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1.
J Biosci ; 452020.
Artigo em Inglês | MEDLINE | ID: mdl-32020913

RESUMO

High-yielding Indian cotton varieties are not amenable for regeneration and transformation because they are recalcitrant in nature. In this work, we have developed Narasimha (NA1325) cotton variety by introducing three Cry genes driven by three different promoters conferring insect resistance. The meristematic region of embryo axis explants were infected and co-cultivated with Agrobacterium tumefacience (LBA4404) harbouring pMDC100 vector with three Cry gene cassettes (alpha-globulin : Cry2Ab, DECaMV35s : Cry1F and nodulin : Cry1Ac) with Npt II as a selectable marker gene. Out of 1010 embryo axes explants infected, 121 (T0) regenerated under two rounds of kanamycin selectionmedium.About 2551T1 seedswere collected from111T0 plants and these seeds screened again with kanamycin at seedling stage. The transgenic plants were characterized by PCR, real time quantitative PCR, lateral flow strip protein assay and insect bioassay. Out of 145 kanamycin resistant plants (T1), twelve showed amplification of all four transgenes: Npt II, Cry2Ab, Cry1F and Cry1Ac through PCR with expected amplicons as 395, 870, 840 and 618 bp, respectively. Further, lateral flow strip test revealed Cry1F and Cry1Ac proteins accumulated in 12 plants, whereas Cry2Ab protein was detected in eight only. The transcripts of all three Cry genes were accumulated significantly higher in transgenic plants at T2 generation. The transgenic lines showed effective resistance againstHelicoverpa armigera and Spodoptera litura larvae. The T2 line L-3 exhibited highest percentage of insect mortality, in which transcripts of all cry genes were accumulated higher than other plants. The transgenic cotton plants carrying triple Cry genes could be an excellent germplasmresource for the breeders for introgressions.


Assuntos
Agrobacterium tumefaciens/metabolismo , Proteínas de Bactérias/genética , Gossypium/genética , Gossypium/metabolismo , Larva/virologia , Nucleopoliedrovírus/patogenicidade , Plantas Geneticamente Modificadas/genética , Animais , Proteínas de Insetos , Receptores de Superfície Celular , Transformação Genética , Transgenes
2.
Nutr Neurosci ; 21(9): 648-656, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28569623

RESUMO

BACKGROUND: Obesity and Type 2 Diabetes (T2D) are chronic nutrient-related disorders that occur together and pose a grave burden to society. They are among the most common causes of ageing and death. Obesity and T2D per se accelerate ageing albeit the underlying mechanisms are unclear yet. Also, it is not clear whether or not superimposing T2D on obesity accelerates ageing. Present study validated the hypothesis, 'super-imposing T2D on obesity accelerates ageing' in WNIN/Gr-Ob, the impaired glucose tolerant, obese rat as the model and evaluated probable underlying mechanisms. OBJECTIVES: To estimate the survival analysis of WNIN/Gr-Ob rats induced with T2D. To determine the extent of DNA damage and oxidative stress in the brain, the master controller of the body, in WNIN/Gr-Ob rats with/without high sucrose induced T2D/aggravation of insulin resistance (IR) after 3 and 6 months of feeding. METHODS: T2D was induced/IR was aggravated by feeding high sucrose diet (HSD) to 9-10 weeks old, male WNIN/Gr-Ob rats. Survival percentage was determined statistically by Kaplan-Meier estimator. Neuronal DNA damage was quantified by the Comet assay while the oxidative stress and antioxidant status were evaluated from the levels of malonaldialdehyde, reduced glutathione, and superoxide dismutase (SOD) activity. RESULTS AND DISCUSSION: HSD feeding decreased longevity of WNIN/Gr-Ob rats and was associated with significantly higher total neuronal DNA damage after three months of feeding but not later. In line with this was the increased neuronal oxidative stress (lipid peroxidation) and decreased antioxidant status (reduced glutathione and SOD activity) in HSD than Starch-based diet (SBD) fed rats. The results suggest that HSD feeding decreased the longevity of WNIN/Gr-Ob obese rats probably by increasing oxidative stress and aggravating IR, a condition that precedes T2D.


