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661.
Background
The literature is nearly unanimous in recommending elective cesarean delivery at 39 weeks of gestation because of the lower rates of neonatal respiratory complications compared to 38 weeks. However, elective cesarean delivery at 39 weeks or more may have maternal and other fetal consequences compared to delivery at 38 weeks, which are not always addressed in these studies. 相似文献662.
Fuhang Song Na Yang Zeinab G. Khalil Angela A. Salim Jiahui Han Paul V. Bernhardt Rui Lin Xiuli Xu Robert J. Capon 《化学与生物多样性》2021,18(11):e2100674
Chemical investigation on a Streptomyces sp. strain MS180069 isolated from a sediment sample collected from the South China Sea, yielded the new benzo[f]isoindole-dione alkaloid, bhimamycin J ( 1 ). The structure was determined by extensive spectroscopic analysis, including HRMS, 1D, 2D NMR, and X-ray diffraction techniques. A molecular docking study revealed 1 as a new molecular motif that binds with human angiotensin converting enzyme2 (ACE2), recently described as the cell surface receptor responsible for uptake of 2019-CoV-2. Using enzyme assays we confirm that 1 inhibits human ACE2 79.7 % at 25 μg/mL. 相似文献
663.
Althaf Hussain Shaik Shajidha Ruksar Shaik Abdul Saheer Shaik Ali Daoud Manoharadas Salim Lakshmi Devi Kodidhela 《Saudi Journal of Biological Sciences》2021,28(4):2575-2580
ObjectiveThis research designed to analyze the in vivo and in silico ameliorative action of maslinic acid (MA) and gallic acid (GA) on reactive oxygen species generating enzyme xanthine oxidase (XO) in isoprenaline or isoproterenol (ISO) induced myocardial infarcted rats.MethodsAlbino Wistar rats were categorized into four groups with eight rats in each group. A dose of 15 mg/kg of MA and GA were pretreated to each MA and GA groups for seven days. A dose of 85 mg/kg of ISO administered to the ISO group along with MA and GA groups except normal group on two consecutive days of pretreatment. All animals sacrificed and the heart tissues were collected for the analysis of XO. The in silico molecular docking analysis of the compounds MA and GA with XO was analyzed by using Gold 3.0.1 software.ResultsXO enzyme levels were significantly increased in the heart homogenate of ISO administered rats when compared to normal rats. Pretreatment of MA and GA to ISO treated rats significantly brought XO enzyme to the near normal levels which indicate the protective action of MA and GA against myocardial necrosis. The in vivo results were further supported by the in silico molecular docking study which revealed the inhibition of XO enzyme by the formation of enzyme and ligand complex with the compounds MA and GA.ConclusionMA and GA compounds manifested the ameliorative effect against ISO administrated myocardial necrosis by inhibiting the free radical generating enzyme XO which is evidenced by both in vivo and in silico studies. 相似文献
664.
Violeta Díaz-Sánchez Alejandro F. Estrada M. Carmen Limón Salim Al-Babili Javier Avalos 《Eukaryotic cell》2013,12(9):1305-1314
The genome of the ascomycete Neurospora crassa encodes CAO-1 and CAO-2, two members of the carotenoid cleavage oxygenase family that target double bonds in different substrates. Previous studies demonstrated the role of CAO-2 in cleaving the C40 carotene torulene, a key step in the synthesis of the C35 apocarotenoid pigment neurosporaxanthin. In this work, we investigated the activity of CAO-1, assuming that it may provide retinal, the chromophore of the NOP-1 rhodopsin, by cleaving β-carotene. For this purpose, we tested CAO-1 activity with carotenoid substrates that were, however, not converted. In contrast and consistent with its sequence similarity to family members that act on stilbenes, CAO-1 cleaved the interphenyl Cα-Cβ double bond of resveratrol and its derivative piceatannol. CAO-1 did not convert five other similar stilbenes, indicating a requirement for a minimal number of unmodified hydroxyl groups in the stilbene background. Confirming its biological function in converting stilbenes, adding resveratrol led to a pronounced increase in cao-1 mRNA levels, while light, a key regulator of carotenoid metabolism, did not alter them. Targeted Δcao-1 mutants were not impaired by the presence of resveratrol, a phytoalexin active against different fungi, which did not significantly affect the growth and development of wild-type Neurospora. However, under partial sorbose toxicity, the Δcao-1 colonies exhibited faster radial growth than control strains in the presence of resveratrol, suggesting a moderate toxic effect of resveratrol cleavage products. 相似文献
665.
