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121.
Shinohara Y Iwasaki H Ota N Nakajima T Kodaira M Kajita M Shiba T Emi M 《Journal of human genetics》2001,46(1):50-51
The nuclear factor kappa-B 2 (NFKB2) gene is a member of the NFKB/Rel gene family, which is known to be a pivotal regulator of the acute phase of the inflammatory
response and of immune responses. We identified three novel single nucleotide polymorphisms (SNPs) and determined their allelic
frequencies, as determined by the sequencing of 48 alleles of the entire gene in a Japanese population sample. Two of the
three polymorphisms were identified at nucleotide (nt) position 1837 (T/C) and nt position, 1867 (GG/G) in the upstream region
of the gene. The other polymorphism was identified at nt position 2584 (G/T) within intron 1. These polymorphisms will be
useful in genetic studies of the processes involved in inflammatory responses and in bone differentiation.
Received: October 17, 2000 / Accepted: October 23, 2000 相似文献
122.
Thioredoxin suppresses 1-methyl-4-phenylpyridinium-induced neurotoxicity in rat PC12 cells 总被引:7,自引:0,他引:7
Thioredoxin (TRX) is a redox-active protein which plays a cytoprotective role against oxidative stress. Geranylgeranylacetone (GGA), used widely as an anti-ulcer drug, has been reported to induce TRX as well as heat shock protein 70 (HSP70) in hepatocytes and other cells. 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), causes dopaminergic denervation and Parkinsonism in humans. The 1-methyl-4-phenylpyridinium ion (MPP(+)), an active metabolite of MPTP, induces cell death in a rat pheochromocytoma cell line (PC12 cells). We found that MPP(+) suppresses TRX expression in PC12 cells. Overexpression or administration of TRX attenuates MPP(+)-induced neurotoxicity on PC12 cells. Moreover, GGA induces expression of TRX and HSP70 and attenuates MPP(+)-induced toxicity in PC12 cells. These results indicate that TRX and GGA have a possible potential as new therapeutic agents for Parkinson disease. 相似文献
123.
Antifouling blood purification membrane composed of cellulose acetate and phospholipid polymer 总被引:7,自引:0,他引:7
The ideal surface of an artificial blood purification membrane needs hemocompatibility and durability of high performance; it should not adsorb any proteins or cells but should still have high permeability in the desired range of solute size. To improve the anti-fouling property of cellulose acetate (CA) membranes, a CA membrane blended with poly(2-methacryloyloxyethyl phosphorylcholine (MPC)-co-n-butyl methacrylate (BMA)) (PMB30) was designed as a blood purification membrane. The polymer solutions for preparing the membrane were prepared using a solvent mixture composed of N, N-dimethylformamide, acetone, 2-propanol or water. The CA and CA/PMB30 blend membranes with an asymmetric and porous structure were prepared by a phase inversion process.The characteristics of the CA/PMB30 blend membrane, such as structural properties, mechanical properties, and solute permeability were examined with attention to changes in the preparation conditions of the membrane. The CA/PMB30 blend membrane had good water and solute permeability and a sharp molecular weight cut-off property. Moreover, the amount of proteins adsorbed on the CA/PMB30 blend membrane surface was less than that of the original CA membrane and a conventional polysulfone membrane. Adhesion and activation of platelets on the CA/PMB30 blend membrane were reduced compared with that on a CA membrane. In addition, the CA/PMB30 blend membrane showed good permselectivity and an antifouling property during a long time ultrafiltration experiment with protein solutions. 相似文献
124.
Uchida M Kim HM Kokubo T Fujibayashi S Nakamura T 《Journal of biomedical materials research. Part A》2003,64(1):164-170
The apatite-forming ability of titania gels with different structures has been investigated in a simulated body fluid with ion concentrations nearly equal to those of human blood plasma. Titania gels with an amorphous structure or with an anatase or rutile structure were prepared by the sol-gel process with a subsequent heat treatment at various temperatures. The titania gels with an amorphous structure did not induce apatite formation on their surfaces in the simulated body fluid, whereas gels with an anatase or rutile structure induced apatite formation on their surfaces. The deposition of apatite was more pronounced on the anatase gels than on the rutile gels. This indicates that a specific structure of titania is effective in inducing apatite formation in a body environment. Such a specific structure was assumed in this study to be the crystalline planar arrangement in the anatase structure, which facilitates epitaxy of the apatite crystal. 相似文献
125.
