Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Stem Cell Rev Rep ; 17(5): 1827-1839, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33954878

RESUMO

Cancer is a devastating disease whose incidence has increased in recent times and early detection can lead to effective treatment. Existing detection tools suffer from low sensitivity and specificity, and are high cost, invasive and painful procedures. Cancers affecting different tissues, ubiquitously express embryonic markers including Oct-4A, whose expression levels have also been correlated to staging different types of cancer. Cancer stem cells (CSCs) that initiate cancer are possibly the 'transformed' and pluripotent very small embryonic-like stem cells (VSELs) that also express OCT-4A. Excessive self-renewal of otherwise quiescent, pluripotent VSELs in normal tissues possibly initiates cancer. In an initial study on 120 known cancer patients, it was observed that Oct-4A expression in peripheral blood correlated well with the stage of cancer. Based on these results, we developed a proprietary HrC scale wherein fold change of OCT-4A was linked to patient status - it is a numerical scoring system ranging from non-cancer (0-2), inflammation (>2-6), high-risk (>6-10), stage I (>10-20), stage II (>20-30), stage III (>30-40), and stage IV (>40) cancers. Later the scale was validated on 1000 subjects including 500 non-cancer and 500 cancer patients. Ten case studies are described and show (i) HrC scale can detect cancer, predict and monitor treatment outcome (ii) is superior to evaluating circulating tumor cells and (iii) can also serve as an early biomarker. HrC method is a novel breakthrough, non-invasive, blood-based diagnostic tool that can detect as well as classify solid tumors, hematological malignancies and sarcomas, based on their stage.


Assuntos
Neoplasias , Humanos , Neoplasias/diagnóstico , Neoplasias/genética , Fator 3 de Transcrição de Octâmero
2.
PLoS Biol ; 17(8): e3000422, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31398188

RESUMO

Histone H3 and its variants regulate gene expression but the latter are absent in most ascomycetous fungi. Here, we report the identification of a variant histone H3, which we have designated H3VCTG because of its exclusive presence in the CTG clade of ascomycetes, including Candida albicans, a human pathogen. C. albicans grows both as single yeast cells and hyphal filaments in the planktonic mode of growth. It also forms a three-dimensional biofilm structure in the host as well as on human catheter materials under suitable conditions. H3VCTG null (hht1/hht1) cells of C. albicans are viable but produce more robust biofilms than wild-type cells in both in vitro and in vivo conditions. Indeed, a comparative transcriptome analysis of planktonic and biofilm cells reveals that the biofilm circuitry is significantly altered in H3VCTG null cells. H3VCTG binds more efficiently to the promoters of many biofilm-related genes in the planktonic cells than during biofilm growth, whereas the binding of the core canonical histone H3 on the corresponding promoters largely remains unchanged. Furthermore, biofilm defects associated with master regulators, namely, biofilm and cell wall regulator 1 (Bcr1), transposon enhancement control 1 (Tec1), and non-dityrosine 80 (Ndt80), are significantly rescued in cells lacking H3VCTG. The occupancy of the transcription factor Bcr1 at its cognate promoter binding sites was found to be enhanced in the absence of H3VCTG in the planktonic form of growth resulting in enhanced transcription of biofilm-specific genes. Further, we demonstrate that co-occurrence of valine and serine at the 31st and 32nd positions in H3VCTG, respectively, is essential for its function. Taken together, we show that even in a unicellular organism, differential gene expression patterns are modulated by the relative occupancy of the specific histone H3 type at the chromatin level.


Assuntos
Biofilmes/crescimento & desenvolvimento , Candida albicans/genética , Histonas/metabolismo , Candidíase/microbiologia , Cromatina/genética , Cromatina/metabolismo , Proteínas Fúngicas/metabolismo , Expressão Gênica/genética , Regulação Fúngica da Expressão Gênica/genética , Redes Reguladoras de Genes/genética , Histonas/genética , Humanos , Fatores de Transcrição/metabolismo
3.
FEMS Microbiol Lett ; 365(22)2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30295732