Assuntos
Encéfalo/patologia , Dano ao DNA , Sacarose Alimentar/efeitos adversos , Longevidade , Estresse Oxidativo , Animais , Antioxidantes/metabolismo , Ensaio Cometa , Glutationa/metabolismo , Resistência à Insulina , Peroxidação de Lipídeos , Masculino , Malondialdeído/metabolismo , Neurônios/patologia , Obesidade , Ratos , Superóxido Dismutase/metabolismo
3.
Int J Biol Macromol ; 82: 823-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26526179

RESUMO

A novel extracellular alkali-thermostable xylanase was purified to an apparent homogeneity from the submerged fermented culture filtrate of Thielaviopsis basicola MTCC 1467, wherein, the fungus was fed with rice straw as prime carbon source. SDS-PAGE analysis of the xylanase showcased molecular weight of ∼ 32 kDa. This extracellular protein macromolecule had maximum xylanolytic activity at pH 5.5 and 60°C, and was stable in the range of pH 5.0-10.0 for 5 days retaining >70% activity. The enzyme was stable at 30-50°C for 5h retaining >85% activity and further by retaining 70% activity at 60°C for 2h. The enzyme deactivation constants (kd) were in range of 0.41-1.3. The kinetic experiments specified that the enzyme had Km and Vmax values of 1.447 ± 0.22 mg mL(-1) and 60.04 ± 1.25 IU mL(-1), respectively, for xylan. The purified xylanase was significantly inhibited by Cu(2+) and Zn(2+) (∼ 58%), whilst Ca(2+) and Na(+) ions displayed partial inhibition (<8%) Intriguingly, the K(+) and Mn(2+) ions enhanced the activity by about ∼ 10%. Both SDS and EDTA reduced its activity by ∼ 20%.


Assuntos
Ascomicetos , Endo-1,4-beta-Xilanases/química , Ascomicetos/enzimologia , Cromatografia por Troca Iônica , Endo-1,4-beta-Xilanases/antagonistas & inibidores , Endo-1,4-beta-Xilanases/isolamento & purificação , Inibidores Enzimáticos/farmacologia , Estabilidade Enzimática , Fermentação , Íons , Cinética , Metais/farmacologia , Temperatura , Termodinâmica
4.
Genet Test Mol Biomarkers ; 19(3): 128-32, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25565299

RESUMO

BACKGROUND: Polycystic ovaries and irregular menstruation/anovulation are important diagnostic criteria along with hyperandrogenism as per the Androgen Excess Society-2006 criteria for polycystic ovarian syndrome (PCOS). In the etiopathogenesis of PCOS, one of the candidate genes causing ovarian failure is the luteinizing hormone (LH) chorionic gonadotropin hormone receptor (LHCGR). Our aim was to study the association of LHCGR polymorphism (rs2293275) with PCOS in our study population. MATERIALS AND METHODS: Genetic case-control study from multiple gynecological centers from Hyderabad, a cosmopolitan city in South India. The study involved 204 women with PCOS and 204 healthy, sex-, and age-matched controls. Anthropometric and biochemical profiles were taken in a well-designed pro forma. Isolation of deoxyribonucleic acid (DNA) and genotype analysis were done for the entire study population using the polymerase chain reaction-restriction fragment length polymorphism method followed by 12% polyacrylamide gel electrophoresis. RESULTS: In this study, we have demonstrated an association between LHCGR (rs2293275) polymorphism and PCOS. The frequency of the G allele was 0.60 in PCOS and 0.49 in controls (odds ratio [OR] 1.531, confidence interval [CI] 1.16-2.01, and p-value=0.0026), which indicates that the G allele is associated with PCOS in our population. The GG genotype conferred a significant risk of developing PCOS (OR 3.36, CI 1.96-5.75, and p-value<0.0001). We found a significant association of the GG allele with body-mass index, waist to hip ratio, insulin resistance, LH, and LH/follicle-stimulating hormone (FSH) ratio in PCOS when compared with controls. The AA allele showed high basal FSH levels. CONCLUSIONS: This study suggests that LHCGR (rs2293275) polymorphism is associated with PCOS and could be used as a relevant molecular marker to identify women with the risk of developing PCOS in our population and may provide an understanding about the etiology of PCOS.


