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1.
Sci Rep ; 12(1): 22269, 2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36564522

RESUMO

In this work, novel two-dimensional BC[Formula: see text]X (X = N, P, As) monolayers with X atoms out of the B-C plane, are predicted by means of the density functional theory. The structural, electronic, optical, photocatalytic and thermoelectric properties of the BC[Formula: see text]X monolayers have been investigated. Stability evaluation of the BC[Formula: see text]X single-layers is carried out by phonon dispersion, ab-initio molecular dynamics (AIMD) simulation, elastic stability, and cohesive energies study. The mechanical properties reveal all monolayers considered are stable and have brittle nature. The band structure calculations using the HSE06 functional reveal that the BC[Formula: see text]N, BC[Formula: see text]P and BC[Formula: see text]As are semiconducting monolayers with indirect bandgaps of 2.68 eV, 1.77 eV and 1.21 eV, respectively. The absorption spectra demonstrate large absorption coefficients of the BC[Formula: see text]X monolayers in the ultraviolet range of electromagnetic spectrum. Furthermore, we disclose the BC[Formula: see text]N and BC[Formula: see text]P monolayers are potentially good candidates for photocatalytic water splitting. The electrical conductivity of BC[Formula: see text]X is very small and slightly increases by raising the temperature. Electron doping may yield greater electric productivity of the studied monolayers than hole doping, as indicated by the larger power factor in the n-doped region compared to the p-type region. These results suggest that BC[Formula: see text]X (X = N, P, As) monolayers represent a new promising class of 2DMs for electronic, optical and energy conversion systems.

2.
Phys Chem Chem Phys ; 23(21): 12226-12232, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34009225

RESUMO

Pure hydrogen production via water splitting is an ideal strategy for producing clean and sustainable energy. Two-dimensional (2D) cadmium chalcogenide single-layers with a tetragonal crystal structure, namely Tetra-CdX (X = S, Se, and Te) monolayers, are theoretically predicted by means of density functional theory (DFT). Their structural stability and electronic and optical properties are investigated. We find that Tetra-CdX single-layers are thermodynamically stable. Their stability decreases as we go down the 6A group in the periodic table, i.e., from X = S to Se, and Te which also means that the electronegativity decreases. All considered novel monolayers are indirect band gap semiconductors. Using the HSE06 functional the electronic band gaps of CdS, CdSe, and CdTe monolayers are predicted to be 3.10 eV, 2.97 eV, and 2.90 eV, respectively. The impact of mechanical strain on the physical properties was studied, which indicates that compressive strain increases the band gap and tensile strain decreases the band gap. The optical properties of the Tetra-CdX monolayers show the ability of these monolayers to absorb visible light. Due to the suitable band gaps and band edge positions of Tetra-CdX, these newly discovered 2D materials are promising for photocatalytic water splitting.

3.
Phys Chem Chem Phys ; 22(27): 15354-15364, 2020 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-32589177

RESUMO

Nonmetal doping is an effective approach to modify the electronic band structure and enhance the photocatalytic performance of bismuth oxyhalides. Using density functional theory, we systematically examine the fundamental properties of single-layer BiOBr doped with boron (B) and phosphorus (P) atoms. The stability of the doped models is investigated based on the formation energies, where the substitutional doping is found to be energetically more stable under O-rich conditions than under Bi-rich ones. The results showed that substitutional doping of P atoms reduced the bandgap of pristine BiOBr to a greater extent than that of boron substitution. The calculation of the effective masses reveals that B doping can render the electrons and holes of pristine BiOBr lighter and heavier, respectively, resulting in a slower recombination rate of photoexcited electron-hole pairs. Based on the results of HOMO-LUMO calculations, the introduction of B atoms tends to increase the number of photocatalytically active sites. The top of the valence band and the conduction band bottom of the B doped BiOBr monolayer match well with the water redox potentials in an acidic environment. The absorption spectra propose that B(P) doping causes a red-shift. Overall, the results predict that nonmetal-doped BiOBr monolayers have a reduced bandgap, a slow recombination rate, more catalytically active sites, enhanced optical absorption edges, and reduced work functions, which will contribute to superior photocatalytic performance.

