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1.
Ann Indian Acad Neurol ; 25(6): 1116-1121, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36911481

RESUMO

Introduction/Aims: Studies conducted during the coronavirus disease 2019 (COVID-19) pandemic have reported varied data regarding the incidence of Guillain-Barre syndrome (GBS). The present study investigated demographic and clinical features, management, and outcomes of patients with GBS during a specified period of the COVID-19 pandemic, and compared these features to those of GBS in the previous year. Methods: A multicenter, ambispective cohort study including 26 centers across India was conducted. Data from a pre-COVID-19 period (March 1 to August 31, 2019) were collected retrospectively and collected ambispectively for a specified COVID-19 period (March 1 to August 31, 2020). The study was registered with the Clinical Trial Registry India (CTRI/2020/11/029143). Results: Data from 555 patients were included for analysis: pre-COVID-19 (n = 334) and COVID-19 (n = 221). Males were more commonly affected during both periods (male:female, 2:1). Gastroenteritis was the most frequent antecedent event in 2019 (17.4%), whereas fever was the most common event in 2020 (10.7%). Paraparesis (21.3% versus [vs.] 9.3%, P = 0.001) and sensory involvement (51.1% vs. 41.3%; P = 0.023) were more common during COVID-19 in 2020, whereas back pain (26.3% vs. 18.4%; P = 0.032) and bowel symptoms (20.7% vs. 13.7%; P = 0.024) were more frequent in the pre-COVID period. There was no difference in clinical outcomes between the two groups in terms of GBS disability score at discharge and 3 months after discharge. Independent predictors of disability in the pre-COVID period included areflexia/hyporeflexia, the requirementfor intubation, and time to bulbar weakness; in the COVID-19 period, independent predictors included time from onset to admission, intubation, and intubation requirement. The mortality rate was 2.3% during the entire study period (13/555 cases). Discussion: Results of this study revealed an overall reduction in the frequency of GBS during the pandemic. The lockdown likely reduced the risk for antecedent infections due to social distancing and improved hygiene, which may have resulted in the reduction of the frequency of GBS.

2.
East Asian Arch Psychiatry ; 31(3): 81-83, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34588318

RESUMO

Lurasidone is used for treatment of bipolar depression in adults and adolescents. Lurasidone-associated manic switch has been reported in adults but not yet in adolescents. We report a case of lurasidone-induced manic switch in a male adolescent treated for bipolar I depression. Five days after adding lurasidone to his regimen (sodium valproate and olanzapine), our patient became manic with psychotic features. After discontinuation of lurasidone, he was stabilised with electroconvulsive therapy, and the medication was switched to a lithium-quetiapine combination. This case highlights the potential risk of lurasidone-induced manic switch in adolescents with bipolar depression.


Assuntos
Antipsicóticos/efeitos adversos , Transtorno Bipolar/tratamento farmacológico , Cloridrato de Lurasidona/efeitos adversos , Mania/induzido quimicamente , Adolescente , Transtorno Bipolar/complicações , Quimioterapia Combinada , Humanos , Compostos de Lítio/uso terapêutico , Masculino , Mania/complicações , Olanzapina/uso terapêutico , Fumarato de Quetiapina/uso terapêutico , Ácido Valproico/uso terapêutico
3.
J Healthc Qual Res ; 35(2): 117-122, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32229102

RESUMO

BACKGROUND AND OBJECTIVE: Leadership communicates purpose and innovative ways to thrive for performance. Leadership support influences and impacts operational excellence in the health sector as a patient-centered operation, with effective management, excellence framework, challenges and constraints, teamwork and value stream mapping. It is hypothesized that: (1) perceived leadership support will positively correlate with perceived operational excellence (Patient-centered Operations, Effective Resource Management, Excellence framework, Eliminating Challenges or Constraints, Team Work, Value Stream Mapping) and (2) the correlation would be highest with Patient-centered Operations. The aim of this study was to examine the relationship between leadership support and operational excellence in the health care sector among a selected group of healthcare managers. MATERIALS AND METHOD: A correlation study between leadership support and operational excellence was designed for a group of health care managers (n=80) from eight hospitals in Kerala, South India. The selection of executives was from NABH accredited hospitals from districts with a minimum of four NABH accredited hospital. A survey was sent to a selected study sample. The respondents were cooperative and provided responses on perceived leadership support for operational excellence. RESULTS: Factors of leadership support correlated to operational excellence. CONCLUSION: In the health care sector, leadership support for patient-centered operations helps achieve operational excellence.


