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Atrioventricular valve parachute deformity is rare and is generally seen in the mitral position, called the parachute mitral valve. It is rare to see it in the tricuspid valve and up to now, there have been approximately 14 cases of parachute abnormalities in tricuspid valves in a literature review. We present here a 21-year-old male who presented to the emergency department with progressive shortness of breath over several months. Despite the absence of chest pain, palpitations, or weight changes, examination revealed a soft, holosystolic murmur at the left lower sternal border. Further investigation through electrocardiogram and echocardiogram identified a rare structural abnormality known as parachute tricuspid valve, resulting in significant tricuspid regurgitation with mild right chamber enlargement. The patient was recommended to go abroad for further management since a cardiothoracic surgeon is not available in our country.

Larissa Silva de Freitas,1,&ast; Maria Alice Freitas Queiroz,1,&ast; Luiz Fernando Almeida Machado,1 Antonio Carlos Rosário Vallinoto,1 Marluísa de Oliveira Guimarães Ishak,1 Fabiana de Almeida Araújo Santos,2 Luiz Ricardo Goulart2 ,† Ricardo Ishak1 1Laboratory of Virology, Biological Sciences Institute, Federal University of Pará, Belém, Pará, Brazil; 2Laboratory of Nanobiotechnology, Genetics and Biochemistry Institute, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil†Luiz Ricardo Goulart passed away on 24/10/2021&ast;These authors contributed equally to this workCorrespondence: Maria Alice Freitas Queiroz, Laboratory of Virology, Biological Sciences Institute, Federal University of Pará, Belém, Pará, Brazil, Tel +55 91 3201-7587, Email alicefarma@hotmail.comBackground: Chlamydia trachomatis infection is a major public health problem and the most common sexually transmitted infection in the world. Although highly prevalent, 70% to 80% of cases are asymptomatic and undiagnosed.Purpose: To overcome some limitations in terms of rapid diagnosis, phage display technology was used to bioprospect peptide mimetics of C. trachomatis immunoreactive and immunogenic antigens to be selected for the production of synthetic peptides.Methods: Initially, IgG from 22 individuals with C. trachomatis and 30 negative controls was coupled to G protein magnetic beads. The phage display technique consisted of biopanning, genetic sequencing, bioinformatics analysis and phage ELISA.Results: Clones G1, H5, C6 and H7 were selected for testing with individual samples positive and negative for C. trachomatis. Reactions were statistically significant (p < 0.05), with a sensitivity of 90.91, a specificity of 54.55, and AUC values > 0.8. One-dimensional analysis with C. trachomatis components indicated that the G1 clone aligned with cell wall-associated hydrolase domain-containing protein, the H5 clone aligned with glycerol-3-phosphate acyltransferase PlsX protein, the C6 clone aligned with a transposase and inactivated derivatives, and the H7 clone aligned with GTP-binding protein. Molecular modeling and three-dimensional analysis indicated the best fit of the four clones with a protein known as chlamydial protease/proteasome-like activity factor (CPAF), an important virulence factor of the bacterium.Conclusion: The peptides produced by phage display are related to the metabolic pathways of C. trachomatis, indicating that they can be used to understand the pathogenesis of the infection. Because of their high sensitivity and AUC values, the peptides present considerable potential for use in platforms for screening C. trachomatis infections.Keywords: C. trachomatis, phage display, mimetic peptides, CPAF, screening tests

The deterioration of concrete structures is a matter of critical concern as it threatens the durability and strength of concrete structures. Kenaf fibrous concrete composite (KFCC) can be used with advantage in new structures such as precast elements, as well as the strengthening, repair and rehabilitation of old structures to improve their durability properties. These structures are composite components, with parts as Plain concrete (PC) and others as KFCC. This study, therefore, investigated the interfacial bonding behaviour between KFCC and PC. Shear, tensile and compressive tests were carried out to measure the bond strength in shear, direct tension and compression respectively for PC to PC, PC to KFCC and KFCC to KFCC interface. Three different types of concrete grade (25, 35, and 45 MPa) were produced for the KFCC and one type of concrete grade (35 MPa) for the substrate PC. The outcome of the test showed that KFCC had an excellent interlock with the surface of the PC substrate, and thus, gives bond strength greater than the strength of PC. New concrete with the highest concrete grade of 45 MPa ensued in high compressive, tensile and shear bond strength.

Larissa S Freitas,1 Núbia Caroline C Almeida,1 Maria Alice Freitas Queiroz,1 Marcelo M Zaninotto,2 Hellen T Fuzii,3 Alfredo Ribeiro-Silva,4 Antonio CR Vallinoto,1 Marluísa OG Ishak,1 Juarez AS Quaresma,3 Ricardo Ishak1 1Virus Laboratory, Institute of Biological Sciences, Federal University of Para, 2Hospital of Clinic Gaspar Viana, 3Laboratory of Immunopathology, Nucleus of Tropical Medicine, Federal University of Para, Belém, 4Departament of Pathology, Medical School of Ribeirão Preto, University of Sao Paulo, São Paulo, Brazil Background: Chronic coronary artery disease has been associated, as a consequence of the local inflammatory reaction with previous or persistent infection with Chlamydia pneumoniae, which led to the investigation of the association of cardiovascular disease and previous infection with C. trachomatis and the role of cytokine profile (in situ) markers in the vascular system tissues. Methods: Sixty-nine biopsies were collected for immunohistochemical analysis for the presence of IL-6, IL-8, TNF-α, IFN-γ, TGF-β, and IL-10, in 16 fragments from atheromatous plaques, 32 aorta fragments, and 21 valve fragments, using a tissue microarray technique for paraffin embedded tissues. Results: Most patients undergoing revascularization surgery were men >50 years, while those undergoing valve replacement were mostly women

This article highlights the University’s strategic plan and institutionalization commitment in cultivating the green campus culture encircling the Green@UPM initiative. It presents a range of insights, lesson learned and way forward of UPM green strategies in continuously nurtures the environmentalfriendly campus atmosphere.

In this paper, an approach for real time control communication using Ethernet is proposed. The strategy to support this at the network level and include Field Programmable Gate Array (FPGA) implementation on the Ethernet platform for robotic arm. An embedded Ethernet controller is designed to send data packet via Ethernet Local Area Network (LAN). The transferring data also employs Arduino Mega as the medium of communication between FPGA board and the robotic arm. It is used as the receiver to receive data packet from FPGA board with the interface of Arduino Ethernet shield. The control operation on the robotic arm is performed once the desired data packet length is reached to the Arduino Mega. SolidWorks and MATLAB software are used to design the robotic arm and simulate the robotic arm working flexibility in real world respectively. The result of the average data packet delay between FPGA boards is lower in comparison to Arduiono board. The data packet can send successfully in through the network to test the robotic arm.

