Lymphoid tissues of the ileum in young horses: distribution, structure, and epithelium

Lymphoid tissues in the ileum of young horses form raised plaques that are macroscopically visible from the mucosal surface. These are termed ileal lymphoid patches. These patches are variable in size, shape and position within the ileal wall, occasionally lying along the site of mesenteric attachment. Within lymphoid patches, follicles exist in three different morphological forms: follicle/dome structures, proprial follicles, and lymphoglandular complexes (LGCs). In follicle/dome structures, the majority of the follicle lies in the submucosa and merges with a dome in the lamina propria through a gap in the muscularis mucosae. In proprial follicles, the majority, or all, of the follicle is found in the lamina propria, and in LGCs, the follicles lie in the submucosa and communicate with the intestinal lumen via a central invagination of epithelium that extends vertically through a gap in the muscularis mucosae. Follicle-associated epithelium covers the follicle/dome structures and proprial follicles. It consists of enterocytes, cells morphologically resembling M cells, intraepithelial lymphocytes, goblet cells, and amine-precursor uptake and decarboxylation (APUD) cells. The epithelium of LGCs is mainly populated by immature enterocytes, intraepithelial lymphocytes and goblet cells. Cells with coarse, long microvilli are also present. Information regarding the presence of LGCs in the small intestine is scant, but LGCs have been well described in the large intestine of many species. Further investigation will be required to determine if factors exist that are common to both the ileum of the horse and the large intestine of other species to influence the development of LGCs at these specific sites.     

Characterisation of some pharmacological effects of the venom from Vipera lebetina.

Vipera lebetina is one of the most venomous snakes on the Iran plateau. Serious clinical problems such as edema, hemorrhage and tissue necrosis are observed in humans following V. lebetina envenomating. However, little information on the pharmacological properties of the venom is available. To determine haemodynamic actions of the venom of V. lebetina, the changes in the mean arterial blood pressure of anaesthetised rats following the administration of the venom were recorded. Venom (1 mg/kg, i.v.) produced rapid cardiovascular collapse, while 0.3 mg/kg (i.v.) caused only a small transient decrease in mean arterial blood pressure. Effects of the venom on perfusion pressure in the isolated rat mesenteric bed, and on contractions of the isolated rat right atrium and the isolated guinea-pig ileum, were also studied. Exposure of the isolated rat right atrium to venom (0.1-1 mg/ml) caused a transient increase followed by a sustained reduction in the amplitude and frequency of spontaneous contractions. The transient positive inotropic and chronotropic effects were abolished when the preparation was preincubated with propranolol, but not with tolazoline. N(G)-nitro-l-arginine methyl ester pretreatment attenuated the vascular hyporeactivity to phenylephrine induced by the venom in the isolated rat mesenteric vascular bed. This suggests that nitric oxide (NO) or NO-like compounds may be present in the venom and involved in its hypotensive effect. The venom (0.3-1 mg/ml) caused concentration-dependant blockade of isolated guinea-pig ileum contractions induced by electrical field stimulation, acetylcholine or KCl. This inhibitory effect of the venom was significantly reduced by prior incubation of the venom with manoalide (1 microM) indicating involvement of a phospholipase A(2) component. Further, investigation is required to identify specific toxins responsible for the above pharmacological effects.     

全腹腔镜下带血管蒂回肠移植阴道成形术18例临床分析

目的:总结腹腔镜下行带血管蒂回肠移植阴道成形术的方法及临床应用效果。方法:回顾性分析18例全部在腹腔镜下带作的血管蒂回肠移植阴道成形术患者的临床资料。结果:18例手术均获得成功,术后随访3个月至1年半,移植回肠段成活良好,再造阴道符合生理要求;有性生活者14例,均满意。术后不完全肠梗阻1例,经手术及对症处理治愈。结论:腹腔镜下回肠代阴道是目前较为理想的阴道成形方法,腹腔镜下回肠代阴道手术在腹壁上不留手术瘢痕,美容效果理想,但操作难度大,费用较高,可供医患选择。     

Autologous-allotopic ileum mucosa transplantation for small bowel elongation. A morphological study

