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41.
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
42.
Nuclear beta-catenin plays crucial roles in the establishment of the embryonic axis and formation of mesendoderm tissues in ascidians and other animals. However, the cue responsible for nuclear accumulation of beta-catenin in the vegetal hemisphere is still unknown in ascidians. Here, we investigated the roles of Wnt5alpha and Dsh in the nuclear accumulation of beta-catenin and activation of its downstream genes in the ascidian Halocynthia roretzi. Wnt5alpha knockdown embryos lost nuclear accumulation of beta-catenin at the 64-cell stage but not at the 32-cell stage, and expression of Hr-lim, one of the targets of beta-catenin, was impaired in the anterior region of the embryo. Zygotic Wnt5alpha expression in the anterior-vegetal blastomeres was primarily responsible for these defects. Dsh knockdown showed no effect on nuclear localization of beta-catenin, but inhibited Hr-lim expression in the posterior region. These results suggest that maintenance of nuclear Hr-beta-catenin after the 64-cell stage is regulated by zygotic Hr-Wnt5alpha, and that expression of its target genes is modulated by both Hr-Wnt5alpha and Hr-Dsh. Our results also highlight the importance of nuclear accumulation of beta-catenin up to the 32-cell stage through a still unclarified mechanism. 相似文献
43.
Yamazaki K McGovern D Ragoussis J Paolucci M Butler H Jewell D Cardon L Takazoe M Tanaka T Ichimori T Saito S Sekine A Iida A Takahashi A Tsunoda T Lathrop M Nakamura Y 《Human molecular genetics》2005,14(22):3499-3506
The inflammatory bowel diseases (IBDs), Crohn's disease (CD) and ulcerative colitis, are chronic inflammatory disorders of the digestive tract. The pathogenesis of IBD is complicated, and it is widely accepted that immunologic, environmental and genetic components contribute to its etiology. To identify genetic susceptibility factors in CD, we performed a genome-wide association study in Japanese patients and controls using nearly 80,000 gene-based single nucleotide polymorphism (SNP) markers and investigated the haplotype structure of the candidate locus in Japanese and European patients. We identified highly significant associations (P = 1.71 x 10(-14) with odds ratio of 2.17) of SNPs and haplotypes within the TNFSF15 (the gene encoding tumor necrosis factor superfamily, member 15) genes in Japanese CD patients. The association was confirmed in the study of two European IBD cohorts. Interestingly, a core TNFSF15 haplotype showing association with increased risk to the disease was common in the two ethnic groups. Our results suggest that the genetic variations in the TNFSF15 gene contribute to the susceptibility to IBD in the Japanese and European populations. 相似文献
44.
45.
Immunohistochemical characteristics of duodenal adenomas in familial adenomatous polyposis with special reference to cell kinetics 总被引:4,自引:0,他引:4
The duodenum is the second most frequent site of cancer in patients with familial adenomatous polyposis (FAP). The main objective of this study was to evaluate the cell kinetics in duodenal and ampullary adenomas in FAP. The endoscopic and biopsy findings of duodenal adenomas in 22 FAP subjects and 18 non-FAP subjects were compared. Adenomas in FAP included 15 ampullary adenomas and 17 nonampullary adenomas. The cell kinetics was evaluated by immunohistochemistry for Ki-67, p53, bcl-2, and cyclooxygenase 2 (COX2), and the apoptotic index (AI) as determined by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL) method. Any correlations between the indices for cell kinetics and the endoscopic findings were identified. All 50 adenomas were histologically verified to be tubular adenoma with low-grade dysplasia. Neither the expression of Ki-67, p53, bcl-2, and COX2 nor the AI differed substantially between FAP and non-FAP subjects. In patients with FAP, duodenal adenoma tended to have a higher Ki-67-labeling index than the ampullary adenoma (54.3 +/- 11.3 versus 46.8 +/- 12.7; .05 < P < .1). In addition, the Ki-67-labeling index in endoscopically normal or slightly enlarged ampullary adenoma was significantly higher than that in markedly enlarged ampullary adenoma (51.8 +/- 11.4 versus 39.4 +/- 11.3; P < .05). Duodenal adenoma in FAP subjects was not found to have a higher proliferative activity or a smaller degree of apoptosis compared with those in non-FAP subjects. The smaller proliferative activity in larger ampullary adenoma may thus be related to the static nature of ampullary adenoma in FAP. 相似文献
46.
