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1.
Astrophys J ; 862(1)2018 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-31631897

RESUMO

We present 15 high-mass X-ray binary (HMXB) candidates in the disk of M31 for which we are able to infer compact object type, spectral type of the donor star, and age using multiwavelength observations from NuSTAR, Chandra, and the Hubble Space Telescope. The hard X-ray colors and luminosities from NuSTAR permit the tentative classification of accreting X-ray binary systems by compact object type, distinguishing black hole from neutron star systems. We find hard-state black holes, pulsars, and non-magnetized neutron stars associated with optical point-source counterparts with similar frequency. We also find nine non-magnetized neutron stars coincident with globular clusters and an equal number of pulsars with and without point-source optical counterparts. We perform spectral energy distribution (SED) fitting for the most likely optical counterparts to the HMXB candidates, finding seven likely high-mass stars and one possible red helium-burning star. The remaining seven HMXB optical counterparts have poor SED fits, so their companion stars remain unclassified. Using published star formation histories, we find that the majority of HMXB candidates-X-ray sources with UV-bright point-source optical counterpart candidates-are found in regions with star formation bursts less than 50 Myr ago, and three are associated with young stellar ages (<10Myr). This is consistent with similar studies of HMXB populations in the Magellanic Clouds, M33, NGC 300, and NGC 2403.

2.
J Manipulative Physiol Ther ; 37(8): 586-92, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25200271

RESUMO

OBJECTIVE: The purpose of this study was to investigate if differences in spinal height changes in healthy individuals were observed after a period of spinal unloading using repetitive as compared with sustained lumbar extension exercises. METHODS: This study used a pretest, posttest, crossover design. Asymptomatic participants were recruited using convenience sampling. Thirty-two participants (15 male; 17 female) without back pain were included in the data analysis (mean, 24.4 years; range, 20-41 years). Participants performed sustained or repetitive prone lumbar extension exercises after 1 hour of sustained spinal unloading. Spinal height was measured using a stadiometer before and after the repetitive and sustained prone lumbar extension exercises. RESULTS: Paired t tests revealed no significant difference in spine height after repetitive (P = .774) or sustained (P = .545) prone lumbar extension after a period of spinal unloading. No significant difference between spinal height changes occurred between sustained (mean [SD], -0.28 [2.59] mm) and repetitive (mean [SD], -0.12 [2.42] mm) lumbar extension (P = .756). CONCLUSION: In this group of asymptomatic individuals, sustained and repetitive lumbar extension exercises did not appear to affect spinal height after a period of spinal unloading.


Assuntos
Exercício Físico , Coluna Vertebral/anatomia & histologia , Coluna Vertebral/fisiologia , Adulto , Estudos Cross-Over , Feminino , Humanos , Região Lombossacral , Masculino , Decúbito Ventral , Suporte de Carga , Adulto Jovem
3.
Behav Brain Res ; 217(2): 416-23, 2011 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-21074571

RESUMO

INTRODUCTION: Cognitive and attentional deficits in schizophrenia include impairment of the sensorimotor filter as measured by prepulse inhibition (PPI). In this way, the study of animals that naturally present low PPI responses could be a useful approach for screening new antipsychotic drugs. Several pieces of evidence suggest that dopamine and nitric oxide (NO) can modulate PPI but their role in those animals is unknown. OBJECTIVES: The aim of this study was to investigate the role of dopamine and NO in Wistar rats with naturally low PPI response. METHODS: Male Wistar rats with low PPI responses received an i.p. injection of the antipsychotics haloperidol (0.1, 0.3 or 1mg/kg) or clozapine (0.5, 1.5 or 5mg/kg), the anxiolytic diazepam (1 or 3mg/kg) or the NO synthase (NOS) inhibitors, N(G)- nitro-l-arginine (l-NOARG; 40mg/kg, acutely or sub-chronically) or 7-Nitroindazole (7-NI; 3, 10 or 30mg/kg). All animals were submitted to the PPI test 1h after injection. Striatal and cortical dopamine, DOPAC, and noradrenaline levels of rats with low PPI responses were compared to rats with normal PPI responses. RESULTS: We found increased levels of catecholamines on the striatum and prefrontal cortex of Wistar rats with low PPI. In these animals, both antipsychotics, typical and atypical, and NOS inhibitors significantly increased PPI. CONCLUSION: Taken together, our findings suggest that the low PPI phenotype may be driven by an overactive catecholamine system. Additionally, our results corroborate the hypothesis of dopamine and NO interaction on PPI modulation and suggest that Wistar rats with low PPI may represent an interesting non-pharmacological model to evaluate new potential antipsychotics.


