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101.
Hagihara K Yamane T Aoyama Y Nakamae H Hino M 《Annals of clinical and laboratory science》2005,35(1):31-36
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
102.
Arpp,a new homolog of carp,is preferentially expressed in type 1 skeletal muscle fibers and is markedly induced by denervation 总被引:3,自引:0,他引:3
Tsukamoto Y Senda T Nakano T Nakada C Hida T Ishiguro N Kondo G Baba T Sato K Osaki M Mori S Ito H Moriyama M 《Laboratory investigation; a journal of technical methods and pathology》2002,82(5):645-655
In this study, we isolated and characterized a murine counterpart of the human Arpp (hArpp) gene. Sequence analysis revealed that the murine Arpp (mArpp) gene is almost identical to the Ankrd2 gene, which has recently been isolated as a mouse gene induced in stretched skeletal muscle. The mArpp gene encodes a protein of 332 amino acids that contains four well-conserved ankyrin-repeat domains in the central portion of the protein. The amino acid sequence of mArpp protein (mArpp) is highly homologous to that of mouse cardiac-restricted ankyrin-repeat protein (Carp), which is proposed to be a putative genetic marker for cardiac hypertrophy. Immunohistochemical analysis revealed that mArpp is preferentially expressed in type 1 skeletal muscle fibers, and that mArpp is localized in both the nucleus and the sarcomeric I-band of muscle fibers, suggesting that Arpp may function as a nuclear and sarcomeric protein. Furthermore, mArpp was also expressed in neurons of the cerebellum and cerebrum, the islets of Langerhans in the pancreas, and the esophageal epithelium, suggesting that mArpp may play a functional physiologic role in brain, pancreas, and esophagus as well as in type 1 muscle fibers. Interestingly, although mArpp was localized in both nucleus and cytoplasm in neurons, its localization was restricted to nucleus in pancreas and esophagus, suggesting that intracellular localization of mArpp is regulated in a tissue-specific manner. Furthermore, we found that mArpp- and Carp-expression in skeletal muscle were markedly up-regulated after denervation. Although the elevated expression level of Carp was kept only for two weeks after denervation, that of Arpp was kept at least for 4 weeks, suggesting that mArpp and Carp may play distinct functional roles in denervated skeletal muscle. 相似文献
103.
Hori S Nakano Y Furukawa TA Ogasawara M Katano K Aoki K Kitamura T 《American journal of reproductive immunology (New York, N.Y. : 1989)》2000,44(5):299-302
PROBLEM: The preconceptional natural-killer cell (NK) activity predicts subsequent miscarriage among women with unexplained recurrent spontaneous abortion (RSA). Psycho-neuro-immuno-endocrine network has recently been proposed as a mechanism for abortions. We therefore examined which psychosocial factors influenced the NK activity among women with RSA. METHOD OF STUDY: We measured the preconceptional NK activity of 61 women with a history two consecutive unexplained first-trimester miscarriages and no live births. We also administered semi-structured interviews and a battery of self-report questionnaires to assess their social support, personality, self-esteem and psychiatric symptoms. RESULTS: The preconceptional NK activity was negatively correlated with the women's neuroticism personality trait (r= -0.32, P = 0.01) and current depressive symptoms (r = -0.26, P= 0.05), and positively correlated with their self-esteem (r = 0.34, P = 0.01). CONCLUSIONS: In addition to several substances such as transforming-growth-factor beta and granulocyte-macrophase colony-stimulating factor, we found that low neuroticism, low depression scale score and high self-esteem contributed to high NK activity among women with RSA. 相似文献
104.
Rabbit factor P, which is involved in stabilizing the labile C3 convertase of the alternative complement pathway, was isolated from rabbit serum by a simple two-step procedure: polyethylene glycol precipitation and QAE-Sephadex A-50 column chromatography. The chemical properties, and functional activities of the rabbit P were very similar to those of human P, except that there were slight differences in the SDS-PAGE patterns of limited tryptic digests and in the amino terminal sequences. The molecular weights were estimated to be 58 000 for rabbit P and 59 000 for human P on SDS-PAGE under reducing conditions. The amino terminal 36 residues of rabbit P showed 78% homology to the equivalent region of human P. 相似文献
105.
Regardless of the side of hemiovariectomy, unilateral lesion placed in the right-side medial anterior hypothalamus suppressed ovarian compensatory hypertrophy, but the lesion made in the left side failed to suppress it. This suggests the presence of a hypothalamic laterality in regulating gonadotropin secretion. 相似文献
106.
Orthopoxvirus DNA: strain differentiation by electrophoresis of restriction endonuclease fragmented virion DNA. 总被引:6,自引:0,他引:6
Procedures were developed for purifying intact intracytoplasmic poxvirus particles from infected cells and for isolating DNA from virions by equilibrium centrifugation in sodium diatrizoate density gradients. The buoyant density of twelve closely related orthopoxviruses purified in these gradients was determined to be 1.25 g/ml, and that of the isolated virion DNAs was 1.1 g/ml. Virion DNA from each of the 12 selected prototype and wild-type viruses was cleaved with three separate site-specific restriction endonucleases, Hin d III, Sal I, and Bam HI, and the fragments (molecular weights 0.5 × 106 to 20 × 106) were separated by agarose gel electrophoresis. Characteristic DNA fragment migration patterns observed in the gels permitted classification of the viruses. By comparing profiles of Hin d III cleaved DNAs we were able to group the viruses into 4 species: cowpox, vaccinia, monkeypox (2 isolates), and variola (8 isolates). Viruses from variola major infection could be differentiated from viruses from variola minor infection. Isolates within species (strains) were also differentiated, mainly by comparing the gel electrophoresis profiles of Sal I digested DNA from the viruses. 相似文献
107.
