Vitamin D Intake and Cardiometabolic: Risk Factors in Adolescents

Background: A growing body of research suggests that vitamin D might play an important role in overall health. No data exist on vitamin D intake for the Azorean adolescent population. The purpose of this study was to assess vitamin D intake and investigate a possible association between vitamin D intake and cardiometabolic risk factors in Azorean adolescents. Methods: A cross-sectional school-based study was conducted on 496 adolescents (288 girls) aged 15–18 years from the Azorean Islands, Portugal. Anthropometric measurements (waist circumference and height), blood pressure (systolic), and plasma biomarkers [fasting glucose, insulin, total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and triglycerides (TGs)] were measured to assess metabolic risk. Homeostasis model assessment (HOMA), TC-to-HDL-C ratio, and waist-to-height ratio were calculated. For each of these variables, a Z-score was computed by age and sex. A metabolic risk score was constructed by summing the Zscores of all individual risk factors. High risk was considered when the individual had ‡ 1 standard deviation(SD) of this score. Vitamin D intake was assessed with a semiquantitative food frequency questionnaire. Participants were classified into quartiles of vitamin D intake. Logistic regression was used to determine odds ratios for high cardiometabolic risk scores after adjusting for total energy intake, pubertal stage, fat mass percentage, and cardiorespiratory fitness. Results: Mean (SD) vitamin D intake was 5.8 (6.5) mg/day, and 9.1% of Azorean adolescents achieved the estimated average requirement of vitamin D (10 mg/day or 400 IU). Logistic regression showed that the odds ratio for a high cardiometabolic risk score was 3.35 [95% confidence interval (CI) 1.28–8.75] for adolescents in the lowest vitamin D intake quartile in comparison with those in the highest vitamin D intake quartile, even after adjustment for confounders. Conclusion: A lower level of vitamin D intake was associated with worse metabolic profile among Azorean adolescents.

Establishing a high titer transient gene expression process in conditioned media for CHO-DG44 cells

Dissertação para obtenção do Grau de Mestre em Biotecnologia

Embolização das artérias prostáticas no tratamento da hiperplasia benigna da próstata : estudo anátomo-clínico

