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71.
《Saudi Journal of Biological Sciences》2020,27(7):1781-1787
A look into the associations of socioeconomic status (SES) with prevalence of various complications in sickle cell disease (SCD) is necessary, for an improvement of societal norms, governmental health policies and strategies. We therefore studied the influence of SES indices on certain hematological and clinical parameters in children with SCD in Saudi Arabia. We included 32 female and 33 male patients aged 5–16 years, who were classified based upon their family income. Family monthly income was divided into 4 categories from lowest to highest, with socioeconomic class1 having low earnings of <5000 SAR; the middle income class divided further into class 2 with earnings >5000–10,000 SAR, and class 3 with earnings >10,000–15,000 SAR; and the higher income class 4 with earnings of >15,000 SAR. The assessment indices used were, the frequency of vaso-occlusive crisis (VOC), adverse events, and hematological parameters. A higher percentage of children affected with the disease were from class1, which is the low socio-economic class. It was found that the percentage of frequency of VOC pain crisis, and adverse events was higher in social class 1 patients than in the classes 2, 3, and 4. Also, the age group 5–10 years appeared more susceptible to adverse events and VOC. Our findings suggest the need to conduct future larger studies, to deduce the modifying influence of disparity in SES on certain clinical and hematological indices in children with SCD. 相似文献
72.
73.
The purpose of this study was to examine undergraduate music education and performance alumni's career path, retrospective institutional satisfaction, and financial status. Data for this study were drawn from respondents from the 2010 administration of the nationwide, multi-institutional survey conducted by the Strategic National Arts Alumni Project (SNAAP). Regarding career path, nearly half of the music performance degree graduates reported performing as their current job, and slightly more than half of the music education degree graduates reported working in K–12 schools. Participants were generally satisfied with their institutional experiences, although relatively low levels of satisfaction were reported for networking and career advising services. The respondents reported being most satisfied with aspects of their current jobs that reflected the intrinsic benefits of contributing to a greater good, satisfying personal interests and values, and opportunities to be creative. The majority of the sample reported accruing student loan debt ranging between $10,000 and $30,000; however, no significant differences were found between groups, and 40 percent of the participants reported having accrued no debt at all. The reported annual income of the participants varied significantly, with music educators reporting higher earnings than performers. 相似文献
74.
Hideo Otaki 《Marine and Freshwater Behaviour and Physiology》2013,45(4):195-269
Demersal fish resources in the East China and Yellow Seas were reviewed. A current and historical survey of the fishery was made. The distribution and migration of demersal fish were characterized, and an assessment of fishery resources was provided. The standardization of fishing efforts and resources management were also examined. 相似文献
75.
《Free radical research》2013,47(11-12):1245-1266
AbstractThe intestinal tract, known for its capability for self-renew, represents the first barrier of defence between the organism and its luminal environment. The thiol/disulfide redox systems comprising the glutathione/glutathione disulfide (GSH/GSSG), cysteine/cystine (Cys/CySS) and reduced and oxidized thioredoxin (Trx/TrxSS) redox couples play important roles in preserving tissue redox homeostasis, metabolic functions, and cellular integrity. Control of the thiol-disulfide status at the luminal surface is essential for maintaining mucus fluidity and absorption of nutrients, and protection against chemical-induced oxidant injury. Within intestinal cells, these redox couples preserve an environment that supports physiological processes and orchestrates networks of enzymatic reactions against oxidative stress. In this review, we focus on the intestinal redox and antioxidant systems, their subcellular compartmentation, redox signalling and epithelial turnover, and contribution of luminal microbiota, key aspects that are relevant to understanding redox-dependent processes in gut biology with implications for degenerative digestive disorders, such as inflammation and cancer. 相似文献
76.
Su-Min Lee Sin Young Park Seoung Woo Shin In Sup Kil Eun Sun Yang 《Free radical research》2013,47(2):165-173
Staurosporine induces the production of reactive oxygen species, which play an important causative role in apoptotic cell death. Recently, it was demonstrated that the control of cellular redox balance and the defense against oxidative damage is one of the primary functions of cytosolic NADP+-dependent isocitrate dehydrogenase (IDPc) by supplying NADPH for antioxidant systems. The present report shows that silencing of IDPc expression in HeLa cells greatly enhances apoptosis induced by staurosporine. Transfection of HeLa cells with an IDPc small interfering RNA (siRNA) markedly decreased activity of IDPc, enhancing the susceptibility of staurosporine-induced apoptosis reflected by DNA fragmentation, cellular redox status and the modulation of apoptotic marker proteins. These results indicate that IDPc may play an important role in regulating the apoptosis induced by staurosporine and the sensitizing effect of IDPc siRNA on the apoptotic cell death of HeLa cells offers the possibility of developing a modifier of cancer chemotherapy. 相似文献
77.
