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871.
Mohammad Javad Najafpanah Mostafa Sadeghi Abolfazl ZaliHossein Moradi-shahrebabak Hojatollah Mousapour 《Gene》2014
Acetyl CoA Carboxylase 1 (ACC1) is a biotin-dependent enzyme that catalyzes the carboxylation of Acetyl CoA to form Malonyl CoA, the key intermediate metabolite in fatty acid synthesis. In this study, the mRNA expression of the ACC1 gene was evaluated in four different tissues (liver, visceral fat, subcutaneous fat, and longissimus muscle) of the domestic goat (Capra hircus) kids feeding on four different levels of trivalent chromium (0, 0.5, 1, and 1.5 mg/day) as food supplementation. RT-qPCR technique was used for expression analyses and heat shock protein 90 gene (HSP-90) was considered as reference gene for data normalization. Our results revealed that 1.5 mg/day chromium significantly reduced the expression of the ACC1 gene in liver, visceral fat, and subcutaneous fat tissues, but not in longissimus muscles (P < 0.05). We measured some phenotypic traits of kid's carcasses to detect their probable correlations with chromium-mediated downregulation of ACC1 expression. Interestingly, changes in ACC1 expression were accompanied with decreased accumulation of fats in adipose tissues such that the subcutaneous fat thickness and heart fat percentage decreased in kids feeding on chromium. By contrast, chromium supplemented kids showed higher percentage of muscles despite the fact that their total body weight did not differ from that of non-supplemented kids. Our study suggests that trivalent chromium alters the direction of energy accumulation towards muscles rather than fats and provides insights into application of chromium supplementation as a useful strategy for improvement of meat quality in domestic animals. 相似文献
872.
HPLC‐Fluorescence Method for the Enantioselective Analysis of Propranolol in Rat Serum Using Immobilized Polysaccharide‐Based Chiral Stationary Phase
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Amer M. Alanazi Mohamed M. Hefnawy Abdulrahman A. AL‐Majed Aymen K. AL‐ Suwailem Mohamed G. Kassem Gamal A. Mostafa Sabry M. Attia Mohammed M. Khedr 《Chirality》2014,26(4):194-199
A stereoselective high‐performance liquid chromatographic (HPLC) method was developed and validated to determine S‐(?)‐ and R‐(+)‐propranolol in rat serum. Enantiomeric resolution was achieved on cellulose tris(3,5‐dimethylphenylcarbamate) immobilized onto spherical porous silica chiral stationary phase (CSP) known as Chiralpak IB. A simple analytical method was validated using a mobile phase consisted of n‐hexane‐ethanol‐triethylamine (95:5:0.4%, v/v/v) at a flow rate of 0.6 mL min‐1 and fluorescence detection set at excitation/emission wavelengths 290/375 nm. The calibration curves were linear over the range of 10–400 ng mL‐1 (R = 0.999) for each enantiomer with a detection limit of 3 ng mL‐1. The proposed method was validated in compliance with ICH guidelines in terms of linearity, accuracy, precision, limits of detection and quantitation, and other aspects of analytical validation. Actual quantification could be made for propranolol isomers in serum obtained from rats that had been intraperitoneally (i.p.) administered a single dose of the drug. The proposed method established in this study is simple and sensitive enough to be adopted in the fields of clinical and forensic toxicology. Molecular modeling studies including energy minimization and docking studies were first performed to illustrate the mechanism by which the active enantiomer binds to the β‐adrenergic receptor and second to find a suitable interpretation of how both enantiomers are interacting with cellulose tris(3,5‐dimethylphenylcarbamate) CSP during the process of resolution. The latter interaction was demonstrated by calculating the binding affinities and interaction distances between propranolol enantiomers and chiral selector. Chirality 26:194–199, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
873.
Ashleigh E. Schaffer Veerle R.C. Eggens Ahmet Okay Caglayan Miriam S. Reuter Eric Scott Nicole G. Coufal Jennifer L. Silhavy Yuanchao Xue Hulya Kayserili Katsuhito Yasuno Rasim Ozgur Rosti Mostafa Abdellateef Caner Caglar Paul R. Kasher J. Leonie Cazemier Marian A. Weterman Vincent Cantagrel Na Cai Christiane Zweier Umut Altunoglu N. Bilge Satkin Fesih Aktar Beyhan Tuysuz Cengiz Yalcinkaya Huseyin Caksen Kaya Bilguvar Xiang-Dong Fu Christopher R. Trotta Stacey Gabriel André Reis Murat Gunel Frank Baas Joseph G. Gleeson 《Cell》2014
874.
