Dirce Bonfim de Lima

Two lineages of dengue virus type 2, Brazil.

To the Editor: Dengue viruses (DENVs) belong to the genus Flavivirus (family Flaviviridae) and exist as 4 antigenic types, serotypes 1–4, each with well-defined genotypes. Dengue virus is associated with clinical manifestations that range from asymptomatic infections and relatively mild disease (classic dengue fever) to more severe forms of dengue hemorrhagic fever and dengue shock syndrome. Dengue has become one of the most serious vector-borne diseases in humans. The World Health Organization estimates that 2.5 billion persons live in dengue-endemic areas and >50 million are infected annually (1). In 1986, dengue virus type 1 (DENV-1) caused an outbreak in the state of Rio de Janeiro and has since become a public health concern and threat in Brazil. (2). In 1990, DENV-2 was reported in the state of Rio de Janeiro, where the first severe forms of dengue hemorrhagic fever and fatal cases of dengue shock syndrome were documented. The disease gradually spread to other regions of the country (3). In 2002, DENV-3 caused the most severe dengue outbreak in the country and sporadic outbreaks continued to be documented through 2005 (4). Since 1990, two additional epidemics caused by DENV-2 have occurred (1998 and 2007–2008) in Brazil. A severe DENV-2 epidemic in the state of Rio de Janeiro began in 2007 and continued in 2008; a total of 255,818 cases and 252 deaths were reported (5). This epidemic prompted us to investigate the genetic relatedness of DENV-2 for all of these epidemics. DENV-2 isolates from these epidemic periods were subjected to sequencing and comparison. Gross sequences of DENV-2 isolates from all epidemic periods grouped with sequences from DENV-2 American/Asian genotype; this finding was expected because this genotype is circulating in the Americas (6,7). Sequences of DENV-2 isolates from the 1998 epidemic grouped with sequences of DENV-2 isolates from the 1990 epidemic (data not shown) suggesting that viruses circulating during these 2 epidemic periods belong to the same lineage of the DENV-2 strain originally found in the state of Rio de Janeiro. However, sequences of DENV-2 isolates from 2007/2008 epidemics grouped separately and distinctly from the 1990 and 1998 DENV-2 isolates and represented a monophyletic group in the phylogenetic tree with bootstraps of 98% (Figure). This result shows a temporal circulation of genetically different viruses in Rio de Janeiro that could be a result of local evolution of DENV-2 since its introduction in 1990, or even an introduction of a new lineage of DENV-2 in the region. Figure Neighbor-joining phylogenetic tree of 68 complete envelope (E) gene sequences of dengue virus type 2 (DENV-2). Only bootstrap values >80% are shown. DENV-2 sequences obtained from 21 patients infected during the 1990, 1998, and 2007–2008 ... A study conducted by Aquino et al. (7) showed that Paraguayan DENV-2 strains could be grouped as 2 distinct variants within the American/Asian genotype, thus further supporting that the introduction of new DENV-2 variants may likely associate with the shift of dominant serotypes from DENV-3 to DENV-2 in 2005 and might have caused an outbreak of DENV-2. Our results are consistent with this scenario because was a shift of a dominant serotype from DENV-3 to DENV-2 that was observed in 2008 in Rio de Janeiro. However, other factors, such as immunity level to DENV-3 and DENV-2, could explain the shift of dominant serotype besides the circulation of a new viral variant. Because the dengue outbreaks of 2007 and 2008 were the most severe of the dengue infections in Brazil in terms of number of cases and deaths, this genetically distinct DENV-2 could have contributed to this pathogenic profile. Additionally, these samples came from disperse locations in Rio de Janeiro and we do not believe that there is a clustering issue in our sampling. However, again, other factors must be considered as contributors to this scenario because of the intrinsic properties of this distinct virus, host susceptibility, and secondary cases of infection. In addition, detailed examination of amino acid sequences of Brazilian DENV-2 strains isolated in 1998 and 2008 showed 6 aa substitutions in the envelope gene: V129I, L131Q, I170T, E203D, M340T, and I380V. Our results support the notion that aa positions at 129 and 131 in the envelope gene are critical genetic markers for phylogenetic classification of DENV-2 (7–9). Notably, residue 131 in the envelope gene is located within a pH-dependent hinge region at the interface between domains I and II of the envelope protein. Mutations at this region may affect the pH threshold of fusion and the process of conformational changes (10). Our results suggest the circulation of genetically different DENV-2 in Brazil and that these viruses may have a role in severity of dengue diseases. These findings can help to further understand the complex dynamic pathogenic profile of dengue viruses and their circulation in dengue-endemic regions.

