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1.
Scott Med J ; 57(1): 26-32, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22408212

RESUMO

Prolonged endurance exercise over several days induces increase in extracellular water (ECW). We aimed to investigate an association between the increase in ECW and the change in aldosterone and vasopressin in a multistage ultraendurance triathlon, the 'World Challenge Deca Iron Triathlon' with 10 Ironman triathlons within 10 days. Before and after each Ironman, body mass, ECW, urinary [Na(+)], urinary [K(+)], urinary specific gravity, urinary osmolality and aldosterone and vasopressin in plasma were measured. The 11 finishers completed the total distance of 38 km swimming, 1800 km cycling and 422 km running within 145.5 (18.8) hours and 25 (22) minutes. ECW increased by 0.9 (1.1) L from 14.6 (1.5) L prerace to 15.5 (1.9) L postrace (P < 0.0001). Aldosterone increased from 70.8 (104.5) pg/mL to 102.6 (104.6) pg/mL (P = 0.033); vasopressin remained unchanged. The increase in ECW was related neither to postrace aldosterone nor to postrace vasopressin. In conclusion, ECW and aldosterone increased after this multistage ultraendurance triathlon, but vasopressin did not. The increase in ECW and the increase in aldosterone were not associated.


Assuntos
Aldosterona/sangue , Eletrólitos/urina , Líquido Extracelular/metabolismo , Resistência Física/fisiologia , Esportes/fisiologia , Vasopressinas/sangue , Adulto , Desempenho Atlético , Ciclismo/fisiologia , Composição Corporal/fisiologia , Humanos , Masculino , Músculo Esquelético/metabolismo , Corrida/fisiologia , Natação/fisiologia
2.
Int J Neural Syst ; 32(3): 2250008, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34996341

RESUMO

As a neurodevelopmental pathology, Attention Deficit Hyperactivity Disorder (ADHD) mainly arises during childhood. Persistent patterns of generalized inattention, impulsivity, or hyperactivity characterize ADHD that may persist into adulthood. The conventional diagnosis relies on clinical observational processes yielding high rates of overdiagnosis due to varying interpretations among specialists or missing information. Although several studies have designed objective behavioral features to overcome such an issue, they lack significance. Despite electroencephalography (EEG) analyses extracting alternative biomarkers using signal processing techniques, the nonlinearity and nonstationarity of EEG signals restrain performance and generalization of hand-crafted features. This work proposes a methodology to support ADHD diagnosis by characterizing EEG signals from hidden Markov models (HMM), classifying subjects based on similarity measures for probability functions, and spatially interpreting the results using graphic embeddings of stochastic dynamic models. The methodology learns a single HMM for EEG signal from each patient, so favoring the inter-subject variability. Then, the Probability Product Kernel, specifically developed for assessing the similarity between HMMs, fed a support vector machine that classifies subjects according to their stochastic dynamics. Lastly, the kernel variant of Principal Component Analysis provided a means to visualize the EEG transitions in a two-dimensional space, evidencing dynamic differences between ADHD and Healthy Control children. From the electrophysiological perspective, we recorded EEG under the Stop Signal Task modified with reward levels, which considers cognitive features of interest as insufficient motivational circuits recruitment. The methodology compares the supported diagnosis in two EEG channel setups (whole channel set and channels of interest in frontocentral area) and four frequency bands (Theta, Alpha, Beta rhythms, and a wideband). Results evidence an accuracy rate of 97.0% in the Beta band and in the channels where previous works found error-related negativity events. Such accuracy rate strongly supports the dual pathway hypothesis and motivational deficit concerning the pathophysiology of ADHD. It also demonstrates the utility of joining inhibitory and motivational paradigms with dynamic EEG analysis into a noninvasive and affordable diagnostic tool for ADHD patients.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Adulto , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Ritmo beta/fisiologia , Criança , Eletroencefalografia/métodos , Humanos , Processamento de Sinais Assistido por Computador , Máquina de Vetores de Suporte
3.
Int Immunopharmacol ; 7(8): 1013-24, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17570318

RESUMO

Activation of the high affinity IgE receptor (Fc epsilonRI) through IgE-antigen complexes induces mast cell degranulation, synthesis of lipid mediators and cytokine production. These effects are involved in Type I hypersensitivity reactions and controlling them has been the main objective of many anti-allergic therapies. Here we report that pretreatment of murine bone marrow derived mast cells (BMMC) with super-oxidized solution (SOS) inhibits Fc epsilonRI dependent-beta hexosaminidase and cytokine release. This effect is exerted without altering total protein tyrosine phosphorylation, MAPK activation, cytokine mRNA accumulation or calcium mobilization after Fc epsilonRI triggering. Our data suggest that this neutral pH-SOS acts like a mast cell-membrane stabilizer inhibiting the cell machinery for granule secretion without altering the signal transduction pathways induced by IgE-antigen receptor crosslinking.


