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71.
Arisawa T Tahara T Shibata T Nagasaka M Nakamura M Kamiya Y Fujita H Nakamura M Yoshioka D Arima Y Okubo M Hirata I Nakano H 《Journal of clinical immunology》2008,28(1):44-49
We investigated the association between ulcerative colitis (UC) and polymorphisms of IL-17A (rs2275913, G-197A) and IL-17F
(rs763780, 7488T/C) genes. We employed the multiplex PCR-SSCP method to detect gene polymorphisms. Both the numbers of -197A
(IL-17A) and 7488T (IL-17F) alleles were significantly correlated to the development of UC. The frequencies of -197A/A and
7488T/T genotypes in the UC group were significantly higher than those in the non-UC group. An adjusted analysis revealed
that -197A and 7488T alleles were independent risk factors for the developing UC. In addition, both polymorphisms were significantly
associated with the pancolitis phenotype. Furthermore, -197A allele was significantly correlated to the chronic relapsing
phenotype and -197A/A homozygote was more frequent in steroid-dependent cases, whereas 7488T allele was correlated with the
chronic continuous phenotype. Our results provided the first evidence that -197A (IL-17A) and 7488T (IL-17F) alleles may influence
the susceptibility to and pathophysiological features of UC independently. 相似文献
72.
73.
We recently proposed a new psychostimulant animal model of the progressive pathophysiological changes of schizophrenia. Studies using that model produced a treatment strategy for preventing progression. Lamotrigine (LTG) blocks repeated high-dosage methamphetamine (METH)-induced initiation and expression of prepulse inhibition deficit and development of apoptosis in the medial prefrontal cortex (mPFC). Moreover, it inhibits METH-induced increases in extracellular glutamate levels in the mPFC (Nakato et al., 2011, Neurosci. Lett.). Abnormal behavior induced by METH or NMDA receptor antagonists is regarded as an animal model of schizophrenia. This study examined the effects of LTG on the development of behavioral sensitization to METH and cross-sensitization to dizocilpine (MK-801) by repeated administration of high-dose METH (2.5 mg/kg, 10 times s.c.). Rats were injected repeatedly with LTG (30 mg/kg) after 120 min METH administration (2.5 mg/kg). Repeated co-administration of LTG blocked the development of behavioral cross-sensitization to MK-801 (0.15 mg/kg), but it did not prevent behavioral sensitization to METH (0.2 mg/kg). The LTG-induced prevention of increased glutamate by high-dose METH might be related to the former finding. Combined results of our previous studies and this study suggest that LTG is useful to treat schizophrenia, especially at a critical point in its progression. 相似文献
74.
Nahoko Nishimoto Yoichi Imai Koki Ueda Masahiro Nakagawa Akihito Shinohara Motoshi Ichikawa Yasuhito Nannya Mineo Kurokawa 《International journal of hematology》2010,92(1):194-197
Familial platelet disorder (FPD) is a rare autosomal dominant disorder which causes moderate thrombocytopenia with or without impaired platelet function. Patients have a propensity to develop acute myeloid leukemia (AML), and various types of second hits have been postulated in the evolution to AML. However, only a few cases of acute lymphoblastic leukemia (ALL) have been reported thus far. Here, we report a family of FPD with a germ-line hemi-allelic mutation R174X in the RUNX1 gene. The proband of the family developed AML and her son had ALL of the T cell lineage. The balanced translocation t(1;7)(p34.1;q22) was detected in the lymphoblasts from the patient with ALL. This translocation was not seen in any other affected members of the family or in the bone marrow sample of this patient in complete remission. Taken together, t(1;7)(p34.1;q22) is thought to be one of the somatic second hits that predisposes FPD to acute leukemia with T cell phenotype. 相似文献
75.
