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11.
Syringolides are water-soluble, low-molecular-weight elicitors that trigger defense responses in soybean cultivars carrying the Rpg4 disease-resistance gene but not in rpg4 cultivars. 125I-syringolide 1 previously was shown to bind to a soluble protein(s) in extracts from soybean leaves. A 34-kDa protein that accounted for 125I-syringolide 1 binding activity was isolated with a syringolide affinity-gel column. Partial sequences of internal peptides of the 34-kDa protein were identical to P34, a previously described soybean seed allergen. In soybean seeds, P34 is processed from a 46-kDa precursor protein and was shown to have homology with thiol proteases. P34 is a moderately abundant protein in soybean seeds and cotyledons but its level in leaves is low. cDNAs encoding 46-, 34-, and 32-kDa forms of the soybean protein were cloned into the baculovirus vector, pVL1392, and expressed in insect cells. The resulting 32- and 34-kDa proteins, but not the 46-kDa protein, exhibited ligand-specific 125I-syringolide binding activity. These results suggest that P34 may be the receptor that mediates syringolide signaling.  相似文献   
12.
Summary This report presents a variant of Gerstmann-Sträussler syndrome (GSS). A 53-year-old female had developed slowly progressive dementia and atactic gait since the age of 45. No myoclonic jerks and periodic synchronous discharges were observed throughout the illness. The neuropathological study revealed that many amyloid plaques and widespread Alzheimer's neurofibrillary tangles (NFTs) appeared in the cerebral cortex. Characteristically, the plaques reacted with anti-prion protein and none of them reacted with anti- protein, and they were made of many components, including amyloid cores, macrophages laden with lipid granules and/or degenerated neurites. Neuropil threads were seen mainly in amyloid plaques. Moreover, plaques appeared which were confluent and laminar in arrangement in the fifth and sixth cortical layers and had a close relationship to the neuronal loss. There was no spongiform change in the cerebral cortex or cerebellum. The cerebellum was almost intact except for a few amyloid plaques. Ultrastructurally, some of the plaques simulated kuru plaques and others had many degenerated neurites possessing paired helical filaments and other accumulated organelles. GSS has been proposed to include cases with progressive ataxia, dementia and massive multifocal plaques in the brain with or without cerebral spongiform changes. The case presented here is a very peculiar case of GSS. Recently, similar cases have been reported in some large families, diagnosed as familial Alzheimer's disease. These cases may be a telencephalic form with numerous NFTs of GSS.  相似文献   
13.
Chromophobe renal cell carcinoma (RCC) is a recently established subtype of RCC, which has rarely been reported in Japan. In this communication, the authors report two Japanese cases of chromophobe RCC together with the immunohistochemical findings. The tumors were composed of sheets and cribriform glands formed by tumor cells with cloudy and reticular cytoplasm. Ultrastructurally, the cytoplasm was filled with numerous microvesicles. The tumor cells were positive for cytokeratin, epithelial membrane antigen, and Tamm-Horsfall protein. Occasionally, LeuM1-positive cells were also noted. Vimentin was negative, unlike the usual RCC. Reactivity for peanut agglutinin was more frequent than that to Lotus tetragonolobus agglutinin. The results of this study suggest that the tumor cellq possessed phenotypes similar to the distal nephron rather than to the proximal tubular cells.  相似文献   
14.
Yamamoto Y  Sefton MV 《Biomaterials》2003,24(3):435-442
Tresylation of an amine containing polymer film in the presence of PC12 cells did not result in a significant loss of cell viability, at least as assessed by trypan blue exclusion or MTT assay. PC12 cells were cultured atop reactive poly(acrylamide-co-vinyl amine) films or tissue culture polystyrene and exposed for 2 h to tresylated polyethylene glycol (TPEG) or unreactive hydrolyzed TPEG in 0.1M TES (N-tris hydroxymethyl-2-aminoethane sulfonic acid). The loss in trypan blue viability was limited ( approximately 80% retained), provided the TPEG concentration was 10 micromol/g or less. Similarly when microencapsulated PC12 cells (in a non-reactive polyacrylate hydrogel) were exposed to TPEG (10 micromol/g in 0.1M TES) the loss of MTT activity was small. The loss of vaibility was attributed to the toxicity of the tresyl leaving group and not the reaction itself. Thus, it may be possible to surface modify cell containing microcapsules, at least under limited conditions, in order to improve their biocompatibility without compromising the viability of the enclosed cells. This should lead to the development of new (reactive) polymers for microencapsulation since biocompatibility need not be a design consideration in the first instance.  相似文献   
15.
Two human ovarian adenocarcinoma cell lines, MCAS-3 and OVISE-3 were found to secrete little of any type of gelatinase in tissue culture. However, when these cell lines were implanted subcutaneously into nude mice the cyst fluids from the resultant tumors contained gelatinase A and/or B. The enzyme activities, especially of gelatinase B, were much higher in the malignant MCAS-3 tumors than in those of the less malignant OVISE-3 tumor cells. To elucidate the origin of gelatinase B in cyst fluids of the MCAS-3 tumors, murine skin fibroblasts (MSF) were isolated from a subcutaneous tumor in a nude mouse and tested for their proteinase secretion in culture. MSF cells, which secreted some gelatinase A and gelatinase B, were induced to secrete high levels of both enzymes, especially gelatinase B, by co-cultivation with MCAS-3 cells. In addition, gelatinase A activity was induced by incubation of MSF cells with the conditioned medium of either MCAS-3 or OVISE-3 cells, whereas gelatinase B was induced only with that of MCAS-3. Although cytokines or growth factors such as IL-1 TGF-1, TNF- or EGF stimulated the secretion of gelatinases A and B from MSF cells, their effects on gelatinase B activity were far less than that of the MCAS-3 conditioned medium. These results indicate that the major part of gelatinase B activity in the cyst fluids of the ovarian tumors is secreted by host interstitial cells stimulated by tumor-derived humoral factors. Similar tumor cell-host cell interactions may be important in the production of various proteinases in other tumor types.  相似文献   
16.
Summary Two cases of renal epithelial tumours are reported in females aged 46 and 66 years respectively. In spite of the large size of the tumours, neither invasive growth nor metastasis was observed. Histologically, the tumours were composed of immature epithelial cells forming tubules with abortive glomeruloid structures. Electron microscopy of tumour cells revealed poorly developed polarity and intracytoplasmic organelles. They showed similar immunohistochemical reactions to those of developing nephrons, particularly to those of the S-shaped body. The nuclear DNA content of the tumour cells was almost euploid. We conclude that the lesions were epithelial tumours of the kidney histologically mimicking developing renal parenchyma.  相似文献   
17.
Summary Experimental contraction was produced in the rat mesenteric arteries and the arterial segments were studied morphologically. When the rat mesenteric artery was exposed in physiological saline solution at 37° C and 2–3 mg of methoxamine hydrochloride (10 mg/ml) was dripped onto it, intense contraction was observed for about 30 min but elevation in blood pressure was slight. During the contraction, numerous vacuoles were seen in the medial smooth muscle cells of the arterial segments, and these vacuoles were shown electron microscopically to have double unit membranes, indicating that they were formed by herniation of a part of the adjacent smooth muscle cell body. In the arteries 1–6 h after the end of the contraction, cellular, nuclear and vacuolar membranes and myofilaments of the medial muscle cells were partially lost. 12–24 h after the contraction the arteries exhibited necrosis and desquamation of endothelial cells and platelet adhesion. In the media, smooth muscle cells were completely deprived of cell membranes, myofilaments, nuclei, intracytoplasmic organelles other than mitochondria, and vacuolar membranes. The cytoplasm was filled with fine granular and granulo-vesicular material, and fibrin insudation was observed in these severely damaged cells. Arterial contraction may be an important factor in the induction of arterial lesions.  相似文献   
18.
Malnutrition negatively affects the quality of life of patients with dysphagia. Despite the need for nutritional status assessment in patients with dysphagia, standard, effective nutritional assessments are not yet available, and the identification of optimal nutritional assessment items for patients with dysphagia is inadequate. We conducted a scoping review of the use of nutritional assessment items in adult patients with oropharyngeal and esophageal dysphagia. The MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials databases were searched to identify articles published in English within the last 30 years. Twenty-two studies met the inclusion criteria. Seven nutritional assessment categories were identified: body mass index (BMI), nutritional screening tool, anthropometric measurements, body composition, dietary assessment, blood biomarkers, and other. BMI and albumin were more commonly assessed in adults. The Global Leadership Initiative on Malnutrition (GLIM), defining new diagnostic criteria for malnutrition, includes the categories of BMI, nutritional screening tool, anthropometric measurements, body composition, and dietary assessment as its required components, but not the blood biomarkers and the “other” categories. We recommend assessing nutritional status, including GLIM criteria, in adult patients with dysphagia. This would standardize nutritional assessments in patients with dysphagia and allow future global comparisons of the prevalence and outcomes of malnutrition, as well as of appropriate interventions.  相似文献   
19.
Clinical and Experimental Nephrology - The data regarding oncological outcome in advanced renal cell carcinoma (RCC) arising in end-stage renal disease (ESRD) are limited. Patients diagnosed with...  相似文献   
20.

