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91.
Yoshihiko Takahashi Yuichi Takiguchi Takayuki Kuriyama Tadaaki Miyamoto 《Clinical & experimental metastasis》1998,16(2):149-157
A clone of NIH3T3 transformant (H3) can yield subcutaneous tumors and experimental pulmonary metastasis in nude mice. Compared
to H3 in culture, the cells after in vivo tumor growth (H3-N) acquired enhanced tumorigenicity and metastatic ability. Also, indirect immunofluorescence revealed that
cellular fibronectin (c-FN) of H3-N was decreased remarkably. We have studied the interactions between H3 and extracellular
matrices to elucidate these phenomena. In the present study, we observed the effect of NIH3T3, H3, and H3-N cultured in type
I collagen gel. Morphologically in the collagen gel, NIH3T3 assumed an extensive elongated fiber-like shape, H3 assumed a
moderately elongated shape, and H3-N assumed a round or spindle shape with short pseudopodia. Compared to conventional cultures
on dishes, cell proliferation of all three types was suppressed in collagen gel, but the degree of the suppression was least
in H3-N. As a result, H3-N grew fastest in collagen gel. The variants which acquired growth advantage in the subcutaneum of
mice also kept it in collagen gel. H3 cells were cultured in type I collagen gel for 4 weeks, a period comparable to that
of tumor formation in nude mice. The cells after this long-term culture (H3-C) acquired enhanced tumorigenicity and metastatic
ability nearly equal to that of H3-N. FACS analysis revealed that the c-FN of H3-C had decreased to a value comparable to
that of H3-N. This means that type I collagen gel as well as subcutaneous tissues could select variants of H3 with less c-FN
through proliferation. Moreover, it is suspected that lattices of type I collagen regulate cell proliferation of fibroblast
via c-FN.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
92.
Cloning and characterization of the cDNA encoding the HA protein of a hemagglutination-defective measles virus strain 总被引:3,自引:0,他引:3
Hiroyuki Saito Hiroyasu Sato Mariko Abe Seizaburo Harata Ken-Ichi Amano Tsunehisa Suto Morihiro Morita 《Virus genes》1994,8(1):107-113
cDNA clones corresponding to the mRNA for the hemagglutinin of the hemagglutination-defective strain AK-1 of measles virus were isolated and characterized. Compared with the prototype Edmonstron strain, 60 nucleotide substitutions that resulted in 18 amino acid changes were detected. An additional potential N-linked glycosylation site was added by point mutation, which was supported by the observation that the hemagglutinin of the AK-1 strain was stained more heavily after NaDodSO4PAGE and periodic acid-Schiff (PAS) staining than the Edmonston strain. Computer-assisted analysis revealed that three reverse turns in the secondary structure had disappeared in the hemagglutinin of the AK-1 strain. Moreover, one of these structural changes occurred in the closely glycosylated region at amino acid residues 168–240, which appeared to be a biologically important functional domain. The isoelectric point calculated from the predicted amino acid sequence became about 1 pH unit more basic in the AK-1 strain than the Edmonston strain. This present study is the first sequence analysis of the hemagglutinin gene in a hemagglutination-defective strain of the measles virus. 相似文献
93.
Four hundred and sixty-five male and 159 female consecutive autopsy cases of lung cancer, autopsied over the 27 years from 1958 to 1984, were analysed and were compared with other materials and mortality statistics, including statistics from other countries. Malignant tumor autopsy cases are gradually increasing and now comprise more than 60% of total autopsy cases. The percentage of lung cancer cases among all autopsy cases was 7% in males and 4% in females. The percentage of lung cancer in autopsies of patients with malignancies was about 13% for males and 9% for females. The most frequent fatal malignant tumors were gastric cancer, lung cancer, and leukemia. The relative incidence of gastric cancer was decreasing, while that of lung cancer was increasing. In the distribution of the histological types of lung cancer, adenocarcinomas were the most frequent types in both sexes. As has been noted in mortality statistics, we noticed a gradual shift in the peak age of lung cancer autopsy cases towards older patients. During the period under study, the peak shifted from patients in their sixties to patient in their seventies; this was true for most of the major histological types in both sexes. The male/female ratio of all lung cancer cases was 2.9, which was much lower than the ratio found in the United States and Europe, and very similar to the ratio of the mortality rates in Japan and other Asian countries. It was pointed out that the male/female ratios by age-group in each country is a very good reflection of the histological distribution. 相似文献
94.
