RESUMO

We investigate the properties of time-dependent dissipative solitons for a cubic complex Ginzburg-Landau equation stabilized by nonlinear gradient terms. The separation of initially nearby trajectories in the asymptotic limit is predominantly used to distinguish qualitatively between time-periodic behavior and chaotic localized states. These results are further corroborated by Fourier transforms and time series. Quasiperiodic behavior is obtained as well, but typically over a fairly narrow range of parameter values. For illustration, two examples of nonlinear gradient terms are examined: the Raman term and combinations of the Raman term with dispersion of the nonlinear gain. For small quintic perturbations, it turns out that the chaotic localized states are showing a transition to periodic states, stationary states, or collapse already for a small magnitude of the quintic perturbations. This result indicates that the basin of attraction for chaotic localized states is rather shallow.

RESUMO

We study the time-dependent behavior of dissipative solitons (DSs) stabilized by nonlinear gradient terms. Two cases are investigated: first, the case of the presence of a Raman term, and second, the simultaneous presence of two nonlinear gradient terms, the Raman term and the dispersion of nonlinear gain. As possible types of time-dependence, we find a number of different possibilities including periodic behavior, quasi-periodic behavior, and also chaos. These different types of time-dependence are found to form quite frequently from a window structure of alternating behavior, for example, of periodic and quasi-periodic behaviors. To analyze the time dependence, we exploit extensively time series and Fourier transforms. We discuss in detail quantitatively the question whether all the DSs found for the cubic complex Ginzburg-Landau equation with nonlinear gradient terms are generic, meaning whether they are stable against structural perturbations, for example, to the additions of a small quintic perturbation as it arises naturally in an envelope equation framework. Finally, we examine to what extent it is possible to have different types of DSs for fixed parameter values in the equation by just varying the initial conditions, for example, by using narrow and high vs broad and low amplitudes. These results indicate an overlapping multi-basin structure in parameter space.

RESUMO

PURPOSE: Clobazam (CLB) has an important antiepileptic effect and is less expensive than the new antiepileptic drugs (AEDs), but still has not been considered as first-line drug in the treatment of epilepsy. We evaluated the efficacy of CLB as add-on therapy in patients with refractory partial epilepsy. METHODS: This was an open, retrospective study, conducted at the epilepsy clinic of our university hospital. All patients had chronic epilepsy and were being evaluated for epilepsy surgery. CLB was introduced as add-on therapy (starting with 10 mg/ day) in patients with previous failure of at least two AEDs. Information was obtained from clinical notes and follow-up visits. RESULTS: We evaluated 97 patients, 37 men and 60 women. Ages ranged from 15 to 70 years (mean, 35.8 years). Etiology of epilepsy was hippocampal atrophy in 67 (69%), cortical dysgenesis in nine (9.3%), and other etiologies in nine (9.3%). In 12 (12.3%) patients, the etiology of epilepsy was not identified despite clinical and neurologic investigation. Patients used CLB for a period ranging from 1 month to 7 years and 9 months (mean, 16.7 months) with doses ranging from 10 to 60 mg/day (mean, 29.7 mg/day). Seven (7.2%) patients were seizure free, 48 (49.4%) had > or =50% of improvement in seizure control, 39 (40.2%) had <50% of improvement in seizure control, and in three (3.1%), no data were available. CONCLUSIONS: We conclude that CLB may have efficacy equivalent to that of the new AEDs when used as add-on therapy in patients with refractory epilepsy. CLB should be considered an economic alternative in the treatment of patients with refractory epilepsy.

Assuntos

Ansiolíticos/uso terapêutico , Anticonvulsivantes/uso terapêutico , Benzodiazepinas , Epilepsias Parciais/tratamento farmacológico , Adolescente , Adulto , Idoso , Ansiolíticos/administração & dosagem , Anticonvulsivantes/administração & dosagem , Clobazam , Esquema de Medicação , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento

