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1.
Sci Rep ; 10(1): 3079, 2020 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-32080285

RESUMO

The ladybird beetle, Harmonia sedecimnotata (F.) was studied in biology, life table, consumption rates, molecular characterization, and field evaluation. The net reproductive rate (R0), based on the age-stage and two-sex life table, was 43.2 eggs/individual. The female adults lived longer (68.1 d) than the male adults (62.9 d). The rate of consumption increased with progress in each stage of development. Compared to the other larval stages of the predator, the fourth stadium consumed most quantities of Aphis gossypii Glover nymphs (Hemiptera: Aphididae) (200.4). Both female (2214.6) and male (1792.4) consumed more prey (nymphs) than larvae. The net rate of consumption was 1458.92 nymphs of melon aphids. There was no variation in the sequences of the two nucleotides out of 583 bp, H sedecimnotata China (EU392410) and India (MG720024). Our investigations demonstrated that inoculative release of 30 or 40 or 50 adults per 100 m2 attained high reduction of aphids (>90%). Thus, it may be recommended the release rate of 40 adults per 100 m2 to suppress the eggplant aphid population. H. sedecimnotata is therefore one of the most promising biological control agents for cotton aphids that can be achieved for instant control through an inoculative release of adults.


Assuntos
Afídeos/fisiologia , Besouros/fisiologia , Tábuas de Vida , Comportamento Predatório/fisiologia , Animais , Feminino , Fertilidade , Larva/fisiologia , Longevidade/fisiologia , Masculino , Filogenia , Dinâmica Populacional , Estações do Ano , Solanum melongena/parasitologia
2.
Eur J Clin Microbiol Infect Dis ; 36(11): 2273-2279, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28756561

RESUMO

In India, dengue endemic areas overlap with chikungunya-affected areas and both the viruses are transmitted by same vector, Aedes aegypti - thereby increasing opportunity of co-infection by both viruses. Present study was carried out to understand the DENV-CHIKV infection dynamics during recent outbreaks in eastern India (West Bengal state) and its implication on disease manifestations. Blood was collected from 326 symptomatic febrile patients. Patients' serum was subjected to serological diagnosis for presence of anti-dengue-IgM, anti-chikungunya-IgM antibodies and dengue-NS1 antigen by ELISA. Viral RNA was extracted, and presence of dengue virus (DENV) and chikungunya virus (CHIKV) genome, their viral load (VL), and serotype among infected patients' plasma was determined by real-time qRT-PCR. Statistical analysis was performed by using EPI INFO software. DENV and CHIKV were detected in 54% and 33% of symptomatic patients respectively, among whom 23% were harboring both viruses. WHO classified warning signs were detected among 64% DENV patients and 61% DENV-CHIKV double-infected patients. Patients with warning signs always had much higher DEN VL than those without warning signs. Hemorrhagic manifestation and abdominal pain was found in significantly higher frequency among patients with high dengue VL (>10,000 copies/ml). DENV2 was the most predominant serotype among monotypic dengue patients, whereas DENV2-DENV4 combination was most prevalent among patients infected with dual dengue serotypes. This study indicated that DENV-CHIKV double infection and high dengue VL contributed towards severe disease manifestations among infected patients. DENV2 and DENV2-DENV4 combination were the most prevalent serotype(s) found in current outbreak.