The adaptive reuse project requires complete and accurate historical information and high levels of expertise from the project team members. Within the typology of adaptive reuse projects, the ability to capture and transfer the unique set of experience from project to project is important to create the relevant knowledge. Previous adaptive reuse studies focused on project success, potential for reuse, benefits, and sustainability. However, research related to creating and transferring skills and knowledge from adaptive reuse project settings has received relatively little attention to date. The study specifically investigates the key components of knowledge transfer for the problem solving process in adaptive reuse projects. In particular, the paper seeks to establish an intellectual capital framework for adaptive reuse projects that could help the project team members transfer their knowledge during problem solving process. This study adopted the qualitative approach to data collection. The data were collected from 14 semi-structured in-depth interviews across two case studies. Data from the interviews were analyzed using content analysis for within-case analysis with the aid of Nvivo Version 9. The finding of the study highlights that the key factors of transferring knowledge were effectiveness and efficiency, similar project teams, project teams actions and sources of information on transferring of intellectual capital among project team members. The contribution of this study is the development of an intellectual capital framework for adaptive reuse projects. This framework can be used as a template for future practice and research in the field of adaptive reuse and knowledge management. In conclusion, the study enables the integration of intellectual capital and knowledge transfer theory within the specific contextual adaptive reuse project settings.

The occurrence of HTLV-I/II and HIV-1 coinfections have been shown to be frequent, probably in consequence of their similar modes of transmission. This paper presents the prevalence of coinfection of HTLV among HIV-1 infected and AIDS patients in Belém, State of Pará, Brazil. A group of 149 patients attending the AIDS Reference Unit of the State Department of Health was tested for the presence of antibodies to HTLV-I/II using an enzyme immunoassay and the positive reactions were confirmed with a Western blot that discriminates between HTLV-I and HTLV-II infections. Four patients (2.7%) were positive to HTLV-I, seven (4.7%) to HTLV-II and one (0.7%) showed an indeterminate pattern of reaction. The present results show for the first time in Belém not only the occurrence of HTLV-II/HIV-1 coinfections but also a higher prevalence of HTLV-II in relation to HTLV-I. Furthermore, it also enlarges the geographical limits of the endemic area for HTLV-II in the Amazon region of Brazil.

In this study, catalytic alumina porous medium has been fabricated by using platinum as an active material for micro-combustion application. Platinum has been deposited onto porous medium surface via wet impregnation method. The porous medium undergoes surface modification process via wash coating method using gamma alumina (γ-Al2O3) solution, before being impregnated with platinum in order to increase the surface area. The surface morphology of porous medium entirely changes from smooth “solid-rock” into rough “sand-like” after the wash coating process. The amount of platinum deposited onto the treated porous medium is 1.66 wt.%. LPG combustion analysis shows that the combustion is successfully occur inside the catalytic porous media with overall efficiency of 71%.

CCR5Δ32 and SDF1-3'A polymorphisms were investigated in a cohort of viremia controllers, without the use of therapy, along with their influence on CD4+ T lymphocytes (TLs), CD8+ TLs, and plasma viral load (VL). The samples were analyzed from 32 HIV-1-infected individuals classified as viremia controllers 1 and 2 and viremia non-controllers, from both sexes, mostly heterosexuals, paired with 300 individuals from a control group. CCR5∆32 polymorphism was identified by PCR amplification of a fragment of 189 bp for the wild-type allele and 157 bp for the allele with the ∆32 deletion. SDF1-3'A polymorphism was identified by PCR, followed by enzymatic digestion (restriction fragment length polymorphism) with the Msp I enzyme. The relative quantification of gene expression was performed by real-time PCR. The distribution of allele and genotype frequencies did not show significant differences between the groups. The gene expression of CCR5 and SDF1 was not different between the profiles of AIDS progression. There was no significant correlation between the progression markers (CD4+ TL/CD8+ TL and VL) and the CCR5∆32 polymorphism carrier status. The 3'A allele variant was associated with a marked loss of CD4+ TLs and a higher plasma VL. Neither CCR5∆32 nor SDF1-3'A was associated with viremia control or the controlling phenotype.

There is a growing need to uncover biomarkers of ionizing radiation exposure that leads to a better understanding of how exposures take place, including dose type, rate, and time since exposure. As one of the first organs to be exposed to external sources of ionizing radiation, skin is uniquely positioned in terms of model systems for radiation exposure study. The simultaneous evolution of both MS-based -omics studies, as well as in vitro 3D skin models, has created the ability to develop a far more holistic understanding of how ionizing radiation affects the many interconnected biomolecular processes that occur in human skin. However, there are a limited number of studies describing the biomolecular consequences of low-dose ionizing radiation to the skin. This review will seek to explore the current state-of-the-art technology in terms of in vitro 3D skin models, as well as track the trajectory of MS-based -omics techniques and their application to ionizing radiation research, specifically, the search for biomarkers within the low-dose range., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

The separation of biomarkers from blood is straightforward in most molecular biology laboratories. However, separation in resource-limited settings, allowing for the successful removal of biomarkers for diagnostic applications, is not always possible. The situation is further complicated by the need to separate hydrophobic signatures such as lipids from blood. Herein, we present a microfluidic device capable of centrifugal separation of serum from blood at the point of need with a system that is compatible with biomarkers that are both hydrophilic and hydrophobic. The cross-flow filtration device separates serum from blood as efficiently as traditional methods and retains amphiphilic biomarkers in serum for detection.

The description of the first human retrovirus, human T-lymphotropic virus 1 (HTLV-1), was soon associated with an aggressive lymphoma and a chronic inflammatory neurodegenerative disease. Later, other associated clinical manifestations were described, affecting diverse target organs in the human body and showing the enormous burden carried by the virus and the associated diseases. The epidemiology of HTLV-1 and HTLV-2 showed that they were largely distributed around the world, although it is possible to locate geographical areas with pockets of low and very high prevalence and incidence. Aboriginal Australians and indigenous peoples of Brazil are examples of the large spread of HTLV-1 and HTLV-2, respectively. The epidemiological link of both situations is their occurrence among isolated, epidemiologically closed or semi-closed communities. The origin of the viruses in South America shows two different branches with distinct timing of entry. HTLV-1 made its probable entrance in a more recent route through the east coast of Brazil at the beginning of the slave trade from the African continent, starting in the 16th century and lasting for more than 350 years. HTLV-2 followed the ancient route of human migration from the Asian continent, crossing the Behring Strait and then splitting in South America as the population became separated by the Andes Mountains. By that time, HTLV-2c probably arose and became isolated among the indigenous populations in the Brazilian Amazon. The study of epidemiologically closed communities of indigenous populations in Brazil allowed tracing the most likely route of entry, the generation of a new molecular subtype (HTLV-2c), the elucidation of the vertical transmission of HTLV-2, the intrafamilial aggregation of cases and the escape and spread of the virus to other areas in Brazil and abroad. Despite the burden and impact of both viruses, they are maintained as silent infections among human populations because 1, health authorities in most South American countries in which national surveillance is poor have little interest in the disease, 2, the information is commonly lost as indigenous groups do not have specific policies for HTLV and other sexually transmitted infections, and 3, health access is not feasible or properly delivered., (© The Author(s) 2020. Published by Oxford University Press.)

