Peptides containing T cell epitopes, derived from Sm14, but not from paramyosin, induce a Th1 type of immune response, reduction in liver pathology and partial protection against Schistosoma mansoni infection in mice

Sm14 and paramyosin are two major Schistosoma mansoni vaccine candidate antigens. Recently, we have identified Sm14 and paramyosin epitopes that are recognized by T cells of resistant individuals living in endemic areas for schistosomiasis. Herein, mice were immunized with these peptides separately or in association in order to evaluate their vaccine potential. Immunization of mice with Sm14 peptides alone or mixed with paramyosin peptides was able to induce 26%-36.7% or 28%-29.2% of worm burden reduction, 67% or 46% of intestinal eggs reduction and also 54%-61% or 43%-52% of liver pathology reduction, respectively. Protection was associated with a Th1 type of immune response induced by Sm14 peptide immunization. In contrast, paramyosin peptide vaccination did not engender protective immunity or liver pathology reduction and immunization was associated with a Th2 type of immune response. (C) 2008 Elsevier B.V. All rights reserved.

B-1 cells temper endotoxemic inflammatory responses

Sepsis syndrome is caused by inappropriate immune activation due to bacteria and bacterial components released during infection. This syndrome is the leading cause of death in intensive care units. Specialized B-lymphocytes located in the peritoneal and pleural cavities are known as B-1 cells. These cells produce IgM and IL-10, both of which are potent regulators of cell-mediated immunity. It has been suggested that B-1 cells modulate the systemic inflammatory response in sepsis. In this study, we conducted in vitro and in vivo experiments in order to investigate a putative role of B-1 cells in a murine model of LPS-induced sepsis. Macrophages and B-1 cells were studied in monocultures and in co-cultures. The B-1 cells produced the anti-inflammatory cytokine IL-10 in response to LPS. In the B-1 cell-macrophage co-cultures, production of proinflammatory mediators (TNF-alpha, IL-6 and nitrite) was lower than in the macrophage monocultures, whereas that of IL-10 was higher in the co-cultures. Co-culture of B-1 IL-10(-/-) cells and macrophages did not reduce the production of the proinflammatory mediators (TNF-alpha, IL-6 and nitrite). After LPS injection, the mortality rate was higher among Balb/Xid mice, which are B-1 cell deficient, than among wild-type mice (65.0% vs. 0.0%). The Balb/Xid mice also presented a proinflammatory profile of TNF-alpha, IL-6 and nitrite, as well as lower levels of IL-10. In the early phase of LPS stimulation, B-1 cells modulate the macrophage inflammatory response, and the main molecular pathway of that modulation is based on IL-10-mediated intracellular signaling. (C) 2010 Elsevier GmbH. All rights reserved.

Lymphocytic prolactin does not contribute to systemic lupus erythematosus hyperprolactinemia

Introduction Lymphocytic prolactin (PRL) gene expression is detected in the majority of the immune cells and it is not known if this source contributes to hyperprolactinemia in systemic lupus erythematosus (SLE). We have therefore evaluated lymphocytic PRL secretion and gene expression in SLE and healthy controls. Methods Thirty SLE patients (ACR criteria) and 10 controls were selected for the study. Serum levels of PRL and macroprolactin were detected by immunofluorometric assay and gel filtration chromatography, respectively. The lymphocytic biological activity was determined by Nb2 cells bioassays. Lymphocytic PRL gene expression was evaluated by RT-PCR assay. Results The median serum PRL levels of the 30 SLE patients was higher than the control group (9.65 (1.9-38.9) vs. 6.40 (2.4-10.3) ng/mL, p=0.03). A significant difference was detected between median serum PRL levels of active SLE, inactive SLE and controls (10.85 (5-38.9) vs. 7.65 (1.9-15.5) vs. 6.40 (2.4-10.3) ng/mL), p=0.01). The higher frequency of mild hyperprolactinemia was detected among active SLE in comparison with inactive SLE and controls (7(38.9%) vs. 1 (8.3%) vs. 0(0%)), with statistical significance (p=0.02). Nb2 cells assay revealed uniformly low levels of lymphocytic PRL in active, inactive and control groups without statistical significance among them (24.2 (8-63) vs. 27 (13.6-82) vs. 29.5 (8-72) ng/mL), p=0.84). Furthermore, median lymphocytic PRL gene expression evaluated by RT-PCR assay was comparable in both active and inactive SLE groups (p=0.12). Conclusion This is the first study to exclude a lymphocytic source of PRL, pointing out a pituitary etiology for hyperprolactinemia in SLE. However, other sources from the immune system cannot be ruled out.

