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51.
Masafumi Takahashi Uichi Ikeda Kazuyuki Shimada Tadashi Kasahara Sei-Ichi Kitagawa Yu-Ichi Takahashi Chikao Morimoto Shogo Kano Jun-Ichi Masuyama 《Journal of clinical immunology》1997,17(1):53-62
Interleukin-8 (IL-8) is a chemokine for polymorphonuclear leukocytes (PMNs) and lymphocytes, which promotes the extravasation of these inflammatory cells. In this study, we investigated IL-8 synthesis induced by the adhesive interaction between monocytes and endothelial cells during transmigration and the capacity of transmigrated monocytes to produce IL-8. Cocultured human monocytes and human umbilical vein endothelial cell (HUVEC) monolayers induced the synefgistic production of IL-8, compared with cultures of either monocytes or HUVEC monolayers alone. Coculture-induced IL-8 production almost doubled after HUVECs were stimulated with IL-1. The induced IL-8 mRNA expression was consistent with the protein data, indicating the de novo synthesis of IL-8 by the coculture. Monoclonal antibodies (mAbs) against IL-8 inhibited the transendothelial chemotactic activity of the supernatants for PMNs by 55%. Immunohistochemistry revealed that both adherent and transmigrated monocytes and unstimulated HUVECs expressed IL-8 protein, whereas nonadherent monocytes did little. Transmigrated monocytes spontaneously secreted a 3.8-fold greater amount of IL-8 than the initial monocytes. Coculture-induced IL-8 production was inhibited about 30% by polyclonal Abs against IL-, IL-1, or tumor necrosis factor , while it was not affected by mAbs against intercellular adhesion molecule 1 or vascular cell adhesion molecule 1. The results suggested that adhesive interaction during the transmigration of monocytes through HUVEC monolayers activates both cell types to produce IL-8 and that transmigrated monocytes are capable of producing ample IL-8. 相似文献
52.
I Matsuda N Nagata T Matsuura K Oyanagi K Tada K Narisawa T Kitagawa T Sakiyama F Yamashita M Yoshino 《American journal of medical genetics》1991,38(1):85-89
In a retrospective survey done from 1978-1988 in Japan, 32 male patients with ornithine transcarbamylase (OTC) deficiency were identified. We classified a neonatal and 2 late-onset groups, depending on clinical manifestations and the age at onset; group 1 (0-28 days; N = 10), group 2 (29 days-5 years; N = 13), and group 3 (greater than 5 years; N = 9). Compared to findings in the group 2 patients, there was a higher rate of mortality and a higher incidence of mental retardation in association with a great decrease in enzyme activity in group 1. In group 3, the mortality rate and enzyme activities were similar to those in group 1. However, patients in this group were asymptomatic prior to the first episode. Enzyme activities were measured mostly in autopsy samples. The serum citrulline levels (enzyme product) were highest in this group. Thus, the mutant enzymes were apparently labile with greater activities in vivo than in vitro. Treatments, including a protein-restricted diet, arginine supplementation, and sodium benzoate administration, resulted in a favorable prognosis for survivors with partial enzyme deficiency. We wish to emphasize that the incidence of late onset of this disease is higher than heretofore considered. 相似文献
53.
Kaminaka S Imamura Y Shingu M Kitagawa T Toyoda T 《Journal of virological methods》1999,77(2):117-123
The structural comparison of bovine enterovirus MZ468 strain before and after the heat treatment was studied by ultraviolet resonance Raman (UVRR) spectra excited at both 235 and 251 nm. The difference between full, heated full and purified empty particles, which were expected as an in vitro model of uncoating, were demonstrated. At 235 nm excitation, the Raman bands of the capsid protein dominated in all the UVRR spectra. The UVRR spectra of the empty particles exhibited non-homogenious broadening for tryptophan W3 band and W7 Fermi doublet bands, which were characteristics of hydrophobic environment, when compared with those of the full particles. The results indicates that some Trp indole rings of the full particles were packaged inside the viral capsids and not strained by virion assembly. On the other hand, the Raman bands assigned to guanine residues of the single stranded-RNA genome were enhanced strongly in the 251-nm excited UVRR spectrum. The spectral differences between the packaged (full particles) and the unpackaged virions (heated full particles) indicates that some guanine residues had strong hydrogen bonds in the full particles. 相似文献
54.