HTLV-1 infections are persistent and frequently latent; however, productive infections trigger different types of immunological responses that utilize cytokines to control infection. The present study investigated the role of IFNG +874A/T polymorphisms among 153 HTLV-1-infected individuals (33 clinically diagnosed with TSP/HAM, 22 with rheumatologic manifestations, 2 with dermatitis, 1 with uveitis, and 95 asymptomatic patients) and 300 healthy control individuals. Genotyping and proviral HTLV-1 load assessment were performed using real-time PCR assays, and the plasma levels of IFN-γ were measured using an enzyme immunoassay (ELISA). Genotype frequencies were not significantly different, but the presence of the T allele was higher ( p < 0.0142) among the asymptomatic patients. Plasma levels of IFN-γ were significantly higher ( p < 0.0137) among those with the TT genotype. Their proviral load was also higher, although this elevation did not reach statistical significance. There was no difference in the IFN-γ plasma levels among the symptomatic patients, even when ranked according to disease severity (TSP/HAM or rheumatologic manifestations). However, the difference among asymptomatic patients with the T allele was significantly higher ( p < 0.0016) and similar to the plasma levels observed among symptomatic individuals. These results suggest that the IFNG +874A/T polymorphism may modulate the plasma levels of IFN-γ during HTLV-1 infection. Asymptomatic carriers of the polymorphic genotypes appear to develop an inflammatory response in a shorter timeframe, triggering progression to HTLV-1-related symptoms and disorders. These results further suggest that HTLV-1-infected asymptomatic individuals expressing the IFNG +874A/T polymorphism should be monitored more closely in order to readily detect the increase in clinical symptoms, as these patients are potentially at risk of a poor prognosis and should therefore start available treatment procedures earlier.

Infectious agents are common companions of humans and since ancient times they follow human migration on their search for a better place to live. The study of paleomicrobiology was significantly improved in its accuracy of measurement with the constant development of better methods to detect and analyze nucleic acids. Human tissues are constantly used to trace ancient infections and the association of anthropological evidences are important to confirm the microbiological information. Infectious agents which establish human persistent infections are particularly useful to trace human migrations. In the present article, the evidence of infection by viral agents such as human T-lymphotropic virus 1, human T-lymphotropic virus 2, human herpes virus-8, JC virus, and a bacterium, Chlamydia trachomatis , was described using different methodologies for their detection. Their presence was further used as biomarkers associated with anthropological and other relevant information to trace human migration into the Amazon region of Brazil. The approach also evidenced their microbiological origin, emergence, evolution, and spreading. The information obtained confirms much of the archeological information available tracing ancient and more recent human migration into this particular geographical region. In this article, the paleomicrobiological information on the subject was summarized and reviewed.

Background: The present study aimed to describe the genetic diversity of HIV-1, as well as the resistance profile of the viruses identified in HIV-1 infected pregnant women under antiretroviral therapy in the state of Pará, Northern Brazil., Methods: Blood samples were collected from 45 HIV-1 infected pregnant to determine the virus subtypes according to the HIV-1 protease (PR) gene and part of the HIV-1 reverse transcriptase (RT) gene by sequencing the nucleotides of these regions. Drug resistance mutations and susceptibility to antiretroviral drugs were analyzed by the Stanford HIV Drug Resistance Database., Results: Out of 45 samples, only 34 could be amplified for PR and 30 for RT. Regarding the PR gene, subtypes B (97.1%) and C (2.9%) were identified; for the RT gene, subtypes B (90.0%), F (6.7%), and C (3.3%) were detected. Resistance to protease inhibitors (PI) was identified in 5.8% of the pregnant, and mutations conferring resistance to nucleoside reverse transcriptase inhibitors were found in 3.3%, while mutations conferring resistance to non-nucleoside reverse transcriptase inhibitors were found in 3.3%., Conclusions: These results showed a low frequency of strains resistant to antiretroviral drugs, the prevalence of subtypes B and F, and the persistent low transmission of subtype C in pregnant of the state of Pará, Brazil.

The presence of the single nucleotide polymorphisms in exon 1 of the mannose-binding lectin 2 (MBL2) gene was evaluated in a sample of 159 patients undergoing coronary artery bypass surgery (71 patients undergoing valve replacement surgery and 300 control subjects) to investigate a possible association between polymorphisms and heart disease with Chlamydia infection. The identification of the alleles B and D was performed using real time polymerase chain reaction (PCR) and of the allele C was accomplished through PCR assays followed by digestion with the restriction enzyme. The comparative analysis of allelic and genotypic frequencies between the three groups did not reveal any significant difference, even when related to previous Chlamydia infection. Variations in the MBL plasma levels were influenced by the presence of polymorphisms, being significantly higher in the group of cardiac patients, but without representing a risk for the disease. The results showed that despite MBL2 gene polymorphisms being associated with the protein plasma levels, the polymorphisms were not enough to predict the development of heart disease, regardless of infection with both species of Chlamydia.

The dental pulp is a sterile highly vascularized tissue and has been commonly used as a biological material to detect the genome of infectious agents that reach the dental tissue. Indeed, the pulp is also used to reveal past and ancient infections in the field of paleomicrobiology. The present study aimed to detect the presence of Hepatitis C virus (HCV) in a small community (approximately 400 inhabitants) in the Amazon region of Brazil (Nossa Senhora do Perpetuo Socorro, Vizeu, Para, Brazil) and standardize a technique for the detection of the virus in the dental pulp. Serum samples were collected from 48 patients whose teeth were clinically recommended for surgical extraction. The group comprised an equal number of males and females, mostly agriculture workers and housewives, respectively. The majority (64.6%) received less than one minimum wage and were ill educated (less than four years of school years). An enzyme immune assay was used to detect antibodies to HCV and the 9 (18.8%) positive samples were submitted to nucleic acid extraction in the blood (using the EXTRAzol) and the pulp (QIAamp DNA Micro Kit e kit RNeasy Plus Micro). The pulp was removed using a modified protocol without the use of liquid nitrogen. Nucleic acid was found in 8 of the dental pulp, but in 7 of the blood samples. Sequencing of one of the samples showed the presence of genotype 1., Conclusions: A novel simplified methodology for the extraction and amplification of HCV nucleic acid was successful to detect the presence of persistent infections of the virus within the dental pulp tissue. The protocol may be helpful to detect past and ancient infections and to better understand the natural history of HCV., Competing Interests: The authors have declared that no competing interests exist.

