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1.
J Nanobiotechnology ; 21(1): 199, 2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37344894

RESUMO

Viruses are a major cause of mortality and socio-economic downfall despite the plethora of biopharmaceuticals designed for their eradication. Conventional antiviral therapies are often ineffective. Live-attenuated vaccines can pose a safety risk due to the possibility of pathogen reversion, whereas inactivated viral vaccines and subunit vaccines do not generate robust and sustained immune responses. Recent studies have demonstrated the potential of strategies that combine nanotechnology concepts with the diagnosis, prevention, and treatment of viral infectious diseases. The present review provides a comprehensive introduction to the different strains of viruses involved in respiratory diseases and presents an overview of recent advances in the diagnosis and treatment of viral infections based on nanotechnology concepts and applications. Discussions in diagnostic/therapeutic nanotechnology-based approaches will be focused on H1N1 influenza, respiratory syncytial virus, human parainfluenza virus type 3 infections, as well as COVID-19 infections caused by the SARS-CoV-2 virus Delta variant and new emerging Omicron variant.


Assuntos
COVID-19 , Vírus da Influenza A Subtipo H1N1 , Nanoestruturas , Pneumonia , Viroses , Humanos , SARS-CoV-2 , COVID-19/diagnóstico , COVID-19/prevenção & controle , Nanoestruturas/uso terapêutico , Teste para COVID-19
2.
J Cell Physiol ; 233(9): 6790-6797, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29319161

RESUMO

Viper venom contains antibacterial and cytotoxic components. The aim of this study was to identify and evaluate the antimicrobial and cytotoxic properties of the crude venom of Vipera latifii (V. latifii). Lyophilized venom of V. latifii was quantified by Bradford method and its antibacterial activity (6.25-400 µg/ml) was assessed using the MTT, MIC, Disc diffusion, and Well diffusion assays. Also, its cytotoxic activity was investigated using MTT reduction, Neutral uptake, and Comet assay on human liver cancer (HepG2) cell line. Crude venom showed antibacterial effects against Bacillus subtilis and Staphylococcus aureus, but was not effective on Escherichia coli. Also, the crude venom showed apoptotic and necrotic effects on human liver cancer cells. The venom of V. latifii can inhibit the growth of bacteria and cancer cells. These findings suggest that this may be a potential source of molecules with antibacterial and anticancer characteristics.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Venenos de Víboras/farmacologia , Animais , Bacillus subtilis/efeitos dos fármacos , Linhagem Celular Tumoral , Escherichia coli/efeitos dos fármacos , Células Hep G2 , Humanos , Irã (Geográfico) , Serpentes/metabolismo , Staphylococcus aureus/efeitos dos fármacos
3.
Sci Rep ; 13(1): 1057, 2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36658205

RESUMO

The agriculture sector provides the majority of food supplies, ensures food security, and promotes sustainable development. Due to recent climate changes as well as trends in human population growth and environmental degradation, the need for timely agricultural information continues to rise. This study analyzes and predicts the impacts of climate change on food security (FS). For 2002-2021, Landsat, MODIS satellite images and predisposing variables (land surface temperature (LST), evapotranspiration, precipitation, sunny days, cloud ratio, soil salinity, soil moisture, groundwater quality, soil types, digital elevation model, slope, and aspect) were used. First, we used a deep learning convolutional neural network (DL-CNN) based on the Google Earth Engine (GEE) to detect agricultural land (AL). A remote sensing-based approach combined with the analytical network process (ANP) model was used to identify frost-affected areas. We then analyzed the relationship between climatic, geospatial, and topographical variables and AL and frost-affected areas. We found negative correlations of - 0.80, - 0.58, - 0.43, and - 0.45 between AL and LST, evapotranspiration, cloud ratio, and soil salinity, respectively. There is a positive correlation between AL and precipitation, sunny days, soil moisture, and groundwater quality of 0.39, 0.25, 0.21, and 0.77, respectively. The correlation between frost-affected areas and LST, evapotranspiration, cloud ratio, elevation, slope, and aspect are 0.55, 0.40, 0.52, 0.35, 0.45, and 0.39. Frost-affected areas have negative correlations with precipitation, sunny day, and soil moisture of - 0.68, - 0.23, and - 0.38, respectively. Our findings show that the increase in LST, evapotranspiration, cloud ratio, and soil salinity is associated with the decrease in AL. Additionally, AL decreases with a decreasing in precipitation, sunny days, soil moisture, and groundwater quality. It was also found that as LST, evapotranspiration, cloud ratio, elevation, slope, and aspect increase, frost-affected areas increase as well. Furthermore, frost-affected areas increase when precipitation, sunny days, and soil moisture decrease. Finally, we predicted the FS threat for 2030, 2040, 2050, and 2060 using the CA-Markov method. According to the results, the AL will decrease by 0.36% from 2030 to 2060. Between 2030 and 2060, however, the area with very high frost-affected will increase by about 10.64%. In sum, this study accentuates the critical impacts of climate change on the FS in the region. Our findings and proposed methods could be helpful for researchers to model and quantify the climate change impacts on the FS in different regions and periods.