Frederick A. Matsen IV Christopher T. Small Khanh Soliven Gregory A. Engel Mostafa M. Feeroz Xiaoxing Wang Karen L. Craig M. Kamrul Hasan Michael Emerman Maxine L. Linial Lisa Jones-Engel 《PLoS computational biology》2014,10(2)
Simian Foamy Virus (SFV) can be transmitted from non-human primates (NHP) to humans. However, there are no documented cases of human to human transmission, and significant differences exist between infection in NHP and human hosts. The mechanism for these between-host differences is not completely understood. In this paper we develop a new Bayesian approach to the detection of APOBEC3-mediated hypermutation, and use it to compare SFV sequences from human and NHP hosts living in close proximity in Bangladesh. We find that human APOBEC3G can induce genetic changes that may prevent SFV replication in infected humans in vivo. 相似文献
875.
Karim H. I. Abd-El-Maeboud Mohamed A. M. F. Kortam Mohamed S. Ali Mostafa I. Ibrahim Radwa M. M. Z. Mohamed 《PloS one》2014,9(8)
Objective
Preliminary evaluation of efficacy and safety of uzara use in treatment of moderate and severe primary dysmenorrhea in comparison to ibuprofen.Materials and Methods
This randomized, comparative two way cross-over study comprised 60 single female students at Faculty of Medicine, Ain Shams University, Egypt, aged 19–28 years with moderate (n = 46) or severe (n = 14) primary dysmenorrhea. Participants were randomized to take either uzara (80 mg/8 hours for two doses, then 40 mg/8 hours) then ibuprofen (400 mg/6 hours) in two subsequent cycles or vice versa. The pain intensity, using VAS, was recorded immediately before taking the medication (0 hour) and after 4, 12, 24, 48–60, 96–120 hours. Main outcome measures included effectiveness of pain relief defined as drop of VAS to 3 or less, patient''s global evaluation of the drug, absence from school, the use of a rescue medication, and, in those who continued the treatment, the pain intensity difference (PID) at different points after start of medication and its sum (SPID).Results
Uzara was comparably effective to ibuprofen (78.3% vs. 86.7% of cycles; respectively), with comparable rates of effectiveness on global evaluation (being around 50% for either drug), and rates of school absences (11.7% vs. 13.3%; respectively). The need for rescue medication was different (18.3% and 10%; respectively), albeit with no statistical significance. The means of PID at different time points and SPID were comparable, with significantly lower average mean of VAS scores compared to that felt with no medication (1.6 vs. 6.8, p<0.001). Side effects were less with uzara than ibuprofen (0% vs. 8.3%, p<0.05).Conclusions
Uzara might be as effective as ibuprofen in management of primary dysmenorrhea but with less side effects. These findings need to be confirmed by a properly designed trial with a larger sample size.Trial Registration
Current Controlled Trials ISRCTN25618258 相似文献876.
Badreldin H. Ali Suhail Al-Salam Mohammed Al Za'abi Khalid A. Al Balushi Aishwarya Ramkumar Mostafa I. Waly Javid Yasin Sirin A. Adham Abderrahim Nemmar 《PloS one》2014,9(7)
Different modes of exercise are reported to be beneficial in subjects with chronic kidney disease (CKD). Similar benefits have also been ascribed to the dietary supplement gum acacia (GA). Using several physiological, biochemical, immunological, and histopathological measurements, we assessed the effect of swimming exercise (SE) on adenine –induced CKD, and tested whether SE would influence the salutary action of GA in rats with CKD. Eight groups of rats were used, the first four of which were fed normal chow for 5 weeks, feed mixed with adenine (0.25% w/w) to induce CKD, GA in the drinking water (15% w/v), or were given adenine plus GA, as above. Another four groups were similarly treated, but were subjected to SE during the experimental period, while the first four groups remained sedentary. The pre-SE program lasted for four days (before the start of the experimental treatments), during which the rats were made to swim for 5 to 10 min, and then gradually extended to 20 min per day. Thereafter, the rats in the 5th, 6th, 7th, and 8th groups started to receive their respective treatments, and were subjected to SE three days a week for 45 min each. Adenine induced the typical signs of CKD as confirmed by histopathology, and the other measurements, and GA significantly ameliorated all these signs. SE did not affect the salutary action of GA on renal histology, but it partially improved some of the above biochemical and physiological analytes, suggesting that addition of this mode of exercise to GA supplementation may improve further the benefits of GA supplementation. 相似文献
877.
878.