The present study investigated the association between the rs12979860 polymorphism in the IL-28B gene and HTLV-1 infection as well as the development of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). HTLV-1-infected patients (26 HAM/TSP symptomatic and 53 asymptomatic) and 300 seronegative healthy controls were investigated. Plasma levels of the cytokines TNF-α, TNF-β, IL-8, IL-10, IL-6, and IFN-γ from infected patients were measured using an indirect enzyme-linked immunosorbent assay. The HTLV proviral load was measured using a real-time PCR assay, and T-cell subset counts were determined by flow cytometry. Real-time PCR was used to genotype the rs12979860 SNP. The allelic and genotypic distributions displayed no significant differences among the investigated groups. No significant association between the serum cytokine levels and the presence of the rs12979860 SNP in symptomatic and asymptomatic subjects was observed. A positive correlation (p = 0.0015) between TNF-β and IFN-γ was observed in the asymptomatic group, but a positive correlation was only observed (p = 0.0180) between TNF-α and IL-6 in the HAM/TSP group. The proviral load was significantly higher in HAM/TSP patients than in asymptomatic subjects. The present results do not support a previous report indicating an association between the SNP rs12979860 and HAM/TSP outcome.

The present study assessed the phenotypic aspects of oral-cavity Candida albicans isolates from 300 HIV-1- positive patients, relating the most commonly investigated virulence factors (enzyme typing and germ-tube formation) to the most common morphotypes. The samples were seeded into specific media for isolation and subsequent identification using the automated Vitek 2 system. The following assays were performed for phenotypic characterization: morphotyping, germ-tube formation and enzyme typing. Out of 300 collected samples, 144 tested positive for yeasts of the Candida genus, 98 (32.7 %) of which were identified as C. albicans. The latter samples were attributed to seven different morphotypes; the three most common morphotypes were 7208 (49 %), 7308 (14.3 %) and 3208 (13.3 %). All of the C. albicans isolate samples formed germ tubes and produced the enzymes proteinase and phospholipase, with an activity classified as intermediate to high. Due to the identification of virulence factors among the analyzed samples, monitoring of HIV-1-positive patients colonized by different morphotypes must be established because these morphotypes are extremely pathogenic and can trigger severe fungal infections.

This study evaluated the relative occurrences of BK virus (BKV) and JC virus (JCV) infections in patients with chronic kidney disease (CKD). Urine samples were analysed from CKD patients and from 99 patients without CKD as a control. A total of 100 urine samples were analysed from the experimental (CKD patients) group and 99 from the control group. Following DNA extraction, polymerase chain reaction (PCR) was used to amplify a 173 bp region of the gene encoding the T antigen of the BKV and JCV. JCV and BKV infections were differentiated based on the enzymatic digestion of the amplified products using BamHI endonuclease. The results indicated that none of the patients in either group was infected with the BKV, whereas 11.1% (11/99) of the control group subjects and 4% (4/100) of the kidney patients were infected with the JCV. High levels of urea in the excreted urine, low urinary cellularity, reduced bladder washout and a delay in analysing the samples may have contributed to the low prevalence of infection. The results indicate that there is a need to increase the sensitivity of assays used to detect viruses in patients with CDK, especially given that polyomavirus infections, especially BKV, can lead to a loss of kidney function following transplantation.

Objective: This study investigated the association of the single nucleotide polymorphisms (SNPs) in the FAS and FASL genes with the outcome of hepatitis B virus (HBV) infection., Methods: Blood samples were collected from 116 HBV-infected patients at the Hospital of the Santa Casa de Misericordia Foundation (Belém, PA, Brazil). Seronegative individuals were used as controls. DNA samples were extracted from the leukocytes and assayed using the polymerase chain reaction (PCR) followed by RFLP analysis with restriction endonucleases., Results: The frequencies of the mutant genotypes for -670FAS (GG), Ivs2nt-124FASL (GG), Ivs3nt-169FASL (ΔT/ΔT), and -844FASL (TT) were higher in the HBV patients, and the FAS-1377AA genotype was more frequent in the control group; however, the differences between the allele and genotype frequencies were not statistically significant. When the HBV patient population was divided into two groups (inactive carriers and active chronic hepatitis patients), the mutant genotypes were found to be more prevalent in the active chronic hepatitis group with respect to the FAS gene polymorphisms; however, this difference was not statistically significant., Conclusions: The results suggest that the polymorphisms in FAS and FASL genes are not associated with HBV infection or even with the natural history of the infection in the Brazilian Amazon region.

The present study investigated the prevalence of the polymorphisms in the exon 1 of the MBL2 gene in patients with tuberculosis at a hospital in northern Brazil, which is a regional reference for the treatment of the disease. The study group was composed of 167 patients with tuberculosis, 34 of which had the extra-pulmonary form of the disease, while the other 133 had the pulmonary type. The control group consists of 159 healthy individuals. Samples of DNA extracted from leucocytes were submitted to Polymerase Chain Reaction for the amplification of a 120-bp segment of exon 1 of the MBL2 gene. The distribution of allele and genotype frequencies varied little among the different groups, and it was not possible to establish any clear association between the variants of the MBL2 gene and the susceptibility to or clinical profile of tuberculosis infections in the population analyzed., (Copyright © 2012 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.)

This study aimed to describe the epidemiological, immunological and molecular features of infection by the human T-lymphotropic virus-1/2 (HTLV-1/2) in individuals with HIV-1 in an urban area of Piaui State, Brazil. Exclusion criteria included patients under 18 years of age, pregnant women or Amerindians. Of 805 individuals analyzed by the serological method (ELISA) for the detection of anti-HTLV-1/2, 18 (2.24%) were positive, but only 13 (1.61%) were confirmed by PCR. The RFLP analysis revealed that nine (1.12%) of these subjects were positive for HTLV-1 and four (0.5%) for HTLV-2. The mean age of these co-infected individuals was 50.9±9.1 years, and a significant association was found with age (above 40 years: p = 0.002), minor surgeries (p = 0.004) and blood transfusion (p = 0.031). Quantification of the T CD4+/CD8+ lymphocytes and the HIV-1 viral load showed no significant association of T CD8 + lymphocyte levels with co-infection in the patients with HIV-1/HTLV-1. The sequencing of the LTR region and phylogenetic analysis indicated that the nine HTLV-1 strains belong to the Transcontinental subgroup of the Cosmopolitan group (1a), with a 83% (neighbor-joining) bootstrap value. The HTLV-2 strains were identified as subtype HTLV-2c, supported by a bootstrap value of 79%. Further studies in other population subgroups, such as blood donors and drug users, will be necessary to clarify the dissemination of HTLV-1/2 in Piau and elucidate the developmental profile of the virus in the region.