The-2518 bp promoter polymorphism at CCL2/MCP1 influences susceptibility to mucosal but not localized cutaneous leishmaniasis in Brazil

Mucosal leishmaniasis (ML) follows localized cutaneous leishmaniasis (CL) caused by Leishmania braziliensis. Proinflammatory responses mediate CL self-healing but are exaggerated in ML Proinflammatory monocyte chemoattractant protein 1 (MCP-1; encoded by CCL2) is associated with CL We explore its role in CL/ML through analysis of the regulatory CCL2 -2518 bp promoter polymorphism in CL/ML population samples and families from Brazil. Genotype frequencies were compared among ML/CL cases and control groups using logistic regression and the family-based association test (FBAT). MCP-1 was measured in plasma and macrophages. The GG recessive genotype at CCL2 -2518 bp was more common in patients with ML (N = 67) than in neighborhood control (NC; N = 60) subjects (OR 1.78; 95% Cl 1.01-3.14; P = 0.045), than in NC combined with leishmanin skin-test positive (N = 60) controls (OR 4.40; 95% CI 1.42-13.65; P = 0.010), and than in controls combined with CL (N = 60) patients (OR 2.78; 95% CI 1.13-6.85; P = 0.045). No associations were observed for CL compared to any groups. FBAT (91 ML and 223 CL cases in families) confirmed recessive association of ML with allele G (Z = 2.679; P = 0.007). Higher levels of MCP-1 occurred in plasma (P = 0.03) and macrophages (P < 0.0001) from GG compared to AA individuals. These results suggest that high MCP-1 increases risk of ML (C) 2010 Elsevier B.V. All rights reserved.

A prognostic score for AIDS-related diffuse large B-cell lymphoma in Brazil

The aim of this study was to evaluate a prognostic score for aids-related lymphoma (ARL). A retrospective study of 104 patients with ARL treated between January 1999 and December 2007 was conducted. Diffuse large B-cell lymphoma (DLBC) was the most observed histological type (79.8%). The median CD4 lymphocyte count at lymphoma diagnosis was 125 cells per microliter. Treatment response could be evaluated in 83 (79.8%) patients, and 38 (45.8%) reached complete remission (CR); overall response rate was 51.8% (95 CI = 38.5-65.1%). After a median follow-up of 48 months, the 4-year overall survival (OS) rate among all patients was 35.8%, with a median survival time of 9.7 months (95% CI = 5.5-13.9 months). The survival risk factors observed in multivariate analysis (previous AIDS and high-intermediate/high international prognostic index (IPI)) were combined to construct a risk score, which divided the whole patient population in three distinct groups as low, intermediate, and high risk. When this score was applied to DLBC patients, a clear distinction in response rates and in OS could be demonstrated. Median disease-free survival (DFS) for patients that achieved CR was not reached, and DFS in 4 years was 83.0%. Our results show that the reduced OS observed could be explained by poor immune status with advanced stage of disease seen in our population of HIV-positive patients. Further studies will be needed to clarify the role of different treatment approaches for ARL in the setting of marked immunosuppression and to identify a group of patients to whom intensive therapy could be performed with a curative intent.

Molecular characterization of the Hepatitis B virus genotypes in Colombia: A Bayesian inference on the genotype F

Hepatitis B is a worldwide health problem affecting about 2 billion people and more than 350 million are chronic carriers of the virus. Nine HBV genotypes (A to I) have been described. The geographical distribution of HBV genotypes is not completely understood due to the limited number of samples from some parts of the world. One such example is Colombia, in which few studies have described the HBV genotypes. In this study, we characterized HBV genotypes in 143 HBsAg-positive volunteer blood donors from Colombia. A fragment of 1306 bp partially comprising HBsAg and the DNA polymerase coding regions (S/POL) was amplified and sequenced. Bayesian phylogenetic analyses were conducted using the Markov Chain Monte Carlo (MCMC) approach to obtain the maximum clade credibility (MCC) tree using BEAST v.1.5.3. Of all samples, 68 were positive and 52 were successfully sequenced. Genotype F was the most prevalent in this population (77%) - subgenotypes F3 (75%) and Fib (2%). Genotype G (7.7%) and subgenotype A2 (15.3%) were also found. Genotype G sequence analysis suggests distinct introductions of this genotype in the country. Furthermore, we estimated the time of the most recent common ancestor (TMRCA) for each HBV/F subgenotype and also for Colombian F3 sequences using two different datasets: (i) 77 sequences comprising 1306 bp of S/POL region and (ii) 283 sequences comprising 681 bp of S/POL region. We also used two other previously estimated evolutionary rates: (i) 2.60 x 10(-4) s/s/y and (ii) 1.5 x 10(-5) s/s/y. Here we report the HBV genotypes circulating in Colombia and estimated the TMRCA for the four different subgenotypes of genotype F. (C) 2010 Elsevier B.V. All rights reserved.