Assuntos
Setor de Assistência à Saúde/organização & administração , Setor de Assistência à Saúde/normas , Administração de Serviços de Saúde/normas , Liderança , Correlação de Dados , Humanos , Índia , Assistência Centrada no Paciente
4.
Andrologia ; 50(6): e13029, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29740849

RESUMO

We studied the changes in mRNA expressions of influx and efflux transporters, blood-testis-barrier proteins (BTB) and key apoptotic genes in the testis of rats coadministered with nicotine and atorvastatin. Rats were divided into four groups: (i) control, (ii) atorvastatin (10 mg/kg b.wt), (iii) nicotine (0.6 mg/kg b.wt) and (iv) atorvastatin (10 mg/kg b.wt) + nicotine (0.6 mg/kg b.wt). Atorvastatin was given by oral intubation and nicotine by intraperitoneal injection. After 60 days of treatment, expressions of key apoptotic genes involved in both intrinsic and extrinsic pathways; solute carrier influx transporters SLCOB1, SLC22A1 and efflux transporter ABCB1 associated with transport of atorvastatin and nicotine, and proteins of BTB were assayed. Nicotine administration activated apoptosis and downregulated SLCOB1, which transport atorvastatin. Atorvastatin administration suppressed apoptotic pathway and downregulated SLC22A1, transporter of nicotine. Coadministration of atorvastatin with nicotine downregulated expressions of apoptotic genes. The combined administration of atorvastatin and nicotine reduced the influx of both atorvastatin and nicotine and enhanced the efflux of these drugs thereby altering the microenvironment of testis and improving testicular function. We conclude that atorvastatin-mediated alterations of BTB and drug transporters might have played a significant role in ameliorating nicotine-induced testicular toxicity.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Atorvastatina/farmacologia , Barreira Hematotesticular , Proteínas da Membrana Plasmática de Transporte de Catecolaminas/metabolismo , Nicotina/antagonistas & inibidores , Testículo , Animais , Barreira Hematotesticular/efeitos dos fármacos , Barreira Hematotesticular/metabolismo , Masculino , Nicotina/toxicidade , Ratos , Ratos Sprague-Dawley , Proteínas Carreadoras de Solutos/metabolismo , Testículo/efeitos dos fármacos , Testículo/metabolismo
5.
Indian J Cancer ; 54(1): 301-304, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29199709

RESUMO

CONTEXT: The hypofractionated stereotactic body radiation therapy (SBRT) has emerged as a safe and effective treatment modality for early-stage nonsmall cell lung carcinoma. AIMS: An audit SBRT in primary lung cancer treated in our center with and without an active breath coordinator (ABC) was undertaken to evaluate its impact on target volumes and clinical outcomes. SETTINGS AND DESIGN: This was an observational study. MATERIALS AND METHODS: Nine patients with lung carcinoma were treated from January 2014 to August 2016. Five patients were simulated using ABC and four patients with free breathing. Volumetric modulated arc therapy plans were generated using Monaco treatment planning software. Three patients were treated with a dose of 54 Gy in three fractions and six patients with a dose of 48 Gy in four fractions. STATISTICAL ANALYSIS USED: The statistical analysis was performed using Kaplan-Meier survival. RESULTS: The mean planning target volumes (PTV) in ABC and free breathing groups were 42.19cc and 60.17cc, respectively. The mean volume of lung receiving 20, 10, and 5 Gy (V20, V10and V5) in ABC group were 5.37cc, 10.49cc, and 18.45cc whereas in free breathing 6.63cc, 12.74cc, and 20.64cc, respectively. At a median follow-up of 18 months, there were three local recurrences. No significant toxicity occurred in our series. CONCLUSION: Our initial results show that SBRT is well tolerated with good local control. Although the PTV volume and irradiated normal lung volume was higher in this group compared to ABC group, this did not translate to any added clinical toxicity.


