角膜碱烧伤中郎格罕细胞的变化及作用

采用ATP酶染组化技术,结合光镜动态观察了豚鼠角膜碱烧伤中郎格罕细胞(LC)的变化。发现碱烧伤后第4天角膜LC开始增加(中央部42.2±2个/mm~2,周边部120.8±8个/mm~2),11 d达高峰(中央部143.5±4个/mm~2,周边部219.5±11个/mm~2),2周后开始下降(中央部53.5±15个/mm~2,周边部133.7±12个/mm~2)。提示LC是一类在某些因素刺激下可移动的细胞群。并讨论了LC在角膜碱烧伤发病机制和损伤修复中的作用。     

班布特罗对致敏豚鼠肺机械功能的影响

目的：研究β2激动药班布特罗的支气管扩张作用。方法：通过测定致敏豚鼠抗原攻击前后的肺阻力（RL）和肺动态顺应性（Cdyn）变化，观察班布特罗对气道的扩张作用。结果：对照组的致敏豚鼠在抗原攻击后1min即达到反应高峰，RL比攻击前增高205．5％，在攻击后1～15min内（每3min测一次）比攻击前平均增高169．5±44．0％；Cdyn下降52．6％，平均下降50．0±4．2％。班布特罗2．0、5．0和10．0mg／kg组在攻击后1min时，RL值比攻击前分别增高80．6％、27．9％和15．0％，攻击后1～15min内（每3min测一次）比攻击前分别平均增高150．3±64．6％、47．7±18．9％和36．9±19．3％；Cdyn在攻击后1min时分别下降35．5％、16．3％和－1．3％，分别平均下降45．5±7．7％、18．6±4．6％和11．8±11．1％。经统计处理，班布特罗5．0和10．0mg／kg组与对照组比较，差异有显著性（分别为P＜0．05，P＜0．01）。结论：班布特罗（灌胃给药）对豚鼠有较强的气道扩张作用。     

Role of sensory neuropeptides in post-allergic propranolol-induced bronchoconstriction in guinea pigs in vivo

Background Administration of propranolol can provoke bronchoconstriction in asthmatic patients. We hypothesized that such bronchoconstriction may result from the inflammatory mediators released by an allergic reaction. We recently developed a guinea pig model for propranolol-induced bronchoconstriction (PIB). Neuropeptides which are released from C-fibre nerve endings have been postulated to induce bronchial hyperresponsiveness through neurogenic inflammation. Objective The purpose of this study was to examine whether sensory neuropeptides are involved in the development of PIB after allergic reaction. Methods Propranolol at a concentration of 10mg/ml was inhaled 20min after antigen challenge in passively sensitized, anaesthetized and artificially ventilated guinea pigs. The animals were treated intravenously with a NK₁ and NK₂ dual antagonist, FK224, in a dose of 1 or 10 mg/kg or vehicle or a selective NK₁ antagonist, FK888, in a dose of 1 or 10mg/kg or vehicle 10min before or 15min after antigen challenge. Results Propranolol inhaled 20 min after antigen challenge caused bronchoconstriction. FK224 or FK888 administered 15 min after antigen challenge as well as 10 min before antigen challenge did not reduce the PIB. Conclusion We conclude that neuropeptides such as neurokinin A and substance P do not directly contribute to the development of PIB after allergic reaction.     

屠宰猪体内汞含量与食物链相关研究

采用氢化物发生冷原子化法对工业区和农业区饲喂的60头猪的肝、肾、肌肉中有害重金属元素汞含量进行了调查分析,同时也分析了对应的饲料和土壤中汞含量;结果猪体、饲料、土壤中汞含量匀为工业区大于农业区,差异极显著(P<0.01):探讨了汞污染与食物链的关系,并进行了猪体内不同部位系的蓄积性比较、相关性分析及卫生评价。     

