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991.

Objective

This study sought to evaluate associations between sleep time and bicycle accidents, falls under various circumstances, and dental injuries in adolescents.

Methods

A total of 61,696 participants ranging from 12 to 18 years of age who completed the Korea Youth Risk Behavior Web-based Survey (KYRBWS) in 2013 were enrolled in this study. Bicycle riding accidents were analyzed for 17,232 bicycle-riding participants. Data were collected regarding the weekday sleep duration for the most recent 7 days, which was categorized as < 5.5 h, 5.5–6.5 h, 6.5–7.5 h, or ≥ 7.5 h per day, and the incidence of bicycle accidents, slips and falls under various circumstances, and dental injuries in the most recent 12 months. Adjusted odds ratios (aORs) were calculated among sleep groups for bicycle accidents, slips and falls, and dental injuries using simple and multiple logistic regression analyses with complex sampling.

Results

Bicycle riding accidents and slips and falls in classrooms, corridors, the ground, toilets, stairs, and other unspecified situations showed positive correlations with sleep deprivation. Comparisons of groups with ≥ 7.5 h sleep, < 5.5 h, 5.5–6.5 h sleep, and 6.5–7.5 h sleep revealed increased associations with slips and falls under various circumstances. In particular, the aORs were higher in the groups with less sleep (aOR of the 5.5 h group > the 5.5–6.5 h group > the 6.5–7.5 h group). There was no significant relationship between sleep deprivation and dental injury.

