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51.
Nakama S Kikuchi M Yashiro T Sakamoto A Kikkawa I Ookami H Saita K Hoshino Y 《Medical molecular morphology》2005,38(3):173-180
Ossification or calcification of the ligamentum flavum (LF) is relatively common in the middle and lower cervical, thoracic, and lumbar spine but extremely rare in the upper cervical region. This clinical fact suggests that there exist local factors promoting or preventing ossification or calcification of LF. However, little is known about the differences in the ultrastructure and cellular alterations of the LF between the different spinal levels, even in the cervical spine. With electron microscopy, we examined samples of LF collected surgically from the upper and lower cervical spine regions; we then studied the apoptotic appearance of ligament cells using a preferential labeling method. We found direct evidence of apoptosis of ligament cells in the LF. Apoptosis was more apparent in the upper region samples than in the lower region samples. The spaces around the normal fibroblasts were filled with thick collagen fibrils, but the collagen fibrils disappeared around the apoptotic bodies and thin fibrils were formed. The difference of the level of apoptosis may correlate to the ultrastructual difference of LF, and our data will benefit further investigations seeking to clarify the mechanism of various pathological conditions in the human LF. 相似文献
52.
The complete nucleotide sequence of rice tungro spherical virus (RTSV) strain Vt6, originally from Mindanao, the Philippines, with higher virulence to resistant rice cultivars, was determined and compared with the published sequence for the Philippine-type strain A (RTSV-A-Shen). It was reported that RTSV-A was not able to infect a rice resistant cultivar TKM 6 (10). RTSV-Vt6 and RTSV-A-Shen share 90% and 95% homology at nucleotide and amino-acid levels, respectively. The N-terminal leader sequence of RTSV-Vt6 contained a 39-amino acids-region (positions 65 to 103) which was totally different from that of RTSV-A-Shen; the difference resulted from frame shifting by nucleotide insertions and deletions. To confirm the amino-acid sequence differences of the leader polypeptide, the same region was cloned and sequenced using a newly obtained variant of RTSV-type 6, which had been collected in the field of IRRI, and seven field isolates from Mindanao, the Philippines. Since all the sequences of the target region are identical to that of the Vt6 leader polypeptide, the sequence difference in the leader region seems not to correlate with the virulence of Vt6. 相似文献
53.
54.
Morita Y Ujike H Tanaka Y Uchida N Nomura A Ohtani K Kishimoto M Morio A Imamura T Sakai A Inada T Harano M Komiyama T Yamada M Sekine Y Iwata N Iyo M Sora I Ozaki N Kuroda S 《Neuroscience letters》2005,376(3):182-187
Genetic contributions to the etiology of substance abuse and dependence are topics of major interest. Acute and chronic cannabis use can produce drug-induced psychosis resembling schizophrenia and worsen positive symptoms of schizophrenia. The endocannabinoid system is one of the most important neural signaling pathways implicated in substance abuse and dependence. The fatty acid amide hydrolase (FAAH) is a primary catabolic enzyme of endocannabinoids. To clarify a possible involvement of FAAH in the etiology of methamphetamine dependence/psychosis or schizophrenia, we examined the genetic association of a nonsynonymous polymorphism of the FAAH gene (Pro129Thr) by a case-control study. We found no significant association in allele and genotype frequencies of the polymorphism with either disorder. Because the Pro129Thr polymorphism reduces enzyme instability, it is unlikely that dysfunction of FAAH and enhanced endocannabinoid system induce susceptibility to either methamphetamine dependence/psychosis or schizophrenia. 相似文献
55.
56.
