H-2-dependent regulation of the high level of expression of ecotropic murine leukemia virus.

Adult B10.Y mice, which are congenic with C57BL/10ScSn ((B10) mice for the H-2 region, expressed a high titer of infectious ecotropic virus in the spleen. F1 hybrids between B10.Y and B10 mice were negative or had very low levels of virus expression. In (B10.Y x B10)F2 segregant mice, the high virus phenotype segregated with the H-2pa haplotype of B10.Y, whereas the virus-negative phenotype was associated with the H-2b haplotype of B10. Molecular hybridization experiments with a selected ecotropic AKR murine leukemia virus cyclic DNA probe indicated that both partner strains possessed ecotropic virus sequences and that the number of sequences present was the same in B10.Y mice as in B10 mice. This finding excluded the possibility that the H-2-related effect might be due to the presence of additional viral structural genes within or close to the H-2 region of B10.Y mice. The level of expression of this endogenous ecotropic virus was therefore affected by regulatory genes of the H-2 region.     

Platelet Functions in Cardiopulmonary Bypass Surgery

Background

Haemorrhage after Cardio Pulmonary Bypass (CPB) Surgery is a well recognised complication that leads to significant morbidity and mortality. The incidence varies between 5-25% depending upon the clinical situation. Several factors are implicated as causative but none have been precisely proved.

Methods

Our study was an attempt to evaluate the haemostatic defect with particular reference to platelet function abnormalities during cardio pulmonary bypass surgery, in order to reduce the morbidity and mortality associated with post CPB haemorrhage. Flow cytometric evaluation of different platelet glycoproteins like GPIb/IX, GPIIb/IIIa and GMP-140 was done.

Results

The marker expression showed deregulation during surgery which returned to base after bypass was terminated. In contrast, the cases with bleeding showed significant variation. P-Selectin (GMP 140) expression decreased progressively till 3^rd post-operative day showing lack of activation of platelets in cases of severe bleeding.

Conclusion

Longer duration of CPB initiates plasmin generation through heparin, which raises the PAI-1-tPA complex and thereby down regulating the functions of platelets. This suggests a link between duration of CPB, bleeding, platelet dysfunction and fibrinolysis. Hence serial estimations of the levels of GMP-140 and tPA can predict severe bleeding.Key Words: CardioPulmonary Bypass, Platelet dysfunction, flowcytometry, platelet glycoproteins, haemorrhage     

Membrane crystals of Ca2+-ATPase in sarcoplasmic reticulum of normal and dystrophic muscle

Two-dimensional crystalline arrays of the Ca2+ transport ATPase develop after treatment of sarcoplasmic reticulum vesicles with Na3VO4. The dimensions of the crystal lattice are similar in sarcoplasmic reticulum membranes isolated from normal and genetically dystrophic human, mouse, and chicken muscles. These observations indicate similar requirements for ATPase-ATPase interactions in sarcoplasmic reticulum of normal and dystrophic muscles and lessen the likelihood of a molecular defect of the Ca2+ pump in the various forms of genetic muscular dystrophies.     

Kynurenine metabolism in multiple sclerosis

Objective--Excitatory amino acid receptors are involved in the normal physiology of the brain, and may play a role in the pathogenesis of neurological disorders such as Huntington's disease, Parkinson's disease, amyotrophic lateral sclerosis, etc. It has been demonstrated that the blockade of one of these receptors ameliorates the symptoms of experimental allergic encephalomyelitis, an animal model of multiple sclerosis (MS). In a recent study, a decreased level of kynurenic acid was found in the cerebrospinal fluid of patients with MS. The only known endogenous excitotoxin receptor antagonist is the tryptophan metabolite kynurenic acid. Another metabolite is quinolinic acid, which exerts different action: it is an excitotoxin receptor agonist. The ratio of these two metabolites is determined by the activities of kynurenine aminotransferase I and II (KAT I and KAT II). In this study, we measured the activities of these enzymes and the concentration of kynurenic acid in the red blood cells (RBC) and in the plasma of patients with MS. KAT activities were detected both in the RBC and in the plasma. As compared with the control subjects, the KAT I and KAT II activities were significantly higher in the RBC of the patients. The concentration of kynurenic acid is elevated in the plasma of MS patients, and there is a tendency to an elevation in the RBC. These changes may indicate a compensatory protective mechanism against excitatory neurotoxic effects. Our data demonstrate the involvement of the kynurenine system in the pathogenesis of MS, which may predict a novel therapeutic intervention.     