4.
Rev. esp. med. nucl. imagen mol. (Ed. impr.) ; 38(5): 275-279, sept.-oct. 2019. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-189254

RESUMO

OBJETIVO: La precisión diagnóstica de la imagen de perfusión miocárdica (IPM) no es óptima para predecir el resultado de la angiografía. El objetivo del presente estudio es investigar la aplicación de la red neuronal artificial (RNA) para integrar los datos clínicos con el resultado y la cuantificación de la IPM. MÉTODOS: De 923 pacientes con IPM, se reclutaron 93 que se sometieron a angiografía. Se recogieron los datos clínicos, incluidos los factores de riesgo cardíaco, y se registraron los resultados de la IPM y la angiografía coronaria. Se calculó la cuantificación de las gráficas polares IPM (es decir, los recuentos de 20 segmentos de cada una de las gráficas polares de esfuerzo y de reposo) y la puntuación de Gensini de las angiografías. La RNA fue diseñada integrando datos clínicos y de cuantificación para predecir el resultado de la angiografía (normal vs. anormal), la enfermedad coronaria no obstructiva u obstructiva (EAC) y la puntuación de Gensini (≥10 y <10). Las RNA fueron diseñadas para predecir los resultados de la angiografía usando diferentes combinaciones de datos como sigue: informes de IPM, la cuantificación de 40 segmentos de diagramas polares de esfuerzo y reposo, y la cuantificación de estos 40 segmentos además de la edad, el sexo y el número de factores de riesgo. Se comparó el rendimiento diagnóstico de la IPM con diferentes RNA. RESULTADOS: La precisión de la IPM para predecir el resultado de la angiografía, la EAC obstructiva y la puntuación de Gensini aumentó del 81,7 al 92,9%, del 65,0 al 85,7% y del 50,5 al 92,9%, respectivamente, mediante la RNA con cuantificación y factores de riesgo clínicos. CONCLUSIÓN: La precisión diagnóstica de la IPM podría mejorarse mediante la RNA, utilizando datos clínicos y de cuantificación


OBJECTIVE: Diagnostic accuracy of myocardial perfusion imaging (MPI) is not optimal to predict the result of angiography. The current study aimed at investigating the application of artificial neural network (ANN) to integrate the clinical data with the result and quantification of MPI. METHODS: Out of 923 patients with MPI, 93 who underwent angiography were recruited. The clinical data including the cardiac risk factors were collected and the results of MPI and coronary angiography were recorded. The quantification of MPI polar plots (i. e. the counts of 20 segments of each stress and rest polar plots) and the Gensini score of angiographies were calculated. Feed-forward ANN was designed integrating clinical and quantification data to predict the result of angiography (normal vs. abnormal), non-obstructive or obstructive coronary artery disease (CAD), and Gensini score (≥10 and <10). The ANNs were designed to predict the results of angiography using different combinations of data as follows: reports of MPI, the counts of 40 segments of stress and rest polar plots, and the count of these 40 segments in addition to age, gender, and the number of risk factors. The diagnostic performance of MPI with different ANNs was compared. RESULTS: The accuracy of MPI to predict the result of angiography, obstructive CAD, and Gensini score increased from 81.7% to 92.9%, 65.0% to 85.7%, and 50.5% to 92.9%, respectively by ANN using counts and clinical risk factors. CONCLUSION: The diagnostic accuracy of MPI could be improved by ANN, using clinical and quantification data


Assuntos
Humanos , Masculino , Feminino , Angiografia Coronária/métodos , Imagem de Perfusão do Miocárdio/métodos , Redes Neurais de Computação , Doença da Artéria Coronariana/diagnóstico por imagem , Reprodutibilidade dos Testes , Estudos Retrospectivos
5.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31402311

