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81.
We studied the histological and ultrastructural changes in the liver and alterations in the liver test results before, during, and after treatment with human interferon- from five patients with hepatitis B e antigen-positive chronic active hepatitis. A daily dose of 3×106 to 6×106 units of interferon- was given intravenously for four weeks. The total index of periportal and portal inflammation, intralobular degeneration, and focal necrosis before treatment was decreased significantly six months after treatment (P<0.05). Ultrastructurally, the structure of endoplasmic reticulum was irregularly shaped or fragmentally decreased during treatment, but these disappeared six or 12 months after treatment. Glycogen particles diminished greatly during treatment. The alanine aminotransferase concentrations in these patients increased during treatment. Serum albumin and cholinesterase levels decreased significantly at the fourth week of treatment (P<0.01) and at the third day (P<0.01) to the second week (P<0.05) of treatment, respectively. These results suggest that interferon- injures endoplasmic reticulum and glycogen areas and damages the cholinesterase activity in the early stage of treatment and protein synthesis in patients with hepatitis B e antigen-positive chronic active hepatitis.  相似文献   
82.
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   
83.
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   
84.
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   
85.
Collapsin response mediating protein-2 (CRMP2) has been identified as an intracellular protein mediating Semaphorin3A (Sema3A), a repulsive guidance molecule. In this study, we demonstrate that cyclin-dependent kinase 5 (Cdk5) and glycogen synthase kinase 3beta (GSK3beta) plays a critical role in Sema3A signalling. In In vitro kinase assay, Cdk5 phosphorylated CRMP2 at Ser522, while GSK3beta did not induce any phosphorylation of CRMP2. Phosphorylation by GSK3beta was exclusively observed in Cdk5-phosphorylated CRMP2, but barely in CRMP2T509A. These results indicate that Cdk5 primarily phosphorylates CRMP2 at Ser522 and GSK3beta secondarily phosphorylates at Thr509. The dual-phosphorylated CRMP2, but not non-phosphorylated or single-phosphorylated CRMP2, is recognized with the antibody 3F4, which is highly reactive with the neurofibrillary tangles of Alzheimer's disease. 3F4 recognized the CRMP2 in the wild-type but not cdk5-/- mouse embryonic brain lysates. The phosphorylation of CRMP2 at Ser522 caused reduction of its affinity to tubulin. In dorsal root ganglion neurones, Sema3A stimulation enhanced the levels of the phosphorylated form of CRMP2 detected by 3F4. Over-expression of CRMP2 mutant substituting either Ser522 or Thr509 to Ala attenuates Sema3A-induced growth cone collapse response. These results suggest that the sequential phosphorylation of CRMP is an important process of Sema3A signalling and the same mechanism may have some relevance to the pathological aggregation of the microtubule-associated proteins.  相似文献   
86.
AIMS: p27 is a prominent regulator of cell proliferation by universally inhibiting the cell cycle, while Jun activation domain-binding protein 1 (Jab1), a multifunctional cell signaling protein, contributes to carcinoma progression by degrading p27. In this study, we investigated the expression of these proteins in medullary thyroid carcinoma. METHODS: We immunohistochemically examined Jab1 and p27 expression in 64 medullary thyroid carcinomas. RESULTS: Of the 64 cases examined, decreased p27 expression was observed in 38 cases (59.4%). The p27 expression level was inversely linked to tumour size as well as plasma calcitonin level. Jab1 expression level was generally high, and 46 cases (71.9%) were classified as overexpressing Jab1. The incidence was higher than those in papillary and follicular carcinomas, which were previously reported. Jab1 expression level was inversely linked to that of p27, and all five cases with only cytoplasmic but not nuclear staining of p27 overexpressed Jab1. CONCLUSIONS: These findings suggest that (1) decrease in p27 expression may contribute to local tumour growth; (2) Jab1 expression is related to the progression of medullary carcinoma by decreasing the amount of p27 in the cell and accelerating its degradation; and (3) Jab1 may play a more vital role in the pathogenesis of medullary carcinoma than papillary and follicular carcinomas.  相似文献   
87.
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   
88.
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   
89.
Cell sheet engineering: recreating tissues without biodegradable scaffolds   总被引:6,自引:0,他引:6  
Yang J  Yamato M  Kohno C  Nishimoto A  Sekine H  Fukai F  Okano T 《Biomaterials》2005,26(33):6415-6422
While tissue engineering has long been thought to possess enormous potential, conventional applications using biodegradable scaffolds have limited the field's progress, demonstrating a need for new methods. We have previously developed cell sheet engineering using temperature-responsive culture dishes in order to avoid traditional tissue engineering approaches, and their related shortcomings. Using temperature-responsive dishes, cultured cells can be harvested as intact sheets by simple temperature changes, thereby avoiding the use of proteolytic enzymes. Cell sheet engineering therefore allows for tissue regeneration by either direct transplantation of cell sheets to host tissues or the creation of three-dimensional structures via the layering of individual cell sheets. By avoiding the use of any additional materials such as carrier substrates or scaffolds, the complications associated with traditional tissue engineering approaches such as host inflammatory responses to implanted polymer materials, can be avoided. Cell sheet engineering thus presents several significant advantages and can overcome many of the problems that have previously restricted tissue engineering with biodegradable scaffolds.  相似文献   
90.
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   
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