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1.
Int J Cancer ; 144(7): 1735-1745, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30289977

RESUMO

Glioblastoma multiforme (GBM) has a poor prognosis with an overall survival of 14-15 months after surgery, radiation and chemotherapy using temozolomide (TMZ). A major problem is that the tumors acquire resistance to therapy. In an effort to improve the therapeutic efficacy of TMZ, we performed a genome-wide RNA interference (RNAi) synthetic lethality screen to establish a functional gene signature for TMZ sensitivity in human GBM cells. We then queried the Connectivity Map database to search for drugs that would induce corresponding changes in gene expression. By this approach we identified several potential pharmacological sensitizers to TMZ, where the most potent drug was the established antipsychotic agent Thioridazine, which significantly improved TMZ sensitivity while not demonstrating any significant toxicity alone. Mechanistically, we show that the specific chemosensitizing effect of Thioridazine is mediated by impairing autophagy, thereby preventing adaptive metabolic alterations associated with TMZ resistance. Moreover, we demonstrate that Thioridazine inhibits late-stage autophagy by impairing fusion between autophagosomes and lysosomes. Finally, Thioridazine in combination with TMZ significantly inhibits brain tumor growth in vivo, demonstrating the potential clinical benefits of compounds targeting the autophagy-lysosome pathway. Our study emphasizes the feasibility of exploiting drug repurposing for the design of novel therapeutic strategies for GBM.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Autofagia/efeitos dos fármacos , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Temozolomida/administração & dosagem , Tioridazina/administração & dosagem , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Autofagossomos/efeitos dos fármacos , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Sinergismo Farmacológico , Glioblastoma/genética , Humanos , Lisossomos/efeitos dos fármacos , Camundongos , Mutações Sintéticas Letais , Temozolomida/uso terapêutico , Tioridazina/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Physiol Plant ; 149(3): 432-47, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23521023

RESUMO

A field experiment was carried out in order to evaluate genetic diversity of 41 rice genotypes using physiological traits and molecular markers. All the genotypes unveiled variations for crop growth rate (CGR), relative growth rate (RGR), net assimilation rate (NAR), yield per hill (Yhill(-1)), total dry matter (TDM), harvest index (HI), photosynthetic rate (PR), leaf area index (LAI), chlorophyll-a and chlorophyll-b at maximum tillering stage. The CGR values varied from 0.23 to 0.76 gm cm(-2) day(-1). The Yhill(-1) ranged from 15.91 to 92.26 g, while TDM value was in the range of 7.49 to 20.45 g hill(-1). PR was found to vary from 9.40 to 22.34 µmol m(-2) s(-1). PR expressed positive relation with Yhill(-1). Significant positive relation was found between CGR and TDM (r = 0.61**), NAR and CGR (r = 0.62**) and between TDM and NAR (r = 0.31**). High heritability was found in RGR and Yhill(-1). Cluster analysis based on the traits grouped 41 rice genotypes into seven clusters. A total of 310 polymorphic loci were detected across the 20 inter-simple sequence repeats (ISSR) markers. The UPGMA dendrogram grouped 41 rice genotypes into 11 clusters including several sub-clusters. The Mantel test revealed positive correlation between quantitative traits and molecular markers (r = 0.41). On the basis of quantitative traits and molecular marker analyses parental genotypes, IRBB54 with MR84, IRBB60 with MR84, Purbachi with MR263, IRBB65 with BR29, IRBB65 with Pulut Siding and MRQ74 with Purbachi could be hybridized for future breeding program.


