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1.
Sci Rep ; 13(1): 14788, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37684309

RESUMO

The essential purpose of this study is to discuss the impact of time-periodic variations on mixed convection heat transfer for MHD Eyring-Powell nanofluid. The fluid flows through a non-Darcy porous medium over an infinite vertical plate. The effects of viscous dissipation, Ohmic dissipation, electro-osmosis force, heat source, thermal radiation, Dufour feature, and chemical reaction are presumed. The system of partial differential equations which governs the problem is transformed into a system of non-linear algebraic equations and then an explicit finite difference approach is espoused to solve these nonlinear algebraic equations. The numerical results for the velocity, temperature, and nanoparticles concentration distributions are computed and displayed through a set of graphs. Also, the skin friction coefficient, reduced Nusselt number, and Sherwood number are computed numerically for various values of the physical parameters. It is found that the velocity becomes greater with an elevation in the value of the Helmholtz-Smoluchowski velocity. Meanwhile, it enlarges with rising in the value of the electro-osmotic parameter. The rise in the value of the thermal radiation parameter causes a dwindling influence on both temperature and nanoparticles concentration. Investigations of these effects together are very useful due to their important vital applications in various scientific fields, especially in medicine and medical industries, such as endoscopes, respirators, and diverse medical implementations, as nanoparticles can be utilized in the remedy of cancer tumors. Additionally, electroosmotic flow is important due to its ability to control fluid movement and enhance mass transport, making it valuable in various application such as sample separation, drug delivery, and DNA analysis, offering enhanced efficiency and sensitivity.

2.
Sci Rep ; 13(1): 9191, 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37280357

RESUMO

This study aimed to give a new theoretical recommendation for non-dimensional parameters depending on the fluid temperature and concentration. This suggestion came from the fact of fluid density may change with the fluid temperature ([Formula: see text]) and concentration ([Formula: see text]). So, a newly released mathematical form of Jeffrey fluid with peristalsis through the inclined channel is constructed. The problem model defines a mathematical fluid model which converts using non-dimensional values. A sequentially used technique called the Adaptive shooting method for finding the problem solutions. Axial velocity behavior has become a novel concern to Reynolds number. In contradiction to different values of parameters, the temperature and concentration profiles are designated/sketched. The results show that the high value of the Reynolds number acts as a fluid temperature damper, while it boosts the concentration of the fluid particle. The non-constant fluid density recommendation makes the Darcy number controls with a fluid velocity which is virtually significant in drug carries applications or blood circulation systems. To verify the obtained results, a numerical comparison for obtained results has been made with a trustful algorithm with aid of AST using wolfram Mathematica version 13.1.1.

3.
Sci Rep ; 12(1): 18747, 2022 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-36335139

RESUMO

This study is carried out to analyze the problem of mixed convection magnet nanoflow of Prandtl fluid through a non-uniform channel with peristalsis. The external influences of activation energy and non-constant velocity slip are given full consideration. The mentioned fluid is expressed as a governing equations system, and then these equations are converted with non-dimensional parameter values to a system of ordinary differential equations. The converted system of equations is solved in terms of y and then graphs and sketches are offered using the generalized differential transform method. Graphs and results for volume friction as well as velocity profile, concentration, and temperature distributions are obtained. Results show development in the velocity profile of fluid distribution through high values of the non-constant velocity slip effect. The present study is alleged to deliver more opportunities to advance the applications of the drug-carrying system in hypoxic tumor areas with aid of identifying the flow mechanisms.


Assuntos
Temperatura Alta , Peristaltismo , Convecção , Temperatura , Fricção
4.
Braz. j. microbiol ; 42(3): 1007-1016, July-Sept. 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-607531

RESUMO

This study was conducted to evaluate the effect of aqueous, ethanolic and ethyl acetate extracts from neem leaves on growth of some human pathogens (Aspergillus flavus, Aspergillus fumigatus, Aspergillus niger, Aspergillus terreus, Candida albicans and Microsporum gypseum) in vitro. Different concentrations (5, 10, 15 and 20 percent) prepared from these extracts inhibited the growth of the test pathogens and the effect gradually increased with concentration. The 20 percent ethyl acetate extract gave the strongest inhibition compared with the activity obtained by the same concentration of the other extracts. High Performance Liquid Chromatography (HPLC) analysis of ethyl acetate extract showed the presence of a main component (nimonol) which was purified and chemically confirmed by Nuclear Magnetic Resonance (NMR) spectroscopic analysis. The 20 percent ethyl acetate extract lost a part of its antifungal effect after pooling out the nimonol and this loss in activity was variable on test pathogens. The purified nimonol as a separate compound did not show any antifungal activity when assayed against all the six fungal pathogens.