RESUMO

OBJECTIVE: Diagnostic accuracy of myocardial perfusion imaging (MPI) is not optimal to predict the result of angiography. The current study aimed at investigating the application of artificial neural network (ANN) to integrate the clinical data with the result and quantification of MPI. METHODS: Out of 923 patients with MPI, 93 who underwent angiography were recruited. The clinical data including the cardiac risk factors were collected and the results of MPI and coronary angiography were recorded. The quantification of MPI polar plots (i.e. the counts of 20 segments of each stress and rest polar plots) and the Gensini score of angiographies were calculated. Feed-forward ANN was designed integrating clinical and quantification data to predict the result of angiography (normal vs. abnormal), non-obstructive or obstructive coronary artery disease (CAD), and Gensini score (≥10 and <10). The ANNs were designed to predict the results of angiography using different combinations of data as follows: reports of MPI, the counts of 40 segments of stress and rest polar plots, and the count of these 40 segments in addition to age, gender, and the number of risk factors. The diagnostic performance of MPI with different ANNs was compared. RESULTS: The accuracy of MPI to predict the result of angiography, obstructive CAD, and Gensini score increased from 81.7% to 92.9%, 65.0% to 85.7%, and 50.5% to 92.9%, respectively by ANN using counts and clinical risk factors. CONCLUSION: The diagnostic accuracy of MPI could be improved by ANN, using clinical and quantification data.


Assuntos
Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Imagem de Perfusão do Miocárdio/métodos , Redes Neurais de Computação , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Estudos Retrospectivos
6.
Anal Bioanal Chem ; 411(29): 7681-7688, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31286178

RESUMO

A new electrochemical sensor, based on NdFeO3 nanoparticles as electrocatalytic material, was proposed here for the detection of dopamine (DA). NdFeO3 nanoparticles were first synthesized by a simple thermal treatment method and subsequent annealing at high temperature (700 °C). The prepared electrocatalytic material has been characterized in detail by SEM-EDX, XRD, and Raman techniques. Characterization results display its sheet-like morphology, constituted by a porous network of very small orthorhombic NdFeO3 nanoparticles. NdFeO3 electrocatalytic material was then used to modify the working electrode of screen-printed carbon electrodes (SPCEs). Electrochemical tests demonstrated that NdFeO3- modified screen-printed carbon electrode (NdFeO3/SPCE) exhibited a remarkable enhancement of the dopamine electrooxidation, compared to the bare SPCE one. The analytical performance of the developed sensor has been evaluated for the detection of this analyte by means of the square-wave voltammetry (SWV) technique. The modified electrode showed two linear concentration ranges, from 0.5 to 100 µM and 150 to 400 µM, respectively, a limit of detection (LOD) of 0.27 µM (at S/N = 3), and good reproducibility, stability, and selectivity. Additionally, we also report an attempt made to propose the modified sensor for the simultaneous detection of dopamine and uric acid (UA). The procedure was also applied for the determination of dopamine in spiked real samples. So, this paper reports for the first time the use of a modified NdFeO3 screen-printed electrode for developing an electrochemical sensor for the quantification of important biomolecules. Graphical abstract.


Assuntos
Dopamina/análise , Técnicas Eletroquímicas/instrumentação , Compostos Férricos/química , Neodímio/química , Técnicas Biossensoriais , Catálise , Eletrodos , Humanos , Limite de Detecção , Reprodutibilidade dos Testes , Ácido Úrico/análise
7.
Neurogastroenterol Motil ; 30(10): e13273, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29286194