Assuntos
Febre de Chikungunya/epidemiologia , Vírus Chikungunya/imunologia , Coinfecção/virologia , Vírus da Dengue/classificação , Vírus da Dengue/imunologia , Dengue/epidemiologia , Adolescente , Adulto , Anticorpos Antivirais/sangue , Febre de Chikungunya/complicações , Febre de Chikungunya/virologia , Vírus Chikungunya/classificação , Criança , Pré-Escolar , Dengue/complicações , Dengue/virologia , Surtos de Doenças , Glicoproteínas/sangue , Humanos , Imunoglobulina M/sangue , Índia/epidemiologia , Lactente , Recém-Nascido , Sorogrupo , Proteínas não Estruturais Virais/sangue , Adulto Jovem
3.
Zootaxa ; 4263(2): 318-332, 2017 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-28609871

RESUMO

In this paper we resolve the taxonomic confusion related to Ahaetulla nasuta anomala (Annandale, 1906). On the basis of molecular and morphological data, we remove it from the synonymy of Ahaetulla nasuta (Lacépède, 1789) and reinstate it as a valid species-Ahaetulla anomala. This species is sexually dichromatic, males are green and females are brown in colour. Though the brown morph morphologically resembles Ahaetulla pulverulenta (Duméril, Bibron & Duméril, 1854) there are significant morphological and genetic differences between these two species. Additional information on taxonomy, natural history and distribution of the species is provided.


Assuntos
Colubridae , Animais , Feminino , Masculino
4.
J Genet Eng Biotechnol ; 15(1): 169-178, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30647653

RESUMO

Phosphorus is an essential element for all life forms. Phosphate solubilizing bacteria are capable of converting phosphate into a bioavailable form through solubilization and mineralization processes. Hence in the present study a phosphate solubilizing bacterium, PSB-37, was isolated from mangrove soil of the Mahanadi river delta using NBRIP-agar and NBRIP-BPB broth containing tricalcium phosphate as the phosphate source. Based on phenotypic and molecular characterization, the strain was identified as Serratia sp. The maximum phosphate solubilizing activity of the strain was determined to be 44.84 µg/ml, accompanied by a decrease in pH of the growth medium from 7.0 to 3.15. During phosphate solubilization, various organic acids, such as malic acid (237 mg/l), lactic acid (599.5 mg/l) and acetic acid (5.0 mg/l) were also detected in the broth culture through HPLC analysis. Acid phosphatase activity was determined by performing p-nitrophenyl phosphate assay (pNPP) of the bacterial broth culture. Optimum acid phosphatase activity was observed at 48 h of incubation (76.808 U/ml), temperature of 45 °C (77.87 U/ml), an agitation rate of 100 rpm (80.40 U/ml), pH 5.0 (80.66 U/ml) and with glucose as a original carbon source (80.6 U/ml) and ammonium sulphate as a original nitrogen source (80.92 U/ml). Characterization of the partially purified acid phosphatase showed maximum activity at pH 5.0 (85.6 U/ml), temperature of 45 °C (97.87 U/ml) and substrate concentration of 2.5 mg/ml (92.7 U/ml). Hence the present phosphate solubilizing and acid phosphatase production activity of the bacterium may have probable use for future industrial, agricultural and biotechnological application.

5.
J Genet Eng Biotechnol ; 15(1): 197-210, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30647656

RESUMO

Cellulose is an abundant natural biopolymer on earth, found as a major constituent of plant cell wall in lignocellulosic form. Unlike other compounds cellulose is not easily soluble in water hence enzymatic conversion of cellulose has become a key technology for biodegradation of lignocellulosic materials. Microorganisms such as aerobic bacteria, fungi, yeast and actinomycetes produce cellulase that degrade cellulose by hydrolysing the ß-1, 4-glycosidic linkages of cellulose. In contrast to aerobic bacteria, anaerobic bacteria lack the ability to effectively penetrate into the cellulosic material which leads to the development of complexed cellulase systems called cellulosome. Among the different environments, the sediments of mangrove forests are suitable for exploring cellulose degrading microorganisms because of continuous input of cellulosic carbon in the form of litter which then acts as a substrate for decomposition by microbe. Understanding the importance of cellulase, the present article overviews the diversity of cellulolytic microbes from different mangrove environments around the world. The molecular mechanism related to cellulase gene regulation, expression and various biotechnological application of cellulase is also discussed.