FAS and FASLG genes are closely linked to the apoptosis mechanism of the immune system and several polymorphisms in these genes have been associated with susceptibility to diseases. The present study investigated the polymorphisms at positions -670 in the FAS gene, and -169 and -124 in the FASLG gene, among HTLV-1 infected subjects. Blood samples from HTLV infected subjects and seronegative individuals were collected, and polymorphisms were analyzed using a polymerase chain reaction (PCR) followed by RFLP analysis using restriction endonucleases. The genotype frequencies of the FAS -670 polymorphism was the only one that showed a higher and significant prevalence of genotype -670GG among HTLV-1 infected subjects as compared to the control group (p=0.0160), but the genotype -670AA was more frequent among TSP/HAM patients as compared to the asymptomatic individuals (p=0.0005). TCD4(+) and TCD8(+) lymphocyte counts from HTLV infected and seronegative subjects, as well as the proviral load values, according to the status of symptomatic and asymptomatic infection carrying different genotypes were compared but showed no statistical significance. The present results suggest that FAS -670 polymorphism seems to be associated with susceptibility to HTLV-1 and may increase the chance to develop TSP/HAM among HTLV-1 infected persons., (Copyright © 2011 Elsevier B.V. All rights reserved.)

The present study investigated the prevalence of infection by JC and BK polyomaviruses (JCV and BKV) in patients with chronic renal disease (CRD), kidney transplant recipients, and a control group of asymptomatic subjects. We tested a total of 295 urine samples. After DNA extraction, polymerase chain reaction assay was used to amplify a fragment of 173 bp of the polyomavirus T antigen, followed by analysis using the BamHI restriction endonuclease. Infection by polyomavirus was detected in 17.6% (52/295 subjects) of the subjects. Whereas 30.5% (18/59) of transplant recipients were infected, the frequency was only 22.4% (30/134) in the control subjects, and 3.9% (4/102) in the CRD group (all JCV). The vast majority of infections (88.9%; 16/18) in transplant recipients were of the BKV type, whereas this type was absent in CRD patients, and made up only 10.0% (3/30) of infections in the control group. The risk of BKV infection was 72 times greater in renal transplant patients than in asymptomatic subjects. The low frequency of infection found in CRD patients may have been related to elevated levels of urea excreted in the urine, together with reduced urine volume and cell content. These factors may combine to reduce viral load or inhibit amplification. The results of the study indicate a need for the routine screening for polyomavirus in pre- and post-transplant patients, as well as organ donors, considering that BKV infection has been associated with graft rejection in kidney transplants., (© 2011 John Wiley & Sons A/S.)

Introduction: The present study investigated the association between mannose-binding lectin (MBL) gene polymorphism and serum levels with infection by HIV-1., Methods: Blood samples (5 mL) were collected from 97 HIV-1-infected individuals resident in Belém, State of Pará, Brazil, who attended the Special Outpatient Unit for Infections and Parasitic Diseases (URE-DIPE). CD4+ T-lymphocyte count and plasma viral load were quantified. A 349bp fragment of exon 1 of the MBL was amplified via PCR, using genomic DNA extracted from controls and HIV-1-infected individuals, following established protocols. MBL plasma levels of the patients were quantified using an enzyme immunoassay kit., Results: Two alleles were observed: MBL*O, with a frequency of 26.3% in HIV-1-infected individuals; and the wild allele MBL*A (73.7%). Similar frequencies were observed in the control group (p > 0.05). Genotype frequencies were distributed according to the Hardy-Weinberg equilibrium in both groups. Mean MBL plasma levels varied by genotype, with statistically significant differences between the AA and AO (p < 0.0001), and AA and OO (p < 0.001) genotypes, but not AO and OO (p = 0.17). Additionally, CD4+ T-lymphocytes and plasma viral load levels did not differ significantly by genotype (p > 0.05)., Conclusions: The results of this study do not support the hypothesis that MBL gene polymorphism or low plasma MBL concentrations might have a direct influence on HIV-1 infection, although a broader study involving a large number of patients is needed.

Regarding the importance of interferon-gamma (IFN-gamma) in protective immunity against Mycobacterium tuberculosis and the functional role of IFNG +874T/A single nucleotide polymorphism (SNP) in the IFN-gamma production, the present study investigated the relationship of this genetic polymorphism with susceptibility to tuberculosis (TB). A total of 129 patients with pulmonary tuberculosis (PTB), 33 with extrapulmonary tuberculosis (EPTB), and 156 control subjects were studied. Blood samples were drawn and plasma was used to measure IFN-gamma serum concentration by enzyme-linked immunoassay. DNA samples were extracted from leukocytes and used to investigate +874T/A polymorphism in IFNG gene using allele-specific oligonucleotide-polymerase chain reaction. An association between the presence of the allele +874A and the genotype +874AA with the active tuberculosis was found (p < 0.0001, 95% confidence interval = 1.64-3.22), at the same time that allele + 874T and genotype +874T/T were more frequent in the control group. The average plasma concentration of IFN-gamma among patients with tuberculosis was significantly lower than in the control group, and were lower in the EPTB group than in the group with PTB, suggesting a relationship of low plasma levels of this cytokine with active tuberculosis and the progression to more serious forms of the disease. Furthermore, we observed the association of the +874T/T and +874A/A genotypes with high and low IFN-gamma plasma concentrations, respectively, both in TB patients and in the control groups. Thus our findings suggest an association of the IFNG +874T/A polymorphism with susceptibility to M. tuberculosis infection in the studied population., (Copyright 2010 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.)

The molecular epidemiology of HIV-1 strains circulating in Belem-PA and Macapa-AP, in the Northern region of Brazil, is described using sequences of the C2V3 segment of the env and the pro gene of HIV-1 from patients of the Reference Unit for Special Infectious and Parasitary Diseases (URE-DIPE) in Belem-PA and the Central Laboratory (LACEN) in Macapa-AP. Subtype B was the most frequently found in relation to pro (88.3%) in Belem and in Macapa (97.1%) and env (88.3% in Belem and 100% in Macapa). Subtype F was also described in Belem (9.3% pro and 8.3% env) and Macapa (2.8% pro). Subtype D was described for the first time in the Northern region of the country as well as the recent entry of CRF02&#95;AG. Furthermore, several possible recombinant forms among the various subtypes were found in both cities. The results support the hypothesis that HIV-1 infection is associated with the epidemic of the virus in the Southeast region of the country and that the city of Belem is the most important route for HIV-1 entry in the Northern region of Brazil.