RESUMO

BACKGROUND: The inhibitory effects of H2 S on spontaneous contractions of smooth muscles of small, and large intestines well-established but its role in the pathophysiology of diarrhea has not been identified. Therefore, this study evaluated the role of exogenous H2 S (NaHS) on diabetic-induced diarrhea and determined mRNA expression of cystathionine ß-lyase (CSE) and cystathionine γ-synthase (CBS) in diabetic rats. METHODS: In order to evaluate antidiarrheal effect of H2 S, normal and diabetic rats received NaHS and L-Cysteine and the total number of fecal pellets (FP) determined. The effect of NaHS on intestinal transit ratio (ITR) was also evaluated in diabetic rats. The level of mRNA expressions of CBS and CSE determined in smooth muscles of jejunum, ileum, and colon in normal, and diabetic rats. The effect of NaHS on frequency and tension of spontaneous contractions of smooth muscle strips of colon, ileum, and jejunum were investigated. KEY RESULTS: NaHS decreased ITR, total number of FP, frequency and tension of spontaneous contractions of colon, ileum, and jejunum muscle strips in diabetic rats. The level of mRNA expression of CSE and CBS in diabetic rats were lower than in normal rats. NaHS, and L-Cysteine decreased the number of FP in normal rats. CONCLUSIONS & INFERENCES: These findings showed NaHS effectively controlled diarrhea in diabetic rats through decreasing the frequency, and tension of spontaneous contraction of smooth muscles of large, and small intestines. The increased frequency and tension of spontaneous contractions of smooth muscles in diabetic rats may be due to down-regulation of H2 S biosynthesis enzymes.


Assuntos
Diabetes Mellitus Experimental/fisiopatologia , Diarreia/fisiopatologia , Intestinos/efeitos dos fármacos , Sulfetos/farmacologia , Animais , Carbono-Oxigênio Liases/biossíntese , Carbono-Oxigênio Liases/efeitos dos fármacos , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/metabolismo , Diarreia/etiologia , Diarreia/metabolismo , Motilidade Gastrointestinal/efeitos dos fármacos , Motilidade Gastrointestinal/fisiologia , Intestinos/fisiopatologia , Liases/biossíntese , Liases/efeitos dos fármacos , Masculino , Contração Muscular/efeitos dos fármacos , Contração Muscular/fisiologia , Músculo Liso/efeitos dos fármacos , Músculo Liso/metabolismo , Músculo Liso/fisiopatologia , Ratos , Ratos Wistar
8.
Neurogastroenterol Motil ; 28(11): 1677-1689, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27324218

RESUMO

BACKGROUND: This study aimed to evaluate the role of H2 S on gastric emptying rate (GER) and also to determine the effect of gastric distention on mRNA and protein expression of cystathionine ß-lyase (CBS) and cystathionine γ-synthase (CSE) in diabetic-gastroparetic and normal rats. METHODS: Adult normal rats intraperitoneally received either propargylglycine (PAG), L-cysteine or NaHS 30 min prior to GER marker (acetaminophen) to investigate H2 S involvement in GER and the same protocols were performed in diabetes-induced gastroparesis rats. The role of calcitonin gene related peptide (CGRP) neurons in the prokinetic effect of endogenous H2 S on GER was determined. The level of CBS and CSE expressions in response to gastric distention were also determined. The effect of H2 S on frequency and tension of spontaneous contractions of gastric smooth muscle strips was investigated. KEY RESULTS: Our results showed that: (i) H2 S and L-cysteine increased GER in gastroparetic and normal rats. (ii) The increased levels of CSE expression in response to gastric distention in diabetic rats were lower than in normal rats. (iii) PAG inhibited the excitatory effect of capsaicin on GER and on tension of spontaneous contractions of strips. (iv) Hydrogen sulphide increased the frequency and tension of spontaneous contractions of gastric strip muscles in normal and diabetic rats. CONCLUSIONS & INFERENCES: The results showed that delayed GER in diabetic rats can be due to down-regulation of H2 S biosynthesis enzyme, CSE and suggested that a potential prokinetic role for H2 S to treat the delayed gastric emptying in diabetic patients.


Assuntos
Cistationina gama-Liase/biossíntese , Diabetes Mellitus Experimental/metabolismo , Esvaziamento Gástrico/fisiologia , Gastroparesia/metabolismo , Regulação Enzimológica da Expressão Gênica , Sulfeto de Hidrogênio/metabolismo , Animais , Cistationina gama-Liase/genética , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/fisiopatologia , Gastroparesia/genética , Gastroparesia/fisiopatologia , Masculino , Técnicas de Cultura de Órgãos , Ratos , Ratos Wistar
9.
Indian J Nephrol ; 25(4): 206-12, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26199471