Resumo: A hiperplasia benigna da próstata (HBP) tem elevada prevalência nos homens entre os 50 e 79 anos de idade, sendo ubiquitária com o envelhecimento. Devido à significativa morbi-mortalidade associada aos tratamentos médicos e cirúrgicos currentemente disponíveis, são necessárias novas tecnologias para melhorar os resultados e minimizar o desconforto dos doentes. Recentemente, estudos preliminares de experimentação animal e em 3 doentes tratados, sugeriram a embolização arterial prostática selectiva (EAPS) como hipótese terapêutica para a HBP. Decidimos investigar se a EAPS poderia ser um procedimento bem sucedido no tratamento da HBP gravemente sintomática. Para tal realizámos um estudo anátomo-radiológico e clínico em 63 doentes com recurso a uma terapêutica inovadora minimamente invasiva guiada pela imagem. Avaliámos 126 hemipélvis com recurso a Angio-RM, Angio-TC e Angiografia Digital de Subtracção, com o intuito de definir os padrões básicos de bifurcação das artérias ilíacas internas até agora apenas descritos em estudos cadavéricos. Estudámos ainda o suprimento vascular arterial prostático, identificando: 1 as artérias prostáticas; 2 origem e direcção; 3 os ramos intra-prostáticos; 4 anastomoses com outras artérias. Em relação aos resultados anatómicos, identificámos 181 artérias prostáticas, já que em 43.7% das hemipélvis existiam dois pedículos arteriais prostáticos com origens independentes. A origem mais frequente foi a artéria pudenda interna (39.7%), seguida do tronco comum glúteo-pudendo (21%) e da artéria vesical superior (18.2%). Origens menos frequentes foram a artéria obturadora (12.1%), as artérias glúteas inferior (3.9%)ou superior (1.7%), ramos rectais provenientes da artéria mesentérica inferior (1.7%) e a artéria pudenda acessória (1.7%). Identificaram-se anastomoses com as artérias adjacentes em 57.9% dos casos: com a terminação da artéria pudenda interna (41.6%),artérias prostáticas contra-laterais (18.2%) e homo-laterais (11.7%), com ramos rectais (15.6%) e com artérias vesicais (12.9%). Em relação ao estudo clínico tratámos 63 doentes (idades compreendidas entre 52 - 82 anos, média 69.5 anos) com HBP gravemente sintomática refractária à terapêutica médica há mais de 6 meses. Foi possível avaliação após o tratamento em 37 doentes: média de seguimento de 4.7 meses (variando entre 1 e 12 meses). A EAPS unilateral foi possível em todos os doentes, com embolização bilateral em 73% dos casos. A embolização bilateral não foi possível em 27% dos casos devido a tortuosidade, alterações ateroescleróticas e pequeno calibre das artérias ilíacas e/ou prostáticas. Em média houve uma melhoria do International Prostate Symptom Score (IPSS) de 10.8 pontos, da QoL de 1.5 pontos e do Internationl Index of Erectile Function (IIEF) de 2.1 pontos. Houve uma redução média do PSA de 30% (2.4 ng/mL), um aumento do pico de fluxo urinário (Qmax) de 3.1 - 3.85 mL/s e uma redução média do volume prostático de 21% (18.5 mL). Registou-se uma complicação major: pequena área de isquémia da parede vesical tratada cirurgicamente. Em 75% dos doentes tratados obteve-se sucesso clínico com franca melhoria dos sintomas, enquanto 25% dos doentes foram considerados insucesso clínico por se ter registado uma fraca ou ausente melhoria sintomática após a embolização. Os restantes doentes tratados estão sob controlo evolutivo, pararam toda a medicação prostática, sem qualquer caso de disfunção sexual associada com o tratamento. Este trabalho constitui o primeiro estudo anatómico descritivo in vivo das artérias prostáticas, conseguido devido à utilização de técnicas de imagem nunca usadas para este fim. O uso clínico dos dados anatómicos acima referidos permitiu a implementação de técnicas de Radiologia de Intervenção no tratatamento de uma doença de elevada prevalência. ------------------------------- ABSTRACT: Benign prostatic hyperplasia (BPH) has high prevalence in men aged 50–79 years being ubiquitous with aging. Due to significant morbi-mortality associated with currently available medical and surgical treatments, there is the need for innovative technologies to continue to improve outcomes and minimize patient discomfort and morbidity. Recently, prostatic arterial embolization (PAE) was suggested as a treatmentoption for BPH based on preliminary results from animal studies and 3 treated patients. We decided to investigate if PAE might be a successful treatment option for severely symptomatic BPH patients. We performed a clinical and anatomical-radiological study in 63 patients with the use of an inovative image-guided minimally invasive technique. We evaluated 126 pelvic sides using Angio-MR or Angio-CT and Catheter Angiography before embolisation to treat symptomatic BPH. We aimed to define the main branching patterns of the male internal iliac arteries, so far only studied in the cadaver. We also evaluated the prostatic arterial supply, identifying: 1 the prostatic arteries; 2 origin and direction; 3 intra-prostatic branches; 4 anastomoses with surrounding arteries. Regarding the anatomical study we identified 181 prostatic arteries, because in 43.7% of pelvic sides 2 separate prostatic vascular pedicles were found. The most frequent origin was the internal pudendal artery (39.7%) with the common glutealpudendal trunk (21%) and superior vesical arteries (18.2%) the next commonest. Less frequent origins were the obturator artery (12.1%), the inferior (3.9%) or superior (1.7%) gluteal arteries, rectal branches from the inferior mesenteric artery (1.7%) and the accessory pudendal artery (1.7%). There were anastomoses with the surrounding arteries in 57.9% of cases: termination of the internal pudendal artery (41.6%), contralateral prostatic arteries (18.2%), same-side prostatic arteries (11.7%), rectal branches (15.6%), and vesical arteries (12.9%).Regarding the clinical study, we treated 63 patients aged 52–82 years (mean 69.5 years) who presented with symptomatic BPH refractory to medical treatment for at least 6 months. Follow-up evaluation (mean 4.7 months, range 1-12 months) was possible in 37 patients. PAE was achieved in all patients with bilateral embolization in 73%. In 27% PAE was performed unilaterally due to tortuosity, atherosclerotic changes and small size of iliac and prostatic arteries. There was a mean decrease in the IPSS of 10.8 points, a mean improvement in QoL of 1.5 points, and a mean increase in the sexual function score of 2.1 points. There was a mean PSA reduction of 30% (2.4 ng/mL), a Qmax increase of 3.1 to 3.85 mL/sec, and a mean prostate volume decrease of 21% (18.5 mL). There was one major complication: a small area of bladder wall ischemia treated by surgery. Overall, 75% of patients were considered clinical success with major improvement after PAE, while 25% of patients were considered clinical failure with little or no improvement after PAE. All remaining patients are under follow-up, stopped all prostatic medication, and reported no sexual dysfunction. This study is the first one to describe the radiological anatomy of the prostatic arteries, with the use of imaging techniques never used for this purpose before. The clinical use of the anatomical findings allowed the implementation of Interventional Radiology tehniques in the treatment of a disease with a high prevalence.

