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91.
Cases of proliferative myositis and fasciitis were studied immunohisto-chemically and ultra structurally for further understanding of the nature of ganglion cell-like giant cells. Blood coagulation factor XIIIa, fibronectin, myoglobin, myosin, CPK MM, and alpha-1-antichymotrypsin were detected in three cases of proliferative myositis and two cases of proliferative fasciitis by the avid in-biotin-peroxidase complex method. Factor XIIIa (a fibrin-stabilizing factor) and flbronectin were strongly positive in the giant cells, but not in striated muscle fibers. A small quantity of myosin was demonstrated in the giant cells, but myoglobin and CPK MM were never demonstrated in these cells. No alpha-1-antichymotrypsin was demonstrated in the giant cells. One case of proliferative myositis showed ultrastructural features suggestive of fibroblast rather than muscle cell or histiocytic origin. Strongly positive factor XIIIa in the giant cells is suggestive of the fact that they are active fibroblasts.  相似文献   
92.
It is generally accepted that phosphorylation plays a pivotal role in the cellular response of cell differentiation and proliferation. Immunohistochemical expression of classical protein kinase C (cPKC) subspecies (alpha, beta and gamma) in eight reactive lymphoid tissues, three normal spleens and 149 non-Hodgkin's lymphomas was examined. cPKC beta was observed primarily in the mantle zone B cells, but appeared as very faint staining in Ki-67 positive proliferated B cells in the germinal centers of secondary lymph follicles. In contrast to the reactive state, high levels of cPKC subspecies were recognized in the majority of 149 cases of non-Hodgkin's lymphoma, including those thought to have arisen from germinal center cells such as follicular lymphoma. The expression of cPKC alpha was found in higher frequency in T cell lymphomas than B cell lymphomas (P < 0.01) by the Chi-squared test. High levels of cPKC alpha were present only in high grade or highly aggressive lymphomas, showing the highest incidence in the small non-cleaved cell type, according to the International Working Formulation and National Cancer Institute (P < 0.01). cPKC gamma was not detected in normal lymphoid cells and was expressed in only four cases of non-Hodgkin's lymphomas. It is presumed that cPKC alpha and beta have a relationship to cell activation and proliferation of lymphoid cells of reactive and neoplastic states. It might be considered that the expression of cPKC alpha may have a relationship with aggressiveness in non-Hodgkin's lymphomas.  相似文献   
93.
In human immunodeficiency virus (HIV) infection, CD4 cell counts are useful in defining the disease state, monitoring antiviral treatment, and identifying patients at risk for opportunistic infections. Counting CD4 cells typically relies on traditional immuno-flow cytometric analyzers that require opening the tube for manipulation of the blood sample. In addition to automated blood cell counting, the CELL-DYN 4000 hematology analyzer performs a completely enclosed and automated analysis of the T lymphocyte subsets. We studied the performance characteristics of this method in blood samples containing low levels of CD4+ T cells. In one set of experiments, we emulated low level CD4 counts by use of a CD4 Positive Isolation Kit to deplete the CD4+ cells from blood samples. We used the FACScan analyzer for reference counts. Measurements were made exactly 12 hr after venepuncture in samples that were stored at room temperature. In normal samples and those with low CD4+ cell counts, there was excellent correlation between the results of the CELL-DYN and FACScan methods. Using the CELL-DYN 4000 analyzer, the precision of CD4+ and CD8+ T-cell counts was high (CV = 2 to 8%). The CD4+ T-cell count was linear over a wide range (35 to 1640 cells/microl). This study shows that CD4 and CD8 T cell counts using the CELL-DYN 4000 analyzer is suitable for normal samples and also for those with low CD4+ T cell counts. The method is rapid and automated, and blood specimens remain enclosed, minimizing the biohazard of exposure to blood of HIV patients.  相似文献   
94.
95.
The tumor promoter 12-O -tetradecanoylphorbol-13-acetate (TPA) induces DNA synthesis in quiescent 3T3-L1 cells but not in its variant VT-1 cells. A gt10 cDNA library was constructed using poly(A)+ RNA from 3T3-L1 cells that were stimulated by TPA for 20 min. Radioactive cDNA probes were prepared from mRNAs of TPA-treated 3 T3-L1 and VT-1 cells and used for screening of the 3T3-L1 cDNA library by differential hybridization. Nine of 6000 phage plaques hybridized only to the 3T3-L1 cDNA probe. Analysis of the nucleotide sequence of five of these clones indicated a high degree of homology with human or mouse type I and type III collagen genes. Three other independent clones showed no homology with any known DNA sequences. These isolated clones of TPA-inducible early (TIE) genes may be useful to study the signal transduction pathway of phorbol esters.  相似文献   
96.
97.