Assuntos
Humanos , Antifúngicos/análise , Azadirachta/genética , Fungos/genética , Técnicas In Vitro , Estruturas Vegetais , Cromatografia Líquida de Alta Pressão/métodos , Estruturas Vegetais/genética , Espectroscopia de Ressonância Magnética , Métodos , Métodos
5.
Braz J Microbiol ; 42(3): 1007-16, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24031718

RESUMO

This study was conducted to evaluate the effect of aqueous, ethanolic and ethyl acetate extracts from neem leaves on growth of some human pathogens (Aspergillus flavus, Aspergillus fumigatus, Aspergillus niger, Aspergillus terreus, Candida albicans and Microsporum gypseum) in vitro. Different concentrations (5, 10, 15 and 20%) prepared from these extracts inhibited the growth of the test pathogens and the effect gradually increased with concentration. The 20% ethyl acetate extract gave the strongest inhibition compared with the activity obtained by the same concentration of the other extracts. High Performance Liquid Chromatography (HPLC) analysis of ethyl acetate extract showed the presence of a main component (nimonol) which was purified and chemically confirmed by Nuclear Magnetic Resonance (NMR) spectroscopic analysis. The 20% ethyl acetate extract lost a part of its antifungal effect after pooling out the nimonol and this loss in activity was variable on test pathogens. The purified nimonol as a separate compound did not show any antifungal activity when assayed against all the six fungal pathogens.

6.
East Mediterr Health J ; 13(6): 1405-16, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18341190

RESUMO

We conducted a cross-sectional study on a randomly selected sample of 2304 males aged 15-49 years from 4 governorates in Lower Egypt to assess their condom use and knowledge and attitudes towards condom use. Condoms were considered an effective method of contraception and prevention of transmission of sexually transmitted infections (STIs) by 60.5% and 60.0% respectively. Only 23.9% had ever used condoms, mainly for contraception, but 26.8% would consider using them in the future. A quarter reported knowing how to use condoms properly. Obstacles to condom use included perceived lack of need (75.7%), rejection by partner (57.6%) and hazards of condoms (31.9%). The majority knew about HIV/AIDS (90.8%) but a few felt at risk of STIs (11.2%) or HIV infection (10.3%).


Assuntos
Atitude Frente a Saúde , Preservativos/estatística & dados numéricos , Comportamento Contraceptivo , Conhecimentos, Atitudes e Prática em Saúde , Homens/psicologia , Sexo Seguro , Adolescente , Adulto , Atitude Frente a Saúde/etnologia , Distribuição de Qui-Quadrado , Anticoncepção/métodos , Anticoncepção/psicologia , Anticoncepção/estatística & dados numéricos , Comportamento Contraceptivo/etnologia , Comportamento Contraceptivo/estatística & dados numéricos , Estudos Transversais , Egito/epidemiologia , Serviços de Planejamento Familiar , Necessidades e Demandas de Serviços de Saúde , Humanos , Masculino , Estado Civil/estatística & dados numéricos , Homens/educação , Pessoa de Meia-Idade , Motivação , Ocupações/estatística & dados numéricos , Características de Residência/estatística & dados numéricos , Assunção de Riscos , Sexo Seguro/etnologia , Sexo Seguro/estatística & dados numéricos , Parceiros Sexuais/psicologia , Infecções Sexualmente Transmissíveis/etnologia , Infecções Sexualmente Transmissíveis/prevenção & controle , Inquéritos e Questionários
7.
(East. Mediterr. health j).
em Inglês | WHO IRIS | ID: who-117391