Electrospun Polyaniline-Reduced Graphene Oxide Composite Nanofibers Based High Sensitive Ammonia Gas Sensor

Ammonia is an important gas in many power plants and industrial processes so its detection is of extreme importance in environmental monitoring and process control due to its high toxicity. Ammonia’s threshold limit is 25 ppm and the exposure time limit is 8 h, however exposure to 35 ppm is only secure for 10 min. In this work a brief introduction to ammonia aspects are presented, like its physical and chemical properties, the dangers in its manipulation, its ways of production and its sources. The application areas in which ammonia gas detection is important and needed are also referred: environmental gas analysis (e.g. intense farming), automotive-, chemical- and medical industries. In order to monitor ammonia gas in these different areas there are some requirements that must be attended. These requirements determine the choice of sensor and, therefore, several types of sensors with different characteristics were developed, like metal oxides, surface acoustic wave-, catalytic-, and optical sensors, indirect gas analyzers, and conducting polymers. All the sensors types are described, but more attention will be given to polyaniline (PANI), particularly to its characteristics, syntheses, chemical doping processes, deposition methods, transduction modes, and its adhesion to inorganic materials. Besides this, short descriptions of PANI nanostructures, the use of electrospinning in the formation of nanofibers/microfibers, and graphene and its characteristics are included. The created sensor is an instrument that tries to achieve a goal of the medical community in the control of the breath’s ammonia levels being an easy and non-invasive method for diagnostic of kidney malfunction and/or gastric ulcers. For that the device should be capable to detect different levels of ammonia gas concentrations. So, in the present work an ammonia gas sensor was developed using a conductive polymer composite which was immobilized on a carbon transducer surface. The experiments were targeted to ammonia measurements at ppb level. Ammonia gas measurements were carried out in the concentration range from 1 ppb to 500 ppb. A commercial substrate was used; screen-printed carbon electrodes. After adequate surface pre-treatment of the substrate, its electrodes were covered by a nanofibrous polymeric composite. The conducting polyaniline doped with sulfuric acid (H2SO4) was blended with reduced graphene oxide (RGO) obtained by wet chemical synthesis. This composite formed the basis for the formation of nanofibers by electrospinning. Nanofibers will increase the sensitivity of the sensing material. The electrospun PANI-RGO fibers were placed on the substrate and then dried at ambient temperature. Amperometric measurements were performed at different ammonia gas concentrations (1 to 500 ppb). The I-V characteristics were registered and some interfering gases were studied (NO2, ethanol, and acetone). The gas samples were prepared in a custom setup and were diluted with dry nitrogen gas. Electrospun nanofibers of PANI-RGO composite demonstrated an enhancement in NH3 gas detection when comparing with only electrospun PANI nanofibers. Was visible higher range of resistance at concentrations from 1 to 500 ppb. It was also observed that the sensor had stable, reproducible and recoverable properties. Moreover, it had better response and recovery times. The new sensing material of the developed sensor demonstrated to be a good candidate for ammonia gas determination.

New prevalence estimate of TT virus (TTV) infection in low- and high-risk population from São Paulo, Brazil

The prevalence of TT virus (TTV) infection was investigated by Polymerase Chain Reaction (PCR) in low- (blood donors and healthy children/adolescents) and high-risk (hemophiliacs) groups from São Paulo, Brazil. Primers based on the untranslated region (UTR) of the viral genome proved to be much more ubiquitous, leading to much higher frequencies for both groups ( > or = 81%) than the earlier N22-PCR directed to the open reading frame 1 (blood donors, 5.5%, and hemophiliacs, 42.3%). The UTR-PCR also revealed an interesting profile for healthy children/adolescents: very high prevalence at the early years and significant decrease in male teenagers. The N22-PCR, in turn, demonstrated higher frequency in hemophiliacs treated with fresh blood products (58%), than in those treated with virus-inactivated clotting factors (9.4%) and blood donors (5.5%).

