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1.
Artigo em Inglês | MEDLINE | ID: mdl-38655915

RESUMO

An easy way of synthesizing low-cost carbon nanomaterials without the need for high-temperature processing approach is critical for energy storage applications because the demand has increased for affordable, long-term, and environmentally friendly synthesized carbon-based materials. Herein, we synthesized multilayered graphitic carbon nano-onions (CNOs) using an oil-wick flame pyrolysis approach, employing biowaste (chicken fat) oil as a cost-effective precursor. The prepared CNOs can provide enhanced ion movement and less resistance for electron transport by interconnecting CNO particles with one another. Furthermore, heteroatom (S,N)-doped CNOs (h-CNOs) were synthesized to optimize the hydrophilic and conductive properties of carbon materials, which eventually exalted the capacitive charge transfer kinetics. The h-CNOs demonstrated superior, highest specific capacitance of 261 F/g, while the undoped CNOs showed a capacitance of 180.6 F/g at a current density of 1 A/g. In addition to capacitance, the h-CNOs also demonstrated a rate capability of 69% and a good cycling stability of 97.5% under high current densities. An asymmetric supercapacitor was fabricated using the h-CNOs as the negative and MnCo2S4 (MCS) as the positive electrode. The device showed high energy and power performance of 32.8 Wh/kg and 7350 W/kg, respectively, with a capacitance retention of 97% over 5000 cycles. Considering the facile strategic way to produce novel carbonaceous materials derived from biowaste oil (chicken fat oil), this could be considered a potential advantage for commercial energy storage devices and may open the door to producing inexpensive, industrially revolutionizing energy storage devices.

2.
Med J Armed Forces India ; 78(4): 448-453, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36267512

RESUMO

Background: Acute Pulmonary thromboembolism (PTE) is associated with acute hypoxemic respiratory failure (AHRF), which is a leading cause of death in these patients. High-Flow Nasal Cannula (HFNC) oxygen therapy is a cornerstone of the treatment of respiratory failure. The aim of the present study is to explore the efficacy of HFNC in the treatment of patients of acute PTE with acute hypoxemic respiratory failure in India. Methods: This is a retrospective study of patients admitted to a tertiary care center with acute PTE with AHRF during the period from January 2018 to January 2020. After reviewing medical files, patients of acute PTE with AHRF treated with HFNC were included in the study. We analyzed the improvement in oxygenation parameters and respiratory rate, as well as outcome in these patients. Results: During the above specified period, 12 patients suffering from PTE with AHRF were treated with HFNC. After 1 h of the initiation of HFNC along with anticoagulation, the respiratory parameters of patients significantly improved. HFNC was applied for a period of 6-10 days. None of the patients required intubation for AHRF, and all patients were discharged from the hospital on oral anticoagulants. Conclusion: HFNC oxygen therapy in patients with acute PTE with AHRF showed rapid improvement of oxygenation and respiratory rate. HFNC oxygen therapy is an efficacious treatment for patients with AHRF secondary to acute PTE without any significant hemodynamic effect. It acts as a superior modality of oxygen therapy avoiding noninvasive and invasive ventilatory support.

3.
ACS Omega ; 4(7): 12808-12816, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31460405

RESUMO

The major challenge in photodynamic therapy (PDT) is to discover versatile photosensitizers (PSs) that possess good solubility in biological media, enhanced singlet oxygen generation efficacy, and photodynamic activity. Working in this direction, we synthesized a picolylamine-functionalized porphyrin conjugate, compound 1, and its zinc complex compound 2. Compound 1 forms spherical structures in methanol, whereas compound 2 exhibited vesicular structures. Compared to the existing PSs like foscan and photofrin, compound 2 exhibited a high singlet oxygen generation efficiency and triplet quantum yield. The complex also showed good water solubility, and its PDT activity was demonstrated through in vitro studies using MDA-MB 231 breast cancer cells. The mechanism of biological activity evaluated using various techniques proved that the active compound 2 induced predominantly singlet oxygen-triggered apoptosis-mediated cancerous cell death. Our results demonstrate that zinc insertion in the picolyl porphyrin induces an enhanced triplet excited state, and the singlet oxygen yields quantitatively and imparts excellent in vitro photodynamic activity, thereby demonstrating their pertinence as a nanodrug in future photobiological applications.

