Mast cell corticotropin-releasing factor subtype 2 suppresses mast cell degranulation and limits the severity of anaphylaxis and stress-induced intestinal permeability

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A small-animal activity-analysing system for behavioural studies

Automated recording and data analysis of the activity of small laboratory animals are often required for psychological and other forms of behavioural investigation. This paper describes such a system using an open field of 1·14×1·14 m. Three arrays of infrared-light-emitting diodes and phototransistors are used to locate the animal. Two of the arrays are used to generate an xy grid, while the third one is used to determine whether the animal is rearing. The position of the animal gives rise to both digital and analogue signals; so the equipment can be interfaced directly with a minicomputer, or coupled to an analogue recorder. Several activity parameters, such as the path length (absolute value of the line integral), the time spent at a predetermined area of the open field or the latency to move, are computed and displayed in digital form.     

Secretory transmembrane potentials in acinar cells from the cat submandibular gland during perfusion with a chloride-free sucrose solution

Summary The cat submandibular gland was perfused with a normal NaCl Locke solution and a chloride-free sucrose solution. The numerical increase in acinar membrane potential (secretory potential) was recorded after intra-arterial injection of acetylcholine.There was no significant difference between the size of the secretory potentials recorded during perfusion with the sucrose solution [23.6 mV±1.4 (n=23)] and the size of those recorded during the control periods [20.6 mV±1.2 (n=24)].The maximal value of the membrane potential after injection of acetylcholine was higher [51.8 mV±2.4 (n=23)] during perfusion with the sucrose solution than during the control periods [44.8 mV±1.8 (n=22)].The results show that a pump transporting chloride into the acinar cells cannot be responsible for the generation of the secretory potentials. The results are best accounted for by assuming that an outward passive transport of potassium, being partly short-circuited by an inward passive sodium transport, is responsible for the change in membrane potential after stimulation with acetylcholine.Supported by the Danish State Research Foundation and Johann and Hanne Weimann's legate.     

高压静电场照射雏鸡免疫器官的细胞免疫变化

目的探讨不同性质高压静电场对雏鸡免疫器官细胞免疫变化的影响。方法用组织化学染色及细胞培养技术和MTT测定法对高压静电场照射雏鸡免疫器官的T细胞数量及其对ConA增殖功能的动态变化进行了检测。结果高压正静电场照射雏鸡免疫器官的T细胞数量及其增殖功能明显高于高压负静电场照射雏鸡和对照雏鸡；而高压负静电场照射雏鸡免疫器官的上述各项检测指标均不同程度的低于对照雏鸡。结论高压正静电场照射对雏鸡免疫器官的细胞免疫功能有促进作用，而高压负静电场照射可使雏鸡免疫器官的细胞免疫功能降低或减弱。     

独立准直器位置精度对半野联合处剂量的影响

目的:介绍在乳腺癌和鼻咽癌放射治疗中的单一等中心半野联合放疗技术,并对独立准直器位置精度对半野联合处剂量的影响进行研究,提出对策.方法:用带独立准直器的直线加速器,以一个等中心,上下半野技术照射体模,用胶片剂量仪分析半野衔接处剂量分布情况,并将研究结果应用于乳腺癌和鼻咽癌病人的放射治疗.结果:受加速器独立准直器位置精度的影响,半野衔接处可能存在最大不超过2mm的过剂量区或欠剂量区.如果消除该系统误差的影响,则半野衔接处可得到均匀的剂量分布.结论:单一等中心半野联合照射,半野衔接处处于照射靶区,必须重视独立准直器位置精度对衔接处剂量的影响,并加以修正.     

Receptive fields of single cells in the cat's superior colliculus

Summary Receptive field analysis of single units in the superior colliculus of the mid-pontine, pretrigeminal cat has confirmed previous reports of directionally selective units in the tectum. The directional property was based principally upon a unilateral inhibitory mechanism, although some directional responses to small moving objects depended equally upon summation of excitation. Receptive field size varied greatly, with field diameters not uncommonly exceeding 30 degrees. Fields near the area centralis and along the horizontal meridian tended to be smaller than those elsewhere. An inhibitory influence from the field periphery was demonstrated.Post-doctoral fellow of the National Science Foundation. Present address: Department of Experimental Psychology, Walter Reed Army Institute of Research, Washington, D. C. 20012 (USA).     

