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1.
J Photochem Photobiol B ; 188: 6-11, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30176393

RESUMO

A simple, inexpensive ultra-sonication method was used to synthesize quasi spherical silver nanoparticles (AgNPs) with an aqueous extract from Panax ginseng roots. This method has the advantages of being completely eco-friendly and allows increased reaction rates, uniform dispersal of the nanoparticles in liquids, and effective breaking of aggregates. Biomolecules present in plant extracts are often used to reduce metal ions to nanoparticles in a single-step green synthesis route. The formation of the AgNPs was characterized using UV-visible (UV-vis) spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), energy- dispersive X-ray analysis (EDX), Fast Fourier Transform (FFT), and high-resolution transmission electron microscopy (HR-TEM). The formation of AgNPs (456 nm) was confirmed by UV-vis spectroscopy. HR-TEM analysis revealed that most of the AgNPs were quasi spherical with sizes ranging from approximately 5 to 15 nm. The crystalline nature of the AgNPs was confirmed by XRD, and the presence of elemental silver was confirmed by energy-dispersive X -ray analysis. The AgNPs showed dose-dependent cytotoxicity towards HeLa cells in vitro (3.88% at 0.005 M, 5.11% at 0.01 M, 7.52% at 0.015 M, 11.19% at 0.02 M, and 19.45% at 0.025 M) as revealed by sulforhodamine B assay. They were also shown to be virucidal against the influenza A virus (strain A/PR/8). Hence, the present facile, eco-friendly, and efficient method results in the synthesis of AgNPs that can act as an alternative biomaterial for future biomedical applications.


Assuntos
Nanopartículas Metálicas/química , Panax/química , Extratos Vegetais/química , Prata/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Antivirais/química , Antivirais/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Química Verde , Células HeLa , Humanos , Vírus da Influenza A/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Microscopia Eletrônica de Transmissão , Panax/metabolismo , Tamanho da Partícula , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Sonicação , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier
2.
J Nutr Health Aging ; 20(5): 486-93, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27102784

RESUMO

Catecholamines regulate a variety of cellular functions in the mammalian kidney. The present study was aimed to investigate the differential sensitivity of Madin-Darby Kidney Cells (MDCK cells) to epinephrine in a dose-dependent manner. The loss of adhesion and altered cell shape were observed in MDCK cells. The presence of apoptosis and necrosis were studied by the fluorescence microscope and Confocal Laser Scanning Microscope (CLSM). Scanning Electron Microscope (SEM) analysis showed several surface microvilli, and cells were rounded having ruffled and crenated surface. Agarose gel electrophoresis study showed the presence of smearing, which further confirms the occurrence of necrosis. The fluorescence staining study showed the increased reactive oxygen species (ROS) level. Up-regulation of p53, bax, and caspase 3 mRNA expressions was evidenced by quantitative PCR (qPCR). Caspase 3 activity was also increased in epinephrine treated cells. Our experimental results do not imply that the epinephrine should not be used in the clinical treatments. However, our results add a research note of caution on the possible cytotoxic effect of maximal doses of epinephrine over a prolonged time.


Assuntos
Epinefrina/metabolismo , Rim/metabolismo , Animais , Cães , Rim/efeitos dos fármacos , Células Madin Darby de Rim Canino/efeitos dos fármacos , Células Madin Darby de Rim Canino/patologia
3.
GM Crops ; 2(3): 135-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22233571

RESUMO

Bacillus thuringiensis (Bt), a gram positive soil bacteria was first identified and named by Japanese microbiologist Shigetane Ishiwata in 1901. During sporulation Bt produces proteinaceous parasporal crystal proteins called δ-endotoxins, or Cry proteins, which are insecticidal. Numerous Cry proteins have been isolated and characterized from different Bt strains with activity against insects, mites and nematodes. Sprayable formulations containing these Cry proteins as active ingredients have contributed significantly in the field of insect pest management. Since the first cloning of cry genes from Bt,1 scientists have successively demonstrated that plants could be genetically engineered to express these cry genes for the control of dreadful insect pests. Eventually, the first transgenic crop expressing Btcry1Ac gene in cotton was approved in 1996 for commercial cultivation in the USA to manage bollworms.


Assuntos
Proteínas de Bactérias/genética , Endotoxinas/genética , Proteínas Hemolisinas/genética , Oryza/genética , Plantas Geneticamente Modificadas/genética , Animais , Bacillus thuringiensis/genética , Toxinas de Bacillus thuringiensis , Biomassa , Humanos , Oryza/crescimento & desenvolvimento , Controle Biológico de Vetores/métodos , Controle Biológico de Vetores/tendências , Plantas Geneticamente Modificadas/crescimento & desenvolvimento
4.
Prep Biochem Biotechnol ; 40(4): 256-62, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21108129

RESUMO

The subchronic effect of the plant hormone homobrassinolide, a dietary constituent of vegetables and green leaves, was investigated in male albino Wistar strain rats. Blood sugar and serum insulin content, tissue hexokinase enzyme activity, and mRNA expression were studied using homobrassinolide administered orally by gavage at 50 µg (333 µg/kg body weight) for 15 consecutive days. Selected tissue responses were determined at 16 days post administration in control and experimental animals employing established methods. Homobrassinolide reduced the circulating blood sugar and increased the serum insulin level significantly. Hexokinase activity in the brain, heart, liver, kidney, and testis of experimental rats was found elevated. Hexokinase mRNA expression detected employing polymerase chain reaction (PCR) technique was found significantly increased in the brain and liver compared to other tissues. It is suggested that this plant hormone is a transcriptional activator of hexokinase gene, promoting enhanced hexokinase mRNA synthesis in vivo in rat tissues.