Assuntos
Degranulação Celular/efeitos dos fármacos , Citocinas/metabolismo , Peróxido de Hidrogênio/toxicidade , Imunoglobulina E/imunologia , Mastócitos/efeitos dos fármacos , Animais , Western Blotting , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Cálcio/metabolismo , Degranulação Celular/imunologia , Sobrevivência Celular/efeitos dos fármacos , Citocinas/genética , Desinfetantes/toxicidade , Ensaio de Imunoadsorção Enzimática/métodos , Mastócitos/metabolismo , Mastócitos/fisiologia , Camundongos , Camundongos Endogâmicos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fatores de Transcrição NFATC/metabolismo , Fosforilação/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de IgE/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Hipoclorito de Sódio/toxicidade , Tirosina/metabolismo , beta-N-Acetil-Hexosaminidases/metabolismo
4.
J Hosp Infect ; 61(4): 291-9, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16242210

RESUMO

A new super-oxidized water (SOW) product, Microcyn, was tested for in vitro antimicrobial and antiviral activities. The effectiveness of this neutral-pH SOW at killing Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi and Candida albicans in pure culture was evaluated. One millilitre (approximately 10(8)colony-forming units/mL) of each micro-organism was subjected to 9 mL Microcyn or sterile water at room temperature for 30s. Under these conditions, a log(10) reduction factor of 8 in the level of all pathogens occurred in the treatment samples. In addition, results of tests with three batches of Microcyn exposed to Bacillus atrophaeus spores for 5 min demonstrated complete inactivation of the spores within 2-3 min (log(10) reduction factor >4). The effectiveness of Microcyn in reducing human immunodeficiency virus-1 (HIV-1) on hard surfaces (glass) was also evaluated in compliance with Environmental Protection Agency requirements for virucidal claims. After exposure of the tested surfaces to Microcyn for 5 min without agitation, there was a log(10) reduction factor >3 in the viral load as measured by both cytopathic effect and antigen p24 of HIV-1 production in MT-2 cultures. Microcyn activity against adenoviral vector type 5 was also analysed under simulated laboratory in-use conditions with viral suspensions. In order to increase the sensitivity of the test, the fluorescent light emitted by AdGFP-infected cells was measured with the use of a flow cytometer. A log(10) reduction factor >3 in the viral load was achieved after a 5-min exposure to Microcyn under these strict conditions. These results show that Microcyn exerts a wide antimicrobial spectrum with major advantages over acidic SOWs, including neutral pH, lower free active chlorine (51-85 ppm) and long shelf life (1 year).


Assuntos
Desinfetantes/farmacologia , Peróxido de Hidrogênio/farmacologia , Adenoviridae/efeitos dos fármacos , Bactérias/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Linhagem Celular , Contagem de Colônia Microbiana , Efeito Citopatogênico Viral , Citometria de Fluxo , Fluorescência , Proteínas de Fluorescência Verde/análise , Proteínas de Fluorescência Verde/genética , Proteína do Núcleo p24 do HIV/análise , HIV-1/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Esporos Bacterianos/efeitos dos fármacos , Carga Viral
5.
Open Vet J ; 5(2): 138-47, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26623380

RESUMO

In this study we demonstrated that the vaccine candidate against avian influenza virus H5N1 based on the hemagglutinin H5 (HA) fused to the chicken CD154 (HACD) can also be used for differentiating infected from vaccinated animals (DIVA). As the strategy of DIVA requires at least two proteins, we obtained a variant of the nucleoprotein (NP49-375) in E. coli. After its purification by IMAC, the competence of the proteins NP49-375 and HACD as coating antigens in indirect ELISA assays were tested by using the sera of chickens immunized with the proteins HA and HACD and the reference sera from several avian influenza subtypes. Together with these sera, the sera from different species of birds and the sera of chickens infected with other avian viral diseases were analyzed by competition ELISA assays coated with the proteins NP49-375 and HACD. The results showed that the segment CD154 in the chimeric protein HACD did not interfere with the recognition of the molecule HA by its specific antibodies. Also, we observed variable detection levels when the reference sera were analyzed in the ELISA plates coated with the protein NP49-375. Moreover, only the antibodies of the reference serum subtype H5 were detected in the ELISA plates coated with the protein HACD. The competition ELISA assays showed percentages of inhibition of 88-91% for the positives sera and less than 20% for the negative sera. We fixed the cut-off value of these assays at 25%. No antibody detection was observed in the sera from different species of birds or the sera of chickens infected with other avian viral diseases. This study supported the fact that the ELISA assays using the proteins NP49-375 and HACD could be valuable tools for avian influenza surveillance and as a strategy of DIVA for counteracting the highly pathogenic avian influenza virus H5N1 outbreaks.

