RESUMO
In the last decade, the vision systems have improved their capabilities to capture 3D images in bad weather scenarios. Currently, there exist several techniques for image acquisition in foggy or rainy scenarios that use infrared (IR) sensors. Due to the reduced light scattering at the IR spectra it is possible to discriminate the objects in a scene compared with the images obtained in the visible spectrum. Therefore, in this work, we proposed 3D image generation in foggy conditions using the single-pixel imaging (SPI) active illumination approach in combination with the Time-of-Flight technique (ToF) at 1550 nm wavelength. For the generation of 3D images, we make use of space-filling projection with compressed sensing (CS-SRCNN) and depth information based on ToF. To evaluate the performance, the vision system included a designed test chamber to simulate different fog and background illumination environments and calculate the parameters related to image quality.
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Introducción: los principales factores de riesgo descritos para contraer la infección por el virus de la hepatitis C (VHC) son antecedentes de transfusión sanguínea y uso de droga endovenosa; el riesgo por transmisión sexual es controversial. Existen pocos estudios de VHC en trabajadoras sexuales (TS) en el Perú, encontrando bajas prevalencias de VHC (0-1%). El presente estudio se ha realizado en Iquitos, una ciudad en la selva peruana, en donde existe gran comercio sexual y la prevalencia de HIV/SIDA y otras Infecciones de Transmisión Sexual (ITS) es alta. Objetivo: determinar la seroprevalencia de anticuerpos contra el VHC en TS de la ciudad de Iquitos atendidas en un Centro Especializado de Referencia de Infecciones de transmisión sexual (CERITSS) e identificar los factores de riesgo asociados a esta. Material y métodos: es un estudio de corte transversal en TS quienes acudieron a su control periódico al CERITSS San Juan entre mayo 2003 a enero 2004. Una encuesta clínica-epidemiológica fue utilizada para determinar la frecuencia de factores de riesgo para adquirir la infección por VHC. Para determinar la presencia de anticuerpos contra el VHC, se utilizó la prueba de enzima inmunoensayo (EIA); todos los resultados positivos fueron confirmados con la prueba inmunoblot recombinante (RIBA). Resultados: cuatro de las 200 TS enroladas en el estudio fueron positivos para la prueba EIA, todas ellas tuvieron resultados positivos de RIBA (prevalencia de 2%, IC95% 0,06-3,94%). Estas 4 TS reportaron ser naturales de Iquitos, tener mas de 5 años de trabajo sexual, reportaron un bajo uso de condón (<50%). Tres de ellas reportaron haber tenido mas de 9 parejas/ día, realizar trabajo sexual bajo efecto del alcohol y tener sexo anal frecuentemente. Ninguna refirió transfusiones sanguíneas, antecedente de tatuajes o uso de drogas endovenosas. Solo una de las 4 VHC positivas tuvo serología positiva para sífilis co-existentemente y ninguna para VIH. Una de las 200 TS enroladas tuvo infección por VIH. Conclusiones: la seroprevalencia de anticuerpos contra el VHC en TS es mayor que la reportada en poblaciones similares en otras ciudades del Perú. Esta población se caracterizó por tener una conducta sexual de alto riesgo y no tener antecedentes de transfusión sanguínea ni consumo de droga endovenosa.