4.
Natl Med J India ; 32(5): 288-289, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32985444

RESUMO

A 32-year-old woman presented to the neurology department with complaints of holocranial headache of 1-month duration, which was getting worse on sitting up and standing. Headache was not relieved with analgesics but on lying down. A provisional diagnosis of spontaneous intracranial hypotension was considered, which was confirmed by the findings on magnetic resonance imaging. She was given an epidural blood patch, which relieved her symptoms.


Assuntos
Placa de Sangue Epidural/métodos , Hipotensão Intracraniana/terapia , Adulto , Feminino , Humanos , Hipotensão Intracraniana/diagnóstico por imagem , Imageamento por Ressonância Magnética
5.
J Mater Chem B ; 7(14): 2372-2377, 2019 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-32254685

RESUMO

Herein, we synthesised four aza-BODIPY dyes (1-4) with the singlet oxygen generation quantum yield values of ca. 65-85%. Furthermore, we formulated a nanomedicine by encapsulating these dyes into an amphiphilic micelle, DSPE. The spherical nanomicelles formed were characterized using photophysical and morphological analyses, and their in vitro and in vivo photodynamic efficacies were investigated. One of the conjugates, DSPE-1, showed the lowest IC50 value of 2 µM against a human breast cancer cell line (MDA MB 231). The mechanism of photodynamic activity has been evaluated by employing different biophysical and morphological assays, which confirmed apoptotic cell death (ca. 80-90%) predominantly through the involvement of reactive oxygen species. Interestingly, we observed that 2 mg kg-1DSPE-1 induced enhanced apoptosis and efficient inhibition of the growth of breast tumor xenografts in NOD/SCID mice models. Herein, we demonstrated the application of aza-BODIPY nanomicelles in photodynamic therapy for the first time, and our results revealed that the DSPE-BODIPY nanomicelles enhanced the cellular uptake as well as the photodynamic activity, thereby demonstrating the use of these nanomicelles as efficient sensitizers in biological applications.


Assuntos
Apoptose/efeitos dos fármacos , Compostos de Boro/farmacologia , Neoplasias da Mama/tratamento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Oxigênio Singlete/metabolismo , Animais , Compostos de Boro/uso terapêutico , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Micelas , Nanopartículas/uso terapêutico , Fosfatidiletanolaminas/química , Fármacos Fotossensibilizantes/uso terapêutico , Polietilenoglicóis/química
6.
Arch Oral Biol ; 82: 19-26, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28578028

RESUMO

OBJECTIVE: Pathogens and host mediators can activate transcription factors in periodontal cells to bring about gene level alterations, thereby accentuating the periodontal disease process. Nuclear factor-kappa B (NF-κB) and signal transducers and activators of transcription 3 (STAT3) are two pivotal transcription factors implicated in chronic inflammatory diseases. But their importance in periodontal pathogenesis has not been investigated in detail. The aim of the present study was to evaluate the expression of activated transcription factors and their target genes in healthy and diseased periodontium. DESIGN: Primary culture of periodontal ligament fibroblasts (PDLF) were established from healthy and diseased periodontium using explant culture methods. NF-κB and STAT3 activation in these cells by Porphyromonas gingivalis LPS (lipopolysaccharide) was demonstrated using confocal microscopy and mRNA expression of target genes were evaluated by quantitative real time PCR. NF-κB and STAT3 expression in diseased and healthy gingival tissues were analyzed using immunohistochemistry. RESULTS: A basal upregulation of transcription factors and their target genes were noted in diseased PDLF compared to healthy ones. LPS challenge induced differential expression of NF-κB and STAT3 and their target genes in diseased PDLF compared to healthy ones. Immunohistochemical analysis revealed significant activation of transcription factors in diseased gingival tissues. CONCLUSION: The findings of the present study reveal the role of transcription factors NF-κB and STAT3 in periodontal pathogenesis and disease susceptibility of fibroblast subpopulations in periodontal disease could be mediated through activation of NF-κB and STAT3. Since genetic factors are nonmodifyable, transcription factors are promising targets for future host modulation therapy.