Immunofluorescence technique using HeLa cells expressing recombinant nucleoprotein for detection of immunoglobulin G antibodies to Crimean-Congo hemorrhagic fever virus
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Saijo M Qing T Niikura M Maeda A Ikegami T Sakai K Prehaud C Kurane I Morikawa S 《Journal of clinical microbiology》2002,40(2):372-375
A HeLa cell line continuously expressing recombinant nucleoprotein (rNP) of the Crimean-Congo hemorrhagic fever virus (CCHFV) was established by transfection with an expression vector containing the cDNA of CCHFV NP (pKS336-CCHFV-NP). These cells were used as antigens for indirect immunofluorescence (IF) to detect immunoglobulin G antibodies to CCHFV. The sensitivity and specificity of this IF technique were examined by using serum samples and were compared to those of the IF technique using CCHFV-infected Vero E6 cells (authentic antigen). Staining of the CCHFV rNP expressed in HeLa cells showed a unique granular pattern similar to that of CCHFV-infected Vero E6 cells. Positive staining could easily be distinguished from a negative result. All 13 serum samples determined to be positive by using the authentic antigen were also determined to be positive by using CCHFV rNP-expressing HeLa cells (recombinant antigen). The 108 serum samples determined to be negative by using the authentic antigen were also determined to be negative by using the recombinant antigen. Thus, both the sensitivity and the specificity of this IF technique were 100% compared to the IF with authentic antigen. The novel IF technique using CCHFV rNP-expressing HeLa cells can be used not only for diagnosis of CCHF but also for epidemiological studies on CCHFV infections. 相似文献
57.
Generation of functional and mature dendritic cells from cord blood and bone marrow CD34+ cells by two-step culture combined with calcium ionophore treatment 总被引:14,自引:0,他引:14
Liu A Takahashi M Narita M Zheng Z Kanazawa N Abe T Nikkuni K Furukawa T Toba K Fuse I Aizawa Y 《Journal of immunological methods》2002,261(1-2):49-63
The object of this study is to explore a culture method to generate a large number of functional and mature dendritic cells (DC) from human CD34+ hematopoietic progenitor cells. In the present study, we used a two-step method combined with calcium ionophore to induce DC from cord blood (CB) or normal human bone marrow (BM) CD34+ progenitor cells. The two-step method consists of 10 days of first step culture for the expansion and proliferation of CD34+ hematopoietic progenitor cells in the presence of SCF, IL-3, IL-6, G-CSF, and 7--11 days of second step culture for the induction of DC in the presence of GM-CSF, IL-4 and TNF-alpha. By the two-step culture, total nucleated cells were increased 208+/-66 (+/-SD, n=13), or 94+/-29 (n=5)-fold in the culture of CB or BM cells, respectively, compared with the number of CD34+ cells at the time of starting culture. Out of the total nucleated cells, 23 +/-10.4% of cells in CB cell culture and 25 +/-5% of cells in the BM cell culture acquired DC characteristic phenotypes, which were marked expressions of CD1a, HLA-DR, co-stimulatory molecules such as CD80, CD40, and adhesion molecule such as CD58. In allogeneic mixed leukocyte reaction (MLR), two-step cultured cells showed potent allo-stimulatory capacity. With this two-step culture, the absolute number of CD1a+ cells that co-expressed HLA-DR, CD80, CD40 and CD58 was enhanced approximately 3 times in CB cell culture and 1.9 times in BM cell culture, compared with the commonly used one-step culture method for the generation of DC from CD34+ cells using SCF, GM-CSF and TNF-alpha. However, on these DC generated in the two-step culture, the expressions of co-stimulatory molecule CD86 and mature DC marker CD83 were not sufficient. By the treatment of two-step cultured cells with calcium ionophore agent (A23187), the expression of co-stimulatory molecules such as CD86 and CD80 (especially CD86) was up-regulated. Besides, the expression of mature DC marker CD83 was remarkably induced by treatment with A23187 for a short duration (24 h). Consistent with the up-regulation of surface molecules CD86, CD80 and CD83, the two-step cultured cells treated with A23187 also showed a stronger allo-stimulatory capacity compared with the cells without A23187 treatment. In conclusion, the present study demonstrated that the two-step culture method effectively improved the yield of CD1a+ DC generated from CD34+ cells, and the phenotypes and functions of these CD1a+ DC could be enhanced efficiently by treatment with a calcium ionophore agent. 相似文献
58.