Introducction: the principal described risk factors to contract the hepatitis C virus (HCV) are blood transfusion antecedents and intravenous drug use; sexual transmission risk is controversial. In Peru there exist few studies whose female sex worker (FSW) HCV prevalence oscillates between 0-1%. The present study is based in Iquitos, a Peruvian jungle city with high sexual commerce and HIV/AIDS prevalence. Objetive: determine the HCV serological prevalence in Iquitos FSWs attending the STI/ HIV specialist center (CERITSS) and identify associated risk factors. Material and methods: cross-sectional study in FSWs who attended periodic San Juan CERITSS examinations from May 2003 to January 2004. Epidemical questionnaires where used to evaluate the risk factors. To determine HCV antibodies presence, the immunoassay enzyme (EIA) positive results were confirmed by the recombinant immunoblot assay (RIBA) test. Results: 4/200 FSWs enrolled in the study were EIA test positive; all had confirmed positive RIBA results, representing 2%(95%IC 0,06%-3,94%) prevalence. the 4 FSWs referred to be were born in Iquitos, to having been a sex worker for five years and stated condom use was <50%. Three to having had 9 sexual clients daily; to heavy alcohol consumption and to frequent anal sex . None declared intravenous drug use; having had tattoos and blood transfusions. Only one of 4 HCV positives had syphilis serology and none had HIV infections. 1/200 was diagnosed with HIV. Conclusion: the antibody against HCV seroprevalence in Iquitos FSWs is greater than reported in similar populations or the general population of other Peruvian cities. This population was characterized by having high risk sexual behavior and no blood transfusion antecedent nor intravenous drug user.
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We present data on the molecular characterisation of strains of Trypanosoma rangeli isolated from naturally infected Rhodnius ecuadoriensis in Peru, from Rhodnius colombiensis, Rhodnius pallescens and Rhodnius prolixus in Colombia, and from Rhodnius pallescens in Panama. Strain characterisation involved a duplex PCR with S35/S36/KP1L primers. Mini-exon gene analysis was also carried out using TrINT-1/TrINT-2 oligonucleotides. kDNA and mini-exon amplification indicated dimorphism within both DNA sequences: (i) KP1, KP2 and KP3 or (ii) KP2 and KP3 products for kDNA, and 380 bp or 340 bp products for the mini-exon. All T. rangeli strains isolated from R. prolixus presented KP1, KP2 and KP3 products with the 340 bp mini-exon product. By contrast, all T. rangeli strains isolated from R. ecuadoriensis, R. pallescens and R. colombiensis, presented profiles with KP2 and KP3 kDNA products and the 380 bp mini-exon product. Combined with other studies, these results provide evidence of co-evolution of T. rangeli strains associated with different Rhodnius species groups east and west of the Andean mountains.
Assuntos
Evolução Molecular , Rhodnius/parasitologia , Trypanosoma/genética , Animais , Colômbia , DNA Intergênico/genética , DNA de Cinetoplasto/genética , DNA de Protozoário/genética , Éxons/genética , Interações Hospedeiro-Parasita/genética , Panamá , Peru , Filogenia , Trypanosoma/classificaçãoRESUMO
PURPOSE: Infantile spasms (ISs) are age-dependant epileptic seizures, which may be flexor, extensor, lightning or nods, or mixed. The aim of this study was the analysis of genetic factors within the human leukocyte antigen (HLA) complex associated with ISs. METHODS: Sixty-five patients diagnosed according to the established international criteria were compared with 229 healthy individuals; all of them were Mexican Mestizos. Five families were also analyzed (seven affected and five healthy sibs); HLA class I and class II antigens were typed using the standard microlymphocytotoxicity methods. RESULTS: The findings showed female gender preference (2:1). Two thirds were symptomatic, and prevalent seizures were of mixed type (67%). A strong association with HLA-DR17 was detected in the IS group (pc < 0.01; OR = 3.6; EF = 0.20). DR17 was also found increased in the symptomatic patients (p = 0.009; OR = 3.16) and in those with other types of seizures (p = 0.001; OR = 2.0). Conversely, HLA-DQ6 was significantly decreased (pc < 0.002; PF = 0.37) in the total and in the symptomatic groups (p < 0.01). Haplotype linkage was not confirmed in the families; however, those with more than one affected sib shared at least one haplotype. CONCLUSIONS: These findings suggest the contribution of DR locus to the susceptibility and the participation of DQ region in the resistance to IS. Severity seems also to be influenced by HLA-DR17, and therefore class II typing may be a helpful tool for disease prognosis.
