Galectin-1 exerts inhibitory effects during DENV-1 infection

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Fluorescent antibody test, quantitative polymerase chain reaction pattern and clinical aspects of rabies virus strains isolated from main reservoirs in Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Evaluation of short-interfering RNAs treatment in experimental rabies due to wild-type virus

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Assessment of health-related quality of life and related factors in patients with chronic liver disease

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Seroprevalence of equine influenza virus in northeast and southern Mexico

EQUINE influenza A virus (EIV) is a highly infectious respiratory pathogen of horses (Hannant and Mumford 1996, Palese and Shaw 2007). The illness is characterized by an abrupt onset of fever, depression, coughing and nasal discharge, and is often complicated by secondary bacterial infections that can lead to pneumonia and death. Two subtypes of EIV, H3N8 and H7N7, have been isolated. The H7N7 subtype was first isolated from a horse in Czechoslovakia in 1956 (Prague/56), and the H3N8 subtype was first isolated from a horse in Miami in 1963 (Sovinova and others 1958, Waddell and others 1963). The last confirmed outbreak of H7N7 occurred in 1979, and this subtype is now considered to be either extinct or circulating at low levels in a few geographical areas (Ismail and others 1990, Webster 1993, Singh 1994, Madic and others 1996, van Maanen and Cullinane 2002). The H3N8 subtype is a common cause of disease in horses worldwide, particularly in areas where vaccination is not routinely performed (Paillot and others 2006).

Seeking a Second Opinion: Uncertainty in Disease Ecology

Analytical methods accounting for imperfect detection are often used to facilitate reliable inference in population and community ecology. We contend that similar approaches are needed in disease ecology because these complicated systems are inherently difficult to observe without error. For example, wildlife disease studies often designate individuals, populations, or spatial units to states (e.g., susceptible, infected, post-infected), but the uncertainty associated with these state assignments remains largely ignored or unaccounted for. We demonstrate how recent developments incorporating observation error through repeated sampling extend quite naturally to hierarchical spatial models of disease effects, prevalence, and dynamics in natural systems. A highly pathogenic strain of avian influenza virus in migratory waterfowl and a pathogenic fungus recently implicated in the global loss of amphibian biodiversity are used as motivating examples. Both show that relatively simple modifications to study designs can greatly improve our understanding of complex spatio-temporal disease dynamics by rigorously accounting for uncertainty at each level of the hierarchy.

A Silent Enzootic of an Orthopoxvirus in Ghana, West Africa: Evidence for Multi-Species Involvement in the Absence of Widespread Human Disease

Human monkeypox has never been reported in Ghana, but rodents captured in forested areas of southern Ghana were the source of the monkeypox virus introduced into the United States in 2003. Subsequent to the outbreak in the United States, 204 animals were collected from two commercial trapping sites in Ghana. Animal tissues were examined for the presence of orthopoxvirus (OPXV) DNA using a real-time polymerase chain reaction, and sera were assayed for antibodies against OPXV. Animals from five genera (Cricetomys , Graphiurus , Funiscirus, and Heliosciurus ) had antibodies against OPXV, and three genera (Cricetomys , Graphiurus , and Xerus) had evidence of OPXV DNA in tissues. Additionally, 172 persons living near the trapping sites were interviewed regarding risk factors for OPXV exposure, and their sera were analyzed. Fifty-three percent had IgG against OPXV; none had IgM. Our findings suggest that several species of forest-dwelling rodents from Ghana are susceptible to naturally occurring OPXV infection, and that persons living near forests may have low-level or indirect exposure to OPXV-infected animals, possibly resulting in sub-clinical infections.