RESUMO

Vitamin E and C are well-known antioxidant vitamins. Oxidative stress is common in chronic kidney diseases. We evaluated 43 dialysis subjects prospectively in a cross-sectional survey. Serum vitamin E concentration was checked in all subjects; 37 cases underwent blood sampling for measurement of serum vitamin C. The enrolled subjects consisted of 12 (27.9%) peritoneal dialysis (PD) and 25 (58.1%) hemodialysis (HD) patients. Six (13.9%) patients were switched from PD to HD or vice versa. Serum concentration of vitamin E was normal, low and high in 9 (20.9%), 31 (72%) and 3 (7.1%) patients, respectively. There were no significant differences regarding age, gender, modality and duration of dialysis, and characteristics of dialysis sessions, mean serum blood urea nitrogen, and albumin levels between vitamin E deficient cases with those with normal serum vitamin E concentration (P > 0.05 for all). The serum vitamin C levels were low in 5 (13.5%) and normal in 32 (86.5%) patients. vitamin C deficiency was more prevalent in HD versus continuous ambulatory peritoneal dialysis patients (P = 0.128). Mean serum vitamin C concentration was higher in patients who were supplemented by vitamin C compared with those who didn't receive the vitamin supplement (P = 0.043). Vitamin E deficiency was a prevalent finding and supplementary vitamin C 30-60 mg/day was sufficient to prevent deficiency. Regular assessments of serum vitamin E level may be needed in dialysis centers.

10.
J Phys Condens Matter ; 24(11): 116002, 2012 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-22353943

RESUMO

We consider the spin-1/2 Heisenberg chain with alternating spin exchange in the presence of additional modulation of exchange on odd bonds with period 3. We study the ground state magnetic phase diagram of this hexamer spin chain in the limit of very strong antiferromagnetic (AF) exchange on odd bonds using the numerical Lanczos method and bosonization approach. In the limit of strong magnetic field commensurate with the dominating AF exchange, the model is mapped onto an effective XXZ Heisenberg chain in the presence of uniform and spatially modulated fields, which is studied using the standard continuum-limit bosonization approach. In the absence of additional hexamer modulation, the model undergoes a quantum phase transition from a gapped phase into the only one gapless Lüttinger liquid (LL) phase by increasing the magnetic field. In the presence of hexamer modulation, two new gapped phases are identified in the ground state at magnetization equal to [Formula: see text] and [Formula: see text] of the saturation value. These phases reveal themselves also in the magnetization curve as plateaus at corresponding values of magnetization. As a result, the magnetic phase diagram of the hexamer chain shows seven different quantum phases, four gapped and three gapless, and the system is characterized by six critical fields which mark quantum phase transitions between the ordered gapped and the LL gapless phases.

12.
Iran J Public Health ; 40(1): 41-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-23113053

RESUMO

BACKGROUND: Molecular epidemiology of measles virus (MV) is important, not only to measure the success of measles vaccination programs but also to monitor the circulation and elimination of the virus worldwide. In this study, we compared MV obtained from patients before the 2003 mass vaccination MR campaign and viruses detected after 2003 until 2008 in Iran. METHODS: The nucleoprotein (N) gene of 29 MV strains circulating in Iran between 2002 and 2008 were amplified by RT-PCR and subjected to sequence and phylogenetic analysis. RESULTS: Molecular characterization of MV studied here revealed that although the outbreaks in Iran were associated with MV genotype D4, the isolated viruses clearly belonged to several different lineages. Maximum and minimum homology within the 29 Iranian strains in our study was100% and 94.9% within the carboxyl terminus of the N gene, respectively. Using ClustalX program, the alignment of Iranian MV sequences showed nine lineages. CONCLUSION: This study provides the usefulness of MV sequence analysis for the demonstration of local interruption of indigenous strain transmission as well as providing a valuable means for monitoring the elimination processes of MV control.

