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161.
162.
Mohammed AlSheef Mastourah Alotaibi Abdul Rehman Z. Zaidi Areej Alshamrani Aroub Alhamidi Syed Ziauddin A. Zaidi Noor Alanazi Sarah Alhathlool Ohoud Alarfaj Mohammed AlHazzaa Ghaydaa Kullab Amany Alboghdadly Amani Abu-Shaheen 《Saudi medical journal》2020,41(10):1063
Objectives:To identify the epidemiologic profile of cerebral vein thrombosis (CVT) among fasting women using oral contraceptive pills (OCPs) during the holy month of Ramadan.Methods:This retrospective study was conducted on all patients diagnosed with CVT and using OCPs from records at a tertiary care hospital in Riyadh, Saudi Arabia during 2016-2017. The study participants were categorized into 2 groups (an intermittently fasting group during the holy month of Ramadan and a non-fasting group).Results:Out of 108 female patients with CVT, 36.1% were secondary to OCP, of whom 41% participants were fasting. The most affected site was the transverse sinus. Holocephalic headache was more common amongst fasting group (68.8%) compared to non-fasting group (30.4%) (p=0.025). Dehydration (p=0.003) amongst the fasting group and protein S deficiency (p=0.027) in the non-fasting group were identified as the 2 prominent risk factors. Unfractionated heparin was the most common anticoagulant therapies used during the initiation phase for non-fasting (36.4%) and fasting groups (50%).Conclusion:All women who are using OCP should undergo formal written risk assessments for factors of CVT. Our study suggests that the negative effects of OCPs use might outweigh its benefits; thus, it should be prescribed with caution, more so in fasting patients. 相似文献
163.
Omar A. Hussein Khairul Habib R. Saidur Ali S. Muhsan Syed Shahabuddin Omer A. Alawi 《RSC advances》2019,9(66):38576
Covalent functionalization (CF-GNPs) and non-covalent functionalization (NCF-GNPs) approaches were applied to prepare graphene nanoplatelets (GNPs). The impact of using four surfactants (SDS, CTAB, Tween-80, and Triton X-100) was studied with four test times (15, 30, 60, and 90 min) and four weight concentrations. The stable thermal conductivity and viscosity were measured as a function of temperature. Fourier transform infrared spectroscopy (FTIR), thermo-gravimetric analysis (TGA), X-ray diffraction (XRD) and Raman spectroscopy verified the fundamental efficient and stable CF. Several techniques, such as dispersion of particle size, FESEM, FETEM, EDX, zeta potential, and UV-vis spectrophotometry, were employed to characterize both the dispersion stability and morphology of functionalized materials. At ultrasonic test time, the highest stability of nanofluids was achieved at 60 min. As a result, the thermal conductivity displayed by CF-GNPs was higher than NCF-GNPs and distilled water. In conclusion, the improvement in thermal conductivity and stability displayed by CF-GNPs was higher than those of NCF-GNPs, while the lowest viscosity was 8% higher than distilled water, and the best thermal conductivity improvement was recorded at 29.2%.Covalent functionalization (CF-GNPs) and non-covalent functionalization (NCF-GNPs) approaches were applied to prepare graphene nanoplatelets (GNPs). 相似文献
164.
Clustering of genomic breakpoints at the MLL locus in therapy‐related acute leukemia with t(4;11)(q21;q23) 下载免费PDF全文
Syed Khizer Hasan Gianluca Barba Markus Metzler Mariadomenica Divona Tiziana Ottone Laura Cicconi Brunangelo Falini Cristina Mecucci Francesco Lo‐Coco 《Genes, chromosomes & cancer》2014,53(3):248-254
Genomic characterization of translocation breakpoints is relevant to identify possible mechanisms underlying their origin. The consistent association of anthracylines (e.g., epirubicin and idarubicin) in inducing therapy‐related acute leukemias (t‐AL) with mixed lineage leukemia (MLL) gene rearrangement suggests that MLL translocations are causative events for t‐AL. Using asymmetric multiplex PCR strategy followed by direct DNA sequencing, we characterized the genomic breakpoints of the MLL and AFF1 genes in two patients who developed t‐AL with t(4;11)(q21;q23). Chemotherapeutic treatment of the primary disease in both patients included topoisomerase II (topo II) targeting agents. In one case, the MLL breakpoint was located in intron 9 at nucleotide position chr11:118354284 while the AFF1 breakpoint was in intron 3 at nucleotide position chr4:87992070. The breakpoint junction sequences revealed an insertion of two nucleotides at the MLL‐AFF1 junction. In the other patient, the MLL breakpoint was located in intron 11 at nucleotide position chr11:118359130‐32 and the AFF1 break was in intron 3 at nucleotide position chr4:87996215‐17. The MLL breakpoint found in the latter patient was identical to that of two previously reported cases, strongly suggesting the presence of a preferential site of DNA cleavage in the presence of topo II inhibitor. In addition, microhomologies at the breakpoint junctions were indicative of DNA repair by the non‐homologous end joining (NHEJ) pathway. This study further supports the evidence that MLL breakpoints in therapy‐related acute leukemia with MLL‐AFF1 are clustered in the telomeric half of the breakpoint cluster region that contains topo II recognition sites. © 2013 Wiley Periodicals, Inc. 相似文献
165.