Conclusions

This study demonstrated that sleep deprivation among Korean adolescents was associated with bicycle accidents and falls at home and school. Thus, adequate sleep may be needed to prevent accidents and falls.  相似文献   
992.
Cucurbitacin I is a naturally occurring triterpenoid derived from Cucurbitaceae family plants that exhibits a number of potentially useful pharmacological and biological activities. However, the therapeutic impact of cucurbitacin I on the heart has not heretofore been reported. To evaluate the functional role of cucurbitacin I in an in vitro model of cardiac hypertrophy, phenylephrine (PE)-stimulated cardiomyocytes were treated with a sub-cytotoxic concentration of the compound, and the effects on cell size and mRNA expression levels of ANF and β-MHC were investigated. Consequently, PE-induced cell enlargement and upregulation of ANF and β-MHC were significantly suppressed by pretreatment of the cardiomyocytes with cucurbitacin I. Notably, cucurbitacin I also impaired connective tissue growth factor (CTGF) and MAPK signaling, pro-hypertrophic factors, as well as TGF-β/Smad signaling, the important contributing factors to fibrosis. The protective impact of cucurbitacin I was significantly blunted in CTGF-silenced or TGF-β1-silenced hypertrophic cardiomyocytes, indicating that the compound exerts its beneficial actions through CTGF. Taken together, these findings signify that cucurbitacin I protects the heart against cardiac hypertrophy via inhibition of CTGF/MAPK, and TGF- β/Smad-facilitated events. Accordingly, the present study provides new insights into the defensive capacity of cucurbitacin I against cardiac hypertrophy, and further suggesting cucurbitacin I’s utility as a novel therapeutic agent for the management of heart diseases.  相似文献   
993.
IL-17 is a pro-inflammatory cytokine implicated in the pathogenesis of glomerulonephritis and IL-17 deficient mice are protected from nephrotoxic nephritis. However, a regulatory role for IL-17 has recently emerged. We describe a novel protective function for IL-17 in the kidney. Bone marrow chimeras were created using wild-type and IL-17 deficient mice and nephrotoxic nephritis was induced. IL-17 deficient hosts transplanted with wild-type bone marrow had worse disease by all indices compared to wild-type to wild-type bone marrow transplants (serum urea p<0.05; glomerular thrombosis p<0.05; tubular damage p<0.01), suggesting that in wild-type mice, IL-17 production by renal cells resistant to radiation is protective. IL-17 deficient mice transplanted with wild-type bone marrow also had a comparatively altered renal phenotype, with significant differences in renal cytokines (IL-10 p<0.01; IL-1β p<0.001; IL-23 p<0.01), and macrophage phenotype (expression of mannose receptor p<0.05; inducible nitric oxide synthase p<0.001). Finally we show that renal mast cells are resistant to radiation and produce IL-17, suggesting they are potential local mediators of disease protection. This is a novel role for intrinsic cells in the kidney that are radio-resistant and produce IL-17 to mediate protection in nephrotoxic nephritis. This has clinical significance as IL-17 blockade is being trialled as a therapeutic strategy in some autoimmune diseases.  相似文献   
994.
Most of the mitochondrial NADH dehydrogenase subunit 5 (ND5) gene and a part of nuclear 28S ribosomal RNA gene were sequenced for 14 species of ground beetles belonging to the genus Leptocarabus. In both the ND5 and the 28S rDNA phylogenetic trees of Leptocarabus, three major lineages were recognized: (1) L. marcilhaci/L. yokoael/Leptocarabus sp. from China, (2) L. koreanus/L. truncaticollis/L. seishinensis/L. semiopacus/L. canaliculatus/L. kurilensis from the northern Eurasian continent including Korea and Hokkaido, Japan, and (3) all of the Japanese species except L. kurilensis. Clustering of the species in the trees is largely linked to their geographic distribution and does not correlate with morphological characters. The species belonging to different species groups are clustered in the same lineages, and those in the same species group are scattered among the different lineages. One of the possible interpretations of the present results would be that morphological transformations independently took place in the different lineages, sometimes with accompanying parallel morphological evolution, resulting in the occurrence of the morphological species belonging to the same species group (= type) in the different lineages.  相似文献   
995.
A strictly aerobic Gram-positive, moderately halophilic spore forming bacterium, designated strain SL6-1T, was isolated from a salt lake in Xin-jiang province, China. Growth of strain SL6-1T was observed at NaCl concentrations of 0∼20% (w/v) (the optimum being 5∼7%, w/v). The peptidoglycan type of strain SL6-1T was Alγ-meso-diaminopimelic acid and its major cellular fatty acids were iso-C14:0 and iso-C16:0 and ante-iso-C15:0. The major respiratory isoprenoid quinone was MK-7 and the G+C content of the genomic DNA was 44.5 mol%. The major cellular phospholipids were phosphatidylglycerol and diphosphatidylglycerol. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain SL6-1T formed a phylogenetic lineage within the genus Virgibacillus. Based on 16S rRNA gene sequence similarity, the strain was most closely related to Virgibacillus olivae E308T, Virgibacillus kekensis YIM kkny16T, Virgibacillus marismortui DSM 12325T with 97.1%, 97.1%, and 97.0% gene sequence similarities, respectively and the sequence similarities to other related taxa were less than 96.7%. The DNA relatedness values between strain SL6-1T and V. olivae E308T, V. kekensis YIM kkny16T, V. marismortui DSM 12325T were 16.7%, 51.0%, and 22.8%, respectively. On the basis of physiological, biochemical and phylogenetic properties, strain SL6-1T represents a novel species, for which the name Virgibacillus xinjiangensis sp. nov. is proposed. The type strain is SL6-1T (=KCTC 13128T =DSM 19031T).  相似文献   
996.