RESUMO

OBJECTIVE: To investigate the clinical and genetic characteristics of familial partial epilepsies. METHOD: Family history of seizures was questioned in all patients followed in our epilepsy clinics, from October 1997 to December 1998. Those with positive family history were further investigated and detailed pedigrees were obtained. All possibly affected individuals available underwent clinical evaluation. Seizures and epilepsy syndromes were classified according to the ILAE recommendations. Whenever possible, EEG and MRI were performed. RESULTS: Positive family history was identified in 32 unrelated patients. A total of 213 possibly affected individuals were identified, 161 of whom have been evaluated. The number of affected subjects per family ranged from two to 23. Temporal lobe epilepsy (TLE) was identified in 22 families (68%), frontal lobe epilepsy in one family (3%), partial epilepsy with centrotemporal spikes in five families (15%), and other benign partial epilepsies of childhood in four families (12%). Most of the affected individuals in the TLE families (69%) had clinical and/or EEG characteristics of typical TLE. However, the severity of epilepsy was variable, with 76% of patients with spontaneous seizure remission or good control with medication and 24% with refractory seizures, including 7 patients that underwent surgical treatment. In the other 10 families, we identified 39 possibly affected subjects, 23 of whom were evaluated. All had good seizure control (with or without medication) except for one patient with frontal lobe epilepsy. Pedigree analysis suggested autosomal dominant inheritance with incomplete penetrance in all families. CONCLUSION: Family history of seizures is frequent among patients with partial epilepsies. The majority of our families had TLE and its expression was not different from that observed in sporadic cases. The identification of genes involved in partial epilepsies may be usefull in classification of syndromes, to stablish prognosis and optimal treatment.

Assuntos

Epilepsias Parciais/genética , Adolescente , Adulto , Atrofia , Brasil/epidemiologia , Eletroencefalografia , Epilepsias Parciais/epidemiologia , Epilepsias Parciais/fisiopatologia , Epilepsia do Lobo Temporal/epidemiologia , Epilepsia do Lobo Temporal/genética , Epilepsia do Lobo Temporal/fisiopatologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade

RESUMO

A survey was carried out in 2 drug use treatment centres (TCs) in Rio de Janeiro, Brazil, to assess risk behaviours, HIV infection and other sexually transmitted infections/blood-borne infections (STIs/BBIs). Two hundred and twenty-five drug users (195 males and 30 females) were interviewed and clinically examined, and their blood and urine were tested for STIs/BBIs. Prevalences (%) for these infections were as follows--HIV: 0.9, hepatitis B virus (HBV): 14.7, hepatitis C virus (HCV): 5.8, syphilis: 5.3, gonorrhoea/chlamydia (CT/NG): 4.7. In bivariate analyses CT/NG infection was associated with younger age (P=0.003); current genitourinary symptoms (odds ratio [OR]=6.2) and a mainly illegal source of income (OR=9.1). Hepatitis C infection was associated with a history of ever having injected any drug (OR=19.6), and with each one of the injected drugs. After multiple logistic regression, lower educational level (adjusted odds ratio [AOR]=3.70) and 'ever having injected drugs' (AOR=3.69) remained as independent risk factors for hepatitis B infection. In conclusion, TCs must implement programmes directed towards the prevention of STIs/BBIs.

Assuntos

Infecções por HIV/epidemiologia , Assunção de Riscos , Comportamento Sexual , Infecções Sexualmente Transmissíveis/epidemiologia , Centros de Tratamento de Abuso de Substâncias/estatística & dados numéricos , Adolescente , Adulto , Fatores Etários , Brasil/epidemiologia , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Prevalência , Infecções Sexualmente Transmissíveis/sangue , Infecções Sexualmente Transmissíveis/urina

RESUMO

The Brazilian Network for HIV Isolation and Characterization was established for the surveillance of HIV variability in Brazil. Here, we report characterization of HIV strains and virus-specific immune responses from 35 clinical samples collected from three potential HIV vaccine sites. Three genetic subtypes of HIV-1 were identified by heteroduplex mobility assay (HMA) B (in 82.9% of the samples), F (14.3%), and C (2.9%). Phylogenetic analysis based on the C2V3/env DNA sequence from all 25 specimens examined was 100% concordant with HMA results. Four variants of subtype B with different tetrapeptides at the tip of the V3 loop were found: the GPGR motif (North American), GWGR motif (Brazilian B"), and two minor variants, GFGR and GPGS, as previously detected. No significant association was found between HIV-1 subtypes and the mode of transmission or biologic properties of HIV-1 isolates (derived from 88.6% of the specimens). Only 5 of 16 isolates studied were neutralized by the autologous sera. Consistent with previous results, no relation between viral subtype and peptide enzyme-linked immunosorbent assay (ELISA) seroreactivity or neutralization was evident. This study also demonstrated the effectiveness of the collaborative approach followed by Brazilian scientists when addressing a complex subject such as HIV variability.

