人参根总皂甙对效应激小鼠免疫功能的影响

小鼠在45℃高温环境下暴露15min,其网状内皮系统对碳粒的廓清作用明显降低,血清溶血素含量显著下降,绵羊红细胞(SRBC)诱发的迟发型超敏反应明显受到抑制.应激前15min人参根总皂甙(GRS)50、100 mg·kg~(-1),ip,对小鼠的免疫功能有保护作用,可使热应激小鼠网状内皮系统对碳粒的廓清作用免于下降,防止血清溶血素含量的降低,迟发超敏反应不受抑制.     

Patch testing with beryllium alloy samples in guinea pigs

An experimental study was conducted in guinea pigs for the predictive assessment of the beryllium alloy hazard in occupational exposure of the skin to beryllium compounds. Guinea pigs were sensitized to beryllium sulfate according to the maximized Magnusson and Kligman test, and challenged with beryllium alloys and metallic copper, beryllium and aluminum samples. Results showed a delayed skin hypersensitivity reaction in 30 to 60% of pre-sensitized guinea pigs challenged with copper-beryllium alloys and aluminum-beryllium alloy. An inflammatory follicular reaction was induced by copper in both controls and pre-sensitized guinea pigs.     

胰岛素对数种缩血管物质作用的影响

目的 观察胰岛素对去甲肾上腺素、内皮素-１、氯化钾（ＫＣＩ）、血管紧张素Ⅱ和５－羟色胺缩血管作用的影响。方法 用ＳＤ大鼠的离体动脉血管观察缩血管物质的作用。结果 在含有１ｍＵ／ｍｌ胰岛素环境中，胰岛素对数种缩血管作用机制不同的物质有程度不同的血管增敏作用。对去甲肾上腺素、内皮素－１和ＫＣＩ有明显的增敏效果；对血管紧张素Ⅱ有增敏趋势，但无显著性差异；对5－羟色胺无增敏效应。结论 胰岛素在高血压的发病过程中可能起重要作用。     

Keratinocyte-derived Cytokines and UVB-Induced Immunosuppression

Ultraviolet radiation (UVB) in sunlight is known to have multiple effects on the immune system. Evidence suggests that UVB-induced immunosuppression is mediated in part by immunosuppressive and immunoregulatory cytokines. Our studies have utilized gene-targeted mutant mice to determine key molecular requirements essential for the development of UVB-induced immunosuppression. Preliminary results from our laboratory suggest that TNF-α plays a regulatory role in contact hypersensitivity, but is not a crucial factor for UVB-induced immunosuppression, and that multiple factors are involved in the induction of UVB mediated immunosuppression.     

镉对小鼠免疫功能的影响

采用单只动物多项免疫功能检测法,观察了小鼠在免疫后,不同时间一次灌胃30mg/kg氯化镉(CdCl_2)及反复多次灌胃不同剂量的CdCl_2,对小鼠免疫器官重量,迟发型变态反应(DTH),抗体形成细胞(IgM-PFC)及抗体滴度的影响。结果表明:反复多次灌胃4.8 mg/kg CdCl_2对小鼠DTH有明显抑制作用,提示CdCl_2对动物免疫功能有一定影响。     

Functional dyspepsia: New insights into the pathophysiology

Abstract The pathogenesis of functional dyspepsia remains poorly understood. There is increasing evidence pointing to a predominant role of gastroduodenal visceral hypersensitivity in the pathogenesis, where patients have abnormally reduced gastric and small intestinal sensory thresholds. Motor abnormalities observed in subgroups of patients include delayed gastric emptying, antral hypomotility, gastric dysrhythmias, abnormal gastrointestinal reflexes and small intestinal dysmotility, but these may be secondary pheno nena. The central nervous system modifies peripheral visceral afferent pathways and, hente, psychological factors may possibly alter symptom status. Other putative mechanisms include Helicobacter pylori gastritis and gastric acid hypersecretion or sensitivity, but the role of these remain controversial.     

Guinea pig maximisation test for skin sensitisation: the use of fewer test animals

Current European Community (Annex V) guidelines recommend the use of 20 test animals in the guinea pig maximisation test for skin sensitisation. The suitability, for classification and labelling purposes, of reducing the number of test animals has been examined by analysing the results of 40 studies submitted to the Health and Safety Executive, and by the use of a mathematical model. Our results suggest that in most cases an experiment with ten test animals can be used to determine satisfactorily whether a substance should be labelled with the risk phrase may cause sensitisation by skin contact. However, serious consideration should be given to the need for additional investigation if two or three of the ten test animals show a sensitisation response. The highest nonirritant concentration of a substance should be used at challenge. Clearer guidance in Annex V on evaluating challenge responses would be beneficial.     

Identical expression of ELAM-1, VCAM-1, and ICAM-1 in sarcoidosis and usual interstitial pneumonitis

Extravasation of leucocytes in tissues is mediated by leucocyte—endothelial cell interactions in which adhesion molecules play an important role. Until now, two pathways have been unravelled, i.e., the LFA-1/ICAM-1 and the VLA-4/VCAM-1 pathways. ELAM-1 has been shown to be involved in granulocyte accumulation and recently also in lymphocyte migration. The role of HECA-452 is under investigation. In this study we have investigated the expression of the above-mentioned adhesion molecules in lung tissue of patients with pulmonary sarcoidosis and usual interstitial pneumonitis (UIP), and in mediastinal lymph nodes of patients with sarcoidosis. ICAM-1 (CD54) was broadly distributed on the endothelium of all the vessels found in sarcoidosis and UIP. VCAM-1 was present on the endothelium of the venules, capillaries, and arterioles in both sarcoidosis and UIP. ELAM-1 reacted with endothelial cells lining venules and capillaries in chronic progressive sarcoidosis and in the active phase of UIP but not in the stationary phases of both diseases. HECA-452 activity could be detected only on high endothelial venules within sarcoid lymph nodes. In lung tissues, macrophages bearing the ICAM-1 antigen were present in sarcoid tissue but not in the interstitium and alveolar space of UIP. LFA-1 (CD11a/CD18) and VLA-4 (CD49d/CD29) were present on all leucocytes found but seemed to be more highly expressed on lymphocytes in sarcoidosis. These findings suggest that the LFA-1/ICAM-1 and VLA-4/VCAM-1 pathways are involved in leucocyte migration in both types of lung disease, while in the active phases of sarcoidosis and UIP, ELAM-1 is also involved.     

EXTEROCEPTIVE STIMULATION AS A CONTINGENT FACTOR IN THE INDUCTION AND ELICITATION OF DELAYED TYPE HYPERSENSITIVITY REACTIONS TO 1 CHLORO-, 2-4, DINITROBENZENE IN GUINEA PIGS

This study attempted to determine whether a prior period of “stress” would elicit the sensitization reaction of the skin to topically applied chemical agents. A subthreshold concentration of 1-chloro-, 2-4, dinitrobenzene (DNCB) was applied to the skin of 40 guinea-pigs, 20 of which had been subjected to repetitive electrical shocks throughout the previous 15 minutes. They were examined 24 hours later, and were retested with DNCB at another site after 9 days for signs of delayed sensitization. The stressed animals exhibited a more severe contact-reaction (p <. 01) after the induction test and also after the delayed test.