Assuntos
Síndrome do Ovário Policístico/genética , Receptores do LH/genética , Adolescente , Adulto , Estudos de Casos e Controles , Éxons , Feminino , Frequência do Gene , Predisposição Genética para Doença , Humanos , Polimorfismo de Nucleotídeo Único , Adulto Jovem
5.
Genet Test Mol Biomarkers ; 18(9): 605-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25083576

RESUMO

BACKGROUND: Tumor necrosis factor-alpha (TNF-α) appears to be linked with hyperandrogenism (HA), increased insulin resistance (IR), and obesity (Ob), which were common features noted with polycystic ovarian syndrome (PCOS). Our aim was to study the role of TNF-α in the pathogenesis of IR and Ob in PCOS, as well as a C850T (rs1799724) polymorphism in the promoter region of the TNF-α gene, in a group of 204 PCOS patients and 204 age-matched healthy controls. RESULTS: Significant differences were observed between PCOS patients and controls. All the PCOS had elevated body mass index, waist circumference, waist-to-hip ratio, fasting insulin, homeostatic model assessment (HOMA) score, and serum TNF-α when compared with controls (p<0.05). Genotype distribution for the C-850T polymorphism was observed with the frequency of the variant T allele being 0% in the PCOS group and 9% in the control group (p=0.0032). CONCLUSIONS: In conclusion, our present results suggest that the TNF-α system might contribute to the pathogenesis of HA, Ob, and IR in PCOS independent of a polymorphism of the TNF-α C850T (rs1799724) in our population.


Assuntos
Genótipo , Síndrome do Ovário Policístico , Polimorfismo Genético , Regiões Promotoras Genéticas , Fator de Necrose Tumoral alfa , Adolescente , Adulto , Feminino , Humanos , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/genética , Síndrome do Ovário Policístico/patologia , Fator de Necrose Tumoral alfa/sangue , Fator de Necrose Tumoral alfa/genética
6.
Enzyme Microb Technol ; 64-65: 67-73, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25152419

RESUMO

Bovine serum albumin (BSA) was adsorbed on allyl glycidyl ether (AGE)-ethylene glycol dimethacrylate (EGDM) copolymer with 25% crosslink density (AGE-25) at pH 8.0 (16% w/w). The amino, thiol and carboxylic acid functional groups available on protein coated surface were utilized for covalent immobilization of glucose oxidase and ß-galactosidase, both independently, and in a step-wise manner on the same matrix, with no more than 10% loss of enzyme activity during immobilization. Glutaraldehyde cross-linking after immobilization provided stable enzyme preparations. The pH-optima of the immobilized enzymes were similar to those for free enzyme but their thermal stability was vastly improved. The co-immobilized enzyme support was used as a biosensor for determination of lactose in milk with excellent reproducibility and reusability.