Effects of feeding regimen on ethanol intake by guinea pigs

During daily two-hr sessions, guinea pigs licked a drinking tube filled with either 0 (tap water), 2, 4 or 8% (v/v) ethanol solution under three feeding regimens. Consumption of each solution was highest when sufficient food to maintain subjects at 90% of free-feeding weight was provided during sessions, lower when the same food ration was provided after sessions, and lowest when ad lib access to food was provided within and between sessions. However, this decrease in consumption across feeding regimens was inversely related to ethanol concentration. Under all feeding regimens, volume of solution consumed decreased with increasing ethanol concentration while milligrams ethanol consumed increased with ethanol concentration. These results are similar in some respects to previous findings with rats and monkeys, suggesting that further studies of oral ethanol self-administration by guinea pigs may be merited.     

Studies on the role of prostaglandins in the regulation of retinal blood flow

Prostaglandin E₁ was injected close to retinal arterioles by iontophoresis. Vasodilatation apparently similar to that caused by hypercapnia or hypoxia was observed. Inhibitors of prostaglandin synthetase were injected into the circulation. There was a reversible inhibition of the retinal vasodilation normally induced by hypercapnia. It is concluded that prostaglandin E₁ satisfies two criteria for a candidate for a mediator of hypercapnia-induced arteriolar dilatation. The effect of hypoxia appears more complicated.     

Possibility of passive transfer of cold urticaria to guinea pigs

Serum from one out of six patients with idiopathic acquired cold urticaria produced a short lived edematous reaction in the pinna of guinea pigs 24 hours after intradermal injection of the patient's serum and subsequent cold challenge. No relationship was observed between the transfer activity and IgE titer or atopic status.     

Possibility of using guinea pigs for studying the carcinogenic activity of some endogenous substances

The tryptophan metabolites 3-indolylacrylic acid and 2-aminoacetophenone, whose carcinogenic activity has been demonstrated by experiments on inbred mice, were injected into noninbred guinea pigs. Both substances induced tumors in the animals of the exprimental groups earlier than in the control and the tumors differed significantly in their morphology from those in animals of the control groups, evidence that both compounds have a carcinogenic effect. The results indicate that guinea pigs can be used to study the carcinogenic activity of weak carcinogens of the endogenous class.Experimental Animals Division, Oncologic Scientific Center, Academy of medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR L. M. Shabad.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 8, pp. 200–202, August, 1977.     

Cellular, Histomorphologic, and Clinical Characteristics of a New Octyl-2-Cyanoacrylate Skin Adhesive

Short-chained cyanoacrylates have been used for many years for topical skin closure. Toxic effects in cell culture of a new long-chained octyl-2-cyanoacrylate tissue adhesive are compared with those of short-chained ethyl-2- and butyl-2-cyanoacrylates. Two cellular tests were used: the agar overlay test and the MTT test. An in vitro test using copper plates coated with the three types of cyanoacrylates serves for evaluating the stability of polymerized skin adhesives. Bilateral neck skin incisions in Goettingen miniature pigs were glued on one side with Dermabond. On the other side, conventional sutures were applied. After the pigs were killed, the resulting skin samples were tested for the tensile strength of their wound stability. Samples of pig dermis were exemplarily and histomorphologically characterized. A clinical examination after submandibular lymph node dissection should examine the application in humans. Cell culture tests were used to show the toxic effects of the three cyanoacrylates. In a copper test, octyl-2-cyanoacrylate was more stabile than ethyl- and butyl-cyanoacrylates. Breaking strength was 30% lower 28 days after operation with the new product than with sutures. In electron microscopy, octyl-2-cyanoacrylate showed no disadvantages with regard to tissue regeneration and no histotoxicity. For plastic surgery, this new topical skin adhesive is a real alternative with attractive results, as compared with conventional suture.     

Methicillin-resistant Staphylococcus aureus in pig farming

We conducted a study among a group of 26 regional pig farmers to determine the methicillin-resistant Staphylococcus aureus prevalence rate and found it was >760 times greater than the rate of patients admitted to Dutch hospitals. While spa-type t108 is apparently a more widespread clone among pig farmers and their environment, we did find other spa-types.