Phylogenetic Analysis of Hepatitis B Virus Genotype F Complete Genome Sequences From Chilean Patients With Chronic Infection

Molecular epidemiological data concerning the hepatitis B virus (HBV) in Chile are not known completely. Since the HBV genotype F is the most prevalent in the country, the goal of this study was to obtain full HBV genome sequences from patients infected chronically in order to determine their subgenotypes and the occurrence of resistance-associated mutations. Twenty-one serum samples from antiviral drug-naive patients with chronic hepatitis B were subjected to full-length PCR amplification, and both strands of the whole genomes were fully sequenced. Phylogenetic analyses were performed along with reference sequences available from GenBank (n = 290). The sequences were aligned using Clustal X and edited in the SE-AL software. Bayesian phylogenetic analyses were conducted by Markov Chain Monte Carlo simulations (MCMC) for 10 million generations in order to obtain the substitution tree using BEAST. The sequences were also analyzed for the presence of primary drug resistance mutations using CodonCode Aligner Software. The phylogenetic analyses indicated that all sequences were found to be the HBV subgenotype F1b, clustered into four different groups, suggesting that diverse lineages of this subgenotype may be circulating within this population of Chilean patients. J. Med. Virol. 83: 1530-1536, 2011. (C) 2011 Wiley-Liss, Inc.

Hepatitis B virus and hepatitis delta virus genotypes in outbreaks of fulminant hepatitis (Labrea black fever) in the western Brazilian Amazon region

The genotypes of hepatitis B (HBV) and delta (HDV) viruses circulating among fulminant hepatitis cases from the western Amazon Basin of Brazil were characterized in this study. HBV and HDV isolates were obtained from liver samples from 14 patients who developed fulminant hepatitis and died during 1978-1989. HBV DNA and HDV RNA were detected in all samples. Phylogenetic analyses of HDV sequences showed that they all clustered with previously characterized sequences of HDV genotype 3 (HDV-3). HBV genotypes F, A and D were found in 50.0, 28.6 and 21.4% of cases, respectively. These results confirm the predominance of HDV-3 in South America and its association with the severe form of hepatitis, and the finding of the co-infection of HDV-3 with different genotypes of HBV suggests that the association between HDV-3 and HBV-F is not necessarily causally related to a more severe clinical course of infection.

A phylogenetic study of hepatitis B virus in chronically infected Brazilian patients of Western and Asian descent

Hepatitis B virus (HBV) causes one of the most important chronic viral infections worldwide. HBV is classified into eight genotypes whose epidemiology varies geographically. In Brazil, genotypes A, D, and F are more frequent, while in East Asia, genotypes B and C predominate. Several studies showed that immigrants retain the HBV infection pattern of their ancestral country. To identify HBV genotypes infecting chronic carriers in Brazilian families of Western and Asian descent by Hepatitis B surface antigen gene sequencing and analyze the route of viral transmission by phylogenetic analysis of viral sequences. Eighty-seven people chronically infected with HBV were separated into two groups: Western descent (27) and Asian descent (60). Surface and pre-core/core genes were amplified from serum HBV-DNA and sequences were subjected to phylogenetic analysis. HBV genotype A was found in 74% of Western subjects, while genotype C was found in 94% of Asian patients. Thirty-eight percent of Western families were infected with HBV with similar pre-core/core sequences, while only 25% of Asian families showed similarity in these sequences. Phylogenetical analysis of pre-core/core HBV gene suggested intra-familial transmission of HBV in 38% of Western families and 25% of Asian families. Analysis of HBsAg gene sequences helped to define the HBV genotype but did not allow inferring route of transmission as its sequences showed a smaller phylogenetic signal than pre-core/core sequences. Chronic HBV carriers of Asian descent born in or living in Brazil were infected with the same HBV genotype predominant in their ancestral country.

