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1.
Int J Biol Macromol ; 264(Pt 2): 130668, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38453109

RESUMO

In this study, nanocomposite films were produced by blending polyvinyl alcohol (PVA) and chitosan (Cs) polymers with 70 % PVA and 30 % Cs, incorporating silver nanoparticles (Ag NPs) via a solution-casting method. The research aims to investigate the impact of the biosynthesized Ag NPs by Chenopodium murale leaf extract on optical, morphological, mechanical, thermal, electrical, and antibacterial properties. XRD analysis showed a decrease in crystallinity degree with Ag NPs addition. TEM revealed Ag NPs in cubic and spherical shapes with an average size of 23.4 nm. SEM and AFM indicated surface morphology changes. FT-IR spectra showed interaction between Ag ions and the blend. The energy gap decreased with increasing Ag NPs concentration. TGA exhibited enhanced thermal stability. Mechanical properties improved significantly. AC electrical conductivity and dielectric parameters were studied. Antibacterial activity against Gram-positive and Gram-negative bacteria was observed. Overall, PVA/Cs-Ag NPs films show promise for food packaging and optoelectronic applications.


Assuntos
Quitosana , Nanopartículas Metálicas , Nanocompostos , Antibacterianos/farmacologia , Prata , Álcool de Polivinil , Embalagem de Alimentos , Espectroscopia de Infravermelho com Transformada de Fourier , Bactérias Gram-Negativas , Bactérias Gram-Positivas
2.
Int J Biol Macromol ; 254(Pt 2): 127894, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37931864

RESUMO

Organic/Inorganic nanostructures enable the development of new functional materials for optoelectronics and biological applications. In this work, nanocomposite films of polyvinyl pyrrolidone (PVP) and sodium alginate (NaAlg) blend matrix (30/70 wt%) filled with molybdenum trioxide (MoO3) nanoplates were prepared using solution casting procedure. The effect of MoO3 nanoplates on structural, optical, electrical and antibacterial characteristics of pure PVP/NaAlg blend was investigated. The sizes of MoO3 nanoplates had dimensions between 90 and 420 nm with orthorhombic phase as indicated by the TEM and XRD techniques. Also, the XRD patterns of filled films suggested that the presence of crystalline phases of MoO3 within PVP/NaAlg matrix. FTIR analysis revealed the primary vibrational peaks of PVP and NaAlg, whose strength altered randomly after filling. The UV absorption increased gradually and shifted to the higher wavelength side. The alternating current (AC) conductivity and dielectric parameters were improved with increasing MoO3 concentration. The antibacterial activity against Staphylococcus aureus and Escherichia coli increased with increase of MoO3 nanoplates concentration. The filled PVP/NaAlg-MoO3 samples displayed considerable enhancements in the values of Young's modulus (Y), tensile stress (σt) and elongation at break (εB). The obtained results imply that these nanocomposite films can be potentially used in optoelectronics and biological applications.


Assuntos
Nanocompostos , Polímeros , Povidona , Polivinil , Alginatos/química , Antibacterianos/farmacologia , Antibacterianos/química , Nanocompostos/química
3.
Acta Diabetol ; 60(2): 203-210, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36305978

RESUMO

AIMS: The present study focused on identifying the current prevalence of diabetes mellitus (DM) in rural desert and rural agricultural areas of Egypt and comparing these findings to those of previous studies that reported lower prevalence rates of DM in rural desert versus rural agricultural areas. METHODS: The study included a total of 15,000 participants aged 20 years or older; 10,000 were from rural agricultural areas and 5000 were from rural desert areas in Egypt. The prevalence of DM and impaired fasting glucose for each group was recorded, participants were interviewed, medical history was obtained, physical examinations were performed, and fasting plasma glucose was used for diagnosis of DM and IFG using American Diabetes Association criteria. RESULTS: The prevalence of DM was 12.7% in agricultural areas and 4.7% in desert areas. The prevalence of newly diagnosed cases was 15.8% and 9.9% in agricultural and desert areas, respectively. The prevalence of IFG was 11.14% in agricultural and 8.04% in desert areas. These results suggest that living in a rural area makes patients at a higher risk of developing DM (OR = 2.968 CI (2.570-3.428) p < 0.001) and IFG (OR = 1.43, CI (1.272-1.616), p < 0.001). Logistic regression analysis revealed that increased age, living in agricultural areas, higher body mass index and positive family history of diabetes were the significant predictors affecting the prevalence of DM. CONCLUSIONS: The prevalence of DM, IFG, and overall dysglycemia (DM + IFG) in Egypt has generally increased in rural areas, with a lower prevalence in rural desert compared to rural agricultural areas.


