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1.
Nanotechnology ; 31(36): 365404, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32470955

RESUMO

Synthesis of rational nanostructure design of hybrid materials including uniformly growing, stable and highly porous structures have received a great deal of attention for many energy storage applications. In this study, the positive electrode of the uniform distribution of NiCo2O4 nanorods anchored on carbon nanofibers has been successfully prepared by in-situ growth under the hydrothermal process. Whereas, the activated multichannel carbon nanofibers (AMCNFs) have been fabricated via electrospinning followed by alkaline activation as the negative electrode. The crystal phase, morphological structure for the proposed electrode materials were characterized by x-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Moreover, the electrochemical behaviors were investigated using cyclic voltammetry (CV), galvanostatic charge and discharge (GCD) and electrochemical impedance spectroscopy (EIS) measurements. Compared to the neat CNFs and the pristine NiCo2O4, the NiCo2O4@CNFs hybrid electrodes showed better electrochemical performance and achieved a high specific capacitance up to 649 F g-1 at a current density of 3 A g-1. The optimized NiCo2O4@CNFs//AMCNFs asymmetric device achieved a high energy density of 38.5 Wh kg-1 with a power density of 1.6 kW kg-1 and possessed excellent recyclability with 93.1% capacitance retention over 6000 charging/discharging cycles. Overall, the proposed study introduces a facile strategy for the robust design of hybrid structured as effective nanomaterials based electrode for high-performance electrochemical supercapacitors.

2.
Nanotechnology ; 31(18): 185403, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31952052

RESUMO

This work aims to develop and characterize a new design of free-standing interconnected carbon nanofiber electrodes for supercapacitor application. The fibers are obtained via carbonization of three components of electrospun nanofiber mats based on a polyacrylonitrile polymer (as a carbon backbone precursor), polyvinylalcohol (as a sacrificial copolymer), and 0-1.0 wt% multi-walled carbon nanotubes. Carbonizing these ternary composites results in fibers with about twice as large in surface area and one order of magnitude higher in electrical conductivity than those obtained by the carbonization of neat polyacrylonitrile and/or binary polyacrylonitrile-0-1.0 wt% carbon nanotube mats. The carbonized polyacrylonitrile-polyvinylalcohol-0.3 wt% carbon nanotube mat reveals the highest surface area and electrical conductivity and best capacitive performance. It exhibits energy and power densities of 27.8 Wh kg-1 and 110.59 kW kg-1, respectively, and cyclic stability of 95% after 2000 charge-discharge cycles at a charging current of 1.0 Ag-1. The nanotubes' alignment along the fiber's axis, the formation of fiber-fiber interconnected morphology with more mesopore pollution, and changes in the graphitization degree and defect features of fiber crystallites are the reasons for the observed increase in the electrical conductivity, surface area, and capacitive performance of the carbon fibers. Therefore, the new design represents a potential free-standing carbon nanofiber electrode for future electrochemical double layer capacitor (EDLC) device fabrication.

3.
Allergol Immunopathol (Madr) ; 40(5): 275-80, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21889830

RESUMO

BACKGROUND: Angiotensin converting enzyme (ACE) is expressed at high levels in the lungs and plays a role in the metabolism of the endogenous peptides involved in asthma pathogenesis. ACE gene polymorphisms have been reported to be linked to asthma. However, the results are conflicting, with no reported studies on Egyptian asthmatics. We aimed to assess ACE gene polymorphism among Egyptian asthmatics, and to determine its possible association with asthma severity. METHODS: This case-control study was conducted on 30 adult asthmatic patients, and 30 healthy controls with no history of asthma or atopy. Atopic status among asthmatics was determined by skin prick test (SPT). Lung functions were assessed by spirometry. Determination of ACE genotypes was performed for all subjects. Total serum IgE levels were measured by ELISA. RESULTS: The frequencies of the DD, ID and II genotypes were 46.7%, 40%, and 13.3%, respectively among the cases, and 33.3%, 40%, and 26.7%, respectively among the controls. No significant differences in ACE genotype distribution were observed between cases and controls (p=0.37). Genotype distribution did not differ according to age of onset or severity of asthma, total serum IgE levels, SPT positivity, or number of positive SPT reactions. Furthermore, ACE polymorphism was not statistically different between asthmatic patients without any associated atopic disease and those with an associated atopic disease. CONCLUSION: The results of our study indicate that ACE gene polymorphism is not significantly associated with bronchial asthma or with its severity among Egyptian adults.