Assuntos
Fibroblastos/metabolismo , Gengiva/metabolismo , NF-kappa B/metabolismo , Doenças Periodontais/metabolismo , Ligamento Periodontal/citologia , Fator de Transcrição STAT3/metabolismo , Adulto , Feminino , Humanos , Imuno-Histoquímica , Lipopolissacarídeos/farmacologia , Masculino , Microscopia Confocal , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real
7.
Sci Rep ; 7: 42126, 2017 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-28169351

RESUMO

Photodynamic therapy (PDT) is a clinically established and highly evolving treatment modality for cancer. PDT utilizes a light responsive drug called photosensitizer that selectively destroys tumor cells upon light irradiation. Squaraines are a class of dyes possessing all favorable characteristics of a photosensitizer and have been considered to be a potent candidate for next generation PDT. In this study we chose an iodo derivative of squaraine called diiodo-squaraine (bis(3, 5-diiodo-2,4,6-trihydroxyphenyl)squaraine) which has been reported for its tumor specificity but least studied for its cellular and molecular functions. Our studies revealed that the iodo derivative of squaraine possess maximum photodynamic activity in human breast cancer cells MDA- MB- 231 and had very little cytotoxicity in normal breast cells MCF-10A. We analyzed its pro and anti-apoptotic events initiated by oxidative stress exploring a proteomic approach and delineated other critical molecular pathways and key proteins involved in regulating the complex network of cellular response upon PDT. Our study showed that, diiodo- squaraines predominantly accumulate in mitochondria and induce mitochondria-mediated apoptosis. Our study also reveals the novel mechanistic role of diiodo-squaraines to induce oxidative stress there by activating both protective and death inducing pathways post PDT.


Assuntos
Apoptose/efeitos dos fármacos , Ciclobutanos/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Fenóis/farmacologia , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Apoptose/genética , Apoptose/efeitos da radiação , Catalase/genética , Catalase/metabolismo , Linhagem Celular , Relação Dose-Resposta a Droga , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/efeitos da radiação , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Células HCT116 , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Células HeLa , Homeostase , Humanos , Luz , Células MCF-7 , Mitocôndrias/metabolismo , Mitocôndrias/efeitos da radiação , Especificidade de Órgãos , Oxirredução , Peroxirredoxina III/genética , Peroxirredoxina III/metabolismo , Fator de Transcrição CHOP/genética , Fator de Transcrição CHOP/metabolismo
8.
J Cell Biochem ; 118(4): 797-807, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27684411