Assuntos
Diabetes Mellitus , Estado Pré-Diabético , Adulto , Humanos , Egito/epidemiologia , Glicemia , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , Jejum , Prevalência , Fatores de Risco
4.
Materials (Basel) ; 15(20)2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36295300

RESUMO

The native oxide layer that forms on copper (Cu) metal spherical particle surfaces under ambient handling conditions has been shown to have a significant effect on sintering behavior during microwave heating in a previous study, where an abnormal expansion was observed and characterized during sintering of Cu compacts using reducing gases. Because microwave (MW) heating is selective and depends greatly on the dielectric properties of the materials, this thin oxide layer will absorb MW energy easily and can consequently be heated drastically starting from room temperature until the reduction process occurs. In the current study, this oxide ceramic layer was qualitatively and quantitatively characterized using the carrier gas hot extraction (CGHE) method, Auger electron spectroscopy (AES), and a dual-beam focused ion beam (FIB)/scanning electron microscope (SEM) system that combines both FIB and SEM in one single instrument. Two different commercial gas-atomized spherical Cu metal powders with different particle sizes were investigated, where the average oxygen content of the powders was found to be around 0.575 wt% using the CGHE technique. Furthermore, AES spectra along with depth profile measurements were used to qualitatively characterize this oxide layer, with only a rough quantitative thickness approximation due to method limitations and the electron beam reduction effect. For the dual-beam FIB-SEM system, a platinum (Pt) coating was first deposited on the Cu particle surfaces prior to any characterization in order to protect and to preserve the oxide layer from any possible beam-induced reduction. Subsequently, the Pt-coated Cu particles were then cross-sectioned in the middle in situ using an FIB beam, where SEM micrographs of the resulted fresh sections were characterized at a 36° angle stage tilt with four different detector modes. Quantitative thickness characterization of this native oxide layer was successfully achieved using the adapted dual-beam FIB-SEM setup with more accuracy. Overall, the native Cu oxide layer was found to be inhomogeneous over the particles, and its thickness was strongly dependent on particle size. The thickness ranged from around 22-67 nm for Cu powder with a 10 µm average particle size (APS) and around 850-1050 nm for one with less than 149 µm.

5.
Biosci. j. (Online) ; 36(3): 1024-1031, 01-05-2020. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-1147195

RESUMO

Halophilic bacteria are microorganisms that grow optimally in the presence of the very high concentration of sodium chloride. Halophiles are vital sources of various enzymes including hydrolases, which are very stable and catalytically highly efficient at high salt concentration and other extreme conditions such as high temperature, pH and presence of organic solvents. Several hydrolases such as amylases, proteases, and lipases have been obtained from halophilic bacteria and are commonly used for various industrial applications. We initiated a screening to isolate and characterize the halophilic bacteria from the Red Sea, which is one of the saltiest bodies of water in the world. Water and soil samples, collected from the Red Sea coast, Jeddah, Saudi Arabia, were screened for isolation of halophilic bacteria. Ten bacterial isolates were obtained, which were characterized by biochemical tests and 16S rRNA gene sequencing. Hydrolase producing bacteria among the isolates were screened by plate assay on starch and gelatin agar plates for amylase and protease, respectively. Two bacterial isolates i.e. Bacillus glycinifermentans S3 and Enterobacter cloacae W1were found to possess significant amylase and protease activity.