Assuntos
Mudança Climática , Tecnologia de Sensoriamento Remoto , Humanos , Solo , Agricultura/métodos , Segurança Alimentar
4.
ARYA Atheroscler ; 16(6): 301-305, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34122585

RESUMO

BACKGROUND: Myocardial infarction (MI) is a multifactorial disease caused by the suspension of blood circulation in a part of the myocardium. Understanding the genetic basis of MI can provide insight regarding the pathogenesis of the disease. The aim of this study was to investigate the association between pathogenic mutations and early-onset MI in five families with familial MI and without common MI risk factor. METHODS: Patients with MI younger than 50 years with family history of MI and without common diagnostic criteria (obesity, diabetes, familial hypercholesterolemia, opium/alcohol use) were evaluated for pathogenic mutations by whole exome sequencing (WES) and mutation was confirmed by polymerase chain reaction (PCR)-Sanger sequencing. RESULTS: The c.2855G > A missense mutation with homozygous autosomal recessive inheritance was identified in low-density lipoprotein receptor-related protein 8 (LRP8) gene in all patients of a family. CONCLUSION: The c.2855G > A (R952Q) mutation in LRP8 gene in homozygous state could be considered as a possible etiology of early-onset familial MI.

5.
Eur J Epidemiol ; 24(6): 297-306, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19357974

RESUMO

Previous studies have shown controversial results about the role of androgens in coronary artery disease (CAD). We performed this study to examine and compare the relationship between androgenic hormones and CAD using conventional linear statistical techniques as well as novel non-linear approaches. The study was conducted on 502 consecutive men who were referred for selective coronary angiography at Tehran Heart Center due to different indications. We studied the relationship between androgenic hormones and CAD by using the generalized linear models, generalized additive models, and neural networks. Free testosterone (fT), total testosterone (tT) and dehydroepiandrosterone sulfate levels in patients with significant CAD versus normal individuals were 6.69 +/- 3.20 pg/ml, 16.60 +/- 6.66 nm/l, and 113.38 +/- 72.9 microg/dl versus 7.12 +/- 3.58 pg/ml, 15.82 +/- 7.26 nm/l, and 109.03 +/- 68.19 microg/dl, respectively (P > 0.05). The Generalized linear models was unable to show any significant relationship between androgenic hormones and CAD, while generalized additive model and neural networks supported the significant effect of androgenic hormones on CAD. This finding suggests a nonlinear association of tT levels with CAD: lower levels have a preventive effect on CAD, whereas higher values increase the risk of CAD. Emphasizing the non-linearity of the variables may provide new insight into the possible explanation of the effect of androgenic hormones on CAD.


Assuntos
Doença da Artéria Coronariana/epidemiologia , Dinâmica não Linear , Testosterona/sangue , Adulto , Idoso , Angiografia Coronária , Doença da Artéria Coronariana/sangue , Humanos , Irã (Geográfico)/epidemiologia , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Fatores de Risco
6.
Int J Biol Macromol ; 126: 620-632, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30562517

RESUMO

Corneal disease is considered as the second leading cause of vision loss and keratoplasty is known as an effective treatment for it. However, the tissue engineered corneal substitutes are promising tools in experimental in vivo repair of cornea. Selecting appropriate cell sources and scaffolds are two important concerns in corneal tissue engineering. The object of this study was to investigate biocompatibility and physical properties of the bio-engineered cornea, fabricated from type-I collagen (COL) and gelatin (Gel). Two gelatin based hydrogels cross-linked with EDC/NHS were fabricated, and their physicochemical properties such as equilibrium water content, enzymatic degradation, mechanical properties, rheological, contact angle and optical properties as well as their ability to support human bone-marrow mesenchymal stem cells (hBM-MSCs) survival were characterized. The equilibrium water content and enzymatic degradation of these hydrogels can be easily controlled by adding COL. Our findings suggest that incorporation of COL-I increases optical properties, hydrophilicity, stiffness and Young's modulus. The viability of hBM-MSCs cultured in Gel and Gel: COL was assessed via CCK-8 assay. Also, the morphology of the hBM-MSCs on the top of Gel and Gel: COL hydrogels were characterized by phase-contrast microscopy. This biocompatible hydrogel may promise to be used as artificial corneal substitutes.