RESUMO

Poly-γ-glutamic acid (PGA) is biosynthesized by various Bacillus species through PGA synthetase, encoded by the PGA operon comprised of the ywsC and ywtABC genes. Due to the minimal available knowledge, understanding the expression pattern of PGA operon genes is pivotal. In this study, the effect of glucose and glutamic acid on the global gene expression profile of Bacillus subtilis Natto3 was investigated using high throughput microarray, with an emphasis on the PGA operon and genes influencing PGA production. Two treatment groups (set1-in the presence of glutamic acid and set2-in the presence of glutamic acid + glucose) were analyzed against the control (in the presence of glucose). In the microarray, both the groups showed a trend of up-regulation for ywsC and ywtA genes (log2 fold change of 0.55, P = 0.0194, 0.92, P = 0.0069 in set1 and 0.78, P = 0.0023, 0.59, P = 0.0172 in set2, respectively) and down-regulation of ywtB and ywtC genes (log2 fold change of -1.83, P = 0.0001, -1.42, P = 0.0017 in set1 and -1.52, P = 0.0012, -0.55, P = 0.1112 in set2, respectively), supporting the indispensability of the ywsC and ywtA genes in PGA production. Interestingly, the ywtB and ywtC genes, belonging to the same operon, were down-regulated in both the conditions (set1 and set2). To the best of our knowledge, this expression pattern of PGA operon genes is a unique observation.


Assuntos
Bacillus subtilis/genética , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Ácido Glutâmico/farmacologia , Óperon/efeitos dos fármacos , Peptídeo Sintases/genética , Ácido Poliglutâmico/análogos & derivados , Bacillus subtilis/efeitos dos fármacos , Bacillus subtilis/enzimologia , Proteínas de Bactérias/genética , Regulação para Baixo/efeitos dos fármacos , Glucose/farmacologia , Análise de Sequência com Séries de Oligonucleotídeos , Ácido Poliglutâmico/biossíntese , Ácido Poliglutâmico/genética , Regulação para Cima/efeitos dos fármacos
4.
Microb Pathog ; 115: 343-352, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29197526

RESUMO

The immune signalling genes during the challenge of bovine macrophages with bacterial products derived from tuberculosis causing bacteria in cattle were investigated in the present study. An in-vitro cell culture model of bovine monocyte-derived macrophages were challenged to Mycobacterium bovis. Macrophages from healthy and already infected animals can both be fully activated during M. bovis infection. Analysis of mRNA abundance in peripheral blood mononuclear cells from M. bovis infected and non-infected cattle were performed as a controls. Cells of treatment were challenged after six days for six hours incubation at 37 °C, with 5% CO2, to total RNA was extracted then cDNA labelling, hybridization and scanning for microarray methods have been developed for microarray based immune related gene expression analysis. The differential expressions twenty genes (IL1, CCL3, CXCR4, TNF, TLR2, IL12, CSF3, CCR5, CCR3, MAPT, NFKB1, CCL4, IL6, IL2, IL23A, CCL20, IL8, CXCL8, TRIP10, CXCL2 and IL1B) implicated in M. bovis response were examined Agilent Bovine_GXP_8 × 60 K microarray platform. Cells of treatment were challenged after six days for six hours incubation then pathways analysis of Toll like receptor and Chemokine signalling pathway study of responsible genes in bovine tuberculosis. The PBMC from M. bovis infected cattle exhibit different transcriptional profiles compared with PBMC from healthy control animals in response to M. bovis antigen stimulation, providing evidence of a novel genes expression program due to M. bovis exposure. It will guide future studies, regarding the complex macrophage specific signalling pathways stimulated upon phagocytosis of M. bovis and role of signalling pathways in creating the host immune response to cattle tuberculosis.


Assuntos
Regulação da Expressão Gênica/imunologia , Ativação de Macrófagos/genética , Ativação de Macrófagos/imunologia , Macrófagos/imunologia , Mycobacterium bovis/imunologia , Tuberculose Bovina/imunologia , Animais , Bovinos , Células Cultivadas , Macrófagos/microbiologia , Fagocitose/genética , RNA Mensageiro/genética , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Tuberculose Bovina/microbiologia
5.
J Neurochem ; 143(3): 334-358, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28801915