Koki Haruyama Atsutoshi Yoshimura Mariko Naito Mami Kishimoto Mikio Shoji Yoshimitsu Abiko Yoshitaka Hara Koji Nakayama 《Infection and immunity》2009,77(10):4414-4420
Porphyromonas gingivalis is a major periodontal pathogen that has the pathogenic proteinases Arg-specific gingipain and Lys-specific gingipain. We previously found that a cell surface component on P. gingivalis is able to induce Toll-like receptor 2 (TLR2)- and TLR4-independent signaling in 7.19 cells and that this component can be degraded by gingipains. In this study, we purified this component from the P. gingivalis gingipain-null mutant KDP136 and obtained two candidate proteins. Matrix-assisted laser desorption ionization-time-of-flight mass spectrometry analysis showed that the proteins, with molecular masses of 123 and 43 kDa, were encoded by PGN_0748 and PGN_0728 (pgm6), respectively, in the P. gingivalis ATCC 33277 genome sequence. The PGN_0748-encoded protein, which we refer to as gingipain-sensitive ligand A (GslA), reacted with antiserum that could effectively inhibit the activity of KDP136 to induce NF-κB activation in 7.19 cells, but Pgm6 did not. To further determine what protein is responsible for the NF-κB activation, we constructed gslA, pgm6, and pgm6 pgm7 deletion mutants from KDP136. When 7.19 cells were exposed to those mutants, the gslA deletion mutant did not induce NF-κB activation, whereas the pgm6 and pgm6 pgm7 deletion mutants did. Furthermore, NF-κB activation in 7.19 cells induced by KDP136 was partially inhibited by antiserum against a recombinant protein expressed from the 5′-terminal third of gslA. These results indicate that GslA is one of the factors that induce NF-κB activation in 7.19 cells. Interestingly, the gslA gene was present in four of seven P. gingivalis strains tested. This restricted distribution might be associated with the virulence potential of each strain.Porphyromonas gingivalis is an anaerobic gram-negative bacterium that is frequently isolated from advanced periodontal lesions (25). The number of P. gingivalis cells is closely associated with the depth of periodontal pockets and is significantly reduced after treatment (7). Thus, this organism is thought to play an important role in the development and progression of periodontitis.P. gingivalis has two major cysteine proteinases, Arg-specific gingipain and Lys-specific gingipain. These proteinases have been reported to cleave various host immune effector molecules, such as immunoglobulin G (IgG) and IgM (22); several cytokines and cytokine receptors (1, 2, 10, 11, 17); and a pattern recognition receptor, CD14 (21, 23). These modifications of host immune regulatory molecules enable P. gingivalis to escape from the host immune system. This activity of gingipain seems to play an important role in the colonization of P. gingivalis in the oral cavity.Besides degradation of the host molecules, we previously found that gingipains could degrade a ligand expressed on the P. gingivalis cell surface (8). A CHO cell-derived nuclear factor (NF)-κB reporter cell line, 7.19, was stimulated with wild-type (ATCC 33277) and gingipain-deficient P. gingivalis (KDP136) bacterial cells. Since bacterial cells possess a number of ligands for Toll-like receptor 2 (TLR2) and TLR4, 7.19 cells, which lack both TLR2- and TLR4-signaling pathways, enable analysis of TLR2- and TLR4-independent signaling (18). Interestingly, 7.19 cells were activated by gingipain-null mutant KDP136 but not by its parental strain ATCC 33277, suggesting that the ligand of P. gingivalis was degraded by gingipains in the wild-type bacterial cells. In fact, the ability of KDP136 to induce activation of NF-κB in 7.19 cells was diminished after treatment of the bacterial cells with gingipains. In a previous study (8), we partially purified components with the ability to activate NF-κB in 7.19 cells from KDP136. The activities of the components were also diminished by treatment with gingipains.The aim of the present study was to purify and identify the gingipain-sensitive ligand from gingipain-deficient P. gingivalis cells. We tried further purification and obtained two proteins encoded by protein-coding sequence (CDS) PGN_0748 and CDS PGN_0728 (pgm6) in the P. gingivalis ATCC 33277 genome sequence (14). We then constructed CDS mutants from KDP136 and determined which protein is responsible for the activity that induces NF-κB activation in 7.19 cells. 相似文献
76.