Assuntos
Inibidores Enzimáticos/farmacologia , Indazóis/farmacologia , Inibição Psicológica , Nitroarginina/farmacologia , Reflexo de Sobressalto/efeitos dos fármacos , Estimulação Acústica/efeitos adversos , Análise de Variância , Animais , Anticonvulsivantes/farmacologia , Comportamento Animal/efeitos dos fármacos , Monoaminas Biogênicas/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Diazepam/farmacologia , Antagonistas de Dopamina/farmacologia , Relação Dose-Resposta a Droga , Interações Medicamentosas , Comportamento Exploratório/efeitos dos fármacos , Haloperidol/farmacologia , Masculino , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Ratos , Ratos Wistar
4.
Cell Mol Neurobiol ; 25(2): 371-92, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16047547

RESUMO

The present review paper describes results indicating the influence of nitric oxide (NO) on motor control. Our last studies showed that systemic injections of low doses of inhibitors of NO synthase (NOS), the enzyme responsible for NO formation, induce anxiolytic effects in the elevated plus maze whereas higher doses decrease maze exploration. Also, NOS inhibitors decrease locomotion and rearing in an open field arena. These results may involve motor effects of this compounds, since inhibitors of NOS, NG-nitro-L-arginine (L-NOARG), N(G)-nitro-L-arginine methylester (L-NAME), N(G)-monomethyl-L-arginine (L-NMMA), and 7-Nitroindazole (7-NIO), induced catalepsy in mice. This effect was also found in rats after systemic, intracebroventricular or intrastriatal administration. Acute administration of L-NOARG has an additive cataleptic effect with haloperidol, a dopamine D2 antagonist. The catalepsy is also potentiated by WAY 100135 (5-HT1a receptor antagonist), ketanserin (5HT2a and alfal adrenergic receptor antagonist), and ritanserin (5-HT2a and 5HT2c receptor antagonist). Atropine sulfate and biperiden, antimuscarinic drugs, block L-NOARG-induced catalepsy in mice. L-NOARG subchronic administration in mice induces rapid tolerance (3 days) to its cataleptic effects. It also produces cross-tolerance to haloperidol-induced catalepsy. After subchronic L-NOARG treatment there is an increase in the density NADPH-d positive neurons in the dorsal part of nucleus caudate-putamen, nucleus accumbens, and tegmental pedunculupontinus nucleus. In contrast, this treatment decreases NADPH-d neuronal number in the substantia nigra compacta. Considering these results we suggest that (i) NO may modulate motor behavior, probably by interfering with dopaminergic, serotonergic, and cholinergic neurotransmission in the striatum; (ii) Subchronic NO synthesis inhibition induces plastic changes in NO-producing neurons in brain areas related to motor control and causes cross-tolerance to the cataleptic effect of haloperidol, raising the possibility that such treatments could decrease motor side effects associated with antipsychotic medications. Finally, recent studies using experimental Parkinson's disease models suggest an interaction between NO system and neurodegenerative processes in the nigrostriatal pathway. It provides evidence of a protective role of NO. Together, our results indicate that NO may be a key participant on physiological and pathophysiological processes in the nigrostriatal system.


Assuntos
Atividade Motora/fisiologia , Neurônios Motores/fisiologia , Óxido Nítrico/fisiologia , Animais , Comportamento Animal/fisiologia
5.
Psychopharmacology (Berl) ; 181(1): 71-9, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15806417