RESUMO

Idiopathic Parkinson's disease and manganese-induced atypical parkinsonism are characterized by movement disorder and nigrostriatal pathology. Although clinical features, brain region involved and responsiveness to levodopa distinguish both, differences at the neuronal level are largely unknown. We studied the morphological, neurophysiological and molecular differences in dopaminergic neurons exposed to the Parkinson's disease toxin 1-methyl-4-phenylpyridinium ion (MPP+ ) and manganese (Mn), followed by validation in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine and Mn mouse models. Morphological analysis highlighted loss of neuronal processes in the MPP+ and not the Mn model. Cellular network dynamics of dopaminergic neurons characterized by spike frequency and inter-spike intervals indicated major neuronal population (~ 93%) with slow discharge rates (0-5 Hz). While MPP+ exposure suppressed the firing of these neurons, Mn neither suppressed nor elevated the neuronal activity. High-throughput transcriptomic analysis revealed up-regulation of 694 and 603 genes and down-regulation of 428 and 255 genes in the MPP+ and Mn models respectively. Many differentially expressed genes were unique to either models and contributed to neuroinflammation, metabolic/mitochondrial function, apoptosis and nuclear function, synaptic plasticity, neurotransmission and cytoskeleton. Analysis of the Janus kinase-signal transducer and activator of transcription pathway with implications for neuritogenesis and neuronal proliferation revealed contrasting profile in both models. Genome-wide DNA methylomics revealed differences between both models and substantiated the epigenetic basis of the difference in the Janus kinase-signal transducer and activator of transcription pathway. We conclude that idiopathic Parkinson's disease and atypical parkinsonism have divergent neurotoxicological manifestation at the dopaminergic neuronal level with implications for pathobiology and evolution of novel therapeutics. Cover Image for this issue: doi. 10.1111/jnc.13821.


Assuntos
1-Metil-4-fenilpiridínio/toxicidade , Neurônios Dopaminérgicos/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Manganês/toxicidade , Neurotoxinas/toxicidade , Potenciais de Ação/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Linhagem Celular Transformada , Sobrevivência Celular/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Neurônios Dopaminérgicos/citologia , Neurônios Dopaminérgicos/ultraestrutura , L-Lactato Desidrogenase/metabolismo , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Redes Neurais de Computação , Ratos , Transdução de Sinais/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Transcriptoma/fisiologia , Tirosina 3-Mono-Oxigenase/metabolismo
6.
Genom Data ; 2: 199-201, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26484095

RESUMO

Natural antisense transcripts (NATs) have been detected in many organisms and shown to regulate gene expression. Similarly, NATs have also been observed in malaria parasites with most studies focused on Plasmodium falciparum. There were no reports on the presence of NATs in Plasmodium vivax, which has also been shown to cause severe malaria like P. falciparum, until a recent study published by us. To identify in vivo prevalence of antisense transcripts in P. vivax clinical isolates, we performed whole genome expression profiling using a custom designed strand-specific microarray that contains probes for both sense and antisense strands. Here we describe the experimental methods and analysis of the microarray data available in Gene Expression Omnibus (GEO) under GSE45165. Our data provides a resource for exploring the presence of antisense transcripts in P. vivax isolated from patients showing varying clinical symptoms. Related information about the description and interpretation of the data can be found in a recent publication by Boopathi and colleagues in Infection, Genetics and Evolution 2013.

7.
Infect Genet Evol ; 20: 428-43, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24121022

RESUMO

Plasmodium vivax is the most geographically widespread human malaria parasite causing approximately 130-435 million infections annually. It is an economic burden in many parts of the world and poses a public health challenge along with the other Plasmodium sp. The biology of this parasite is less studied and poorly understood, in spite of these facts. Emerging evidence of severe complications due to infections by this parasite provides an impetus to focus research on the same. Investigating the parasite directly from infected patients is the best way to study its biology and pathogenic mechanisms. Gene expression studies of this parasite directly obtained from the patients has provided evidence of gene regulation resulting in varying amount of transcript levels in the different blood stages. The mechanisms regulating gene expression in malaria parasites are not well understood. Discovery of Natural Antisense Transcripts (NATs) in Plasmodium falciparum has suggested that these might play an important role in regulating gene expression. We report here the genome-wide occurrence of NATs in P. vivax parasites from patients with differing clinical symptoms. A total of 1348 NATs against annotated gene loci have been detected using a custom designed microarray with strand specific probes. Majority of NATs identified from this study shows positive correlation with the expression pattern of the sense (S) transcript. Our data also shows condition specific expression patterns of varying S and antisense (AS) transcript levels. Genes with AS transcripts enrich to various biological processes. To our knowledge this is the first report on the presence of NATs from P. vivax obtained from infected patients with different disease complications. The data suggests differential regulation of gene expression in diverse clinical conditions, as shown by differing sense/antisense ratios and would lead to future detailed investigations of gene regulation.


Assuntos
Elementos Antissenso (Genética)/genética , Regulação da Expressão Gênica/genética , Malária Vivax/genética , Plasmodium vivax/genética , RNA Antissenso/genética , Adolescente , Adulto , Mapeamento Cromossômico , Feminino , Humanos , Malária Vivax/parasitologia , Masculino , Plasmodium vivax/isolamento & purificação , RNA de Protozoário/sangue , RNA de Protozoário/genética , Transcrição Gênica , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...