QUANTITATIVE TRAIT LOCI FOR AGRONOMIC AND END-USE QUALITY PERFORMANCE AND THE EFFECT OF SOILBORNE WHEAT MOSAIC VIRUS IN A HARD WINTER WHEAT POPULATION IN NEBRASKA

To better understand agronomic and end-use quality in wheat (Triticum aestivum L.) we developed a population containing 154 F6:8 recombinant inbred lines (RILs) from the cross TAM107-R7/Arlin. The parental lines and RILs were phenotyped at six environments in Nebraska and differed for resistance to Wheat soilborne mosaic virus (WSBMV), morphological, agronomic, and end-use quality traits. Additionally, a 2300 cM genome-wide linkage map was created for quantitative trait loci (QTL) analysis. Based on our results across multiple environments, the best RILs could be used for cultivar improvement. The population and marker data are publicly available for interested researchers for future research. The population was used to determine the effect of WSBMV on agronomic and end-use quality and for the mapping of a resistance locus. Results from two infected environments showed that all but two agronomic traits were significantly affected by the disease. Specifically, the disease reduced grain yield by 30% of susceptible RILs and they flowered 5 d later and were 11 cm shorter. End-use quality traits were not negatively affected but flour protein content was increased in susceptible RILs. The resistance locus SbmTmr1 mapped to 27.1 cM near marker wPt-5870 on chromosome 5DL using ELISA data. Finally, we investigated how WSBMV affected QTL detection in the population. QTLs were mapped at two WSBMV infected environments, four uninfected environments, and in the resistant and susceptible RIL subpopulations in the infected environments. Fifty-two significant (LOD≥3) QTLs were mapped in RILs at uninfected environments. Many of the QTLs were pleiotropic or closely linked at 6 chromosomal regions. Forty-seven QTLs were mapped in RILs at WSBMV infected environments. Comparisons between uninfected and infected environments identified 20 common QTLs and 21 environmentally specific QTLs. Finally, 24 QTLs were determined to be affected by WSBMV by comparing the subpopulations in QTL analyses within the same environment. The comparisons were statistically validated using marker by disease interactions. These results showed that QTLs can be affected by WSBMV and careful interpretation of QTL results is needed where biotic stresses are present. Finally, beneficial QTLs not affected by WSBMV or the environment are candidates for marker-assisted selection.

Assessment of Texas Medical Providers Concerning Rabies Vaccines

Rabies is an important zoonotic disease in Texas and thousands of people each year either request or require rabies prophylaxis because they have ‘high risk’ jobs or are exposed to the disease. After experiencing difficulty in receiving rabies prophylaxis from physicians, we conducted a survey of Texas medical providers to assess their knowledge of rabies vaccine procedures and their experience with rabies vaccines. Most providers in Texas (>95% of 297) rarely saw patients for rabies prophylaxis; therefore, providers have minimal, if any, experience with the procedures of acquiring and administering the vaccine. Providers varied greatly in their responses to our questions of where to acquire the vaccine, how and where to administer the vaccine, and where to acquire information about the vaccine. State and local health departments should target medical clinics and physician associations as outlets to disseminate information regarding rabies, rabies prophylaxis, and treatment.

INFLUENCE OF TYPE 2 BOVINE VIRAL DIARRHEA VIRUS NPRO ON ENHANCEMENT OF BOVINE RESPIRATORY SYNCYTIAL VIRUS REPLICATION MEDIATED BY ANTAGONISM OF HOST CELL INTERFERON TYPE I RESPONSES