Oshitani N Hato F Kitagawa S Maeda K Higuchi K Matsumoto T Arakawa T 《International journal of molecular medicine》2003,11(1):99-104
Isolation of antigenic peptides from the MHC-groove has contributed to the understanding of T cell responses. However, these MHC-associated peptides have been isolated from various murine and human cell lines. The specific antigen responsible for the pathogenesis of inflammatory bowel disease is unknown. We examined antigenic peptides bound to the class II major histocompatibility complex (MHC) groove in human intestine by ion-trap tandem mass spectrometry equipped with online reverse-phase high performance liquid chromatography. We detected 55 parent proteins from 4 controls, 9 patients with ulcerative colitis, and 9 patients with Crohn's disease. The calculated molecular masses (m/z) of these peptides ranged from 874.4 to 2727.4, representing 10-26 amino acid residues. Fifty-one of these 55 parent proteins were exogenous proteins. Escherichia coli-, Saccharomyces cerevisiae-, and Caenorhabditis elegans-derived peptides were found frequently in patients with inflammatory bowel disease. The present results suggest that in vivo antigen processing by antigen-presenting cells and T lymphocytes in human intestine participate with exogenous antigen presentation. Increased immune responses against E. coli, S. cerevisiae and C. elegans found in patients with inflammatory bowel may participate as dysregulated immune responses to enteric flora in the pathogenesis of inflammatory bowel disease. 相似文献
55.
Nagai Y Fujikake N Ohno K Higashiyama H Popiel HA Rahadian J Yamaguchi M Strittmatter WJ Burke JR Toda T 《Human molecular genetics》2003,12(11):1253-1259
Polyglutamine (polyQ) diseases are a growing class of inherited neurodegenerative diseases including Huntington's disease, which are caused by abnormal expansions of the polyQ stretch in each unrelated disease protein. The expanded polyQ stretch is thought to confer toxic properties on the disease proteins through alteration of their conformation leading to pathogenic protein-protein interactions including oligomerization and/or aggregation. Hypothesizing that molecules with selective binding affinity to the expanded polyQ stretch may interfere with the pathogenic properties, we previously identified Polyglutamine Binding Peptide 1 (QBP1) from combinatorial peptide phage display libraries. We show here that a tandem repeat of the inhibitor peptide QBP1, (QBP1)(2), significantly suppresses polyQ aggregation and polyQ-induced neurodegeneration in the compound eye of Drosophila polyQ disease models, which express the expanded polyQ protein under the eye specific promoter. Most importantly, (QBP1)(2) expression dramatically rescues premature death of flies expressing the expanded polyQ protein in the nervous system, resulting in the dramatic increase of the median life span from 5.5 to 52 days. These results suggest that QBP1 can prevent polyQ-induced neurodegeneration in vivo. We propose that QBP1 prevents polyQ oligomerization and/or aggregation either by altering the toxic conformation of the expanded polyQ stretch, or by simply competing with the expanded polyQ stretches for binding to other expanded polyQ proteins. The peptide inhibitor QBP1 is a promising candidate with great potential as a therapeutic molecule against the currently untreatable polyQ diseases. 相似文献
56.
57.