Tadao Fukushima Yoji Nagashima Yukio Nakatani Nobuko Nakarnura Kiyoshi Fukasawa Yoshiaki Satomi Ken Yu Yohei Miyagi Ichiro Aoki Kazuaki Misugi 《Pathology international》1994,44(5):401-406
Chromophobe renal cell carcinoma (RCC) is a recently established subtype of RCC, which has rarely been reported in Japan. In this communication, the authors report two Japanese cases of chromophobe RCC together with the immunohistochemical findings. The tumors were composed of sheets and cribriform glands formed by tumor cells with cloudy and reticular cytoplasm. Ultrastructurally, the cytoplasm was filled with numerous microvesicles. The tumor cells were positive for cytokeratin, epithelial membrane antigen, and Tamm-Horsfall protein. Occasionally, LeuM1-positive cells were also noted. Vimentin was negative, unlike the usual RCC. Reactivity for peanut agglutinin was more frequent than that to Lotus tetragonolobus agglutinin. The results of this study suggest that the tumor cellq possessed phenotypes similar to the distal nephron rather than to the proximal tubular cells. 相似文献
59.
Tomoko Morikawa Ichiro Yamadori Takeshi Okino Tetsuro Ogino Masaki Ohmori 《Pathology international》1992,42(4):242-248
Two cell lines designated IC KMS and D KMS were established from human adenovirus type 12 induced tumors of C3Hf/OK mouse. The cell lines retained the characteristics of the original tumor i.e., production of numerous C type and intracisternal A-type particles, integration of Adl2 El region DNA and amplification of the myc gene family. Chromosomal analysis revealed chromosome aberrations in both IC KMS and D KMS cells. The modal chromosome number of IC KMS cells was 54 and that of D-KMS cells was 48. Metacentric chromosomes and mini-chromosomes were found. Trisomy of chromosome 3, 7 and 12 was seen frequently in D KMS cells. Although DNA aneuploidy was revealed by flow cytometry, the DNA indices of these cells showed no relation to the copy number of integrated Adl2 DNA. These cells have been propagated by serial culture during the past 17 months. Production of endogenous virus particles is a unique characteristic of IC KMS and D KMS cells. These cell lines would be useful materials for examining the contribution of Adl2 carcinogenesis to activation of endogenous virus particles, and also the correlation between Adl2 carcinogenesis and cancer related genes. Acta Pathol Jpn 42: 242-248, 1992. 相似文献
60.
Izawa I Nishizawa M Tomono Y Ohtakara K Takahashi T Inagaki M 《Genes to cells : devoted to molecular & cellular mechanisms》2002,7(5):475-485
BACKGROUND: ERBIN, an ErbB2 receptor-interacting protein, belongs to a recently described family of proteins termed the LAP [leucine-rich repeats and PSD-95/dLg-A/ZO-1 (PDZ) domains] family which has essential roles in establishment of cell polarity. RESULTS: To identify new ERBIN-binding proteins, we screened a yeast two-hybrid library, using the carboxyl-terminal fragment of ERBIN containing PDZ domain as the bait, and we isolated p0071 (also called plakophilin-4) as an ERBIN-interacting protein. p0071 is a member of the p120 catenin family, which are defined as proteins with 10 armadillo repeats, and localizes along the cell-cell border. The ERBIN PDZ domain binds the COOH-terminus of p0071 containing the PDZ domain-binding sequence. Endogenous ERBIN was co-immunoprecipitated with p0071. In fully polarized Madin-Darby canine kidney (MDCK) cells, ERBIN co-localized largely with beta-catenin and partly with desmoplakin along the lateral plasma membrane domain. At these cell-cell contact regions, ERBIN co-localizes with p0071. Over-expression of the dominant active forms of Cdc42, Rac1 or RhoA, Rho family small GTPases, resulted in a marked accumulation of ERBIN at the cell-cell contacts of MDCK and HeLa cells. CONCLUSION: These results show that ERBIN interacts in vivo with p0071 and that it may be involved in the organization of adherens junctions and the desmosomes of epithelia. In addition, we demonstrated that the subcellular localization of ERBIN might be regulated by Rho family small GTPases. 相似文献