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1.
Heliyon ; 9(11): e22071, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38027785

RESUMO

Research Experience programs (REPs) inspire students to pursue advanced degrees and shape their research career paths. Government and commercial organizations sponsor REPs to promote the capacity building of the country. In Qatar, the national youth is reported to show concerning participation in Science, Technology, Engineering, and Mathematics (STEM) disciplines at the K-12 level. However, none of the studies investigate these participation trends at the undergraduate level, especially in scientific research, which is deemed necessary for building a knowledge-based economy in Qatar. Therefore, to bridge this gap, the current study uses a quantitative approach to analyze the REP in Qatar through the participation data of 2455 undergraduate students. For this, statistical measures, including descriptive analysis, independent samples t-test, and Pearson's correlation analysis were used. Results indicated concerning trends in national student participation rate, implying underlying issues restricting their representation in undergraduate research activities. Also, statistically significant differences were found in student participation rates among students' gender and ethnic distributions. While female students demonstrated higher participation rates than males, national students showed lower participation than the non-nationals. Moreover, this low participation of national students suffered more drastically in STEM disciplines. Therefore, these findings determine the outlook for stakeholders and academic institutions in making meaningful educational decisions and envision synchronizing REPs at the university level, gauging measures to bolster the adjacent funding agencies and government organizations. Furthermore, being the first research addressing REPs in the Middle East region, this study has the potential to support educators in neighboring and other developing nations where STEM education is especially significant for human capacity building.

2.
Molecules ; 27(24)2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36558052

RESUMO

Moringa oleifera is a traditional food crop widespread in Asiatic, African, and South American continents. The plant, able to grow in harsh conditions, shows a high nutritional value and medicinal potential evidencing cardioprotective, anti-inflammatory, antioxidant, and antimicrobial properties. The purpose of this study was the phytochemical analysis of M. oleifera and the identification of the antimicrobial compounds by combining a chemical approach with in vitro tests. The metabolite profile of M. oleifera polar and apolar extracts of leaves and seeds were investigated by using Nuclear Magnetic Resonance spectroscopy and Gas Chromatography-Mass Spectrometry. The antimicrobial activity of all of the obtained extract was evaluated against four bacterial pathogens (Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa and Salmonella enterica). The chemical analysis provided a wide set of metabolites that were identified and quantified. Moreover, apolar extracts from seeds showed a significant concentration-dependent antimicrobial activity against S. aureus and S. epidermidis, (4 mg/mL reduced the viability up to 50%) that was associated to the content of specific fatty acids. Our results remarked the advantages of an integrated approach for the identification of plant metabolites and its use in association with biological tests to recognize the compounds responsible for bioactivity without compounds purification.


Assuntos
Anti-Infecciosos , Moringa oleifera , Moringa oleifera/química , Staphylococcus aureus , Extratos Vegetais/química , Cromatografia Gasosa-Espectrometria de Massas , Sementes/química , Folhas de Planta/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/análise
3.
Travel Med Infect Dis ; 22: 46-50, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29409967

RESUMO

BACKGROUND: The epidemiology of extended-spectrum ß-lactamase (ESBL)-producing bacteria is fast evolving with increasing global trend towards community-acquired infections. Limited information available about ESBLs therapy outcomes and control strategies, especially in the Middle Eastern countries. METHODS: We studied 399 ESBL-producing Escherichia coli and Klebsiella pneumoniae isolates from urinary tract infections (UTIs) occurred between 2014 and 2016 in University Hospital Sharjah. We included 124 ESBL-negative E. coli and K. pneumoniae isolates from UTIs as controls. Pearson Chi squares test and independent t-test were used to compare difference between ESBL positives and negatives. Multivariate logistic regression analysis was also performed. RESULTS: Approximately 75% of the E. coli and K. pneumoniae isolates causing UTIs were community-acquired. We found that recurrent UTIs, old age, and catheterization among other risk factors for community-acquired ESBL-positive UTIs. Majority of these ESBL-positive isolates were resistant to antibiotics such as ciprofloxacin (74%) and trimethoprim-sulphamethoxazole (73%) that are commonly used for treatment of community-acquired urinary tract infections. CONCLUSIONS: ESBL-producing E. coli and K. pneumoniae have become major etiological pathogens of community-acquired UTIs in the United Arab Emirates. Healthcare providers should implement better infection control strategies and careful use of antimicrobials especially in out-patient and community settings.