RESUMO

RATIONALE: Drugs like haloperidol (Hal) that decrease dopamine (DA) neurotransmission in the striatum induce catalepsy in rodents and Parkinson disease-like symptoms in humans. Nitric oxide synthase (NOS) inhibitors interfere with motor activity, disrupting rodent exploratory behavior and inducing catalepsy. Catalepsy induced by NOS inhibitors probably involves striatal DA-mediated neurotransmission. Antioxidants such as ascorbic acid (vitamin C) and alpha-tocopherol (vitamin E) have also been shown to interfere with movement modulation and the DA system. OBJECTIVE: The objective of the study is to investigate if the antioxidants vitamins C and E would influence the catalepsy produced by Hal and NOS inhibitors. METHODS: The effects of the following treatments on catalepsy were examined using the hanging-bar test on male Swiss mice (25-30 g): (1) vitamin C (30-1,000 mg/kg)xHal (1 mg/kg); (2) vitamin C (90-1,000 mg/kg)xN (G)-nitro-L: -arginine (LNOARG, 10 and 40 mg/kg); (3) vitamin C (300 mg/kg)xN (G)-nitro-L: -arginine methylester (LNAME, 20-80 mg/kg); (4) vitamin C (300 mg/kg) x 7-nitroindazole (7NI, 3-50 mg/kg); (5) vitamin C (90 mg/kg i.p.) x LNOARG [40 mg/kg twice a day during 4 days (subchronic treatment)]; (7) vitamin E (3-100 mg/kg) x Hal (1 mg/kg); and (6) vitamin E (3-100 mg/kg) x LNOARG (40 mg/kg). RESULTS: Vitamin C enhanced the catalepsy produced by NOS inhibitors and Hal. Treatment with vitamin C did not affect tolerance to LNOARG cataleptic effect induced by subchronic treatment. Vitamin E potentiated the catalepsy induced by LNOARG at all doses tested; in contrast, catalepsy induced by Hal was enhanced only by the dose of 100 mg/kg. CONCLUSIONS: Results support an involvement of dopaminergic and nitrergic systems in motor behavior control and provide compelling evidence that combined administration of the antioxidants vitamins C and E with either Hal or NOS inhibitors exacerbates extrapyramidal effects. Further studies are needed to assess possible clinical implications of these findings.


Assuntos
Ácido Ascórbico/farmacologia , Catalepsia/induzido quimicamente , Antagonistas de Dopamina/farmacologia , Nitroarginina/farmacologia , alfa-Tocoferol/farmacologia , Animais , Catalepsia/patologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Tolerância a Medicamentos , Inibidores Enzimáticos/farmacologia , Haloperidol/farmacologia , Indazóis/farmacologia , Masculino , Camundongos , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Fatores de Tempo , Vitaminas/farmacologia
6.
J Med Virol ; 61(2): 251-8, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10797382

RESUMO

Because of the considerable impact of human cytomegalovirus (HCMV) infection, sensitive, specific, and standardized methods are required for rapid and accurate evaluation of viral load in monitoring transplant recipients. The aim of the present study was to evaluate the usefulness of a multiplex polymerase chain reaction (PCR) for the coamplification of HCMV-DNA and beta-globin genomic sequence in polymorphonuclear leukocytes (PMNL). Analysis and quantification of PCR products were carried out by a DNA enzyme immunoassay (DEIA), which is based on the hybridization of amplified DNA with a single-stranded DNA probe, which coats microtitre wells. Colorimetric detection of the DNA-antibody complex was carried out and optical density (O.D.) was recorded at 450/630 nm. To quantify HCMV/DNA load, a standard curve to which samples O.D. refer was obtained by amplifying serial dilutions of recombinant PGEM-3Z plasmid DNA containing a genomic fragment of glycoprotein B. 340 PMNL specimens from 102 solid organ recipients were tested for the detection of pp65 antigen and HCMV-DNA. The results showed a good correlation between viral load and clinical symptoms of HCMV infection; high specificity and predictive values for HCMV disease were found by PCR, using a cut-off limit of 10(3) genomic copies per 2 x 10(5) PMNL. These findings indicate that the system described is an efficient and reproducible diagnostic method easy to apply for routine diagnosis and therapeutic monitoring of transplanted patients.


Assuntos
Infecções por Citomegalovirus/virologia , Citomegalovirus/isolamento & purificação , Transplante de Órgãos/efeitos adversos , Reação em Cadeia da Polimerase/métodos , Antígenos Virais/sangue , Southern Blotting , Citomegalovirus/genética , Infecções por Citomegalovirus/sangue , Infecções por Citomegalovirus/epidemiologia , Proteínas do Citoesqueleto , DNA Viral/análise , DNA Viral/imunologia , Humanos , Técnicas Imunoenzimáticas , Incidência , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/virologia , Proteínas dos Microfilamentos , Fosfoproteínas/sangue , Plasmídeos , Valor Preditivo dos Testes , Carga Viral
7.
Rev Lat Am Enfermagem ; 7(5): 121-6, 1999 Dec.
Artigo em Português | MEDLINE | ID: mdl-10876557

RESUMO

This paper emphasizes the creation and application of a KIT for the communication of occupational accidents with puncture-cutting objects to the Municipal Health Bureau from the city of Ribeirão Preto. It is an essential instrument for the health care services directed to all the employees of the Health Units. It also evidences the notification and the beginning of the prevention of occupational diseases, being a highly useful instrument whenever any accident occurs. The creation of this KIT enabled the use of prevention measures regarding occupational diseases, culminating with the mobilization of the chiefs and the staff in order to intensify preventive procedures.


