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101.
PURPOSE: To investigate the distribution of amino acids (glutamate, aspartate, glutamine, GABA, glycine) in detached retinas with minimum postmortem artifact and to clarify the relation between amino acid distribution and histopathological change in the outer portion of detached retinas. METHODS: Unilateral retinal detachment was produced in cats by injecting 0.25% sodium hyaluronate into the subretinal space using a glass micropipet. The eyes were fixed by perfusion for 10 min, 1, 3, 6 and 24 h, 2, 3 and 7 days after detachment and then examined under conventional light- and electron-microscopic immunocytochemistry. RESULTS: For glutamate, aspartate and glutamine, the inner segments and perikarya of the photoreceptor cells, which were not immunopositive in the normal retinas, showed various degrees of immunoreactivity immediately after retinal detachment. Photoreceptor cells with the strong immunoreactivity developed necrosis. The staining pattern of GABA and glycine scarcely changed during the course of retinal detachment. CONCLUSIONS: Excess intracellular glutamate, aspartate and glutamine in photoreceptor cells may cause a part of neuronal death after retinal detachment.  相似文献   
102.
Phenotypes of isolates of Pseudomonas aeruginosa in a diabetes care center   总被引:1,自引:0,他引:1  
BACKGROUND: Pseudomonas aeruginosa is an invasive organism that frequently causes severe tissue damage in diabetic foot ulcers. A major problem in P. aeruginosa infection may be that this pathogen exhibits a high degree of resistance to a broad spectrum of antibiotics. Some researchers feel that P. aeruginosa is a homogeneous species, whereas others have suggested that they are panmictic. Here we characterized P. aeruginosa populations isolated from diabetic foot ulcer and from hospital environment specimens, both from a tertiary diabetes care center in Chennai, India. METHODS: Phenotypic methods like antibiotic susceptibility determinations using Kirby-Bauer's disc diffusion test and minimum inhibitory concentration (MIC) as well as outer membrane protein SDS-PAGE analysis of P. aeruginosa were performed. RESULTS: Twenty three isolates (29.8%) of P. aeruginosa from 77 diabetic foot ulcers and two environmental isolates (13.3%) from 15 different hospital fomites were detected. Both environmental isolates were sensitive to antibiotics than those isolated from clinical specimens by Kirby-Bauer's disk-diffusion method, which correlated the resistance levels by MIC determination. Outer membrane proteins (OMP) corresponding to 21, 23, 43, 46, 50, and 70 kDa were detected. CONCLUSIONS: The study is captivative as the resistance in P. aeruginosa from diabetic foot ulcers seems very common and because all the isolates were resistant to at least one or more antibiotics tested. Disk-diffusion and MIC results shows that piperacillin, amikacin and imipenem retain high levels of antipseudomonal activities and amikacin two times more active than the aforementioned antibiotics to enable itself as a potent antipseudomonal agent in diabetic foot infections. The OMP profile has revealed that clinical isolates were different from hospital environment isolates, which suggests that the origin of infections by P. aeruginosa is mainly due to growth of bacterial strains acquired by patients prior to hospital admission.  相似文献   
103.

Background  

Postoperative pancreatic fistula (POPF) remains a leading cause of morbidity after pancreaticoduodenectomy (PD). In the present study we sought to establish a preoperative scoring system with which to predict this complication.  相似文献   
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Background and aim  Narrow band imaging (NBI) is a novel endoscopy system, which enables a clear visualization of the mucosal vasculature of the gastrointestinal tract. The aim of this study is to determine whether this system may be of value for assessing the disease severity in ulcerative colitis (UC). Materials and methods  We observed the mucosal vascular pattern (MVP) in 157 colorectal segments of 30 patients with UC using both conventional and NBI colonoscopy. The MVP was determined to be normal or distorted under conventional colonoscopy and, subsequently, to be clear or obscure under NBI colonoscopy. The histologic variables in each segment were assessed in biopsy specimen. The possible correlation between MVP and the histologic grade of inflammation was evaluated. Results  The MVP under conventional colonoscopy was normal in 60 segments while it was distorted in 97 segments. In all of the former 60 segments, their MVP was clear under NBI colonoscopy. The MVP in the latter 97 segments were determined to be clear (n = 44) or obscure (n = 53) under NBI colonoscopy. Acute inflammatory cell infiltrates (26% vs. 0%, p = 0.0001), goblet cell depletion (32% vs. 5%, p = 0.0006), and basal plasmacytosis (2% vs. 21%, p = 0.006) were more frequently observed in segments with an obscure MVP than in those with a clear MVP. Conclusion  NBI colonoscopy may be of value for determining the grade of inflammation in patients with quiescent UC.  相似文献   
107.