Arshad Mehmood Muhammad Ishaq Lei Zhao Bushra Safdar Ashfaq‐ur Rehman Masooma Munir Ali Raza Muhammad Nadeem Waheed Iqbal Chengtao Wang 《Chemical biology & drug design》2019,93(4):387-418
Hyperuricemia (HUA), a disease due to an elevation of body uric acid level and responsible for various diseases such as gout, cardiovascular disorders, and renal failure, is a major ground debate for the medical science these days. Considering the risk factors linked with allopathic drugs for the treatment of this disease, the debate has now become a special issue. Previously, we critically discussed the role of dietary polyphenols in the treatment of HUA. Besides dietary food plants, many researchers figure out the tremendous effects of medicinal plants‐derived phytochemicals against HUA. Keeping in mind all these aspects, we reviewed all possible managerial studies related to HUA through medicinal plants (isolated compounds). In the current review article, we comprehensively discussed various bioactive compounds, chemical structures, and structure–activity relationship with responsible key enzyme xanthine oxidase. 相似文献
166.
Ahmed Bari Daniel Grenier Jabrane Azelmat Saeed Ali Syed Abdulrahman M. Al‐Obaid Eric C. Hosten 《Chemical biology & drug design》2019,94(4):1750-1759
In continuation with our research program on the development of novel bioactive molecules, we report herein the design and synthesis of a series of diversified heterocycles ( 4 – 22 ). The synthesized compounds were evaluated for their anti‐inflammatory activity. The chemical structures of the newly synthesized compounds have been confirmed by NMR, FTIR, and microanalysis. 相似文献
167.
Development of homogenous metal matrix nanocomposites with uniform distribution of nanoreinforcement, preserved matrix nanostructure features, and improved properties, was possible by means of innovative processing techniques. In this work, Al-SiC nanocomposites were synthesized by mechanical milling and consolidated through spark plasma sintering. Field Emission Scanning Electron Microscope (FE-SEM) with Energy Dispersive X-ray Spectroscopy (EDS) facility was used for the characterization of the extent of SiC particles’ distribution in the mechanically milled powders and spark plasma sintered samples. The change of the matrix crystallite size and lattice strain during milling and sintering was followed through X-ray diffraction (XRD). The density and hardness of the developed materials were evaluated as function of SiC content at fixed sintering conditions using a densimeter and a digital microhardness tester, respectively. It was found that milling for 24 h led to uniform distribution of SiC nanoreinforcement, reduced particle size and crystallite size of the aluminum matrix, and increased lattice strain. The presence and amount of SiC reinforcement enhanced the milling effect. The uniform distribution of SiC achieved by mechanical milling was maintained in sintered samples. Sintering led to the increase in the crystallite size of the aluminum matrix; however, it remained less than 100 nm in the composite containing 10 wt.% SiC. Density and hardness of sintered nanocomposites were reported and compared with those published in the literature. 相似文献
168.
169.
Dietrich E. Lorke Syed M. Nurulain Mohamed Y. Hasan Kamil Ku
a Georg A. Petroianu 《Journal of applied toxicology : JAT》2019,39(11):1506-1515
Organophosphates, useful agents as pesticides, also represent a serious danger due to their high acute toxicity. There is indication that oximes, when administered before organophosphate exposure, can protect from these toxic effects. We have tested at equitoxic dosage (25% of LD01) the prophylactic efficacy of five experimental (K‐48, K‐53, K‐74, K‐75, K‐203) and two established oximes (pralidoxime and obidoxime) to protect from mortality induced by the organophosphate paraoxon. Mortalities were quantified by Cox analysis and compared with those observed after pretreatment with a strong acetylcholinesterase inhibitor (10‐methylacridine) and after the FDA‐approved pretreatment compound pyridostigmine. All nine tested substances statistically significantly reduced paraoxon‐induced mortality. Best protection was conferred by the experimental oxime K‐48, reducing the relative risk of death (RR) to 0.10, which was statistically significantly superior to pyridostigmine (RR = 0.31). The other oximes reduced the RR to 0.13 (obidoxime), 0.20 (K‐203), 0.21 (K‐74), 0.24 (K‐75) and 0.26 (pralidoxime), which were significantly more efficacious than 10‐methylacridine (RR = 0.65). These data support the hypothesis that protective efficacy is not primarily due to cholinesterase inhibition and indicate that the tested experimental oximes may be considered promising alternatives to the established pretreatment compound pyridostigmine. 相似文献
170.