The time-course of ribavirin-provoked changes of basal and AMPH-induced motor activities in rats

The time-course of changes of basal and amphetamine (AMPH)-induced locomotor and stereotypic activities in adult male Wistar rats after a single ribavirin injection was studied. In the first set of experiments, 10, 20 or 30 mg ribavirin/kg body weight (b.w.) were injected i.p. to rats and their basal motor activities were recorded every 10 min for 2 h and compared with those of saline-treated controls. In the second set of experiments, the animals were pretreated with ribavirin and 20 min later i.p. injected with AMPH (1.5 mg/kg b.w.). The controls received AMPH 20 min after the saline injection. Motor activity was recorded after the first injection and until 120 min after AMPH administration. Ribavirin did not significantly affect the time-course of either basal locomotor or stereotypic activities. Pretreatment with any of the applied ribavirin doses decreased the AMPH-induced hyperlocomotor response. However, the most pronounced effect was observed with ribavirin doses of 20 mg/kg and 30 mg/kg when administered during the first 10 min and 30 min after the AMPH injection respectively. In contrast, the stereotypic activities of these animals were only slightly changed. These results indicate a different susceptibility of regions in the basal ganglia to ribavirin.     

Nkx2.5‐negative myocardium of the posterior heart field and its correlation with podoplanin expression in cells from the developing cardiac pacemaking and conduction system

Recent advances in the study of cardiac development have shown the relevance of addition of myocardium to the primary myocardial heart tube. In wild‐type mouse embryos (E9.5–15.5), we have studied the myocardium at the venous pole of the heart using immunohistochemistry and 3D reconstructions of expression patterns of MLC‐2a, Nkx2.5, and podoplanin, a novel coelomic and myocardial marker. Podoplanin‐positive coelomic epithelium was continuous with adjacent podoplanin‐ and MLC‐2a‐positive myocardium that formed a conspicuous band along the left cardinal vein extending through the base of the atrial septum to the posterior myocardium of the atrioventricular canal, the atrioventricular nodal region, and the His‐Purkinje system. Later on, podoplanin expression was also found in the myocardium surrounding the pulmonary vein. On the right side, podoplanin‐positive cells were seen along the right cardinal vein, which during development persisted in the sinoatrial node and part of the venous valves. In the MLC‐2a‐ and podoplanin‐positive myocardium, Nkx2.5 expression was absent in the sinoatrial node and the wall of the cardinal veins. There was a mosaic positivity in the wall of the common pulmonary vein and the atrioventricular conduction system as opposed to the overall Nkx2.5 expression seen in the chamber myocardium. We conclude that we have found podoplanin as a marker that links a novel Nkx2.5‐negative sinus venosus myocardial area, which we refer to as the posterior heart field, with the cardiac conduction system. Anat Rec, 290:115–122, 2007. © 2006 Wiley‐Liss, Inc.     

基于椭圆方程的三维心脏超声图像的位移场估计

三维超声心动图技术能使医生直观地看到心脏整体和各部分的运动，在临床得到重视。在三维超声心动图技术中，如何定量的描述心脏中某个组织的运动状况极具临床意义。本研究提出了一种基于椭圆偏微分方程的二尖瓣三维运动估计方法。该方法直接在三维超声图像的位移场上进行了运动估计，避免了传统运动估计方法，如光流法，需要标定的缺点。本研究首先建立一个二次误差指标函数，然后利用变分法导出了三维空间下的一组椭圆型偏微分方程。这类方程有着比较成熟的数值解法，利用了有限差分法，对多个三维超声数据立方体进行了计算，结果证明这类方法是有效的。     

Effects of floor textures on open-field behavior in selected lines of mice

Mice representing the twenty-second generation of selection for high and low open-field activity were tested on four different floor textures: soil, bedding, metal, and astroturf. Members of both groups were most active on soil and least active on the metal floor surface. Although floor texture significantly affected activity level, rank order of the high and low selected groups was maintained. In general, defecation scores were negatively correlated with activity.