Assuntos
Técnicas Biossensoriais/métodos , Lactose/análise , Leite/química , Animais , Bovinos , Estabilidade Enzimática , Enzimas Imobilizadas , Compostos de Epóxi , Glucose Oxidase , Concentração de Íons de Hidrogênio , Indicadores e Reagentes , Cinética , Metacrilatos , Soroalbumina Bovina , Temperatura , beta-Galactosidase
7.
Int J Endocrinol Metab ; 12(1): e12470, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24696694

RESUMO

BACKGROUND: Polycystic ovarian syndrome (PCOS) is one of the most common endocrine conditions affecting women of reproductive age with a prevalence of approximately 5-10% worldwide. PCOS can be viewed as a heterogeneous androgen excess disorder with varying degrees of reproductive and metabolic abnormalities, whose diagnosis is based on anthropometric, biochemical and radiological abnormalities. To our knowledge, this is the first study investigating the anthropometric, biochemical and ultrasonographic characteristics of PCOS in Asian Indians of South India, using the Androgen Excess Society (AES-2006) diagnostic criteria. OBJECTIVES: To assess anthropometric, biochemical and ultrasonographic features of PCOS subgroups and controls among South Indian women using the AES-2006 criteria. MATERIALS AND METHODS: Two hundred and four women clinically diagnosed with PCOS, and 204 healthy women controls aged 17 to 35 years were evaluated. PCOS was diagnosed by clinical hyperandrogenism (HA), irregular menstruation (IM), and polycystic ovary (PCO). PCOS was further categorized into phenotypic subgroups including the IM+HA+PCO (n = 181, 89%), HA+PCO (n = 23, 11%), IM+HA (n = 0), and also into obese PCOS (n = 142, 70%) and lean PCOS (n = 62, 30%) using body mass index (BMI). Anthropometric measurements and biochemical characteristics were compared among the PCOS subgroups. RESULTS: The PCOS subgroups with regular menstrual cycles (HA+PCO), had more luteinizing hormone (LH), follicle stimulating hormone (FSH), fasting glucose, fasting insulin, and high insulin resistance (IR) expressed as the Homeostasis Model Assessment (HOMA) score, compared with the IM+HA+PCO subgroups and controls. Similarly, the obese PCOS had high BMI, waist to hip ratio (WHR), fasting glucose, LH, LH/FSH, fasting insulin, HOMA score (IR), and dyslipidemia, compared with lean PCOS and controls. Unilateral polycystic ovary was seen in 32 (15.7%) patients, and bilateral involvement in 172 (84.3%) patients. All the controls showed normal ovaries. CONCLUSIONS: Anthropometric, biochemical, and ultrasonographic findings showed significant differences among PCOS subgroups. The PCOS subgroups with regular menstrual cycles (HA+PCO), had high insulin resistance (IR) and gonadotropic hormonal abnormalities, compared with the IM+HA+PCO subgroups and controls.

8.
Colloids Surf B Biointerfaces ; 116: 201-5, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24480067

RESUMO

Trypsin adsorption from aqueous buffer by various copolymers of allyl glycidyl ether-ethylene glycol dimethacrylate (AGE-EGDM) copolymer with varying crosslink density increases with increasing crosslink density and the effect slowly wears off after reaching a plateau at 50% crosslink density. The copolymer with 25% crosslink density was reacted with different amines with alkyl/aryl side chains to obtain a series of copolymers with 1,2-amino alcohol functional groups and varying hydrophobicity. Trypsin binding capacity again increases with hydrophobicity of the reacting amine and a good correlation between logPoctanol of the amine and protein binding is observed. The bound trypsin is denatured to the extent of 90% in spite of the presence of hydrophilic hydroxyl and amino groups. The behavior was comparable to that in mixtures of aqueous buffer and water-miscible organic co-solvents where the solvent concentration required to deactivate 50% of the enzyme (C50) is dependent on logPoctanol of the co-solvent.


