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121.
An immunohistochemical study of bone morphogenetic protein in pleomorphic adenoma of the salivary gland 总被引:4,自引:0,他引:4
Yang Lianjia Jin Yan Nakamine Hitoshi Sumitomo Shinichiro Kamegai Akihide Mori Masahiko 《Virchows Archiv : an international journal of pathology》1993,422(6):439-443
Bone morphogenetic protein (BMP) is a potent induction factor for new bone formation including heterotopic chondro-ossification in soft tissues. The immunohistochemical reaction for BMP was studied in 23 cases of pleomorphic adenoma of salivary gland by using a monoclonal antibody produced by hybridoma technique. Positive BMP immunoreactivity was seen in 87% of tumours. Immunohistochemical expression of BMP was observed in modified myoepithelial cells (88% cases), luminal tumour cells of tubulo-ductal structures (78% cases) and chondroid cells in hyaline tissue (22% cases). The authors concluded that the simultaneous presence of glycosaminoglycans as matrix substance and S-100 protein for calcium signalling are associated with BMP-mediated cellular activity of modified myoepithelial cells in the formation of chondroid structures in pleomorphic adenomas of the salivary glands. 相似文献
122.
Takao Hijikata Hitoshi Wakisaka Shumpei Niida 《Anatomical record (Hoboken, N.J. : 2007)》1993,236(4):602-610
Using digital image analysis and several anatomical methods, morphometric analysis of nonspanning fibers which had tapering profiles at their intrafascicular termination sites and represented overlapping arrangements within the fiber fascicles was performed in the rat rectus abdominis. Special emphasis was focused on dimensional relationships occurring between overlapping portions and tapering segments and sarcomere lengths in non- and overlapping portions. Nonspanning fibers were found to overlap each other for more than 40% of their length. In length, their overlapping portions generally corresponded to their tapering segments, which were also greater than 40% of the fiber length. In addition, despite the presence of overlapping linkages, nonspanning fibers maintained a fairly uniform length irrespective of their overlapping and non-overlapping portions. Overlapping linkages in fibers without tapering profiles have a larger cross-sectional area in the overlapping portion than in the non-overlapping one, resulting in a phenomenon which will cause different sarcomere lengths between the two portions during fiber stretching. The present results suggest that tapering profiles in the overlapping portion ensure uniform sarcomere lengths within nonspanning fibers, thereby providing mechanical stability in each fiber. © 1993 Wiley-Liss, Inc. 相似文献
123.
Immune Abnormalities Induced by Human Endogenous Retroviral Peptides: With Reference to the Pathogenesis of Systemic Lupus Erythematosus 总被引:1,自引:0,他引:1
Naito T Ogasawara H Kaneko H Hishikawa T Sekigawa I Hashimoto H Maruyama N 《Journal of clinical immunology》2003,23(5):371-376
P15E is a specific sequence among the envelope gene (env)-encoded transmembrane proteins of exogenous and endogenous retroviruses. A synthetic peptide (CKS-17) that shows homology to this p15E region in several species of retrovirus is known to induce immune abnormalities. In this study, we examined the effect of a synthetic peptide derived from a region of human endogenous retrovirus (HERV) clone 4-1 ( 4-1) similar to sequences of CKS-17 on the induction of systemic lupus erythematosus (SLE)-related immune abnormalities. Our results indicated that this peptide could induce T-cell activation and anergy in normal peripheral blood mononuclear cells, and the peptide could also promote the production of interleukins IL-6 and IL-16. These phenomena are representative immune abnormalities observed in SLE patients. Thus, our findings support the possibility that HERV acts as a pathogen in human SLE. 相似文献
124.
The hydrophobic surface of oriented poly(propylene) film (OPP) was modified to a hydrophilic one by a novel photo-grafting procedure using acrylamide (AM) as monomer. A deoxygenated acetone solution containing AM and benzophenone (BP) or other sensitizers was brought into contact with OPP film and the reaction system was photoirradiated from the other side of the polymer film. Within a few minutes, surface photo-grafting resulted. The influences of solvent, sensitizer, and additives revealed that the graft polymerization was initiated by hydrogen abstraction from the polymer surface by the triplet excited state of the sensitizer. IR Spectroscopy as well as ESCA measurements confirmed that the graft polymerization occurred on the film surface. The wettability of the grafted OPP film is discussed and correlated with the relative amount of surface grafting. The contact angle of untreated OPP film to water (101°) decreased to ≈40° after surface photografting. The drastic change of surface properties makes the practical application of the present technique feasible. 相似文献
125.
126.
Hiroshi Kimoto Hitoshi Nagaoka Yoshihiro Adachi Toshiaki Mizuochi Takachika Azuma Takenori Yagi Tetsutaro Sata Shin Yonehara Yasuko Tsunetsugu-Yokota Masaru Taniguchi Toshitada Takemori 《European journal of immunology》1997,27(1):268-279
Well-developed germinal centers (GC) contain rapidly dividing surface immunoglobulin-negative (sIg-) B cells (centroblasts), and most of their progeny are sIg+ B cells (centrocytes) in a resting state. It has been predicted that somatic hypermutation occurs in centroblasts, whereas antigen-driven selection takes place in centrocytes. The present analysis indicates that murine GC B cells bearing sIg with specificity for an immunizing antigen are in a rapidly cycling state and increase exponentially in number to occupy spleen GC at high frequency during the 1st week after primary immunization; however, the number of these cells is significantly reduced in the 2nd week of immunization. During that period, these proliferating sIg+ GC B cells accumulate somatic hypermutations with nucleotide exchanges indicative of affinity maturation. These sIg+ GC B cells co-express B7-2, ICAM-1, and LFA-1, and have potent antigen-presenting activity which results in T cell activation in vitro. These observations indicate that the sIg+ GC B cells accumulate somatic hypermutations and undergo antigen-driven selection through proliferation, probably upon activation by T cells. This sIg+ GC B cell population may represent cell cycling centrocytes; however, the possibility that these may represent centroblasts undergoing re-expression of sIg could not be excluded. 相似文献
127.
