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51.
Shujian Wu Zuhaib F. Bhat Rochelle S. Gounder Isam A. Mohamed Ahmed Fahad Y. Al-Juhaimi Yu Ding Alaa E. -D. A. Bekhit 《Nutrients》2022,14(3)
The effect of diet on the composition of gut microbiota and the consequent impact on disease risk have been of expanding interest. The present review focuses on current insights of changes associated with dietary protein-induced gut microbial populations and examines their potential roles in the metabolism, health, and disease of animals. Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) protocol was used, and 29 highly relevant articles were obtained, which included 6 mouse studies, 7 pig studies, 15 rat studies, and 1 in vitro study. Analysis of these studies indicated that several factors, such as protein source, protein content, dietary composition (such as carbohydrate content), glycation of protein, processing factors, and protein oxidation, affect the digestibility and bioavailability of dietary proteins. These factors can influence protein fermentation, absorption, and functional properties in the gut and, consequently, impact the composition of gut microbiota and affect human health. While gut microbiota can release metabolites that can affect host physiology either positively or negatively, the selection of quality of protein and suitable food processing conditions are important to have a positive effect of dietary protein on gut microbiota and human health. 相似文献
52.
目的 探讨多种细胞组分、细胞因子、信号转导分子等在气管上皮基底干细胞(airway basal stem cells,ABSCs)体外增殖和分化过程中的调控作用.方法 采用细胞外基质替代物Matrigel三维体外培养体系,辅以免疫组化分析,观察了几种常见的对干细胞增殖分化发挥重要作用的因素对ABSCs体外集落形成数量、集落大小及分化潜能的影响.结果 成纤维细胞较内皮细胞能显著提高ABSCs集落增殖和分化潜能.成纤维细胞生长因子(FGFs)能增加ABSCs体外集落形成数量与直径,并诱导其向分泌性细胞分化.同时给予FGFs及其受体阻滞剂处理,FGFs诱导的集落增殖效应消失.LIF、ALK5-I或ROCK-I处理后,ABSCs形成的集落数量和直径也显著增加,并诱导其向纤毛上皮细胞或分泌性细胞分化.结论 小鼠ABSCs不依赖成纤维细胞,但共培养能增强其增殖和分化能力;内皮细胞对ABSCs增殖和分化能力促进作用有限;FGFs促进ABSCs的增殖和分化,其效应能被其受体阻滞剂消除;LIF、ALK5-I或ROCK-I亦促进ABSCs的增殖和分化.研究结果将为小鼠ABSCs的生物学特性及其影响因素的深入研究奠定基础,为未来ABSCs修复性治疗相关疾病和损伤提供了实验学依据. 相似文献
53.
Kevin M. Smith W. Stephen McNeil Alaa S. Abd‐El‐Aziz 《Macromolecular chemistry and physics.》2010,211(1):10-16
Organometallic‐mediated radical polymerization (OMRP) has emerged as a powerful new class of living controlled radical polymerization. In order to fulfill its potential in the polymerization of vinyl acetate (VOAc) and other challenging monomers, the effects of ancillary ligands on the metal‐alkyl bond dissociation energy in OMRP reagents must be thoroughly explored. Recent results investigating structure‐activity relationships in well‐defined cobalt, iron and chromium complexes will be discussed. The involvement of radical intermediates in oxidative addition of secondary alkyls for catalytic cross‐coupling reactions catalyzed by first row transition metals will also be examined for relevant design concepts.
54.
Abdulrazak Alghareeb Alaa Sabry Hassan Bawadekji Khalid Alsaran 《Therapeutic apheresis and dialysis : official peer-reviewed journal of the International Society for Apheresis, the Japanese Society for Apheresis, the Japanese Society for Dialysis Therapy》2013,17(1):30-34
Secondary hyperparathyroidism remains a serious problem in hemodialysis patients. The use of vitamin D analogs still constitutes a basis for its treatment. This study was carried out to evaluate the efficacy of intravenous administration of alfacalcidol once versus twice or thrice weekly in hemodialysis patients with secondary hyperparathyroidism. Twenty‐nine end‐stage renal disease patients maintained on hemodialysis for more than one year were included in this prospective study after signing the consent. These patients with secondary hyperparathyroidism had been on intravenous alfacalcidol twice or thrice per week and were followed up to 4 months (stage 1). Then they were shifted to intravenous alfacalcidol once weekly starting with the last total weekly intravenous dose for another 4 months (stage 2). The dose of alfacalcidol was adjusted according to intact parathyroid hormone, serum calcium and phosphorus levels, and calcium‐phosphorus product. Intact parathyroid hormone, calcium, phosphorus, calcium‐phosphorus product were measured monthly. Parathyroid ultrasound was done as a baseline and then repeated at the end of stage 1 and stage 2. The intact parathyroid hormone was reduced from 49.72 ± 2.72 pmol/L (mean ± standard error of the mean [SEM] during stage 1 to 42.13 ± 2.15 pmol/L during stage 2 (P = 0.005). Dose of alfacalcidol was reduced from 18.80 ± 1.15 µg/month (mean ± SEM) in stage 1 to 15.18 ± 1.27 µg/month in stage 2 (P = 0.008), and consequently the cost of alfacalcidol was reduced from 21.05 ± 1.25 US$/month (mean ± SEM) during stage 1 to 16.87 ± 1.40 US$/month during stage 2 (P = 0.008). Although the phosphorus level increased from 1.56 ± 0.36 mmol/L (mean ± SD) in stage 1 to 1.70 ± 0.46 mmol/ L in stage 2 (P = 0.003), and calcium‐phosphorus product increased from 3.48 ± 0.82 mmol2/L2 (mean ± SD) in stage 1 to 3.76 ± 1.00 mmol2/L2 in stage 2 (P = 0.017), they remained in the target levels recommended by the Kidney Disease Outcomes Quality Initiative guidelines. No serious effects were observed during stage 1 and stage 2, respectively. Intravenous alfacalcidol once weekly is effective, safe and less costly in suppressing intact parathyroid hormone compared to twice or thrice weekly administration in chronic hemodialysis patients. 相似文献
55.