Oral cavity is not a reservoir for Helicobacter pylori in infected patients with functional dyspepsia

Helicobacter pylori infection is very prevalent in Brazil, infecting almost 65% of the population. The aim of this study was to evaluate the presence of this bacterium in the oral cavity of patients with functional dyspepsia (epigastric pain syndrome), establish the main sites of infection in the mouth, and assess the frequency of cagA and vacA genotypes of oral H. pylori. All 43 outpatients with epigastric pain syndrome, who entered the study, were submitted to upper gastrointestinal endoscopy to rule out organic diseases. Helicobacter pylori infection in the stomach was confirmed by a rapid urease test and urea breath tests. Samples of saliva, the tongue dorsum and supragingival dental plaque were collected from the oral cavity of each subject and subgingival dental plaque samples were collected from the patients with periodontitis; H. pylori infection was verified by polymerase chain reaction using primers that amplify the DNA sequence of a species-specific antigen present in all H. pylori strains; primers that amplify a region of urease gene, and primers for cagA and vacA (m1, m2, s1a, s1b, s2) genotyping. Thirty patients harbored H. pylori in the stomach, but it was not possible to detect H. pylori in any oral samples using P1/P2 and Urease A/B. The genotype cagA was also negative in all samples and vacA genotype could not be characterized (s-m-). The oral cavity may not be a reservoir for H. pylori in patients with epigastric pain syndrome, the bacterium being detected exclusively in the stomach.

Hepatitis D and B virus genotypes in chronically infected patients from the Eastern Amazon Basin

Hepatitis D virus (HDV) is a defective hepatotropic virus whose infectivity is dependent on hepatitis B virus (HBV). HDV super- or co-infiection leads to an increased risk of fulminant hepatitis or progression to severe chronic liver disease in HBV infected patients. The Brazilian Amazon Basin has been reported to be endemic for HBV and HDV, especially in the Western Amazon Basin. In this region, HDV infection is frequently associated with acute fulminant hepatitis with characteristic histologic features. HDV is classified into seven major clades (HDV-1 to HDV-7) and HBV is subdivided into eight genotypes (A-H). HDV and HBV genotypes have been shown to have a distinct geographic distribution. The aim of this study was to determine the HBV and HDV genotypes harbored by chronically infected patients from the Eastern Amazon Basin, Brazil. We studied 17 serum samples from HBV and HDV chronically infected patients admitted to a large public hospital (Santa Casa de Misericordia) at Belem, state of Para, Brazil, between 1994 and 2002. HDV-3 and HBV genotype A (subtype adw2) have been identified in all cases, in contrast to previous studies from other regions of the Amazon, where HBV genotype F has been found co-infecting patients that harbored HDV-3. The HDV-3/HBV-A co-infection suggests that there is not a specific interaction between HBV and HDV genotypes, and co-infection might merely reflect the most frequent genotypes found in a particular geographic area. The analysis of the carboxy-terminal region of the large hepatitis D antigen (L-HDAg), which interacts with the hepatitis B surface antigen (HBsAg) and is essential for HDV assembly, showed some diversity between the different isolates from the Eastern Amazon. This diversity is not observed among HDV-3 sequences from other South American regions. (C) 2008 Elsevier B.V. All rights reserved.

Progesterone, estrogen and pregnancy do not decrease colon myoelectric activity in rats: An in vivo study

Background: Progesterone, estrogen and the hormonal complex of pregnancy have been responsible for some degree of colon hypomotility in human pregnancy. Objective: To find out if estrogen, progesterone and the hormonal complex of pregnancy decrease colon myoelectric activity. Methods: The study was performed in 37 healthy female rats in which electrodes were implanted on the serosa of the proximal ascendent, distal ascendent, transverse, and descendent colon. We analyzed the records of colon myoelectric activity in vivo in five groups: control, ovariectomized, ovariectomized and treated with estrogen, ovariectomized and treated with progesterone, and pregnant rats. Results: We found a great variation in myoelectric activity in all groups studied. The mean of electric activity did not show statistical difference among the five groups, but pregnant rats had a statistically significant higher duration of maximum electric activity in all distances from the cecocolon junction. Conclusion: Pregnant rats had a statistically higher duration of maximum electric activity. If we could transpose these results to humans, this increase in duration of colon myoelectric activity could explain, in part, the slight constipation that some pregnant women have. Copyright (C) 2008 S. Karger AG, Basel.

