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21.
A strain of long-chain alkane–degrading bacteria, BT1A, was isolated from oil-contaminated soil in Diyarbak?r, in the southeast of Turkey. Morphological, biochemical, and physiological characterization and 16S rRNA gene sequence analysis showed that the strain BT1A was a member of Acinetobacter genus, and it was found to be closely related to Acinetobacter baumannii. The strain BT1A was able to utilize crude petroleum as carbon and energy sources in order to grow. Among the aliphatic hydrocarbons, growth was observed only in the medium containing long-chain alkanes (tridecane, pentadecane, and hexadecane) and squalene. Hexadecane was the most preferred hydrocarbon among the long-chain alkanes. Gas chromatography–mass spectrometry (GC-MS) analysis showed that BT1A degraded 83% of n-alkanes of 1% crude oil in 7 days. The present study indicates that the isolated strain can well be used for biodegradation of hydrocarbons in oil-contaminated sites.  相似文献   
22.
Tryptophan catabolism is highly conserved and generates important bioactive metabolites, including kynurenines, and in some animals, NAD+. Aging and inflammation are associated with increased levels of kynurenine pathway (KP) metabolites and depleted NAD+, factors which are implicated as contributors to frailty and morbidity. Contrastingly, KP suppression and NAD+ supplementation are associated with increased life span in some animals. Here, we used DGRP_229 Drosophila to elucidate the effects of KP elevation, KP suppression, and NAD+ supplementation on physical performance and survivorship. Flies were chronically fed kynurenines, KP inhibitors, NAD+ precursors, or a combination of KP inhibitors with NAD+ precursors. Flies with elevated kynurenines had reduced climbing speed, endurance, and life span. Treatment with a combination of KP inhibitors and NAD+ precursors preserved physical function and synergistically increased maximum life span. We conclude that KP flux can regulate health span and life span in Drosophila and that targeting KP and NAD+ metabolism can synergistically increase life span.  相似文献   
23.
In engineered bone grafts, the combined actions of bone-forming cells, matrix and bioactive stimuli determine the eventual performance of the implant. The current notion is that well-built 3D constructs include the biological elements that recapitulate native bone tissue structure to achieve bone formation once implanted. The relatively new technology of organ/tissue printing now enables the accurate 3D organization of the components that are important for bone formation and also addresses issues, such as graft porosity and vascularization. Bone printing is seen as a great promise, because it combines rapid prototyping technology to produce a scaffold of the desired shape and internal structure with incorporation of multiple living cell types that can form the bone tissue once implanted.  相似文献   
24.
Leaf area is one of the most important parameter for plant growth. Reliable equations were offered to predict leaf area for Zea mays L. cultivars. All equations produced for leaf area were derived as affected by leaf length and leaf width. As a result of ANOVA and multiregression analysis, it was found that there was a close relationship between actual and predicted growth parameters. The produced leaf-area prediction model in the present study is LA = a + b L + c W + d LZ where LA is leaf area, L is leaf length, W is maximum leaf width, LZ is leaf zone and a, b, c, d are coefficients. R 2 values were between 0.88–0.97 and standard errors were found to be significant at the p<0.001 significance level.  相似文献   
25.
Two thermophilic spore-forming strains, with optimum growth temperature at 70 °C, were isolated from compost of the “Experimental System of Composting” (Teora, Avellino, Italy). A phylogenetic analysis based on 16S rRNA gene sequences showed that these organisms represented a new species of the genus Geobacillus. Based on polyphasic taxonomic data the strains represented a novel species for which the name Geobacillus galactosidasius sp. nov. is proposed. The type strain is CF1BT (= ATCC BAA-1450T = DSM 18751T).  相似文献   
26.
Abstract It is already known that maternal overweight, obesity, and morbid obesity are associated with adverse obstetric and neonatal outcomes. To assess the prevalence of overweight and obesity, and the impact of body mass index (BMI) on maternal and neonatal outcomes in Turkey. The study population consisted of 698 singleton pregnancies whose height and weight follow up were performed from the first trimester of pregnancy and whose deliveries were monitored in Trabzon, Turkey in July 2014–June 2015. The data obtained during the study were evaluated using SPSS 21 package program. The differences in variables were assessed by Chi-square-test for categorical data or by One-way Anova test for continuous data. The results were evaluated at a confidence interval of 95% and at a significance level of p?<?0.05. According to the BMI of the women in the study, 68.8% were in normal weight, 20.6% were overweight, 3.9% were obese, and the majority was in the 20–29 age group and 8–15.9?kg. The rate of cesarean, instrumental delivery, induction, episiotomy, late breastfeeding, low apgar (<7 at 5?min), neonatal intensive care unit admission requirement, the newborn at 4000?g or more in overweight (BMI 25–29.9) and obese (BMI?≥?30) pregnancies was higher and the first and second phases of labor were longer (p?<?0.05). The study showed that as the pre-pregnancy body mass index and gestational weight gain increased the rates of cesarean section and interventional delivery increased and the neonatal need for neonatal intensive care unit increased.  相似文献   
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A response surface method of smoothing fermentation data with spline functions is presented. The available electron balance is used to optimally select the values of the smoothing parameters associated with the spline functions. The method is applied to six sets of anaerobic fermentation data in which pure and mixed cultures are grown in batch followed by fed batch culture. Lactobacillus bulgaricus and Streptococcus thermophilus are cultured on 3% dry milk. Measured concentrations of biomass, lactose, galactose, lactic acid, and other acid products are smoothed using spline functions. Values of specific growth rate, specific lactose consumption rate, specific galactose formation rate, and specific acid product formation rate are estimated and the consistency of the results is examined using the available electron balance. The results show that the method works reasonably well, but that an upper bound should be used for the smoothing parameters to obtain accurate estimates of the derivative quantities.  相似文献   
30.
Different biochemical pathways and cellular mechanisms play role in the pathogenesis of pulmonary hypertension (PH) in chronic obstructive pulmonary disease (COPD). Alveolar hypoxia is not the only determinant of vascular remodeling, genetic factors are thought to have additive effects. We aimed to investigate the effects of endothelial nitric oxide synthase (eNOS A/B), angiotensin converting enzyme (ACE I/D) and serotonin transporter (5-HTT L/S) gene polymorphisms on development and severity of PH in COPD patients. 50 COPD patients without PH (group 1); 30 COPD patients with PH confirmed with echocardiography (group 2) and 49 healthy subjects (group 3) as control group were included to the study. eNOS A/B, ACE I/D and 5-HTT L/S gene polymorphisms and allele frequencies of COPD patients with and without PH and healthy subjects were determined. Functional parameters and echocardiographic measurements were recorded. Patients with PH were also assessed in two subgroups according to the severity of pulmonary arterial pressure (PAP). Significant differences among three groups in the distribution of 5-HTT genotype and allele frequency were present (respectively p = 0.002; p = 0.021). In group 2, LL and LS genotype rate was 93.3 % with a frequency of 71.2 % L allele and 28.3 % of S allele. 5-HTT LL genotype was present in 88.9 % of patients with PAP ≥50 mmHg significantly (p = 0.012). Other genotype distributions were not significantly different between two subgroups. The results of this study can suggest that COPD patients with L allele of 5-HTT may have higher risk for the development of PH and patients with LL genotype of 5-HTT may present higher PAP. We also demonstrated that eNOS and ACE gene polymorphisms were not associated with the development and severity of PH in our study population. Further studies with larger numbers of patients are needed to explore these relationships.  相似文献   
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