High prevalence of GB Virus C/Hepatitis G Virus RNA among Brazilian blood donors

The aim of this study was to investigate the presence of the Hepatitis G Virus on a population of blood donors from São Paulo, Brazil and to evaluate its association to sociodemographic variables. Two RT-PCR systems targeting the putative 5'NCR and NS3 regions were employed and the former has shown a higher sensitivity. The observed prevalence of HGV-RNA on 545 blood donors was 9.7% (CI 95% 7.4;12.5). Statistical analysis depicted an association with race/ethnicity, black and mulatto donors being more frequently infected; and also with years of education, less educated donors presenting higher prevalences. No association was observed with other sociodemographic parameters as age, gender, place of birth and of residence. DNA sequencing of nine randomly chosen isolates demonstrated the presence of genotypes 1, 2 and 3 among our population but clustering of these Brazilian isolates was not detected upon phylogenetic analysis.

Human papillomavirus genotypes in women with cervical cytological abnormalities from an area with high incidence of cervical cancer

It has been well demonstrated the relationship between the infection with high-risk human papillomavirus (HPVs) genotypes and cervical cancer. In Northeastern Argentina a high incidence of this pathology has been described and therefore a high prevalence of HPV infection is expected. In order to identify HPV genotypes associated with malignant and pre-malignant cervical lesions present in the area, 53 ecto-endo cervical cell specimens obtained from women with cytohistological alterations were studied by a PCR-RFLP technique. Out of 53 patients, 34 (64.2%) were positive for HPV infection, being HPV-16 (32.3%) the most frequently found genotype, followed by HPV-58 (14.7%), -6, -18 and -45 (5.9%), -33, -52, -53, -54, -56, -66, -MM4 and -LVX100 (2.9%). Also 5 cases of infection caused by multiple genotypes were found, which corresponded to 14.7% of the positive cases. Results indicate that besides HPV-16 and -18, the most prevalent high-risk HPV genotypes worldwide, others like -45 and -58 as well as co-infection cases are frequent between women of Northeastern Argentina, and a particular attention should be paid to this circumstance because it could be an epidemiological feature of regional importance and a useful information for a future vaccination program.

Carrion's disease (Bartonellosis bacilliformis) confirmed by histopathology in the High Forest of Peru

Bartonellosis or Carrion's disease is endemic in some regions of Peru, classically found in the inter-Andean valleys located between 500 and 3200 meters above sea level. We report the case of a 43 year-old male patient, farmer, who was born in the Pichanaki district (Chanchamayo, Junin), located in the High Forest of Peru. He presented with disseminated, raised, erythematous cutaneous lesions, some of which bled. The distribution of these lesions included the nasal mucosa and penile region. Additionally subcutaneous nodules were distributed over the trunk and extremities. Hematologic exams showed a moderate anemia. Serologic studies for HIV and Treponema pallidum were negative. The histopathologic results of two biopsies were compatible with Peruvian wart. Oral treatment with ciprofloxacin (500 mg BID) was begun. Over 10 days, the patient showed clinical improvement. This is the first report of a confirmed case of bartonellosis in the eruptive phase originating from the Peruvian High Forest, showing the geographical expansion of the Carrion's disease.

Toxoplasma-IgM and IgG-avidity in single samples from areas with a high infection rate can determine the risk of mother-to-child transmission

Anti-Toxoplasma IgG-avidity was determined in 168 serum samples from IgG- and IgM-positive pregnant women at various times during pregnancy, in order to evaluate the predictive value for risk of mother-to-child transmission in a single sample, taking the limitations of conventional serology into account. The neonatal IgM was considered the serologic marker of transmission. Fluorometric tests for IgG, IgM (immunocapture) and IgG-avidity were performed. Fifty-one of the 128 pregnant women tested gave birth in the hospital and neonatal IgM was obtained. The results showed 32 (62.75%) pregnant women having high avidity, IgM indexes between 0.6 and 2.4, and no infected newborn. Nineteen (37.25%) had low or inconclusive avidity, IgM indexes between 0.6 and 11.9, and five infected newborns and one stillbirth. In two infected newborns and the stillbirth maternal IgM indexes were low and in one infected newborn the only maternal parameter that suggested fetal risk was IgG-avidity. In the present study, IgG-avidity performed in single samples from positive IgM pregnant women helped to determine the risk of transmission at any time during pregnancy, especially when the indexes of the two tests were analysed with respect to gestational age. This model may be less expensive in developing countries where there is a high prevalence of infection than the follow-up of susceptible mothers until childbirth with monthly serology, and it creates a new perspective for the diagnosis of congenital toxoplasmosis.