Assuntos
Asma/genética , Predisposição Genética para Doença , Peptidil Dipeptidase A/genética , Polimorfismo Genético , Adulto , Estudos de Casos e Controles , Análise Mutacional de DNA , Egito , Feminino , Frequência do Gene , Estudos de Associação Genética , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Adulto Jovem
4.
Andrologia ; 43(2): 94-9, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21382062

RESUMO

This study aimed to illustrate the histological picture of the developing rat prostate and to localise the oestrogen receptors (ERs) distribution. Fifty male albino rats were divided into five equal subgroups: subgroup 1, rats aged 2 days (before morphogenesis of prostate from urogenital sinus); subgroup 2, rats aged 1 week (after early morphogenesis); subgroup 3, rats aged 2 weeks (early pubertal stage); subgroup 4, rats aged 4 weeks (late pubertal stage) and subgroup 5 rats aged 6 weeks (maturation stage). After the rats had been killed, the prostates were dissected and specimens were obtained from the anterior lobe. Paraffin sections of these specimens were subjected to haematoxylin and eosin stain, immunohistochemistry and quantitative immunohistochemistry for ERs distribution and the area of strong positive cytoplasmic immunoreactivity. The results demonstrated that ERs protein decreased gradually with increased age and that it decreased markedly with the onset of puberty. It is concluded that the prostate despite being an androgen dependent gland, depends greatly on oestrogen in its development in the prepubertal period.


Assuntos
Próstata/química , Próstata/crescimento & desenvolvimento , Receptores de Estrogênio/análise , Animais , Núcleo Celular/química , Citoplasma/química , Epitélio/química , Imuno-Histoquímica , Masculino , Próstata/ultraestrutura , Ratos , Maturidade Sexual , Células Estromais/química
5.
Trop Anim Health Prod ; 40(5): 349-55, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18509943

RESUMO

This review discusses the historical, developmental and practices of ostrich farming in Egypt. In the early 20th century, ostrich farming was very important for production of ostrich feathers and documents were produced to perfect the art of procuring the plumes from the birds and subsequently processing them. Pharaohs used ostrich feathers for adornment. Of 43 provinces, 12 were featured in 2003-2004 as farming ostriches: Alexandria, Al-Behera, Al-Dakahlia, Al-Wadi Al-Gadid, Aswan, Cairo, El-Sharkia, Geiza, Ismailia, Kafr-El-Sheikh, Matrouh and Nubaria. Abattoirs and tanneries specialising in ostrich handling are limited to two. Egypt has numerous strengths and opportunities to develop its ostrich sector. Rising meat prices suggest that fresh ostrich meat is unaffordable to many locals. Funds may be allocated to local advertising campaigns to promote ostrich meat; provision of incentives to farmers; and improving the capacity of abattoirs.


Assuntos
Criação de Animais Domésticos/história , Struthioniformes/crescimento & desenvolvimento , Criação de Animais Domésticos/economia , Animais , Egito , Plumas , Feminino , História do Século XX , História do Século XXI , História Antiga , Masculino , Carne
6.
Br Poult Sci ; 49(1): 1-6, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18210283