Assuntos
Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/radioterapia , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/radioterapia , Idoso , Feminino , Humanos , Pulmão/fisiopatologia , Pulmão/efeitos da radiação , Neoplasias Pulmonares/fisiopatologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Radiocirurgia/efeitos adversos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada/efeitos adversos , Mecânica Respiratória , Resultado do Tratamento
6.
Neuroscience ; 322: 370-6, 2016 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-26944604

RESUMO

Recent experimental and modeling studies on the lateral amygdala (LA) have implicated intrinsic excitability and competitive synaptic interactions among principal neurons (PNs) in the formation of auditory fear memories. The present modeling studies, conducted over an expanded range of intrinsic excitability in the network, revealed that only excitable PNs that received tone inputs participate in the competition. Strikingly, the number of model PNs integrated into the fear memory trace remained constant despite the much larger range considered, and model runs highlighted several conditioning-induced tone responsive characteristics of the various PN populations. Furthermore, these studies showed that although excitation was important, disynaptic inhibition among PNs is the dominant mechanism that keeps the number of plastic PNs stable despite large variations in the network's excitability. Finally, we found that the overall level of inhibition in the model network determines the number of projection cells integrated into the fear memory trace.


Assuntos
Tonsila do Cerebelo/fisiologia , Simulação por Computador , Medo/fisiologia , Memória/fisiologia , Modelos Neurológicos , Neurônios/fisiologia , Potenciais de Ação/fisiologia , Animais , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Plasticidade Neuronal/fisiologia
7.
Hum Exp Toxicol ; 35(2): 205-12, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25805601

RESUMO

Virgin coconut oil (VCO) is an unrefined kernal oil, prepared from Cocos nucifera L., having substantial nutritional and medicinal value. Experimental studies have suggested its antioxidant, anti-inflammatory, immunostimulatory and hypolipidemic effects. The present study assesses its effect on formalin-induced chronic inflammation and cyclophosphamide (CTX)-induced systemic toxicity in murine models. Oral administration of VCO effectively reduced formalin-induced paw oedema in mice with more or less similar efficacy as that of diclofenac. The CTX-induced hike in blood urea, creatinine, thiobarbituric acid reactive substances (TBARS) and liver marker enzymes in mice was marginally decreased by VCO (8 g/kg body weight) ingestion orally. The liver and kidney catalase, superoxide dismutase and glutathione peroxidase activities, together with cellular glutathione and TBARS levels, were found to be improved in these animals. Overall the study reveals the protective efficacy of VCO against secondary toxicity induced by CTX possibly through its antioxidant and anti-inflammatory properties.


Assuntos
Alquilantes/toxicidade , Ciclofosfamida/antagonistas & inibidores , Ciclofosfamida/toxicidade , Óleos de Plantas/farmacologia , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Antioxidantes/farmacologia , Nitrogênio da Ureia Sanguínea , Óleo de Coco , Creatinina/metabolismo , Suplementos Nutricionais , Edema/patologia , Edema/prevenção & controle , Formaldeído , Inflamação/induzido quimicamente , Inflamação/prevenção & controle , Fígado/enzimologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
9.
Neuroscience ; 224: 249-67, 2012 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-22917618

RESUMO

We propose a novel reduced-order neuronal network modeling framework that includes an enhanced firing rate model and a corresponding synaptic calcium-based synaptic learning rule. Specifically, we propose enhancements to the Wilson-Cowan firing-rate neuron model that permit full spike-frequency adaptation seen in biological lateral amygdala (LA) neurons, while being sufficiently general to accommodate other spike-frequency patterns. We also report a technique to incorporate calcium-dependent plasticity in the synapses of the network using a regression scheme to link firing rate to postsynaptic calcium. Together, the single-cell model and the synaptic learning scheme constitute a general framework to develop computationally efficient neuronal networks that employ biologically realistic synaptic learning. The reduced-order modeling framework was validated using a previously reported biophysical conductance-based neuronal network model of a rodent LA that modeled features of Pavlovian conditioning and extinction of auditory fear (Li et al., 2009). The framework was then used to develop a larger LA network model to investigate the roles of tone and shock distributions and of intrinsic connectivity in auditory fear learning. The model suggested combinations of tone and shock densities that would provide experimental estimates of tone responsive and conditioned cell proportions. Furthermore, it provided several insights including how intrinsic connectivity might help distribute sensory inputs to produce conditioned responses in cells that do not directly receive both tone and shock inputs, and how a balance between potentiation of excitation and inhibition prevents stimulus generalization during fear learning.


