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991.
The Epidemiological Study of Autism in Fukushima-ken 总被引:1,自引:0,他引:1
Yoshihiko Hoshino M.D. Hisashi Kumashiro M.D. Yuko Yashima M.D. Ryuichi Tachibana M.D. Makoto Watanabe M.D. 《Psychiatry and clinical neurosciences》1982,36(2):115-124
Abstract: A survey of children aged under 18 years in Fukushima-ken (prefecture) in Japan showed that 2.33 per 10,000 children suffered from early infantile autism. The average of prevalence rates of autistic children born between 1968 and 1974 was 4.96 per 10,000 children. Based on a comparison between cities and rural districts, the prevalence rates of the former were significantly higher than those of the latter. Autistic boys outnumbered autistic girls with a sex ratio of 9: 1. Psychiatric illnesses; were very rare among the relatives of autistic children. The rate of prenatal and perinatal complications was higher than the national norm among autistic children. Parents of autistic children had a significantly higher education than the national norm. There were more nuclear families in the autistic group than in the national norm. 相似文献
992.
Horimoto T Takada A Fujii K Goto H Hatta M Watanabe S Iwatsuki-Horimoto K Ito M Tagawa-Sakai Y Yamada S Ito H Ito T Imai M Itamura S Odagiri T Tashiro M Lim W Guan Y Peiris M Kawaoka Y 《Vaccine》2006,24(17):3669-3676
The pandemic threat posed by highly pathogenic H5N1 influenza A viruses has created an urgent need for vaccines to protect against H5 virus infection. Because pathogenic viruses grow poorly in chicken eggs and their virulence poses a biohazard to vaccine producers, avirulent viruses produced by reverse genetics have become the preferred basis for vaccine production. Here, we investigated two key characteristics of potential H5 vaccine candidates: the hemaggutinin (HA) cleavage site sequence and its modification to attenuate virulence and the choice of background virus to provide a high-growth rate. We produced recombinant (6:2 reassortant) viruses that possessed a series of modified avirulent-type HA and neuraminidase genes, both of which were derived from an H5N1 human isolate. The other genes of these recombinant viruses were derived from donor virus strains known to grow well in eggs: the human strain A/Puerto Rico/8/34 (PR8) or an avian strain. All of the recombinant viruses grew well in eggs, were avirulent in chicks, and protected animals against infection with a wild-type virus. However, one of the recombinant viruses with an avian virus background acquired a mutation in the HA cleavage site sequence that conferred virulence potential to this virus. Moreover, vaccine candidates with the avian virus background were more virulent than those with the human virus background. We conclude that 6:2 recombinant viruses with a PR8 background are more suitable than those with an avian virus background for vaccine development and that the HA cleavage site sequence must be modified to minimize the potential for a vaccine virus to convert to a virulent form. 相似文献
993.
Miwa N Nakamura T Naruse Y Ooe Y Ohno Y 《[Nihon kōshū eisei zasshi] Japanese journal of public health》2006,53(7):493-503
PURPOSES: To analyze the outcomes of measures designed to decrease cerebrovascular diseases (CVDs) in Japan and to project CVD mortality trends into the 21st century based on an analysis of rates observed in the 20th century. METHODS: The numbers of CVD deaths and population sizes from 1920 to 2003 (excluding 1940 to 1946) by sex, year, and 5-year age group (from 20 to 79 years old) were used and effects of various factors on CVD mortality rates were estimated using Nakamura's Bayesian age-period-cohort model. The numbers of CVD deaths up to the year 2050 were projected based on estimates of age, cohort, and future period effects under three scenarios: (i) values remaining constant after year 2003; (ii) linearly extrapolated values; and (iii) quadratically extrapolated values, we obtained using a regression line for period effects from 1995 to 2003. RESULTS: The age, cohort, and period effects on CVD mortality rates were large and in order of the magnitude of their ranges. There were small differences between males and females. The age effect increased with aging and the period effect started decreasing after 1970. The cohort effect was high for birth cohorts born from the 1840s to the 1890s and low for those born from the 1920s to the 1970s. There were some differences in the cohort effect between males and females for birth cohorts born after 1940s; for females there was a gradual decrease, while for males there was a slight increase, after which it remained almost constant. According to the three scenarios, CVD deaths: (i) had upward trends through the projected period and peaked at around 2025 and 2045; (ii) remained almost constant at the present level for males, and decreased slightly for females; (iii) decreased for both males and females. CONCLUSIONS: The outcomes of measures designed to decrease CVDs were observed as period effects after 1970. Exposure to these measures is associated with prevention of CVD deaths. Nevertheless, in the first half of the 21st century, the number of CVD deaths is projected to increase due to the aging of the baby boomers and upward trends in the cohort effect for males. It would be necessary to adopt and develop both population strategies to decrease future period effects and high-risk strategies to decrease cohort effects for younger males who are currently in their twenties and thirties. 相似文献
994.