6.
Cell Death Differ ; 23(4): 707-22, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26494468

RESUMO

Mutation in the TP53 gene positively correlates with increased incidence of chemoresistance in different cancers. In this study, we investigated the mechanism of chemoresistance and epithelial-to-mesenchymal transition (EMT) in colorectal cancer involving the gain-of-function (GOF) mutant p53/ephrin-B2 signaling axis. Bioinformatic analysis of the NCI-60 data set and subsequent hub prediction identified EFNB2 as a possible GOF mutant p53 target gene, responsible for chemoresistance. We show that the mutant p53-NF-Y complex transcriptionally upregulates EFNB2 expression in response to DNA damage. Moreover, the acetylated form of mutant p53 protein is recruited on the EFNB2 promoter and positively regulates its expression in conjunction with coactivator p300. In vitro cell line and in vivo nude mice data show that EFNB2 silencing restores chemosensitivity in mutant p53-harboring tumors. In addition, we observed high expression of EFNB2 in patients having neoadjuvant non-responder colorectal carcinoma compared with those having responder version of the disease. In the course of deciphering the drug resistance mechanism, we also show that ephrin-B2 reverse signaling induces ABCG2 expression after drug treatment that involves JNK-c-Jun signaling in mutant p53 cells. Moreover, 5-fluorouracil-induced ephrin-B2 reverse signaling promotes tumorigenesis through the Src-ERK pathway, and drives EMT via the Src-FAK pathway. We thus conclude that targeting ephrin-B2 might enhance the therapeutic potential of DNA-damaging chemotherapeutic agents in mutant p53-bearing human tumors.


Assuntos
Neoplasias Colorretais/metabolismo , Dano ao DNA , Resistencia a Medicamentos Antineoplásicos , Efrina-B2/metabolismo , Transição Epitelial-Mesenquimal , Animais , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Efrina-B2/genética , Feminino , Xenoenxertos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
7.
Rev Sci Instrum ; 84(6): 063702, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23822347

RESUMO

We discuss the design and operation of a confocal rheometer, formed by integrating an Anton Paar MCR301 stress-controlled rheometer with a Leica SP5 laser scanning confocal microscope. Combining two commercial instruments results in a system which is straightforward to assemble that preserves the performance of each component with virtually no impact on the precision of either device. The instruments are configured so that the microscope can acquire time-resolved, three-dimensional volumes of a sample whose bulk viscoelastic properties are being measured simultaneously. We describe several aspects of the design and, to demonstrate the system's capabilities, present the results of a few common measurements in the study of soft materials.


Assuntos
Colágeno/química , Microscopia Confocal/instrumentação , Reologia/instrumentação , Desenho de Equipamento , Multimerização Proteica , Estrutura Quaternária de Proteína
8.
J Hazard Mater ; 227-228: 219-26, 2012 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-22677051

RESUMO

A Gram-positive moderately halophilic Cr(VI) tolerant bacterial strain H4, isolated from saline mangrove soil, was identified as Vigribacillus sp. by biochemical characterization and 16S rRNA analysis. In LB medium, the strain could tolerate up to 1000 mg L(-1) Cr(VI) concentration and reduced 90.2 and 99.2% of 100 mg L(-1) Cr(VI) under optimized set of condition within 70 h in absence and presence of 6 wt.% NaCl, respectively. The fitting of time course reduction data to an exponential rate equation yielded the Cr(VI) reduction rate constants in the range (0.69-5.56)×10(-2)h(-1). Analyses of total chromium and bacterial cell associated with reduced product by AAS, SEM/EDS, TEM/SAED, FT-IR and UV-vis-DRS indicated the formation of about 35% of insoluble Cr(III) either as Cr(OH)(3) precipitate in nanometric size or immobilized on the bacterial cell surface while the remaining 65% of reduced chromium was present as soluble Cr(III) in the growth medium. Powder XRD analysis revealed the amorphous nature of the precipitated Cr(OH)(3). The high Cr(VI) reducing ability of the strain under saline condition suggests the Vigribacillus sp. as a new and efficient strain capable of remediating highly saline Cr(VI) polluted industrial effluents.