Bactérias halofílicas são microrganismos que crescem de maneira ideal na presença de uma concentração muito alta de cloreto de sódio. Halófilos são fontes vitais de várias enzimas, incluindo hidrolases, que são muito estáveis e cataliticamente altamente eficientes em alta concentração de sal e outras condições extremas, como alta temperatura, pH e presença de solventes orgânicos. Várias hidrolases como amilases, proteases e lipases foram obtidas a partir de bactérias halofílicas e são comumente usadas para várias aplicações industriais. Iniciamos uma triagem para isolar e caracterizar as bactérias halofílicas do Mar Vermelho, que é um dos corpos de água mais salgados do mundo. Amostras de água e solo, coletadas na costa do Mar Vermelho, Jeddah, na Arábia Saudita, foram examinadas quanto ao isolamento de bactérias halofílicas. Foram obtidos dez isolados bacterianos, caracterizados por testes bioquímicos e seqüenciamento do gene 16S rRNA. As bactérias produtoras de hidrolase entre os isolados foram triadas por ensaio em placa em placas de amido e ágar de gelatina para amilase e protease, respectivamente. Verificou-se que dois isolados bacterianos, isto é, Bacillus glycinifermentans S3 e Enterobacter cloacae W1, possuíam significativa atividade de amilase e protease.


Assuntos
Peptídeo Hidrolases , Halobacteriales , Salinidade , Amilases , Hidrolases
8.
Saudi Med J ; 39(12): 1186-1194, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30520499

RESUMO

OBJECTIVES: To explore the risk factors, the prevalence rate, and gene types of extended-spectrum beta-lactamase (ESBL)-producing bacteria as the causative agents of infection at King Abdulaziz Specialist Hospital (KAASH), Taif, Kingdom of Saudi Arabia. Methods: This was a retrospective study conducted during the period between February 2017 and January 2018. All samples obtained from the KAASH were analyzed. The MicroScan Walkaway System, bacteriological examination and double disk synergy tests were used to detect ESBL-producing bacteria. To identify ESBL genes, the polymerase chain reaction (PCR) technique was used. Results: The ESBL phenotype was detected in 351 of 1151 isolates (30.5%); Escherichia coli (E. coli) (62.7%) and Klebsiella pneumoniae (K. pneumoniae) (23.6%) were the most prevalent. The highest proportion of ESBL specimens was found in urine (62%.5), and these organisms were mainly isolated from the female medical ward (20.2%). Based on the statistical analysis, lung diseases, renal diseases, diabetes and heart diseases contributed to the spread of ESBL infections. Amikacin, imipenem, meropenem and tigecycline were found to be effective in overcoming ESBL infections; however, these antibiotics may be inappropriate for new strains of K.pneumoniae. The distribution of the blaCTX-M gene was high (87%), compared with blaTEM (74.9%) and blaSHV (29.4%).   Conclusion: These data provide new epidemiological information about the prevalence of ESBL-producing organisms among patients in KAASH, Taif, Saudi Arabia. In addition, this study identified the clonal nature of isolated E.coli and K.pneumoniae.


Assuntos
Infecções por Escherichia coli/epidemiologia , Escherichia coli/genética , Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae/genética , beta-Lactamases/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteínas de Bactérias/genética , Criança , Pré-Escolar , Diabetes Mellitus/epidemiologia , Infecções por Escherichia coli/microbiologia , Feminino , Genótipo , Cardiopatias/epidemiologia , Humanos , Lactente , Recém-Nascido , Nefropatias/epidemiologia , Infecções por Klebsiella/microbiologia , Pneumopatias/epidemiologia , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Prevalência , Estudos Retrospectivos , Fatores de Risco , Arábia Saudita/epidemiologia , Adulto Jovem
9.
Asian J Androl ; 20(3): 284-289, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29111540