High-Accuracy Low-Cost RTK-GPS for an Unmanned Surface Vehicle

This work presents a low cost RTK-GPS system for localization of unmanned surface vehicles. The system is based on the use of standard low cost L1 band receivers and in the RTKlib open source software library. Mission scenarios with multiple robotic vehicles are addressed as the ones envisioned in the ICARUS search and rescue case where the possibility of having a moving RTK base on a large USV and multiple smaller vehicles acting as rovers in a local communication network allows for local relative localization with high quality. The approach is validated in operational conditions with results presented for moving base scenario. The system was implemented in the SWIFT USV with the ROAZ autonomous surface vehicle acting as a moving base. This setup allows for the performing of a missions in a wider range of environments and applications such as precise 3D environment modeling in contained areas and multiple robot operations.

Reconstrução de Superfícies usando um Scanner 3D de Luz Estruturada

Ao longo dos últimos anos, os scanners 3D têm tido uma utilização crescente nas mais variadas áreas. Desde a Medicina à Arqueologia, passando pelos vários tipos de indústria, ´e possível identificar aplicações destes sistemas. Essa crescente utilização deve-se, entre vários factores, ao aumento dos recursos computacionais, à simplicidade e `a diversidade das técnicas existentes, e `as vantagens dos scanners 3D comparativamente com outros sistemas. Estas vantagens são evidentes em áreas como a Medicina Forense, onde a fotografia, tradicionalmente utilizada para documentar objectos e provas, reduz a informação adquirida a duas dimensões. Apesar das vantagens associadas aos scanners 3D, um factor negativo é o preço elevado. No âmbito deste trabalho pretendeu-se desenvolver um scanner 3D de luz estruturada económico e eficaz, e um conjunto de algoritmos para o controlo do scanner, para a reconstrução de superfícies de estruturas analisadas, e para a validação dos resultados obtidos. O scanner 3D implementado ´e constituído por uma câmara e por um projector de vídeo ”off-the-shelf”, e por uma plataforma rotativa desenvolvida neste trabalho. A função da plataforma rotativa consiste em automatizar o scanner de modo a diminuir a interação dos utilizadores. Os algoritmos foram desenvolvidos recorrendo a pacotes de software open-source e a ferramentas gratuitas. O scanner 3D foi utilizado para adquirir informação 3D de um crânio, e o algoritmo para reconstrução de superfícies permitiu obter superfícies virtuais do crânio. Através do algoritmo de validação, as superfícies obtidas foram comparadas com uma superfície do mesmo crânio, obtida por tomografia computorizada (TC). O algoritmo de validação forneceu um mapa de distâncias entre regiões correspondentes nas duas superfícies, que permitiu quantificar a qualidade das superfícies obtidas. Com base no trabalho desenvolvido e nos resultados obtidos, é possível afirmar que foi criada uma base funcional para o varrimento de superfícies 3D de estruturas, apta para desenvolvimento futuro, mostrando que é possível obter alternativas aos métodos comerciais usando poucos recursos financeiros.

High prevalence of malaria infection in Amazonas state, Venezuela

This study was carried out to determine the incidence of malaria in an endemic region of Amazonas State, Venezuela. For this, 200 random samples were collected from symptomatic and asymptomatic individuals from San Fernando de Atabapo and Santa Barbara. Epidemiological factors were related to malaria infection, which was diagnosed by microscopy observation and amplification of the 18S rDNA sequence by PCR. Malaria prevalence in these populations was 28.5%, whilst P. vivax and P. falciparum prevalences were 12 and 17%, respectively. No infection by P. malariae was found. A mixed infection was found on an asymptomatic individual. Prevalence patterns differed between age groups depending on the Plasmodium species. We found that 34.8% of the P. vivax and 15.2% of the P. falciparum infections were asymptomatic. The use of nets was helpful to prevent P. vivax infection, but did not protect against P. falciparum infection. The results suggest the presence of more than one mosquito vector in the area, displaying a differential pattern of infection for each Plasmodium species. There appear to be risk factors associated with malaria infections in some individuals. The population based approach and PCR diagnosis improved the accuracy of the statistical analysis in the study.

Cross sectional study reveals a high percentage of asymptomatic Plasmodium vivax infection in the Amazon Rio Negro area, Brazil

A parasitological, clinical, serological and molecular cross-sectional study carried out in a highly endemic malaria area of Rio Negro in the Amazon State, Brazil, revealed a high prevalence of asymptomatic Plasmodium vivax infection. A total of 109 persons from 25 families were studied in five villages. Ninety-nine inhabitants (90.8%) had at least one previous episode of malaria. Serology showed 85.7% and 46.9% of positivity when P. falciparum antigens and P. vivax MSP-1, respectively, were used. Twenty blood samples were PCR positive for P. vivax (20.4%) and no P. falciparum infection was evidenced by this technique. No individual presenting positive PCR reaction had clinical malaria during the survey neither in the six months before nor after, confirming that they were cases of asymptomatic infection. Only one 12 year old girl presented a positive thick blood smear for P. vivax. This is the first description of asymptomatic Plasmodium infection in this area studied.