RESUMO

1. The incidence of spread bow leg syndrome and associated pathology in 15 ostrich chicks aged 2, 4, 8 and 12 weeks is reported. Measurements were made of hind limbs: femur plus tibiotarsus; tarsometatarus; phalanx I, digit III; phalanx II, digit III plus phalanx III, digit III; and phalanx IV, digit III. 2. A run was constructed (6 m x 1.7 m) and subdivided into 2 m sections and the time taken to traverse it was recorded. Measurements (cm) were made of the left and right footprints; the number of footprints and average stride length in 0 to 2, 3 to 4 and 5 to 6 m. Speed was calculated using distance run (m) divided by time taken (s). 3. The number of steps was greater in bow leg chicks aged 4 and 8 weeks by comparison with healthy birds. Stride length, however, was smaller in all age groups with bow leg. All speeds in bow leg chicks were lower than those in healthy birds, except for that recorded at 2 m in chicks aged 2 weeks which did not differ markedly. 4. In affected birds, feathers were sparse. Icterus was present. The tarsometatarsus was twisted, with severely inflamed joints, eroded distal ends, thickening of the cartilage and the presence of fibrous material surrounding the ligaments. Muscles in the hind limb were emaciated. 5. The syndrome compromises the ability of chicks to keep up with adults in flocks, and may compromise their ability to escape predation.


Assuntos
Doenças das Aves/patologia , Struthioniformes , Envelhecimento , Animais , Membro Posterior/patologia , Locomoção , Síndrome
7.
Circulation ; 104(3): 325-9, 2001 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-11457752

RESUMO

BACKGROUND: Activation of the heart renin-angiotensin system (RAS) under pathophysiological conditions has been correlated with the development of ischemic injury. The binding of angiotensin II to its receptors triggers induction of several, perhaps multifunctional, intracellular signaling pathways, notable among them the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway. In this study, we investigated whether the JAK/STAT signaling is involved in the ischemia/reperfusion injury in adult rat myocardium. METHODS AND RESULTS: We report here that 2 components of the JAK/STAT signaling pathway, namely STAT 5A and STAT 6, are selectively activated in the rat heart subjected to ischemia/reperfusion. The activated STATs bind to a conserved nucleotide sequence (St domain) in the promoter of the angiotensinogen (ANG) gene and consequently upregulate the level of ANG mRNA. Treatment of the hearts with losartan (4.5 micromol/L), an AT(1) blocker, or with tyrphostin AG490 (5 micromol/L), an inhibitor of JAK 2 phosphorylation, results in loss of the STAT/ANG promoter binding activity and an upregulated level of ANG mRNA. Hearts treated with the JAK 2 inhibitor tyrphostin AG490 showed a reduction in myocardial infarct size and in number of cardiomyocytes undergoing apoptosis. The treated hearts also showed a recovery in functional hemodynamics of the myocardium. CONCLUSIONS: These findings suggest that activation of the JAK/STAT signaling pathway is a significant contributing factor to the pathogenesis of myocardial ischemia and that interference in activation of the pathway potentiates recovery in cardiac function.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Proteínas do Leite , Isquemia Miocárdica/fisiopatologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas , Transdução de Sinais , Transativadores/metabolismo , Angiotensinogênio/genética , Angiotensinogênio/metabolismo , Animais , Inibidores Enzimáticos/farmacologia , Técnicas In Vitro , Janus Quinase 2 , Masculino , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/metabolismo , Fosforilação/efeitos dos fármacos , Regiões Promotoras Genéticas , Proteínas Tirosina Quinases/antagonistas & inibidores , RNA Mensageiro/metabolismo , Ratos , Fator de Transcrição STAT5 , Fator de Transcrição STAT6 , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Tirfostinas/farmacologia , Regulação para Cima
8.
Int J Gynaecol Obstet ; 50 Suppl 2: S109-S111, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29645161

RESUMO

To identify causes of maternal death in Egypt and with that knowledge to effect its reduction, the Ministry of Health launched a study, a unique aspect of which was exploration of avoidable factory at home, in medical facilities, and during transportation from one to the other. The country must make better use of existing personnel and buildings.