Assuntos
Etnicidade/genética , Genes MHC da Classe II/genética , Espasmos Infantis/genética , Adulto , Idade de Início , Comorbidade , Família , Feminino , Genes MHC Classe I/genética , Ligação Genética , Antígenos HLA-DQ/genética , Antígenos HLA-DR/genética , Subtipos Sorológicos de HLA-DR , Haplótipos , Humanos , Lactente , Masculino , México/epidemiologia , Linhagem , Prognóstico , População Rural , Fatores Sexuais , Espasmos Infantis/diagnóstico , Espasmos Infantis/epidemiologiaRESUMO
Trypanosoma rangeli can infect humans as well as the same domestic and wild animals and triatomine vectors infected by Trypanosoma cruzi in Central and South America. This overlapping distribution complicates the epidemiology of American trypanosomiasis due to the cross-reactivity between T. rangeli and T. cruzi antigens and the presence of conserved DNA sequences in these parasites. We have isolated a T. rangeli-specific DNA repetitive element which is represented in approximately 103 copies per parasite genome and is distributed in several chromosomal bands. The 542-bp nucleotide sequence of this element, named P542, was determined and a PCR assay was standardized for its amplification. The sensitivity of the assay is high, allowing the detection of one tenth of the DNA content of a single parasite. The presence of the P542 element was confirmed in 11 T. rangeli isolates from mammalian hosts and insect vectors originating from several countries in Latin America. Negative amplification was observed with different T. cruzi strains and other trypanosomatids. The potential field application of the P542 PCR assay was investigated in simulated samples containing T. rangeli and/or T. cruzi and intestinal tract and feces of Rhodnius prolixus. Epidemiological studies were conducted in DNA preparations obtained from the digestive tracts of 12 Rhodnius colombiensis insects collected in a sylvatic area in Colombia. Positive amplification of the P542 element was obtained in 9/12 insects. We have also compared in the same samples the diagnostic performance of two PCR assays for the amplification of the variable domain of minicircle kinetoplast DNA (kDNA) and of the large subunit (LSU) of the ribosomal RNA gene of T. cruzi and T. rangeli. Data indicate that the kDNA PCR assay does not allow diagnosis of mixed infections in most insects. On the other hand, the PCR assay of the LSU RNA gene showed lower sensitivity in the detection of T. rangeli than the PCR assay of the P542 element. It is predicted that the use of sensitive detection techniques will indicate that the actual distribution of T. rangeli in America is wider than presumed.
Assuntos
Doença de Chagas/epidemiologia , DNA de Protozoário/química , Sequências Repetitivas de Ácido Nucleico , Trypanosoma/isolamento & purificação , Animais , Sequência de Bases , Southern Blotting , Doença de Chagas/diagnóstico , Doença de Chagas/parasitologia , Colômbia/epidemiologia , Enzimas de Restrição do DNA , DNA de Cinetoplasto/química , DNA de Cinetoplasto/isolamento & purificação , DNA de Protozoário/isolamento & purificação , Diagnóstico Diferencial , Eletroforese em Gel de Ágar , Eletroforese em Gel de Campo Pulsado , Humanos , Insetos Vetores/parasitologia , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , RNA Ribossômico/genética , Rhodnius/parasitologia , Sensibilidade e Especificidade , Análise de Sequência de DNA , Especificidade da Espécie , Trypanosoma/genéticaRESUMO
The pathogenicity of Phylloporia chrysita (Berk.) Ryv. on Erythrochiton gymnanthus K. (Rutaceae) was studied in Carara Biological Reserve, seasonal Pacific of Costa Rica. Growth rate and distribution of basidiocarps were determined on health and diseased plants. P. chrysita caused 52% growth reduction on diseased plants. Fungal hyphae were observed on epidermis, parenchyma and vascular tissue, where they caused cellular breakdown.