RESUMO

Cyclin-dependent kinases (cdks) are central catalytic units of cell division cycle. Among the cdk family members, cdk1 has critical roles in multiple phases of the cell cycle. Aberrant expression or hyper-actions of cdk1 are tumorigenic and yet the complex oncogenic network that regulates its turnover is poorly understood. We found a hitherto unexplored functional connection between skp2 and cdk1 turn over. In vitro knockdown or overexpression of skp2 in cultured cells reduced or induced cdk1 expression indicating skp2 as a positive driver for cdk1. A partial inhibitory role for p27 was identified in this context. Interestingly, concurrent overexpression of skp2 and p27 favored cdk1 upregulation in vitro, which correlated well with similar observations in clinical tumor samples. We found that the transcription factor FOXM1 may play a central role in the skp2-cdk1 loop. Additional molecular involvement in the skp2-cdk1 loop was also explored. In conclusion, our results revealed hitherto unexplored p27 independent molecular mechanisms for skp2 driven tumor progression. Our results support the previous findings that skp2 may be a potential therapeutic target for the management of tumors. J. Cell. Biochem. 118: 797-807, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Quinases Ciclina-Dependentes/metabolismo , Proteína Forkhead Box M1/metabolismo , Proteínas Oncogênicas/metabolismo , Proteínas Quinases Associadas a Fase S/metabolismo , Fator de Ligação a CCAAT/genética , Fator de Ligação a CCAAT/metabolismo , Proteína Quinase CDC2 , Quinases relacionadas a CDC2 e CDC28/genética , Quinases relacionadas a CDC2 e CDC28/metabolismo , Carcinogênese/genética , Carcinogênese/metabolismo , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Ciclo Celular/genética , Ciclo Celular/fisiologia , Linhagem Celular Tumoral , Inibidor de Quinase Dependente de Ciclina p27/genética , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Quinases Ciclina-Dependentes/genética , Progressão da Doença , Proteína Forkhead Box M1/genética , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Leucoplasia Oral/genética , Leucoplasia Oral/metabolismo , Leucoplasia Oral/patologia , Modelos Biológicos , Neoplasias Bucais/genética , Neoplasias Bucais/metabolismo , Neoplasias Bucais/patologia , Proteínas Oncogênicas/antagonistas & inibidores , Proteínas Oncogênicas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , Proteínas Quinases Associadas a Fase S/antagonistas & inibidores , Proteínas Quinases Associadas a Fase S/genética , Transdução de Sinais , Regulação para Cima
9.
J Ethnopharmacol ; 196: 160-167, 2017 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-27993634

RESUMO

ETHANOPHARMACOLOGICAL RELEVANCE: Andrographolide is a herbal extract traditionally used in South Asian countries for treating inflammatory diseases. AIM OF THE STUDY: To evaluate the efficacy of andrographolide in management of periodontal disease which is a highly prevalent oral disease. MATERIALS AND METHODS: Periodontal ligament fibroblasts (PDLF) were cultured from healthy and diseased periodontium using explant culture methods. The safe dose of AG was determined using MTT assay. LPS (lipopolysaccharide) of the most important periodontopathogen, P gingivalis was used to activate NF-κB and STAT3 in PDLF. The efficacy of AG in inhibiting NF-κB and STAT3 was analyzed using immunofluorescence. Down regulation of expression of target genes of these transcription factors related to inflammation and bone resorption were analyzed using real time PCR. RESULTS: AG up to the concentration of 25µM was found to be safe as determined by MTT assay. Statistically significant activation of NF-κB and STAT3 in cultured PDLF was observed in diseased group compared to healthy controls before and after LPS challenge. 5µM AG pretreatment significantly inhibited activation of NF-κB and STAT3 and down regulated expression of inflammatory and bone resorptive genes in cultured PDLF. CONCLUSIONS: The findings of the present study propose the adjunctive use of a novel herbal drug andrographolide as a promising host modulation agent for periodontal therapy by inhibiting NF-κB and STAT3 activation and inhibition of inflammation and bone resorption related genes.


Assuntos
Anti-Inflamatórios/farmacologia , Diterpenos/farmacologia , Fibroblastos/efeitos dos fármacos , NF-kappa B/antagonistas & inibidores , Fator de Transcrição STAT3/antagonistas & inibidores , Adulto , Células Cultivadas , Ciclo-Oxigenase 2/genética , Feminino , Fibroblastos/metabolismo , Humanos , Interleucina-1beta/genética , Lipopolissacarídeos , Masculino , Metaloproteinase 9 da Matriz/genética , Pessoa de Meia-Idade , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Doenças Periodontais/tratamento farmacológico , Doenças Periodontais/metabolismo , Ligamento Periodontal/citologia , Ligante RANK/genética , RNA Mensageiro/metabolismo , Fator de Transcrição STAT3/metabolismo
10.
Dalton Trans ; 44(35): 15591-601, 2015 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-26244289