Assuntos

Vacinas contra a AIDS , Infecções por HIV/epidemiologia , HIV-1/classificação , Adolescente , Adulto , Sequência de Aminoácidos , Brasil/epidemiologia , Feminino , Proteína gp120 do Envelope de HIV/análise , Infecções por HIV/virologia , HIV-1/genética , HIV-1/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Fragmentos de Peptídeos/análise , Filogenia , Fatores de Risco , Análise de Sequência

RESUMO

In order to test the predictive value of immune complex-dissociated p24 antigenaemia (ICD-p24Ag), beta 2 microglobulin (beta 2-M), and neopterin as markers of disease progression, 53 HIV-1 infected children (mean age 68 months) and nine HIV-negative controls (mean age 65 months) were studied prospectively for 9 months. Five were classified in category E (CDC-1994) and seroreverted during the study, 14 in category A, nine in category B, and 25 in category C (CDC-1994). Blood samples were taken at medium intervals of 61 days and tested for ICD-p24Ag, beta 2 microglobulin, and neopterin. The results were correlated with clinical outcome and CD4-lymphocyte counts. All three groups (A, B, C) of symptomatic children had similar positivity in an ICD-p24Ag test (48.1, 58.8, and 51.0 per cent, respectively), and all in group E had negative p24 antigenaemia. beta 2 microglobulin and neopterin tests showed no correlation with clinical stages of HIV-1 infection. There was no significant correlation between these three tests with age-matched CD4 lymphocyte counts (p > 0.05). In contrast, the CD4 lymphocyte count correlated well with disease stages. These data suggest that the markers evaluated in the present study do not correlate well with clinical findings or with CD4 lymphocyte counts. Of all the markers tested, CD4 count was the best to predict prognosis of HIV disease in this cohort.

Assuntos

Biomarcadores/sangue , Infecções por HIV/sangue , HIV-1 , Brasil , Contagem de Linfócito CD4 , Criança , Progressão da Doença , Proteína do Núcleo p24 do HIV/sangue , Infecções por HIV/fisiopatologia , Humanos , Neopterina/sangue , Microglobulina beta-2/sangue

RESUMO

OBJECTIVE: Constant antigenic stimulation of the large immune cell population contained within gut-associated lymphoid tissue during HIV infection may contribute to patients' total viral load. The aim of this investigation was to evaluate the effect of a mucosal antigenic challenge on HIV replication. DESIGN: Prospective clinical study. METHODS: Twelve HIV-1-infected men (mean age, 42.3 years) from the Casa de Apoio Santo Antonio, Rio de Janeiro, Brazil, were immunized with combined whole cell-toxin B subunit oral cholera vaccine. Blood was collected on days 0, 2, 4, 6, 10 and 15 after immunization and plasma was tested for cholera toxin-specific antibody response (IgG and IgA), beta2-microglobulin, and plasma viral load. CD4 lymphocyte counts were performed within 1 week before immunization. Five HIV-infected non-immunized individuals were studied as controls. RESULTS: There were no adverse effects following immunization and no deterioration in clinical outcome during 3 months of follow-up. A transient increase in viral load that ranged from twofold to 60-fold was observed in all cases and was statistically significant on days 2, 6 and 10 (P = 0.017, P = 0.025, P = 0.021, respectively). There was no correlation with CD4 cell counts. None of the non-immunized subjects demonstrated the pattern of viraemia observed after immunization (P > 0.10 on all days). CONCLUSIONS: Our data indicate that mucosal immunization with oral cholera vaccine induces a transient increase in HIV viraemia, regardless of clinical stage of infection and CD4 cell counts. These findings suggest that mucosal stimulation of HIV-infected patients enhances HIV replication.