Assuntos
Tonsila do Cerebelo/fisiologia , Condicionamento Clássico/fisiologia , Modelos Neurológicos , Modelos Teóricos , Rede Nervosa/fisiologia , Estimulação Acústica , Animais , Inteligência Artificial , Plasticidade Neuronal/fisiologia , Neurônios/fisiologia , Ratos
10.
J Phys Condens Matter ; 24(25): 256004, 2012 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-22634874

RESUMO

The magnetic properties of amorphous Fe-Ni-B based metallic glass nanostructures were investigated. The nanostructures underwent a spin-glass transition at temperatures below 100 K and revealed an irreversible temperature following the linear de Almeida-Thouless dependence. When the nanostructures were cooled below 25 K in a magnetic field, they exhibited an exchange bias effect with enhanced coercivity. The observed onset of exchange bias is associated with the coexistence of the spin-glass phase along with the appearance of another spin-glass phase formed by oxidation of the structurally disordered surface layer, displaying a distinct training effect and cooling field dependence. The latter showed a maximum in exchange bias field and coercivity, which is probably due to competing multiple equivalent spin configurations at the boundary between the two spin-glass phases.

11.
Oncogene ; 31(38): 4182-95, 2012 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-22231446

RESUMO

MicroRNAs (miRNAs) are small non-coding RNAs of ∼20 nt in length that are capable of modulating gene expression post-transcriptionally. Although miRNAs have been implicated in cancer, including breast cancer, the regulation of miRNA transcription and the role of defects in this process in cancer is not well understood. In this study we have mapped the promoters of 93 breast cancer-associated miRNAs, and then looked for associations between DNA methylation of 15 of these promoters and miRNA expression in breast cancer cells. The miRNA promoters with clearest association between DNA methylation and expression included a previously described and a novel promoter of the Hsa-mir-200b cluster. The novel promoter of the Hsa-mir-200b cluster, denoted P2, is located ∼2 kb upstream of the 5' stemloop and maps within a CpG island. P2 has comparable promoter activity to the previously reported promoter (P1), and is able to drive the expression of miR-200b in its endogenous genomic context. DNA methylation of both P1 and P2 was inversely associated with miR-200b expression in eight out of nine breast cancer cell lines, and in vitro methylation of both promoters repressed their activity in reporter assays. In clinical samples, P1 and P2 were differentially methylated with methylation inversely associated with miR-200b expression. P1 was hypermethylated in metastatic lymph nodes compared with matched primary breast tumours whereas P2 hypermethylation was associated with loss of either oestrogen receptor or progesterone receptor. Hypomethylation of P2 was associated with gain of HER2 and androgen receptor expression. These data suggest an association between miR-200b regulation and breast cancer subtype and a potential use of DNA methylation of miRNA promoters as a component of a suite of breast cancer biomarkers.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Metilação de DNA , MicroRNAs/genética , Regiões Promotoras Genéticas , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Mapeamento Cromossômico , Ilhas de CpG , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Família Multigênica , Metástase Neoplásica , Receptor ErbB-2/genética , Receptores de Estrogênio/genética , Receptores de Progesterona/genética , Reprodutibilidade dos Testes , Sítio de Iniciação de Transcrição
12.
Indian J Med Ethics ; 8(2): 102-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22106620

RESUMO

This paper identifies some ethical concerns regarding the Revised National Tuberculosis Control Programme (RNTCP). Only 10% of those with chest symptoms visiting public health facilities get specific treatment as they are diagnosed with TB. The remaining 90% who suffer from non-TB diseases are not given scientific treatment. This compartmental approach denies treatment to millions of people with chest symptoms. It has also eroded the popularity of public health facilities. Second, though 87% of those diagnosed on the basis of x-ray alone are unlikely to have TB, such unethical wrong diagnoses continue to be carried out under the TB programme. Still worse, the RNTCP's expectation that only half of TB cases should be smear positive effectively permits up to 50% of diagnoses to be wrong. The actual extent of wrong diagnosis is even higher as the majority of people with chest symptoms first visit private health facilities which base their diagnosis almost exclusively on radiological examination. Third, though 25% to 33% of TB cases get cured spontaneously, and at least two-thirds were cured even with incomplete treatment, the RNTCP insists on full treatment for all TB cases. This over-treatment is unethical, wasteful and also tantamount to scientific dishonesty. Studies to identify different categories of cases (those needing full treatment, short treatment or no treatment) have not been attempted. The introduction (under the RNTCP) of the "success rate"in preference to the well recognised "cure rate" was unethical and unwarranted. "Crying wolf" over Multiple Drug Resistant (MDR) TB to justify DOTS when there is no apparent alarming increase in the incidence of initial MDR tuberculosis cases is also questionable. Other ethical concerns about the RNTCP include the irrational choice of districts leading to exclusion of those that need the services most; exclusion of diagnosed patients from the DOTS scheme, and exclusion from treatment on non-medical grounds. Such exclusions can be up to 58% of TB cases.