Assuntos
Polímeros/química , Tripsina/química , Adsorção , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Desnaturação Proteica , Solventes/química , Propriedades de Superfície , Tripsina/metabolismo
9.
Biotechnol Prog ; 30(2): 317-23, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24449609

RESUMO

Allyl glycidyl ether (AGE)-ethylene glycol dimethacrylate (EGDM) copolymer with 25% crosslink density (AGE-25) shows excellent bovine serum albumin (BSA) adsorption (up to 16% (w/w)) at pH 8.0 and the adsorbed BSA is strongly bound. This protein-coated polymer provides a novel matrix with naturally existing functional groups such as thiol, amino, and carboxylic acid that are available for covalent immobilization of functional enzymes. Employing appropriate strategies, trypsin as a model protein was covalently bound to BSA-coated matrix both independently, and in a stepwise manner on the same matrix, with less than 5% loss of enzyme activity during immobilization. Glutaraldehyde crosslinking after immobilization provide stable enzyme preparation with activity of 510 units/g recycled up to six times without loss of enzyme activity. AFM studies reveal that the polymer surface has protein peaks and valleys rather than a uniform monolayer distribution of the protein and the immobilized enzyme preparation can best be described as polymer supported cross-linked enzyme aggregates (CLEAs).


Assuntos
Enzimas Imobilizadas/química , Compostos de Epóxi/química , Metacrilatos/química , Soroalbumina Bovina/química , Tripsina/química , Animais , Bovinos , Estabilidade Enzimática , Enzimas Imobilizadas/metabolismo , Concentração de Íons de Hidrogênio , Ligação Proteica , Soroalbumina Bovina/metabolismo , Temperatura , Tripsina/metabolismo
10.
Org Biomol Chem ; 11(29): 4778-91, 2013 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-23778751

RESUMO

Novel quinazolinone based α-glucosidase inhibitors have been developed. For this purpose a virtual screening model has been generated and validated utilizing acarbose as a α-glucosidase inhibitor. Homology modeling, docking, and virtual screening were successfully employed to discover a set of structurally diverse compounds active against α-glucosidase. A search of a 3D database containing 22,500 small molecules using the structure based virtual model yielded ten possible candidates. All ten candidates were N-3-pyridyl-2-cyclopropyl quinazolinone-4-one derivatives, varying at the 6 position. This position was modified by Suzuki-Miyaura cross coupling with aryl, heteroaryl, and alkyl boronic acids. A catalyst screen was performed, and using the best optimal conditions, a series of twenty five compounds was synthesized. Notably, the C-C cross coupling reactions of the 6-bromo-2-cyclopropyl-3-(pyridyl-3-ylmethyl)quinazolin-4(3H)-one precursor have been accomplished at room temperature. A comparison of the relative reactivities of 6-bromo and 6-chloro-2,3-disubstituted quinazolinones with phenyl boronic acid was conducted. An investigation of pre-catalyst loading for the reaction of the 6-bromo-2-cyclopropyl-3-(pyridyl-3-ylmethyl)quinazolin-4(3H)-one substrate was also carried out. Finally, we submitted our compounds to biological assays against α-glucosidase inhibitors. Of these, three hits (compounds 4a, 4t and 4r) were potentially active as α-glucosidase inhibitors and showed activity with IC50 values <20 µM. Based on structural novelty and desirable drug-like properties, 4a was selected for structure-activity relationship study, and thirteen analogs were synthesized. Nine out of thirteen analogs acted as α-glucosidase inhibitors with IC50 values <10 µM. These lead compounds have desirable physicochemical properties and are excellent candidates for further optimization.


Assuntos
Inibidores Enzimáticos/farmacologia , Inibidores de Glicosídeo Hidrolases , Quinazolinonas/farmacologia , Temperatura , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Modelos Moleculares , Estrutura Molecular , Quinazolinonas/síntese química , Quinazolinonas/química , Relação Estrutura-Atividade , alfa-Glucosidases/metabolismo
11.
Chem Asian J ; 8(6): 1168-76, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23512685

RESUMO

An elegant reagent-controlled strategy has been developed for the generation of a diverse range of biologically active scaffolds from a chiral bicyclic lactam. Reduction of the chiral lactam with LAH or alkylation with LHMDS to trigger different cyclization reactions have been shown to generate privileged scaffolds, such as pyrrolidines, indolines, and cyclotryptamines. Their amenability to substitution allows us to create various compound libraries by using these scaffolds. In silico studies were used to estimate the drug-like properties of these compounds. Selected compounds were subjected to anticancer screening by using three different cell lines. In addition, all these compounds were subjected to antibacterial screening to gauge the spectrum of biological activity that was conferred by our DOS methodology. Gratifyingly, with no additional iterative cycles, our method directly generated anticancer compounds with potency at low nanomolar concentrations, as represented by spiroindoline 14.