Ratana Tacharoenmuang Satoshi Komoto Ratigorn Guntapong Sompong Upachai Phakapun Singchai Tomihiko Ide Saori Fukuda Kriangsak Ruchusatsawast Busarawan Sriwantana Masashi Tatsumi Kazushi Motomura Naokazu Takeda Takayuki Murata Somchai Sangkitporn Koki Taniguchi Tetsushi Yoshikawa 《Journal of medical virology》2020,92(2):174-186
Group A rotavirus (RVA) is a major cause of acute gastroenteritis in infants and young children worldwide. This study aims to clarify the distribution of G/P types and genetic characteristics of RVAs circulating in Thailand. Between January 2014 and September 2016, 1867 stool specimens were collected from children and adults with acute gastroenteritis in six provinces in Thailand. RVAs were detected in 514/1867 (27.5%) stool specimens. G1P[8] (44.7%) was the most predominant genotype, followed by G3P[8] (33.7%), G2P[4] (11.5%), G8P[8] (7.0%), and G9P[8] (1.3%). Unusual G3P[9] (0.8%), G3P[10] (0.4%), G4P[6] (0.4%), and G10P[14] (0.2%) were also detected at low frequencies. The predominant genotype, G1P[8] (64.4%), in 2014 decreased to 6.1% in 2016. In contrast, the frequency of G3P[8] markedly increased from 5.5% in 2014 to 65.3% in 2015 and 89.8% in 2016. On polyacrylamide gel electrophoresis, most (135/140; 96.4%) of the G3P[8] strains exhibited a short RNA profile. Successful determination of the nucleotide sequences of the VP7 genes of 98 G3P[8] strains with a short RNA profile showed that they are all equine-like G3P[8] strains. On phylogenetic analysis of genome segments of two representative Thai equine-like G3P[8] strains, it was noteworthy that they possessed distinct NSP4 genes, one bovine-like and the other human-like. Thus, we found that characteristic equine-like G3P[8] strains with a short RNA electropherotype are becoming highly prevalent in children and adults in Thailand. 相似文献
77.
During a surveillance study (November 2001-March 2005), one rare G15P[11] and two rare G15P[21] bovine group A rotavirus strains were detected in diarrhoeic calves in Eastern India. Sequence analysis of the VP8*, VP6, NSP4 and NSP5 genes of the G15P[11] strain confirmed its bovine origin. Although the NSP4 and NSP5 genes of the two G15P[21] strains were of bovine origin, their VP6 genes shared higher nucleotide and amino acid identities with simian strain SA11 (92.5-93.1% and 98.5-98.7%) than bovine strains (88.5-88.9% and 97-97.2%), and by phylogenetic analysis, exhibited clustering with SA11, distantly related to bovine strains. All these pointed towards a possible reassortment event of VP6 gene between bovine and simian (SA11-like) strains. Therefore, the present study provided molecular evidence for bovine origin of G15 strains and revealed a rare instance of genetic diversity in the bovine VP6 gene, otherwise conserved in group A rotavirus strains from cattle. 相似文献
78.