RESUMO

Novel biomimetic mononuclear complexes, [Fe()Cl2](+) () and [Cu()(H2O)](2+) () based on naphthalimide appended tripodal tetradentate ligand ( = 2,2',2''-(3,3',3''-(2,2',2''-nitrilotris(methylene)tris(1H-benzo[d]imidazole-2,1-diyl))tris(propane-3,1-diyl))tris(1H-benzo-[de]isoquinoline-1,3(2H)-dione)) have been synthesized and characterized by various analytical and spectral techniques. In addition, the structures of the ligand () and complex were established unambiguously through X-ray crystal structure analysis. Uniquely, the coordination with a metal ion modified the ligand scaffold to interact efficiently with ct-DNA (groove binding) as well as protein (hydrophobic and/or electrostatic interactions). We have determined the affinity of these complexes for DNA/protein and the values are found to be in the range, KDNA = 0.34-1.01 × 10(4) M(-1) and KBSA = 4.1-5.0 × 10(5) M(-1). Furthermore, the fluorescence quenching of BSA with complexes and occurs through a static mechanism and affects the conformation of BSA around the tryptophan residues. The in vitro biological studies of these systems employing HeLa cell lines indicated that both these complexes exhibited enhanced cytotoxicity (IC50 = 32 ± 0.19 and 10 ± 0.21 µM for complexes and , respectively), when compared to the ligand () (IC50 = 150 µM). Interestingly, both the complexes ( and ) were found to be non-toxic to normal H9C2 cell lines. The mechanism of in vitro biological activity of these complexes has been evaluated through a variety of techniques: acridine orange/ethidium bromide, DAPI staining studies, annexin V-FITC/PI and poly(ADP-ribose)-polymerase (PARP) cleavage, which confirmed the apoptotic mediated cell death. Our results demonstrate the importance of complexation of the naphthalimide ligand () as well as the potential of these biomimetic metal complexes as cytotoxic and anticancer agents.


Assuntos
Antineoplásicos/química , Complexos de Coordenação/química , Cobre/química , Compostos Ferrosos/química , Naftalimidas/química , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Bovinos , Complexos de Coordenação/farmacologia , Cobre/farmacologia , Cristalografia por Raios X , DNA/metabolismo , Compostos Ferrosos/farmacologia , Células HeLa , Humanos , Ligantes , Modelos Moleculares , Naftalimidas/farmacologia , Neoplasias/tratamento farmacológico
11.
ACS Chem Biol ; 8(1): 127-32, 2013 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-23092119

RESUMO

We synthesized a novel water-soluble porphyrin THPP and its metalated derivative Zn-THPP having excellent triplet excited state quantum yields and singlet oxygen generation efficiency. When compared to U.S. Food and Drug Administration approved and clinically used sensitizer Photofrin, THPP showed ca. 2-3-fold higher in vitro photodynamic activity in different cell lines under identical conditions. The mechanism of the biological activity of these porphyrin systems has been evaluated through a variety of techniques: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, comet assay, poly(ADP-ribose)polymerase (PARP) cleavage, CM-H(2)DCFDA assay, DNA fragmentation, flow cytometric analysis, fluorescence, and confocal microscopy, which confirm the apoptotic cell death through predominantly reactive oxygen species (ROS). Moreover, THPP showed rapid cellular uptake and are localized in the nucleus of the cells as compared to Hoechst dye and Photofrin, thereby demonstrating its use as an efficient sensitizer in photodynamic therapy and live cell NIR nucleus imaging applications.


Assuntos
Complexos de Coordenação/síntese química , Fármacos Fotossensibilizantes/síntese química , Porfirinas/síntese química , Zinco/química , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Complexos de Coordenação/farmacologia , Humanos , Microscopia Confocal , Estrutura Molecular , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/química , Porfirinas/farmacologia
12.
J Med Chem ; 55(11): 5110-20, 2012 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-22582931

RESUMO

A water-soluble derivative of N-confused porphyrin (NCP) was synthesized, and the photodynamic therapeutic (PDT) application was investigated by photophysical and in vitro studies. High singlet oxygen quantum yield in water at longer wavelength and promising IC(50) values in a panel of cancer cell lines ensure the potential candidacy of the sensitizer as a PDT drug. Reactive oxygen species (ROS) generation on PDT in MDA-MB 231 cells and the apoptotic pathway of cell death was illustrated using different techniques.