Inducible nitric oxide synthase inhibitors abolished histological protection by late ischemic preconditioning in rat retina 总被引:7,自引:0,他引:7
Sakamoto K Yonoki Y Kubota Y Kuwagata M Saito M Nakahara T Ishii K 《Experimental eye research》2006,82(3):512-518
Brief ischemia was reported to protect retinal cells against injury induced by subsequent ischemia-reperfusion with de novo protein synthesis, and this phenomenon is known as late ischemic preconditioning. The aims of the present study were to determine whether nitric oxide synthase (NOS) was involved in the mechanism of late ischemic preconditioning in rat retina using pharmacological tools. Under anesthesia with pentobarbital sodium, male Sprague-Dawley rats were subjected to 60 min of retinal ischemia by raising intraocular pressure to 130 mm Hg. Ischemic preconditioning was achieved by applying 5 min of ischemia 24 hrs before 60 min of ischemia. Retinal sections sliced into 5 microm thick were examined 7 days after ischemia. Additional groups of rats received NG-nitro-L-arginine and NG-monomethyl-L-arginin, non-selective NO synthase inhibitors, 7-nitroindazole, a neuronal NOS inhibitor, and aminoguanidine and L-N6-(1-iminoethyl) lysine, inducible NO synthase (iNOS) inhibitors before preconditioning, and were subjected to 60 min of ischemia. In the non-preconditioned group, cell loss in the ganglion cell layer and thinning of the inner plexiform and inner nuclear layer were observed 7 days after 60 min of ischemia. Ischemic preconditioning for 5 min completely protected against the histological damage induced by 60 min of ischemia applied 24 hrs thereafter. Treatment of rats with aminoguanidine and L-N6-(1-iminoethyl) lysine, but not NG-nitro-L-arginine, NG-monomethyl-L-arginine or 7-nitroindazole, wiped off the protective effect of ischemic preconditioning. The inhibitory effect of aminoguanidine was abolished by L-arginine, but not D-arginine. The results in the present study suggest that NO synthesized by iNOS is involved in the histological protection by late ischemic preconditioning in rat retina. 相似文献
995.