Lin YP Chang SY Kao CL Huang LM Chung MY Yang JY Chen HY Taniguchi K Tsai KS Lee CN 《Journal of clinical microbiology》2006,44(10):3686-3694
Since the mid-1990s, novel G9 rotaviruses have been detected in many countries, suggesting that G9 is a globally important serotype. The molecular epidemiology of G9 rotaviruses in Taiwan from 2000 to 2002 was investigated in this study. G9 rotavirus first appeared in 2000 with 4 cases and constituted 33.8% and 54.8% of the rotavirus-positive samples in 2001 and 2002, respectively. These G9 strains belonged to P[8]G9, subgroup II, and long electropherotype, except one belonged to P[4]G9, subgroup II, and short electropherotype. Nucleotide sequencing and phylogenetic analysis of 52 Taiwanese G9 rotaviruses showed that the VP7 genes shared a high degree of identity to overseas G9 rotaviruses detected after 1993 and that the VP8* portions of the VP4 genes were more closely related to those of local rotaviruses of other G types. The two P[8]G9 strains with high nucleotide identities in the VP7 and the partial VP4 genes, 01TW591 of Taiwan from 2001 and 95H115 of Japan from 1995, varied in four genes, genes 2, 3, 7, and 8, which was revealed by RNA-RNA hybridization. Representative strains for different RNA patterns were also analyzed in the partial VP2 and VP3 genes; the nucleotide identities were high between Taiwanese G9 strains and local G3 or G2 strains. These results suggested that Taiwanese G9 rotaviruses possibly had evolved through reassortment between overseas G9 strains and circulating rotaviruses of other G types. 相似文献
79.
Tomomitsu Tahara Tomoyuki Shibata Masakatsu Nakamura Hiromi Yamashita Daisuke Yoshioka Masaaki Okubo Naoko Maruyama Toshiaki Kamano Yoshio Kamiya Hiroshi Fujita Yoshihito Nakagawa Mitsuo Nagasaka Masami Iwata Kazuya Takahama Makoto Watanabe Hiroshi Nakano Ichiro Hirata Tomiyasu Arisawa 《Clinical and experimental medicine》2009,9(2):125-130
Tryptase acting at protease-activated receptor 2 (PAR2) contributes to the pathogenesis of Inflammatory bowel diseases (IBDs).
DNA methylation has been shown to be an important mechanism in gene silencing. We attempted to clarify the relationship between
the promoter methylation of PAR2 and ulcerative colitis (UC). 84 UC patients enrolled in the study. UC patients were classified
by disease behavior, severity and extent of disease. For rectal inflammatory mucosal specimens from all the patients, and
normal terminal ileum from 23 patients, promoter methylation of PAR2 gene was quantified by digital densitographic analysis
following to methylation-specific polymerase chain reaction (MSP). The mean methylation levels of the PAR2 gene in all 84
subjects was 38.4 ± 19.6%. Although mean methylation levels in rectal inflammatory mucosa, and paired normal terminal ileum
did not vary, methylation levels of PAR2 gene was significantly higher in total colitis than rectal colitis (total colitis
vs. rectal colitis; 42.9 ± 19.6% vs. 34.5 ± 18.9%, P = 0.046). The higher methylation levels were also associated with Steroid-dependent (P = 0.002) and refractory (P = 0.007) UC. Our data suggest that PAR2 methylation status in rectal mucosa correlates with more severe disease phenotypes
of UC. 相似文献
80.
Yoshito Arisawa Erika Sutanto-Ward Rory R. Dalton Elin R. Sigurdson 《Journal of surgical oncology》1994,56(2):75-80
This study evaluates tumor response, survival, and development of resistance to HAI chemotherapy, comparing a combination of bolus MMC and short duration FUdR to short duration FUdR alone or to long duration FUdR alone, using a rat hepatic metastases model. After intrasplenic injection of 107 K12/TRb colon cancer cells in BD-IX rats on day 0, hepatic metastases were evaluated and HA catheters were placed on day 14. The response was determined on day 28. Chemosensitivity of the hepatic metastases after HAI treatments was determined using the MTT assay. Bolus MMC with short duration FUdR as well as long-term FUdR alone provided better hepatic tumor response and survival than short-term FUdR alone. However, bolus MMC with short duration FUdR decreased the acquired resistance to FUdR, compared to long-term FUdR, without causing resistance to MMC. These results provide a rationale for using short duration of FUdR in combination with other drugs. © 1994 Wiley-Liss, Inc. 相似文献