Immunohistochemical,ultrastructural and biochemical studies of an amylase-producing breast carcinoma
Hideo Inaji Hiroki Koyama Masahiko Higashiyama Shinzaburo Noguchi Hitoshi Yamamoto Osamu Ishikawa Kaoru Omichi Takeshi Iwanaga Akira Wada 《Virchows Archiv : an international journal of pathology》1991,419(1):29-33
Summary We describe a breast cancer with ectopic production of amylase, found in the patient's serum, urine and in the tumour. Clinically, serum amylase levels reflected both the progression of the disease and regression induced by various therapies. Using agarose gel electrophoresis and a wheat protein inhibitor assay, the predominant serum amylase appeared to be identical to pancreatic-type isoenzyme. However, the action mode analysis using a new fluorogenic substrate revealed that the serum contained non-salivary, non-pancreatic amylase. The tumour had microscopic features of invasive ductal carcinoma with some argyrophilic differentiation. The component cells stained positively for amylase, and ultrastructurally numerous secretory granules were seen. 相似文献
128.
Expression of cyclin D1, retinoblastoma gene protein, and p16 MTS1 protein in atypical adenomatous hyperplasia and adenocarcinoma of the lung 总被引:2,自引:0,他引:2
Y. Kurasono Takaaki Ito Yoichi Kameda Nobuo Nakamura Hitoshi Kitamura 《Virchows Archiv : an international journal of pathology》1998,432(3):207-215
To clarify the events leading to the disruption of cell growth control that occurs during the development of pulmonary adenocarcinoma
(AC), we used immunohistochemistry to evaluate the expression of G1 cycle regulators, cyclin D1, Rb protein (pRb), and p16
MTS1 protein and the tumour proliferation marker, Ki 67, both in AC of the lung and in its precursor lesion, atypical adenomatous
hyperplasia (AAH). The frequency of lesions with cyclin D1 overexpression was relatively high in AAH (47–89%), but was decreased
in early AC (28%) and overt AC (35%). The loss of pRb expression was rare in both AAH (0–18%) and early AC (0%), and was infrequent
even in overt AC (13%). The loss of p16 expression was also relatively infrequent in both the premalignant and the malignant
lesions (11–25%). Our results suggest that overexpression of cyclin D1 is an early event and plays an important part in tumorigenesis
in the case of lung AC. However, cyclin D1 overexpression is not required for the development and maintenance of a malignant
phenotype. It is likely that some cyclin D1-independent pathways other than Rb and p16 abnormalities have an important role
in the malignant transformation from AAH to early AC.
Received: 8 July 1997 / 26 September 1997 相似文献
129.
Kawauchi S Okuda S Morioka H Iwasaki F Fukuma F Chochi Y Furuya T Oga A Sasaki K 《Human pathology》2005,36(10):1096-1100
Large cell neuroendocrine carcinoma (LCNEC) of the uterine cervix is a newly introduced category of the revised World Health Organization classification. We reported a case of cervical LCNEC with cytogenetic analysis by comparative genomic hybridization (CGH). The cervical tumor showed moderately increased mitotic activity (8-14 mitotic figures per 10 high-power fields) and focal necrosis, which made it problematic to differentiate from atypical carcinoid. CGH analysis failed to detect chromosome 11q loss that has been reported to be characteristic of pulmonary atypical carcinoids. Furthermore, chromosome 3q amplification, which has been detected frequently in pulmonary small cell carcinomas and LCNECs but not in pulmonary typical and atypical carcinoids, was the most remarkable chromosomal aberration. Although CGH reports are extremely rare in neuroendocrine tumors of the uterine cervix, specific chromosomal aberrations may be useful in their distinction. 相似文献
130.
Hironobu Tawaraya Showgo Ohkoshi Kenji Kuwana Masashi Watanabe Tomoteru Kamimura And Hitoshi Asakura 《Journal of medical virology》1995,45(4):367-372
Mass screening for hepatitis C virus antibody was carried out in 875 inhabitants (313 men and 562 women) of a town in Japan with a high rate of hepatitis B virus infection. The overall rate of positivity for anti-HCV was 8.8% (6.4% in men and 10,1% in women). The rate of positivity for hepatitis B virus surface antigen was 11.2%. Five subjects (0.6%) were positive for both markers. HCV-RNA was detected in 65 (88.4%) of 77 individuals who were positive for anti-HCV and in 1 (1.5%) of 60 individuals negative for anti-HCV. The genotype of the HCV genome was determined by PCR analysis using type-specific primers in 60 individuals. HCV type 1b was detected in 51 subjects (85%), type 2a in 3 subjects (5%), and type 2b in 6 subjects (10%). None of the individuals was infected with more than one genotype. The nucleotide sequences of the partial nonstructural 5 region of HCV type 1b genotype obtained from 6 individuals showed at least 92.0% homology in the nucleotide sequence, and 94.8% homology in the amino acid sequence. Homology among these clones was greater than their homology with previously described type 1 b sequences. The findings suggest that there was a specific local origin of HCV infection, although it was not possible to identify any single source of HCV infection. The results also indicate the presence of asymptomatic HCV carriers. © 1995 Wiley-Liss, Inc. 相似文献