RESUMO

To investigate whether transcription of hepatitis B virus (HBV) gene occurs in human sperm, total RNA was extracted from sperm of patients with chronic HBV infection (test-1), from donor sperm transfected with a plasmid containing the full-length HBV genome (test-2), and from nontransfected donor sperm (control), used as the template for reverse transcription-polymerase chain reaction (RT-PCR). Positive bands for HBV DNA were observed in the test groups but not in the control. Next, to identify the role of host genes in regulating viral gene transcription in sperm, total RNA was extracted from 2-cell embryos derived from hamster oocytes fertilized in vitro by HBV-transfected (test) or nontransfected (control) human sperm and successively subjected to SMART-PCR, suppression subtractive hybridization, T/A cloning, bacterial amplification, microarray hybridization, sequencing and the Basic Local Alignment Search Tool (BLAST) search to isolate differentially expressed genes. Twenty-nine sequences showing significant identity to five human gene families were identified, with chorionic somatomammotropin hormone 2 (CSH2), eukaryotic translation initiation factor 4 gamma 2 (EIF4G2), pterin-4 alpha-carbinolamine dehydratase 2 (PCBD2), pregnancy-specific beta-1-glycoprotein 4 (PSG4) and titin (TTN) selected to represent target genes. Using real-time quantitative RT-PCR (qRT-PCR), when CSH2 and PCBD2 (or EIF4G2, PSG4 and TTN) were silenced by RNA interference, transcriptional levels of HBV s and x genes significantly decreased (or increased) (P < 0.05). Silencing of a control gene in sperm did not significantly change transcription of HBV s and x genes (P > 0.05). This study provides the first experimental evidence that transcription of HBV genes occurs in human sperm and is regulated by host genes.


Assuntos
Hormônio do Crescimento/genética , Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B/genética , Hepatite B Crônica/virologia , Espermatozoides/virologia , Transativadores/genética , Transcrição Gênica , Animais , Conectina/genética , Cricetinae , Fator de Iniciação 4G em Eucariotos/genética , Regulação da Expressão Gênica/genética , Inativação Gênica , Humanos , Hidroliases/metabolismo , Masculino , Glicoproteínas beta 1 Específicas da Gravidez/genética , RNA Viral/análise , Transfecção , Proteínas Virais Reguladoras e Acessórias
10.
Reprod Toxicol ; 73: 158-166, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28822827

RESUMO

Hepatitis B virus (HBV) can invade the male germline, and sperm-introduced HBV genes could be transcribed in embryo. This study was to explore whether viral gene transcription is regulated by host genes. Embryos were produced by in vitro fertilization of hamster oocytes with human sperm containing the HBV genome. Total RNA extracted from test and control embryos were subjected to SMART-PCR, SSH, microarray hybridization, sequencing and BLAST analysis. Twenty-nine sequences showing significant identity to five human gene families were identified, with CSH2, EIF4G2, PCBD2, PSG4 and TTN selected to represent target genes. Using qRT-PCR, when CSH2 and PCBD2 (or EIF4G2, PSG4 and TTN) were silenced by RNAi, transcriptional levels of HBV s and x genes decreased (or increased). This is the first report that host genes participate in regulation of sperm-introduced HBV gene transcription in embryo, which is critical to prevent negative impact of HBV infection on early embryonic development.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Genes Virais , Vírus da Hepatite B/genética , Espermatozoides/virologia , Embrião de Mamíferos , Humanos , Masculino
11.
Acta Chim Slov ; 63(3): 609-18, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27640388

RESUMO

A series of pyrimidine and thiazine derivatives was synthesized by one-pot reaction of cyclopentanone with a mixture of an aromatic aldehyde, namely o-anisaldehyde, and different ureas, namely urea, guanidine and thiourea, respectively. Furthermore, cycloaddition reaction of active methylene reagents, namely acetyl acetone, malononitrile, ethyl cyanoacetate, cyanoacetamide and N-phenyl cyanoacetamide with 2,6-bis(2-methoxybenzylidene)cyclohexanone afforded chromene and quinoline derivatives in basic medium. The antitumor evaluation of some new compounds against three human cell lines, namely MCF-7, NCI-H460 and SF-268 showed significant and moderate activity compared with the positive control doxorubicin.