56.
With the projected increase in the production of heavy oil due to the energy crisis, asphaltene-related issues are likely to come to the forefront. This leads to operational problems, safety hazards, and oil production deficiencies, resulting in huge economic losses for the petroleum industry. Therefore, in this work, we aimed to inhibit asphaltene precipitation using ionic liquid (IL) compounds. ILs with long alkyl chains can inhibit the precipitation of asphaltene molecules due to the π–π* interactions between them and the formation of hydrogen bonds. A series of imidazolium-based ionic liquids, IL-0, IL-4, IL-10, and IL-16, were synthesized with yield percents of 79, 81, 80, and 83%, respectively. The prepared materials were characterized well using FTIR, 1H-NMR, and Elemental Analysis. The surface tension, interfacial tension (IFT), and different surface parameters were investigated at different temperatures to simulate the reservoir temperature. IL-0, IL-4, IL-10, and IL-16 displayed their γcmc values at 35, 34, 31, and 32 mN/m at 303 °K, respectively. It was found that the prepared ILs are good surfactants with low values of interfacial tension. Quantum structure–activity relationships using Density Functional Theory (DFT) were used to investigate the geometry optimization electronic structures, the energy gap (ΔE), and the reactivity of the cations of the prepared ILs. The synthesized ILs were evaluated as asphaltene dispersants using two different techniques. The viscometric technique showed that the asphaltene onset precipitation was 28.5 vol.%. This percent was postponed to 42.8, 50, 78.5, and 64.3 vol.%, after adding IL-0, IL-4, IL-10, and IL-16, respectively, and the spectroscopic technique confirmed the results. 相似文献
57.
Anter Mohamed Elsibai Shabbana Ayman Abd Elkader Elhalaby Alaa Eldin Fatahlla Youssif Hager Abd Elshafy Abd Elfattah Elkhouly Nabih Ibrahim 《生殖与发育医学(英文)》2021,(3):150-155
Objective::To investigate the effect of early versus late amniotomy after induction of labor (IOL) with vaginally administered misoprostol.Methods::This randomi... 相似文献
58.
59.
El-Ghoneimi A Deffarges C Hankard R Jean-Eudes F Aigrain Y Jacqz-Aigrain E 《The Journal of urology》2002,168(2):694-697
PURPOSE: Intravesical morphine was recently recommended to reduce postoperative pain after reimplantation surgery for vesicoureteral reflux in children. The efficacy of such treatment, so far solely evaluated by open study, needed to be confirmed. MATERIALS AND METHODS: After parental informed consent was obtained, 80 children requiring Cohen cross-trigonal reimplantation were considered for inclusion in a double-blind study. On the day of surgery patients were randomly assigned to receive either 0.04 mg./kg. morphine per hour or placebo (normal saline) at a constant intravesical infusion rate of 0.08 ml./kg. per hour. Postoperative pain was assessed every 3 hours using a pain score adapted to patient age. If the score was above a predefined limit, patients received intravenous acetaminophen and nalbuphine alternately every 3 hours. Bladder infusion was discontinued after 48 hours. RESULTS: Mean and maximum pain scores as well as the number of scores above the limit were not statistically different when comparing the morphine and placebo groups. There was no difference in the number of doses of analgesics administered. Urine output, voiding frequency and the number of painful voiding episodes were not significantly different between the 2 groups. Plasma morphine concentrations were 3.0 +/- 2.7 and 1.9 +/- 1.9 ng./ml. at 24 and 48 hours in the morphine group and undetectable in the placebo group. CONCLUSIONS: Intravesical administration of morphine is not effective for relieving postoperative pain during the first 48 hours after intravesical ureteral reimplantation. This study emphasizes the importance of controlled studies in evaluating the effectiveness of a new drug or procedure before recommending its use for all patients. 相似文献
60.
Although unusual, pregnancy in chronic dialysis patients does occur. In fact, the percent of successful pregnancies in women on chronic dialysis may be increasing. But unfortunately, the rates for premature delivery, neonatal death, maternal hypertension, and preeclampsia in chronic pregnant dialysis patients are high. Only 50% of pregnancies result in a surviving infant and over 80% of live born infants are premature, often severely premature. The key to improving the outcome of pregnancy in dialysis patients lies in decreasing premature labor and premature rupture of membranes in the late second and early third trimester. In this article, the incidence, duration, fetal and maternal complications, and outcomes of pregnancy in women on chronic dialysis are reviewed. The management of anemia, hypertension, electrolytes, bone minerals, and acid–base parameters in this group of patients is also summarized. We review the prevalence of pregnancy and the fetal outcome in patients with end stage renal disease (ESRD) maintained on hemodialysis previously reported in the literature. Then we report two cases of chronic renal failure patients who conceived while they were on maintenance hemodialysis with successful fetal outcome. In addition to reassessing the previously reported reviews and case reports published in the literature, we propose management guidelines for this group of patients. We emphasize that the intensive interdisciplinary cooperation of nephrologists and obstetricians is imperative for the successful management of pregnancy under these conditions. We advise that all aspects of dialysis, including duration, adequacy, nutrition, anemia, calcium and phosphate metabolism and BP control need to be closely followed throughout the course of pregnancy. 相似文献