We report a new system for monitoring sensations of many body parts as well as comprehensively showing the distribution of overall skin temperature (T(sk)) and temperature-related sensations. The system consists of a console with 52 levers to report temperature-related sensations and software that facilitates the visualization of the distribution of T(sk) and temperature-related sensations by displaying them on a model of the human body. The system's utility was demonstrated with a physiological experiment involving three males and three females. They were exposed to step changes of ambient temperature from 23 degrees C to 33 degrees C. We measured T(sk) at 50 points, and the subjects concurrently provided estimates of local temperature sensation and thermal comfort/discomfort at 25 loci. This system greatly facilitates the perception and analysis of spatial relationships and differences in temperature and sensation in various areas of the body.  相似文献   
108.
We evaluated the effects of a 0.5% cholesterol-enriched diet (HCD) on nitric-oxide synthase (NOS) and arginase expression and the modulating role of 17beta-estradiol (E(2)) on this phenomenon. Thirty oopherectomized rabbits were divided into three groups and treated for 15 weeks. Group I received normal chow; group II, HCD; and group III, HCD plus E(2) pellets. Animals in group II showed an increase in plasma lipids, and they demonstrated atheromatous lesions as well as expression of arginase I and II accompanied by a significant number of BrdU-positive cells in endothelial cells and intimal muscle cells, suggestive of an increase in cellular proliferation. There was significant expression of inducible NOS and increased staining of nitrotyrosine-positive areas. These were not observed in group I animals. In both groups, E(2) levels were low. In group III animals, E(2) supplementation led to a decrease in atheromatous lesions and BrdU-positive cells and reduced expression of both inducible NOS and arginase I and II accompanied by a decrease in nitrotyrosine staining. E(2) levels were increased. Our results suggest that E(2) was responsible for these effects, despite the animals being hyperlipidemic, similar to those in group II. Because arginase is responsible for cell proliferation by converting l-arginine to polyamines, our results indicate that expression of arginase may play an important role in cellular proliferation in atherosclerosis, and inhibition of arginase expression by E(2) may be another potential mechanism in attenuating atherogenesis.  相似文献   
109.
Chronic nonspecific multiple ulcers of the small intestine (CNSU) and nonsteroidal anti-inflammatory drug-induced enteropathy (NSAID-enteropathy) share common clinicopathologic features characterized by histologically nonspecific ulcers and persistent blood loss. The aim was to compare enteroscopic findings between CNSU and NSAID-enteropathy. Four patients with CNSU and five patients with NSAID-enteropathy were examined by enteroscopies. The site of involvement was heterogeneous in NSAID-enteropathy, while the ileum was the predominant site in CNSU. Three patients with NSAID-enteropathy and all four patients with CNSU had concentric stenosis. Circular ulcers were found in all five patients with NSAID-enteropathy and in three patients with CNSU. Active ulcer was seen in only two patients with NSAID-enteropathy. In contrast, all four patients with CNSU had active ulcer. These findings suggest that in patients with persistent GI bleeding and enteroscopically active small intestinal ulcers, CNSU, as well as NSAID-enteropathy, should be considered.  相似文献   
110.
Background: Previous reports have shown that heat-shock protein 70 (HSP70) may be associated with Crohn disease. However, genetic analysis of the HSP70 gene in Crohn disease has not been done. The aim of this study is to investigate whether HSP70-2 gene polymorphism is involved in susceptibility to Crohn disease in the Japanese population and whether it correlates with clinical manifestation of the disease. Methods: A total of 108 genetically unrelated patients with Crohn disease and 108 healthy controls were typed for HSP70-2 PstI polymorphism by restriction fragment length polymorphism analysis (alleles A and B). Patients with Crohn disease were classified into two types: either perforating or non-perforating. Results: Genotype and allele frequency did not differ between patients and controls. In patients with Crohn disease, allele A frequency was significantly higher in the non-perforating than in the perforating type (P = 0.02). When patients with Crohn disease of more than 6.7 years' duration were assessed, the differences in genotype and allele frequency between the two groups became more significant (P < 0.001 and P < 0.001, respectively). Conclusions: These data suggest that HSP70-2 gene polymorphic allele A is a possible genetic marker of less severe clinical phenotype in Japanese patients with Crohn disease.  相似文献   
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