The effect of dexamethasone on human mucin 1 expression and antibody-dependent complement sensitivity in a prostate cancer cell line in vitro and in vivo 总被引:4,自引:0,他引:4
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Dexamethasone has been shown to up-regulate human mucin 1 (MUC1) expression in certain types of cancer cell lines in vitro, suggesting that this gluocorticoid may enhance MUC1-based immunotherapies. Here we investigated the effect of dexamethasone on MUC1 expression in the DU145 human prostate cancer cell line in terms of antibody-mediated complement-dependent cell lysis. Cells treated with 1 x 10-8 m dexamethasone in vitro expressed maximal levels of MUC1 after 6 days, with an approximately 3-fold increase over MUC1 levels on untreated cells. DU145 cells were highly resistant to lysis by anti-MUC1 antibody and complement, and their susceptibility to antibody and complement was unaffected by dexamethasone treatment. However, dexamethasone also induced expression of the complement inhibitor decay accelerating factor (DAF) on DU145 cells. Blocking or overcoming the function of DAF resulted in enhanced complement-dependent lysis of dexamethasone-treated cells with anti-MUC1 antibodies, indicating that the failure of dexamethasone to enhance the complement susceptibility of DU145 cells was caused by the up-regulated expression of DAF. We also investigated MUC1 expression in vivo and found that MUC1 expression was significantly up-regulated on tumour cells isolated from immune-deficient mice that had been injected with dexamethasone. However, in contrast to in vitro data, there was no difference between the levels of DAF expressed on tumour-derived DU145 cells isolated from either phosphate buffered saline (PBS)-treated or dexamethasone-treated mice, and tumour cells isolated from dexamethasone-treated mice were more sensitive to complement-mediated lysis. In the broad context of immunotherapy, the in vivo data support the use of dexamethasone as an adjunct treatment. Up-regulated DAF expression would not be a favourable outcome of dexamethasone treatment in terms of complement-dependent antibody therapy, but the in vivo data caution against extrapolation of in vitro data with regard to the modulation of complement inhibitors reported here and elsewhere. 相似文献
126.
To investigate how single neurons in the supplementary eye field (SEF) participate in sequential performance of multiple saccades, we analyzed presaccadic activity while monkeys were performing three saccades in six different orders from memory. The saccades in each sequence were separated by a fixation period and initiated from the same fixation point with intervening return saccades. We found that the majority of the presaccadic activity of the SEF neurons differed significantly depending on the numerical position of saccades in each sequence (rank order). This rank-order selectivity was found in parallel with the selectivity for the sequence of three saccades. Our data suggest a role for SEF neurons in the coding of temporally ordered saccadic eye movements. 相似文献
127.
Yoshitaka Iwasaki Judith Bartlett Kelly MacKay Jennifer Mactavish Janice Ristock 《Journal of community psychology》2008,36(6):702-722
This study reports key findings from a research project, which examined the stress and coping mechanisms of several nondominant groups of individuals. The groups were based in Winnipeg, Manitoba, Canada and included (a) Aboriginal individuals with diabetes, (b) individuals with disabilities, and (c) gays and lesbians. Our analyses of personal narratives and life stories have led to develop an interpretive map of findings that depicts mechanisms of how stress and coping operate. Specifically, the interpretive map consists of personal and structural stressors, meanings of stress, and personal and structural resources, as well as of two constructs termed intersectionality and social exclusion. Not only are nondominant voices and lived experiences recognized and incorporated into an emergent interpretive map, but this map also articulates the complex ways in which multiple identities intersect (i.e., intersectionality) and the realities of being excluded socioeconomically, culturally, and politically among nondominant groups (i.e., social exclusion). © 2008 Wiley Periodicals, Inc. 相似文献
128.
Campylobacter jejuni isolation is the standard for the diagnosis of this type of bacterial infection, but there have been no epidemiological studies of a large number of C. jejuni isolates from patients with Guillain-Barre syndrome (GBS) and Fisher syndrome (FS). For 13 years, stool specimens from GBS/FS patients have been sent from 378 hospitals throughout Japan to the Tokyo Metropolitan Institute of Public Health. A total of 113 strains (11%) were isolated from the stool specimens from 1,049 patients. The isolation rate did not differ by region. The rates were 22% for 449 patients with a history of diarrhea and 2% for the others. An additional 18 isolates were provided by various hospitals. There was no noticeable seasonal distribution in the onset of C. jejuni isolated from patients with GBS/FS. The male/female ratios were 1.7:1 for GBS and 2.2:1 for FS. The patient age range showed a peak in 10- to 30-year-old subjects who had GBS and in 10- to 20-year-old subjects who had FS. The predominance of young adults and male patients who had C. jejuni-associated GBS/FS may be related to the preponderance of young adults and male patients who had C. jejuni enteritis. The median interval from diarrhea onset to neurologic symptom onset was 10 days for GBS/FS. Penner's C. jejuni serotype HS:19 was more frequently present in GBS (67%) than in enteritis (6%) patients. HS:2 was more frequent in FS (41%) than in enteritis (14%) patients. These findings suggest that certain C. jejuni strains specifically trigger GBS and that others specifically trigger FS. 相似文献
129.
Masaki Iwai Yasutaka Ishu Yoshihiro Kitagawa Kazunobu Tada Motomu Kashiwadani Takeshi Okanoue Kei Kashima 《Medical molecular morphology》1993,26(3-4):207-210
The immunoreactivity of albumin (ALB) was observed in the hepatocytes of fetal rats on day 18 of gestation, and was especially observable in immature rough endoplasmic reticulum (rER) and Golgi apparatus (GA); by then, a small amount of silver grains of ALB mRNA could already be detected. Just after birth, immunoreactivity of ALB could be observed in fine granules or diffusely in all hepatocytes, and was present in rER and GA. One week after birth immunoreactivity of ALB was observed in all hepatocytes and was visible in developed rER and GA; the grains of ALB mRNA were present in all hepatocytes. 相似文献
130.