Pellet size of white rot fungus, Pleurotus ostreatus may affect the secretion of its degradative enzymes and accompanying biodegrading capability, but could be controlled by several physical culture conditions in liquid culture. The pellet size of P. ostreatus was affected by the volume of inoculum, flask, and medium, but the agitation speed was the most important control factor. At the lower agitation speed of 100 rpm, the large pellets were formed and the laccase activity was higher than that of small pelleted culture at 150 rpm, which might be due to loose intrapellet structure. However, the biodegradation rates of benzylbutylphthalate and dimethylphthalate were higher in the small pelleted culture, which indicated the involvement of other degradative enzyme rather than laccase. The activity of esterase which catalyzes the nonphenolic compounds before the reaction of ligninolytic enzymes was higher in the small pelleted culture, and coincided with the degradation pattern of phthalates. This study suggests the optimization of pellet morphology and subsequent secretion of degradative enzymes is necessary for the efficient removal of recalcitrants by white rot fungi.  相似文献   
997.
Bacillus subtilis was cultivated to high cell density for nattokinase production by pH-stat fed-batch culture. A concentrated mixture solution of glucose and peptone was automatically added by acid-supplying pump when culture pH rose above high limit. Effect of the ratio of glucose to peptone in feeding solution was investigated on cell growth and nattokinase production by changing the ratio from 0.2 to 5 g glucose/g peptone. The highest cell concentration was 77 g/L when the ratio was 0.2 g glucose/g peptone. Cell concentration decreased with increasing the ratio of glucose to peptone in feeding solution, while the optimum condition existed for nattokinase production. The highest nattokinase activity was 14,500 unit/mL at a ratio of 0.33 g glucose/g peptone, which was 4.3 times higher than that in batch culture.  相似文献   
998.
Chung HK  Kim SW  Byun SJ  Ko EM  Chung HJ  Woo JS  Yoo JG  Lee HC  Yang BC  Kwon M  Park SB  Park JK  Kim KW 《BMB reports》2011,44(10):686-691
Granulocyte colony-stimulating factor (G-CSF) is a cytokine secreted by stromal cells and plays a role in the differentiation of bone marrow stem cells and proliferation of neutrophils. Therefore, G-CSF is widely used to reduce the risk of serious infection in immunocompromised patients; however, its use in such patients is limited because of its non-persistent biological activity. We created an N-linked glycosylated form of this cytokine, hG-CSF (Phe140Asn), to assess its biological activity in the promyelocyte cell line HL60. Enhanced biological effects were identified by analyzing the JAK2/STAT3/survivin pathway in HL60 cells. In addition, mutant hG-CSF (Phe140Asn) was observed to have enhanced chemoattractant effects and improved differentiation efficiency in HL60 cells. These results suggest that the addition of N-linked glycosylation was successful in improving the biological activity of hG-CSF. Furthermore, the mutated product appears to be a feasible therapy for patients with neutropenia.  相似文献   
999.
Ahn KS  Kim YJ  Kim M  Lee BH  Heo SY  Kang MJ  Kang YK  Lee JW  Lee KK  Kim JH  Nho WG  Hwang SS  Woo JS  Park JK  Park SB  Shim H 《Theriogenology》2011,75(5):933-939
Animals with a targeted disruption of genes can be produced by somatic cell nuclear transfer (SCNT). However, difficulties in clonal selection of somatic cells with a targeted mutation often result in heterogeneous nuclear donor cells, including gene-targeted and non-targeted cells, and impose a risk of producing undesired wildtype cloned animals after SCNT. In addition, the efficiency of cloning by SCNT has remained extremely low. Most cloned embryos die in utero, and the few that develop to term show a high incidence of postnatal death and abnormalities. In the present study, resurrection of an alpha-1,3-galactosyltransferase (αGT) gene-targeted miniature pig by recloning using postmortem ear skin fibroblasts was attempted. Three cloned piglets were produced from the first round of SCNT, including one stillborn and two who died immediately after birth due to respiratory distress syndrome and cardiac dysfunction. Among the three piglets, two were confirmed to be αGT gene-targeted. Fibroblasts derived from postmortem ear skin biopsies were used as nuclear donor cells for the second round of SCNT, and a piglet was produced. As expected, PCR and Southern analyses confirmed that the piglet produced from recloning was αGT gene-targeted. Currently, the piglet is fourteen months of age, and no overt health problems have been observed. Results from the present study demonstrate that loss of an invaluable animal, such as a gene-targeted miniature pig, may be rescued by recloning, with assurance of the desired genetic modification.  相似文献   
1000.
Kim E  Yoon SJ  Kim EY  Kim Y  Lee HS  Kim KH  Lee KA 《PloS one》2011,6(10):e25870
The COP9 (constitutive photomorphogenic) signalosome (CSN), composed of eight subunits, is a highly conserved protein complex that regulates processes such as cell cycle progression and kinase signalling. Previously, we found the expression of the COP9 constitutive photomorphogenic homolog subunit 3 (CSN3) and subunit 5 (CSN5) changes as oocytes mature for the first time, and there is no report regarding roles of COP9 in the mammalian oocytes. Therefore, in the present study, we examined the effects of RNA interference (RNAi)-mediated transient knockdown of each subunit on the meiotic cell cycle in mice oocytes. Following knockdown of either CSN3 or CSN5, oocytes failed to complete meiosis I. These arrested oocytes exhibited a disrupted meiotic spindle and misarranged chromosomes. Moreover, down-regulation of each subunit disrupted the activity of maturation-promoting factor (MPF) and concurrently reduced degradation of the anaphase-promoting complex/cyclosome (APC/C) substrates Cyclin B1 and Securin. Our data suggest that the CSN3 and CSN5 are involved in oocyte meiosis by regulating degradation of Cyclin B1 and Securin via APC/C.  相似文献   
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