Assuntos
Cetonas/síntese química , Cetonas/farmacologia , Linhagem Celular Tumoral , Ciclização , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Cetonas/química , Espectroscopia de Prótons por Ressonância Magnética
12.
East Mediterr Health J ; 22(2): 103-15, 2016 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-27180738

RESUMO

There is an increasing burden of obesity and obesity-related noncommunicable diseases in Gulf Cooperation Council countries, including Oman. This descriptive, epidemiological study assessed physical activity among 2977 Omani adults using a population-based household survey in 2008. Overall, 54.2% of men and 41.6% of women were physically active; the rate was higher in younger cohorts and varied significantly by region of residence. Physical activity related to the transportation (walking and cycling) domain was higher than in the leisure or work domains. Unmarried men aged 30-39 years were twice as likely to be physically active (OR 2.25) and unmarried women aged 40+ years were half as likely to be active (OR 0.58) than their married counterparts. Young women not working were less active (OR 0.18) than working women. Higher education was significantly associated with leisure activity for men aged 30+ years and women aged 40+ years. Further research to understand regional variations and to identify culturally appropriate strategies to promote physical activity is required.


Assuntos
Exercício Físico , Inquéritos Epidemiológicos , Adulto , Distribuição por Idade , Feminino , Inquéritos Epidemiológicos/estatística & dados numéricos , Humanos , Modelos Logísticos , Masculino , Omã , Distribuição por Sexo
13.
Materials (Basel) ; 9(7)2016 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-28773627

RESUMO

Lithium aluminum germanium phosphate (LAGP) glass-ceramics are considered as promising solid-state electrolytes for Li-ion batteries. LAGP glass was prepared via the regular conventional melt-quenching method. Thermal, chemical analyses and X-ray diffraction (XRD) were performed to characterize the prepared glass. The crystallization of the prepared LAGP glass was done using conventional heating and high frequency microwave (MW) processing. Thirty GHz microwave (MW) processing setup were used to convert the prepared LAGP glass into glass-ceramics and compared with the conventionally crystallized LAGP glass-ceramics that were heat-treated in an electric conventional furnace. The ionic conductivities of the LAGP samples obtained from the two different routes were measured using impedance spectroscopy. These samples were also characterized using XRD and scanning electron microscopy (SEM). Microwave processing was successfully used to crystallize LAGP glass into glass-ceramic without the aid of susceptors. The MW treated sample showed higher total, grains and grain boundary ionic conductivities values, lower activation energy and relatively larger-grained microstructure with less porosity compared to the corresponding conventionally treated sample at the same optimized heat-treatment conditions. The enhanced total, grains and grain boundary ionic conductivities values along with the reduced activation energy that were observed in the MW treated sample was considered as an experimental evidence for the existence of the microwave effect in LAGP crystallization process. MW processing is a promising candidate technology for the production of solid-state electrolytes for Li-ion battery.

