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1.
Takaharu Negoro Kanami Orihara Tomoko Irahara Hiroshi Nishiyama Kanae Hagiwara Risa Nishida Hiroki Takagi Kazue Satoh Yoshiki Yamamoto Shunichi Shimizu Tamio Hagiwara Masakazu Ishii Toshihiro Tanioka Yasuko Nakano Ken Takeda Isao Yoshimura Yoji Iikura Takashi Tobe 《Pediatric allergy and immunology》2006,17(8):583-590
Although many single nucleotide polymorphism (SNP) studies have reported an association of atopy, allergic diseases and total serum immunoglobulin E (IgE) levels, almost all of these studies sought risk factors for the onset of these allergic diseases. Furthermore, many studies have analyzed a single gene and hardly any have analyzed environmental factors. In these analyses, the results could be masked and the effects of other genes and environmental factors may be decreased. Here, we described the correlation between four genes [interleukin (IL)-4 (C-590T), IL-4 receptor (A1652G), FCER1B (G6842A) and STAT6 (G2964A)] in connection with IgE production; the role of IL-10 (C-627A) as a regulatory cytokine of allergy; and the severity of food allergy (FA) and atopic eczema (AE) in 220 Japanese allergic children. In addition to these SNPs, environmental factors, i.e., patient's attitude, indoor environment, and so on, were also investigated in this study. Our study was retrospective, and the correlation was analyzed by our defined clinical scores divided into three terms: worst symptoms, recent symptoms and general amelioration at the most recent examination during the disease course. Our results indicated that IL-10 AA, the genotype with lower IL-10 production, is associated with higher IgE levels in the serum (p < 0.0001, estimate; 0.912). Marginal liver abnormalities were observed in the subject group with both FA and AE (p < 0.1191, estimate; 0.1490). Our defined clinical scores enabled evaluation of various aspects of disease severity. Based on the scores, while no single SNP selected in this study determined severity, the combination of the SNP with laboratory data and environmental factors appeared to determine severity. 相似文献
2.
Osamu Tochikubo Naoki Kura Hiroko Tokita Seiko Sakon Kiyoko Nishijima 《Hypertension research》2006,29(4):233-241
Direct measurement of intra-arterial blood pressure (BP) for 24-h provides approximately 100,000 values that vary enormously, but each (BPi) can be expressed by the equation BPi = BP0 + DeltaBPi (BP0, base BP; DeltaBPi, BP increment, i=1, 2, ..., 100 x 10(3)). About 20% of outpatients with hypertension exhibit white-coat hypertension (WCH). In such patients, DeltaBPc (i = c; c, time at the clinic) is surmised to be large. A method for explaining the physiological factors in DeltaBPc and the estimation of base BP in the outpatient clinic is important. This study addresses this issue. A total of 293 subjects were divided into four groups: 1) WCH group, 45 individuals (office BP > or = 140/90 mmHg and 24-h indirect BP < 125/80 mmHg); 2) normotensive (NT) group, 84 controls matched for age and sex; 3) WHO-I group, 95 hypertensive patients with WHO stage I (office BP > or = 140/90 mmHg and 24-h BP > or = 125/80 mmHg); and 4) WHO-II group, 69 hypertensive patients with WHO stage II. Their BPc and heart rate (HR; HRc, clinic HR) values were measured by a BP-ECG monitoring device in the outpatient clinic. Power-spectral analysis was used to obtain the ratio between the low-frequency component (LF) and high-frequency component (HF) of ECG-RR variability (LF/HF = LH). Twenty-four-hour indirect BP (and BP0) and base HR (HR0) were measured by a portable device (TM2425) at 30-min intervals. Then, DeltaBPc (= BPc - BP0) was estimated by performing linear multivariate analysis applying the model equation DeltaBPc = (BPc -alphaLH)(1-betaHR0/HRc) + epsilon to the above variables (alpha and beta, constant values; epsilon, error). This model equation made it possible to estimate BP0 (and DeltaBPc) with a high coefficient of correlation (r > or = 0.85, mean of error less than 0.82 +/- 5.9 mmHg). The predictive accuracy for discrimination between WCH and sustained hypertension (WHO-I and WHO-II groups) by this equation was 88%. The new DeltaBP-estimation device (BP-ECG monitor) enabled us to infer BP0 and is therefore useful in estimating WCH in the outpatient clinic. 相似文献
3.
