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1.
Sci Rep ; 13(1): 12026, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37491444

RESUMO

Monitoring spatial and temporal trends of water use is of utmost importance to ensure water and food security in river basins that are challenged by water scarcity and climate change induced abnormal weather patterns. To quantify water consumption by the agriculture sector, continuous monitoring is required over different spatial scales ranging from field (< 1 ha) to basin. The demand driven requirement of covering large areas yet providing spatially distributed information makes the use of in-situ measurement devices unfeasible. Earth observation satellites and remote sensing techniques offer an effective alternative in estimating the consumptive use of water (Actual EvapoTranspiration (ETa) fluxes) by using periodic observations from the visible and infrared spectral region. Optical satellite data, however, is often hindered by noises due to cloud cover, cloud shadow, aerosols and other satellite related issues such as Scan Line Corrector (SLC) failure in Landsat 7 breaking the continuity of temporal observations. These gaps have to be statistically filled in order to compute aggregated seasonal and annual estimates of ETa. In this paper, we introduce an approach to develop a gap-filled multi-year monthly ETa maps at medium spatial resolution of 30 m. The method includes two major steps: (i) estimation of ETa using the python based implementation of surface energy balance model called PySEBAL and (ii) temporal interpolation using Locally Weighted Regression (LWR) model followed by spline based spatial interpolation to fill the gaps over time and space. The approach is applied to a large endorheic Lake Urmia Basin (LUB) basin with a surface area of ~ 52,970 km2 in Iran for the years 2013-2015 using Landsat 7 and 8 satellite data. The results show that the implemented gap filling approach could reconstruct the monthly ETa dynamics over different agriculture land use types, while retaining the high spatial variability. A comparison with a similar dataset from FAO WaPOR reported a very high correlation with R2 of 0.93. The study demonstrates the applicability of this approach to a larger basin which is extendible and reproducible to other geographical areas.

2.
J Mycol Med ; 28(4): 628-636, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30126717

RESUMO

OBJECTIVE: Candidiasis is one of the most opportunistic fungal infections in immunocompromised patients. The emergence of multidrug-resistant Candida species necessitates the development of novel antifungal agents. Seeking to the discovery of natural antifungal agents, this study aimed to synthesize a novel formulated nanocomposite containing Indolicidin (IN), antimicrobial peptide, and Graphene oxide (GO), kind of nanomaterial, against Candida growth using in vitro and in vivo experiments for the first time. METHODS: The formulated nanocomposite (GO-IN) synthetized and was characterized using scanning electron microscopy, X-ray power diffraction, and fourier transform infrared method analysis. The in vitro antifungal activity of fluconazole (FLU), GO, IN, and GO-IN was determined against Candida albicans (C. albicans) compared to control groups, cell cytotoxicity assay on human intestinal epithelial cells (IEP) and hemolytic activities were performed. Moreover, in vivo experiments of nanocomposite were assessed in BALB/c mice. RESULTS: Our results showed that nanocomposite had the highest inhibitory effect against C. albicans (MIC 3.12µg/mL) compared with flu (MIC 4µg/mL), IN (MIC 12.5µg/mL), and GO (MIC 6.25µg/mL). Viability of human intestinal cell line at the MIC concentration (3.12µg/mL) of nanocomposite (GO-IN) was detected as 60% (P<0.05). The results of hemolytic activity showed that nanocomposite cause 2.73% of red blood cell membrane damage. For in vivo experiments, infected mice were successfully treated with GO-IN once a day within 7 days. GO-IN treated group eliminated the Candida infection in the spleen and liver of BALB/c mice (P=0.001) similar to fluconazole. There was no significant difference in histological manifestations between flu and GO-IN groups. CONCLUSION: This study suggests that synergistic combination of GO and IN provide a new option, representing a potential therapeutic efficiency against disseminated candidiasis in an animal model as well as might be used as adjunct therapy in the management of candidiasis. However, further investigation is needed to evaluate the efficacy of the nanocomposite.