Makoto Nagasaki Takayuki Harada Ikuko Torii Akinobu Nakano Hiroshi Furuya Junichi Tanaka Kanji Hirai Shigeru Morikawa 《Pathology international》1994,44(12):850-856
A case of acquired immunodeficiency syndrome (AIDS) with preceding aplastic anemia is reported. The patient was a 36 year old female who had been diagnosed as having aplastic anemia 10 years before and thereafter had received multiple transfusions. Human immunodeficiency virus (HIV)-seropositivity was revealed 10 months prior to her death, but no particular clinical signs indicating HIV infection, pre-AIDS or onset of AIDS were recognized before serological diagnosis, although the slow progression of leukopenia was noted along with thrombocytopenia. Her general condition deteriorated during the last 10 months accompanied by an acute decrease In the CD4/CD8 ratio. Autopsy revealed full-blown AIDS: systemic aspergillosis, progressive multifocal leukoencephalopathy, Epstein-Barr virus-related B cell lymphoma arising in the diaphragm and severe lymphocyte depletion in the lymph nodes and spleen. Markedly hypo-plastic bone marrow was considered to be primarily attributable to the aplastic anemia but the affection of AIDS was not excluded. The possible transmission route of HIV and the effect of the preceding aplastic anemia on the infection and clinical course of AIDS are discussed. 相似文献
108.
A case of polypoid carcinosarcoma of the esophagus is presented. Histologically the bulk of the tumor consisted of a sarcomatous tissue having large foci of osseous and cartilagenous differentiation and infiltrating deeply the wall, whereas a superficially, invasive squamous cell carcinoma associated with insitu carcinoma was located at the base and luminal surface of the polypoid tumor. Intermingling of the carcinomatous and sarcomatous elements was found only in areas where they appeared to be collided. Ultrastructurally the sarcomatous portion contained cells with fibroblastic features but with no typical epithelial characteristics. Immunoperoxidase staining of the paraffinembedded histologic sections for keratin proteins revealed, however, some positive spindle cells indicative of epithelial nature in the sarcomatous area, but the great majority of the sarcoma cells were devoid of keratin. These combined findings strongly suggest that the sarcomatous component in our case of true carcinosarcoma is derived from mesenchymal transformation (metaplasia) of the squamous carcinoma cells. The findings were discussed in light of the previous pertinent literature. ACTA PATHOL, JPN. 34: 669–678, 1984. 相似文献
109.
Histamine synthesis by non-mast cells through mitogen-dependent induction of histidine decarboxylase. 总被引:2,自引:0,他引:2 下载免费PDF全文
Culture of spleen cells of C57BL/6 mice led to a spontaneous increase in activity of histidine decarboxylase (HDC) in the cell and the medium. Concomitantly histamine increased in the cells and, especially, in the medium. Addition of concanavalin A (Con A) or lipopolysaccharide (LPS) to the culture enhanced these processes. There was also a significant Con A-dependent increase in HDC activity and histamine biosynthesis in the culture of spleen cells of genetically mast-cell deficient W/Wv mice. Peritoneal macrophages of C57BL/6J mice had constitutively 11-19-fold as much HDC as T and B lymphocytes when compared on the basis of same number of cells. Con A had no effect on HDC activity when the macrophages were cultured alone. However, co-culture with T lymphocytes, separated from macrophages by a millipore filter membrane (pore size, 0.45 micron), rendered the macrophages responsive to Con A, leading to a notable increase in HDC activity in the cell. Addition of LPS caused a small but significant increase in HDC activity in macrophages, even when the cells were cultured alone. Co-culture with T or B cells enhanced the LPS-dependent increase in HDC activity in macrophages. In contrast, the HDC activity in T and B lymphocytes did not change essentially in the presence of any of these mitogens, even when they were co-cultured with macrophages. These results suggest that histamine is synthesized by non-mast cells through HDC. 相似文献
110.
Zhang T Maekawa Y Sakai T Nakano Y Ishii K Hisaeda H Dainichi T Asao T Katunuma N Himeno K 《International immunology》2001,13(8):975-982
Prior to the activation of CD4 (+) T cells, exogenous proteins must be digested by endo/lysosomal enzymes in antigen-presenting cells (APC) to produce antigenic peptides that are able to be presented on class II molecules of the MHC. Studies described here inspect the functional significance of cathepsin L inhibition for antigen processing and T (h) 1/T (h) 2 differentiation in experimental leishmaniasis. We first demonstrated using in vitro systems that cathepsin L is one of the candidate endo/lysosomal enzymes in processing of soluble Leishmania antigen (SLA) and that its specific inhibitor, CLIK148, modulated the processing of SLA. BALB/c mice are known to be susceptible to infection with Leishmania major. Interestingly, treatment of BALB/c mice with CLIK148 exacerbated the infection by enhancing the development of SLA-specific T (h) 2-type response such as production of IL-4 and generation of T (h) 2-dependent specific IgE/IgG1 antibodies. Moreover, addition of CLIK148 in incubation of a SLA-specific CD4 (+) T cell line with APC up-regulated the production of IL-4. However, CLIK148 did not exert any direct influence on the function of T cells themselves. Taken together, these findings suggest that treatment of host mice with CLIK148 affects the processing of SLA in APC, resulting in the potentiation of T (h) 2-type immune responses and thus leading to exacerbation of the infection. Furthermore, endo/lysosomal cathepsin L was found to be functionally distinct from previously described cathepsins B and D. 相似文献