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71.
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   
72.
This investigation was designed to assess the influence of dynamic cord compression on severity and course of myelopathy. Sixty-seven patients studied comprised 54 cases of cervical spondylosis and 13 cases of ossification of the posterior longitudinal ligament. These patients underwent "dynamic" MR imaging of the cervical spine. MR images in the sagittal view were obtained in three different neck positions: flexion, neutral, and extension. MR imaging was performed with a 0.15 T resistive unit. For technical reasons, the body coil was used. The pulse sequence was 500/30 (Tr msec/echo time msec) for T1 images. The spinal cord compression was accelerated in 32 cases when extended, in 2 cases when flexed, and in 4 cases when both extended and flexed. In 21 cases, we compared myelograms with MR images in a same neck position. Findings of myelograms well corresponded with those of MR images on 83 percent of intervertebral levels. The patients with dynamic cord compression were proved to have severer long tract signs, and their disability was regressive or progressive case by case for an average of 21-month follow-up. The "dynamic" MR imaging can provide dynamic nature of spinal cord compression, and prognostic clues.  相似文献   
73.
Recurrent chromosomal gain at 1q is one of the most common features of human hepatocellular carcinoma (HCC), but how the gain at 1q contributes to hepatocarcinogenesis is still unclear. To identify the target genes, precise determination of the shortest region of overlap (SRO) and of breakpoints is necessary. Similarly, the role of loss at 1p, which is also a major cytogenetic aberration in HCC, needs to be determined. Fifty HCCs were examined with the aid of 59 microsatellite markers distributed throughout both arms of chromosome 1. To detect allelic gain effectively, the cutoff value of the allelic imbalance index was set at 0.70. Alleles showing imbalance were subjected to multiplex PCR, using a retained allele as an internal control, to determine whether the imbalance was the result of chromosomal gain or loss. The SRO of the gains was defined as D1S2878-D1S2619 (1q23.-q25.3, 16.9 Mb), which involved 36 cases (72%). Gains in the number of copies of certain oncogenes within this region seemed to be critical for the pathogenesis of HCC. In contrast, the centromeric breakpoints of these gains varied, but they tended to occur mainly in the pericentromeric region (26 of 50 cases, 52%). Rearrangement of specific genes associated with the gains is unlikely. On the other hand, the SRO of deletion was defined as D1S2893-D1S450 (1p36.32-p36.22, 5.1 Mb). Four known putative tumor-suppressor genes (TP73, RIZ1, NBL1/DAN, and CDKN2C) were outside the SRO, suggesting the presence of other candidate genes with critical roles in hepatocarcinogenesis.  相似文献   
74.
Follicular lymphoma is characterized genetically by t(14;18)(q32;q21), whereas t(18;22)(q21;q11), a rare variant form of t(14;18), has been preferentially observed in chronic lymphocytic leukemia (CLL). We describe here an unusual case of follicular lymphoma with a t(18;22)(q21;q11), that progressed to diffuse large cell lymphoma with a novel t(2;6)(p12;q23). Spectral karyotyping revealed that add(2)(p12) and add(6)(q23) were derived from a t(2;6)(p12;q23). Fluorescence in situ hybridization analysis confirmed rearrangements of the BCL2 gene at 18q21 and the BCL6 gene at 3q27. Our results indicate that a reciprocal translocation involving 6q23 could be implicated in the progression of follicular lymphoma and that t(18;22) may have a specific role in the pathogenesis of follicular lymphoma as well as CLL.  相似文献   
75.
An autopsy case of systemic histiocytosis with excessive deposition of K-type light chain crystals was reported in a 58 year-old man who had consistently showed K-type light chain paraproteinemia, Bence Jones proteinuria and hypogammaglobulinemia for about 10 years until his death. However, no bony destruction was found by repeated X-ray examinations. At autopsy, extensive hyperplasia of crystal-storing histiocytes was observed in the bone marrow, spleen, liver, lymph nodes, interstitial tissues of visceral organs and loose connective tissues. In the bone marrow and some other tissues, mild proliferation of plasmocytoid cells containing small crystals were found, Histochemically the crystals positively stained with various methods for amino acids and proteins, especially with Weigerts'method for fibrin Ultra-structurally intralysosomal crystal deposition was confirmed in the storage histiocytes and derivation of the crystals from Golgi's sacculi in the plasmocytoid cells was suggested. Biochemically the crystals were regarded as mainly consisting of dimers of a variable half of light chain immunoglobulin and immunochemically and immunohistochemically reacted to anti- type light chain serum. Such a generalized storage histiocytosis may be secondarily induced by immunoglobulin synthesized in plasmocytoid cells.  相似文献   
76.