Assuntos
Antibacterianos/síntese química , Antineoplásicos/síntese química , Compostos Heterocíclicos/síntese química , Lactamas Macrocíclicas/química , Compostos de Espiro/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ciclização , Compostos Heterocíclicos/química , Compostos Heterocíclicos/farmacologia , Humanos , Metilação , Testes de Sensibilidade Microbiana , Modelos Moleculares , Estrutura Molecular , Peso Molecular , Compostos de Espiro/química , Compostos de Espiro/farmacologia
12.
Bioorg Med Chem Lett ; 23(4): 1013-6, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23305918

RESUMO

We have developed the first total syntheses of marine natural products ma'edamines A (18) and B (20). Structurally, they contain a pyrazine-2-(1H)-one core and were screened for antiproliferative activity on several cancer cell lines. Out of the six cell lines tested, ma'edamines A and B showed significant cytotoxicity against human colon cancer line COLO 205 (IC(50) 7.9 and 10.3 µM, respectively), breast cancer cell line MCF-7 (IC(50): 6.9 and 10.5 µM, respectively) and human lung adenocarcinoma cell line A549 (IC(50): 12.2 and 15.4 µM, respectively). The apoptotic effect of ma'edamines was confirmed by comet assay. Hence ma'edamines are likely to be useful as leads for development of a new class of anti-cancer agents.


Assuntos
Produtos Biológicos/síntese química , Pirazinas/síntese química , Animais , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Linhagem Celular Tumoral , Ensaio Cometa , Humanos , Células MCF-7 , Neoplasias/tratamento farmacológico , Poríferos/química , Pirazinas/química , Pirazinas/farmacologia
13.
Appl Biochem Biotechnol ; 167(8): 2369-80, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22717769

RESUMO

Thermo- and alkali-stable xylanases produced from Thielaviopsis basicola (MTCC-1467) on low-cost carbon source like rice straw were evaluated for their potential application in biobleaching of wood kraft pulp. Enzyme treatment at retention time of 240 min with 20 IU/gm of dried pulp resulted in ~85.2 % of reduction in kappa number. When compared to control, 110.8, 93, and 72.2 % of enhancement in brightness (percent International Organization of Standardization), whiteness, and fluorescence, respectively, were observed for enzyme-treated pulp. Spectroscopic analysis showed significant release of chromophoric compounds from enzyme-treated pulp. Furthermore, scanning electron microscope studies of unbleached and enzyme bleached pulp revealed the effectiveness of enzymatic treatment. The enzyme-treated pulp subjected to later stages of chemical bleaching resulted in 16 % decrease in chlorine consumption along with considerable reduction in chemical oxygen demand percentage (14.5 %) level of effluent. Various pulp properties like fiber length, fiber width, burst strength, burst index, tear strength, tear index, tensile strength, and breaking length were also significantly improved after enzyme treatment when compared to control.


Assuntos
Ascomicetos/enzimologia , Biotecnologia/métodos , Endo-1,4-beta-Xilanases/química , Proteínas Fúngicas/química , Madeira/química , Ascomicetos/química , Biocatálise , Endo-1,4-beta-Xilanases/genética , Endo-1,4-beta-Xilanases/isolamento & purificação , Endo-1,4-beta-Xilanases/metabolismo , Estabilidade Enzimática , Proteínas Fúngicas/genética , Proteínas Fúngicas/isolamento & purificação , Proteínas Fúngicas/metabolismo , Temperatura Alta , Concentração de Íons de Hidrogênio
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