Assuntos
Antifúngicos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Candida albicans/efeitos dos fármacos , Candidíase/tratamento farmacológico , Grafite/química , Nanocompostos/química , Animais , Antifúngicos/administração & dosagem , Antifúngicos/síntese química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Candidíase/microbiologia , Candidíase/patologia , Células Cultivadas , Modelos Animais de Doenças , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Nanocompostos/ultraestrutura , Resultado do Tratamento
3.
J Biol Regul Homeost Agents ; 31(3): 683-689, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28956418

RESUMO

Smyrnium cordifolium as a wild plant is used in traditional medicine in Iran for the treatment of anxiety and insomnia. The anticonvulsant effect of this plant has not been studied to date, therefore this study aimed to evaluate the anticonvulsant effects of its essential oil and curzerene on seizure. Essential oil of the Smyrnium cordifolium plant was prepared by the hydro-distillation method. Gas chromatography and gas chromatography-mass spectroscopy analysis of the essential oil revealed its main components. Anticonvulsant effects of Smyrnium cordifolium essential oil (SCEO) and curzerene were examined on mice using the pentylentetrazole model (PTZ). Flumazenil (2 mg/kg, i.p) and naloxone (5 mg/kg, i.p) were injected into the relevant groups of mice to realize the anticonvulsant mechanism of SCEO and curzerene, respectively. The main identified components of the plant were curzerene (65.26%), δ-Cadinene (14.39%) and γ-elemene (5.15%), which comprised approximately 85.28% of SCEO. The ED50 values of SCEO and curzerene in the PTZ model were 223±15 and 0.25±0.09 mg/kg, respectively. Curzerene at the dosage of 0.4 mg/kg prolonged the onset time of seizure and decreased the duration of seizure among treated group compared to the saline group. At the dosage of 0.4 mg/kg, seizure and mortality protection rates for the treated group were 100%. Flumazenil and naloxone could suppress the anticonvulsant effects of SCEO and curzerene. It seems that SCEO and curzerene are useful for the treatment of absence seizure and this effect may be related to their effects on GABAergic and opioid systems.


Assuntos
Apiaceae/química , Benzodiazepinas/farmacologia , Antagonistas de Entorpecentes/farmacologia , Óleos Voláteis/farmacologia , Pentilenotetrazol/efeitos adversos , Convulsões , Animais , Benzodiazepinas/química , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Antagonistas de Entorpecentes/química , Óleos Voláteis/química , Pentilenotetrazol/farmacologia , Convulsões/induzido quimicamente , Convulsões/tratamento farmacológico , Convulsões/fisiopatologia
4.
J Biol Regul Homeost Agents ; 30(1): 55-65, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27049076

RESUMO

A key issue in the treatment of acute myeloid leukemia (AML) is the development of drug resistance to chemotherapeutic agents. Overexpression of myeloid cell leukemia-1 (Mcl-1), an anti-apoptotic protein, is associated with tumor progression and drug resistance in leukemia and several cancers. The purpose of this study was to investigate the effect of specific Mcl-1 small interference RNA (siRNA) on the proliferation and chemosensitivity of U-937 AML cell to etoposide. The siRNA transfection was conducted using Lipofectamine™ 2000. Quantitative real-time RT-PCR (qRT-PCR) and Western blot analysis were employed to measure the expression levels of mRNA and protein, respectively. To evaluate tumor cell growth after siRNA transfection, Trypan blue exclusion assay was conducted. The cytotoxic effects of siRNA and etoposide were determined using MTT assay on their own and in combination. DNA-histone ELISA and annexin-V/FITC assays were performed to study the apoptosis. Mcl-1 siRNA transfection significantly blocked the expression of Mcl-1 mRNA and protein in a time-dependent manner, leading to a strong growth inhibition and enhanced apoptosis (P less than 0.05). Furthermore, pretreatment with Mcl-1 siRNA, synergistically enhanced the cytotoxic and apoptotic effects of etoposide (P less than 0.05). Our results demonstrated that Mcl-1 plays a fundamental role in the survival and resistance of U-937 cells to etoposide. Therefore, Mcl-1 can be considered an attractive target in gene therapy of AML patients and siRNA-mediated silencing of this gene may be a novel strategy in AML treatment.