6.
Int J Tuberc Lung Dis ; 1(4): 339-45, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9432390

RESUMO

SETTING: Laboratories performing sputum smear microscopy for tuberculosis in Benin, Malawi, Nicaragua and Senegal. METHODS: Analysis of computerized laboratory registers to ascertain workload, yield from serial smear examination, and demographic characteristics of examinees. RESULTS: Data from more than 60,000 examinees in 42 laboratories showed that the average number of smears examined per day ranged from 4 to 19 (mean 6) per country. To find one case of tuberculosis, on average 21 smears of suspects were examined (range 8 to 50). Of all cases with ultimately at least one positive result, 87% were already positive on the first examination. Demographic characteristics of cases differed considerably by country and gender. In 35 of 42 laboratories, males were more frequently found to be cases than females, and with increasing age an increasingly larger number of female than male suspects had to be examined to identify one case. CONCLUSIONS: This study demonstrates the usefulness of a standardized recording system for results of acid-fast microscopy in obtaining essential information for program management and on demographic characteristics of persons presenting for examination.


Assuntos
Sistemas de Informação em Laboratório Clínico , Países em Desenvolvimento , Programas de Rastreamento , Sistemas Computadorizados de Registros Médicos , Mycobacterium tuberculosis/isolamento & purificação , Escarro/microbiologia , Tuberculose Pulmonar/epidemiologia , Adolescente , Adulto , Idoso , Técnicas Bacteriológicas , Criança , Comparação Transcultural , Feminino , Humanos , Masculino , Microscopia , Pessoa de Meia-Idade , Garantia da Qualidade dos Cuidados de Saúde , Sistema de Registros/estatística & dados numéricos , Software , Tuberculose Pulmonar/diagnóstico , Carga de Trabalho/estatística & dados numéricos
7.
Arch Cardiol Mex ; 71(2): 136-40, 2001.
Artigo em Espanhol | MEDLINE | ID: mdl-11565305

RESUMO

UNLABELLED: The potential cardioembolic sources for ischemic stroke in patients younger than 40 years could be asymptomatic. The purpose of this study is to justify routine implementation of transesophageal echocardiography (TEE) in the study of young patients with ischemic stroke. MATERIAL AND METHODS: 34 patients younger than 40 years with ischemic stroke were studied with TEE complemented with contrast study, looking for potential cardioembolic sources or intracardiac shunts. RESULTS: 19 patients were male and 15 female with ages between 18-40 years (average 31 years). None had cardiac signs or symptoms. Eleven anomalies were detected in 20 patients (58.8%); of these, only 3 were considered as probably coursing with cardioembolic sources: patent foramen ovale (PFO), mitral valve prolapse, and ventricular enlargement, which were found in 12 patients (35.29%). In patients with cardiovascular anomalies, we found a hypercoagulable state, associated in eight patients with PFO (four patients), two with valvular thickening, and two with valvular nodules. CONCLUSIONS: In patients younger than 40 years with ischemic stroke, TEE is useful in detecting direct and indirect cardiac sources of embolism, even in those patients with unsuspected cardiac disease.


Assuntos
Ecocardiografia Transesofagiana , Acidente Vascular Cerebral/diagnóstico por imagem , Adolescente , Adulto , Fatores Etários , Feminino , Humanos , Masculino
8.
Gac Med Mex ; 136(3): 221-47, 2000.
Artigo em Espanhol | MEDLINE | ID: mdl-10893851

RESUMO

The use of single-cell polymerize chain reaction analysis has allowed for a better understanding of the origin of Hodgkin's disease, Burkitt. The study of the mechanisms regulating apoptosis and the survival of neoplastic clones have opened a whole area of research. The Revised European-American List of lymphoid neoplasms must be presented in a form that facilitates the understanding, learning, and teaching of these disorders. There is a great need for a better definition of the new category of lymphoplasmacytic lymphoma, the variants of mantle cell lymphoma and marginal zone B-cell lymphomas, and the coming of age of the NK-cell lymphomas. Based on current data, it is difficult to determine the site of transplantation in the management of follicular, low-grade non-Hodgkin's lymphoma. These patients remain at risk of relapse after transplantation, mirroring results with conventional therapy. The treatment of aggressive lymphomas remains an area of significant controversy. The Intergroup Study concluded that none of the more recent regimens was superior to CHOP. Recent data suggest that high-dose therapy with consolidative autologous or allogenic transplant may benefit patients with aggressive histology lymphoma who have poor prognostic features.