Roberto Civitelli M.D. Eturo Ogata Louis V. Avioli Gary Stein Samuel Edelstein John A. Eisman Yasuho Nishii Hajime Orimo Jane Lian Takuo Fujita Yasufumi Hayashi Shigeaki Kato Tadashi Kobayashi Hirotoshi Morii Rikushi Morita Toshitaka Nakamura Yoshiki Seino Masataka Shiraki Tatsuo Suda Naoyuki Takahashi Hideaki Takahashi Tastuhiko Tanisawa Akifumi Tokita 《Calcified tissue international》1995,57(6):409-414
4.
5.
Hirofumi Sawa Tadaki Suzuki Yasuko Orba Yuji Sunden Kazuo Nagashima 《Brain and nerve》2007,59(2):101-108
JC virus (JCV) is a causative agent of progressive multifocal leukoencephalopathy and belongs to Polyomavirus. In this article we describe our recent research relating to this virus. First, JCV's major capsid protein VP1 possesses a nuclear localization signal (NLS) and has the ability to construct a virus-like particle (VLP). We have investigated the mechanism of nuclear entry of JCV using VLP, and clarified the role of NLS. In vitro transport assay revealed that wild type VLP (wtVLP), but not deltaNLSVLP, entered the nuclei of cells. The nuclear transport of wtVLP was dependent on the addition of importins alpha and beta and was prevented by antibodies to nuclear pore complex (NPC). These results suggested that JCV VLP binds to cellular importins via the NLS of VP1 and is transported into the nucleus through the NPC. Second, a yeast two-hybrid screen of a human brain cDNA library demonstrated that the fasciculation and elongation protein zeta 1 (FEZ1) and the heterochromatin protein lalpha (HPla) are proteins that interacted with JCV agnoprotein (Agno). In vitro binding assay showed that Agno interacts directly with FEZ1 and HPlalpha. We have also shown that Agno induces the dissociation of FEZ1 from microtubules and dissociates the interaction between HPlalpha and lamin B receptor. We have demonstrated that interaction between Agno and these host proteins inhibited nuclear egress of JCV. Third, in order to inhibit JCV infection in infected cells, we synthesized siRNA which is specific for JCV Agno. Immunoblotting and immunocytochemical analysis demonstrated that expression levels of agnoprotein and VP1 were significantly inhibited by specific siRNA. In addition, levels of viral mRNAs and viral production were decreased in the cells transfected with Agno siRNA. Furthermore, viral production of cell treated with Agno siRNA was significantly inhibited. These results indicate that post-infection treatment with siRNAs, that targets JCV Agno suppresses virus production in JCV infected cells. Thus, siRNA directed against JCV encoding genes may provide a useful tool for suppression of JCV infection. 相似文献
6.
Mitsuo Miyazawa Takahiro Torii Yasuko Toshimitsu Katsuya Okada Isamu Koyama Yoshito Ikada 《American journal of transplantation》2005,5(6):1541-1547
The aim of this study was to fabricate an artificial bile duct for the development of a new treatment for biliary diseases. Eighteen hybrid pigs were implanted with a bile duct organoid unit (BDOU) made of a bioabsorbable polymer. Twelve of the transplanted BDOUs had been seeded with autologous bone marrow cells (BMCs) in advance. Six animals, the controls, were grafted with the scaffold alone with no BMCs seeded. The common bile duct was cut, the hepatic cut end of the native common bile duct was anastomosed to the BDOU and the other end was anastomosed to the duodenum. The controls underwent a similar operation. The neo-bile duct was removed at pre-determined time points and investigated histologically. All 18 recipient pigs survived until their sacrifice at 6 weeks, 10 weeks or 6 months. Histological examination revealed incomplete epithelialization of the neo-bile duct at 6 weeks and 10 weeks after transplantation. At 6 months, the organoid exhibited a morphology almost identical to that of the native common bile duct. No differences were found between the controls and BMC-seeded pigs. These results show that the artificial bile duct thus fabricated can serve as a substitute for the native bile duct. 相似文献
7.
We previously reported the expression profiles of 9 cytochrome P450 isozymes (CYPs) proteins and those of 40 CYPs genes in pregnant rat's liver, placenta and fetal liver after treatment with pregnenolone-16alpha-carbonitrile (PCN) or phenobarbital (PB). This study was carried out focusing on the gene expression profiles of Phase II drug metabolizing enzymes, Glutathione S-transferase isozymes (GSTs) and UDP-glycosyltransferase isozymes (UDPGTs). Fischer 344 (F344) pregnant rats were daily treated intraperitoneally with 50 mg/kg of PCN or 80 mg/kg of PB from 13 to 16 days of gestation (DG). They were sacrificed on 17 DG, and microarray analysis using Affymetrix Rat Expression Array 230 A was performed. Among 16 GSTs genes examined in this study, 7 genes were significantly induced in dam's liver and 3 genes in fetal liver, respectively, in the PCN-group, while 8 genes were significantly induced in dam's liver and 1 gene in fetal liver, respectively, in the PB-group. On the other hand, among 11 UDPGTs genes examined, 5 genes were significantly induced in dam's liver and 3 genes in fetal liver, respectively, in the PCN-group, while 5 genes were significantly induced in dam's liver and 1 gene in fetal liver, respectively, in the PB-group. There were no significant changes in the placenta of all groups. This is the first report of the gene expression profiles of Phase II drug metabolizing enzymes in pregnant rat and fetal livers and placenta after treatment with typical inducers of drug metabolizing enzymes. 相似文献
8.