Assuntos
Programas Nacionais de Saúde/ética , Avaliação das Necessidades , Qualidade da Assistência à Saúde/ética , Tuberculose/prevenção & controle , Antituberculosos/uso terapêutico , Controle de Doenças Transmissíveis/organização & administração , Erros de Diagnóstico/ética , Terapia Diretamente Observada/ética , Humanos , Prescrição Inadequada/ética , Índia , Programas Nacionais de Saúde/organização & administração , Qualidade da Assistência à Saúde/organização & administração , Tuberculose/diagnóstico , Tuberculose/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/prevenção & controle
13.
Neuroscience ; 158(4): 1266-76, 2009 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-19084053

RESUMO

Chronic cocaine administration causes instability in extracellular glutamate in the nucleus accumbens that is thought to contribute to the vulnerability to relapse. A computational framework was developed to model glutamate in the extracellular space, including synaptic and nonsynaptic glutamate release, glutamate elimination by glutamate transporters and diffusion, and negative feedback on synaptic release via metabotropic glutamate receptors (mGluR2/3). This framework was used to optimize the geometry of the glial sheath surrounding excitatory synapses, and by inserting physiological values, accounted for known stable extracellular, extrasynaptic concentrations of glutamate measured by microdialysis and glutamatergic tone on mGluR2/3. By using experimental values for cocaine-induced reductions in cystine-glutamate exchange and mGluR2/3 signaling, and by predicting the down-regulation of glutamate transporters, the computational model successfully represented the experimentally observed increase in glutamate that is seen in rats during cocaine-seeking. This model provides a mathematical framework for describing how pharmacological or pathological conditions influence glutamate transmission measured by microdialysis.


Assuntos
Anestésicos Locais/farmacologia , Cocaína/farmacologia , Simulação por Computador , Líquido Extracelular/efeitos dos fármacos , Ácido Glutâmico/metabolismo , Modelos Biológicos , Núcleo Accumbens/efeitos dos fármacos , Potenciais de Ação/fisiologia , Sistema X-AG de Transporte de Aminoácidos/deficiência , Animais , Cistina/metabolismo , Líquido Extracelular/metabolismo , Neuroglia/metabolismo , Neurônios/fisiologia , Núcleo Accumbens/metabolismo , Ratos , Receptores de Glutamato/fisiologia , Sinapses/fisiologia , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/fisiologia
14.
ISA Trans ; 43(4): 509-25, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15535391

RESUMO

The nonlinear dynamics of a flexible two link manipulator presents a challenging modeling and control problem with its lumped actuator dynamics coupled with distributed link dynamics. Issues related to modeling uncertainty and control robustness as well as a good understanding of the experimental issues are essential for advanced modeling and control for such systems. This paper reports some of the advanced modeling, control, and experimental issues for a flexible two link manipulator, including some novel approaches developed by the authors.


Assuntos
Algoritmos , Retroalimentação , Modelos Teóricos , Robótica/métodos , Simulação por Computador , Elasticidade , Movimento (Física) , Robótica/instrumentação , Estresse Mecânico
15.
J Dairy Sci ; 87(9): 2831-8, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15375041