Assuntos
Cromo/metabolismo , Poluentes do Solo/metabolismo , Virgibacillus/metabolismo , Biodegradação Ambiental/efeitos dos fármacos , Cromo/toxicidade , Índia , Oxirredução , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Cloreto de Sódio/farmacologia , Poluentes do Solo/toxicidade , Virgibacillus/efeitos dos fármacos , Virgibacillus/genética , Virgibacillus/isolamento & purificação
9.
J Food Sci Technol ; 48(6): 740-4, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23572814

RESUMO

Buffalo milk standardized to solids-not-fat (SNF) to fat ratio of 1.4 was added separately with 0.1% (w/w) each of carrageenan, sodium alginate and carboxymethyl cellulose and then heated, cooled and coagulated to obtain chhana which was converted into sandesh by adding 1.5% (w/w) wheat flour and 25% (w/w) cane sugar followed by heating (40 min/kg chhana). The treated samples of sandesh were compared with control prepared similarly manner but without stabilizer. Addition of stabilizer decreased hardness, fracturability, adhesiveness, cohesiveness, gumminess and chewiness of sandesh and improved sensory body and texture, colour and appearance as well as overall acceptability of the product when compared with control. Textural and sensory properties of different samples of sandesh indicated that the product made by adding carrageenan proved best. Carrageenan at 0.1% produced better results in terms of textural and sensory profile of sandesh as compared to 0, 0.075 and 0.125% (w/w) of carrageenan.

10.
Ecotoxicology ; 20(1): 283-92, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21153054

RESUMO

Labeo rohita (rohu) fingerlings were exposed to different concentrations (0.001, 0.002 and 0.01 ppm) of phorate, an organophosphate pesticide; samplings were done at 24, 48, 72 and 96 h. The study was carried out to evaluate tissue specific genotoxic effects produced by phorate, on three different tissue systems and to assess DNA repair response in fish. Results of tissue specific DNA damage experiments showed low baseline damage in blood cells followed by gill and liver cells in control individuals whereas more DNA breaks were found in liver followed by gill and blood cells of treated individuals. Concentrations-dependent DNA damage showed a strong, linear and positive relationship (r(2) = >0.7) in all three tissues. Clear time-related increase in DNA damage was observed for all tissues exposed to all concentrations except in liver cells at 0.01 ppm, where the DNA damage declined significantly after 72 h. For the assessment of DNA repair response, fingerlings were first exposed to 0.01 ppm of phorate for 72 h and then transferred to pesticide free water. Tissue chosen for the repair experiment was liver. Samplings were done at 0, 3, 6, 12 and 24 h after the release of 72 h pesticide treated fishes into pesticide free water. Fishes showed a reduction in DNA breaks from 3 h onwards in pesticide free water and at 24 h returned to control level damage. The results indicate that phorate is a potential genotoxicant, comet assay can be used in DNA damage and repair analysis, response to pollutants in multicellular animals is often tissue specific.


Assuntos
Ensaio Cometa/métodos , Cyprinidae/genética , Dano ao DNA , Praguicidas/toxicidade , Forato/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Células Sanguíneas/efeitos dos fármacos , Células Sanguíneas/patologia , Reparo do DNA , Fígado/efeitos dos fármacos , Fígado/patologia
11.
Indian J Exp Biol ; 48(11): 1094-7, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21117448

RESUMO

A proximo-distal gradient of reduced glutathione (GSH), a non enzymatic antioxidant was observed in the original tails of the lizard, H. leschenaultii. In the regenerating tails, a gradual increase in the level of GSH was noted with tail elongation. In the newly regenerated tails also the level of GSH remained higher in the proximal part than the corresponding distal parts.


