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31.
32.
Loss of mammalian Sprouty2 leads to enteric neuronal hyperplasia and esophageal achalasia 总被引:3,自引:0,他引:3
Taketomi T Yoshiga D Taniguchi K Kobayashi T Nonami A Kato R Sasaki M Sasaki A Ishibashi H Moriyama M Nakamura K Nishimura J Yoshimura A 《Nature neuroscience》2005,8(7):855-857
We report here that loss of the Sprouty2 gene (also known as Spry2) in mice resulted in enteric nerve hyperplasia, which led to esophageal achalasia and intestinal pseudo-obstruction. Glial cell line-derived neurotrophic factor (GDNF) induced hyperactivation of ERK and Akt in enteric nerve cells. Anti-GDNF antibody administration corrected nerve hyperplasia in Sprouty2-deficient mice. We show Sprouty2 to be a negative regulator of GDNF for the neonatal development or survival of enteric nerve cells. 相似文献
33.
34.
Bi X Gatanaga H Tanaka M Honda M Ida S Kimura S Oka S 《Journal of acquired immune deficiency syndromes (1999)》2005,38(1):1-4
The Dynabeads method showed the potential for enumerating CD4 T lymphocytes (CD4 count) in HIV-1-infected individuals. The large volume of Dynabeads required for 1 sample and complex procedure made the method expensive and not easy for use, however. To decrease the cost and simplify the procedure, we reduced the volume of the Dynabeads, added wash times, and skipped over the staining step so as to count the CD4 cells directly under an optical microscope. The CD4 count of 246 blood samples using our modified Dynabeads method (DynabeadsCD4) showed a significant correlation with that obtained by flow cytometry (FlowcytoCD4) (r = 0.91 [P < 0.0001]; slope = 1.03, intercept = -16). The sensitivity and specificity for a CD4 count less than 200 cells/microL were 79% and 94%, and for a CD4 count less than 350 cells/microL, the sensitivity and specificity were 95% and 88%, respectively. The positive and negative predictive values for a CD4 count less than 350 cells/microL were 97% and 83%, respectively. The systematic error was 8 cells/microL (95% confidence interval [CI]: 0.4-16). The cost of Dynabeads for 1 sample was less than $1.00; thus, the estimated cost per DynabeadsCD4 test is less than $3.00, including the cost of other disposable materials. Our modified method is simple, economic, and accurate enough to monitor antiretroviral therapy in resource-limited situations. 相似文献
35.
Biosynthesis and secretion of the third component of complement by human endothelial cells in vitro. 总被引:8,自引:0,他引:8
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The third component of complement (C3) is synthesized and released by cultured human capillary endothelial cells. After the incubation of cells in a methionine-free medium containing 35S-methionine for 48 hr, culture supernatants were immunoprecipitated with anti-human C3 serum. SDS solubilization and 2-ME reduction of the immunoprecipitates, followed by separation with SDS-polyacrylamide gel electrophoresis and autoradiography, revealed two major bands comparable to those of the alpha and beta chains of human C3. The content of C3 in the culture medium harvested at different time-intervals was determined by ELISA. The C3 secretion rate was about 250 ng/10(6) cells/5 days in the primary culture medium and 75 ng/10(6) cells/5 days after seven passages. The capillary endothelial cells described here have factor VIIIRAg specific for endothelial cells, and exhibit ring formation resembling capillary lumina, but they lack Weibel-Palade bodies. 相似文献
36.
Satoshi Mochida Itsuro Ogata Yasuhiko Ohta Teruaki Oka Kenji Fujiwara 《Pathology international》1991,41(3):217-220
In order to investigate superoxide production by pulmonary macrophages in the rat, a route was created by ligating both the inferior and superior venae cavae and resecting the aorta after cannulation through the inferior vena cava into the right atrium of the heart. Lung perfusion was performed via this route with nitro blue tetrazolium. Although there was no formazan deposition throughout the lung, it became detectable in both alveolar and interstitial macrophages when phorbol myristate acetate was added to the perfusate. This deposition was markedly enhanced by previous injection of Corynebacterium parvum. The deposition disappeared after further addition of Cu(Lys)2 , a scavenger of superoxide anions. This procedure may be useful for estimating in situ the ability of pulmonary macrophages to produce superoxide in the rat. 相似文献
37.