Efeito do exercício físico na percepção de satisfação de vida e função imunológica em pacientes infectados pelo HIV: Ensaio clínico não randomizado

BACKGROUND: There is a lack of research about the relationship between exercise and the psychological well-being of HIV-infected (Human Immunodeficiency Virus) patients. OBJECTIVE: The objective of this study was to investigate the influence of a physical training program on life satisfaction and on the immunological function in HIV-patients. METHODS: A total of 29 HIV-seropositive patients [age: 45±2 yrs; Body Mass Index (BMI): 22.8±1.0 kg/m2 ; TCD4: 20.5±2.0%] were allocated to the control (CG, n=10) and to the experimental groups (EG, n=19). The EG participated in an exercise program combining aerobic, strength, and flexibility exercises for a period of 12 weeks [3 times/week of 30 min of aerobic exercise (workload corresponding to 150 bpm-PWC150); 50 min of strength exercises (3 sets of 12 repetitions in 5 exercises at 60-80% 12 RM); and 10 min of flexibility exercises (2 sets of 30 seconds at maximal range of motion of 8 exercises)]. The immunological function was assessed by flow citometry [absolute and relative TCD4 cells counting] and the life satisfaction was assessed by the Life Satisfaction Index (LSI). RESULTS: The analysis of variance (ANOVA) showed no significant differences for relative and absolute CD4 T counts for both groups, however, a slight enhancement trend in the EG [16%, p=0.19] was observed. There was a significant improvement of LSI [approximately 15%; P<0.05] in EG, but not for CG. CONCLUSION: A physical activity program of moderate intensity improved life satisfaction perception in HIV-infected patients with no immunological function impairment.

Clinical and diagnostic aspects of intestinal microsporidiosis in HIV-infected patients with chronic diarrhea in Rio de Janeiro, Brazil

The objectives of this study were to determine both the prevalence of microsporidial intestinal infection and the clinical outcome of the disease in a cohort of 40 HIV-infected patients presenting with chronic diarrhea in Rio de Janeiro, Brazil. Each patient, after clinical evaluation, had stools and intestinal fragments examined for viral, bacterial and parasitic pathogens. Microsporidia were found in 11 patients (27.5%) either in stools or in duodenal or ileal biopsies. Microsporidial spores were found more frequently in stools than in biopsy fragments. Samples examined using transmission electron microscopy (n=3) or polymerase chain reaction (n=6) confirmed Enterocytozoon bieneusi as the causative agent. Microsporidia were the only potential enteric pathogens found in 5 of the 11 patients. Other pathogens were also detected in the intestinal tract of 21 patients, but diarrhea remained unexplained in 8. We concluded that microsporidial infection is frequently found in HIV infected persons in Rio de Janeiro, and it seems to be a marker of advanced stage of AIDS.

Dislipidemia em pacientes HIV/AIDS em uso de anti-retrovirais num hospital universitário, Rio de Janeiro, Brasil

BACKGROUND: The continuous use of antiretroviral therapy (ART) is associated with several metabolic disturbances. OBJECTIVES: The main objective of this study was to determine the prevalence of dyslipidemia in human immunodeficiency virus/acquired immunological deficiency syndrome (HIV/AIDS) patients followed in the infectious diseases outpatient clinic of Hospital Universitario Pedro Ernesto, of Universidade do Estado do Rio de Janeiro (HUPE/UERJ). MATERIAL AND METHODS: From 10/1/2004 to 5/30/2005, the participants of this study answered a survey about demographic and health data. Afterwards, the following measurements were checked: weight, height, waist and hips. Blood samples were collected for total cholesterol, high-density lipoprotein cholesterol (HDL-C) and triglycerides tests. Out of 268 patients who came to the appointment during the study period, 23 did not attend the blood collection, and 10 did not want to participate. Poisson regression model was used to find the variables associated with dyslipidemia. RESULTS: Out of the 235 patients included in the study 182 (77.5%) had dyslipidemia, with prevalence of male (69.8%) over female ones (30.2%). Among the patients with dyslipidemia, 26.9% had family history of dyslipidemia against 15.1% who did not. Regarding ART duration, both mean and media were higher in the group of patients with dyslipidemia. CONCLUSION: In our study the prevalence of dyslipidemia in HIV/AIDS patients was high (77.5%), and the associated factors were male sex, family history of dyslipidemia and ART duration.