9.
J Egypt Soc Parasitol ; 23(2): 493-500, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8376866

RESUMO

To study the effect of chemotherapy on concomitant immunity, mice infected with Schistosoma mansoni were treated after either 8 or 16 weeks of primary infection and challnged at different periods after treatment. Results were compared with infected un-treated groups of mice. It was found that in mice treated 8 weeks after infection the degree of protection decreased gradually with time and 16 weeks after treatment no significant degree of protection was obtained. On the other hand, mice infected for 16 weeks prior to treatment showed higher degrees of protection and there was still significant degree of resistance to challenge infection after 16 weeks of treatment. It was concluded that in schistosomiasis mansoni there is a certain degree of resistance to reinfection after successful treatment of primary infection prior to treatment.


Assuntos
Praziquantel/uso terapêutico , Esquistossomose mansoni/imunologia , Animais , Imunidade Ativa , Camundongos , Recidiva , Esquistossomose mansoni/tratamento farmacológico , Fatores de Tempo
10.
J Egypt Public Health Assoc ; 67(3-4): 521-33, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1296977

RESUMO

The availability of nitrogen, lysine and nine essential amino acids was determined in rice flour and cooked rice. Lysine availability was determined by the growth response method using regression analysis of body weight gain or moisture gain against lysine consumed from rice flour and cooked rice. The results show a good correlation between lysine consumed and weight gain or moisture gain (r = 0.86 + 0.8) for rats fed cooked rice and fair correlation for those fed rice flour. The results of lysine availability show that cooking increases availability by both ways of calculation. The availability of nitrogen and of essential amino acids was also determined by the balance trial method with rats. Results of balance trial show that cooking has no significant effect on essential amino acids availability. Data for weight gain, food efficiency and PER were significantly decreased by cooking.


Assuntos
Aminoácidos Essenciais/análise , Culinária , Farinha/análise , Oryza/química , Animais , Valor Nutritivo , Ratos
11.
Nahrung ; 32(9): 867-73, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3244379

RESUMO

The gross chemical composition, protein content and amino acid composition of mango stone kernels of four Egyptian varieties (Ewsi, Hendi, Fonso and Timour) were investigated. Carbohydrates are the main components of the seed. The protein content varies between 5.0 and 7.2% and the ether extract ranged from 10.8% to 13.6%. High glutamic acid, aspartic acid and leucine content and low concentration of sulfur-containing amino acids are characteristic for the proteins of mango kernels. Lysine level is also low, the concentration of other essential amino acids is acceptable. Sulfur-containing amino acids are the first limiting ones followed by lysine and threonine.


Assuntos
Frutas/análise , Proteínas de Plantas/análise , Aminoácidos/análise , Aminoácidos Essenciais/análise , Minerais/análise
12.
Nahrung ; 32(6): 553-7, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3231248

RESUMO

Five different brands of instant dry whole milk that are most commonly used, and freeze dried milk were analyzed for nitrogen, fat, ash and 4 inorganic constituents and compared with human milk. The composition of the milks differed considerably. The protein content varied widely, ranging from 11.6 to 24.5%. Fat content did not differ widely, ranging from 24.9 to 29.5%. Freeze dried milk had the highest fat content (42.6%). Three out of the five brands of dry milk studied were spray dried and the remaining two were roller dried. All milks tested contained considerably more sodium, potassium, calcium and phosphorus solid than human milk, some of them the four fold amount of calcium and phosphorus.


Assuntos
Manipulação de Alimentos , Leite/análise , Animais , Bovinos , Gorduras na Dieta/análise , Liofilização , Proteínas do Leite/análise , Minerais/análise , Valor Nutritivo
13.
Nahrung ; 32(6): 559-64, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3231249

RESUMO

Five different brands of dry milk and freeze dried milk were used in rat feeding trials to study their nutritive value and to assess the effect of the drying process on their nutritive value by using growth response, weight gain, food efficiency and relative nutritive value (RNV). Brand I milk gave better growth response, weight gain and food efficiency than any other dry milk studied, while brand V gave the least values. Freeze dried milk gave better growth response, weight gain and food efficiency than brand I milk. Using Slope-ratio assay, freeze dried milk gave the best RNV compared to all dry milks tested on the basis of the two response parameters used, weight gain and moisture gain.