Assuntos
Infecções Comunitárias Adquiridas/microbiologia , Escherichia coli/fisiologia , Klebsiella pneumoniae/fisiologia , Infecções Urinárias/microbiologia , Resistência beta-Lactâmica , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Infecções Comunitárias Adquiridas/tratamento farmacológico , Infecções Comunitárias Adquiridas/epidemiologia , Infecções Comunitárias Adquiridas/urina , Farmacorresistência Bacteriana Múltipla , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Feminino , Humanos , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/enzimologia , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Fatores de Risco , Emirados Árabes Unidos/epidemiologia , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/epidemiologia , Infecções Urinárias/urina
4.
Appl Radiat Isot ; 125: 139-143, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28432930

RESUMO

The present study focuses on the development of a new chemical treatment method for naturally occurring radioactive materials (NORM) scale wastes from the oil industry. The method consists of three-stages, including the separation of oil using the Fenton oxidation process at room temperature, the complete dissolution of soluble and slightly soluble salts and separation of Ra and Pb isotopes. The proposed method can be considered as an innovative procedure for NORM scales treatment and radionuclides separation, which in turn support the radioactive waste management with economic benefits.

5.
Dig Dis Sci ; 47(10): 2306-15, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12395904

RESUMO

Human colon has been suggested to play an important role in calcium absorption especially after extensive disease or resection of the small intestine. We have previously demonstrated the presence of a carrier-mediated calcium uptake mechanism in the human colonic luminal membrane vesicles. Current studies were, therefore, undertaken to investigate the mechanism(s) of calcium exit across the basolateral membrane domain of the human colon. Human colonic basolateral membrane vesicles (BLMVs) were isolated and purified from mucosal scrapings of organ donor colons, utilizing a technique developed in our laboratory. 45Ca uptake was measured by a rapid filtration technique. 45Ca uptake represented transport into the intravesicular space as evidenced by an osmolarity study and by the demonstration of Ca2' efflux from calcium preloaded vesicles by Ca2+ ionophore A23187. Calcium uptake was stimulated by Mg2+ ATP. The kinetic parameters for ATP-dependent Ca2+ uptake revealed saturation kinetics with Michaelis constant (Km) of 0.22 +/- 0.04 microM and a maximum rate of uptake (Vmax) of 0.38 +/- 0.12 nmol/mg protein/min. The Km of ATP concentration required for half maximal Ca2+ uptake was 0.39 +/- 0.04 mM. ATP-stimulated calcium uptake into these vesicles was further stimulated in the presence of calmodulin and was inhibited by calmodulin antagonist, trifluoperazine. Uptake of 45Ca into BLMVs was markedly inhibited by cis-Na+ but was significantly stimulated by trans-Na+ (40-50% stimulation). Our results demonstrate the presence of a Mg2+/ATP-dependent calmodulin-regulated Ca2+ transport system and a Na+-Ca2+ exchange process in the human colonic basolateral membranes.


Assuntos
Cálcio/fisiologia , Membrana Celular/fisiologia , Colo/fisiologia , Absorção Intestinal/fisiologia , Mucosa Intestinal/fisiologia , Vesículas Transportadoras/fisiologia , Trifosfato de Adenosina/fisiologia , ATPases Transportadoras de Cálcio/fisiologia , Humanos , ATPases Transportadoras de Cálcio da Membrana Plasmática , Trocador de Sódio e Cálcio/fisiologia , Equilíbrio Hidroeletrolítico/fisiologia
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