Adjuvant Activity of 6-Amino-6-Deoxy-Muramyldipeptides and Their Acylamino Derivatives on the Induction of Delayed Hypersensitivity to Azobenzenearsonate-N-Acetyl-l-Tyrosine in Guinea Pigs 下载免费PDF全文
Ichiro Azuma Hiroyuki Okumura Ikuo Saiki Yoshiro Tanio Makoto Kiso Akira Hasegawa Yuichi Yamamura 《Infection and immunity》1981,32(3):1305-1308
The 6-amino-6-deoxy-N-acetylmuramyldipeptides and their 6-acylamino derivatives were shown to be active as adjuvants on the induction of delayed-type hypersensitivity to azobenzenearsonate-N-acetyl-l-tyrosine in guinea pigs. However, 6-acylamino-6-deoxy-N-(acyl)muramyldipeptides were inactive as adjuvants. 相似文献
95.
Autopsy cases of lung cancer, 41,988 in males and 13,818 in females, consecutively registered between 1958 and 1987, were analysed statistically and compared with other case materials and mortality statistics. Cases of malignant tumor showed a gradual increase, and now comprise 60% of the total male and 55% of the total female autopsy cases. The percentage of lung cancer cases among the total autopsy cases was 9% for males and 5% for females. The percentage of lung cancer cases among total cases of malignant tumor was about 17% for males and 9% for females. Among fatal malignant tumors, gastric cancer and lung cancer showed the highest frequency. The relative incidence of gastric cancer was seen to decrease, whereas that of lung cancer increased. Of the histological types of lung cancer in both sexes, adenocarcinoma was the most frequent, followed by squamous cell carcinoma. During the period studied the peak age of patients with lung cancer shifted from the seventh to eighth decade, and a significant elevation of mean age was demonstrated for all of the major histological types in both sexes. The male:female ratio for all lung cancer cases was 3.0, which was much lower than those for the United States and Europe, but very similar to the ratios of mortality statistics in Japan and other Asian countries. As a result of a previous autopsy study at the University of Tokyo, it was also confirmed that the male:female ratio relative to age in each country reflects very well the histological distribution. 相似文献
96.
Takusa Y Fukao T Kimura M Uchiyama A Abo W Tsuboi Y Hirose S Fujioka H Kondo N Yamaguchi S 《Molecular genetics and metabolism》2002,75(3):227-234
Very-long-chain acyl-CoA dehydrogenase (VLCAD) deficiency is clinically classified into severe, intermediate, and myopathic forms. We identified mutations in three unrelated Japanese patients with VLCAD deficiency: two with the myopathic form and one with the intermediate form, all compound heterozygotes of K264E/M437V, A416T/1798delA, and P89S/IVS16-3delAA, respectively. We characterized four missense mutations, K264E, M437V, A416T, and P89S, by transisent expression analysis, using SV40-transformed fibroblasts derived from a VLCAD-null patient, as recipient cells. In transient expression of the wild-type VLCAD cDNA, VLCAD activity at 30 degrees C was higher than at 37 degrees C. Moreover, this temperature-sensitive character is more evident in all the mutant proteins tested than in wild type. Based on characterization of the five missense mutations identified in four Japanese patients, including data on one patient with the myopathic form previously reported, patients with the nonsevere forms (intermediate or myopathic forms) have missense mutations with residual activities in at least one allele. Expression analysis at 30 degrees C may be more useful for evaluating these missense mutations, compared with that at 37 degrees C. 相似文献
97.
Nishioji K Okanoue T Itoh Y Narumi S Sakamoto M Nakamura H Morita A Kashima K 《Clinical and experimental immunology》2001,123(2):271-279
To clarify the role of IP-10 in autoimmune liver diseases, we studied the serum levels of IP-10 in 14 patients with autoimmune hepatitis (AIH), 23 patients with primary biliary cirrhosis (PBC), and 65 patients with chronic viral hepatitis (20 type B and 45 type C). The hepatic expression of IP-10 mRNA and the correlation between the serum levels of IP-10 and clinical parameters were also evaluated. In addition to 20 healthy controls, 16 rheumatoid arthritis (RA) patients were included as an extrahepatic inflammatory disease. The serum level of IP-10 was significantly (P < 0.02) higher in patients with AIH, PBC, and chronic hepatitis B and C than in healthy controls, and it was significantly correlated (P < 0.05) with the serum levels of aspartate aminotransferase and alanine aminotransferase in patients with AIH, PBC, and chronic hepatitis B and C. The serum level of IP-10 was not elevated in RA patients. After successful treatment of AIH and chronic hepatitis C, the serum level of IP-10 decreased to the same level as in healthy volunteers. As we previously showed in cases with chronic hepatitis B or C, in situ hybridization in both AIH and PBC cases demonstrated the expression of IP-10 mRNA in hepatocytes around focal or lobular necrosis surrounded by infiltrating mononuclear cells, whereas IP-10 mRNA was not expressed in areas around the damaged bile ducts in PBC cases. The present results suggest that IP-10 is specifically produced by hepatocytes in inflammatory areas irrespective of the aetiology of hepatitis, and that IP-10 may help to recruit T cells to the hepatic lesions in autoimmune liver diseases as well as in chronic viral hepatitis. 相似文献
98.