RESUMO

The objective of this study was to evaluate the effects of cheese-making technologies, including homogenization of cream, ultrafiltration, and vacuum condensing of milk, on the retention of salt in Cheddar cheese. One part of pasteurized, separated milk (0.58% fat) was ultrafiltered (55 degrees C, 16.0% protein), another vacuum condensed (12.5% protein), and the third was not concentrated. Cheddar cheese was manufactured using 6 treatments by standardizing unconcentrated milk to a casein-to-fat ratio of 0.74 with unhomogenized 35% fat cream (C), homogenized (6.9 MPa/3.5 MPa) 35% fat cream (CH), ultrafiltered milk and unhomogenized cream (UF), ultrafiltered milk and homogenized cream (UFH), condensed milk and unhomogenized cream (CM), and condensed milk and homogenized cream (CMH). Treatments C and CH had 3.7% fat and 3.5% protein, and the respective values for the remaining treatments were 4.9 and 4.6. The milled curd was dry salted at 2.7% by weight. The salt content of the cheeses receiving homogenization treatment was higher at 1.83 and 1.70% for CH and UFH, respectively, compared with their corresponding controls at 1.33%. The salt content in cheeses from CMH was 1.64% and was not affected by homogenization. Salt retention in C increased from 41.7 to 59.2% in CH, and in UF it increased from 42.5 to 54.5% in UFH. There was a corresponding decrease in the salt content of whey from these cheeses.


Assuntos
Queijo/análise , Manipulação de Alimentos/métodos , Cloreto de Sódio/análise , Animais , Caseínas/análise , Tecnologia de Alimentos , Lipídeos/análise , Leite/química , Proteínas do Leite/análise , Ultrafiltração , Proteínas do Soro do Leite
16.
Pigment Cell Res ; 14(3): 206-9, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11434569

RESUMO

MSG1 is a 27 kDa nuclear protein that is expressed strongly in melanotic B16 melanoma cells but very weakly in amelanotic B16 cells. Transient expression of B16 cells with an expression vector for MSG1 resulted in an increase in levels of the enzyme dopachrome tautomerase but not tyrosinase, as detected by western blotting. Stable transfection of B16 melanoma cells with plasmids containing the full length MSG1 or its deletion mutants, however, generated cell lines that showed an increase in levels of tyrosinase, dopachrome tautomerase and cellular melanin when compared with control transfected cells. Our results suggest that MSG1 plays an important role in melanogenesis, by regulating the levels of the enzymes of the pigmentary system via tyrosinase and dopachrome tautomerase.


Assuntos
Melaninas/biossíntese , Melanócitos/fisiologia , Melanoma Experimental/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas Nucleares/fisiologia , Ativação Transcricional , Animais , Proteínas Reguladoras de Apoptose , Northern Blotting , Western Blotting , Oxirredutases Intramoleculares/metabolismo , Melanoma Experimental/genética , Camundongos , Monofenol Mono-Oxigenase/metabolismo , Mutação , Plasmídeos/metabolismo , Estrutura Terciária de Proteína , Transativadores , Transfecção , Células Tumorais Cultivadas
17.
Adolescence ; 36(141): 153-62, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11407631

RESUMO

This study examined the relationship between the quality of adjustment in adolescents and a set of psychiatric diagnoses, personality traits, parental bonding, and social support variables. One hundred fifty adolescents were administered the Millon Adolescent Personality Inventory, the Parental Bonding Questionnaire, the Social Support Questionnaire, and the Diagnostic Interview for Children and Adolescents. A neural network approach was then utilized, and it was found that several of the variables (e.g., Major Depressive Disorder, Conduct Disorder, and Societal Conformity) had a significant role in classifying adolescents into three groups: maladjusted, nominally adjusted, and well-adjusted.


Assuntos
Comportamento do Adolescente/psicologia , Rede Nervosa/fisiologia , Ajustamento Social , Adolescente , Feminino , Humanos , Masculino
18.
Anal Chem ; 73(7): 1408-15, 2001 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11321288

RESUMO

The application of trilinear decomposition (TLD) to the analysis of fluorescence excitation-emission matrices of mixtures of polycyclic aromatic hydrocarbons (PAHs) is described. The variables constituting the third-order tensor are excitation wavelength, emission wavelength, and concentration of a fluorescence quencher (nitromethane). The addition of a quencher to PAH mixtures selectively reduces the fluorescence intensity of mixture components according to the Stern-Volmer equation. TLD allows the three-way matrix to be decomposed to give unique solutions for the excitation spectrum, emission spectrum, and quenching profiles for each component. The availability of spectra and calculated Stern-Volmer constants can aid in the identification of unknown components. Preprocessing of the data to correct for Rayleigh/Raman scatter and primary absorption by the quencher is necessary. Both three-component (anthracene, pyrene, 1-methylpyrene) and four-component (fluoranthene, anthracene, pyrene, 2,3-benzofluorene) synthetic mixtures are successfully resolved by TLD using quencher concentrations up to 100 mM. Results are compared using both alternating least-squares and direct trilinear decomposition algorithms. The reproducibility of extracted Stern-Volmer constants is determined from replicate experiments. To illustrate the application of TLD to a real sample, a chromatographic cut from the analysis of a light gas oil sample was used. Analysis of the TLD extracted spectra and quenching constants suggests the presence of three classes of polycyclic aromatic hydrocarbons consistent with data from a second dimension of chromatography and mass spectrometry.

