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101.
Poland syndrome is a rare congenital anomaly classically consisting of unilateral hypoplasia of the sternocostal head of the pectoralis major muscle and ipsilateral brachysyndactyly. It was first described by Alfred Poland in 1840 and may occur with different gravity. Our patient is an eight-year-old Nigerian girl with left-sided anterior chest wall defect with no detectable structural heart abnormality but presented with repeated episodes of syncopal attacks following minor trauma to the anterior chest wall. 相似文献
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Lizette Auezova Fadia Najjar Olga Selivanova Elie Hajj Moussa Mona Diab Assaf 《Journal of applied phycology》2013,25(4):1189-1196
The present study aims to investigate the levels of polyphenols and antioxidant activity in one of the most important commercial species of seaweeds in Kamchatka, an edible brown seaweed Saccharina bongardiana. Six extracts of S. bongardiana, acetone, methanol, ethanol, and the respective 70 % aqueous solutions, were assessed for total phenol content in order to determine the most efficient extracting solvent. The total phenol content was measured by the Folin–Ciocalteu method and expressed as phloroglucinol equivalents (PGE). The antioxidant tests used were 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, linoleic acid-β carotene oxidation inhibiting assay, and Fe2+ ion chelating method. Higher phenolic contents were obtained using aqueous organic solvents, as compared to the respective absolute solvents; 70 % acetone was found to be the most efficient solvent (1.039 mg PGE 100 mg?1 dry algal powder). High significant correlations were noted between total phenol content and the tested antioxidant activities; so the aqueous organic extracts exhibited the highest antioxidant activities versus DPPH radicals (EC50 values of 0.6–1.1 mg dry weight (DW) mL?1), linoleic acid-β carotene oxidation (74–78 % at 0.8 mg DW mL?1), as well as ferrous ions (EC50 values of 5.0–7.9 mg DW mL?1). Some methodological recommendations regarding the assays used and the expression of results are proposed. 相似文献
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Wafaa M. Ezzat Yasser A. Elhosary Nour A. Abdulla Hala M. Raslan Omneya M. Saleh Mona H. Ibrahim Maha A. Rasheed H. El-Hariri 《Journal of Genetic Engineering and Biotechnology》2013,11(1):69-73
BackgroundStudies revealed that insulin resistance is associated with fibrosis progression and has negative impact on sustained virological response after standard antiviral therapy in patients with chronic hepatitis C (CHC).AimTo assess the role of IR on progression of liver fibrosis and early virological response (EVR) rates in patients with chronic hepatitis C infection.Patients and methodsThe study population comprised 79 subjects who underwent combination therapy for CHC. Laboratory investigations in the form of glucose, insulin, bilirubin, alanine aminotransferase (ALT), cholesterol and triglycerides and liver biopsy were done for all patients. Insulin resistance was calculated using the homeostasis model of IR (HOMA-IR).ResultsIR was increased (>2 IU) in 31 (40.7%) of patients. Early virological response was achieved among 37 patients (48.7%). No difference in EVR, viral load or grade of liver fibrosis between patients with and without IR. A significant positive correlation was found between IR and liver steatosis.ConclusionInsulin resistance is a common finding in CHC, it is associated with increase liver steatosis. However it has no impact on EVR to combined interferon ribavirin therapy, viral load or necroinflammation. 相似文献
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Ibrahim Sabrin R. M. Abdallah Hossam M. El-Halawany Ali M. Mohamed Gamal A. 《Phytochemistry Reviews》2016,15(2):197-220
Phytochemistry Reviews - Thiophenes are a class of heterocyclic aromatic compounds based on a five-membered ring made up of one sulfur and four carbon atoms. The thiophene nucleus is well... 相似文献
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C. Brandon Ogbunugafor C. Scott Wylie Ibrahim Diakite Daniel M. Weinreich Daniel L. Hartl 《PLoS computational biology》2016,12(1)
The adaptive landscape analogy has found practical use in recent years, as many have explored how their understanding can inform therapeutic strategies that subvert the evolution of drug resistance. A major barrier to applications of these concepts is a lack of detail concerning how the environment affects adaptive landscape topography, and consequently, the outcome of drug treatment. Here we combine empirical data, evolutionary theory, and computer simulations towards dissecting adaptive landscape by environment interactions for the evolution of drug resistance in two dimensions—drug concentration and drug type. We do so by studying the resistance mediated by Plasmodium falciparum dihydrofolate reductase (DHFR) to two related inhibitors—pyrimethamine and cycloguanil—across a breadth of drug concentrations. We first examine whether the adaptive landscapes for the two drugs are consistent with common definitions of cross-resistance. We then reconstruct all accessible pathways across the landscape, observing how their structure changes with drug environment. We offer a mechanism for non-linearity in the topography of accessible pathways by calculating of the interaction between mutation effects and drug environment, which reveals rampant patterns of epistasis. We then simulate evolution in several different drug environments to observe how these individual mutation effects (and patterns of epistasis) influence paths taken at evolutionary “forks in the road” that dictate adaptive dynamics in silico. In doing so, we reveal how classic metrics like the IC50 and minimal inhibitory concentration (MIC) are dubious proxies for understanding how evolution will occur across drug environments. We also consider how the findings reveal ambiguities in the cross-resistance concept, as subtle differences in adaptive landscape topography between otherwise equivalent drugs can drive drastically different evolutionary outcomes. Summarizing, we discuss the results with regards to their basic contribution to the study of empirical adaptive landscapes, and in terms of how they inform new models for the evolution of drug resistance. 相似文献
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Peerzada Yasir Yousuf Altaf Ahmad Ibrahim M. Aref Munir Ozturk Hemant Arshid Hussain Ganie Muhammad Iqbal 《Protoplasma》2016,253(6):1565-1575
Brassica juncea is mainly cultivated in the arid and semi-arid regions of India where its production is significantly affected by soil salinity. Adequate knowledge of the mechanisms underlying the salt tolerance at sub-cellular levels must aid in developing the salt-tolerant plants. A proper functioning of chloroplasts under salinity conditions is highly desirable to maintain crop productivity. The adaptive molecular mechanisms offered by plants at the chloroplast level to cope with salinity stress must be a prime target in developing the salt-tolerant plants. In the present study, we have analyzed differential expression of chloroplast proteins in two Brassica juncea genotypes, Pusa Agrani (salt-sensitive) and CS-54 (salt-tolerant), under the effect of sodium chloride. The chloroplast proteins were isolated and resolved using 2DE, which facilitated identification and quantification of 12 proteins that differed in expression in the salt-tolerant and salt-sensitive genotypes. The identified proteins were related to a variety of chloroplast-associated molecular processes, including oxygen-evolving process, PS I and PS II functioning, Calvin cycle and redox homeostasis. Expression analysis of genes encoding differentially expressed proteins through real time PCR supported our findings with proteomic analysis. The study indicates that modulating the expression of chloroplast proteins associated with stabilization of photosystems and oxidative defence plays imperative roles in adaptation to salt stress. 相似文献