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11.
Summary Ghost tangles, neurofibrillary tangles (NFTs) emerging into extracellular space, appear to be subjected to some microglial association in addition to an invasion of astrocytic processes. Our findings lead us to speculate that the NFTs undergo structural and immunocytochemical modification. Electron microscopic observation of the NFTs in the vascular region indicated either the discharge of NFTs into the vessel or formation of NFTs in the astrocytic end-foot.  相似文献   
12.
A 30-year-old female received a head injury at the age of 22 years. Subsequently neurological and psychiatric symptoms, such as personality change, urinary incontinence, dementia and gait disturbance developed. On admission, her cognitive function was severely impaired. Brain CT disclosed cerebral atrophy, dilatation of the lateral ventricle and calcification of the basal ganglia. Pathologically membranous structures were recognized in bone marrow. On the basis of these clinical findings, a diagnosis of Nasu-Hakola's disease was made. In this case, a T2-weighted MRI finding of reduced signal intensity in the thalamus and putamen was characteristic. This finding may be related to intracranial calcification.  相似文献   
13.
Effects of repeated exposure to Fenitrothion (Sumithion) powder on erythrocyte membrane acetylcholinesterase (AChE) and plasma cholinesterase (PChE) were studied. Rats (Wistar, male) were exposed to fenitrothion powder for 2 hrs/day, 5 days/week for up to 3 months. The suppression of AChE and PChE increased as the exposure period and exposure concentration increased, although no suppression of AChE was found after a single 4-hr exposure. The persistence of AChE inhibition after the termination of exposure increased with the increase of the exposure period and was longer than that of PChE. Therefore, the AChE activity seems to be useful in examining the response to the repeated exposure to fenitrothion powder.  相似文献   
14.
15.
Use of a motion-compensated micropipette holder, which senses cardiac motion and lifts and lowers the micropipette and supporting apparatus in synchrony with the heart beat, allows for stable recording of transmembrane action potentials from subepicardial cells of an in vivo beating heart in an open-chest dog without significantly impairing cardiac hemodynamics. This technique may be used to study the effects of ischemia, hypertrophy, or pharmacologic agents on the cellular electrophysiological parameters of subepicardial ventricular cells of an in vivo beating heart.  相似文献   
16.
Several strains that were resistant to the bactericidal action of antibody and complement were isolated from Escherichia coli K-12 W3110/SM by selecting them through the medium containing antiserum and complement. They can be agglutinated by antiserum against the parent strain and showed similar immune adherence reactivity to the parent when sensitized with this antiserum. Few differences were found in the compositions of phospholipids and proteins between both inner and outer membranes of these strains and those of the parent. However, there were fewer short-chain and more long-chain fatty acids in these strains than in the parent. It was also found that unsaturated fatty acide decreased and saturated and cyclopropanoic acids increased in phosphatidylethanolamine and phosphatidylglycerol in both inner and outer membranes of one of these strains when compared with those from the parent. Therefore, the resistance of these strains to the complement-mediated bactericidal action was considered to be due to the rigidity of their membrane structures which might repel the insertion of membrane-attack complement complex C5b-9, although they could fix the earlier complement components up to the step of the formation of C4b,2a,3b complex enzyme.  相似文献   
17.
We encountered a patient who developed an overlap syndrome of progressive systemic sclerosis (PSS), systemic lupus erythematosus (SLE), polymyositis (PM) and Sj?gren's syndrome (SjS) while we were treating her for mixed connective tissue disease (MCTD). This 42-year-old woman had been photosensitive since 18 years of age. In 1986, Raynaud's phenomenon, swollen hands and arthralgia appeared; therefore, we started to treat this patient based on a diagnosis of MCTD. At that time, her anti-RNP antibody titer was 82,920, but she was negative to anti-Sm antibody. In 1988, she was admitted to our hospital with chief complaints of aggravation of polyarthralgia and myalgia. On physical examination, she showed difficulty in opening her mouth, systemic dermal sclerosis, a decrease in muscular strength and rales. In laboratory tests, her myogenic enzyme level was increased, and she was found to be positive to LE cells, antinuclear antibody, anti-DNA antibody, anti-ENA antibody and anti-SSA antibody. Furthermore, histological features clearly corresponding to those of PSS were found by skin biopsy, myogenic changes by electromyography, evidence of chronic inflammation of the salivary glands by lip biopsy, and proliferative changes in the mesangium were detected by renal biopsy. The concept of MCTD, especially the differences from overlap syndrome, is vague. Therefore we need further study about many cases. Since there have been no reports on cases having sufficient evidence of the development of the overlap syndrome of PSS, SLE, PM and SjS during a course of MCTD, our patient would provide very useful data contributing to the study of MCTD.  相似文献   
18.