13.
Iran Red Crescent Med J ; 13(3): 171-7, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22737458

RESUMO

BACKGROUND: Coronary artery bypass graft (CABG) is a treatment strategy to relieve the symptoms of coronary artery disease (CAD). Based on determining the long term outcome of CABG using SF-36 Health Related Quality Of Life (HRQOL) questionnaire, the present study was conducted in our center to determine the CABG results one-year after the operation. METHODS: Between March 2005 and August 2009, 112 patients with coronary heart disease (CHD) who underwent coronary artery bypass graft (CABG) were enrolled. Patients completed SF-36 HRQOL general health status questionnaire. Stepwise multiple linear regression models were used to detect independent variables predicting changes in each eight subscales of SF-36 questionnaire. RESULTS: The mean age of patients was 61.4±0.9 years and most of them were male with three vessel diseases that were on pump CABG. The mean physical and mental component summary scores were 59.5±0.9 and 60.2±0.9, respectively. Physical functioning (PF) and role physical (RP) improved in males. Regression models showed that there were some statistical models with low R-square to predict role emotional (RE), general health (GH), PF and RP according to ejection fraction after surgery, diabetes, pump type of CABG and male gender. CONCLUSION: CABG has led to higher and more satisfactory outcomes for PF, RP and RE but lower in other scales comparing with normative data of the society and one-year post-operative scores of other studies. It could mostly be attributed to unmodified risk factors and progression of existing comorbidities.

14.
Acta Virol ; 54(3): 205-10, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20822313

RESUMO

Prophylaxis of influenza A virus infections is based on the vaccines inducing antibodies to the major viral antigens, hemagglutinin (HA) and neuraminidase (NA). Since these antigens continuously change during virus replication in various hosts, only the currently circulating strains should be used in the vaccines. Besides, monitoring of the naturally occurring changes in HA, NA, and respective genes, especially those associated with resistance to the NA inhibitors is necessary. The NA genes of 30 Iranian isolates of influenza H1N1 virus from the seasons 2005-2009 were sequenced and subjected to the sequence and phylogenetic analyses. The seasonal isolates turned out to be closely related to the corresponding vaccine strains, except for the 2007-2008 isolates, which also displayed a higher nucleotide variation. A resistance to the NA inhibitors was found in the 2008-2009 isolates only. The average nucleotide identities of the isolates with corresponding vaccine strains for the years 2005-2009 were 98.83%, 98.55%, 98.7%, 97.55%, and 98.76%, respectively.


Assuntos
Vírus da Influenza A Subtipo H1N1/classificação , Vírus da Influenza A Subtipo H1N1/genética , Vacinas contra Influenza/genética , Influenza Humana/virologia , Neuraminidase/genética , Filogenia , Proteínas Virais/genética , Sequência de Aminoácidos , Humanos , Vírus da Influenza A Subtipo H1N1/enzimologia , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vacinas contra Influenza/química , Vacinas contra Influenza/classificação , Vacinas contra Influenza/isolamento & purificação , Influenza Humana/epidemiologia , Irã (Geográfico)/epidemiologia , Dados de Sequência Molecular , Neuraminidase/química , Alinhamento de Sequência , Análise de Sequência de DNA , Proteínas Virais/química
15.
Pak J Biol Sci ; 13(2): 83-7, 2010 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-20415142

RESUMO

The aim of present study was to investigate the effect of hydroalcoholic extract of Ruta chalepensis (Rutaceae) leaves on rat ileum contractility and possible mechanism(s) involved. Ruta chalepensis extract was prepared by maceration method (ethanol 70%). Terminal portion of ileum (2 cm) was dissected out from male Wistar rats and mounted in an organ bath containing air bubbled Tyrode solution with 1 g initial tension and ileal contraction induced by KCl (60 mM) was recorded. The spasmolytic effect of the cumulative concentrations of extracts (0.01-0.07 mg mL(-1)) was reduced after tissue incubation with L-NAME (100 microM, 20 min). Methylene blue (30 microM) reduced the extracts (0.01-0.07 mg mL(-1)) spasmolytic effect (p < 0.001). Furthermore, it seems that the portion relaxatory effect of Rue extract on the rat ileum may be due to nitric oxide and the antispasmodic activity of the extract was mainly through a cGMP-dependent mechanism.


