Smoking and coffee intake following alcohol withdrawal in alcoholic inpatients

The aim of this study was to assess alcoholic inpatients' smoking and coffee intake variation following withdrawal. Only moderate smokers (less than 30 cigarettes/day) showed a significant increase of cigarette consumption after alcohol withdrawal. However, their urinary cotinine level did not vary, suggesting a behavioral, and not biological, compensation through smoking following alcohol withdrawal. Heavy smokers (30 cigarettes/day or more) showed no significant clinical or biological variation of smoking behavior. Coffee consumption increased after alcohol withdrawal in all patients, irrespective of smoking habits.     

聚合酶链反应产物特异性的阳性证实

以聚合酶链反应(PCR)法在mRNA水平检测T淋巴细胞受体α链可变区基因表达为例,介绍用~(32)P标记的人工合成寡核苷酸探针对PCR产物特异性作阳性证实的方法。该法以干琼脂糖凝胶作为支持物、相对较为简便和省财。用Ca探针以干凝胶作支持物的杂交结果,证实29个Vα基因的PCR扩增中物均为特异性的,放射自显影的带型与位置和溴乙锭染色所示完全吻合。     

Synaptic plasticity in the dentate gyrus of aged rats is altered after chronic nimodipine application.

We examined ultrastructural correlates of synaptic plasticity in the hippocampus of young (3 months) vs aged (30 months) Wistar rats and established the effects of the calcium antagonist nimodipine in animals chronically treated from 24 to 30 months. The effects of nimodipine was studied since this compound improves hippocampal neuronal physiology and enhances cognitive function during aging. In the supragranular layer of the dentate gyrus we found a 24% decrease in synaptic density (Nv) in aged animals, while synaptic size (S) was not significantly altered. After nimodipine treatment Nv in aged rats was not significantly different from young adults, thus being significantly increased compared to age-matched controls. The size of synapses was not significantly altered after nimodipine administration. Total synaptic surface area (Sv) in nimodipine-treated animals was significantly increased compared to aged controls, however, Sv remained significantly lower than in young adults. These data indicate that chronic administration of nimodipine enables granular cells in the dentate gyrus to maintain its number of synaptic contacts during the aging process. Furthermore, the presented influence of nimodipine on synaptic plasticity processes may underlie previously reported improved cognitive functioning of aged animals treated similarly with nimodipine.     

Validation in the sheep of an ultrasound velocity dilution technique for haemodialysis graft flow

BACKGROUND: A simple, rapid, inexpensive method for measuring the flow in a patient's vascular access would permit routine monitoring during haemodialysis, and hence provide information of access graft deterioration sufficiently early to increase the success of minimally invasive remedial procedures. This paper reports the validation of such a method in animals. METHODS: A PTFE graft was implanted in sheep between the carotid artery and the jugular vein. While the sheep was under general anaesthesia and on an haemodialysis circuit, ultrasound velocity in its blood was perturbed by the injection of a 5-10 ml bolus of isotonic NaCl. The pump tubing flow was measured by a transit-time blood flow meter. This flow was combined with the areas of perturbation generated by the injection before and after mixing in the access flow to estimate graft flow. The calculated graft flow was compared to flow measured directly by a transit-time probe on the same carotid artery. RESULTS: Over a 10-fold range, 120-1260 ml/min, graft flow measured by ultrasound velocity dilution agreed well with graft flow measured directly with a scatter of 76 ml/min about the regression line. CONCLUSION: Ultrasound velocity dilution provides a method for measuring flow in the graft accurate enough for clinical evaluation of patients on dialysis.      

Evidence for a human IgG1 class switch program

In activated murine B lymphocytes, immunoglobulin class switch recombination occurs as a highly regulated process which is targeted to distinct switch regions. Here we present first evidence that in human B lymphocytes, switch recombination is targeted to distinct switch regions as well. In a panel of clonally unrelated IgG1-expressing human B cells, immortalized by Epstein-Barr virus (EBV) transformation, seven out of nine cells show switch recombination between Sμ and Sγ1 on both alleles, the active and inactive one. The remaining cells show no switch recombination on the inactive IgH locus. The very strong correlation of switch recombination on both alleles of IgG1-expressing cells proves that class switch recombination to IgG1 is not random but directed in human B lymphocytes.     

Alterations in the cortical thymic epithelium of rats after in vivo exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD): an (immuno)histological study.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) induces thymic atrophy in rats. The present study was initiated to provide (immuno)histological data on the mechanism of action. Juvenile male Wistar rats were orally intubated once with 50 or 150 micrograms/kg TCDD. They were euthanized 4 or 10 days thereafter, or were allowed to stay alive until Day 20 or 26. Growth retardation occurred rapidly in all TCDD-treated animals. Lethality was demonstrated within 20-21 days after administration. At Days 4 and 10 after intubation, thymic atrophy was shown by reduction of thymic weight and cortex/medulla ratio. Staining patterns for T-cell markers in the atrophic thymuses coincided with the reduction of cortical areas. There was no evidence indicating that the effects were indirectly caused by stress. TCDD-induced thymic atrophy persisted until Day 26 after administration. Immunohistochemical analysis revealed prominent changes in the cortical thymic epithelium at the 150-micrograms/kg dose level. First, in the cortex epithelial cell aggregates were observed both at Day 4 and at Day 10 after administration. Apparently, the architecture of the epithelium had changed in these animals. Second, at 10 days after administration epithelial cells were found with the simultaneous expression of markers that in the normal uninvoluted thymus only occur either in the subcapsular/medullary area or in the cortex. This phenotype points to an unusual stage of differentiation. We conclude that TCDD exposure affects the cortical epithelium of the rat thymus at a high dose level. Apparently, it disturbs the epithelial network and interfers with the differentiation of epithelial cells.     

Three years experience with denaturated venous homografts as an arterial substitute: a clinical, pathological and immunological study

Over a three-year-period 105 peripheral arterial reconstructions were performed using a denaturated venous homograft in a group of patients with no suitable autologous vein. A retrospective analysis has been carried out to investigate the patency rate of this graft. After three years 64% of all grafts are functioning well (according to the Life Table Method, Kaplan & Meyer). No significant differences in patency rates were found between reversed autologous veins and the material tested in this study but analysis of grafts removed after failure showed obstruction due to thrombosis or aneurysmal dilatation. No evidence of an immune response to the grafts was seen.     

Combination of ABO blood group incompatibility and glucose-6-phosphate dehydrogenase deficiency: effect on hemolysis and neonatal hyperbilirubinemia

The incidence (%) of hyperbilirubinemia (serum bilirubin ≥257 μmol/l) was similar in neonates with a combination of ABO incompatibility and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency (45%), with ABO incompatibility (54%) or G-6-PD deficiency (37%), alone (ns). Carboxyhemoglobin values, corrected for inspired CO, were similarly elevated in all three groups (0.87 ± 0.32%, 0.82 ± 0.29%, 0.76 ± 0.18%, respectively, ns), but correlated with bilirubin only in those with ABO incompatibility alone. ABO-incompatible/G-6-PD-deficient neonates, compared with those with either condition alone, are not at increased risk for hemolysis or hyperbilirubinemia.