The present study compares the genotype frequencies between two population groups composed by 73 hepatitis C virus (HCV)-infected patients and 92 seronegative controls and investigates the role of allele variants as a possible factor in the susceptibility to HCV infection and the influence on disease progression. The identification of MBL*B and MBL*C alleles was performed by restriction fragment length polymorphism analysis of the 349-bp product using BanI and MboII restriction enzymes, respectively, and a polymerase chain reaction-sequence-specific polymorphism for discrimination of MBL*D. The analysis of allele and genotype frequencies between an HCV-infected group and seronegative controls did not indicate significant differences. The comparison of chronically infected subjects with and without liver cirrhosis was also not statistically significant. The odds ratio estimations were not significant, and the values obtained cannot suggest that the presence of allele variant MBL*B could have some influence in the risk of HCV infection progression to liver cirrhosis and that the presence of allele MBL*D could confer some protection against disease progression, but a larger sample size is necessary to confirm the present results.

The present study investigated the prevalence of mutations in the -550 (H/L) and -221 (X/Y) mannose-binding lectin (MBL) gene promoter regions and their impact on infection by human immunodeficiency virus 1 (HIV-1) in a population of 128 HIV-1 seropositive and 97 seronegative patients. The allele identification was performed through the sequence-specific primer polymerase chain reaction method, using primer sequences specific to each polymorphism. The evolution of the infection was evaluated through CD4+ T-lymphocyte counts and plasma viral load. The allele and haplotype frequencies among HIV-1-infected patients and seronegative healthy control patients did not show significant differences. CD4+ T-lymphocyte counts showed lower levels among seropositive patients carrying haplotypes LY, LX and HX, as compared to those carrying the HY haplotype. Mean plasma viral load was higher among seropositive patients with haplotypes LY, LX and HX than among those carrying the HY haplotype. When promoter and exon 1 mutations were matched, it was possible to identify a significantly higher viral load among HIV-1 infected individuals carrying haplotypes correlated to low serum levels of MBL. The current study shows that haplotypes related to medium and low MBL serum levels might directly influence the evolution of viral progression in patients. Therefore, it is suggested that the identification of haplotypes within the promoter region of the MBL gene among HIV-1 infected persons should be further evaluated as a prognostic tool for AIDS progression.

The present study investigated the frequency of the mutations at positions -550 and -221 of the mannose-binding lectin (MBL) gene in a sample of 75 human T-cell lymphotropic virus (HTLV) infected patients and 96 HTLV seronegative controls, in order to evaluate the occurrence of a possible association between the polymorphism and HTLV infection. A sequence specific primer-polymerase chain reaction was used for discrimination of the polymorphism. The analysis of allele frequencies at position -550 did not show any significant differences between HTLV infected group and controls, but there was a significant difference at position -221. The comparative analysis of haplotypes frequencies were not significant, but the genotype frequencies between the two groups, revealed a higher prevalence of genotype LYLX (25.3%), associated with medium and low MBL serum levels among HTLV infected subjects. The odds ratio estimation demonstrated that the presence of genotype LYLX was associated with an increased risk of HTLV infection (p = 0.0096; 1.38 < or = IC95% < or = 7.7605). There was no association between proviral load and the promoter polymorphism, but when promoter and exon 1 mutations were matched, it was possible to identify a significant higher proviral load among HTLV infected individuals carrying haplotypes correlated to low serum levels of MBL. The present study shows that the polymorphism in the promoter region of the MBL gene may be a genetic marker associated with HTLV infection, and emphasizes the need for further studies to determinate if the present polymorphism have any impact on diseases linked to HTLV infection.

Previous serological studies on the Arara do Laranjal Indian group revealed extensive HTLV-2 infections. A collection of 97 new samples from the Arara were found repeatedly negative using three different commercial enzyme immunoassays. Eight samples that exhibited optical density readings close to the cut-off value were re-evaluated using Western blot (GeneLab 2.4, Singapore) assay. One sample was found to be non-reactive, five exhibited indeterminate patterns, one was classified as HTLV, and one was confirmed as HTLV-2. Peripheral blood mononuclear cell DNA of the eight samples were subjected to nested PCR and restriction fragment length polymorphism (RFLP) analysis of the pX and env regions, and nucleotide sequencing of the 5'-LTR region. All produced amplification products of pX, but env could be amplified in only one sample with the commonly used primers. RFLP analysis of the pX region using TaqI confirmed HTLV-2 infection. Nucleotide sequencing of the 5'-LTR region was performed in three samples (HTLV-2, HTLV and indeterminate based on Western blot pattern). Phylogenetic analysis of a 449-nt fragment using the Neighbour-Joining method clearly demonstrated that the three samples clustered within the HTLV-2c molecular subtype. The present study confirms the wide dissemination of the HTLV-2c subtype among linguistically and culturally distinct Amazonian Indian groups, and emphasizes the unique occurrence of infection by this subtype in Brazil. Moreover, it emphasizes the limitation of employing the present serological screening assays in blood banks, epidemiological studies, and the importance of molecular assays in the confirmatory procedures for the primary detection of HTLV-2 infections.

The seroprevalence and the occurrence of an HIV-1 subtype was assessed in blood samples of the Tiriyo tribe. Antibody was found in 0.6% and the molecular analysis of the pro region detected the emergence of a subtype B for the first time in a native Indian tribe of the Amazon region of Brazil.

The present study evaluated the occurrence of HTLV-1 and its subtypes in blood samples of patients presenting symptoms of tropical spastic paraparesis/HTLV-1 associated myelopathy. The detection of HTLV infection was performed by serological and molecular assays. Five patients were infected by HTLV-1 of the Cosmopolitan subtype, subgroup Transcontinental. The results confirm the occurrence of HTLV-1 infection among patients with clinical diagnosis of tropical spastic paraparesis/HTLV-1 associated myelopathy in Belém, Pará.

Antibodies to human T-cell lymphotropic virus-1 and 2 (HTLV-1 and 2) were tested in 259 inhabitants (98 males and 161 females) of four villages of the Marajó Island (Pará, Brazil) using enzyme immunoassays (ELISA and Western blot). Types and subtypes of HTLV were determined by nested polymerase chain reaction (PCR) targeting the pX, env and 5 LTR regions. HTLV-1 infection was detected in Santana do Arari (2.06%) and Ponta de Pedras (1%). HTLV-2 was detected only in Santana do Arari (1.06%). Sequencing of the 5 LTR region of HTLV-1 and the phylogenetic analysis identified the virus as a member of the Cosmopolitan Group, subgroup Transcontinental. Santana do Arari is an Afro-Brazilian community and the current results represent the first report of HTLV-1 infection in a mocambo located in the Brazilian Amazon region.

