Modulatory role of serotonin on GABA-elicited inhibition of cerebellar Purkinje cells

The present study was designed to directly examine the postsynaptic actions of serotonin on GABA-mediated inhibition of cerebellar Purkinje cells. The findings indicate that serotonin at currents that produced minimal effects on the spontaneous firing rates of Purkinje cells modified GABA effects in a biphasic manner. Serotonin initially decreased GABA-mediated inhibitions followed secondarily by either continued inhibition or, in the majority of cases, augmentation of GABA responses. When a comparison was made of the secondary effects of serotonin on GABA-mediated inhibition with the initial spontaneous firing rates of the Purkinje cells, the group in which serotonin augmented GABA actions had a significantly higher initial firing frequency than the group in which serotonin attenuated GABA-mediated inhibition. Furthermore, with increasing firing rates, the proportion of cells showing augmentation of GABA inhibition increased, and the proportion of cells displaying attenuation of GABA effects decreased. Serotonin affected beta-alanine-mediated inhibitions in a manner similar to that seen with GABA, whereas glycine was differentially altered. This study identifies another neuromodulatory role of serotonin on Purkinje cells in the cerebellum. Furthermore, the effects of serotonin on GABA inhibition seem to be governed by some intrinsic property of the Purkinje cell, which is apparently related to the firing rate of the cell.     

Kinetics and specificity at the clonal level of the cytotoxic T lymphocyte response to influenza pneumonia

We have studied the kinetics and specificity of the cytotoxic T lymphocyte (CTL) response to influenza A/PR/8 (H1N1) virus pulmonary infection in the mouse detected using spleen cells from infected mice which were stimulated in bulk and limiting dilution cultures. A hybrid protein designated D-peptide, which contains the terminal 157 amino acids of the HA2 subunit of A/PR/8 virus, was used to stimulate influenza virus subtype-specific secondary CTL in vitro. Infection induced two specificities of precursor CTL, cross-reactive and subtype-specific. The kinetics of the subtype-specific CTL response detected by the D-peptide were similar to the cross-reactive CTL response detected by stimulation with live virus. The majority of the precursor CTL (CTL-p) are able to lyse virus-infected target cells in a cross-reactive fashion. The number of memory subtype-specific and cross-reactive CTL increased by approximately 2.5 logs10 during the first 3 weeks after infection.     

纤维连接蛋白与动脉粥样硬化的关系

炎症机制在动脉粥样硬化斑块的发生、发展中扮演了重要角色。近年来,不断有研究证实前炎性因子纤维连接蛋白(fibronectin,Fn)密切参与了此过程,并与急性冠状动脉综合征的发生有着极强的关联性。本文就Fn与急性冠状动脉综合征的关系及其应用前景进行综述。     

Ethnic variation in cholecystectomy rates and outcomes, Manitoba, Canada, 1972-84.

We used population-based data from the Province of Manitoba's universal health insurance plan to compare the cholecystectomy experience of Native Americans and non-Natives from 1972 to 1984. The age-adjusted cholecystectomy rates for Native females were higher than for non-Native females with the peak rate occurring at age 30-39 for Native Americans and at age 60-69 for non-Natives. The rates for males were three times lower than for females and did not differ between Natives and non-Natives. Native Americans were more likely readmitted to hospital for surgical complications than non-Natives and this held true after controlling for age, sex, rural versus urban residence, teaching versus non-teaching hospital, multiple discharge diagnoses or complex versus simple cholecystectomy (relative odds 1.46, 95 per cent confidence interval 1.17, 1.18). The explanation for the relatively high rates of cholecystectomy among Native American females may be related to high rates of known risk factors for gallstone disease (such as obesity and high parity). However, the higher rates of surgical complications require further study.     

Clinical and immunological results of corneal allograft rejection

Of 111 episodes of graft rejection in 66 patients, 62 responded to therapy with graft clearing (responders); 49 did not (non-responders). Both groups were of similar age, sex, and etiology; both had a similar rate of glaucoma and a similar rate of previous grafting. In responders the graft reaction was shorter in duration (2.2 vs. 5.6 wks. p less than 0.005), and it was necessary to increase the number of glaucoma medications more often in non-responders compared to responders (41% vs. 19%, p less than 0.02). The interval from surgery to reaction was similar in responders and non-responders (18.2 vs. 13.3 mos., p greater than 0.1). An epithelial rejection line was present in 11% of responders, but was not present in non-responders (p less than 0.05). Lymphocytotoxic antibody development correlated with rejection in 16 of 64 episodes. Patients who responded to treatment were more frequently asymptomatic (p less than 0.05) or were treated earlier following the onset of symptoms compared to non-responders (p less than 0.0001).     

Flavonoids from the leaves ofRhododendron brachycarpum

The flavonoids isolated from the leaves ofRhododendron brachycarpum, were identified as quercetin, avicularin, quercitrin and hyperin.     

输精管结扎对家兔心功能及心肌NE含量的影响

本实验用日本大耳白兔复制输精管结扎的长期动物模型，分为结扎２５月组（ＶＧ２５），同龄假手术２５月组（ＳＯＧ２５）；结扎６月组（ＶＧ６），同龄假手术６月组（ＳＯＧ６）。记录各组家兔心功能，检测心肌及血清ＮＥ含量，称取心重（ＷＨ）。结果表明，左心室收缩期末压（ＬＶＳＰ），ＶＧ略高于ＳＯＧ；左心室舒张末压（ＬＶＥＤＰ），Ｖ６２５显著的低于ＳＯＧ２５Ｐ＜０．０５），ＶＧ６与５ＯＧ６比较虽无显著差异，也呈低值；±ｄｐ／ｄｔｍａｘ，ＶＧ均明显高于ＳＯＧ（Ｐ＜０．０１）。相关检验表明，＋ｄｐ／ｄｔｍａｘ与血清及心肌ＮＥ含量无相关性；心重与＋ｄｐ／ｄｔｍａｘ呈明显正相关，Ｐ＜０．０５；在２５月组，ＬＶＳＰ与＋ｄｐ／ｄｔｍａｘ呈正相关，Ｐ＜０．０５。提示输精管结扎可提高心肌收缩功能。     

The pathogenesis and clinical significance of traumatic subdural hygroma

Subdural hygroma (SDG) is a common post-traumatic lesion. Despite its common occurrence, the pathogenesis and clinical significance are uncertain. The author reviewed the literature to clarify the present knowledge on the pathogenic, diagnostic and therapeutic aspects of this controversial lesion. A trivial trauma can cause a separation of the dura-arachnoid interface, which is the basic requirement for the development of a SDG. If the brain shrinks due to brain atrophy, excessive dehydration or decreased intracranial pressure, fluid collection may develop by a passive effusion. Most SDGs resolve when the brain is well expanded. However, a few SDGs become chronic subdural haematomas, when the necessary conditions persist over several weeks. Since the majority of patients with a SDG do not show a mass effect, surgery is rarely required. Outcome is closely related to the primary head injury not to the SDG itself. The complexity of SDG depends on various factors including the dynamics of absorption and expansion, duration of observation, and indication and rate of surgery, besides variety of the primary head injury in types and severity. SDG is a common epiphenomenon of head injury.