The GHEP-EMPOP collaboration on mtDNA population data-A new resource for forensic casework

Mitochondrial DNA (mtDNA) population data for forensic purposes are still scarce for some populations, which may limit the evaluation of forensic evidence especially when the rarity of a haplotype needs to be determined in a database search. In order to improve the collection of mtDNA lineages from the Iberian and South American subcontinents, we here report the results of a collaborative study involving nine laboratories from the Spanish and Portuguese Speaking Working Group of the International Society for Forensic Genetics (GHEP-ISFG) and EMPOP. The individual laboratories contributed population data that were generated throughout the past 10 years, but in the majority of cases have not been made available to the scientific community. A total of 1019 haplotypes from Iberia (Basque Country, 2 general Spanish populations, 2 North and 1 Central Portugal populations), and Latin America (3 populations from Sao Paulo) were collected, reviewed and harmonized according to defined EMPOP criteria. The majority of data ambiguities that were found during the reviewing process (41 in total) were transcription errors confirming that the documentation process is still the most error-prone stage in reporting mtDNA population data, especially when performed manually. This GHEP-EMPOP collaboration has significantly improved the quality of the individual mtDNA datasets and adds mtDNA population data as valuable resource to the EMPOP database (www.empop.org). (C) 2010 Elsevier Ireland Ltd. All rights reserved.

Distinct resistance mutation and polymorphism acquisition in HIV-1 protease of subtypes B and F1 from children and adult patients under virological failure

The goal of this work was to compare the differences between human immunodeficiency Virus type 1 (HIV-1) of B and F1 Subtypes in the acquisition of major and rninot- protease inhibitor (P1)-associated resistance mutations and of other polymorphisms at the protease (PR) gene, through a cross sectional Study. PR sequences from subtypes B and F1 isolates matched according to P1 exposure time from Brazilian patients were included in this study. Sequences were separated in four groups: 24 and 90 from children and 141 and 99 from adults infected with isolates of subtypes F1 and B, respectively. For comparison, 211 subype B and 79 subtype F1 PR sequences from drug-naive individuals Were included. Demographic and clinical data were similar among B- and F1-infected patients. In untreated patients, Mutations L1OV, K20R, and M361 were more frequent in subtype F1, while L63P, A7IT, and V771 were more prevalent in Subtype B. In treated patients, K20M, D30N, G73S, 184V, and L90M, were More prevalent in subtype B, and K20T and N88S Were more prevalent in Subtype F1. A higher proportion of subtype F1 than Of subtype B Strains Containing other polymorphisms was observed. V82L mutation was Present With increased frequency in isolates from children compared to isolates from adults infected with both subtypes. We could observe a faster resistance emergence in children than in adults, during treatment with protease inhibitors. This data provided evidence that, although rates of overall drug resistance do not differ between subtypes B and F1, the former accumulates resistance at higher proportion in specific amino acid positions of protease when compared to the latter. (c) 2008 Elsevier B.V. All rights reserved.

Methylprednisolone improves lung mechanics and reduces the inflammatory response in pulmonary but not in extrapulmonary mild acute lung injury in mice

Objective: Gorticosteroids have been proposed to be effective in modulating the inflammatory response and pulmonary tissue remodeling in acute lung injury (ALI). We hypothesized that steroid treatment might act differently in models of pulmonary (p) or extrapulmonary (exp) ALI with similar mechanical compromise. Design: Prospective, randomized, controlled experimental study. Setting: University research laboratory. Subjects: One hundred twenty-eight BALB/c mice (20-25 g). Interventions: Mice were divided into six groups. In control animals sterile saline solution was intratracheally (0.05 mL, Cp) or intraperitoneally (0.5 mL, Gexp) injected, whereas ALI animals received Escherichia coli lipopolysaccharide intratracheally (10 mu g, ALIp) or intraperitoneally (125 mu g, ALIexp). Six hours after lipopolysaccharide administration, ALIp and ALlexp animals were further randomized into subgroups receiving saline (0.1 mL intravenously) or methylprednisolone (2 mg/kg intravenously, Mp and Mexp, respectively). Measurements and Main Results: At 24 hrs, lung state elastance, resistive and viscoelastic pressures, lung morphometry, and collagen fiber content were similar in both ALI groups. KC, interieukin-6, and transforming growth factor (TGF)-beta levels in bronchoatveolar lavage fluid, as well as tumor necrosis factor (TNF)-alpha, migration inhibitory factor (MIF), interferon (IFN)-gamma, TGF-beta 1 and TGF-beta 2 messenger RNA expression in lung tissue were higher in ALIp than in ALIexp animals. Methylprednisolone attenuated mechanical and morphometric changes, cytokine levels, and TNF-alpha, MIF, IFN gamma, and TGF-beta 2 messenger RNA expression only in ALIp animals, but prevented any changes in collagen fiber content in both ALI groups. Conclusions. Methylprednisolone is effective to inhibit fibrogenesis independent of the etiology of ALI, but its ability to attenuate inflammatory responses and lung mechanical changes varies according to the cause of ALI.