Assuntos

Vacinas contra Cólera/imunologia , Infecções por HIV/imunologia , HIV-1/fisiologia , Carga Viral , Administração Oral , Adulto , Antitoxinas/sangue , Contagem de Linfócito CD4 , Toxina da Cólera/imunologia , Vacinas contra Cólera/administração & dosagem , Infecções por HIV/virologia , Humanos , Imunidade nas Mucosas , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Replicação Viral , Microglobulina beta-2/análise

Assuntos

DNA Viral/genética , Infecções por HIV/epidemiologia , Infecções por HIV/genética , Polimorfismo de Fragmento de Restrição , Brasil/epidemiologia , Feminino , Humanos , Masculino

RESUMO

HIV-1-positive individuals were recruited from January 1993 to December 1996 from several cohorts receiving follow-up in the city of Rio de Janeiro, Brazil, to evaluate HIV-1 genetic variability and the potential association with modes of transmission. HIV-1 subtyping was carried out using the heteroduplex mobility assay (HMA), and those samples corresponding to the typical Brazilian subtype B variant were further identified based on the Fok I restriction fragment length polymorphism (RFLP). DNA sequencing was performed to evaluate one case of subtype D infection. From the 131 HIV-1-positive individuals analyzed, 106 (80.9%) could be identified as infected by subtype B and 20 (15.3%) by subtype F. One of the samples (0.8%) was classified as subtype D. DNA samples from 4 patients (3.0%) did not yield polymerase chain reaction (PCR)-amplified products to be typed. Based on the Fok I RFLP, 39 of the 106 subtype B samples (37%) were identified as corresponding to the typical Brazilian subtype B variant containing the GWGR motif at the tip of the V3 loop. No statistically significant association could be detected between HIV-I subtypes and modes of transmission, exposure categories, or gender. This is the first reported case of HIV-1 subtype D infection in Brazil.

Assuntos

Infecções por HIV/epidemiologia , HIV-1/classificação , Sequência de Aminoácidos , Brasil/epidemiologia , Estudos de Coortes , Sequência Consenso , DNA Viral/química , Feminino , Produtos do Gene env/química , Produtos do Gene env/genética , Variação Genética , Infecções por HIV/transmissão , Infecções por HIV/virologia , HIV-1/genética , Humanos , Masculino , Epidemiologia Molecular , Dados de Sequência Molecular , Ácidos Nucleicos Heteroduplexes , Filogenia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Prevalência , Alinhamento de Sequência , Distribuição por Sexo , População Urbana

Assuntos

HIV , Antígenos HIV , HIV-1 , Epidemiologia Molecular , Polimorfismo Genético , Brasil , Síndrome da Imunodeficiência Adquirida/epidemiologia

Assuntos

Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Fármacos Anti-HIV/uso terapêutico , Fármacos Anti-HIV/administração & dosagem , Brasil , Quimioterapia Combinada , Pessoas Mal Alojadas , Humanos , Estudos Prospectivos , Sobreviventes

Assuntos

Humanos , Sítios de Ligação , HIV-1 , Polimorfismo Genético , Vacinas contra a AIDS , Sequência de Aminoácidos , Sequência Consenso , Epitopos , Variação Genética , HIV-1 , Peptídeos/genética , Peptídeos/imunologia

Assuntos

Síndrome da Imunodeficiência Adquirida/prevenção & controle , HIV-1/isolamento & purificação , Vacinas contra a AIDS , Adolescente , Adulto , Variação Antigênica , Brasil , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos , Feminino , Variação Genética , HIV-1/genética , HIV-1/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto

Assuntos

Sítios de Ligação , HIV-1/genética , Polimorfismo Genético , Vacinas contra a AIDS , Sequência de Aminoácidos , Sequência Consenso , Epitopos , Variação Genética , HIV-1/imunologia , HIV-1/isolamento & purificação , Humanos , Peptídeos/genética , Peptídeos/imunologia