Assuntos
Biomassa , Variação Genética , Genótipo , Oryza/genética , Desenvolvimento Vegetal , Análise por Conglomerados , Repetições de Microssatélites , Oryza/crescimento & desenvolvimento , Oryza/imunologia , Doenças das Plantas , Análise de Componente Principal , Característica Quantitativa Herdável , Técnica de Amplificação ao Acaso de DNA Polimórfico
3.
Environ Health Insights ; 17: 11786302231200997, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37766736

RESUMO

Background: The burden of acute respiratory infections (ARIs) among children under-five is a serious concern in lower and middle-income countries (LMICs), including India, where it is positively associated with indoor smoking exposures. This study re-examines the impact of maternal smoking on ARIs among children under 5 in India, considering other indoor air pollutant factors and covariates. The aim is to establish existing findings and capture any differentials in results using comprehensive analytical approaches. Methods: Data from the National Family Health Survey (NFHS-5), 2019 - 21, was used. Descriptive statistics, bivariate analysis, multivariable logistic regression models, and interaction analysis were applied to accomplish the study objective. Results: The adjusted likelihood of ARI was 1.24 (95% CI: 1.04-1.48) times higher in under-five children with smoking mothers than those with non-smoking mothers. The result was also observed to be almost similar across all seasons. Moreover, the combined effect of maternal smoking with other household members smoking and using unclean cooking fuel without a separate ventilated kitchen escalated the risk (AOR: 2.01; 95% CI: 1.98-2.67). Breastfeeding was found to be a preventive measure for reducing the risk of indoor smoking exposure. The children who were never breastfed and were born large or small were more susceptible to maternal smoking. Conclusion: The study highlights the association between maternal smoking and ARIs in Indian under-five children. Interventions include reducing maternal smoking, promoting breastfeeding, and improving respiratory health in fuel-exposed households.

4.
Plants (Basel) ; 12(9)2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-37176922

RESUMO

The application of Trichoderma is a form of biological control that has been effective in combating Xanthomonas oryzae pv. oryzae, the causative agent of the devastating disease known as bacterial blight of rice. In this present study, four strains of Trichoderma, viz., T. paraviridescens (BDISOF67), T. erinaceum (BDISOF91), T. asperellum (BDISOF08), and T. asperellum (BDISOF09), were collected from the rice rhizosphere and used to test their potentiality in reducing bacterial blight. The expression patterns of several core defense-related enzymes and genes related to SA and JA pathways were studied to explore the mechanism of induced resistance by those Trichoderma strains. The results primarily indicated that all Trichoderma were significantly efficient in reducing the lesion length of the leaf over rice check variety (IR24) through enhancing the expression of core defense-related enzymes, such as PAL, PPO, CAT, and POD activities by 4.27, 1.77, 3.53, and 1.57-fold, respectively, over control. Moreover, the results of qRT-PCR exhibited an upregulation of genes OsPR1, OsPR10, OsWRKY45, OsWRKY62, OsWRKY71, OsHI-LOX, and OsACS2 after 24 h of inoculation with all tested Trichoderma strains. However, in the case of RT-PCR, no major changes in OsPR1 and OsPR10 expression were observed in plants treated with different Trichoderma strains during different courses of time. Collectively, Trichoderma induced resistance in rice against X. oryzae pv. oryzae by triggering these core defense-related enzymes and genes associated with SA and JA pathways.

5.
Neuro Oncol ; 24(4): 541-553, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-34543427

RESUMO

BACKGROUND: Microtubes (MTs), cytoplasmic extensions of glioma cells, are important cell communication structures promoting invasion and treatment resistance through network formation. MTs are abundant in chemoresistant gliomas, in particular, glioblastomas (GBMs), while they are uncommon in chemosensitive IDH-mutant and 1p/19q co-deleted oligodendrogliomas. The aim of this study was to identify potential signaling pathways involved in MT formation. METHODS: Bioinformatics analysis of TCGA was performed to analyze differences between GBM and oligodendroglioma. Patient-derived GBM stem cell lines were used to investigate MT formation under transforming growth factor-beta (TGF-ß) stimulation and inhibition in vitro and in vivo in an orthotopic xenograft model. RNA sequencing and proteomics were performed to detect commonalities and differences between GBM cell lines stimulated with TGF-ß. RESULTS: Analysis of TCGA data showed that the TGF-ß pathway is highly activated in GBMs compared to oligodendroglial tumors. We demonstrated that TGF-ß1 stimulation of GBM cell lines promotes enhanced MT formation and communication via calcium signaling. Inhibition of the TGF-ß pathway significantly reduced MT formation and its associated invasion in vitro and in vivo. Downstream of TGF-ß, we identified thrombospondin 1 (TSP1) as a potential mediator of MT formation in GBM through SMAD activation. TSP1 was upregulated upon TGF-ß stimulation and enhanced MT formation, which was inhibited by TSP1 shRNAs in vitro and in vivo. CONCLUSION: TGF-ß and its downstream mediator TSP1 are important mediators of the MT network in GBM and blocking this pathway could potentially help to break the complex MT-driven invasion/resistance network.