Assuntos
Etoposídeo/farmacologia , Inativação Gênica/efeitos dos fármacos , Leucemia/genética , RNA Interferente Pequeno/metabolismo , Apoptose/efeitos dos fármacos , Apoptose/genética , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Interações Medicamentosas , Sinergismo Farmacológico , Citometria de Fluxo , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Leucemia/patologia , Proteína de Sequência 1 de Leucemia de Células Mieloides , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transfecção , Células U937
5.
Ann Nutr Metab ; 68(2): 85-93, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26655398

RESUMO

AIMS: This trial aims to determine the effects of resistant starch (RS) subtype 2 (RS2) on glycemic status, metabolic endotoxemia and markers of oxidative stress. METHODS: A randomized, controlled, parallel-group clinical trial group of 56 females with type 2 diabetes mellitus (T2DM) was divided to 2 groups. The intervention group (n = 28) and control group (n = 28) received 10 g/day RS2 or placebo for 8 weeks, respectively. Fasting blood samples were taken to determine glycemic status, endotoxin, high sensitivity C-reactive protein (hs-CRP), malondialdehyde (MDA), total antioxidant capacity (TAC), antioxidant enzymes concentrations as well as uric acid at baseline and after the intervention. RESULTS: After 8 weeks, RS2 caused a significant decrease in the levels of MDA (-34.10%), glycosylated hemoglobin (-9.40%), insulin (-29.36%), homeostasis model of insulin resistance (-32.85%) and endotoxin (-25.00%), a significant increase in TAC (18.10%) and glutathione peroxidase (11.60%) as compared with control. No significant changes were observed in fasting plasma glucose, quantitative insulin sensitivity check index, hs-CRP, superoxide dismutase, catalase and uric acid in the RS2 group as compared with the control group. CONCLUSION: Supplementation with RS2 may be improved glycemic status, endotoxemia and markers of oxidative stress in patients with T2DM.


Assuntos
Antioxidantes/metabolismo , Diabetes Mellitus Tipo 2/dietoterapia , Endotoxemia/tratamento farmacológico , Resistência à Insulina , Estresse Oxidativo/efeitos dos fármacos , Amido/uso terapêutico , Adulto , Idoso , Biomarcadores , Glicemia , Peso Corporal , Proteína C-Reativa/análise , Proteína C-Reativa/metabolismo , Endotoxinas/sangue , Feminino , Humanos , Malondialdeído/metabolismo , Pessoa de Meia-Idade , Ácido Úrico/metabolismo
6.
Genet Mol Res ; 12(3): 3551-4, 2013 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-24065688

RESUMO

Multiple sclerosis (MS) is an immunological inflammatory disease of the central nervous system. The pathogenesis of MS is incompletely understood, but various studies have suggested that mitochondrial dysfunction is associated with the disease. Mitochondria are among the main cellular sources of reactive oxygen and nitrogen species, and they play a pivotal role in many neuro-pathological conditions. The mitochondrial nuclear subunit of complex I gene in mitochondria may play a role in MS, and understanding this role may provide rationale for novel approaches to treatment of the disease and the development of novel therapies. We designed a molecular study to demonstrate biochemical defects in complex I activity and found some novel nucleotide substitutions in mitochondrial DNA that might be involved in the pathogenesis of MS. The mitochondrial complex subunit I sequence was amplified and sequenced in MS patients. Although no reported pathogenic mutations were found in these patients, other studies have clearly indicated that the mitochondrial nuclear complex subunit I gene plays a significant role in MS pathogenesis.


Assuntos
Núcleo Celular/genética , Complexo I de Transporte de Elétrons/deficiência , Mitocôndrias/genética , Doenças Mitocondriais/genética , Esclerose Múltipla/genética , DNA Mitocondrial/genética , Complexo I de Transporte de Elétrons/genética , Complexo I de Transporte de Elétrons/metabolismo , Humanos , Doenças Mitocondriais/metabolismo , Esclerose Múltipla/metabolismo , Esclerose Múltipla/patologia , Mutação , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo
7.
Appl Opt ; 52(21): 5088-96, 2013 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-23872753

RESUMO

Aluminum spectra in the noble gases of helium and argon at initial delay times after plasma formation are numerically calculated. Temporal behavior of plasma emissions up to 200 ns after laser irradiation is investigated. Plasma parameters are computed by coupling the thermal model of laser ablation, hydrodynamic of plasma expansion, and Saha-Eggert equations. A spectrum is constructed from the superposition of 13 strong lines of aluminum and several strong lines of ambient gases. Spectral radiations are superimposed on a continuous emission composed of bremsstrahlung and recombination radiation. The self-absorption effect on plasma radiation at 1 atm gas pressure is studied. In this paper, a comparison between thin and thick aluminum radiation is done. Furthermore, the self-absorption coefficient of each strong line at laser energies of 0.5, 0.7, 0.9, and 1.1 GW/cm(2) is estimated. Results show that at specific laser energy, the self-absorption effect in argon is more significant than in helium. For most of the spectral lines in both noble gases, the self-absorption coefficient will diminish with the delay time. As indicated with passing time, the line widths of the self-absorbed lines will rise. More intense continuous emissions are observed at higher wavelengths, and these radiations will be increased with laser energy.