Assuntos
Benzenossulfonatos/síntese química , Fármacos Fotossensibilizantes/síntese química , Porfirinas/síntese química , Apoptose/efeitos dos fármacos , Benzenossulfonatos/química , Benzenossulfonatos/farmacologia , Linhagem Celular Tumoral , Cromatina/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Metanol/química , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/química , Porfirinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Oxigênio Singlete/química , Solubilidade , Água/química
13.
Genomics ; 98(3): 189-93, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21704150

RESUMO

MicroRNAs control gene expression at the posttranscriptional level by base-pairing to the 3'-UTR of their target mRNAs, thus leading to mRNA degradation of protein fabrication. We hypothesize, SNPs within miRNAs and their targets could be of significance to an individual's risk of developing cancer. We analyzed in silico SNP information on cervical cancer associated aberrant alleles and further investigated this in a case-control study by examining eleven SNPs from different genes. It was observed that a C to T polymorphism in putative miRNA target site of BCL2 was significantly conspicuous for the aberrant SNP allele in cancer tissues as compared to controls. This study provides evidence that SNPs in miRNA-binding sites may play an important role in increasing risk of cancer. The results also paves way for future studies to validate these results in other well-characterized populations as well as to explore the biological significance of these particular SNPs.


Assuntos
MicroRNAs/genética , Papillomaviridae/patogenicidade , Proteínas Proto-Oncogênicas c-bcl-2/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/virologia , Regiões 3' não Traduzidas/genética , Alelos , Sequência de Aminoácidos , Sítios de Ligação , Estudos de Casos e Controles , Biologia Computacional , Feminino , Estudo de Associação Genômica Ampla/métodos , Genótipo , Células HeLa , Humanos , MicroRNAs/metabolismo , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Polimorfismo de Nucleotídeo Único , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Alinhamento de Sequência , População Branca/genética
14.
Genomics ; 97(6): 333-40, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21377523

RESUMO

Accurate identification of mature miRNAs is an important requirement for exploring the post-transcriptional regulatory mechanism of organisms. In this work we present a novel computational tool 'Mpred' which first identifies pre-miRNAs and then predicts its mature miRNAs. We first use our method to learn with high accuracy characteristic features of human miRNA precursors from miRbase registry and then apply to sequences from fragile site regions related to cervical cancer in search of novel miRNA genes. The study identified 13 putative miRNA-like sequences and most of them were not related to each other and do not share homology with annotated sequences. Finally, four of the top scoring predictions were verified experimentally using quantitative RT-PCR validation. Expression profile studies revealed that four novel miRs were present in cervical tissues and these data compiled here provide a regulatory framework of miRNA genes that may have roles in tumorigenesis.


Assuntos
MicroRNAs/genética , Software , Neoplasias do Colo do Útero/genética , Inteligência Artificial , Sequência de Bases , Linhagem Celular Tumoral , Simulação por Computador , Feminino , Regulação Neoplásica da Expressão Gênica , Estudos de Associação Genética , Humanos , Cadeias de Markov , MicroRNAs/metabolismo , Modelos Genéticos , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Curva ROC , Neoplasias do Colo do Útero/metabolismo
15.
Indian J Pediatr ; 74(6): 577-9, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17595502

RESUMO

A 17-yr-old boy presented with hypogonadotropic hypogonadism due to sequelae of intrauterine infection with Toxoplasma Gondii. Neuroendocrine manifestations of congenital toxoplasmosis are especially uncommon. It is our attempt to stress the importance of endocrine monitoring for early recognition of treatable sequelae. This may help to improve the quality of life in these patients.