Introduction Since a standard therapy for short bowel syndrome does not yet exist, every search for new surgical methods would be worthwhile. In previous studies we could show that autologous-allotopic ileum mucosa transplantation is feasible. After a modification of our technique a vascularized colon muscle coat lined completely with transplanted ileum mucosa could be engendered.Method In 12 young beagles autologous ileum mucosa was transplanted in a demucosed vascularized transverse colon segment. The colon coat-ileum mucosa complex was anastomosed with the small bowel immediately after transplantation, 4 weeks later the animals were sacrificed and histology specimens were harvested from the colon coat-ileum mucosa complex, normal ileum and normal colon. After fixation in 2.5% glutaraldehyde the samples were frozen (–40°C) and 14 µm sections were stained with hemalaun and eosin. The lumen diameter, the mucosa, submucosa and colon muscle coat thickness, as well as the mucosal crypt depth were evaluated.Results The diameter of the colon coat-ileum mucosa-complex was smaller than the diameter of normal ileum and colon with no significant stenosis. There were no marked differences in thickness of mucosa and depth of the mucosal crypts compared to the controls, but the transplanted mucosa showed a slightly higher rate of shortened villi. The submucosal layer was thicker following transplantation and showed good neovascularization. The circular muscle layer of the transplanted colon coat was up to 178% thicker and the thickness of the transplanted longitudinal muscle layer differed between 58% and 143% in comparison to normal colon.Conclusions Only a few histologic differences between transplanted and normal ileum mucosa could be observed after autologous-allotopic ileum mucosa transplantation. Therefore a nearly normal function of the colon coat-ileum mucosa complex has to be expected. Long term experiments of the histologic changes as well as further functional studies are on-going in order to finally apply autologous-allotopic ileum mucosa transplantation clinically.     

Contraction of isolated guinea-pig ileum by urotensin II via activation of ganglionic cholinergic neurons and acetylcholine release

Urotensin II and its receptor are expressed in the gastrointestinal tract of mice, but the effects of urotensin II on the gastrointestinal functions have not been established. In the present study, we investigated the effects of human urotensin II on a segment of the guinea-pig ileum. The addition of urotensin II induced contraction of the ileum in concentration-manner (-log EC(50) value was 8.13+/-0.21). The response by urotensin II was extracellular CaCl(2)-dependent and easily desensitized. Like nicotine, the contraction induced by 100 nM urotensin II was inhibited by treatment with atropine, hexamethonium, D-tubocurarine, tetrodotoxin or hemicholinium-3, and enhanced by physostigmine. Treatment with omega-conotoxin GVIA (an inhibitor of N-type Ca(2+) channels, 300 nM) inhibited 100 nM urotensin II- and 4 microM nicotine-, but not 3 microM acetylcholine-, induced contraction. Both urotensin II and nicotine stimulated [(3)H]choline release in a tetrodotoxin-sensitive manner from the prelabeled slices of the ileum. These findings suggest that urotensin II stimulated acetylcholine release from the ganglionic cholinergic neurons and thus stimulated contraction via muscarinic acetylcholine receptors in the guinea-pig ileum. Urotensin II receptor system in the myenteric neurons may regulate the gastrointestinal functions.     

人胎回肠S-100+树突状细胞的免疫组织化学研究

目的：探索人胎回肠树突状细胞的发育规律。方法：应用S—100蛋白抗体SABC免疫组织化学方法对44例6周至38周人胎回肠DC的出现时间、分布部位、形态结构以及数量变化等进行研究。结果：(1)人胎回肠S—100^ DC于第11周出现；(2)S—100^ DC主要分布在粘膜固有层和集合淋巴小结，少数分布在粘膜下层；(3)集合淋巴小结S—100^ DC以滤泡间区数量最多，圆顶区次之，滤泡区少见；(4)固有层S—100^ DC外形不规则，胞体伸出许多粗细不一的突起，而集合淋巴小结S—100^ DC的外形相对规则，突起数量少而细长。结论：人胎回肠S—100^ DC的数量随胎龄的增加而逐渐增加；集合淋巴小结S—100^ DC呈区域性分布，它们与固有层S—100^ DC在形状、大小和数量上有所不同。     

The extracellular space of rat intestine “in vivo”

Summary The extracellular space (ECS) of rat jejunum, ileum and colon were determined in in vivo condition both by means of a continuous perfusion technique and after ligature of the renal pedicles. As a marker, intravenously injected¹⁴C-polyethylenglycol (¹⁴C-PEG) was used.The data indicate that the ECS of rats whose renal pedicles were ligated, increases throughout the experiment, due most probably to a hypertonic expansion of the extracellular space. On the contrary, in the experiments with a continuous perfusion the ECS remains constant throughout the experiment.Total tissue water does not change in the two types of experiments whereas the intracellular water decreases only if the renal pedicles are ligated.     

Malignant fibrous histiocytoma of the ileum

Malignant fibrous histiocytoma occurs most commonly in the extremities and trunk, but rarely in visceral organs. This report documents a case of malignant fibrous histiocytoma arising in the terminal ileum. Following surgical resection, there is no evidence of recurrence or metastasis in this patient after one-year followup studies