Assuntos
Basidiomycota/patogenicidade , Doenças das Plantas/microbiologia , Basidiomycota/classificaçãoRESUMO
To examine the effects of avocado on plasma lipid concentrations a two-diet trial involving 8 phenotype IV and 8 phenotype II dyslipidemia patients was carried out. A diet rich in monounsaturated fatty acids (DRCA) using the avocado as their major source (30% of the total calories were consumed as fat, 75% of the total fat from the avocado), with restriction of saturated fat and less of 300 mg of cholesterol per day was evaluated. Patients also were in a low-saturated fat diet without avocado (DRSA). The three daily meals were eaten at our clinical unit. Diets were four weeks in duration and they were assigned in a crossover design. In phenotype II both DRCA and DRSA significantly reduced total cholesterol and LDL-cholesterol levels. On phenotype IV DRCA produced a mild reduction on triglyceride levels while DRSA increased them. On HDL-cholesterol concentrations DRCA produced a significant increase in both phenotypes while DRSA did it only in phenotype IV. Avocado is an excellent source of monounsaturated fatty acids in diets designed to treat hypercholesterolemia with some advantages over low-fat diets with a greater amount of carbohydrates.
Assuntos
Ácidos Graxos Monoinsaturados , Hiperlipoproteinemia Tipo II/dietoterapia , Hiperlipoproteinemia Tipo IV/dietoterapia , Lipídeos/sangue , Verduras , Idoso , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Gorduras Insaturadas na Dieta , Feminino , Humanos , Hiperlipoproteinemia Tipo II/sangue , Hiperlipoproteinemia Tipo IV/sangue , Masculino , Pessoa de Meia-IdadeRESUMO
The etiology of Bell's palsy (BP) is still unknown, but infectious, immunological and genetic factors have been suggested to play a role in the pathogenesis of the disease. We analyzed blood samples of 92 Mexican Mestizo patients diagnosed as having BP according to established international criteria, and the results were compared to a group of apparently healthy controls of the same ethnic origin. HLA class I (A, B, C) and Class II (DR, DQ) products of the major histocompatibility complex (MHC), and the percentages of CD3, CD4 and CD8 T-cell subsets were investigated. The number of family antecedents was surprisingly high (46%), supporting a genetic basis. There was a slight increase of DRw13, suggesting a possible susceptibility class II-linked gene. A significant decrease of DR4 (pc = 0.001) was detected, which may indicate the existence of a resistance DR-linked gene. Thus, a non DR4 carrier may be in high risk of expressing BP. In the acute phase of the disease, the T-cell subsets showed a decrease in CD3 and CD4 cells when compared to controls. CD8 cells were increased in the same stage. A transient T-cell imbalance was thus observed which recovered in the convalescent phase. None of the patients with CD4 lower than 40% were DR4, suggesting that the DR-linked resistance gene may predispose to the T-cell defect.
Assuntos
Paralisia Facial/genética , Genes MHC da Classe II/genética , Antígenos HLA-DR/genética , Subpopulações de Linfócitos T/imunologia , Adulto , Paralisia Facial/imunologia , Feminino , Marcadores Genéticos , Humanos , Masculino , México/etnologiaRESUMO
The lethality of d-amphetamine was studied in isolated and aggregated mice with and without previous habituation to the physical or to the physical and social environment of chronically aggregated social condition under which the toxic effects of d-amphetamine were tested. In animals without previous habituation to such environments, d-amphetamine's toxicity was greatly enhanced by social aggregation, as reported by several authors in the literature. It was found that mortality in the dose range from 5 to 90 mg/kg is mainly determined by the stimulation due to aggregation. Above 90 mg/kg, the mortalities in single and aggregated mice vary in parallel. Up from this dose, lethality is independent of the external stimulation. Previous experience with house sharing in aggregated conditions reduces aggregation mortality in proportion to the duration of the previous house sharing period.