Ochiai T Nishimura K Noguchi H Kitajima M Tsuruoka Y Takahashi Y Tsukada A Watanabe E Nagaoka I Futagawa S 《Journal of surgical oncology》2006,94(1):45-50
BACKGROUND AND OBJECTIVES: Phosphoribosylation of 5-fluorouracil (5-FU) is an essential step which leads to tumor growth inhibition and orotate phosphoribosyl transferase (OPRT) is the main enzyme that involves in this conversion of 5-FU to 5-fluorouridine monophosphate. This retrospective study was aimed to evaluate the correlation between tumor OPRT activity and the clinical outcome in colorectal cancer (CRC) patients treated by oral 5-FU-based adjuvant chemotherapy. METHODS: Surgical specimen was obtained from resectable 124 CRC patients who were subsequently treated by oral 5-FU-based adjuvant chemotherapy. OPRT activity in the extract of tumor tissue was enzymatically determined. The cut-off value of intratumor OPRT activity against disease free survival was determined by maximal chi2 method. The disease free survival and overall survival in each group were calculated using the Kaplan-Meier method. RESULTS: Patients were divided into two groups by determined cut-off value of intratumor OPRT (0.147 nmol/min/mg protein) (high group: n = 102, low group: n = 22). Five-year DFS (P = 0.035) and OS (P = 0.020) were significantly better for high OPRT group. CONCLUSIONS: This study demonstrated that an assay of tumor OPRT contributes to the determination of 5-FU-based adjuvant chemotherapy outcome and application in clinical practice should be included in tumor analysis prior to 5-FU-based adjuvant chemotherapy. 相似文献
996.
Yang X Lu P Ishida Y Kuziel WA Fujii C Mukaida N 《International journal of cancer. Journal international du cancer》2006,118(2):335-345
The liver parenchyma is populated by hepatocytes and several nonparenchymal cell types, including Kupffer cells and hepatic stellate cells. Both Kupffer cells and hepatic stellate cells are responsive to the chemokine CCL2, but the precise roles of CCL2 and these cells in liver tumor formation remain undefined. Hence, we investigated the effects of the lack of the major CCL2 receptor, CCR2, on liver tumor formation induced by intraportal injection of the murine colon adenocarcinoma cell line, colon 26. Wild-type mice showed macroscopic tumor foci in the liver 10 days after injection of colon 26 cells. After 10 days, CCL2 proteins were detected predominantly in tumor cells, coincident with increased intratumoral macrophage and hepatic stellate cell numbers. Although tumor formation occurred at similar rates in wild-type and CCR2-deficient mice up to 10 days after tumor cell injection, the number and size of tumor foci were significantly attenuated in CCR2-deficient mice relative to wild-type mice thereafter. Moreover, neovascularization and matrix metalloproteinase 2 expression were diminished in CCR2-deficient mice with a concomitant reduction in the accumulation of macrophages and hepatic stellate cells. Furthermore, matrix metalloproteinase 2 was detected predominantly in hepatic stellate cells but not in macrophages. We provided the first definitive evidence that the absence of CCR2-mediated signals can reduce the trafficking of hepatic stellate cells, a main source of matrix metalloproteinase 2, and consequently can diminish neovascularization during liver tumor formation. 相似文献
997.
Miyauchi A Gotoh M Kamioka H Notoya K Sekiya H Takagi Y Yoshimoto Y Ishikawa H Chihara K Takano-Yamamoto T Fujita T Mikuni-Takagaki Y 《Journal of bone and mineral metabolism》2006,24(6):498-504
We propose that specific osteocyte–matrix interactions regulate the volume-sensitive calcium influx pathway, which we have
shown is mediated by stretch-activated cation channels (SA-Cat) and is essential for the stretch-activated anabolic response
in bone. The current study measured the hypotonic swelling-induced increase in cytosolic calcium concentration, [Ca2+]i, in rat osteocytes, and found that cells adherent to different matrices behave differently. Osteopontin and vitronectin,
matrix molecules that bind the αVβ3 integrin, induced larger responses to the hypotonic swelling than other matrix molecules that bind other integrins. Addition
of echistatin, which is a soluble αVβ3 ligand, significantly enhanced the hypotonic [Ca2+]i increase in addition to inducing an immediate increase in [Ca2+]i by itself. These results strongly support the contention that αVβ3 integrin signaling in osteocytes interacts with that in mechanotransduction, which is downstream of SA-Cat. 相似文献
998.