PROBLEM: In order to investigate the role of macrophage colony-stimulating factor (M-CSF) and monocyte chemoattractant protein -1 (MCP-1) in human ovulation, we studied the regulation of M-CSF and MCP-1 in cultured human granulosa cells. METHOD OF STUDY: Immortalized granulosa cells (GC1a) were cultured in serum-free medium, and incubated with interleukin (IL)-1alpha, IL-1 receptor antagonist (ra) and tumor necrosis factor (TNF)-alpha. The supernatants were collected, and M-CSF and MCP-1 were measured by ELISA. RESULTS: The levels of M-CSF and MCP-1 were increased after treatment with IL-1alpha (1 nm) and TNF-alpha (1 nm) in a time-dependent manner. The levels of M-CSF and MCP-1 were significantly increased after treatment with IL-1alpha and TNF-alpha in a dose-dependent manner. However, the levels of M-CSF and MCP-1 were significantly decreased by treatment with IL-1alpha (1 nm) and/or increasing concentrations of IL-1 ra. CONCLUSIONS: Our data indicated that M-CSF and MCP-1 were regulated by IL-1alpha and TNF-alpha. It was suggested that M-CSF and MCP-1 may play an important role in human preovulatory processes.  相似文献   
77.
To investigate the role of thymic nurse cells (TNC) in activation and differentiation of fetal CD4-CD8- (double-negative) thymocytes, we have co-cultured murine fetal thymocytes (14-15 days of gestation) with an established murine TNC clone. We show here that TNC induced the growth of the fetal double-negative thymocytes in the presence of recombinant interleukin 2 (rIL2). Activated fetal thymocytes markedly formed lymphocyte-TNC complexes and proliferated extensively after 5 days in the co-culture. The activated fetal thymocytes in this co-culture condition remained double negative after 10 days in culture. None of them gave rise to phenotypically and functionally competent lymphocytes during this period. TNC alone and the supernatant of TNC had no effect on activation. The presence of both TNC and rIL2 was necessary for the growth of fetal thymocytes in our system. The proliferation of fetal thymocytes was inhibited by a monoclonal antibody against mouse IL2 receptors (IL2R). The fetal thymocytes could be maintained further in this co-culture condition. The prolonged cultivation of fetal thymocytes resulted in the establishment of the fetal thymocyte line and its several clones. CD4 single-positive cells of activated fetal thymocytes first appeared 14 days after the onset of culture and their number increased, whereas CD8+ cells or CD4CD8 double-positive cells were not observed. These results indicate that fetal CD4-CD8- thymocytes underwent phenotypic change after long periods of culture. All established clones of fetal thymocytes are CD4 single positive showing lymphocyte-TNC interactions but do not express CD3 complex. Northern blot analysis detected mRNA for the gamma T cell receptor, but no messages for the delta, alpha or beta T cell receptor. Chemical cross-linking of 125I-labelled IL2 revealed that the 90-kDa band (presumably considered to be the IL2R beta chain) was clearly present in IL2-responsive fetal clones, whereas freshly isolated day 14-15 fetal thymocytes lacked the band. Taken together, TNC might be involved in the differentiation and/or expansion of murine fetal thymocytes by inducing IL2R beta chain, which forms the functional IL2R together with IL2R alpha chain and CD4, one of the T cell accessory molecules, on the cell surface through direct cell-cell interaction.  相似文献   
78.
Helicobacter hepaticus contaminating nonfrozen tumors was transmissible to severe combined immunodeficient (SCID) mice, but the organism in cryopreserved samples was not. This suggests that H. hepaticus has the ability to spread via biomaterials and that freezing-thawing is able to reduce the numbers of organisms to levels insufficient for subcutaneous infection of SCID mice.  相似文献   
79.
The ultrasound examination of the deep vein thrombosis   总被引:2,自引:0,他引:2  
Ultrasonography is very useful for detection of deep vein thrombosis. The purpose of this paper is to show a method for detecting them efficiently by high resolution transducer and color Doppler system. We examined patients in the supine and prone positions. To detect the venous flow easily and differentiate thrombi from simple venous dilatation, some maneuvers are useful; one is pushing the vein area using the transducer on examination, the second is breathing overload, and the last is so-called milking. We can find throombi in the external iliac or femoral veins of patients who have symptoms of lower leg swelling, however, we need to better detect venous thrombi in the lower leg in patients with a history of pulmonary embolism. Because deep venous thrombi are increasing, the role of ultrasound will expand in the future.  相似文献   
80.
In order to clarify the histological and immunohistochemical characteristics of suppurative granuloma in abscess-forming granulomatous lymphadenitis (AGL), and the relation between AGL and cat scratch disease (CSD), 36 cases of AGL were studied. The combined results showed that there were two types of suppurative granulomas. The suppurative granulomas histologically revealed small lymphocytes of predominantly T cell phenotype distributed among the epithelioid histiocytes bordering central necrotic areas in the suppurative granulomas. These suppurative granulomas could be further subdivided into two groups, mainly those with and without the intermingling of large transformed cells of B-cell phenotypes: Type B granuloma with large transformed B cells and Type A without large transformed B cells. Both types of granulomas were observed in a varying degree in most cases. According to the predominant type of granulomas, 36 patients with AGL were further classified into two groups: Group I of Type A dominance and Group II of Type B dominance. Warthin-Starry (WS) silver stain positive bacteria, which are said to be a causative agent of CSD, were present in about 50% of both groups. No Brown-Hopps' Gram-positive bacteria, fungus, toxoplasma, Chlamydia or Bacillus Calmette-Guerin antigen were found in any case. Clinically, there was no significant difference between these two groups. On the other hand, the detection of WS-positive bacteria seemed to have some relationship with the duration of disease and the history of exposure to cats, and 70% of AGL cases occurred in autumn without a single concurrent epidemic.  相似文献   
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