T CD4+ cells count among patients co-infected with human immunodeficiency virus type 1 (HIV-1) and human T-cell leukemia virus type 1 (HTLV-1): high prevalence of tropical spastic paraparesis/HTLV-1-associated myelopathy (TSP/HAM)

INTRODUCTION: HIV positive patients co-infected with HTLV-1 may have an increase in their T CD4+ cell counts, thus rendering this parameter useless as an AIDS-defining event. OBJECTIVE: To study the effects induced by the co-infection of HIV-1 and HTLV-1 upon CD4+ cells. MATERIAL AND METHODS: Since 1997, our group has been following a cohort of HTLV-1-infected patients, in order to study the interaction of HTLV-1 with HIV and/or with hepatitis C virus (HCV), as well as HTLV-1-only infected asymptomatic carriers and those with tropical spastic paraparesis/HTLV-1 associated myelopathy (TSP/HAM). One hundred and fifty HTLV-1-infected subjects have been referred to our clinic at the Institute of Infectious Diseases "Emílio Ribas", São Paulo. Twenty-seven of them were also infected with HIV-1 and HTLV-1-infection using two ELISAs and confirmed and typed by Western Blot (WB) or polymerase chain reaction (PCR). All subjects were evaluated by two neurologists, blinded to the patient's HTLV status, and the TSP/HAM diagnostic was based on the World Health Organization (WHO) classification. AIDS-defining events were in accordance with the Centers for Disease Control (CDC) classification of 1988. The first T CD4+ cells count available before starting anti-retroviral therapy are shown compared to the HIV-1-infected subjects at the moment of AIDS defining event. RESULTS: A total of 27 HIV-1/HTLV-1 co-infected subjects were identified in this cohort; 15 already had AIDS and 12 remained free of AIDS. The median of T CD4+ cell counts was 189 (98-688) cells/mm³ and 89 (53-196) cells/mm³ for co-infected subjects who had an AIDS-defining event, and HIV-only infected individuals, respectively (p = 0.036). Eight of 27 co-infected subjects (30%) were diagnosed as having a TSP/HAM simile diagnosis, and three of them had opportunistic infections but high T CD4+ cell counts at the time of their AIDS- defining event. DISCUSSION: Our results indicate that higher T CD4+ cells count among HIV-1/HTLV-1-coinfected subjects was found in 12% of the patients who presented an AIDS-defining event. These subjects also showed a TSP/HAM simile picture when it was the first manifestation of disease; this incidence is 20 times higher than that for HTLV-1-only infected subjects in endemic areas.

Performances of HTLV serological tests in diagnosing HTLV infection in high-risk population of São Paulo, Brazil

Testing problems in diagnosing human T-lymphotropic virus (HTLV) infection, mostly HTLV-II, have been documented in HIV/AIDS patients. Since December 1998, the Immunology Department of Instituto Adolfo Lutz (IAL) offers HTLV-I/II serology to Public Health Units that attend HTLV high-risk individuals. Two thousand, three hundred and twelve serum samples: 1,393 from AIDS Reference Centers (Group I), and 919 from HTLV out-patient clinics (Group II) were sent to IAL for HTLV-I/II antibodies detection. The majority of them were screened by two enzyme immunoassays (EIAs), and confirmed by Western Blot (WB 2.4, Genelabs). Seven different EIA kits were employed during the period, and according to WB results, the best performance was obtained by EIAs that contain HTLV-I and HTLV-II viral lysates and rgp21 as antigens. Neither 1st and 2nd, nor 3rd generation EIA kits were 100% sensitive in detecting truly HTLV-I/II reactive samples. HTLV-I and HTLV-II prevalence rates of 3.3% and 2.5% were detected in Group I, and of 9.6% and 3.6% in Group II, respectively. High percentages of HTLV-seroindeterminate WB sera were detected in both Groups. The algorithm testing to be employed in HTLV high-risk population from São Paulo, Brazil, needs the use of two EIA kits of different formats and compounds as screening, and because of high seroindeterminate WB, may be another confirmatory assay.