An interleukin (IL)-4 dependant mouse T cell clone 8.2 derived from an IL-2-dependent T cell line was characterized. As measured by flow cytometric analysis and Northern blotting, it expresses IL-2 receptor β (IL-2Rβ) and γ (IL-2Rγ) chains, but has lost expression of IL-2 receptor α chain (IL-2Rα). To investigate the properties of the mouse IL-2Rβγ complex and the role of IL-2Rα gene expression, this clone was further studied. T cell clone 8.2 has lost the capacity to bind 125I-labeled human IL-2 under experimental conditions able to detect intermediate-affinity IL-2R in human cells. Mouse IL-2 is unable to block the binding of mAb TMβ1 to 8.2 cells. Under the same experimental conditions, mouse IL-2 blocks the binding of TMβ1 to C30-1 cells expressing the IL-2αβγ complex. Since TMβ1 recognizes an epitope related to the IL-2 binding site of IL-2Rβ, these results can be taken as a demonstration that mouse IL-2Rβγ does not bind mouse IL-2. Furthermore, T cell clone 8.2 does not proliferate in response to recombinant mouse or human IL-2. On the other hand, T cell transfectant lines expressing heterospecific receptors made of the human IL-2Rβ and mouse IL-2Rγ chains bind 125I-labeled human IL-2 and proliferate in response to IL-2. This establishes the difference between mouse and human IL-2Rβ chains. Transfection of T cell clone 8.2 with human IL-2Rα genes restores their capacity to proliferate in response to IL-2. In addition, all transfectants grown in IL-2 express the endogeneous mouse IL-2Rα chain. When grown in IL-4, the endogeneous mouse IL-2Rα gene remains silent in all these transfectants. These results show that, contrary to the human, the mouse does not express an intermediate-affinity IL-2R. Expression of the IL-2Rα gene is therefore required for the formation of the functional IL-2R in mice.  相似文献   
98.
Hepatitis C virus (HCV) infection is characterized by persistence of liver inflammation that often leads to end-stage liver disease, although the mechanisms are not fully understood. A hyper-variable region (HVR) has been reported in the E2/NS1 region of the HCV genome, in which striking diversity is found among different HCV isolates. To investigate the association of the HVR alterations with the clinical courses of HCV infection, a longitudinal analysis of the HVR in patients with acute HCV infection was carried out. Plasma samples were obtained at several times in three patients with acute hepatitis C. Plasma RNA was extracted and reverse transcribed, and DNA fragments that included the HVR were amplified by PCR. The sequences of the HVR were directly determined from the PCR products by the dideoxy chain termination method, from which amino acid sequences were deduced. In all cases, plasma HCV-RNA disappeared with the improvement of the initial alanine aminotransferase (ALT) elevation, but HCV-RNA reappeared about 1 year later with or without deterioration of the hepatitis. In a case of sporadic acute hepatitis, the HCV in the recurrent phase had seven amino acid substitutions in the HVR compared with that in the acute phase, although no amino acid changes were noted during the initial acute phase. In a case of posttransfusion hepatitis, a marked difference was observed between the acute and the recurrent phases, with an amino acid homology of 30% (8/27). The mutation rate of the HVR had a tendency to accelerate as the HCV infection progressed to the chronic stage. In conclusion, the HVR changes serially during the course of acute HCV infection, and these HVR changes may play a part in the chronicity of HCV infection. © 1994 Wiiey-Liss, Inc.  相似文献   
99.
Clinical usefulness of urinary diacetylpolyamines as novel tumor markers   总被引:1,自引:0,他引:1  
N1,N12-Diacetylspermine(DiAcSpm) and N1,N8-diacetylspermidine(DiAcSpd) are excreted in the urine of healthy persons as minor components of urinary polyamine, with small individual variations in amount. They are promising tumor markers, since their excretion is frequently elevated in patients with various types of cancers. DiAcSpm is sensitive in cancer detection, while DiAcSpd is highly specific for cancer. Diacetylpolyamines were initially characterized and determined by HPLC fractionation, followed by enzymatic detection. More recently, antibodies highly specific for DiAcSpm and DiAcSpd were developed, and an ELISA system applicable to the determination of urinary DiAcSpm was established. Measurement of urinary DiAcSpm using this ELISA system revealed that DiAcSpm is a more sensitive tumor marker than CEA, CA19-9 and CA15-3 for colon and breast cancers. More importantly, DiAcSpm efficiently detects patients at early stages. On the other hand, CEA, CA19-9 and CA15-3 are quite insensitive for early stage cancers. The urinary DiAcSpm level tends to remain low even in tumor-bearing individuals when their cancerous lesions remain static, while it rises rapidly concomitant with recurrence. DiAcSpm may serve as a prognostic indicator and marker for recurrence of prostate and colon cancers. Diacetylpolyamines may turn out to be general tumor markers, since active proliferation of any cancer tissues would likely be accompanied by activation of polyamine metabolism.  相似文献   
100.
BACKGROUND: Manual puncture of the trophectoderm of human blastocysts with a needle before vitrification increases their survival rate, but the embryos take a long time to re-expand. This study examined whether causing human blastocysts to collapse by manual pipetting before vitrification would allow more rapid re-expansion and improve pregnancy rates. METHODS: After embryo transfer in IVF cycles, surplus embryos that developed to the expanded blastocyst stage were placed in cryoprotectant and then artificially shrunk by mechanical pipetting with a fine hand-drawn glass pipette slightly smaller in diameter than the blastocyst. The shrunken embryos were placed in a small volume of vitrification solution and plunged into liquid nitrogen on a cryotop. The blastocysts were thawed by warming and then dilution in 1 mol/l sucrose. RESULTS: Of 49 expanded vitrified blastocysts, 48 (98%) re-expanded within 3 h after warming. Following transfer (48 blastocysts in 28 cycles), 14 women (50%) became clinically pregnant, and the implantation rate was 33% (16/48). Eight healthy babies have been born in six deliveries, and the other eight pregnancies are ongoing. To date, there have been no spontaneous abortions. CONCLUSIONS: The results suggest that artificial shrinkage with pipetting is a simple and effective technique to assist successful cryopreservation of expanded blastocysts by vitrification.  相似文献   
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