A Masunaga T Oka H Nakamura K Kinoshita T Yamashita I Sugawara S Itoyama 《Acta pathologica japonica》1992,42(12):916-922
A case of intrauterine tumor in a 62-year-old Japanese woman is presented. It was thought initially that this was a case of uterine tumor resembling an ovarian sex cord tumor. To examine the cytological features of the tumor cells, electron microscopical and immunohistochemical studies were done, and a hormone assay of the tumor tissue was performed. The tumor cells were rich in rough endoplasmic reticulum (rER), mitochondria and microfilaments. Some tumor cells tended to form glandular patterns, but these epithelial elements were frequently scattered among fibrous stromal elements. Though many tumor cells with an epithelial appearance possessed a large quantity of cytokeratin and vimentin, they did not secrete estradiol, progesterone, testosterone or human chorionic gonadotropin. This case was finally diagnosed as an intramural uterine stromal tumor with epithelial differentiation after taking all the available data into consideration. This would be classified as an endometrial stromal tumor with epithelial elements, recently proposed and named by Clement and Scully. 相似文献
38.
H. Oka T. Kameya H. Sasano M. Aiba K. Kovacs E. Horvath Y. Yokota N. Kawano K. Yada 《Virchows Archiv : an international journal of pathology》1996,427(6):613-617
A pituitary tumour composed of well-differentiated corticotrophs and adrenocortical cells is reported. Sections of the tumour revealed a mixture of small round cells with amphophilic or basophilic periodic acid-Schiff (PAS)-positive cytoplasm and large spherical and oval cells with abundant, granular, partly vacuolated PAS-negative cytoplasm. The small cells contained type 1 cytokeratin-positive microfilaments, numerous 250–500 nm endocrine-type secretory granules immunoreactive for adenocorticotropic hormone (ACTH) and -lipotropin. The large cells possessed ample cytoplasm filled with abundant vesicular smooth endoplasmic reticulum, numerous mitochondria possessing tubulovesicular cristae and frequent dense bodies. They lacked the features of pituitary endocrine cells or folliculostellate cells and were found to contain a panel of steroidogenic dehydrogenases and hydroxylases. The tumour was classified as a choristoma, in which two distinct cells types, corticotrophs and adrenocortical cells, were mixed. We suggest that, under continued ACTH stimulation, uncommitted stem cells may differentiate into adrenocortical cells. Alternatively, the presence of adrenocortical cells may be the result of heterotopia. 相似文献
39.
Malignant histiocytosis. A report of three cases. 总被引:1,自引:0,他引:1
Three cases of malignant histiocytosis were immunohistochemically studied. The cases included the following three patients: a 38-year-old man, a 44-year-old man, and a girl aged 5 years 9 months. All three patients died within 3 months of hospitalization. They had a high fever (temperature over 38.5 degrees C), lymph node swelling, hepatosplenomegaly, and pancytopenia. Blastoid and hemophagocytic cells proliferated in the bone marrow and lymph nodes, especially in the sinuses of the latter. We diagnosed malignant histiocytosis in the three cases based on clinical features, extremely poor prognoses, and the morphologic features and growth pattern of blastoid and hemophagocytic cells. Blastoid and hemophagocytic cells expressed phenotype Mac-387+/KP1+/lysozyme+/polyclonal CD3+. The Mac-387 and KP1 antigens and lysozyme are markers for monocytes/macrophages, and polyclonal CD3 is a marker for T lymphocytes. Therefore, we suggest that a certain number of cases of malignant histiocytosis have a biphenotypic nature, namely, the T cell and macrophage, although many cases of malignant histiocytosis have been reported as expressing only T-lymphocyte antigens. 相似文献
40.
Pituitary Adenylate-Cyclase-Activating Polypeptide (PACAP) Binding Sites and PACAP/Vasoactive Intestinal Polypeptide Receptor Expression in Human Pituitary Adenomas
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