Y. Fujimura C. Nishishita J. Uchida M. Iida 《Journal of molecular medicine (Berlin, Germany)》1995,73(2):95-97
We describe a very rare case in which macroamylasemia was associated with ulcerative colitis of total colitis type. The patient's serum amylase isozyme pattern by electrophoresis showed a broad abnormal peak toward the side of the positive pole compared with regular salivary and pancreatic fractions. Sephadex G-200 column chromatography showed a sedimentation coefficient of 6.6 S. Amylase activity was bound to IgG. Double diffusion experiments demonstrated that amylase activity could be precipitated in gel by an antibody to the chain. Although inflammatory bowel disease is occasionally associated with hyperamylasemia due to pancreatitis, we emphasize that, when hyperamylasemia is recognized in patients with inflammatory bowel disease, macroamylasemia also should be considered.Abbreviations
MA
Macroamylasemia
-
UC
Ulcerative colitis
-
IBD
Inflammatory bowel disease 相似文献
47.
48.
Summary The replication in RL-33 cells (rabbit lung cell line) of herpesvirus tamarinus isolated from cotton-topped marmosets(Saguinus oedipus) was investigated by electron microscopy. In the early stages of infection, ring-shaped and granular structures, and fibrillar materials were recognized in the nucleus. Immature particles were often found in such nuclei. The envelope of the virus was formed by budding through intracytoplasmic membranes, the inner nuclear membrane or the membrane of intracytoplasmic vacuoles. Virus particles which appeared to be budding through the plasma membrane were also observed. Aberrant viral forms were produced by independent budding of both the inner and outer nuclear membranes. The mature particles once enveloped acquired a second envelope by budding through intracytoplasmic double membranes or the outer nuclear membrane. Unusual virus-associated structures were observed in the cytoplasm and nucleus. Virus particles appeared to be released by the process of reverse phagocytosis.With 19 Figures 相似文献
49.
K Nagaki K Iida M Okubo S Inai 《International archives of allergy and applied immunology》1978,57(3):221-232
The reaction mechanisms of beta1H were studied. The generation of alternative pathway C3 and C5 convertases on the cell surface as well as in the fluid phase was inhibited by beta1H globulin. The cell preparation bearing the C3b site could bind beta1H with little effect on the C3b hemolytic activity. Bound beta1H was dissociated by the action of C3bINA and C3bINA-treated C3b bearing cell did not bind beta1H anymore. Cell-bound beta1H was also dissociated by the action of B (or Bb). From these and other results, the following conclusions were obtained. The C3b site-bearing cell could bind beta1H on the C3c region of C3b molecules facilitating the C3bINA action on C3b, and beta1H shared the same binding site with B (or Bb) inhibiting the generation of the alternative pathway convertases competitively. 相似文献
50.
Tetsuichiro Inai Akihito Sengoku Eiji Hirose Hiroshi Iida Yosaburo Shibata 《Anatomical record (Hoboken, N.J. : 2007)》2007,290(11):1431-1438
Claudins are integral membrane proteins at tight junctions (TJs) and form TJ strands. In the present study, we found that claudin‐7 was localized along the entire lateral membranes of epididymal epithelium, including the apical junctional region throughout the epididymis, but claudin‐8 was restricted to the apical junctional region. This finding raises the possibility that aberrant TJ strands may be formed on lateral membranes. Thus, we focused on examining whether TJ strands exist on lateral membranes of epididymal epithelium. Freeze‐fracture electron microscopy showed that aberrant TJ strands were observed in only a few principal cells in all segments of the epididymis except for the initial segment, indicating that the occurrence of aberrant strands is very rare. Aberrant TJ strands were smooth and not subdivided into individual particles in the protoplasmic face, and complementary grooves in the extracellular face were almost free of particles. Aberrant TJ strands in the distal caput and corpus epididymis were accompanied by many vesicle‐like structures but those in the proximal caput and cauda epididymis were not. These results suggest that most of claudin‐7 in lateral membranes may exist in a nonpolymerized form and may play some different roles other than the formation of TJ strands, for example, in the formation of a pool of claudin proteins or in the reinforcement of cell adhesion. Anat Rec, 1431‐1438, 2007. © 2007 Wiley‐Liss, Inc. 相似文献