Assuntos
Hipogonadismo/diagnóstico , Toxoplasma/isolamento & purificação , Toxoplasmose Congênita/diagnóstico , Adolescente , Animais , Anticorpos Antiprotozoários/análise , Diagnóstico Diferencial , Seguimentos , Humanos , Índia , Masculino , Medição de Risco
17.
Carbohydr Res ; 339(1): 133-40, 2004 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-14659679

RESUMO

The oxidative degradation of D-fructose by vanadium(V) in the presence of H(2)SO(4) has an induction period followed by autoacceleration. The kinetics and mechanism of the induction period have been studied at constant ionic strength. The reaction was followed spectrophotometrically by measuring the changes in absorbance at 350 nm. Evidence of induced polymerization of acrylonitrile and of reduction of mercuric chloride indicates that a free-radical mechanism operates during the course of reaction. Vanadium(V) is only reduced to vanadium(IV). The reaction is first and fractional order in [V(V)] and [D-fructose], respectively; but dependence on [H+] is complex, that is, [equation: see text]. At constant [H2SO4], sodium hydrogensulfate accelerates the reaction. The effect of added sodium sulfate on the H2SO4 and HSO4-catalyzed reaction is also reported. The activation parameters Ea=118 kJ mol(-1), DeltaH#=116 kJ mol(-1), DeltaS#=-301 J K(-1) mol(-1), and DeltaG#=213 kJ mol(-1) are calculated and discussed. Reaction products are also examined, and it is concluded that oxidation of D-fructose by vanadium(V) involves consecutive one-electron abstraction steps.


Assuntos
Frutose/química , Ácidos Sulfúricos/química , Vanádio/química , Acrilonitrila/química , Radicais Livres/química , Cinética , Cloreto de Mercúrio/química , Oxirredução , Polímeros/química , Análise Espectral , Sulfatos/química , Temperatura
18.
Biol Reprod ; 65(2): 522-31, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11466221

RESUMO

In the highly organized and complex process of mammalian spermatogenesis, the development of an undifferentiated diploid germ cell into a fully differentiated and mature spermatozoon is orchestrated in a time frame unique for each species including man. If the various hormonal signals including environmental cues that play a critical part in initiating these events are not properly executed, various deficiencies including delay in sexual maturity or puberty are likely. In this study we have followed testicular development and spermatogenesis in the FSH receptor knockout (FORKO) mice from Day 7 onward by using histology and quantitative DNA flow cytometry. The drastic reduction in testicular weight and shrinkage of seminiferous tubules that occurred at this early age persisted into the adult stage in the FORKOs, suggesting inhibition of the initial developmental processes. The round spermatids that were clearly abundant on Day 21 in the wild-type and heterozygous males were few and present only in some tubules of the FORKOs. There were no elongated spermatids in FORKO males on Day 35. The sperm produced by Day 49 FORKOs were already aberrant, a feature that persisted into adulthood in these animals. As all these changes occurred in a background of normal circulating testosterone levels, we may conclude that the delay in testicular development is a consequence of the loss of FSH-receptor signaling. The delay in sexual maturity of FORKOs was accompanied by reduction in fertility as evidenced by mating studies. Based on these data we suggest that the FORKO mouse might be a useful experimental model to define the molecular mechanisms that underlie the delay in puberty.


Assuntos
Receptores do FSH/deficiência , Maturidade Sexual , Animais , Peso Corporal , Contagem de Células , DNA/análise , Epididimo/anatomia & histologia , Epididimo/crescimento & desenvolvimento , Citometria de Fluxo , Expressão Gênica , Heterozigoto , Masculino , Camundongos , Camundongos Knockout , Tamanho do Órgão , Receptores do FSH/genética , Receptores do FSH/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Túbulos Seminíferos/anatomia & histologia , Células de Sertoli , Contagem de Espermatozoides , Espermátides/citologia , Espermatogênese , Fator de Células-Tronco/genética , Testículo/citologia , Testículo/crescimento & desenvolvimento , Testosterona/sangue
19.
Endocrinology ; 142(1): 381-9, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11145601