The present study investigated the association between mannose-binding lectin (MBL) gene polymorphism and the susceptibility to human T-cell lymphotropic virus (HTLV) infection in a group of 83 HTLV-infected asymptomatic subjects (62 HTLV-1 and 21 HTLV-2) and 99 healthy controls. Detection of MBL*A, MBL*B, and MBL*C was performed by amplifying a fragment of 349 bp (exon 1) and submitting the product to restriction fragment length polymorphism analysis with BanI and MboII endonucleases. Allele MBL*D was investigated by sequence-specific primer-polymerase chain reaction. The frequency of MBL*A, MBL*B, and MBL*D was 63%, 22%, and 15% among seropositive subjects and 70%, 14%, and 16% among healthy controls, respectively. Genotype differences were statistically significant (chi2 = 11.57; p = 0.04); the presence of genotype BB was 9.6% among HTLV-infected patients compared with 1% among controls (chi2 = 7.151; p = 0.019). A significant difference of the genotype frequencies between HTLV-1 and HTLV-2 infections was observed, but this result could be attributed to the number of investigated HTLV-1-infected subjects. The odds ratio to the presence of BB genotype was 10.453 (1.279 < or = IC95% < or = 85.40; p = 0.019). Results reveal a strong association between MBL polymorphism and HTLV infection. Presence of genotype BB may be associated with the susceptibility to HTLV, but further studies, with a larger number of individuals, will be necessary. MBL polymorphism could possibly have an impact on diseases associated with HTLV infection.

The present work evaluated the epidemiology of human immunodeficiency virus 1/human T-cell lymphotropic virus (HIV-1/HTLV) coinfection in patients living in Belém (state of Pará) and Macapá (state of Amapá), two cities located in the Amazon region of Brazil. A total of 169 blood samples were collected. The sera were tested by enzyme-linked immunosorbent assay to determine the presence of antibodies anti-HTLV-1/2. Confirmation of infection and discrimination of HTLV types and subtypes was performed using a nested polymerase chain reaction targeting the pX and 5' LTR regions, followed by restriction fragment length polymorphism and sequencing analysis. The presence of anti-HTLV1/2 was detected in six patients from Belém. The amplification of the pX region followed by RFLP analysis, demonstrated the presence of HTLV-1 and HTLV-2 infections among two and four patients, respectively. Sequencing HTLV-1 5' LTR indicated that the virus is a member of the Cosmopolitan Group, Transcontinental subgroup. HTLV-2 strains isolated revealed a molecular profile of subtype HTLV-2c. These results are a reflex of the epidemiological features of HIV-1/HTLV-1/2 coinfection in the North region of Brazil, which is distinct from other Brazilian regions, as reported by previous studies.

Human T-lymphotropic virus type I (HTLV-I) infection was investigated in 168 Japanese immigrants (64 males and 104 females) living in the Tome-Acu county located in the State of Para, Brazil. The serological screening was performed using an enzyme-linked immunosorbent assay, and showed the presence of anti-HTLV in four women whose ages ranged from 50 to 88. Confirmation of infection and discrimination HTLV typing was performed using a nested PCR on the extracted DNA targeting the pX region. In three of the samples, infection was confirmed to be HTLV-I. Sequencing HTLV-I 5'LTR and the RFLP pattern using DraI and SacI endonucleases indicated that the virus is a member of the Cosmopolitan group. These three women originated from the Kyushu region, though two of the corresponding HTLV-I strains were phylogenetically related to the Japanese subgroup and the third to the Transcontinental subgroup, which probably reflects the geographical origin of the infected individuals. The Japanese community residing in the northern Brazil apparently have not contributed to increase the prevalence of HTLV-I in the country.

Molecular characterization of human T-cell lymphotropic virus II (HTLV-II) isolates in North America and Europe has shown the existence of two principal subtypes of the virus, HTLV-IIa and HTLV-IIb. Subsequent studies on HTLV-II isolates from Brazil have suggested the existence of a unique variant phylogenetically related to HTLV-IIa but phenotypically similar to HTLV-IIb with respect to the transactivatory protein, Tax. This variant has been designated HTLV-IIc. To better clarify the variability and distribution of HTLV-II in Brazil, the viruses present in two population groups from the Amazon region were tested for the presence of HTLV-II using serological and molecular assays. The groups consisted of blood donors from three Amerindian communities and of HIV-1/HTLV-II coinfected patients residing in Belém, an urban area. Nucleotide sequences and phylogenetic analysis confirmed the presence of HTLV-IIc subtype among Amerindian populations and, for the first time, the presence of the same virus among urban groups in Belém. The isolated occurrence of the HTLV-IIc subtype among Amerindian populations in the Amazon region could be attributed to (1) the different migratory pathways and founder effect, or (2) the local origin of a proto-HTLV-II carried by Amerindian ancestors who migrated to the Amazon circa 11,000 to 13,000 years ago. These results suggest that not only is HTLV-IIc unique to this region, but that its presence in urban areas of Brazil has resulted from admixture processes during the colonization of the country.

Three patients (males, black, ages 37, 40 and 57) attended a university clinic with a progressive paraparesis of obscure origin. One patient who referred disease duration of more than 16 years, showed diminished deep reflexes, bilateral Babinski's sign, diminished sensation of vibration, abnormal bladder function and back pain. The other two patients (with one and six years of disease duration) complained of weakness in one leg, increased deep reflexes and back pain. Babinski's sign and bladder disturbance were also present in the patient with six years of disease. Blood samples tested by an enzyme immune assay and a discriminatory Western blot were positive for HTLV-I. The familial analysis of one patient showed a possible pattern of sexual and vertical transmission of the virus. To the best of our knowledge, these are the first cases of a proven association between HTLV-I and TSP/HAM in Belem, Para, and emphasize the need to actively look for cases of neurological disease associated to the virus.