Assuntos
Colágeno/síntese química , Córnea/fisiologia , Reagentes de Ligações Cruzadas/síntese química , Gelatina/síntese química , Hidrogéis/síntese química , Succinimidas/química , Engenharia Tecidual/métodos , Animais , Proliferação de Células/efeitos dos fármacos , Fenômenos Químicos , Colágeno/farmacologia , Colagenases/metabolismo , Gelatina/farmacologia , Cabras , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/ultraestrutura , Fenômenos Ópticos , Reologia , Espectroscopia de Infravermelho com Transformada de Fourier , Suínos , Água/química
7.
Tissue Eng Regen Med ; 16(3): 237-251, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31205853

RESUMO

Background: Nowadays, production of nanocomposite scaffolds based on natural biopolymer, bioceramic, and metal ions is a growing field of research due to the potential for bone tissue engineering applications. Methods: In this study, a nanocomposite scaffold for bone tissue engineering was successfully prepared using collagen (COL), beta-tricalcium phosphate (ß-TCP) and strontium oxide (SrO). A composition of ß-TCP (4.9 g) was prepared by doping with SrO (0.05 g). Biocompatible porous nanocomposite scaffolds were prepared by freeze-drying in different formulations [COL, COL/ß-TCP (1:2 w/w), and COL/ß-TCP-Sr (1:2 w/w)] to be used as a provisional matrix or scaffold for bone tissue engineering. The nanoparticles were characterized by X-ray diffraction, Fourier transforms infrared spectroscopy and energy dispersive spectroscopy. Moreover, the prepared scaffolds were characterized by physicochemical properties, such as porosity, swelling ratio, biodegradation, mechanical properties, and biomineralization. Results: All the scaffolds had a microporous structure with high porosity (~ 95-99%) and appropriate pore size (100-200 µm). COL/ß-TCP-Sr scaffolds had the compressive modulus (213.44 ± 0.47 kPa) higher than that of COL/ß-TCP (33.14 ± 1.77 kPa). In vitro cytocompatibility, cell attachment and alkaline phosphatase (ALP) activity studies performed using rat bone marrow mesenchymal stem cells. Addition of ß-TCP-Sr to collagen scaffolds increased ALP activity by 1.33-1.79 and 2.92-4.57 folds after 7 and 14 days of culture, respectively. Conclusion: In summary, it was found that the incorporation of Sr into the collagen-ß-TCP scaffolds has a great potential for bone tissue engineering applications.


Assuntos
Osso e Ossos , Fosfatos de Cálcio/metabolismo , Colágeno/química , Nanocompostos/química , Estrôncio/química , Engenharia Tecidual/métodos , Alicerces Teciduais , Animais , Sobrevivência Celular , Liofilização , Células-Tronco Mesenquimais , Ratos
8.
Artigo em Inglês | MEDLINE | ID: mdl-30863800

RESUMO

INTRODUCTION: Coronary artery diseases (CAD) are the most common causes of death. Myocardial infarction (MI) is a complex multifactorial and the most severe type of CAD. Early onset MI in a first-degree relative could be defined as an independent risk factor for CAD. This study was performed to investigate the genetic cause of early onset familial CAD. MATERIAL AND METHODS: In this study, the genetic cause of familial CAD was investigated in patients with a family history of CAD who underwent angiography before the age of 50 years. The patients did not have any diagnostic criteria for familial hypercholesterolemia, diabetes, or obesity, and also they were not opium or alcohol users. Whole exome sequencing in probands was performed and mutation was confirmed by PCR and Sanger sequencing. RESULTS: In our studied population, the c.501G>C (p.K167N) mutation in the OLR1 gene was identified in a family. Mutation was confirmed by PCR and Sanger sequencing in the homozygous state (GG) in patients. Healthy individuals in this family were heterozygous (GC) and homozygous (CC). CONCLUSIONS: This finding suggests that the OLR1 gene could be a possible cause of early onset familial MI. Considering that parents of all affected individuals had a consanguineous marriage, it is important to perform carrier screening and genetic counseling in this family and their close relatives as a prevention strategy in populations at risk.

9.
J Arthropod Borne Dis ; 10(2): 237-44, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27308281

RESUMO

BACKGROUND: Latrodectism, a syndrome caused by Latrodectus genus, is one of the clinical problems that occur predominantly in north east of Iran. Nowadays antivenom therapy has become the most useful treatment for animal bites; however there is still a controversy about route and time of antivenom administration in spider bite. The aim of the present study was to determine the efficacy of specific antivenom in neutralizing hepatic and renal symptoms 24 h after Latrodectus dahli envenomation. METHODS: We selected a group of male New Zealand white rabbits, weighing 2±0.3 kg. The L. dahli venom (0.5 mg/kg) was injected subcutaneously. Specific antivenom (2.5 ml, I.V) was injected 24 h following venom injection. Blood sampling was performed before and 24 h after venom injection, as well within 24, 48 and 72 h after antivenom administration. Serum levels of (aspartate amino transferase (AST) alanine amino transferase (ALT), alkaline phosphatase (ALP), urea, bilirubin, creatinine and albumin were determined in all the sam. RESULTS: Latrodectus dahli venom caused significant increase (P< 0.05) in all foresaid serum parameters. Antivenom reversed the AST, ALP, creatinine, urea and bilirubin to normal levels, but failed about ALT level, also non-significant decrease was observed in albumin levels. CONCLUSION: Antivenom administration 24 h after venom injection can greatly reverse symptoms caused by venom. Future studies in human beings should be conducted to assess the protection against the specific-Latrodectus anti-venom.

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