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131.
Sakurai Y Shoji M Matsubara T Imazu H Hasegawa S Ochiai M Funabiki T Mizoguchi Y Kuroda M Kasahara M 《Pathology international》2000,50(8):655-659
Angiomyomatous hamartoma is a rare disease with a predisposition for the inguinal lymph nodes. A 51-year-old male patient visited a local hospital because of a right inguinal mass, measuring 3 x 4 cm in size, which was resected. The resected specimen showed irregularly distributed thick-walled vessels in the hilum, extending into the medulla and focally into the cortex of the node, eventually becoming more dispersed and associated with smooth muscle cells splaying into sclerotic stroma. These findings are compatible with an angiomyomatous hamartoma. Another tumor-like mass appeared shortly after the resection at the same location, but was not an angiomyomatous hamartoma, rather it was composed of edematous stromal tissue with proliferating smooth muscle cells. The stromal component included thick-walled blood vessels and lymphatics. Although it could not be determined whether these associated changes in the surrounding stroma are a cause or an effect of angiomyomatous hamartoma, they indicate the clinical difficulty in determining an appropriate area of resection and may provide clues to the pathogenesis of angiomyomatous hamartoma. 相似文献
132.
Minced and triturated fragments from the spinal cord of normal rat fetuses (15-18 days gestation) labeled with the fluorescent dye fast blue (FB) were successfully transplanted into juvenile myelin-deficient rat spinal cord under direct observation. Clusters of myelinated fibers were found subsequently in the recipient spinal cord, and, by fluorescence microscopy, clusters of FB-labeled cells were found at corresponding sites. The results indicate that the surgical approach used is suitable for transplantation of tissue fragments into a defined region of juvenile rat spinal cord, that FB can be used to locate the transplanted cells subsequently, and that FB does not interfere with maturation of the donor glia or with myelin formation. 相似文献
133.
Watanabe T Hasegawa G Yamamoto T Hatakeyama K Suematsu M Naito M 《Archives of histology and cytology》2003,66(2):155-162
Heme oxygenase (HO), the heme-degrading enzyme, plays an important role in heme catabolism. Among three isozymes, HO-1 is an inducible form expressed mainly in macrophages. In rat ontogeny, HO-1 immunoreactivity was detected in mononuclear cells in the yolk sac at 10 days of gestation. HO-1-expressing cells were then detected in the fetal liver and their numbers increased during the gestational period. The numbers of HO-1-positive cells and HO-1 mRNA levels in the liver peaked at 18 days of gestation. Most of the macrophages expressed both HO-1 and a macrophage scavenger receptor. Macrophages in the fetal liver showed marked hemophagocytosis. Macrophages in the lung, spleen, bone marrow, and other tissues also expressed HO-1. HO-1 immunoreactivity was also observed in syncytial cells of the chorionic villi, the endodermal layer of the yolk sac, and renal tubules of the fetus. Intestinal mucosal epithelial cells expressed HO-1 after birth. These findings imply that HO-1 is crucial for macrophages in heme catabolism from an early stage of ontogeny. HO-1 expression in non-macrophagic cells may be required for other purposes such as protection from oxidative stress and various stimuli. 相似文献
134.
Murata K Inami M Hasegawa A Kubo S Kimura M Yamashita M Hosokawa H Nagao T Suzuki K Hashimoto K Shinkai H Koseki H Taniguchi M Ziegler SF Nakayama T 《International immunology》2003,15(8):987-992
CD69, known as an early activation marker antigen on T and B cells, is also expressed on platelets and activated neutrophils, suggesting certain roles in inflammatory diseases. In order to address the role of CD69 in the pathogenesis of arthritis, we established CD69-null mice. CD69-null mice displayed a markedly attenuated arthritic inflammatory response when injected with anti-type II collagen antibodies. Cell transfer experiments with neutrophils, but not T cells or spleen cells, from wild-type mice into CD69-null mice restored the induction of arthritis. These results indicate a critical role for CD69 in neutrophil function in arthritis induction during the effector phase. Thus, CD69 would be a possible therapeutic target for arthritis in human patients. 相似文献
135.
Shibahara H Tsunoda T Taneichi A Hirano Y Ohno A Takamizawa S Yamaguchi C Tsunoda H Sato I 《American journal of reproductive immunology (New York, N.Y. : 1989)》2002,47(3):146-150
PROBLEM: The presence of antisperm antibodies (ASA) in males can reduce fecundity, however, relationship between the two is disputed. This study was performed to investigate if there is diversity of ASA bound to sperm surface using immunobead test (IBT) combined with complement dependent sperm immobilization test (SIT). METHODS: The ASA bound to sperm surface were detected using the direct IBT (D-IBT) in 275 semen samples. In some cases with ASA detected by D-IBT, sperm immobilizing antibodies bound to sperm surface were also evaluated using direct SIT (D-SIT). RESULTS: The incidence of the immunoglobulin G (IgG), IgA, and IgM classes of ASA detected by D-IBT were 2.5, 1.8, and 0.4%, respectively. Totally, nine (3.3%) infertile men had ASA on the sperm surface. D-SIT was tested positive in four (66.7%) of six cases with ASA assessed by D-IBT. CONCLUSIONS: Some of the sperm-bound antibodies are associated with complement dependent sperm immobilizing antibodies, indicating that there exists a heterogeneity of sperm-bound antibodies. This result might be one of the reasons for the controversy about the relationship between ASA and immunological infertility in men. 相似文献
136.