Blood samples from native Indians in the Kararao village (Kayapo), were analysed using serological and molecular methods to characterize infection and analyse transmission of HTLV-II. Specific reactivity was observed in 3/26 individuals, of which two samples were from a mother and child. RFLP analysis of the pX and env regions confirmed HTLV-II infection. Nucleotide sequence of the 5' LTR segment and phylogenetic analysis showed a high similarity (98%) between the three samples and prototype HTLV-IIa (Mot), and confirmed the occurrence of the HTLV-IIc subtype. There was a high genetic similarity (99.9%) between the mother and child samples and the only difference was a deletion of two nucleotides (TC) in the mother sequence. Previous epidemiological studies among native Indians from Brazil have provided evidence of intrafamilial and vertical transmission of HTLV-IIc. The present study now provides molecular evidence of mother-to-child transmission of HTLV-IIc, a mechanism that is in large part responsible for the endemicity of HTLV in these relatively closed populations. Although the actual route of transmission is unknown, breast feeding would appear to be most likely.

Knowledge is limited on the spread of bacteria from genus Chlamydia in Brazil. This study included a sero-epidemiological survey of 2,086 samples from native Indian populations of the Brazilian Amazon region. Sera were screened using indirect immunofluorescence assay for detection of antibodies to C. trachomatis serotype L2, followed by microimmunofluorescence assay using fifteen C. trachomatis and C. pneumoniae serotypes as antigen substrates. Antibody prevalence was 48.6%, but there was a large prevalence range among the groups, including those that had never been challenged with the bacteria, as well as those in which almost all individuals had been infected. Titration of IgG antibodies and detection of specific IgM in high-titer samples showed the persistence of Chlamydia in 6.1% of the reactive individuals, who probably play an important role as reservoirs for dissemination of the bacteria. Specific seroreactivity to C. trachomatis showed the presence of serotypes A, B, Ba, D, E, G, H, I, and L1 in the geographic area surveyed. Furthermore, the survey showed that C. pneumoniae was also infecting these individuals. Both species may be involved in a significant human disease burden that merits further clarification.

The human lymphotropic viruses type I (HTLV-I) and type II (HTLV-II) are members of a group of mammalian retroviruses with similar biological properties, and blood transfusion is an important route of transmission. HTLV-I is endemic in a number of different geographical areas and is associated with several clinical disorders. HTLV-II is endemic in several Indian groups of the Americas and intravenous drug abusers in North and South America, Europe and Southeast Asia. During the year of 1995, all blood donors tested positive to HTLV-I/II in the State Blood Bank (HEMOPA), were directed to a physician and to the Virus Laboratory at the Universidade Federal do Pará for counselling and laboratory diagnosis confirmation. Thirty-five sera were tested by an enzyme immune assay, and a Western blot that discriminates HTLV-I and HTLV-II infection. Two HTLV-II positive samples were submitted to PCR analysis of pX and env genomic region, and confirmed to be of subtype IIa. This is the first detection in Belém of the presence of HTLV-IIa infection among blood donors. This result emphasizes that HTLV-II is also present in urban areas of the Amazon region of Brazil and highlights the need to include screening tests that are capable to detect antibodies for both types of HTLV.

Human T lymphotropic virus, type II (HTLV-II), infection has been shown to be endemic in a number of American Indian populations, and high rates of infection have also been documented in intravenous drug abusers in urban areas throughout the world. Although the role of HTLV-II in human disease has yet to be clearly defined, there is accumulating evidence that like HTLV-I, infection may also be associated with rare lymphoproliferative and neurological disorders. In this article we review and summarize the epidemiology, molecular properties and clinical features of HTLV-II infection.

The Amazon region of Brazil is an area of great interest because of the large distribution of hepatitis B virus in specific Western areas. Seven urban communities and 24 Indian groups were visited in a total of 4,244 persons. Each individual was interviewed in order to obtain demographic and familial information. Whole blood was collected for serology and genetic determinations. Eleven genetic markers and three HBV markers were tested. Among the most relevant results it was possible to show that (i) there was a large variation of previous exposure to HBV in both urban and non-urban groups ranging from 0 to 59.2%; (ii) there was a different pattern of epidemiological distribution of HBV that was present even among a same linguistic Indian group, with mixed patterns of correlation between HBsAg and anti-HBs and (iii) the prevalence of HBV markers (HBsAg and anti-HBs) were significantly higher (P = 0.0001) among the Indian population (18.8%) than the urban groups (12.5%). It is possible that the host genetic background could influence and modulate the replication of the virus in order to generate HB carrier state.

Human T cell lymphotropic virus type II (HTLV-II) infection is endemic in a number of indigenous populations in North, Central, and South America. In the present study we have employed serological and molecular methods to identify HTLV-II infection in Indian communities in the Amazon region of Brazil. Sera (1324) from 25 different Indian communities were analyzed by ELISA and Western blot. One hundred and four samples (7.8%) from a number of culturally distinct and geographically unrelated populations were found to have reactivities consistent with HTLV-II infection. Of these, 67 were from the Kayapo Indian communities, which had an overall seroprevalence rate of greater than 30%. In addition, high seroprevalence rates were observed in three other communities, the Munduruku, Arara do Laranjal and the Tyrio, suggesting that there are additional foci of endemic infection in the Amazon region. In the Kayapo, seroprevalence rates tended to increase with age, supporting the importance of sexual transmission of the virus, and family studies demonstrated that vertical transmission is also an important route of infection. Restriction fragment length polymorphism (RFLP) and nucleotide sequence analysis of a region of the env gene demonstrated that the Kayapo are infected with the HTLV-IIa subtype. Moreover, nucleotide sequence analysis of the LTR demonstrated that this belonged to a distinct HTLV-IIa phylogenetic group. The identification of HTLV-IIa in the Kayapo is, as far as we are aware, the first identified endemic focus of infection by this subtype of HTLV-II in the Americas.

The prevalence of antibodies to Chlamydia was determined in 9 population groups with different risk levels for sexually transmitted diseases in Belém, Pará state, Brazil. 583 serum samples were examined by the indirect immunofluorescence test. The prevalence rates varied from 33.3% in patients attending a sexually transmitted disease clinic to 97.1% in Parakana Indians. One or more pathogens were found in 55 of 86 patients presenting a clinical picture of urethritis; C. trachomatis was isolated from 11% (6/55) of these cases by inoculation to McCoy cell cultures, accounting for 30% (6/20) of the cases of non-gonococcal urethritis. C. trachomatis was isolated from one of 28 female patients (3.6%) attending gynaecology and obstetrics outpatient clinics. The positive patients had no symptom or complaint that would have suggested the diagnosis.

The occurrence of laboratory-acquired infections have elicited in the last ten years an intense interest in methods and procedures for the safe handling of microbiological material. The major laboratory safety problem is aerial transmission, however, protection against airborne hazards is efficiently achieved by the use of microbiological safety cabinets. Biosafety rules should be strictly followed by all members of a laboratory. Evaluation of these procedures should be effectively performed by an independent biosafety committee. The upsurge of AIDS should stimulate the adoption of safe working procedures in the laboratory.