Assuntos
Linfoma/terapia , Humanos
9.
J Neural Eng ; 8(3): 036026, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21566273

RESUMO

Microelectrode recordings are a valuable tool for assisting localization targets during deep brain stimulation procedures in Parkinson's disease neurosurgery. Attempts to automate and standardize this process have been limited by variability in patient neurophysiology and strong dynamics of microelectrode recordings. In this paper, a methodology for the identification of basal ganglia nuclei is presented that is based on a signal-dependent filter bank method using microelectrode recordings. The method is a customized realization of the discrete wavelet transform via the lifting scheme that is optimally tuned by genetic algorithms. Using this method, unique mother wavelet functions that exhibit an adaptable spectrum to the microelectrode recording dynamic are generated. Additionally, by extracting morphological features from the space-transformed microelectrode recording, it is possible to integrate them into three-dimensional (3D) feature spaces with maximum class separability. Finally, high discriminant feature spaces are fed into basic classifiers to recognize up to four basal nuclei. Comparison with several existing wavelets highlights the characteristics of new mother wavelets. Additionally, classification results show that identification of addressed nuclei in the basal ganglia can be performed with 95% confidence.


Assuntos
Potenciais de Ação , Algoritmos , Gânglios da Base/fisiopatologia , Diagnóstico por Computador/métodos , Eletroencefalografia/métodos , Doença de Parkinson/diagnóstico , Doença de Parkinson/fisiopatologia , Humanos , Sensibilidade e Especificidade , Processamento de Sinais Assistido por Computador
12.
Lancet ; 339(8795): 715-21, 1992 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-1347590

RESUMO

The molecular basis of cancer is now understood to involve activation of dominant oncogenes and inactivation of tumour suppressor genes, and these genetic events may represent novel targets for cancer therapy. This review focuses on the potential use and ethical implications of gene transfer to alter the behaviour of somatic cells in cancer patients. Antisense nucleic acids and ribozymes represent informational drugs that may be used to modulate the expression of selected genes and suppress malignant behaviour in cancer cells. Genetic immunomodulation by introducing genes for cytokines into cancer cells or lymphocytes can stimulate a cytotoxic immune response against the tumour. Gene transfer techniques can be applied to target prodrug activation specifically to tumour cells and also to protect normal tissues against toxic chemotherapy. Gene replacement therapy could even be used to restore the function of defective tumour suppressor genes.


Assuntos
Terapia Genética , Neoplasias/terapia , Animais , Terapia Genética/métodos , Humanos , Neoplasias/genética , Transfecção
13.
Gene Ther ; 1(3): 170-5, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-7584078

RESUMO

Current treatments for metastatic malignant disease are often ineffective. One of the most promising of the selective genetic strategies against cancer is VDEPT (virally directed enzyme prodrug therapy). This uses a viral vector to carry a prodrug-activating enzyme gene into both tumour and normal cells. By linking the foreign gene downstream of tumour-specific transcription units, tumour-specific expression of the foreign enzyme gene can be achieved. We have developed a genetic therapy strategy using VDEPT against cancers that overexpress the oncogene ERBB2. This occurs in approximately one-third of breast and pancreatic tumours (and in a smaller proportion of other tumours) and involves transcriptional up-regulation of the ERBB2 gene with or without gene amplification. We have constructed a chimeric minigene consisting of the proximal ERBB2 promoter linked to the gene encoding cytosine deaminase, an enzyme that can deaminate the prodrug 5-fluorocytosine (5-FC) to form cytotoxic 5-fluorouracil (5-FU). We have constructed a double-copy recombinant retrovirus to deliver the enzyme gene under the control of the ERBB2 promoter into a panel of ERBB2 expression-positive (ERBB2+) and -negative (ERBB2-) pancreatic and breast cell lines. Cytosine deaminase activity was high in ERBB2+ transduced cells but was not detected in ERBB2- transduced cells. Significant cell death was observed in ERBB2+ transduced cells treated with 5-FC whereas ERBB2- cells were not affected. Hence we present a novel gene therapy strategy that is potentially tumour-specific and could be used against a range of tumour types that overexpress the ERBB2 oncogene.