RESUMO

The acquisition of FSH receptor(s) during follicular growth and their coupling to signaling pathways are key events in follicular development and dominance. However, little is known about the precise nature of the FSH receptor(s) involved in the growth-promoting phases of hormone action. To investigate the hormonal regulation of a newly discovered, alternatively spliced, growth factor type 1 receptor (designated FSH-R3) for the hormone, we examined expression in the adult mouse and the effect of PMSG treatment in the immature mouse ovary. Using RT-PCR and primers based on the established sheep ovarian transcript, a part of the FSH-R3 message was amplified only in wild-type (+/+), but not in the FSH-R knockout (-/-), mouse ovary. Semiquantitative RT-PCR using 3'-end primers specific for FSH-R1 (G(s)-coupled) and FSH-R3 indicated expression levels of the latter to be higher when follicular growth was induced by PMSG. Using FSH-R3-specific peptide IgG, FSH-R3 protein was detected by Western blotting in extracts of adult mouse ovary and was localized in granulosa cell membrane of mature follicles. In the immature mouse, levels of FSH-R3 protein that increased after PMSG administration in a time-dependent manner were also localized only on granulosa cell membranes of large follicles. The results reveal for the first time the expression of a different growth-promoting receptor for FSH in the developing and cycling mouse ovary. These observations introduce a new paradigm in the control of ovarian function.


Assuntos
Processamento Alternativo , Ovário/fisiologia , Receptores do FSH/fisiologia , Receptores da Somatotropina/genética , Transcrição Gênica/fisiologia , Sequência de Aminoácidos , Animais , Feminino , Amplificação de Genes , Gonadotropinas Equinas/farmacologia , Camundongos , Camundongos Knockout , Modelos Moleculares , Dados de Sequência Molecular , Folículo Ovariano/fisiologia , Ovário/efeitos dos fármacos , Estrutura Secundária de Proteína , Receptores do FSH/deficiência , Receptores do FSH/genética , Receptores da Somatotropina/química , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ovinos , Transcrição Gênica/efeitos dos fármacos
20.
Endocrinology ; 141(11): 4295-308, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11089565

RESUMO

Targeted disruption of the receptor for glycoprotein hormone, FSH (FSH-R) causes a gene dose-related endocrine and gametogenic abnormality in female mice. The resulting FSH-R knockout (FORKO) mutants have disordered estrous cycles, ovulatory defects, and atrophic uterus. The heterozygous animals that initially show reduced fertility undergo early reproductive senescence and stop breeding altogether. Lack of FSH-R signaling in females causes severe ovarian underdevelopment producing chronic estrogen deficiency. This was accompanied by increases in serum testosterone levels. Ovarian aromatase gene transcription and translation are unaltered in the mutants. Early loss of estrogen in the null mutants leads to obesity and skeletal abnormalities that intensify with age producing (kyphosis), a hunchback appearance. Both these changes also become apparent in older heterozygous mice coincident with early reproductive senescence. The expression of nuclear estrogen receptor(s) alpha and beta genes and the corresponding proteins in the ovary and uterus of FORKO mice appear to be intact. The loss of ovarian estrogen creates an imbalance in A and B forms of the progesterone receptor in the uterus of both heterozygotes and null mutants. Some of the changes we have documented here in FORKO mice are reminiscent of the ovarian dysfunction and other major symptoms that are usually associated with estrogen deficiency. In null mutants, estradiol-17beta administration promptly induced uterine growth and reversed the accumulation of adipose tissue indicating that estrogen receptors are functional. Thus, the phenotypes evident in these genetically altered FSH-R mutants may provide an experimental system to explore the effects of estrogenic compounds on different targets including the ovary in a nonsurgical setting.


Assuntos
Doenças Ósseas/genética , Estrogênios/deficiência , Obesidade/genética , Receptores do FSH/deficiência , Animais , Atrofia , Cruzamentos Genéticos , Estradiol/análise , Estradiol/sangue , Estradiol/farmacologia , Estrogênios/fisiologia , Feminino , Heterozigoto , Cifose/genética , Masculino , Camundongos , Camundongos Knockout , Tamanho do Órgão/efeitos dos fármacos , Progesterona/análise , Progesterona/sangue , Receptores Citoplasmáticos e Nucleares/fisiologia , Receptores do FSH/genética , Reprodução , Testosterona/sangue , Útero/patologia , Vagina/patologia
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