Assuntos
Manipulação de Alimentos , Leite/análise , Animais , Peso Corporal/efeitos dos fármacos , Dieta , Proteínas Alimentares/metabolismo , Feminino , Liofilização , Crescimento/efeitos dos fármacos , Masculino , Nitrogênio/metabolismo , Valor Nutritivo , Ratos
14.
Nahrung ; 32(8): 729-35, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3231259

RESUMO

The protein value of meat soy blend was evaluated by utilizing the net protein ratio (NPR), the relative protein value (RPV) and the serum urea content methods. It was compared with that of meat. Casein was used as a reference protein. NPR values indicated that utilization of meat and meat soy proteins are comparable. The study of amino acid pattern shows that sulphur containing amino acids are limiting to almost the same degree in meat and meat soy blend. However, the RPV of meat soy bean blend is slightly higher than that of meat. The lowest serum urea content was that of rats fed meat soy blend. Therefore, the mixing of meat with soy bean did not reduce the nutritive value of meat, on the contrary there is tendency towards improvement.


Assuntos
Glycine max/análise , Carne/análise , Aminoácidos/análise , Animais , Peso Corporal/efeitos dos fármacos , Caseínas/análise , Dieta , Proteínas Alimentares/análise , Egito , Nitrogênio/análise , Valor Nutritivo , Ratos , Fatores de Tempo
16.
Nahrung ; 27(8): 803-8, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6633636

RESUMO

The availability of nitrogen, lysine and 9 essential amino acids was determined in corn before and after baking. Lysine availability was determined by the growth response method on weaning rats using regression analysis of body weight gain or moisture gain against lysine consumed from corn flour and corn bread. The results show a high correlation between lysine consumed and weight gain or moisture gain (r = 0.95) for rats fed the standard diets for 3 weeks. A good correlation was also obtained for corn bread. The results of lysine availability show that baking greatly improves availability by both ways of calculation. The availability of nitrogen and essential amino acids were also investigated by the balance trials with rats. Results show that availability values for nitrogen and all amino acids except threonine increased by baking. Data for food intake, weight gain, food efficiency, PER, NPR and true digestibility revealed that baking had little or no effect on nutritive value of corn tested in this investigation.


Assuntos
Aminoácidos Essenciais/metabolismo , Proteínas Alimentares/metabolismo , Zea mays/análise , Aminoácidos/análise , Animais , Pão/análise , Proteínas Alimentares/normas , Digestão , Farinha/análise , Crescimento , Valor Nutritivo , Ratos
17.
Nahrung ; 27(1): 45-53, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6406895

RESUMO

Lysine availability in wheat flour and bread was determined by the growth response method on rats using regression analysis relating gain in body weight and/or in body water to lysine consumed at two extractions, 87% and 72%. The availability of nitrogen and of essential amino acids were also determined by the balance trials method (fecal analysis method) with rats. The results of growth method show that baking increases lysine availability on the basis of body water gain. Also extraction levels affect lysine availability on the basis of change in body water. Wheat flour and bread of 72% extraction has more lysine availability values than the 87% extraction on the basis of moisture gain. Results of balance trials show that neither the extraction level nor the baking has a significant effect on essential amino acids availability. A fairly good correlation is obtained for wheat flour and bread for the two extractions. Values of change in weight, food efficiency, PER, NPR and true digestibility showed that baking and level of extraction of wheat has no significant effect on the nutritive value of wheat investigated in the present study.


Assuntos
Aminoácidos Essenciais/metabolismo , Triticum/análise , Animais , Peso Corporal , Pão , Culinária , Digestão , Feminino , Farinha/análise , Lisina/metabolismo , Masculino , Nitrogênio/metabolismo , Valor Nutritivo , Proteínas de Plantas/metabolismo , Ratos
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