14.
East. Mediterr. health j ; 22(2): 103-115, 2016.
Artigo em Inglês | WHO IRIS | ID: who-255117

RESUMO

هناك تزايد في عبء السمنه والامراض غير الساريه المرتبطة بالسمنه في بلدان مجلس التعاون الخليجي بما فيها سلطنه عمان وقد قيمت هذه الدراسة الوبائيه الوصفيه النشاط البدني لدى 2977 بالغا عمانيا باستخدام مسح اسري سكاني في عام 2008 فكان بالاجمال 54.2% من الرجال و 41.6% من النساء نشيطين بدنيا وكان المعدل أعلى لدى الفئات الاصغر سنا وشديد التباين باختلاف منطقة الاقامه وكان النشاط البدني المرتبط بمجال المواصلات ( المشي وركوب الدراجات ) اعلى من النشاط الذي يبذل في مجالات الترفيه او العمل وكان النشاط البدني لدي الرجال غير المتزوجين ممن هم باعمار 39-30 عاما ضعف نشاط نظرائهم المتزوجين OR=2.25 ولدي النساء غير المتزوجات اللواتي تجاوزن الـ 40 سنه نصف نشاط نظيراتهن المتزوجات OR=0.58 وكانت الشابات اللواتي لايعملن اقل نشاطا OR=0.18 من النساء العاملات وكان هناك ارتباط كبير بين التعليم العالي وبين النشاط الترفيهي لدى الرجال الذين تزيد اعمارهم عن 30 سنه والنساء اللواتي تجاوزن الـ 40 سنه هناك حاجة الى مزيد من البحوث لفهم التباينات الاقليميه ولتحديد استراتيجيات ملائمه ثقافيا لتعزيز النشاط البدني


There is an increasing burden of obesity and obesity-related noncommunicable diseases in Gulf Cooperation Council countries, including Oman. This descriptive, epidemiological study assessed physical activity among 2977 Omani adults using a population-based household survey in 2008. Overall, 54.2% of men and41.6% of women were physically active; the rate was higher in younger cohorts and varied significantly by region of residence. Physical activity related to the transportation (walking and cycling) domain was higher than in the leisure or work domains. Unmarried men aged 30–39 years were twice as likely to be physically active (OR 2.25) and unmarried women aged 40+ years were half as likely to be active (OR 0.58) than their married counterparts. Young women not working were less active (OR 0.18) than working women. Higher education was significantlyassociated with leisure activity for men aged 30+ years and women aged 40+ years. Further research to understand regional variations and to identify culturally appropriate strategies to promote physical activity is required.


Le fardeau de l’obésité et des maladies non transmissibles liées à l’obésité est en augmentation dans les pays du Conseil de Coopération du Golfe, notamment à Oman. La présente étude épidémiologique descriptive a évalué l’activité physique de 2977 adultes omanais à l’aide d’une enquête de population auprès des ménagesen 2008. Globalement, 54,2 % des hommes et 41,6 % des femmes avaient une activité physique ; le taux était supérieur dans les cohortes plus jeunes et variait significativement en fonction de la région de résidence. L’activité physique liée aux déplacements (marche et vélo) était plus fréquente que l’activité physique professionnelle ou de loisir. Les hommes célibataires entre 30 et 39 ans étaient deux fois plus susceptibles d’être physiquement actifs (OR 2,25) alors que les femmes célibataires âgées de plus de 40 ans étaient deux fois moins actives (OR0,58) que les femmes mariées. Les femmes jeunes sans emploi étaient moins actives physiquement (OR 0,18) que les femmes occupant un emploi. Un niveau d’études supérieur était nettement associé à une activité physique de loisir chez les hommes de plus de 30 ans et les femmes de plus de 40 ans. Des recherches plus approfondies pour comprendre les variations régionales et identifier des stratégies culturellement appropriées visant à promouvoir l’activité physique sont nécessaires.


Assuntos
Atividade Motora , Epidemiologia , Inquéritos Epidemiológicos , Inquéritos e Questionários , Organização Mundial da Saúde
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 145: 376-383, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25795612

RESUMO

The effects of carbon, Fe2O3 and Na2SO4 contents on the amber color of glass with composition (wt%) 64.3 SiO2, 25.7 CaO, 10 Na2O were studied. The effect of some additives that could be found in glass batch or cullets on the amber related absorption band(s) was also studied. An amber related absorption band due to the chromophore Fe(3+)O3S(2-) was recorded at 420 nm with shoulder at 440 nm. A second amber related band recorded at 474 nm with shoulder at 483 nm was assigned to FeS. Increasing melting time at 1400°C up to 6h caused fainting of the amber color, decreases the intensities of the amber related bands and shifted the first band to 406 nm. Addition of ZnO, Cu2O and NaNO3 to the glass produced decolorizing effect and vanishing of the amber related bands. The effects of melting time and these additives were explained on the bases of destruction the amber chromophore and its conversion into Fe(3+) in tetrahedral sites or ZnS. Addition of Se intensifies the amber related bands and may cause dark coloration due to the formation of Se° and polyselenide. Amber color can be monitored through measuring the absorption in the range 406-420 nm.