Bovine viral diarrhea virus (BVDV) is a member of the genus Pestivirus, Family Flaviviridae. The virus can infect many species of animals of the order Artiodactyla. The BVDV genome encodes an auto protease, Npro, that degrades interferon regulatory factor-3 (IRF-3) reducing type I interferon (IFN-I) production from host cells. Bovine respiratory syncytial virus (BRSV) is a member of the genus Pneumovirus, Family Paramyxoviridae. Concurrent infection with BVDV and BRSV causes more severe respiratory and enteric disease than infection with either virus alone. Our hypothesis was that Npro modulates the innate immune responses to BVDV infection and enhances replication of BVDV or BRSV co-infection. The noncytopathic BVDV2 viruses NY93/c N- Npro 18 EGFP (a mutant with modified Npro fused with enhanced green fluorescent protein), NY93 infectious clone (NY93/c), wild-type NY93-BVDV2 (NY93-wt), and BRSV were evaluated in this study. The objectives of this study were: (1) to characterize the replication kinetics and IFN-I induction in Madin-Darby bovine kidney (MDBK) cells following infection with each of the BVDV isolates, and (2) to characterize the influence of BVDV-mediated IFN-I antagonism on enhancement of BRSV replication in bovine turbinate (BT) cells. NY93/c N- Npro 18 EGFP replicated 0.4 – 1.6 TCID50 logs lower than NY93-wt in MDBK cells. NY93/c N- Npro 18 EGFP-infected MDBK cells synthesized IFN-I significantly higher than NY93/c- and NY93-wt-infected MDBK cells. BT cells co-infected with NY93/c N- Npro 18 EGFP/BRSV or NY93-wt/BRSV were evaluated to determine the effects of co-infection on BRSV replication and IFN-I induction in BT cells. BRSV RNA levels in NY93-wt/BRSV co-infected BT cells were 2.49, 2.79, and 2.89 copy number logs significantly greater than in NY93/c N- Npro 18 EGFP/BRSV co-infected BT cells on days 5, 7, and 9 post-infection, respectively. BVDV RNA levels in NY93/c N- Npro 18 EGFP-infected BT cells were 1.64 – 4.38 copy number logs lower than in NY93-wt-infected BT cells. NY93/c N- Npro 18 EGFP single and co-infected BT cells synthesized IFN-I significantly higher than NY93-wt single and co-infected BT cells. In summary, these findings suggest: (1) NY93/c N- Npro 18 EGFP BVDV2 induced higher levels of IFN-I than BVDV2-wt and may be useful as a safer, replicating BVDV vaccine, and (2) Enhancement of BRSV infection by BVDV co-infection is mediated by antagonism of IFN-I.

Detection of dengue virus in sera of Brazilian blood donors

BACKGROUND: Dengue is the most important arboviral disease in the world. Dengue viruses (DENVs) have produced huge outbreaks in Brazil in the past 25 years with more than 5 million reported cases. During these epidemics, asymptomatic individuals infected with DENV could donate blood and serve as a source of virus dissemination in the community. Here, we studied the circulation of DENV in healthy individuals during an epidemic outbreak. STUDY DESIGN AND METHODS: The study included 500 serum samples from healthy blood donors collected at the Hemotherapy Center of Ribeirao Preto, Brazil, during a dengue outbreak. The presence of DENV RNA in the serum samples was screened by real-time reverse transcriptionpolymerase chain reaction (PCR). The virus serotype was determined by a heminested PCR procedure. A partial fragment of the NS5 gene sequence was used for phylogenetic analysis. RESULTS: DENV RNA was detected in the serum sample of 2 of 500 (0.4%) individuals. Both of them were infected with DENV-3 Genotype III, a virus that has been circulating in Brazil in the past decade. CONCLUSION: Individuals with asymptomatic DENV infection can be blood donors and serve as a source of virus dissemination in the community. Further studies are needed to determine the risk of recipient infection by DENV as a result of transfusion in Brazil, especially during epidemic periods.

Experimental infection of suckling mice by subcutaneous inoculation with Oropouche virus

Oropouche virus, of the family Bunyaviridae, genus Orthobunyavirus, serogroup Simbu, is an important causative agent of arboviral febrile illness in Brazil. An estimated 500,000 cases of Oropouche fever have occurred in Brazil in the last 30 years, with recorded cases also in Panama, Peru, Suriname and Trinidad. We have developed an experimental model of Oropouche virus infection in neonatal BALB/c mouse by subcutaneous inoculation. The vast majority of infected animals developed disease on the 5th day post infection, characterized mainly by lethargy and paralysis, progressing to death within 10 days. Viral replication was documented in brain cells by in situ hybridization, immunohistochemistry and virus titration. Multi-step immunohistochemistry indicated neurons as the main target cells of OROV infection. Histopathology revealed glial reaction and astrocyte activation in the brain and spinal cord, with neuronal apoptosis. Spleen hyperplasia and mild meningitis were also found, without viable virus detected in liver and spleen. This is the first report of an experimental mouse model of OROV infection, with severe involvement of the central nervous system, and should become useful in pathogenesis studies, as well as in preclinical testing of therapeutic interventions for this emerging pathogen. (c) 2012 Elsevier B.V. All rights reserved.