8.
ScientificWorldJournal ; 2012: 615670, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23213292

RESUMO

To probe the physiological and biochemical tolerance mechanisms in Astragalus neo-mobayenii Maassoumi, an endemic plant around the Cu-rich areas from the North West of Iran, the effect of different copper concentrations at toxic levels on this plant was investigated. Copper was applied in the form of copper sulfate (CuSO4·5H2O) in four levels (0, 50, 100, and 150 µM). We observed no visible symptoms of Cu toxicity in this plant species. During the exposure of plants to excess copper, the antioxidant defense system helped the plant to protect itself from the damage. With increasing copper concentration, superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) activities increased in leaves and roots (P < 0.001) compared with that of the control group. The chlorophyll amount gradually declined with increasing Cu concentrations. However, reduction in the 50 µM level showed insignificant changes. Enhanced accumulation of proline content in the leaves was determined, as well as an increase of MDA content (oxidative damage biomarker) (P < 0.001). The results indicated that Cu contents in leaves and roots enhanced with increasing levels of Cu application. The Fe and Mn contents in both shoots and roots significantly decreased with increasing Cu concentration. Finally, the mechanisms of copper toxicity and copper tolerance in this plant were briefly discussed.


Assuntos
Astrágalo/metabolismo , Clorofila/metabolismo , Cobre/administração & dosagem , Peroxidação de Lipídeos/fisiologia , Metais/metabolismo , Oxirredutases/metabolismo , Prolina/metabolismo , Antioxidantes/metabolismo , Astrágalo/efeitos dos fármacos , Relação Dose-Resposta a Droga , Peroxidação de Lipídeos/efeitos dos fármacos
9.
Pak J Biol Sci ; 10(24): 4505-9, 2007 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-19093520

RESUMO

In present study, All samples collected from Kalybar and Ahar districts in Northwest of Iran from 12 patients (bone marrow aspirates), 26 dogs (spleenic and hepatic aspirates) and more than 100 sand flies between years 2004-2006. All patients were clinically diagnosed to have visceral leishmaniasis. Serological profiles of all sera samples from both human and dogs were in accordance with leishmaniasis (DAT). Isoenzyme profiles of these isolates were compared with those of reference using 12 enzyme systems. L. infuntum MON-1 is the only zymodeme present in all samples of dogs, sand flies and human. The enzymatic polymorphism is compared to that of neighboring countries (Azarbaijan, Iraq and Turkey etc.) and we concluded that the Visceral Leishmaniasis (VL) focus in northwest of Iran is evidently Mediterranean focus of zoonotic VL, which extends from Portugal and Morocco to Pakistan and the central Asian republics. Domestic doges act as the reservoir host, where Phlebotomus kandellakii and Perfiliewi ariasi are vectors.


Assuntos
Leishmania infantum/classificação , Leishmania infantum/genética , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/veterinária , Polimorfismo Genético , Animais , Medula Óssea/parasitologia , Doenças do Cão/parasitologia , Cães/parasitologia , Feminino , Humanos , Irã (Geográfico) , Isoenzimas/genética , Isoenzimas/isolamento & purificação , Leishmania infantum/enzimologia , Leishmania infantum/isolamento & purificação , Fígado/parasitologia , Psychodidae/parasitologia , Baço/parasitologia
10.
Pediatr Infect Dis J ; 19(2): 138-43, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10694001