RESUMO

We conducted a cross-sectional study on a randomly selected sample of 2304 males aged 15-49 years from 4 governorates in Lower Egypt to assess their condom use and knowledge and attitudes towards condom use. Condoms were considered an effective method of contraception and prevention of transmission of sexually transmitted infections [STIs] by 60.5% and 60.0% respectively. Only 23.9% had ever used condoms, mainly for contraception, but 26.8% would consider using them in the future. A quarter reported knowing how to use condoms properly. Obstacles to condom use included perceived lack of need [75.7%], rejection by partner [57.6%] and hazards of condoms [31.9%]. The majority knew about HIV/AIDS [90.8%] but a few felt at risk of STIs [11.2%] or HIV infection [10.3%]


Assuntos
Atitude Frente a Saúde , Comportamento Contraceptivo , Estudos Transversais , Conhecimentos, Atitudes e Prática em Saúde , Homens , Sexo Seguro , Infecções Sexualmente Transmissíveis , Inquéritos e Questionários , Preservativos
8.
Hepatogastroenterology ; 47(33): 663-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10919007

RESUMO

BACKGROUND/AIMS: Hepatocellular carcinoma is one of the commonest malignancies in the world. The two main etiological factors for hepatocellular carcinoma are cirrhosis and viral hepatitis. Although the first choice of treatment for hepatocellular carcinoma is surgical resection, most of them are unresectable at the time of diagnosis. METHODOLOGY: From January 1994 to June 1999, 385 patients with hepatocellular carcinoma were presented to the Gastroenterology surgical center, Mansoura University, Egypt and subjected to similar diagnostic process. Forty-five (11.6%) of these patients (34 males and 13 females) with a mean age of 50.9 years (+/- 7.53 years) were subjected to different types of hepatic resection. RESULTS: The underlying liver pathology was cirrhosis in 85%. Positive virology was found in 82.5% (HCV 61%, HBV 14.5% and combined 7%). The main presentation were asymptomatic in 144 (37.4%) patients, abdominal pain in 92 (23.9%) patients, ascites in 95 (24.6%) patients, jaundice in 53 (14%) patients and upper gastrointestinal hemorrhage in 26 (6.75%) patients. Only 45 (11.6%) were resectable, they were subjected to hepatic resection with operative mortality in 2 cases (4.4%) and with overall mortality in 29 (64.4%) cases after 48 months (32.8 +/- 19 months) of follow-up. The main causes of late mortality were recurrence in 14 (31.1%) cases, hepatic cell failure in 7 (15.5%) cases and other causes in 6 (13.3%). CONCLUSIONS: Hepatocellular carcinoma is now a common malignancy in Egypt, which usually develops on top of cirrhosis of viral origin in 82%. Hepatic resection is the only method of treatment with a low resectability rate.


Assuntos
Carcinoma Hepatocelular/cirurgia , Hepatectomia , Neoplasias Hepáticas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/mortalidade , Egito , Feminino , Humanos , Cirrose Hepática/complicações , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida
9.
J Environ Sci Health B ; 29(2): 303-21, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8169318

RESUMO

Human serum transferrin (HSTF), human serum albumin (HSA) and rat serum were compared for their interaction with AlCl3, in a Tris-HCl buffer solutions (pH 7.4). The AlCl3 was tested in series of concentrations in the range of 50 microM up to 500 microM. HSTF, HSA and their 1:1 mixture and rat serum were incubated at 37 degrees C with series of AlCl3 concentrations. The protein profile of the incubated solutions were compared to control using SDS-PAGE and FPLC tests. The results indicated that HSTF was more specifically responsive to AlCl3 showing a characteristic increase in its UV absorption, peak and area dimensions. Simultaneously, HSA was less affected, but it showed a significant shift with an increase in molecular weight accompanied with a change in its profile. The respective bands of transferrin and albumin in rat serum behaved similarly. The SDS-PAGE and FPLC data coincided and confirmed the preferential affinity of HSTF to bind with Al3+. These results support the suggestion of using HSTF for monitoring levels of Al3+ in human blood samples of exposed population. The importance of further developing such a biomarker is the increased demand for early detection of the hazardous levels of Al3+ in relation to its long term neurotoxic adverse effects.