Assuntos
Colestanonas/farmacologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Hexoquinase/genética , Reguladores de Crescimento de Plantas/farmacologia , RNA Mensageiro/genética , Animais , Glicemia/metabolismo , Colestanonas/administração & dosagem , Insulina/metabolismo , Masculino , Folhas de Planta/química , Plantas/química , Ratos , Ratos Wistar , Ativação Transcricional/efeitos dos fármacos
5.
Eur J Pharm Sci ; 41(1): 1-9, 2010 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-20570616

RESUMO

This study aimed to investigate the effect of the plant growth regulator 28-homobrassinolide (HB) on the hexokinase I (HK I) enzyme gene expression in the tissues of normal and streptozotocin-induced diabetic rats. Normal and diabetic rats were administered 50 microg of HB for 15 consecutive days. The tissues level of HK I mRNA expression was quantitated by PCR and densitometry analysis, HK I protein expression was quantitated by Western blot and densitometry analysis, localization of HK I was done by immunohistochemistry and HK enzyme activity was determined by coupled enzyme assay. Subchronic treatment of rats with HB enhanced HK I enzyme expression in diabetic rat compared to the control rat. From these experimental evidences, we came to the conclusion that HK I played a vital role in the regulation of blood sugar in streptozotocin-induced diabetic rats. A direct role for hexokinase enzyme activity in the control of diabetes is presented.


Assuntos
Colestanonas/farmacologia , Diabetes Mellitus Experimental/enzimologia , Hexoquinase/biossíntese , Animais , Sequência de Bases , Biocatálise , Western Blotting , Primers do DNA , Densitometria , Indução Enzimática , Hexoquinase/genética , Hexoquinase/metabolismo , Imuno-Histoquímica , Masculino , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , Ratos , Estreptozocina
6.
J Enzyme Inhib Med Chem ; 24(6): 1253-6, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19912059

RESUMO

Marine Spirulina platensis may potentially influence the metabolic process in animal cells, and the effect of marine Spirulina platensis in normal and alloxan-induced diabetic rats was therefore investigated. Normal and diabetic rats (albino Wistar strain) were orally administered marine Spirulina platensis for 30 days and their blood levels of glucose and insulin and body weight changes were determined. Pancreatic histopathology was also noted. Treatment with marine Spirulina platensis caused significant alterations in the content of these indicators and therefore in the antidiabetic capacity of the treated animals compared to control rats.


Assuntos
Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/farmacologia , Ilhotas Pancreáticas/efeitos dos fármacos , Spirulina , Aloxano , Animais , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Hipoglicemiantes/uso terapêutico , Insulina/sangue , Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/patologia , Masculino , Ratos , Ratos Wistar
7.
J Enzyme Inhib Med Chem ; 24(5): 1122-7, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19619070

RESUMO

Dietary content of phytohormones may potentially influence metabolic processes in animal cells. This study therefore aimed to investigate the effect of two plant growth regulators homobrassinolide (HB) and gibberellic acid (GBA) on the antioxidant defense status and lipid peroxidation level in the tissues of normal and streptozotocin- induced diabetic rats. Normal and diabetic rats (Albino -wistar strain) were administered 50 microg HB and GBA intradermally each day for seven days and their tissue and blood levels of malondialdehyde (MDA), 4-hydroxy-2-nonenol (4-HNE), reduced glutathione (GSH) content and catalase (CAT) activity were determined. Subchronic treatment of rats with HB reduced lipid perioxidation and elevated antioxidant defense whereas GBA caused enhancement of lipid peroxidation and reduction of antioxidant defense in treated animals compared to the control rats.


Assuntos
Antioxidantes/química , Colestanonas/farmacologia , Diabetes Mellitus Experimental , Giberelinas/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Animais , Masculino , Reguladores de Crescimento de Plantas/farmacologia , Ratos , Ratos Wistar
8.
J Toxicol Sci ; 33(1): 25-30, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18303181

RESUMO

Carbendazim is a systemic broad-spectrum fungicide controlling a wide range of pathogens. It is also used as a preservative in paint, papermaking and leather industry, and as a preservative of fruits. In the present study, low dose intracellular effect of carbendazim was investigated employing 5, 10, 25 and 50 mM of the compound administered to male rats intradermally. Blood and liver of each animal was collected 6 hrs later to analyze serum and tissue enzyme activities, tissue lipid peroxidation and hematological and biochemical parameters. The experimental results of low dosage carbendazim use indicated augmentation of investigated parameters. However, the higher dosage of carbendazim use resulted in renormalization of investigated parameters to control levels or to values below control, providing a U-shaped hormesis type dose-response profile. Histopathological sections revealed portal vein congestion, mononuclear cell infiltration and hydropic degeneration of the liver tissue. These results indicated that carbendazim even at low dose exhibited toxicity, affected the liver and also caused specific changes in hematological and biochemical parameters in the rat.


Assuntos
Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Benzimidazóis/toxicidade , Carbamatos/toxicidade , Fungicidas Industriais/toxicidade , Fígado/efeitos dos fármacos , Alanina Transaminase/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Colesterol/sangue , Contagem de Eritrócitos , Hemoglobinas/análise , Contagem de Leucócitos , Fígado/metabolismo , Fígado/patologia , Masculino , Malondialdeído/metabolismo , Ratos , Ratos Wistar
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