Association of hepatitis C virus NS5B variants with resistance to new antiviral drugs among untreated patients

Mutations located in the 109-amino acid fragment of NS5B are typically associated with resistance to interferon (IFN) and ribavirin (RIB) and to new antiviral drugs. The prevalence of these mutations was examined in 69 drug-naïve individuals with hepatitis C virus (HCV) infections in Rio de Janeiro, Brazil. Mutations related to non-response to IFN/RIB were observed in all subtypes studied (1a, 1b, 2b, 3a and 4). The most common mutation was Q309R, present in all subtypes, except subtype 2b with frequency above 20%. D244N was detected only in subtype 3a and A333E was detected only in subtype 2b. We did not detect the S282T, S326G or T329I mutations in any of the samples analysed. Of note, the C316N mutation, previously related to a new non-nucleoside compound (HCV796 and AG-021541), was observed in only eight of 33 (24%) samples from subtype 1b. Site 316 was under positive selection in this HCV variant. Our data highlight the presence of previously described resistance mutations in HCV genotypes from drug-naïve patients.

High IL-10 production by aged AIDS patients is related to high frequency of Tr-1 phenotype and low in vitro viral replication

This work aims to elucidate the effects of age and HIV-1 infection on the frequency and function of T cell subsets in response to HIV-specific and non-specific stimuli. As compared with the younger AIDS group, the frequencies of naive and central memory T cells were significantly lower in aged AIDS patients. Although there was also a dramatic loss of classical CD4(+)FoxP3(+)CD25(+)Treg cells in this patient group, high frequencies of IL-10-producing CD4(+)FoxP3(-) T cells were observed. In our system, the increased production of IL-10 in aged AIDS patients was mainly derived from Env-specific CD4(+)FoxP3(-)CD152(+) T cells. Interestingly, while the blockade of IL-10 activity by monoclonal antibody clearly enhanced the release of IL-6 and IL-1β by Env-stimulated PBMC cultures from aged AIDS patients, this monoclonal antibody enhanced in vitro HIV-1-replication. In conclusion, HIV infection and aging undoubtedly contribute synergistically to a complex immune dysfunction in T cell compartment of HAART-treated older HIV-infected individuals.

A 3-year follow-up of a brazilian AIDS patient with protracted diarrhea caused by Enterocytozoon bieneusi

Enterocytozoon bieneusi is the most prevalent microsporidian parasite that causes gastrointestinal infection in persons with AIDS. Microsporidia are increasingly recognized as important opportunistic pathogens all over the world but in Brazil only few cases have been reported due either to the non awareness of the clinical presentation of the disease or to difficulties in the laboratory diagnosis. We report a 3-year follow-up of a Brazilian HIV-positive patient in whom microsporidial spores were detected in stools and were identified as E. bieneusi using electron microscopy and PCR. The patient presented with chronic diarrhea, CD4 T-lymphocytes count below 100/mm3 and microsporidial spores were consistently detected in stools. Albendazole was given to the patient in several occasions with transient relief of the diarrhea, which reappeared as soon as the drug was discontinued. Nevertheless, a diarrhea-free period with weight gain up to 18 Kg occurred when a combination of nucleoside and protease inhibitors was initiated as part of the antiviral treatment.