Assuntos
Compostos de Alumínio/sangue , Proteínas Sanguíneas/metabolismo , Cloretos/sangue , Exposição Ambiental , Albumina Sérica/metabolismo , Transferrina/metabolismo , Cloreto de Alumínio , Animais , Biomarcadores/sangue , Cromatografia Líquida , Eletroforese em Gel de Poliacrilamida , Humanos , Focalização Isoelétrica , Ligação Proteica , Ratos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrofotometria Ultravioleta
10.
J Chem Ecol ; 20(1): 135-40, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24241704

RESUMO

Calotropis procera, is a shrub with broad ovate fleshy leaves that grows wild in the Egyptian deserts. The plant was discovered to be highly toxic to the land snailsThepa pisana. The active ingredient responsible for the molluscicidal activity was isolated from its latex by solvent extraction and partitioning and was finally purified by fractional crystallization from 95% aqueous ethanol. The purity of the isolated material was monitored by TLC. Chemical identification was carried out using mass, infrared, and proton magnetic resonance spectroscopic methods. The active compound was found to be uscharin, and its identity was confirmed by comparing its spectroscopic data with the literature values. The isolated compound was 128 times more toxic than methomyl to the snails tested.

11.
J Environ Sci Health B ; 28(6): 763-77, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8270765

RESUMO

Phosphorylation is an indispensable process for energy and signal transduction in biological systems. AlCl3 at 10 nM to 10 microM range activated in-vitro [gamma-32P]ATP phosphorylation of the brain (tau) tau protein in both normal human or E. coli expressed tau forms; in the presence of the kinases P34, PKP, and PKC. However, higher concentrations of ALCl3 inhibited the tau phosphorylation with P34, PKP, and PKC to a maximum at 1 mM level. AlCl3 at 100 microM to 500 microM range induced non-enzymatic phosphorylation of tau with gamma-ATP, gamma-GTP, and alpha-GTP. AlCl3 activated histone phosphorylation by P34 in a similar pattern. The hyperphosphorylation of tau by Al3+ was accompanied by molecular shift and mobility retardation in SDS-PAGE. This may demonstrate the mechanism of the longterm neurological effect of Al3+ in human brain leading to the formation of the neurofibrillary tangles related to Alzheimer's disease.


Assuntos
Compostos de Alumínio/toxicidade , Encéfalo/efeitos dos fármacos , Cloretos/toxicidade , Fosfotransferases/farmacologia , Proteínas tau/metabolismo , Trifosfato de Adenosina/metabolismo , Cloreto de Alumínio , Encéfalo/metabolismo , Proteína Quinase CDC2/farmacologia , Densitometria , Relação Dose-Resposta a Droga , Eletroforese em Gel de Poliacrilamida , Escherichia coli , Guanosina Trifosfato/metabolismo , Histonas/metabolismo , Humanos , Técnicas In Vitro , Fosforilação , Proteína Quinase C/farmacologia , Proteínas Serina-Treonina Quinases/farmacologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas tau/genética
12.
J Environ Sci Health B ; 28(4): 413-30, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8335887

RESUMO

14C-methoxy-malathion with either pure or 50% E.C. formulated malathion were applied orally or dermally at one tenth of their LD50 to two batches of male albino rats. More than 90% of 14C was released with urine after 24 hours. The rest of 14C was detected in the feces, blood, intestines, liver and kidney in a descending order. No significant 14C was detected in other organs. Comparing the oral pure and formulated malathion treatments, there was no significant variation in the rate of disposition or excretion of 14C-malathion. However, the dermal treatment revealed that the 14C-formulated malathion was released faster than the pure one in urine in the first 24 hours; while the 14C-pure malathion showed relatively higher levels in the feces and blood in the first 24 hours. In a third batch of male albino rats, the effect of the same level of dermal treatment by either pure or 50% E.C. formulated malathion on serum acetylcholine-esterase (A. Ch. E.) activity and serum protein profile was studied. The serum A. Ch. E. activity was found to be inhibited to 40% activity after 6 to 24 hours for both treatments. However, after 96 hours the serum of the pure malathion treated rats showed full recovery of A.Ch.E. activity, while the formulated malathion treated showed only 60% activity. The SDS-PAGE analysis showed a differentiation in the serum protein bands of the 48 hours exposed rats to formulated malathion which was confirmed by the scanned gel profile. The FPLC integrated chromatograms proved an initiation of a new protein band accompanied with rearrangement of the albumin and pre-albumin bands. Thus it can be concluded that, the impact on the blood serum protein profile and A. Ch. E. activity can be used as reliable criteria to detect acute toxicity of malathion and other choline-esterase inhibitors in exposed field workers. Further research is needed to elucidate the specificity and sensitivity of such criteria as biomarkers for human exposure.