Yuji Narita Hideaki Kagami Hiroshi Matsunuma Yosuke Murase Minoru Ueda Yuichi Ueda 《Journal of artificial organs》2008,11(2):91-99
Previous attempts to create small-caliber vascular prostheses have been limited. The aim of this study was to generate tissue-engineered small-diameter vascular grafts using decellularized ureters (DUs). Canine ureters were decellularized using one of four different chemical agents [Triton-X 100 (Tx), deoxycholate (DCA), trypsin, or sodium dodecyl sulfate (SDS)] and the histology, residual DNA contents, and immunogenicity of the resulting DUs were compared. The mechanical properties of the DUs were evaluated in terms of water permeability, burst strength, tensile strength, and compliance. Cultured canine endothelial cells (ECs) and myofibroblasts were seeded onto DUs and evaluated histologically. Canine carotid arteries were replaced with the EC-seeded DUs (n = 4). As controls, nonseeded DUs (n = 5) and PTFE prostheses (n = 4) were also used to replace carotid arteries. The degree of decellularization and the maintenance of the matrix were best in the Tx-treated DUs. Tx-treated and DCA-treated DUs had lower remnant DNA contents and immunogenicity than the others. The burst strength of the DUs was more than 500 mmHg and the maximum tensile strength of the DUs was not different to that of native ureters. DU compliance was similar to that of native carotid artery. The cell seeding test resulted in monolayered ECs and multilayered alpha-smooth muscle actin-positive cells on the DUs. The animal implantation model showed that the EC-seeded DUs were patent for at least 6 months after the operation, whereas the nonseeded DUs and PTFE grafts become occluded within a week. These results suggest that tissue-engineered DUs may be a potential alternative conduit for bypass surgery. 相似文献
99.
Susumu Harada Maya Iijima Akiko Nakamura Yoshitsugu Yoshizaki Hiroaki Matsuo Eisin Morita 《Arerugī》2007,56(1):41-48
BACKGROUND: Either omega-5 gliadin or high molecular weight glutenin is known to be a major allergen in wheat-dependent exercise-induced anaphylaxis (WDEIA). It is generally considered that gluten specific IgE score is more reliable than that of wheat specific IgE score for the diagnosis of WDEIA. Our aim was to verify the significance of gluten specific IgE in the diagnosis of WDEIA. METHODS: We evaluated the result of gluten CAP-RAST score and omega-5 gliadin specific IgE score on four WDEIA patients who visited our hospital during the years 2004 and 2005, whose diagnosis were onfirmed by prick tests, immunoblot tests and provocation tests. RESULTS: Contrary to our expectations, all four patients showed negative gluten CAP-RAST scores, however all patient's omega-5 gliadin specific IgE scores were positive. CONCLUSION: Our results suggest that gluten specific CAP-RAST score is unreliable in the diagnosis of WDEIA. On the other hand omega-5 gliadin specific IgE score is possibly a better candidate as a diagnostic tool for WDEIA. 相似文献
100.
Yuichi Takeoka Shao-Yuan Chen Richard L. Boyd Koichi Tsuneyama Nobuhisa Taguchi Shinji Morita Hisashi Yago Seishi Suehiro Aftab A. Ansari Leonard D. Shultz M. Eric Gershwin 《Clinical & developmental immunology》1997,5(2):79-89
It is widely accepted that the thymic microenvironment regulates normal thymopoiesis
through a highly coordinated and complex series of cellular and cytokine interactions. A direct
corollary of this is that abnormalities within the microenvironment could be of etiologic
significance in T-cell-based diseases. Our laboratory has developed a large panel of
monoclonal antibodies (mAbs) that react specifically with epithelial or nonepithelial
markers in the thymus. We have taken advantage of these reagents to characterize the
thymic microenvironment of several genetic strains of mice, including BALB/cJ,
C57BL/6J, NZB/BlnJ, SM/J, NOD/Ltz, NOD/Ltz-scid/sz, C57BL/6J-Hcph
me/Hcph me, and
ALY/NscJcl-aly/aly mice, and littermate control animals. We report herein that control
mice, including strains of several backgrounds, have a very consistent phenotypic profile
with this panel of monoclonal antibodies, including reactivity with thymic epithelial cells
in the cortex, the medulla and the corticomedullary junction, and the extracellular matrix.
In contrast, the disease-prone strains studied have unique, abnormal staining of thymic cortex
and medulla at both the structural and cellular levels. These phenotypic data suggest
that abnormalities in interactions between developing thymocytes and stromal cells characterize
disease-prone mice. 相似文献