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1.
Clin Exp Immunol ; 176(2): 283-90, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24387292

RESUMO

Toll-like receptors (TLRs) recognize pathogen-associated molecular patterns and results in innate immune system activation that results in elicitation of the adaptive immune response. One crucial modulator of the adaptive immune response is CD40. However, whether these molecules influence each other's expression and functions is not known. Therefore, we examined the effects of TLRs on CD40 expression on macrophages, the host cell for the protozoan parasite Leishmania major. While polyinosinic-polycytidylic acid [poly (I:C)], a TLR-3 ligand, lipopolysaccharide (LPS), a TLR-4 ligand, imiquimod, a TLR-7/8 ligand and cytosine-phosphate-guanosine (CpG), a TLR-9 ligand, were shown to enhance CD40 expression, CD40 stimulation enhanced only TLR-9 expression. Therefore, we tested the synergism between CD40 and CpG in anti-leishmanial immune response. In Leishmania-infected macrophages, CpG was found to reduce CD40-induced extracellular stress-regulated kinase (ERK)1/2 activation; with the exception of interleukin (IL)-10, these ligands had differential effects on CD40-induced IL-1α, IL-6 and IL-12 production. CpG significantly enhanced the anti-leishmanial function of CD40 with differential effects on IL-4, IL-10 and interferon (IFN)-γ production in susceptible BALB/c mice. Thus, we report the first systematic study on CD40-TLR cross-talk that regulated the experimental L. major infection.


Assuntos
Antígenos CD40/imunologia , Expressão Gênica/imunologia , Leishmania major/imunologia , Macrófagos/imunologia , Receptor Toll-Like 9/imunologia , Aminoquinolinas/imunologia , Aminoquinolinas/farmacologia , Animais , Western Blotting , Antígenos CD40/genética , Antígenos CD40/metabolismo , Células Cultivadas , MAP Quinases Reguladas por Sinal Extracelular/imunologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Citometria de Fluxo , Expressão Gênica/efeitos dos fármacos , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Interações Hospedeiro-Patógeno/imunologia , Imiquimode , Leishmania major/fisiologia , Lipopolissacarídeos/imunologia , Lipopolissacarídeos/farmacologia , Macrófagos/metabolismo , Macrófagos/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Oligodesoxirribonucleotídeos/imunologia , Oligodesoxirribonucleotídeos/farmacologia , Fosforilação/efeitos dos fármacos , Fosforilação/imunologia , Receptor Cross-Talk/efeitos dos fármacos , Receptor Cross-Talk/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Receptor Toll-Like 9/genética , Receptor Toll-Like 9/metabolismo , Receptores Toll-Like/genética , Receptores Toll-Like/imunologia , Receptores Toll-Like/metabolismo
2.
Artigo em Inglês | MEDLINE | ID: mdl-38906125

RESUMO

Purpose/Objective Small-field measurement poses challenges. Although many high-resolution detectors are commercially available, the EPID for small-field dosimetry remains underexplored. This study aimed to evaluate the performance of EPID for small-field measurements and to derive tailored correction factors for precise small-field dosimetry verification. Material/Methods Six high-resolution radiation detectors, including W2 and W1 plastic scintillators, Edge-detector, microSilicon, microDiamond and EPID were utilized. The output factors, depth doses and profiles, were measured for various beam energies (6 MV-FF, 6 MV-FFF, 10 MV-FF, and 10 MV-FFF) and field sizes (10 x 10 cm2, 5 x 5 cm2, 4 x 4 cm2, 3 x 3 cm2, 2 x 2 cm2, 1 x 1 cm2, 0.5 x 0.5 cm2) using a Varian Truebeam linear accelerator. During measurements, acrylic plates of appropriate depth were placed on the EPID, while a 3D water tank was used with five-point detectors. EPID measured data were compared with W2 plastic scintillator and measurements from other high-resolution detectors. The analysis included percentage deviations in output factors, differences in percentage for PDD and for the profiles, FWHM, maximum difference in the flat region, penumbra, and 1D gamma were analyzed. The output factor and depth dose ratios were fitted using exponential functions and fractional polynomial fitting in STATA 16.2, with W2 scintillator as reference, and corresponding formulae were obtained. The established correction factors were validated using two Truebeam machines. Results When comparing EPID and W2-PSD across all field-sizes and energies, the deviation for output factors ranged from 1% to 15%. Depth doses, the percentage difference beyond dmax ranged from 1% to 19%. For profiles, maximum of 4% was observed in the 100% - 80% region. The correction factor formulae were validated with two independent EPIDs and closely matched within 3%. Conclusion EPID can effectively serve as small-field dosimetry verification tool with appropriate correction factors.