Assessment of Vascular Function in HIV-Infected Patients

Abstract Purpose: The vascular function in HIV-infected persons under HAART and non-HIV-infected persons was investigated.Method: 18 HIV-positive patients and 23 HIV-negative subjects (14 younger group and 9 older group) were evaluated for microvascular vasodilatation during postocclusive reactive hyperemia (PORH) and during prolonged local thermal hyperemia; overall microvascular flux increase induced by iontophoresis of acetylcholine (ACh) and sodium nitroprusside (SNPDVP); Cutaneous vascular conductance (CVC) responses to ACh were lower in HIV patients compared to both HIV-negative groups (mean [SEM]) (HIV positive: 878.2 [99.5]; older HIV negative: 1129.3 [231.6]; younger HIV negative: 1366.5 [172.6] % baseline). Regarding SNP iontophoresis, HIV-positive and older HIV-negative groups showed lower CVC responses than younger HIV-negative group (HIV positive: 1043.0 [164.6]; older HIV-negative: 980.8 [108.3]; younger HIV-negative: 1757.3 [245.1] % baseline). Vasodilatation induced by thermal hyperemia (HIV positive: 1.63 [0.11]; older HIV negative: 1.48 [0.08]; younger HIV negative: 1.85 [0.27] perfusion units/mm Hg) and PORH (HIV positive: 0.374 [0.025]; older HIV negative: 0.326 [0.025]; younger HIV negative: 0.326 [0.037] PU/mm Hg) were similar between all groups. SIDVP was greater in HIV and older healthy groups than younger healthy group (HIV positive: 9.17 [0.42]; older HIV negative: 8.19 [0.43]; younger HIV negative: 6.42 [0.22] m/s).Conclusion: HIV-infected patients under HAART exhibited slight but nonsignificant lower microvas-cular reactivity to pharmacological stimuli and increased arterial stiffness compared to age-matched HIV-negative subjects. Comparison of both HIV-positive and older HIV-negative groups with younger HIV-negative subjects suggests that age plays a major role in microvascular reactivity regardless the HIV-infection.

Study of Natural Cytotoxicity Receptors in Patients with HIV/AIDS and Cancer: A Cross-Sectional Study

The NCR receptors play a fundamental role in the cytotoxicity mediated by NK cells against tumor cells. In the current study, we investigated possible HIV/AIDS-related changes in the expression of the NCR receptors comparing healthy donors, HIV/AIDS patients, and HIV/AIDS patients with cancer (HIV/AIDSWC). The NCRs were quantified in NK cells (NKdim and NKbright) and T lymphocytes from peripheral blood samples by flow cytometry. We found a significant decrease in the frequency of NK cells expressing NKp46 in HIV/AIDS group (p = 0.0012). There was a decrease in the frequency of NK cells expressing NKp46 in the HIV/AIDSWC group; however, this was not statistically significant. We found a significant decrease in the frequency of NK cells expressing NKp30 in the HIV/AIDS group (p = 0.0144). There was a decrease in the frequency of NK cells expressing NKp30 and in the HIV/AIDSWC group, but this was not statistically significant. There were no changes in the distribution of NK cells and their subtypes in both groups.

Association Between XRCC1 and WRN as Genetic Markers of Stability and Susceptibility to Cancer in Patients with HIV/AIDS and Cancer: a Cross-Sectional Study

Background: HIV-induced immunodeficiency has been implicated as a key factor for risk of cancer. Neoplasia is considered to result from accumulation of damage to the genome. Polymorphisms in repair genes, such as the XRCC1 and WRN, have been associated with susceptibility to development of cancer in patients with HIV/AIDS. The aim of this study was to analyze the frequency of polymorphisms in XRCC1 (Arg399Gln) and WRN (Cys1367Arg) in patients with HIV/AIDS with or without cancer. Materials and Methods: Genotyping for analysis of polymorphisms was carried out by PCR (Polymerase Chain Reaction) and RFLP (Restriction Fragment Length Polymorphism). Results: In the genotypic and allelic analysis, no increased risk of cancer was observed with any genotype or allele of XRCC1 (Arg399Gln) singly (prevalence ratio 2.82; p-value= 0.24). However, with the WRN (Cys1367Arg) gene, the heterozygous genotype and arginine allele were associated with increased risk (prevalence ratio= 25.62; p-value= 0.0001). Correlation analysis showed no association between gender and the risk (male p-value= 0.639 and women p-value> 1); however, a positive association for the increased risk of cancer was shown with XRCC1 (Arg399Arg) wild-type homozygous and WRN (Cys1367Arg) heterozygous (p-value< 0.001), with heterozygous XRCC1 (Arg399Gln) and WRN (Cys1367Arg) (p-value< 0.001), and with variant homozygous XRCC1 (Gln399Gln) and heterozygous WRN (Cys1367Arg) (p-value< 0.001). Conclusions: There is no increased risk of cancer in patients who are HIV/AIDS carriers of the XRCC1 (Arg399Gln) gene singly. However, there is a high risk in patients with HIV/AIDS who have the heterozygous genotype and the arginine allele in the WRN (Cys1367Arg) gene singly. Those with WRN (Cys1367Arg) heterozygote genotype showed a high risk of cancer with all genotypes of the XRCC1 (Arg399Gln) gene.