RESUMO

OBJECTIVE: To determine the impact of respiratory syncytial virus (RSV) prophylaxis among preterm infants of < or =32 weeks gestation by comparing the severity of illness and cost of RSV-related care during the two winter seasons before (1994 to 1995, 1995 to 1996) with the two seasons after initiation of prophylaxis (1996 to 1997, 1997 to 1998). METHODS: Preterm infants of < or =32 weeks gestation at risk for hospitalization with RSV infection were identified retrospectively from the infants hospitalized in our neonatal units. Infants were included if they (1) were born 6 months before or during four winter seasons (1994 to 1998), (2) were discharged from the neonatal unit and (3) had remained in the university outpatient clinic system during at least the first winter of life. Preterm infants of < or =32 weeks gestation hospitalized with RSV were identified from our RSV database (which includes cost of hospitalization, duration of hospital stay, pediatric intensive care unit stay and intubation). Infants receiving prophylaxis were identified prospectively. RESULTS: The incidence of hospitalization with RSV was significantly lower among the cohort of infants born after initiation of prophylaxis: 8.7% (17 of 195) vs. 22% (35 of 159), P = 0.00049 by two tailed Fisher's exact test. Among the cohort of infants born after initiation of prophylaxis (n = 195), 100 infants received prophylaxis. The gestational and chronologic ages of the prophylaxis-treated infants were significantly lower than those of the non-prophylaxis-treated infants (n = 95). The prophylaxis-treated infants also were more likely to have bronchopulmonary dysplasia. Only 1 (1%) of the prophylaxis-treated infants required hospitalization for RSV. Comparison of the cohort of infants born before initiation of prophylaxis to the cohort born after initiation of prophylaxis (includes prophylaxis-treated and non-prophylaxis-treated infants) revealed a significant reduction in severity of illness and cost. The length of stay in the cohort born before initiation of prophylaxis was reduced 83.8%: 373.6 days per 100 infants at risk vs. 60.5 (P = 0.00055). The length of stay in the pediatric intensive care unit was reduced 92.7%: 218.2 days per 100 infants at risk vs. 15.9 (P = 0.00029). The duration of intubation was reduced 95.6%: 187.4 days per 100 infants at risk vs. 8.2 (P = 0.00024). The dollars spent for RSV-related care (hospitalizations and prophylaxis) per 100 infants at risk for RSV was reduced 65% in the cohort of infants born after prophylaxis: $670,590 per 100 infants at risk vs. $234,596 (P = 0.00056). This reduction remained significant (64.9%) if the cost of ribavirin (drug and administration fees) was excluded from the cost of hospitalization. CONCLUSIONS: These data reveal that RSV prophylaxis significantly reduced the incidence of RSV hospitalizations and severity of illness as well as the cost of RSV-related care among these infants.


Assuntos
Imunoglobulinas Intravenosas/uso terapêutico , Doenças do Prematuro/prevenção & controle , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Vírus Sinciciais Respiratórios/imunologia , Feminino , Idade Gestacional , Hospitalização , Humanos , Imunoglobulinas Intravenosas/administração & dosagem , Imunoglobulinas Intravenosas/economia , Incidência , Recém-Nascido , Recém-Nascido Prematuro , Doenças do Prematuro/economia , Doenças do Prematuro/virologia , Masculino , Infecções por Vírus Respiratório Sincicial/economia , Infecções por Vírus Respiratório Sincicial/virologia , Índice de Gravidade de Doença , Estados Unidos
11.
Bull Soc Pathol Exot Filiales ; 73(1): 28-35, 1980.
Artigo em Francês | MEDLINE | ID: mdl-7418121

RESUMO

The surveillance of territories surrounding the plague focus of Kurdistan province in Iran, by inspection of wild rodent burrows, permit to reveal the existence of an epizootic in a new focus located in the Eastern Azarbaidjan province, where plague was never reported. 14 strains of Y. pestis were isolated from Meriones vinogradovi, M. persicus Mesocricetus brandti and from the fleas: Xenopsylla conformis and Nosopsylla iranus iranus. The eventual relationship between these two areas separated by about 200 km was investigated: neither attempts to isolate Y. pestis nor serological surveys permit to reveal any sign of plague enzootic in the zone between the Kurdistan focus and the new described focus of the Eastern Azarbaidjan.


Assuntos
Surtos de Doenças/veterinária , Peste/veterinária , Doenças dos Roedores/epidemiologia , Zoonoses/epidemiologia , Animais , Surtos de Doenças/epidemiologia , Irã (Geográfico) , Peste/epidemiologia , Roedores
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