3.
Clin Exp Immunol ; 172(3): 403-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23600828

RESUMO

Two different Toll-like receptors (TLRs) have been shown to play a role in host responses to Leishmania infection. TLR-2 is involved in parasite survival in macrophages upon activation by lipophosphoglycan (LPG), a virulence factor expressed by Leishmania. In contrast, activation of TLR-9 has been shown to promote a host-protective response. However, whether there is a relationship between the interaction of LPG and TLR-2, on one hand, with the effect of TLR-9, on the other hand, remains unknown. In this study, we report that in-vitro infection of macrophages with a L. major parasite with high expression levels of LPG results in decreased TLR-9 expression compared to infection with a L. major parasite with lower expression levels of LPG. Addition of anti-LPG as well as anti-TLR-2 antibodies prevents this reduction of TLR-9 expression. Also, the addition of purified LPG to macrophages results in a decrease of TLR-9 expression, which is shown to be mediated by transforming growth factor (TGF)-ß and interleukin (IL)-10. Finally, in-vitro treatment of macrophages with anti-LPG and/or anti-TLR-2 antibodies before infection reduces the number of amastigotes in macrophages and co-treatment of mice with anti-TLR-2 antibodies and cytosine-phosphate-guanosine (CpG) reduces footpad swelling and parasite load in the draining lymph nodes, accompanied by an interferon (IFN)-γ-predominant T cell response. Thus, for the first time, we show how interactions between LPG and TLR-2 reduce anti-leishmanial responses via cytokine-mediated decrease of TLR-9 expression.


Assuntos
Glicoesfingolipídeos/imunologia , Leishmania major/imunologia , Leishmania major/patogenicidade , Receptor 2 Toll-Like/metabolismo , Receptor Toll-Like 9/metabolismo , Animais , Ilhas de CpG/imunologia , Expressão Gênica , Glicoesfingolipídeos/genética , Interações Hospedeiro-Parasita/genética , Interações Hospedeiro-Parasita/imunologia , Tolerância Imunológica , Interleucina-10/genética , Interleucina-10/metabolismo , Leishmania major/genética , Leishmaniose Cutânea/genética , Leishmaniose Cutânea/imunologia , Leishmaniose Cutânea/parasitologia , Leishmaniose Cutânea/terapia , Ativação de Macrófagos , Macrófagos/imunologia , Macrófagos/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Receptor 2 Toll-Like/antagonistas & inibidores , Receptor 2 Toll-Like/genética , Receptor Toll-Like 9/genética , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Virulência/imunologia
4.
Appl Biochem Biotechnol ; 183(3): 980-992, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28497373

RESUMO

Lignin is a versatile plant metabolite challenging high-end industrial applications of several plant products including jute. Application of developmental mutant in regulation of lignification in jute may open up door for much awaited jute based diversified products. In the present study, a novel dark jute (Corchorus olitorius L.) mutant with low lignin (7.23%) in phloem fibre being compared to wild-type JRO 204 (13.7%) was identified and characterised. Unique morphological features including undulated stem, petiole and leaf vein distinguished the mutant in gamma ray irradiated mutant population. Histological and biochemical analysis revealed reduced lignification of phloem fibre cells of the plant. RT-PCR analysis demonstrated temporal transcriptional regulation of CCoAMT1 gene in the mutant. The mutant was found an extremely useful model to study phloem fibre developmental biology in the crop besides acting as a donor genetic stock for low lignin containing jute fibre in dark jute improvement programme.