Noguchi M Kitagawa H Michael T Kinoshita K Earashi M Miyazaki I Mizukami W 《Oncology reports》1994,1(1):133-138
We analyzed association between p53 and/or Rb expression and clinicopathologic variables or Ag-NOR counts, and then ascertained whether p53 and/or Rb expression would be useful for estimating prognosis in 81 breast cancer patients. Positive p53 expression was significantly associated with post-menopausal status, axillary lymph node metastases and Ag-NOR counts, whereas low level Rb expression was significantly associated with tumor size. Moreover, the combination of p53 and Rb expression was significantly associated with Ag-NOR counts, although there was no significant association between p53 and Rb expression. In the univariate study, p53 expression as well as age and axillary lymph node metastases were significantly associated with survival, whereas Rb expression was not. In the multivariate study, p53 and/or Rb expression did not provide independent prognostic information, although axillary lymph node metastases was an important factor affecting survival. Our findings suggest that p53 and/or Rb expression may reflect tumor proliferation of breast cancer, but the prognostic value of such assays is limited. 相似文献
58.
Vascular anatomy of the pancreaticoduodenal region: A review 总被引:4,自引:0,他引:4
G. Murakami K. Hirata T. Takamuro M. Mukaiya F. Hata S. Kitagawa 《Journal of Hepato-Biliary-Pancreatic Surgery》1999,6(1):55-68
Vascular anatomy of the pancreaticoduodenal region has been the subject of numerous studies. However, several essential areas
of confusion remain in interpretation of the vascular configuration. We note and discuss three key points in relation to this
confusion: (1) a missing vascular arcade, (2) a rearrangement of the arcade by collateral and/or transverse vessels, and (3)
a solitary vessel without an accompanying comites vein or artery. In addition, we consider that different interpretations
as well as varying reported incidences depend on different "thresholds" when observations are made. Consideration of new aspects
of vascular anatomy of the pancreaticoduodenal region is required for further improvement of surgical procedures. In terms
of the selection of lymph node resection procedure, we discuss mainly the inferior arterial origin. Special attention should
be paid to the ligation of inferior arteries because of the high incidence of the common trunk formation of the upper jejunal
and inferior pancreaticoduodenal arteries. With regard to duodenum-preserving pancreatic head resection for benign tumors,
our observations are introduced in view of either arterial or venous configuration. First, a communicating artery between
the anterior and posterior arterial arcades is noted because of its possible critical role in blood supply to the papilla
of Vater. Second, a venous drainage route from the duodenum to the retroperitoneal space in "normal" specimens is described.
Received for publication on June 17, 1998; accepted on July 27, 1998 相似文献
59.
AS-924, a novel bifunctional prodrug of ceftizoxime. 总被引:5,自引:0,他引:5
M Kasai S Hatano M Kitagawa A Yoshimi H Shirahase K Nishimura N Kakeya 《The Journal of antibiotics》1999,52(5):491-500
To improve the oral absorption of ceftizoxime (CZX), 7beta-[(Z)-2-(2-aminothiazol-4-yl)-2-methoxyiminoacetamido]- 3-cephem-4- carboxylic acid, we synthesized and evaluated a novel series of bifunctional prodrugs, in which L-alanine was introduced into the aminothiazole-oxime moiety at the C-7 position of the various lipophilic esters of CZX. Among these prodrugs, pivaloyloxymethyl 7beta-[(Z)-2-(2-(S)-alanylaminothiazol-4-yl)-2-methoxyiminoa cetamido]-3-cephem-4-carboxylate hydrochloride (ceftizoxime alapivoxil, AS-924) was well absorbed after oral administration in experimental animals and showed potent therapeutic effects in mice infected with gram-positive and gram-negative bacteria. 相似文献
60.
A system in which the retinal tissues of noninbred Wistar rats were used in combination with autoradiography was developed for measurement of DNA repair synthesis in ganglion cells of the central nervous system. Retinal tissues in short-term organ culture were treated with various carcinogens plus tritiated thymidine ([methyl-3H]dThd) or were irradiated with UV light and then treated with [methyl-3H]dThd. Preliminary study with retinal tissues from rats at various ages revealed no age-associated changes in the levels of unscheduled DNA synthesis in ganglion cells. 相似文献