Defensins are cationic antimicrobial peptides with a broad spectrum. Recently human beta-defensin 2 (hBD-2) has been isolated from psoriatic skin; however, its exact localization and fate have not been fully understood. We studied the distribution pattern of hBD-2 in skin tissues of psoriasis and other inflammatory skin diseases. In the upper spinous and granular layer of psoriasis vulgaris hBD-2 was present in the cytoplasm. In the horny layer the positive signals were in a basket-weave pattern, indicating possible accumulation of hBD-2 in the intercellular space. The similar pattern of hBD-2 distribution was observed in the lesions of nummular eczema and atopic dermatitis. hBD-2 was not detected in the section of normal elbow and knee skin. When isolated psoriatic scales were stained, hBD-2 was detected in a wrapping paper-like distribution pattern surrounding the corneocytes. In horny layer of psoriatic skin hBD-2 was closely associated or colocalized with elafin, which is known to be in extracellular space, as demonstrated by double staining. Western blot analysis using cultured human keratinocytes detected hBD-2 with an expected size in the conditioned medium and in the cell lysates when stimulated with 5% FCS or IL-alpha. These results indicate that hBD-2 was synthesized and remained in cytoplasm in the upper spinous and granular layer, and then secreted into intercellular space in the horny layer. This dynamic change in hBD-2 distribution in epidermis is certainly relevant to function as an innate host defense mechanism against invading micro-organisms.  相似文献   
19.
Seventy-two cases of idiopathic pulmonary fibrosis (IPF) were examined from 2856 consecutive autopsy cases at the Japanese Red Cross Medical Center in Tokyo from 1973-1996. Primary lung cancer had arisen in 31 of 72 cases of IPF (43%), significantly higher than the incidence in cases without IPF (8.1%) and in the cases with non-IPF chronic lung diseases (11.9%). Hyperplastic epithelial foci in the honeycomb lesions of IPF cases were significantly more prominent in the lower than in the upper lobe, in cases with or without lung cancer, and they were more prominent in the lower lobe of IPF with than in those without cancer. The length of hyperplastic epithelial foci in the lower lobe of IPF cases was longer than that in interstitial pneumonia-associated with collagen vascular diseases. There was a higher PCNA labeling index of hyperplastic epithelial foci in IPF cases than in cases of interstitial pneumonia-associated with collagen vascular diseases. The PCNA labeling index was almost the same between smokers and nonsmokers with IPF. Overexpression of p53 was observed in hyperplastic epithelial foci in honeycomb lesion of IPF. DNA ploidy analysis of hyperplastic epithelial foci in the paraffin sections of 12 IPF cases revealed aneuploidy patterns in eight cases. These results strongly suggest that accelerated cell proliferation occurs in the honeycomb lesion of IPF, and that regenerative epithelia becomes susceptible to carcinogenic agents in addition to the smoking effect.  相似文献   
20.
BACKGROUND: Helper T cells are involved in chronic eosinophilic inflammation. Control of cytokine production seems to be an effective management. METHODS: The effect of nonactin, SB203580, a p38 MAP kinase inhibitor, and JTE-711 on the cytokine production of allergen-specific T cell clones was determined. The effect of nonactin on the airway eosinophilia was investigated using murine asthma model. RESULTS: Nonactin suppressed IL-5 synthesis by human Th cells in a dose-dependent manner without affecting IL-2 or IL-4 synthesis, and still significantly suppressed murine airway eosinophilia induced by the antigen inhalation. SB203580 and JTE-711 also selectively inhibited IL-5 synthesis in vitro. CONCLUSION: Synthesis of IL-5 by human Th cells can be differentially regulated from that of other major T cell cytokines. The in vivo effects of selective IL-5 synthesis inhibitors suggest that IL-5 is the reasonable target for the regulation of allergic disorders accompanied by eosinophilic inflammation.  相似文献   
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