Assuntos
Glutationa/metabolismo , Lagartos/metabolismo , Cauda/metabolismo , Amputação Cirúrgica , Análise de Variância , Animais , Lagartos/fisiologia , Lagartos/cirurgia , Regeneração , Cauda/fisiologia , Cauda/cirurgia , Fatores de Tempo
12.
Aliment Pharmacol Ther ; 32(6): 795-800, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20629975

RESUMO

BACKGROUND: The pathogenesis of gastro-oesophageal reflux disease includes increased acid reflux, reduced salivation and impaired peristalsis. This may depend upon the height of acid wave and magnitude of oesophageal mucosal exposure. Interestingly, the effect of site of acid infusion upon salivary secretion and heartburn has not been examined in any detail. AIM: To examine whether acid infusion in the upper oesophagus may cause increased salivation and heartburn as compared with acid infusion in the lower oesophagus. METHODS: Twelve healthy male subjects (mean age 30) received infusions of HCl, citric acid and acetic acid at 10 and 20 cm above the lower oesophageal sphincter (LES) for fixed time periods. Parotid saliva collected periodically and heartburn severity scored using standardized scale. Standard statistical methods (paired t-tests, analysis of variance) were used to determine the significance of results. RESULTS: Acid infusion in the upper oesophagus increased parotid flow rate as compared with that in the lower oesophagus (P < 0.05). Likewise, there was a significantly increased heartburn score at 20 cm as well as 10 cm above LES (P < 0.05) as compared with that in the stomach. CONCLUSION: These data suggest a significant increase in salivation and heartburn in response to acid infusion in the upper vs. lower part of the oesophagus.


Assuntos
Esôfago/fisiologia , Refluxo Gastroesofágico/fisiopatologia , Azia/induzido quimicamente , Ácido Clorídrico/administração & dosagem , Peristaltismo/fisiologia , Salivação/fisiologia , Adulto , Esôfago/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Masculino , Pessoa de Meia-Idade , Peristaltismo/efeitos dos fármacos , Salivação/efeitos dos fármacos , Estatística como Assunto , Adulto Jovem
13.
J Adv Pharm Technol Res ; 1(4): 419-22, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22247883

RESUMO

In this study, the antibacterial activity of crude (aqueous and alcoholic) extracts of the bark and leaf of Croton roxburghii Balak. (Euphorbiaceae) was tested against enteric pathogens causing urinary tract infection (UTI) using the agar cup method, minimum inhibitory concentration (MIC), time kill kinetics and synergy study. The ethanol extract exhibited a significant and broad spectrum of inhibition as compared to the aqueous extract of both the bark and leaf. The highest antibacterial activity was observed against Staphylococcus aureus followed by enteropathogenic and enterotoxigenic Escherichia coli. The diameter of inhibition zones varied from 10 to 18 mm for both aqueous and alcoholic extracts. The MIC value ranged from 356 to 625 µg/ml. This could justify the traditional use of this plant in dysentery and other infections.

14.
J Environ Pathol Toxicol Oncol ; 28(3): 231-4, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19888910

RESUMO

During microbial or mammalian cell metabolism, TNT (2,4,6-tinitrotoluene) is reduced to 2Am-DNT (2-amino-4,6-dinitrotoluene), 4Am-DNT, or 2,4-diamino-NT (2,4-diaminonitrotoluelne) depending on the specific organism. The metabolite 2Am-DNT is the most common of the TBT biotransformation pathways in bacterial and fungal species studied to date. in the mammalian liver cells, TNT is metabolized to 2Am-DNT by the P450 enzyme system. Apoptosis is rapidly emerging as a relevant endpoint for detecting low-dose toxin exposure. We report in this study that 2Am-DNT treatment of mammalian cells causes cell death by apoptosis. Cell death was assayed by the Trypan Blue method. Apoptotic changes, such as DNA break down, were detected in treated cells by the production of a dark-brown DAB (diaminobenzidine) signal using the Fragel Klenow DNA fragment detection system, by immunohistochemical techniques with fluorescence microscopy, and by using a microplate reader for a single-stranded DNA binding assay. All of these results showed that 2am-DNT is toxic to mammalian cells and induces apoptosis.