Assuntos
Acidentes de Trabalho , Documentação , Ferimentos Penetrantes Produzidos por Agulha/diagnóstico , Gestão de Riscos/métodos , Brasil , Notificação de Doenças , Humanos , Controle de Infecções/métodos
8.
J Med Virol ; 53(3): 189-95, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9365881

RESUMO

The use of sensitive and specific methods for rapid and reliable diagnosis is required due to the considerable impact of human cytomegalovirus (HCMV) in organ transplant recipients. For this purpose the demonstration of the presence of viral antigens in peripheral blood leukocytes (PMNLs) and of viral nucleic acids in the same cells or in sera would seem to be of valid support. The present study was designed to test pp65 antigen, HCMV DNA and HCMV late mRNA in order to provide clinical information for the management of the infection. Fifty solid organ recipients were monitored for six months after transplant. The data obtained from the various tests were analysed from the first evidence of HCMV infection revealed by positive antigenaemia and/or DNA-polymerase chain reaction (PCR). In 3 asymptomatic and in 7 symptomatic patients, PCR became positive 1-2 weeks before antigenaemia but PCR did not discriminate the clinical evolution of HCMV infection. The antigenaemia test well correlated to the development of viral infection being positive in all symptomatics and in 31, 2% of asymptomatics. The antigenic load > 100/2 x 10(5) positive cells was always associated with clinical signs of illness. The detection of late mRNA was more indicative of the virus replicative status in the follow-up of patients treated with ganciclovir. In some cases there was evidence, prior to the other two tests, the block of viral replication due to the antiviral therapy and in others the onset of HCMV infection relapse.


Assuntos
Infecções por Citomegalovirus/diagnóstico , Transplante de Órgãos/efeitos adversos , Fosfoproteínas/sangue , RNA Viral/sangue , Proteínas da Matriz Viral/sangue , Antígenos Virais/sangue , Antígenos Virais/imunologia , Infecções por Citomegalovirus/sangue , Infecções por Citomegalovirus/etiologia , Estudos de Avaliação como Assunto , Seguimentos , Humanos , Transplante de Rim/efeitos adversos , Leucócitos Mononucleares/virologia , Transplante de Fígado/efeitos adversos , Transplante de Pulmão/efeitos adversos , Fosfoproteínas/imunologia , Reação em Cadeia da Polimerase , RNA Mensageiro , Proteínas da Matriz Viral/imunologia
9.
Eur J Nucl Med ; 4(1): 43-8, 1979 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-583037

RESUMO

201Tl-chloride, which has a metabolic behaviour similar to that of potassium and cesium, has been used in 68 patients for the evaluation of thyroid nodules previously recognized as "cold" on 131I or 99mTc scans. All patients were re-examined with gamma-camera and/or sequential scintigraphic recordings during 60 min after i.v. administration of thallium. In some cases, simultaneous imaging and integral digital plot with 131I or 99mTc and 201Tl were performed. In all 12 malignant nodules, 201 Tl has showed a high uptake, while it did not concentrate in 47 benign nodules (cystic or macrofollicular adenomas); thallium uptake was nevertheless found in 10 solid neoformations in which histological pictures were negative for malignancy or atypical lesions. The computerized study of the 201Tl intranodular concentration, with the analysis of its dynamic function curves, seems to offer further possibility in differentiating and in a more objective evaluation of the "cold" areas on the thyroid scan.


Assuntos
Adenoma/diagnóstico por imagem , Carcinoma Papilar/diagnóstico por imagem , Radioisótopos , Tálio , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Computadores , Diagnóstico Diferencial , Humanos , Cintilografia , Tálio/metabolismo , Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/metabolismo , Tireoidite Autoimune/diagnóstico por imagem
10.
Ric Clin Lab ; 7(3): 289-95, 1977.
Artigo em Inglês | MEDLINE | ID: mdl-605342

RESUMO

We used 201Tl-chloride for studying and differentiating thyroid areas shown to be 'cold' in previous 131I or 99mTc scanning. We investigated sixteen thyroid neoplasms that were removed surgically shortly afterwards. We found an intense intranodular accumulation of 301T1 in five scintigraphs shown to be of histologically malignant neoplasms, and an intense accumulation also in one of those shown to be histologically benign. We did not detect any 201Tl-chloride accumulation in two cases of thyroiditis; one of these had shown an intense accumulation in a previous 131Cs scintigram.


Assuntos
Tálio , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma Papilar/diagnóstico por imagem , Adenoma/diagnóstico por imagem , Carcinoma/diagnóstico por imagem , Diagnóstico Diferencial , Humanos , Metástase Linfática , Radioisótopos , Cintilografia
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