Selective sensory denervation by capsaicin aggravates adriamycin-induced cardiomyopathy in rats

Capsaicin-sensitive sensory nerves that contain calcitonin gene-related peptide (CGRP) contribute significantly to cardioprotective mechanisms. In this study, the possible role of capsaicin-sensitive afferent nerves in the development of congestive heart failure was examined in an established model of adriamycin-induced experimental cardiomyopathy in rats. Systemic treatment with capsaicin was utilized to deplete sensory neuropeptides from cardiac afferent nerves. Echocardiography was applied to assess the cardiac function in adriamycin-treated rats pretreated with capsaicin or its vehicle. In control rats, adriamycin treatment produced a reduction in the fractional shortening of the left ventricle and an increase in the ratio of the left atrial diameter and the aortic diameter, indicative of a decreased myocardial contractility and heart failure only at 3–4 weeks post-treatment. In contrast, in capsaicin-pretreated rats, a deterioration of the cardiac function was already evident 1 week after the cessation of adriamycin administration, while the clinical signs associated with cardiomyopathy were more severe and displayed a significantly more rapid progression. Immunohistochemistry revealed a complete depletion of calcitonin gene-related peptide from cardiac sensory nerves after systemic capsaicin treatment. This study has demonstrated that elimination of capsaicin-sensitive afferent nerves promotes the development and progression of adriamycin-induced myocardial dysfunction. The results suggest that interfering with capsaicin/vanilloid receptor function and/or perturbation of the myocardial CGRP metabolism may open up new perspectives concerning prevention and/or alleviation of the pathological changes that follow adriamycin treatment.     

葛根素对高血压患者血浆内皮素和一氧化氮的影响

目的：检测正常人与高血压病（ＥＨ）患者血浆内皮素、一气体氮的变化及葛根素对其的干预效应。方法：ＥＨ对照组口服苯磺酸氨氯地平５ｍｇ／ｄ,或合和盐酸苯那普利１０ｍｇ／ｄ,每日一次,１５ｄ为一疗程。ＥＨ伍用治疗组同时合用５％ＧＮＳ２５０ｍｌ＋葛根素注射液４００ｍｇ静滴,两组治疗前后检测血浆ＥＴ、ＮＯ水平变化。结果：ＥＨ各组血浆ＥＴ较正常人组均显著增高（Ｐ〈０．０１）,血浆ＮＯ水平及ＮＯ／ＥＴ比值除轻度Ｅ     

Outcome after Metatarsal Osteotomy for Hallux Valgus: A Study of Postoperative Foot Function Using Revised Foot Function Index Short Form

The aim of the present study was to evaluate patients' perception of their functional outcome at 6 and 12 months after surgical correction for hallux valgus using the Foot Function Index Revised short form. A total of 59 patients underwent 68 osseous and soft tissue procedures for the correction of hallux valgus deformity from January 2009 through December 2010. The outcome analysis was based on the validated patient questionnaire, the Foot Function Index Revised. The preoperative data were collected on the day of the patient's surgery using the Foot Function Index Revised short-form questionnaire. The postoperative data were collected at 6 and 12 months after the patient's initial surgical date using the same validated questionnaire. The cumulative Foot Function Index Revised score and the scores in each subscale demonstrated statistically significant data at both 6 and 12 months of follow-up. On average, the Foot Function Index Revised scores had improved by 39% at 6 months and 50% at 12 months. The improvement in all scores indicated an improvement in health-related foot function after hallux valgus surgery, evidencing effective surgical intervention. Expectations are the best predictors of patient satisfaction, and the present study has provided statistically significant data to allow physicians to establish realistic outcomes after surgical correction for hallux valgus deformity.