Assuntos
Compostos de Anilina/toxicidade , Apoptose/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA , DNA de Cadeia Simples/efeitos dos fármacos , DNA de Cadeia Simples/metabolismo , Feminino , Humanos , Marcação In Situ das Extremidades Cortadas , Microscopia de Fluorescência , Azul Tripano/metabolismo
15.
Vet Res Commun ; 33(7): 771-80, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19466575

RESUMO

The present study involves the use of RAPD-PCR to evaluate the genotoxic effects of furadan in the DNA of Labeo rohita (rohu) fingerlings. Rohu fingerlings were exposed to 0.02 ppm of furadan for a total period of 96 h and samplings were done at 24, 48, 72 and 96 h. RAPD - PCR were carried out with the blood and liver DNA samples of both control and treated groups at each of the four sampling hours. A total of six selected RAPD primers were used for PCR amplification. Template stability has been taken as the measure of DNA damage caused by pesticide. The results obtained showed no significant difference in the template stability in the blood DNA of furadan treated groups at any of the four sampling hours; however, the liver DNA were able to show significant difference at 48 and 96 hours of treatment.


Assuntos
Cyprinidae/genética , Dano ao DNA/efeitos dos fármacos , Animais , Carbofurano/toxicidade , DNA/sangue , DNA/genética , Primers do DNA , Amplificação de Genes , Mutagênicos/toxicidade , Óperon/genética , Praguicidas/toxicidade , Técnica de Amplificação ao Acaso de DNA Polimórfico/métodos
16.
Environ Toxicol Pharmacol ; 25(2): 144-7, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21783850

RESUMO

The dechlorination of PCB, specifically the noncoplanar congener PCB 153, has been observed in the presence of a crude nitrate reductase extract from Medicago sativa leaves. These observations were further confirmed using a commercially available and pure nitrate reductase from Zea mays. The presence of nitrate reductase increased PCB 153 dechlorination. Then, the addition of molybdenum, the enzyme's cofactor, enhanced dechlorination of the environmental contaminant. The ability of plant nitrate reductase to dechlorinate PCB is a new observation.

17.
Verh Dtsch Ges Pathol ; 91: 286-93, 2007.
Artigo em Alemão | MEDLINE | ID: mdl-18314626

RESUMO

GIPC is highly expressed in human pancreatic adenocarcinoma and is a central protein for the stability of IGF-1R in pancreatic adenocarcinoma cell lines (15). The goal of this study was to prove the importance of GIPC in vivo and to evaluate possible therapeutic strategies that target this protein and its PDZ domain. In vivo effects of GIPC knockout were studied after lentiviral transduction of luciferase-expressing MiaPaCa2 pancreatic cancer cells with shRNA against GIPC; growth characteristics were monitored with bioluminiscence. Knockdown of GIPC led to a significant inhibition of pancreatic tumor cell growth in vivo in different mouse models. To test a possible therapeutic approach, the PDZ domain of GIPC was targeted by a short peptide composed of the amino acid sequence PSQSSSEA. This octapeptide was designed based on the C-terminal binding motif of GAIP. Targeting GIPC with this peptide inhibited the association between IGF-1R and GIPC. The subsequent downregulation of IGF-1R decreased proliferation in vitro and in vivo. In conclusion, our findings suggest that targeting GIPC and its PDZ domain-mediated interaction with the tyrosine kinase receptor IGF-1R could be a promising new treatment option for pancreatic cancer.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/deficiência , Proteínas Adaptadoras de Transdução de Sinal/genética , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Adenocarcinoma/patologia , Sequência de Aminoácidos , Sequência de Bases , Deleção de Genes , Humanos , Dados de Sequência Molecular , Oligopeptídeos/síntese química , Oligopeptídeos/química , Oligopeptídeos/uso terapêutico , Neoplasias Pancreáticas/patologia , RNA Neoplásico/genética , RNA Interferente Pequeno/genética
19.
Int J Toxicol ; 25(5): 341-7, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16940006