Assuntos
GMP Cíclico/farmacologia , Íleo , Óxido Nítrico/farmacologia , Parassimpatolíticos/farmacologia , Extratos Vegetais , Ruta/química , Animais , Inibidores Enzimáticos/farmacologia , Íleo/efeitos dos fármacos , Íleo/fisiopatologia , Masculino , Contração Muscular/efeitos dos fármacos , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Cloreto de Potássio/farmacologia , Ratos , Ratos Wistar , Ruta/anatomia & histologia
16.
Scand J Clin Lab Invest ; 70(4): 259-63, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20380616

RESUMO

BACKGROUND: The production of free radicals and reactive oxygen species are important factors contributing to ischemia/reperfusion injury. Thus scavenging of the excess free radicals can be an important therapeutic approach. Beta carotene, a carotenoid pigment has a potent antioxidant property. The present study examined the effect of beta carotene administration on the level of renal content of antioxidants and lipid peroxidation following ischemia/reperfusion injury in the rat kidney. METHODS: Male adult Wistar rats (250-300 g) were exposed to 45 min of renal ischemia followed by 4 h of reperfusion. Beta carotene (10, 30 and 100 mg kg(-1)) or vehicle was administered for 5 days prior to ischemia. Renal content of antioxidants and the level of lipid peroxidation were measured after the reperfusion period. RESULTS: Our results showed that ischemia/reperfusion injury increased lipid peroxidation (p < 0.001) and decreased antioxidant (p < 0.001) in renal tissue. Pre-administration of beta carotene could attenuate these alterations (p < 0.05-p < 0.001), although not at all doses. Since beta carotene administration improved renal lipid peroxidation and antioxidants, it seems that beta carotene protects renal tissue against ischemia/reperfusion-induced oxidative damage.


Assuntos
Antioxidantes/metabolismo , Rim/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Traumatismo por Reperfusão/tratamento farmacológico , Vitaminas/uso terapêutico , beta Caroteno/uso terapêutico , Animais , Catalase/metabolismo , Glutationa Peroxidase/metabolismo , Rim/enzimologia , Masculino , Malondialdeído/metabolismo , Ratos , Ratos Wistar , Traumatismo por Reperfusão/metabolismo , Superóxido Dismutase/metabolismo
17.
Niger J Med ; 19(1): 58-61, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20232758

RESUMO

BACKGROUND: Psoriasis is a common chronic inflammatory disease with unpredictable prognosis. Given the immunomodulatory effects of statins, the present study was conducted to determine whether the addition of orally administered simvastatin to the topical betamethasone, a standard antipsoriatic treatment, can produce a more powerful therapeutic response against this clinical conundrum. METHOD: In a double-blind study, 30 patients with plaque type psoriasis were randomly divided into two equal treatment groups. Group 1 received oral simvastatin (40 mg/d) plus topical steroid (50% betamethasone in petrolatum) for 8 weeks and group 2 received oral placebo plus the same topical steroid for the same time period. Psoriasis Area and Severity Index (PASI) score was checked before and at the end of the treatment period. RESULTS: PASI score decreased significantly in both groups, but the decline of PASI score was more significant in patients who received simvastatin (Mann-Whitney test; P-value = 0.001). No side effect or any laboratory abnormality was detected in patients. CONCLUSION: Our work, which is the first double-blind, randomized, placebo-controlled study on this subject, shows that oral simvastatin enhances the therapeutic effect of topical steroids against psoriasis. The increased risk of cardiovascular accidents in psoriatic patients and the protective effect of statins against cardiovascular disease further encourages their use in the treatment of this clinical conundrum.