We have previously demonstrated that parathyroid hormone-related protein (PTHrP) is a cachexia inducer, but it is still not
known what PTHrP effects on target tissues induce the cachexia. Therefore, we examined the effects of anti-PTHrP antibody
and osteoprotegerin (OPG) on PTHrP-producing tumor-induced cachexia. Nude mice bearing PTHrP-producing human lung cancer cells
(HARA-B) exhibited cachexia with hypercalcemia 3–4 weeks after inoculation, accompanied by losses in body, adipose tissue,
and muscle weight. OPG ameliorated hypercalcemia, as did neutralization of PTHrP with antibody; and it increased both body
and adipose tissue weights. These increases in body and adipose tissue weight, however, were significantly less than those
in mice treated with anti-PTHrP antibody. Simultaneous administration of OPG and anti-PTHrP antibody caused significant increases
in body, adipose tissue, and muscle weight, along with an immediate decrease in blood ionized calcium levels. The increase
in body weight was similar to that observed in mice treated with anti-PTHrP antibody alone, and the decrease in the blood
ionized calcium levels was significantly greater than that in mice treated with OPG or anti-PTHrP antibody alone. These results
suggest that an effect of PTHrP on target tissues other than hypercalcemia is involved in the development of cachexia. Expression
of cachexia-inducing proinflammatory cytokines (interleukin-6 and leukemia inhibitory factor) is stimulated by PTHrP. This
might be a mechanism by which PTHrP produces tumor-induced cachexia. It is also suggested that OPG and anti-PTHrP antibody
synergistically act to ameliorate hypercalcemia, although the mechanism responsible for this is unclear. 相似文献
999.
Either hepatic resection, microwave coagulonecrotic therapy (MCN), or a combination of liver resection and MCN was performed in 166 patients with liver metastases from colorectal cancer. In 53 patients who underwent liver resection, the 1-, 3-, and 5-year actual survival rates were 85.0%, 51.2%, and 42.2%, respectively. In 77 who underwent MCN, the 1-, 3-, and 5-year actual survival rates were 82.8%, 46.7%, and 36.0%, respectively. In 34 who underwent both liver resection and MCN, the 1-, 3-, and 5-year actual survival rates were 84.2%, 41.6%, and 21.1%, respectively. The survival rates among the three groups did not differ significantly. Of 166 patients with liver metastases, 44 showed multiple liver metastases (H3). Of 44 patients with multiple liver metastases, 27 underwent MCN (mean tumor diameter 27.2 mm, mean number of tumors 11.2), and the 1-, 3-, and 5-year actual survival rates were 73.1%, 31.3%, and 25.1%, respectively. Of 44 patients with multiple liver metastases, 17 underwent both liver resection and MCN (mean tumor diameter 41.9mm, mean number of tumors 8.1), and the 1-, 3-, and 5-year actual survival rates were 66.3% and 14.7%, respectively. To perform MCN more effectively in the treatment of liver metastases, surgical margins around tumors should be from 10 mm to 15 mm, and both the feeding artery and drainage vein should be coagulated before MCN. 相似文献
1000.
Ando Y Terao Y Yamashita K Fujinaga A Tanabe T Fukusaki M 《Masui. The Japanese journal of anesthesiology》2006,55(7):897-899
BACKGROUND: In burn patients, microvascular permeability is increased. It is difficult to decide the time to administer albumin because it may induce pulmonary edema in the re-filling period. One report shows that microalbuminuria is correlated with endothelial injury and systemic microvascular permeability. METHODS: We measured urinary albumin/creatinine ratio (ACR) in 4 burn patients for 48 hours after injury. RESULTS: In all patients, ACR was elevated in the early period after injury. Moreover, ACR in 2 severe burn patients with burn total body area of over 30% was above the normal range. CONCLUSIONS: The present results show that ACR seems to be correlated with the level of microvascular permeability in 4 burn patients. We conclude that ACR may be a useful indicator to decide the time to administer albumin to a burn patient. However, further investigation is required to decide the threshold value of ACR in a severe burn patient whose ACR are kept above the normal range in the long-term. 相似文献