Assuntos
Absorção Fisico-Química , Vidro/química , Silicatos/química , Cor , Cobre/química , Compostos Férricos/química , Nitratos/química , Substâncias Redutoras/química , Selênio/química , Espectrofotometria Ultravioleta , Espectroscopia de Luz Próxima ao Infravermelho , Fatores de Tempo , Óxido de Zinco/química
16.
Microb Cell Fact ; 13: 141, 2014 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-25270715

RESUMO

The rapid increase in the number of diabetic patients globally and exploration of alternate insulin delivery methods such as inhalation or oral route that rely on higher doses, is bound to escalate the demand for recombinant insulin in near future. Current manufacturing technologies would be unable to meet the growing demand of affordable insulin due to limitation in production capacity and high production cost. Manufacturing of therapeutic recombinant proteins require an appropriate host organism with efficient machinery for posttranslational modifications and protein refolding. Recombinant human insulin has been produced predominantly using E. coli and Saccharomyces cerevisiae for therapeutic use in human. We would focus in this review, on various approaches that can be exploited to increase the production of a biologically active insulin and its analogues in E. coli and yeast. Transgenic plants are also very attractive expression system, which can be exploited to produce insulin in large quantities for therapeutic use in human. Plant-based expression system hold tremendous potential for high-capacity production of insulin in very cost-effective manner. Very high level of expression of biologically active proinsulin in seeds or leaves with long-term stability, offers a low-cost technology for both injectable as well as oral delivery of proinsulin.


Assuntos
Escherichia coli , Plantas Geneticamente Modificadas , Proinsulina , Saccharomyces cerevisiae , Escherichia coli/genética , Escherichia coli/metabolismo , Humanos , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Proinsulina/biossíntese , Proinsulina/genética , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
17.
East Mediterr Health J ; 19(2): 181-5, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23516830

RESUMO

The role of inflammatory cytokines in the pathophysiology of beta-thalassaemia is still unclear. In this study production levels of interleukins (IL)-12 and IL-13 were measured by commercial ELISA in culture supernatants of mitogen-stimulated peripheral blood mononuclear cells-from 30 non-splenectomized beta-thalassaemia cases with iron overload and 20 age- and sex-matched healthy individuals. IL-12 levels were significantly lower among cases compared with controls (91.4 pg/mL versus 154.6 pg/mL), while IL-13 levels were significantly higher (42.5 pg/mL versus 5.7 pg/mL). There was a significant negative correlation between IL-12 and lL-13 levels among beta-thalassaemia cases (r= -0.42). Patients with beta-thalassaemia alone had higher IL-12 levels than beta-thalassaemia patients who were seropositive for chronic hepatitis B or C virus infection (140 pg/mL versus 50 pg/mL); IL-13 levels were slightly lower (65 pg/mL versus 67 pg/mL). An imbalance in the IL-12/IL-13 axis may be relevant to the pathophysiology of beta-thalassaemia.


Assuntos
Interleucina-12/sangue , Interleucina-13/sangue , Talassemia beta/sangue , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Humanos , Masculino , Adulto Jovem
18.
East Mediterr Health J ; 19(7): 676-81, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24975315

RESUMO

To test the role of T helper cell Th1 immunity we recruited 24 patients with idiopathic thrombocytopenia associated with H. pylori seropositivity. They were divided into 2 groups: 12 with immune-mediated thrombocytopenia (Group 1) and 12 with non-immune mediated thrombocytopenia (Group 2). We also recruited 10 individuals seronegative for H. pylori (Group 3) as controls. Initial platelet count was significantly lower in Group 1 than Group 2. H. pylori was eradicated in 10 of 12 patients in Group 1 and in all patients in Group 2. Transient improvement (< 3 months) in the platelet count occurred in only 2 patients in Group 1 while improvement for > 6 months was observed in all patients in Group 2. There was a statistically significant direct correlation between platelet count and levels of TNF- and IFN-gamma in both study groups, while a non-significant correlation was seen in Group 3. Thus, H. pylori infection should be considered in the differential diagnosis of all cases of thrombocytopenia, and should be eradicated in all H. pylori-positive patients with thrombocytopenia.