RESUMO

Polychlorinated biphenyls (PCBs) are among the most widespread and persistent pollutants in the global environment. Coplanar and noncoplanar PCBs have been shown to cause congener-specific apoptosis mediated neurotoxicity in rats. Very few, if any, such studies have been reported on human renal cell toxicity. The authors report here caspase-dependent or caspase-independent renal toxicity, as measured by apoptotic death induced by PCBs, depending on the planarity of congeners PCB-77 (coplanar) and PCB-153 (noncoplanar) in human kidney cells (HK2) in vitro. The authors have combined morphological and biological techniques to discover the relevance of apoptosis in renal proximal tubule cell death induced by these two PCB congeners. Treatment with both PCB congeners caused accelerated apoptosis in a time- and concentration-dependent manner. Based on our findings using human kidney (HK2) cells, there was more apoptosis-mediated loss of cell viability by non-ortho-substituted PCB-77 when compared to PCB-153. A significant increase of caspase-3 expression through immunoblot studies showed the involvement of apoptosis by PCB-77 compared to none by PCB-153. The broad-spectrum caspase inhibitor z-VAD-fmk showed increased cell death when treated by PCB-153, but not by PCB-77, confirming that caspase inhibitor induced a switch in the mode of cell death. It is reasonable to assume that apoptotic cell death in the renal proximal tubule cells treated by PCBs may have both caspase-dependent and caspase-independent pathways.


Assuntos
Apoptose/efeitos dos fármacos , Bifenilos Policlorados/toxicidade , Clorometilcetonas de Aminoácidos/farmacologia , Caspase 3/metabolismo , Inibidores de Caspase , Linhagem Celular , Fragmentação do DNA , Humanos , Rim/citologia , Dose Letal Mediana
20.
Indian J Exp Biol ; 44(2): 123-7, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16480178

RESUMO

The study was designed to examine the binding of diclofenac sodium with bovine serum albumin (BSA) at different temperatures (20 degrees, 30 degrees and 40 degrees C), pH (6.4, 7.4 and 8.4) and ionic strengths (micro = 0.1, 0.2 and 0.3) by means of equilibrium dialysis method. The concentration of diclofenac sodium was maintained at wider range from 15 to 900 micromole/l and BSA concentration was maintained at 61.5 micromole/l. The data obtained were interpreted by nonlinear regression method using Graphpad prism software. The analysis showed that the interaction between diclofenac sodium with BSA results in two-site saturable binding. A decrease in association constant was observed with increasing temperature. The average standard free energy change (deltaGdegrees) value was -7.07 (site I) and -4.2 (site II) Kcal/mol. The standard enthalpy change (deltaHdegrees) and the standard entropy change (deltaSdegrees) were -7.8 Kcal/mole, -2.35 cal/mole (site I) and -7.4 Kcal/mole, -10.5 cal/mole (site II), respectively. The negative enthalpy change suggested the binding between diclofenac sodium and the binding sites of BSA were spontaneous and exothermic. The negative value of deltaHdegrees and deltaSdegrees indicated hydrogen bonding and van der Waal's force was the major mechanism for diclofenac sodium and BSA interaction. Increase in pH and ionic strength also caused decrease in association constant of diclofenac sodium and BSA binding.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Diclofenaco/farmacologia , Soroalbumina Bovina/metabolismo , Animais , Bovinos , Diálise/métodos , Concentração de Íons de Hidrogênio , Concentração Osmolar , Ligação Proteica/efeitos dos fármacos , Termodinâmica
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