HIV-1 induces NALP3-inflammasome expression and interleukin-1 beta secretion in dendritic cells from healthy individuals but not from HIV-positive patients

Objective: NALP3-inflammasome is an innate mechanism, alternative to type-1 interferon, which is able to recognize nucleic acids and viruses in the cytoplasm and to induce pro-inflammatory response. Here, we hypothesized the involvement of inflammasome in the early defense against HIV-1 and in the full maturation of dendritic cells: for this, we evaluated the response of dendritic cells pulsed with HIV-1 in terms of inflammasome activation in healthy donors. Moreover, inflammasome response to HIV was evaluated in HIV-infected individuals. Design and methods: Monocyte-derived dendritic cells isolated from 20 healthy individuals (HC-DC) and 20 HIV-1-infected patients (HIV-DC) were pulsed with alditrithiol-2-inactivated HIV-1. We then analyzed inflammasome genes expression and interleukin-1 beta (IL-1 beta) secretion. Results: In HC-DC, HIV-1 induced higher NLRP3/NALP3 mRNA expression compared with other inflammasome genes such as NALP1/NLRP1 or IPAF/NLRC4 (P < 0.001). This augmented expression was accompanied by CASP1-increased and IL1B-increased mRNA levels and by a significant increment of IL-1b secretion (P < 0.05). Otherwise, HIV-1 failed to activate inflammasome and cytokine production in HIV-DC. HIV-DC showed an increased NLRP3/NALP3 basal expression, suggesting a chronic inflammatory profile of patients' immune cells. Conclusion: HIV-1 was able to induce a NALP3-inflammasome response in healthy individuals, indicating that this inflammasome could play a role in the first steps of HIV-1 infection; the consequent inflammatory process may be important for directing host immune response against the virus and/or disease progression. HIV-DC seemed to be chronically activated, but unresponsive against pathogens. Our findings could be of interest considering the ongoing research about dendritic cell manipulation and therapeutic strategies for AIDS involving dendritic cell-based immune-vaccines. (C) 2011 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins

Assessment of tuberculosis treatment accessibility for patients co-infected or not with the human immunodeficiency virus

This study aimed to evaluate accessibility to treatment for people with TB co-infected or not with HIV. This cross-sectional study addressed issues regarding accessibility to treatment in a city in the interior of Sao Paulo state, Brazil. The instrument Primary Care Assessment Tool was utilized with 95 people. To evaluate access to treatment, Student's t test was used. The mean scores of variables were analyzed separately and compared between two groups (people with TB co-infected with HIV and people with TB not co-infected with HIV). Mean scores showed that HIV co-infected people presented greater difficulties in gaining access than those not co-infected. Professionals visited co-infected people more often when compared to those not co-infected; the co-infected people almost never accessed treatment for their disease in the Health Unit nearest their home. There is, therefore, the need for greater integration and communication between the programs for treatment of Tuberculosis and STD/AIDS.

Detection of human T-cell lymphotropic virus type 1 in plasma samples

Human T-cell lymphotropic virus type 1 (HTLV-1) is-an RNA virus responsible for diseases such as HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and adult T-cell leukemia/lymphoma (ATL). Cell-to-cell contact and Tax-induced clonal expansion of infected cells are the main modes of virus replication, making virus detection during the viremic stage difficult. Consequently, the proviral load is the current virologic marker for disease monitoring, but the mechanisms of progression have not been established yet. Thus, this study investigated the presence of virus in plasma from asymptomatic HTLV-1 carriers and from HAM/TSP patients. Real-time PCR was performed on DNA from 150 plasma samples; 12(8%) had detectable DNA amplification, including 6(4%) asymptomatic HTLV-1 carriers and 14(26%) HAM/TSP patients (p < 0.005). Of the 33 samples submitted for nested PCR, six (18%, p = 0.02) were positive for HTLV-1 RNA in the plasma. Additionally, 26 plasma samples were treated with DNAse enzyme to eliminate any DNA contamination before RNA extraction. Two of them (8%) showed amplification for HTLV-1 (p = 0.5). Therefore, this study described for the first time the detection of free HTLV-1 RNA in plasma from HTLV-1-infected subjects, regardless of their clinical status. Thus, HTLV-1 viral replication does occur in plasma, and other transmission pathways for HTLV-1 should be investigated further. (C) 2011 Elsevier B.V. All rights reserved.