Purpose

The present study was designed to examine the antinociceptive effects of orally administered ONO-9902, an enkephalinase inhibitor, on both somatic and visceral pain after visceral stress conditions.

Methods

Twenty six male rats were examined. Tail-flick (TF) and colorectal distension (CD) tests were used to determine somatic and visceral antinociceptive effects, respectively. Measurements were performed in rats under immediate post-stress conditions (group ST; n = 14) and in rats nor under stress conditions (group NST; n = 12). In the stressed group, the same device, CD, for visceral antinociceptive effects was used for visceral stress and was applied with an intracolonic pressure of 60 mmHg for 20 min after drug administration. The TF latency and CD threshold were measured before and at 30, 40, 50, 60 and 90 min after administration of ONO-9902 300 mg · kg?1 or distilled water.

Results

Orally administered ONO-9902 did not produce any changes in the % maximum possible effect (%MPE) in either TF or CD tests in the unstressed group. In the stressed group, %MPE in the CD test increased 18% and 31% at 30 and 40 min, respectively, after oral administration of ONO-9902 compared with the control group (P < 0.05). However, %MPE to TF test did not alter even after the CD-induced stress condition.

Conclusion

These results suggest that ONO-9902 may have analgesic effects on visceral pain but not on somatic pain under immediate post-stress conditions.  相似文献   
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