Ibtisam Salim Eleonora Staines-Urias Sam Mathewlynn Lior Drukker Manu Vatish Lawrence Impey 《PLoS medicine》2021,18(1)
BackgroundBreech presentation at term contributes significantly to cesarean section (CS) rates worldwide. External cephalic version (ECV) is a safe procedure that reduces term breech presentation and associated CS. A principal barrier to ECV is failure to diagnose breech presentation. Failure to diagnose breech presentation also leads to emergency CS or unplanned vaginal breech birth. Recent evidence suggests that undiagnosed breech might be eliminated using a third trimester scan. Our aim was to evaluate the impact of introducing a routine 36-week scan on the incidence of breech presentation and of undiagnosed breech presentation.Methods and findingsWe carried out a population-based cohort study of pregnant women in a single unit covering Oxfordshire, United Kingdom. All women delivering between 37+0 and 42+6 weeks gestational age, with a singleton, nonanomalous fetus over a 4-year period (01 October 2014 to 30 September 2018) were included. The mean maternal age was 31 years, mean BMI 26, 44% were nulliparous, and 21% were of non-white ethnicity. Comparisons between the 2 years before and after introduction of routine 36-week scan were made for 2 primary outcomes of (1) the incidence of breech presentation and (2) undiagnosed breech presentation. Secondary outcomes related to ECV, mode of birth, and perinatal outcomes. Relative risks (RRs) with 95% confidence intervals (CIs) are reported. A total of 27,825 pregnancies were analysed (14,444 before and 13,381 after). A scan after 35+0 weeks was performed in 5,578 (38.6%) before, and 13,251 (99.0%) after (p < 0.001). The incidence of breech presentation at birth did not change significantly (2.6% and 2.7%) (RR 1.02; 95% CI 0.89, 1.18; p = 0.76). The rate of undiagnosed breech before labour reduced, from 22.3% to 4.7% (RR 0.21; 95% CI 0.12, 0.36; p < 0.001). Vaginal breech birth rates fell from 10.3% to 5.3% (RR 0.51; 95% CI 0.30, 0.87; p = 0.01); nonsignificant increases in elective CS rates and decreases in emergency CS rates for breech babies were seen. Neonatal outcomes were not significantly altered. Study limitations include insufficient numbers to detect serious adverse outcomes, that we cannot exclude secular changes over time which may have influenced our results, and that these findings are most applicable where a comprehensive ECV service exists.ConclusionsIn this study, a universal 36-week scan policy was associated with a reduction in the incidence but not elimination of undiagnosed term breech presentation. There was no reduction in the incidence of breech presentation at birth, despite a comprehensive ECV service.Ibtisam Salim and co-workers report on incidence of breech presentation in pregnant women receiving a 36-week scan. 相似文献
666.
667.
Ibrahim M. Gosadi Khaled A. Daghriri Abdullah A. Otayf Abdulrhman A. Nemri Abdulaziz A. Kaal Abdullah M. Qussadi Manal M. Maashi Alshaymaa M. Arishy Hadeel M. Mushafa Abdulrhman M. Salim 《Saudi Journal of Biological Sciences》2021,28(5):2951-2955
BackgroundPatient’s awareness of their clinical and laboratory parameters is an indicator of the degree of involvement in achieving their management goals. This investigation aimed to identify awareness of patients affected by chronic non-communicable diseases of their clinical and laboratory parameters and factors associated with the awareness.MethodsThis study was a cross-sectional investigation conducted in the Jazan region, between January and August 2020. Data was collected during phone interviews utilizing a semi-structured questionnaire. Odds ratios (ORs) were calculated to estimate the likelihood of awareness of each clinical and laboratory parameter according to the measured demographic variables.ResultsThe total number of recruited patients was 675. The mean age of participants was 53.7 years and the 28.7% of patients were illiterate. About 17% of the patient do not attend follow-up visits to any healthcare provider. When patients were asked about their parameters, 87% of them were able to report their body weight and 74% were able to report their height. However, less than half of patients were aware of their glycated hemoglobin level (HbA1c) (271/675 patients) and systolic blood pressure (BP) level (329/ 675 patients), and a minority were aware of their total cholesterol level (71/675 patients). Being female, resident in a rural area, illiterate, and older than 53 was strongly associated with high odds of limited awareness about their own clinical and laboratory parameters (P values < 0.05).ConclusionAwareness of patients affected by chronic non-communicable diseases of their own clinical and laboratory parameters in the Jazan region is sub-optimal where this limited awareness is likely to be associated with the lower engagement of patients with achieving their desired management targets. 相似文献
668.
Mustafa Al-Saiedy Ryan Pratt Patrick Lai Evan Kerek Heidi Joyce Elmar Prenner Francis Green Chang-Chun Ling Ruud Veldhuizen Salim Ghandorah Matthias Amrein 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(4):1040-1049
Pulmonary surfactant forms a cohesive film at the alveolar air-lung interface, lowering surface tension, and thus reducing the work of breathing and preventing atelectasis. Surfactant function becomes impaired during inflammation due to degradation of the surfactant lipids and proteins by free radicals. In this study, we examine the role of reactive nitrogen (RNS) and oxygen (ROS) species on surfactant function with and without physiological cholesterol levels (5–10%). Surface activity was assessed in vitro in a captive bubble surfactometer (CBS). Surfactant chemistry, monolayer fluidity and thermodynamic behavior were also recorded before and after oxidation. We report that physiologic amounts of cholesterol combined with oxidation results in severe impairment of surfactant function. We also show that surfactant polyunsaturated phospholipids are the most susceptible to oxidative alteration. Membrane thermodynamic experiments showed significant surfactant film stiffening after free radical exposure in the presence of cholesterol. These results point to a previously unappreciated role for cholesterol in amplifying defects in surface activity caused by oxidation of pulmonary surfactant, a finding that may have implications for treating several lung diseases. 相似文献
669.
670.