Assuntos
Corchorus/genética , Corchorus/metabolismo , Lignina/metabolismo , Mutação , Floema/metabolismo , Corchorus/citologia , Corchorus/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Genes de Plantas/genética , Lignina/biossíntese , Floema/citologia , Floema/genética , Floema/crescimento & desenvolvimento , Caules de Planta/crescimento & desenvolvimento , Transcrição Gênica
5.
Biosystems ; 83(1): 38-50, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16236422

RESUMO

Plant promoters have not yet been thoroughly analyzed in terms of their structural and sequence dependent properties like curvature, periodicity and information content and our present study is an attempt in that direction. Results were compared with E. coli and yeast data to get some insight into the promoter organization. Promoters having the TATA box (TATA(+)) and those lacking the same (TATA(-)) were also analyzed separately. It was found that plant promoters have marked differences for all these properties when compared to E. coli and yeast. Bias for A+T was observed in promoters of all the three groups. Compared to E. coli and yeast, plant promoters showed intermediate values for A+T content as well as curvature. Analysis showed that curvature of core promoters is more pronounced than non-promoters. Information theoretic analysis of plant promoters reveal high information content at certain consensus regions such as -30 (TATA box) and +1 transcription start site (TSS); and have moderate values at other positions as well. This factor was taken into account while developing weight matrices. For certain threshold values, these weight matrices could pick up all true positives, and reduce false positives to a great extent in a test set. A new multi-parameterized prediction strategy has been proposed that uses a combination of sequence composition, curvature and position weight matrices for identification of plant promoters. This strategy was tested and validated with experimentally known promoter sequences. Our study is novel in using in silico approaches to study the sequence dependent properties of plant RNA Pol-II promoters and their prediction, and important as there is no dedicated promoter search tool for plants.


Assuntos
Biologia Computacional , Regiões Promotoras Genéticas/genética , RNA Polimerase II/genética , RNA de Plantas/genética , Sequência de Bases , Bases de Dados Genéticas , Entropia
6.
3 Biotech ; 6(1): 100, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28330170

RESUMO

Tossa jute is an important natural fiber crop of Southeast Asian countries including India, Bangladesh, China, Thailand, Myanmar etc. Traditional industrial application of jute fiber is limited to the packaging products like hessians, sacks, etc. and the fiber found unsuitable for textile industries largely due to significantly high lignin content. Therefore, understanding genetic factors underlying lignin biosynthesis in tossa jute holds promise for jute based product diversification. The major limiting factor in undertaking such study is unavailability of efficient protocol for RNA extraction at secondary growth active stage of tossa jute. Here we report a simplified, swift and cost effective protocol for isolating fairly good quality RNA from bark tissue of 65-days-old field grown tossa jute plant with active secondary growth. The purity, concentration and integrity of extracted RNA ascertained. To confirm downstream amenability, isolated RNA samples were reverse transcribed and PCR analysis done by using CCoAMT1 primer. Results established that method of RNA extraction presented here is an improvement over the other methods, particularly for bark tissue of field grown tossa jute at advance developmental stage. Therefore, present study will enhance our ability to understand expression pattern of fiber formation and maturation related genes in mature bark tissue that holds key for much talked genetic manipulation of fiber quality via lignin optimisation in the crop.

7.
J Environ Qual ; 34(2): 635-43, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15758116

RESUMO

Land application has become a widely applied method for treating wastewater. However, it is not always clear which soil-plant systems should be used, or why. The objectives of our study were to determine if four contrasting soils, from which the pasture is regularly cut and removed, varied in their ability to assimilate nutrients from secondary-treated domestic effluent under high hydraulic loadings, in comparison with unirrigated, fertilized pasture. Grassed intact soil cores (500 mm in diameter by 700 mm in depth) were irrigated (50 mm wk(-1)) with secondary-treated domestic effluent for two years. Soils included a well-drained Allophanic Soil (Typic Hapludand), a poorly drained Gley Soil (Typic Endoaquept), a well-drained Pumice Soil formed from rhyolitic tephra (Typic Udivitrand), and a well-drained Recent Soil formed in a sand dune (Typic Udipsamment). Effluent-irrigated soils received between 746 and 815 kg N ha(-1) and 283 and 331 kg P ha(-1) over two years of irrigation, and unirrigated treatments received 200 kg N ha(-1) and 100 kg P ha(-1) of dissolved inorganic fertilizer over the same period. Applying effluent significantly increased plant uptake of N and P from all soil types. For the effluent-irrigated soils plant N uptake ranged from 186 to 437 kg N ha(-1) yr(-1), while plant P uptake ranged from 40 to 88 kg P ha(-1) yr(-1) for the effluent-irrigated soils. Applying effluent significantly increased N leaching losses from Gley and Recent Soils, and after two years ranged from 17 to 184 kg N ha(-1) depending on soil type. Effluent irrigation only increased P leaching from the Gley Soil. All P leaching losses were less than 49 kg P ha(-1) after two years. The N and P leached from effluent treatments were mainly in organic form (69-87% organic N and 35-65% unreactive P). Greater N and P leaching losses from the irrigated Gley Soil were attributed to preferential flow that reduced contact between the effluent and the soil matrix. Increased N leaching from the Recent Soil was the result of increased leaching of native soil organic N due to the higher hydraulic loading from the effluent irrigation.