RESUMO

PURPOSE: To evaluate the early physical conditioning (PC) effect [initiated 15 days after the myocardial revascularization surgery (MRS)] in the functional capacity. METHODS: Twenty-two male patients (mean-age of 52y-o), divided in two groups (A and B, 11 patients each), were studied. Group A started PC 3 months after MRS (phase III), with a training intensity of about 70% of the maximum heart rate reserve, during three months, three sessions per week with one hour duration. Group B started PC 15 days after the MRS (fase II), with a training intensity up to five metabolic unities, three times a week, 1 hour and 15 duration. The post-MRS period of three months was designated as the time I (beginning of fase III) and six months as time 2. Stress test, Kraus-Weber flexibility test, coxo-femural flexibility test (flexion, elevation and abduction) and scapule-umeral flexibility test (flexion, extension and abduction) were applied. RESULTS: The maximum oxygen uptake and the total work increased significantly from time 1 to time 2 in both groups, but there was no significant difference between the two groups, either in time 1 or 2. Flexibility in the Kraus-Weber test and in the scapule-umeral flexibility test when in flexion, were significantly greater in group B than A, in both times (1 and 2). Other flexibility variables studied show no significant difference, neither between the studied groups nor in the times 1 and 2 of evaluation. CONCLUSION: Early PC after MRS increased the value of two variables that measure flexibility. However, it has not increased other flexibilities variables and the aerobic capacity.

Assuntos

Terapia por Exercício/métodos , Capacidade Residual Funcional , Revascularização Miocárdica/reabilitação , Consumo de Oxigênio , Análise de Variância , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Fatores de Tempo , Trabalho Respiratório

RESUMO

Twenty-two women with uterine carcinoma with morphological alterations postradiation treatment suggestive of Chlamydia trachomatis infection were analyzed by direct immunofluorescence. The diagnosis was confirmed in 12 (54.4%) cases. Discussions of the presence of Chlamydia in irradiated cells were not found in the literature. This finding may signify a posttherapeutic morbidity or a preradiation infection.

Assuntos

Adenocarcinoma/radioterapia , Carcinoma de Células Escamosas/radioterapia , Infecções por Chlamydia/microbiologia , Chlamydia trachomatis/isolamento & purificação , Neoplasias do Colo do Útero/radioterapia , Adenocarcinoma/microbiologia , Adenocarcinoma/patologia , Adulto , Idoso , Carcinoma de Células Escamosas/microbiologia , Carcinoma de Células Escamosas/patologia , Infecções por Chlamydia/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias do Colo do Útero/microbiologia , Neoplasias do Colo do Útero/patologia

RESUMO

Some authors recently suggested the role of Chlamydia trachomatis as a potentiating agent of female genital tract neoplasias. Cervicovaginal smears of women with uterine carcinoma treated with radiotherapy are analyzed in the present work. A series of such smears showed morphological changes suggestive of Chlamydia infection with the Papanicolaou stain. Confirmation of the presence of such agent was done using an avidin-biotin-peroxidase technique. A higher prevalence of Chlamydia in the group of patients with carcinoma of the uterus treated with irradiation than in the population without ionizing treatment was verified. The presence of cells with radiotherapic changes infected by Chlamydia is a new finding in cytology.

Assuntos

Infecções por Chlamydia/diagnóstico , Chlamydia trachomatis/isolamento & purificação , Teste de Papanicolaou , Esfregaço Vaginal , Colo do Útero/efeitos da radiação , Feminino , Humanos , Técnicas Imunoenzimáticas , Imuno-Histoquímica , Neoplasias Uterinas/radioterapia

Assuntos

Doadores de Sangue , Anticorpos Anti-HIV/análise , Brasil , Doença de Chagas/diagnóstico , Humanos , Pobreza , Sífilis/diagnóstico

RESUMO

PIP: The prevalence of HIV antibodies, as well as evidence of hepatitis B, syphilis, and Chagas' disease, was tested in 87 male and 13 female clients of a church-funded medical clinic in Rio de Janeiro who often donated blood to commercial blood banks. 5 individuals were seropositive for HIV, 2 homosexuals, 1 bisexual, and 2 heterosexuals. 21 had evidence of hepatitis B, including 2 with HBsag antibodies. 13 tested positive for syphilis, and 5 were positive for T. cruzi (Chagas' disease). The high incidence of positive tests for hepatitis B and Chagas' disease was possibly due to donation by plasmapheresis, which has been suspected to cause outbreaks of non-A, non-B hepatitis and malaria in this area. The practice of selling contaminated blood to unsuspecting recipients should be prevented no matter how high the cost.^ieng

Assuntos

Doadores de Sangue , Anticorpos Anti-HIV/análise , Brasil , Doença de Chagas/diagnóstico , Soropositividade para HIV/diagnóstico , Hepatite B/diagnóstico , Humanos , Masculino , Fatores Socioeconômicos , Sífilis/diagnóstico