Assuntos
Acetilcolinesterase/efeitos dos fármacos , Malation/farmacocinética , Albumina Sérica/efeitos dos fármacos , Acetilcolinesterase/sangue , Administração Cutânea , Administração Oral , Animais , Fezes/química , Malation/administração & dosagem , Malation/análise , Malation/sangue , Malation/toxicidade , Malation/urina , Masculino , Ratos , Distribuição Tecidual
13.
J Egypt Public Health Assoc ; 67(5-6): 685-95, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1294689

RESUMO

Serum samples were collected from 40 patients with enlarged lymph nodes. Lymph node and bone marrow biopsies were performed and processed as usual. Tumor necrosis factor-alpha (TNF alpha) was determined in the sera by factor test human TNF alpha ELISA kit. Histopathological studies of lymph node and bone marrow biopsies were evaluated. The data obtained from this study showed that bone marrow was involved in only 5 patients and their TNF showed the lowest level in this study with a mean level 50 pg/ml. The highest level of TNF occurred in cases with granulomatous lymphadenitis (124 pg/ml) followed by reactive lymphadenitis (105 pg/ml). It can be considered that TNF reflects the immune status of the patient and its study in the serum can be of help in evaluating the progress of the disease. An extended study is need to evaluate the role of TNF-alpha as a prognostic marker in malignancy.


Assuntos
Doenças Linfáticas/sangue , Fator de Necrose Tumoral alfa/química , Adolescente , Biópsia , Exame de Medula Óssea , Feminino , Humanos , Excisão de Linfonodo , Doenças Linfáticas/etiologia , Doenças Linfáticas/patologia , Masculino
14.
Nephron ; 39(2): 86-94, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3156279

RESUMO

Elevated serum gastrin (SG) has been reported in chronic renal failure (CRF). We studied SG levels in relation to various humoral and gastroduodenal histopathologic findings in 20 controls, 12 uremics under conservative therapy (CT), 27 patients on regular dialysis (RDT) and 8 transplanted patients (Tx). SG and parathyroid hormone (PTH) levels were estimated by radioimmunoassay (RIA), in addition serum BUN, creatinine, Ca++PO4---and alkaline phosphatase (predialysis in RDT) were determined. 20 patients (12 on CT and 8 on RDT) underwent pentagastrin (PG) stimulation test and upper gastrointestinal endoscopy with biopsy of gastric and duodenal mucosa. The mucosal samples were stained for mucopolysaccharides (MPS), nucleic acid (NA) and alkaline phosphatase (AP), and divided into intense, normal or faint staining. Mean SG was 688.71 pg/ml (CT cases), 636.2 pg/ml (RDT cases) and 280.6 pg/ml (Tx cases), all values being significantly higher than controls (118.46 pg/ml). SG level had a linear correlation with serum creatinine in CT patients and predialysis creatinine in RDT patients, but not with other parameters studied (BUN, Ca++,PTH,PO4---AP). The incidence of gastroduodenal erosions (40%) had a significant negative correlation with SG. They were more frequent with normal MPS stain (p = 0.01) and NA staining (p less than 0.001) than faint staining of gastric mucosa biopsy. The acid response to PG stimulation was inversely correlated with SG. We believe that elevated SG is compensatory to a decreased response of the gastroduodenal mucosa to PG. Mere retention of SG does not explain its elevation as its correlation with serum creatinine existed not only in patients on CT, but also in RDT patients.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Mucosa Gástrica/patologia , Gastrinas/sangue , Falência Renal Crônica/sangue , Fosfatase Alcalina/análise , Feminino , Ácido Gástrico/metabolismo , Gastroscopia , Glicosaminoglicanos/análise , Histocitoquímica , Humanos , Falência Renal Crônica/patologia , Masculino , Ácidos Nucleicos/análise , Hormônio Paratireóideo/sangue
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