Inhibition of BMP-induced ectopic bone formation by an antiangiogenic agent (epigallocatechin 3-gallate) 总被引:3,自引:0,他引:3
Epigallocatechin 3-gallate (EGCG), which is one of the components of green tea, was recently shown to inhibit endothelial cell growth in vitro and angiogenesis in vivo [5]. We have previously shown that bone and cartilage formation by bone morphogenetic protein (BMP) is highly dependent on the geometry of the carrier (vasculature-inducing or -inhibiting geometry [2]. To verify the function of angiogenesis in the BMP induction system, we examine in this article whether inhibition of angiogenesis enhances chondrogenesis and suppresses osteogenesis. Fibrous glass membrane used as a BMP carrier was mixed with 1.2 micrograms rhBMP-2 and 1-10 micrograms of EGCG and was implanted into rats subcutaneously. As the dose of EGCG increased, alkaline phosphatase activity and calcium content were decreased, whereas the type II collagen content was increased. The results clearly indicated that inhibition of vascularization enhanced chondrogenesis and suppressed osteogenesis. 相似文献
9.
Summary The effects of ambient and hypothalamic temperatures were studied on the hyperthermic responses to prostaglandins E1 and E2 (PGE1 and PGE2) injected intraventricularly in the unanesthetized rabbit. Hyperthermic responses to PGE1 observed at different thermal environments were approximately equal in magnitude and time course. However, the prevailing ambient temperature influenced the thermoregulatory mechanisms by which the hyperthermia was achieved. In a hot environment, PGE1-hyperthermia was brought about by suppression of heat loss mechanism with little change in heat production. During cold exposure body temperature was raised mainly by an increase in heat production without a significant change in heat loss. PGEs-hyperthermias were attenuated by warming and enhanced by cooling the anterior hypothalamus. These changes in the hyperthermic responses to PGE1 and PGE2 are in contrast to those obtained with intraventricular injection of noradrenaline at different ambient temperatures and during hypothalamic heating and cooling. It is therefore unlikely that noradrenaline is involved in the hyperthermic responses to PGEs. On the other hand, the results support the view that prostaglandins may be mediators of pyrogen-induced fever. 相似文献
10.
Effects of erythropoietin on glial cell development; oligodendrocyte maturation and astrocyte proliferation 总被引:14,自引:0,他引:14
We investigated the effects of erythropoietin (Epo) in glial cell development, especially the maturation of late stage immature oligodendrocytes and the proliferation of astrocytes. Epo mRNA level in oligodendrocytes was much more prominent than those in neurons or astrocytes, which were the same as those in the young adult kidney, while Epo receptor (Epo-R) mRNA level were almost the same among neural cells, kidney and liver tissues. On immunohistochemical examination, Epo-R expression was also detected in O4-positive immature oligodendrocytes and glial fibrillary acidic protein positive astrocytes. These results suggested that types of both glial cells are responsive to Epo. The numbers of mature oligodendrocytes, which are characterized by myelin basic protein and process development, were increased by treatment with recombinant human Epo (rhEpo) (0.001-0.1 U/ml). The maturation of oligodendrocytes was also enhanced by coculture with astrocytes in vitro. However, when mixed cultured cells (oligodendrocytes+astrocytes) were treated with anti-Epo antibody and/or soluble Epo-R, the differentiation of oligodendrocytes was partially inhibited. Interestingly, high dose rhEpo (1, 3, 10 U/ml) markedly enhanced the proliferation of astrocytes. These results suggested that Epo not only promotes the differentiation and/or maturation in oligodendrocytes, but also enhances the proliferation of astrocytes. It is generally accepted that astrocytes produce Epo, and therefore Epo might act on astrocytes in an autocrine manner. The astrocytes stimulated with Epo may further accelerate the maturation of oligodendrocytes. These comprehensive effects of Epo might also affect the ability of oligodendrocyte lineage cells to promote myelin repair in the normal and damaged adult central nervous system. 相似文献