Assuntos
Flucitosina/uso terapêutico , Terapia Genética , Neoplasias/terapia , Pró-Fármacos/uso terapêutico , Sequência de Bases , Biotransformação , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/terapia , Citosina Desaminase , Primers do DNA/genética , Feminino , Flucitosina/farmacocinética , Fluoruracila/farmacocinética , Fluoruracila/uso terapêutico , Genes erbB-2 , Vetores Genéticos , Humanos , Dados de Sequência Molecular , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Nucleosídeo Desaminases/genética , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/terapia , Plasmídeos/genética , Pró-Fármacos/farmacocinética , Retroviridae/genética , Células Tumorais Cultivadas
14.
J Physiol ; 517 ( Pt 1): 95-107, 1999 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-10226152

RESUMO

1. We have combined patch clamp recording with simultaneous [Ca2+]i measurements in single LNCaP cells (a human prostate cancer cell line), to study the activation of Ca2+-permeable channels by two different inducers of apoptosis, ionomycin and serum deprivation. 2. In perforated patch recording, LNCaP cells had a membrane potential of -40 mV and a resting [Ca2+]i of 90 nM. Application of ionomycin at levels that induced apoptosis in these cells (10 microM) produced a biphasic increase in [Ca2+]i. The first rise in [Ca2+]i was due to release of Ca2+ from internal stores and it was associated with a membrane hyperpolarization to -77 mV. The latter was probably due to the activation of high conductance, Ca2+- and voltage-dependent K+ channels (maxi-K). Conversely, the second rise in [Ca2+]i was always preceded by and strictly associated with membrane depolarization and required external Ca2+. Serum deprivation, another inducer of apoptosis, unmasked a voltage-independent Ca2+ permeability as well. 3. A lower concentration of ionomycin (1 microM) did not induce apoptosis, and neither depolarized LNCaP cells nor produced the biphasic increase in [Ca2+]i. However, the first increment in [Ca2+]i due to release from internal Ca2+ stores was evident at this concentration of ionomycin. 4. Simultaneous recordings of [Ca2+]i and ion channel activity in the cell attached configuration of patch clamp revealed a Ca2+-permeable, Ca2+-independent, non-selective cation channel of 23 pS conductance. This channel was activated only during the second increment in [Ca2+]i induced by ionomycin. The absence of serum activated the 23 pS channel as well, albeit at a lower frequency than with ionomycin. 5. Thus, the 23 pS channel can be activated by two unrelated inducers of apoptosis and it could be another Ca2+ influx mechanism in programmed cell death of LNCaP cells.


Assuntos
Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Cálcio/metabolismo , Canais Iônicos/efeitos dos fármacos , Canais Iônicos/metabolismo , Ionomicina/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Sinalização do Cálcio/fisiologia , Meios de Cultura Livres de Soro , Humanos , Transporte de Íons/efeitos dos fármacos , Masculino , Potenciais da Membrana/efeitos dos fármacos , Técnicas de Patch-Clamp , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Células Tumorais Cultivadas
15.
J Neurosci Res ; 78(1): 16-28, 2004 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-15372495

RESUMO

Neurogenesis continues at least in two regions of the mammalian adult brain, the subventricular zone (SVZ) and the subgranular zone in hippocampal dentate gyrus. Neurogenesis in these regions is subjected to physiological regulation and can be modified by pharmacological and pathological events. Here we report the induction of neurogenesis in the SVZ and the differentiation after nigrostriatal pathway lesion along with transcranial magnetic field stimulation (TMFS) in adult rats. Significant numbers of proliferating cells demonstrated by bromodeoxyuridine-positive reaction colocalized with the neuronal marker NeuN were detected bilaterally in the SVZ, and several of these cells also expressed tyrosine hydroxylase. Transplanted chromaffin cells into lesioned animals also induced bilateral appearance of subependymal cells. These results show for the first time that unilateral lesion, transplant, and/or TMFS induce neurogenesis in the SVZ of rats and also that TMFS prevents the motor alterations induced by the lesion.


Assuntos
Diferenciação Celular/fisiologia , Corpo Estriado/citologia , Campos Eletromagnéticos , Neurônios/citologia , Substância Negra/citologia , Animais , Animais Recém-Nascidos , Transplante de Células , Ventrículos Cerebrais/citologia , Ventrículos Cerebrais/fisiologia , Células Cromafins/transplante , Corpo Estriado/fisiologia , Corpo Estriado/transplante , Estimulação Elétrica/métodos , Masculino , Neurônios/fisiologia , Ratos , Ratos Wistar , Substância Negra/fisiologia , Substância Negra/transplante
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