Assuntos
Infecções por Helicobacter/complicações , Helicobacter pylori/isolamento & purificação , Contagem de Plaquetas/estatística & dados numéricos , Púrpura Trombocitopênica Idiopática/microbiologia , Adolescente , Adulto , Análise de Variância , Estudos de Casos e Controles , Doença Crônica , Egito , Feminino , Infecções por Helicobacter/imunologia , Helicobacter pylori/imunologia , Humanos , Masculino , Púrpura Trombocitopênica Idiopática/sangue , Púrpura Trombocitopênica Idiopática/imunologia , Adulto Jovem
19.
East Mediterr Health J ; 19(5): 490-4, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-24617130

RESUMO

This study was designed to estimate interferon-gamma (INF-gamma) levels among polytransfused haematology cases. Cases were selected from the haematology unit of Alexandria main university hospital, Egypt. Complete blood counts, estimation of INF-gamma and hepatitis B and C virus (HBV and HCV) status were conducted on 20 unsplenectomized patients with gamma-thalassaemia major and 20 patients with acute myeloid leukaemia (AML) in the maintenance phase and 20 healthy subjects. Mean haemoglobin levels and red blood cell counts were significantly higher in the control group than the AML and thalassaemia groups, while white blood cell counts were significantly lower in the control group than the case groups. Two AML patients (10%) and 1 thalassaemia patient (5%) were HBV-positive, while 5% of both case groups were HCV-positive. Mean values of INF-gamma were significantly different between AML, thalassaemia major and control groups: 5517 (SD 1142) pg/mL, 1024 (SD 249) pg/mL and 2980 (SD 604) pg/mL respectively.


Assuntos
Transfusão de Sangue/estatística & dados numéricos , Interferon gama/sangue , Leucemia Mieloide Aguda/sangue , Talassemia beta/sangue , Estudos de Casos e Controles , Egito , Contagem de Eritrócitos , Hemoglobinas/análise , Hepacivirus/isolamento & purificação , Vírus da Hepatite B/isolamento & purificação , Humanos , Leucemia Mieloide Aguda/terapia , Contagem de Leucócitos , Reação Transfusional , Talassemia beta/terapia
20.
(East. Mediterr. health j).
em Inglês | WHO IRIS | ID: who-118570

RESUMO

To test the role of T helper cell Th1 immunity we recruited 24 patients with idiopathic thrombocytopenia associated with H. pylori seropositivity. They were divided into 2 groups: 12 with immune-mediated thrombocytopenia [Group 1] and 12 with non-immune mediated thrombocytopenia [Group 2]. We also recruited 10 individuals seronegative for H. pylori [Group 3] as controls. Initial platelet count was significantly lower in Group 1 than Group 2. H. pyloriwas eradicated in 10 of 12 patients in Group 1 and in all patients in Group 2. Transient improvement [< 3 months] in the platelet count occurred in only 2 patients in Group 1 while improvement for > 6 months was observed in all patients in Group 2. There was a statistically significant direct correlation between platelet count and levels of TNF- and IFN-gamma in both study groups, while a non-significant correlation was seen in Group 3. Thus, H. pyloriinfection should be considered in the differential diagnosis of all cases of thrombocytopenia, and should be eradicated in all H. pylori-positive patients with thrombocytopenia


Assuntos
Helicobacter pylori , Imunidade , Contagem de Plaquetas , Linfócitos T Auxiliares-Indutores , Fator de Necrose Tumoral alfa , Interferon gama , Trombocitopenia
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