Noha H Youssef Kristen N Savage-Ashlock Alexandra L McCully Brandon Luedtke Edward I Shaw Wouter D Hoff Mostafa S Elshahed 《The ISME journal》2014,8(3):636-649
We investigated the mechanisms of osmoadaptation in the order Halobacteriales, with special emphasis on Haladaptatus paucihalophilus, known for its ability to survive in low salinities. H. paucihalophilus genome contained genes for trehalose synthesis (trehalose-6-phosphate synthase/trehalose-6-phosphatase (OtsAB pathway) and trehalose glycosyl-transferring synthase pathway), as well as for glycine betaine uptake (BCCT family of secondary transporters and QAT family of ABC transporters). H. paucihalophilus cells synthesized and accumulated ∼1.97–3.72 μmol per mg protein of trehalose in a defined medium, with its levels decreasing with increasing salinities. When exogenously supplied, glycine betaine accumulated intracellularly with its levels increasing at higher salinities. RT-PCR analysis strongly suggested that H. paucihalophilus utilizes the OtsAB pathway for trehalose synthesis. Out of 83 Halobacteriales genomes publicly available, genes encoding the OtsAB pathway and glycine betaine BCCT family transporters were identified in 38 and 60 genomes, respectively. Trehalose (or its sulfonated derivative) production and glycine betaine uptake, or lack thereof, were experimentally verified in 17 different Halobacteriales species. Phylogenetic analysis suggested that trehalose synthesis is an ancestral trait within the Halobacteriales, with its absence in specific lineages reflecting the occurrence of gene loss events during Halobacteriales evolution. Analysis of multiple culture-independent survey data sets demonstrated the preference of trehalose-producing genera to saline and low salinity habitats, and the dominance of genera lacking trehalose production capabilities in permanently hypersaline habitats. This study demonstrates that, contrary to current assumptions, compatible solutes production and uptake represent a common mechanism of osmoadaptation within the Halobacteriales. 相似文献
879.
Mostafa?Sefidgar M?SoltaniEmail author Kaamran?Raahemifar Hossein?Bazmara Seyed?Mojtaba?Mousavi?Nayinian Majid?Bazargan 《Journal of biological engineering》2014,8(1):12
Background
The computational methods provide condition for investigation related to the process of drug delivery, such as convection and diffusion of drug in extracellular matrices, drug extravasation from microvessels or to lymphatic vessels. The information of this process clarifies the mechanisms of drug delivery from the injection site to absorption by a solid tumor. In this study, an advanced numerical method is used to solve fluid flow and solute transport equations simultaneously to investigate the effect of tumor shape and size on drug delivery to solid tumor.Methods
The advanced mathematical model used in our previous work is further developed by adding solute transport equation to the governing equations. After applying appropriate boundary and initial conditions on tumor and surrounding tissue geometry, the element-based finite volume method is used for solving governing equations of drug delivery in solid tumor. Also, the effects of size and shape of tumor and some of tissue transport parameters such as effective pressure and hydraulic conductivity on interstitial fluid flow and drug delivery are investigated.Results
Sensitivity analysis shows that drug delivery in prolate shape is significantly better than other tumor shapes. Considering size effect, increasing tumor size decreases drug concentration in interstitial fluid. This study shows that dependency of drug concentration in interstitial fluid to osmotic and intravascular pressure is negligible.Conclusions
This study shows that among diffusion and convection mechanisms of drug transport, diffusion is dominant in most different tumor shapes and sizes. In tumors in which the convection has considerable effect, the drug concentration is larger than that of other tumors at the same time post injection.880.
Salma Ahmed Shawky Osama Gaber Ezzat Mostafa Walaa Mohamed Sarhan 《Reports of Biochemistry & Molecular Biology》2021,10(1):119
Background:Obesity is a multifactorial metabolic disease resulting from behavioral and genetic factors. Obesity is linked to diabetes mellitus and hypertension, which are considered as major risk factors for chronic kidney disease (CKD); moreover, it has a direct effect on developing CKD and end stage renal disease (ESRD). Here was aimed to examine the association between uncoupling protein 2 (UCP2) gene expression and obesity in CKD patients. Methods:UCP2 gene expression was analyzed by real time polymerase chain reaction (RT-PCR) in 93 participants divided into three groups. The groups included 31 non-obese CKD patients, 31 obese CKD patients, and 31 healthy, age-matched, unrelated volunteers as a control group. Results:UCP2 gene expression was significantly relevant when comparing the non-obese CKD and obese CKD groups to the control group (p< 0.001). No significant association was found when the groups were compared by gender; Chi-square (X2) was 2.38 and p= 0.304. A significant negative correlation was found between UCP2 gene expression and BMI in CKD (p< 0.05).Conclusion:These results indicate that UCP2 gene expression plays a significant role as a risk factor for obesity in CKD patients. Key Words: Chronic Kidney Disease (CKD), Obesity, Uncoupling Protein 2 (UCP2) Gene Expression, Real-Time Polymerase Chain Reaction (RT-PCR) 相似文献