Assuntos
Nitrogênio/farmacocinética , Fósforo/farmacocinética , Poaceae/química , Poluentes do Solo/farmacocinética , Solo , Eliminação de Resíduos Líquidos/métodos , Poluentes da Água/farmacocinética , Agricultura , Monitoramento Ambiental , Nitrogênio/análise , Permeabilidade , Fósforo/análise , Poluentes do Solo/análise , Solubilidade , Movimentos da Água , Poluentes da Água/análise
8.
Toxicol Int ; 18(2): 160-2, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21976823

RESUMO

Ethinyl oestradiol (EO) is the most commonly used as a component of oral contraceptive and hormonal replacement therapy (HRT) in women. However, its excessive and prolonged use may cause cytotoxicity, including cancer of many organs. Hence, the present study was performed to produce the experimental hepatotoxicity in female albino rats. EO was administered to different groups of rats, respectively @ 250, 500 and 750 µg/kg body weight, orally, weekly for 16 and 20 weeks. One group of rats was administered with saline alone to serve as control. The rats were sacrificed after their respective experimental periods, and the livers were collected and preserved in 10% buffered formalin. Later on, the histopathological study of liver tissues was done. On the 17(th) week, the hepatic tissues showed severe congestion, focal areas of hemorrhage, extreme vacuolation of cytoplasm, distended sinusoids with dilated central veins. Degeneration and necrosis of hepatocytes as evidenced by increased cytoplasmic granularity, and dissolution of nuclear materials were seen. On the 21(st) weeks, these changes were extremely severe and quite conspicuous. Distinct fibrosis was also noticed. EO caused hepatotoxicity, the extent and severity of which were dose and time dependent, indicating that this drug at higher dose after prolonged duration (500 or 750 µg/kg, orally, weekly for 20 weeks) may cause the standard experimental hepatotoxicity in rats.

11.
Curr Microbiol ; 55(2): 135-41, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17647080

RESUMO

One hundred fifty-five isolates of Bipolaris sorokiniana of wheat were studied for their morphopathological characterization. These isolates were grouped in five categories--black, brown/dull black, gray cottony growth, dull white/greenish black, and white--on the basis of their growth pattern. The frequency of the black suppressed type was maximum (45.63%), whereas the white isolate displayed lowest frequency (6.96%) in the natural population. Twenty RAPD (random amplified polymorphic DNA) primers were used to observe the variability among the identified groups of B. sorokininana. From each group, eight random isolates were investigated. A total of 143 bands were amplified, out of which 107 (74.83%) were polymorphic and 36 (25.17%) were monomorphic. On an average, the total numbers of bands generated per primer were 7.15, of which 5.35 and 1.80 were polymorphic and monomorphic, respectively. Dendrograms based on molecular polymorphism unveiled a considerable amount of diversity among the isolates. Specific DNA bands were identified for selected isolates. The distinct markers appeared to be potential enough to be employed as genetic fingerprints for future strain identification and classification. The study indicated that the RAPD primers provide an easy, rapid, and simple technique for the preliminary assessment of genetic diversity among the fungal isolates.


Assuntos
Ascomicetos/genética , Ascomicetos/patogenicidade , Doenças das Plantas/microbiologia , Triticum/microbiologia , Ascomicetos/isolamento & purificação , Sequência de Bases , DNA Fúngico/genética , Genes Fúngicos , Marcadores Genéticos , Filogenia , Técnica de Amplificação ao Acaso de DNA Polimórfico , Virulência/genética
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