneously with carbachol/pentagastrin and applicating atropine I.V. rats did not develop duodenal ulcer. This method of secretagogue produced duodenal ulcer is a model for study of anticholinergic influences of the gastric secretion.

Animals↗
PubMed1987

[Does extensive small intestine resection prevent experimentally induced duodenal ulcers? A study on rats].

Our previous results showed that pentagastrin stimulated gastric secretion (peak acid output) was significantly decreased following extensive distal small bowel resection. The aim of this study was to see the effect of extensive small bowel resection on experimental duodenal ulcers 28 days after operation. We used secretagogue-produced duodenal ulcers in the rats. Vagotomy prevented these experimental ulcers but not gastric mucosa lesions. Extensive small bowel resection both proximally and distally prevented secretagogue-induced duodenal ulcers too, but there was a mucosa protection both in gastric antrum and duodenal bulb. We concluded this protective effect may be due to compensatory mucosa hyperplasia following extensive small bowel resection.

Animals↗
PubMed1986

[Protein restriction and metabolism of xenobiotics].

Young male rats were fed a balanced diet or a low-protein diet (casein 6%; w/w) for 6 weeks. After 2 weeks, each group was divided, one half being maintained as the control and the other half being fed diet-containing (Phenoclor DP6) at a level of 50 mg/kg for 4 weeks. A low-protein diet lowered the liver glutathione content and the activity of the mono-oxygenases. It lowered the inductive effect of PCB towards P450, NADPH-cytochrome c reductase, aminopyrine demethylase and aniline hydroxylase, but it raised the benzo(a) pyrene hydroxylase induction.

Aminopyrine N-Demethylase↗
PubMed1985

Acquired cystic kidney disease--a possible pitfall in genetic counseling.

A case of a 24-year-old pregnant woman on dialysis who asked for genetic counseling is reported. Differentiation between nonheritable acquired cystic kidneys and autosomal dominant polycystic kidney disease without noninvasive diagnostic procedure was nearly impossible in the reported woman. The communication underlines the problem and gives diagnostic criteria.

Adult↗
PubMed1985

Tissue distribution and ultrastructure of B lymphocytes reacting with the monoclonal antibody anti-Y29/55.

The reactivity of normal tonsilar cells with the monoclonal antibody anti-Y29/55 is characterized at the tissue and ultrastructural cytological level. Using an indirect immuno-alkaline phosphatase method on frozen sections the antibody labels mantle zone and germinal center lymphocytes. This staining reaction is more generalized in B-lymphocyte areas than that obtained with antibodies to IgM and IgD. By indirect immunoperoxidase staining, as well as by an indirect rosetting procedure in cell suspensions, the reactive cell population were either small resting lymphocytes or activated lymphocytes corresponding to centrocytes, centroblasts, immunoblasts and plasmoblasts; some plasma cells were also labeled. These results characterize the monoclonal antibody anti-Y29/55 as a pan-B-marker antibody, useful for labeling resting and activated peripheral B-lymphocytes in frozen tissue sections and cell suspensions.

Animals↗
PubMed1985

[Polychlorobiphenyl (Phenoclor DP6) and the metabolism of xenobiotics: effect of a high lipid diet].

Young male rats were fed a balanced diet or a hyperlipidic diet (lard 30%, w/w) for 6 wk. After the first 2 wk each group was divided, one half being maintained as the control and the other half being fed the same diet with a polychlorinated biphenyl (Phénoclor DP6) added at a level of 50 mg/kg diet for 4 wk. In animals fed the balanced diet, DP6 increased the microsomal-protein and cytochrome P-450 content and the specific activity of the monooxygenases. The high-fat diet increased the inductive effect of DP6 on cytochrome P-450, aminopyrine demethylase and benzo[a]pyrene hydroxylase, but not on aniline hydroxylase or cytochrome c reductase.

Administration, Oral↗
PubMed1985

[Hyperchlorhydria of the stomach following hypothalamus lesions in the rat].

Effects of ventromedial hypothalamic (VMH corresponding Nucleus ventromedialis hypothalami NVM) lesion on gastric acid output were examined. Acid output was determined by using the gastric perfusion method in rats anesthetized with urethan. With lesion of the ventromedial hypothalamus a significant increase in acid output occurred 28 days after lesion. Basal acid output increased from 5.9 +/- 2.5 to 32.2 mumol H+ X h-1 and stimulated acid output increased from 15.4 +/- 7.2 to 75.3 +/- 15.3 mumol H+ X h-1. Gastric hypersecretion in rats with VMH lesions was due to a vagally-mediated gastric stimulation. This model is useful to trial drugs which reduce gastric acidity.

Animals↗
PubMed1984

[Blood glucose determination at the bedside with test strips and reflection photometer: comparison of 2 instruments with a standard method].

The accuracy of blood glucose measurements was evaluated with two different test strip-reflection photometer systems (Reflolux and Reflocheck). Two experienced technicians took 92 measurements in capillary blood at the bedside and the results were compared with a reference value obtained from the same capillary blood sample by a standard automated glucose oxidase method. Both test strips agreed well with the reference value, with high correlation coefficients and with total errors of less than 25%. It remains to be established whether the two methods are as reliable when performed by patients themselves.

Blood Glucose↗
PubMed1984

Dysautonomia in Guillain-Barré syndrome with dorsal root ganglioneuropathy, wallerian degeneration, and fatal myocarditis.

An acute Guillain-Barré syndrome presenting as dysautonomia is described in a 12-year-old boy. The patient died of intractable cardiac arrhythmias and cardiac failure. A severe myocarditis with destruction of dorsal root ganglion cells and wallerian degeneration of dorsal roots and peripheral nerves was apparent postmortem. Segmental demyelination and inflammatory cellular infiltrations were not present at these sites.

Autonomic Nervous System Diseases↗
PubMed1984

Lipid composition and monooxygenase relationship in liver microsomal membranes from rats fed unbalanced diets.

The cholesterol and phospholipid content of microsomal membrane from rats fed either a high lipid (H1) (30% lard) or a low protein (Lp) diet (6% casein) have been compared with those from rats fed a standard (St) diet (22% casein, 5% lard). For each diet, half of the group was treated with Phenochlor DP6. A significant increase in the phospholipid cholesterol ratio was observed in rats fed a high lipid diet or treated with DP6. These effects tend to increase the microsomal membrane fluidity. The protein deficiency decreased the phospholipid/cholesterol ratio and then the fluidity of the endoplasmic reticulum membrane. The specific activity of cytochrome P-450 to hydroxylate aniline which is independent to the enzymic form of cytochrome P-450 was closely correlated with the viscosity status of the microsomal membrane.

Aniline Hydroxylase↗