Assuntos
Glioblastoma , Glioma , Oligodendroglioma , Glioblastoma/patologia , Humanos , Trombospondina 1/genética , Trombospondina 1/metabolismo , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo
6.
Bioinformation ; 11(11): 493-500, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26912949

RESUMO

Streptomyces xinghaiensis is a Gram-positive, aerobic and non-motile bacterium. The bacterial genome is known. Therefore, it is of interest to study the uncharacterized proteins in the genome. An uncharacterized protein (gi|518540893|86 residues) in the genome was selected for a comprehensive computational sequence-structure-function analysis using available data and tools. Subcellular localization of the targeted protein with conserved residues and assigned secondary structures is documented. Sequence homology search against the protein data bank (PDB) and non-redundant GenBank proteins using BLASTp showed different homologous proteins with known antitoxin function. A homology model of the target protein was developed using a known template (PDB ID: 3CTO:A) with 62% sequence similarity in HHpred after assessment using programs PROCHECK and QMEAN6. The predicted active site using CASTp is analyzed for assigned anti-toxin function. This information finds specific utility in annotating the said uncharacterized protein in the bacterial genome.

7.
PLoS One ; 9(10): e97241, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25285745

RESUMO

A study was conducted to determine the total microbial population, the occurrence of growth promoting bacteria and their beneficial traits in acid sulfate soils. The mechanisms by which the bacteria enhance rice seedlings grown under high Al and low pH stress were investigated. Soils and rice root samples were randomly collected from four sites in the study area (Kelantan, Malaysia). The topsoil pH and exchangeable Al ranged from 3.3 to 4.7 and 1.24 to 4.25 cmol(c) kg(-1), respectively, which are considered unsuitable for rice production. Total bacterial and actinomycetes population in the acidic soils were found to be higher than fungal populations. A total of 21 phosphate-solubilizing bacteria (PSB) including 19 N2-fixing strains were isolated from the acid sulfate soil. Using 16S rRNA gene sequence analysis, three potential PSB strains based on their beneficial characteristics were identified (Burkholderia thailandensis, Sphingomonas pituitosa and Burkholderia seminalis). The isolated strains were capable of producing indoleacetic acid (IAA) and organic acids that were able to reduce Al availability via a chelation process. These PSB isolates solubilized P (43.65%) existing in the growth media within 72 hours of incubation. Seedling of rice variety, MR 219, grown at pH 4, and with different concentrations of Al (0, 50 and 100 µM) was inoculated with these PSB strains. Results showed that the bacteria increased the pH with a concomitant reduction in Al concentration, which translated into better rice growth. The improved root volume and seedling dry weight of the inoculated plants indicated the potential of these isolates to be used in a bio-fertilizer formulation for rice cultivation on acid sulfate soils.


Assuntos
Bactérias/metabolismo , Oryza/crescimento & desenvolvimento , Oryza/microbiologia , Fosfatos/química , Microbiologia do Solo , Solo/química , Sulfatos/química , Alumínio/toxicidade , Bactérias/isolamento & purificação , Relação Dose-Resposta a Droga , Concentração de Íons de Hidrogênio , Fixação de Nitrogênio , Oryza/efeitos dos fármacos , Rizosfera , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Solubilidade
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