Hirata T Iida A Shiraki-Iida T Kitazato K Kato A Nagai Y Hasegawa M 《Journal of virological methods》2002,104(2):125-133
An improved system is described to recover non-transmissible Sendai virus that lack the envelope fusion (F) gene from cloned cDNA. The system (1) used plasmids that expressed the F and the HN viral envelope proteins, as well as the plasmids that expressed the viral NP, P, and L proteins as helper plasmids for recovery, and (2) overlaid packaging cells that expressed the F protein. With this improved system, we have succeeded in recovery of F-defective Sendai virus expressing two foreign proteins, and expression vectors that do not contain the EGFP reporter gene. This system may provide the basis for constructing recombinant F-defective Sendai virus for preventing and treating human diseases in the form of vaccines and vectors for gene therapy. 相似文献
137.
Prognostic significance of histologic grade and nuclear expression of beta-catenin in synovial sarcoma 总被引:2,自引:0,他引:2
Synovial sarcoma, which has a wide spectrum of biologic behavior, warrants accurate grading to assess the patient's prognosis. We studied the clinicopathologic and immunohistochemical features of 44 cases of synovial sarcoma in patients treated primarily or secondarily at the National Cancer Center, Tokyo, to identify independent prognostic factors. There were local recurrences in 16 patients (36%), and 25 (57%) developed metastases, primarily to the lungs. The estimated cumulative 5-year and 10-year survival rates were 68% and 41%, respectively. Variables associated with an adverse outcome included tumor size > 6.7 cm; initial treatment outside the National Cancer Center; poorly differentiated subtype; high nuclear atypia; mitosis count > 27/10 high-power fields; tumor necrosis; absence of stromal calcification; nuclear expression of beta-catenin, which was found in 25 cases (57%); Ki-67 (MIB-1) index > 27%; and histologic grade 3. Nuclear accumulation of beta-catenin as a cell-signaling event may play an important role in the progression of synovial sarcoma and therefore might be predictive of short survival. However, multivariate analysis clearly showed that only histologic grade, as defined by using categorized variables for the MIB-1 index and tumor necrosis, was an independent prognostic factor. Most variables were correlated with lung metastasis and histologic grade. High-grade synovial sarcoma assessed by a histologic grading system based on the proliferative activity of the neoplastic cells can be viewed as high risk with the patients most likely to die of disease within 10 years after surgery and in need of improved chemotherapy. HUM PATHOL 32:257-263. 相似文献
138.
139.
Polymorphism in RANTES chemokine promoter affects extent of sarcoidosis in a Japanese population 总被引:3,自引:0,他引:3
Takada T Suzuki E Ishida T Moriyama H Ooi H Hasegawa T Tsukuda H Gejyo F 《Tissue antigens》2001,58(5):293-298
RANTES, a member of C-C chemokine, is known to be produced at sites of granulomatous reactions in the lung of sarcoidosis. RANTES is a potent eosinophil and lymphocyte attractant with particular preference for CD45RO+ T cells and eosinophils. Polymorphism of the RANTES promoter has recently been shown to be related to allergic and infectious diseases; atopic dermatitis, asthma, and polymyalgia rheumatica. Considering that this might affect sarcoidosis, we studied polymorphism of the RANTES gene in 114 patients with sarcoidosis and 136 healthy control subjects. Their genotypes were determined using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). Although no difference in the genotype distribution between healthy control subjects and sarcoidosis patients was identified, the difference in the frequencies of the patients with three or more organ involvement was significant (P<0.01) with the frequency of those in AA genotype being elevated (P<0.05). BAL findings in 48 out of 114 patients who underwent bronchoscopy were reviewed. The CD4/8 ratio of lymphocytes in bronchoalveolar lavage fluid in the patients with AA genotype was significantly increased (P<0.05). From the results, we suggest that in RANTES gene polymorphism the homozygous A allele might be a genetic risk factor for extent disease of sarcoidosis. 相似文献
140.
Yoshinobu Uno Chizuko Nishida Yuki Oshima Satoshi Yokoyama Ikuo Miura Yoichi Matsuda Masahisa Nakamura 《Chromosome research》2008,16(4):637-647
There are regional variations of sex chromosome morphologies in the Japanese wrinkled frog, Rana rugosa (2n = 26): heterogametic ZZ/ZW-type and XX/XY-type sex chromosomes, and two different types of homomorphic sex chromosomes. To search for homology between the ZW and XY sex chromosomes and the chromosome rearrangements that have occurred during sex chromosomal differentiation in R. rugosa, we performed chromosome mapping of sexual differentiation genes for R. rugosa by FISH. Three genes, AR, SF-1/Ad4BP and Sox3, were localized to both the ZW and XY chromosomes, and their locations were all different between the Z and W and between the X and Y. AR and SF-1/Ad4BP were located on the short arms of the W and X and the long arms of Z and Y, and Sox3 was mapped to the different locations on the long arms between the Z and W and between the X and Y, probably as a result of multiple rearrangements that occurred during the process of sex chromosome differentiation. However, the chromosomal locations of three genes were almost consistent between the Z and Y and between the W and X, indicating that the Z and Y chromosomes and the W and X chromosomes were respectively derived from the same origins. Dmrt1, which is located on avian sex chromosomes, was localized to autosomes in R. rugosa with both the ZW and XY sex chromosomes, suggesting that Dmrt1 might not be related to sex determination in this species. 相似文献