《Free radical research》2013,47(8):1-2
Methamphetamine (METH)-induced neurotoxicity is associated with mitochondrial dysfunction and enhanced oxidative stress. The aims of the present study conducted in the mouse brain repetitively treated with METH were to (1) examine the redox status using the redox-sensitive imaging probe 3-methoxycarbonyl-2,2,5,5-tetramethylpiperidine-1-oxyl (MCP) and (2) non-invasively visualize the brain redox status with electron paramagnetic resonance (EPR) imaging. The rate of reduction of MCP was measured from a series of temporal EPR images of mouse heads, and this rate was used to construct a two-dimensional map of rate constants called a “redox map.” The obtained redox map clearly illustrated the change in redox balance in the METH-treated mouse brain that is a known result of oxidative damage. Biochemical assays also showed that the level of thiobarbituric acid-reactive substance, an index of lipid peroxidation, was increased in mouse brains by METH. The enhanced reduction in MCP observed in mouse brains was remarkably suppressed by treatment with the dopamine synthase inhibitor, α-methyl-p-tyrosine, suggesting that enhancement of the reduction reaction of MCP resulted from enzymatic reduction in the mitochondrial respiratory chain. Furthermore, magnetic resonance imaging (MRI) of METH-treated mice using a blood–brain barrier (BBB)-impermeable paramagnetic contrast agent revealed BBB dysfunction after treatment with METH for 7 days. MRI also indicated that the impaired BBB recovered after withdrawal of METH. EPR imaging and MRI are useful tools not only for following changes in the redox status and BBB dysfunction in mouse brains repeatedly administered METH, but also for tracing the drug effect after withdrawal of METH. 相似文献
78.
Mark A. Fraker 《人类与生态风险评估》2013,19(1):28-52
During 1985–1990, two groups of killer whales in Prince William Sound, Alaska, experienced unusually high rates of mortality, while seven others did not. Those affected were AB pod, part of the southern Alaska population of resident (fish-eating) killer whales, and the AT1 transient (marine mammal–eating) group, a very small, reproductively isolated population that last reproduced in 1984. In 1985–1986, several AB pod members were shot by fishermen defending their catch from depredation, which explains some of the deaths. Understanding the other deaths is complicated by the Exxon Valdez oil spill (March 1989) and uncertainties about the causes and times of the deaths. For AB pod, possible factors involved in the post-spill mortalities are delayed effects of bullet wounds, continued shooting, oil exposure, and consequences of being orphaned. For the AT1 group, possible factors are oil exposure, small population size, old age, and high-contaminant burdens. An analysis of possible effects of inhalation of volatile organic compounds, contact with the oil slick, and ingestion of oil with water or prey did not reveal route(s) of exposure that could explain the mortalities. The cause(s) of the killer whale deaths recorded following the oil spill remain uncertain. 相似文献
79.
Lovasoa Rina Raharinaivo Henitsoa Jaonalison Jamal Mahafina Dominique Ponton 《Zeitschrift fur angewandte Ichthyologie》2020,36(4):402-413
In order to provide biological evidence of the real impact of mosquito seine nets in southwestern Madagascar, an efficient procedure for determining the size at maturity of small-sized tropical fishes was developed. The fishes caught by two small-scale fishermen were studied between October 2017 and April 2018. One catch per day was analyzed three days per month during the full-moon period. In the laboratory, fishes were all sorted by morphospecies, photographed and measured. One individual per morphospecies was selected for being identified using CO1 DNA barcoding. A total of 34,051 individual fishes belonging to 144 DNA bacoded species from 48 families was obtained from 42 samples, 467 individuals from 22 morphospecies that had not been successfully barcoded were excluded from the analyses. The macroscopic observations of 8,143 individuals between 0.7 and 10 cm SL indicated the proportion of individuals with clearly observable gonads was 15% only.Among the 144 species identified via DNA barcoding, 83 consisted of individuals that were all without clearly observable gonads, seven of individuals that were all with clearly observable gonads and 54 included of individuals with and without clearly observable gonads. As the determination of L50 using logistic general linear models failed for most species, the minimum size at maturity was retained to determine the proportion of juveniles and adults for these 54 species. Compared to the data available in FishBase, the minimum size at maturity appears more adequate to discrimine juvenile from adult fish of small-sized tropical species. 相似文献
80.
Tanja Proctor Katrin Jensen Meinhard Kieser 《Biometrical journal. Biometrische Zeitschrift》2020,62(3):777-789
Individualized therapies for patients with biomarkers are moving more and more into the focus of research interest when developing new treatments. Hereby, the term individualized (or targeted) therapy denotes a treatment specifically developed for biomarker-positive patients. A network meta-analysis model for a binary endpoint combining the evidence for a targeted therapy from individual patient data with the evidence for a non-targeted therapy from aggregate data is presented and investigated. The biomarker status of the patients is either available at patient-level in individual patient data or at study-level in aggregate data. Both types of biomarker information have to be included. The evidence synthesis model follows a Bayesian approach and applies a meta-regression to the studies with aggregate data. In a simulation study, we address three treatment arms, one of them investigating a targeted therapy. The bias and the root-mean-square error of the treatment effect estimate for the subgroup of biomarker-positive patients based on studies with aggregate data are investigated. Thereby, the meta-regression approach is compared to approaches applying alternative solutions. The regression approach has a surprisingly small bias even in the presence of few studies. By contrast, the root-mean-square error is relatively greater. An illustrative example is provided demonstrating implementation of the presented network meta-analysis model in a clinical setting. 相似文献