Assuntos
Anti-Inflamatórios/uso terapêutico , Betametasona/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Psoríase/tratamento farmacológico , Sinvastatina/administração & dosagem , Administração Oral , Administração Tópica , Adolescente , Adulto , Idoso , Método Duplo-Cego , Esquema de Medicação , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psoríase/patologia , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto Jovem
18.
Intervirology ; 53(2): 133-40, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20068347

RESUMO

OBJECTIVES: To study the antigenic variations in influenza A/H3N2 viruses circulating in Iran for characterization and phylogenetic relationships to vaccine strains. METHODS: RT-PCR, full sequencing of hemagglutinin (HA) and neuraminidase (NA) genes and analysis by sequence handling and phylogenetic programs were done. RESULTS: The HA sequences of 2007 isolates fell within the clade represented by the HA of A/Brisbane/10/07 and characterized by the amino acid changes relative to the HA of A/Wisconsin/67/05, G50E and K140I. The only isolate in 2006 fell within A/Berlin/02/06 with V112I and K173E changes. The 2005 isolates characterized by Y159F, S189N and S227P changes within A/California/07/04. In all isolates we had E190D which is important because this was responsible for the loss of ability of A/H3N2 viruses to bind to chicken red blood cells. There were some substitutions in the antigenic sites of the HA. Similar to other studies, conserved residues for catalytic sites and also framework sites of NA supporting the catalytic residues were detected. We had some changes in the variable regions of the NA head domain. CONCLUSION: Comparison between Iranian viruses and vaccine strains showed high similarity between them and vaccine strains used in the northern hemisphere.


Assuntos
Hemaglutininas Virais/genética , Vírus da Influenza A Subtipo H3N2/genética , Vacinas contra Influenza/genética , Influenza Humana/virologia , Neuraminidase/genética , Proteínas Virais/genética , Sequência de Aminoácidos , Substituição de Aminoácidos/genética , Análise por Conglomerados , Humanos , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Irã (Geográfico) , Dados de Sequência Molecular , Mutação de Sentido Incorreto , Filogenia , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência
19.
Iran J Public Health ; 39(4): 140-2, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-23113048

RESUMO

BACKGROUND: Respiratory virus infections in children are a leading cause of morbidity and mortality worldwide. METHODS: A total of 897 clinical specimens were collected from February 2007 to January 2008 and transported to the National Influenza Center. Two hundred and two samples belonged to children under the age of six from 897 specimens, described above, were selected. Then they were tested for influenza virus types and subtypes by real time PCR assay subsequently, the specimens were tested for RSV and hMPV by hemi-nested multiplex PCR and parainfluenza viruses type 1-4 by hemi-nested multiplex PCR and adenovirus by hemi-nested PCR. RESULTS: The throat swab was taken from the Kawasaki case with the history of chicken's contact. The specimen was tested for all influenza subtypes especially H5N1 and the results were negative. Meanwhile PCR was done for screening of other respiratory viruses that results came out positive for RSV and hMPV. CONCLUSION: In the present study, we demonstrated the possibility to detect dual infection caused by RSV and hMPV, but because of the extravagant pattern of this case, more investigation is suggested specially on Kawasaki patients.

20.
Niger. j. med. (Online) ; 19(1): 58-61, 2010.
Artigo em Inglês | AIM (África) | ID: biblio-1267318

RESUMO

Psoriasis is a common chronic inflammatory disease with unpredictable prognosis. Given the immunomodulatory effects of statins; the present study was conducted to determine whether the addition of orally administered simvastatin to the topical betamethasone; a standard antipsoriatic treatment; can produce a more powerful therapeutic response against this clinical conundrum. In a double-blind study; 30 patients with plaque type psoriasis were randomly divided into two equal treatment groups. Group 1 received oral simvastatin (40 mg/d) plus topical steroid (50betamethasone in petrolatum) for 8 weeks and group 2 received oral placebo plus the same topical steroid for the same time period. Psoriasis Area and Severity Index (PASI) score was checked before and at the end of the treatment period. PASI score decreased significantly in both groups; but the decline of PASI score was more significant in patients who received simvastatin (Mann-Whitney test; P-value=0.001). No side effect or any laboratory abnormality was detected in patients. Our work; which is the first doubleblind; randomized; placebo-controlled study on this subject; shows that oral simvastatin enhances the therapeutic effect of topical steroids against psoriasis. The increased risk of cardiovascular accidents in psoriatic patients and the protective effect of statins against cardiovascular disease further encourages their use in the treatment of this clinical conundrum


Assuntos
Betametasona/uso terapêutico , Placebos , Psoríase , Sinvastatina
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