19.
J Nutr Biochem ; 12(1): 7-13, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11179856

RESUMO

Several mechanisms have been proposed to explain the anti-arrhythmic effects of n-3 polyunsaturated fatty acids. One mechanism is the effect of modifying cell membrane phospholipid and their subsequent effect on intracellular cell signaling via the second messengers, Ins(1,4,5)P(3) and diacylglycerol. Isolated cardiac myocytes from adult pig hearts were used to investigate the effect of n-3 polyunsaturated fatty acids, eicosapentaenoic acid and docosahexaenoic acid, on the inositol phosphate metabolism and protein kinase C activity. Adult porcine cardiac myocytes were grown in media supplemented with 400 µM arachidonic acid, eicosapentaenoic acid and docosahexaenoic acid. After 24 hr, fatty acid analyses of total lipids by TLC in supplemented cells showed that eicosapentaenoic acid and docosahexaenoic acid were selectively incorporated into the phosphatidylinositol fraction. In the diacylglycerol fraction, there was a small incorporation of both eicosapentaenoic acid and docosahexaenoic acid but it was not significantly different from that of controls. To study the effect of membrane phospholipid modification on the phospholipase C mediated inositol lipid cycle, cardiac myocytes were labeled with 4µCi/ml myo-[2-(3)H]Ins for 48 hr. After stimulation with epinephrine and phenylephrine (alpha-receptor agonist) the water soluble [(3)H]Ins products were separated by chromatography on Dowex AG 1-X8 and measured by scintillation counting. After stimulation, the levels of [(3)H]Ins(1,4,5)P(3) and [(3)H]Ins(1,3,4,5)P(4) in eicosapentaenoic acid and docosahexaenoic acid supplemented myocytes were significantly reduced (P < 0.05) compared to arachidonic acid supplemented myocytes. Similarly, eicosapentaenoic acid and docosahexaenoic acid supplemented cells had reduced levels of protein kinase C activity after stimulation compared to arachidonic acid supplemented cells. From these experiments, it is evident that n-3 PUFA supplementation modulates intracellular cell signaling suggesting a possible anti-arrhythmic mechanism.

20.
Indian J Exp Biol ; 39(7): 660-7, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12019759

RESUMO

Feeding of 2% cholesterol diet increased lipid parameters in serum and tissues of rats during a period of one month. In addition to the above, lipid peroxidation also increased and activities of certain enzymes were significantly altered in the tissues. Similar changes were also observed to a greater extent with diets containing 40% by weight of coconut kernel or groundnut with and without 2% cholesterol. The enzymes studied were HMGCoA reductase, AST, ALT and ALP in tissues and serum as the case may be. In general the atherogenic effects were observed more with groundnut containing diets than those with coconut. Even though the oil from the former is mostly unsaturated and that from the latter is mostly saturated, these analytical criteria do not relate to their atherogenic effects. When 5% garlic was incorporated with any of the high fat diets, the lipid parameters, their peroxidation and alterations in enzyme activities were significantly decreased. These results show that garlic contains some principles that counteract the atherogenicity of the above oil seeds.


Assuntos
Arteriosclerose/prevenção & controle , Alho , Animais , Arteriosclerose/etiologia , Colesterol na Dieta/administração & dosagem , Óleo de Coco , Dieta Aterogênica , Gorduras Insaturadas na Dieta/administração & dosagem , Rim/metabolismo , Metabolismo dos Lipídeos , Fígado/enzimologia , Masculino , Miocárdio/metabolismo , Óleos de Plantas/administração & dosagem , Ratos , Ratos Sprague-Dawley
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