HEV infection in swine from Eastern Brazilian Amazon: Evidence of co-infection by different subtypes

Hepatitis E virus (HEV) is a fecal-orally transmitted member of the genus Hepevirus that causes acute hepatitis in humans and is widely distributed throughout the world. Pigs have been reported as the main source of genotypes 3 and 4 infection to humans in non-endemic areas. To investigate HEV infection in pigs from different regions of Para state (Eastern Brazilian Amazon), we performed serological and molecular analyses of serum, fecal and liver samples from 151 adult pigs slaughtered between April and October 2010 in slaughterhouses in the metropolitan region of Belem, Para. Among the animals tested, 8.6% (13/151) were positive for anti-HEV IgG but not for anti-HEV IgM. HEV RNA was detected in 4.8% (22/453) of the samples analyzed and 9.9% (15/151) of the animals had at least one positive sample. Phylogenetic analysis showed that all sequences belonged to genotype 3 that were related to human isolates from other non-endemic regions, suggesting that the isolates had zoonotic potential. Subtypes 3c and 3f were simultaneously detected in some pigs, suggesting co-infection by more than one strain and/or the presence of a recombinant virus. These results constitute the first molecular and serologic evidence of swine HEV circulation in the Eastern Brazilian Amazon. (C) 2012 Elsevier Ltd. All rights reserved.

Oxytocin interference in the effects induced by inhalation of 7.5% CO2 in healthy volunteers

Objective The objective of this study was to assess the acute effect of intranasally administered oxytocin (OT) on subjective states, cardiovascular, and endocrine parameters in healthy volunteers who inhaled 7.5% CO2. Methods Forty-five subjects were allocated into three matched groups of subjects who received 24?international units (IU) of OT, 2?mg of lorazepam (LZP), or placebo (PL). The challenge consisted of medical air inhalation for 20?min, 10?min of rest, and CO2 7.5% inhalation for 20?min. Subjective effects were evaluated by self-assessment scales; heart rate, blood pressure, skin conductance, and salivary cortisol were also measured. Assessments were performed at four time points: (i) baseline (-15?min); (ii) post-air inhalation (90?min); (iii) post-CO2 inhalation (120?min), and (iv) post-test (160?min). Results CO2 inhalation significantly increased the anxiety score in the PL group compared with the post-air measurement but not in the OT or LZP groups. The LZP reduced anxiety after medical air inhalation. Other parameters evaluated were not affected by OT. Conclusion OT, as well as LZP, prevented CO2-induced anxiety, suggesting that this hormone has anxiolytic properties. Copyright (C) 2012 John Wiley & Sons, Ltd.

Hematological alterations during experimental canine infection by Trypanosoma cruzi

To confirm that Beagle dogs are a good experimental model for Chagas disease, we evaluated hematological alterations during the acute and chronic phases in Beagle dogs infected with the Y, Berenice-78 (Be-78) and ABC strains of Trypanosoma cruzi, correlating clinical signs with the parasitemia curve. We demonstrate that the acute phase of infection was marked by lethargy and loss of appetite. Simultaneously, we observed anemia, leukocytosis and lymphocytosis. Also,we describe hematological alterations and clinical signs that were positively correlated with the parasitemia during the experimental infection with the three strains of T cruzi, and demonstrate that experimental infection of Beagle is a trustworthy model for Chagas disease.

Recipient of kidney from donor with asymptomatic infection by Paracoccidioides brasiliensis

The increase in solid organ transplantations may soon create a rise in the occurrence of endemic fungal diseases, such as paracoccidioidomycosis, due to the lack of rigorous screening of donors from endemic areas. Here we present the first case of an immunocompetent and asymptomatic kidney donor who had Paracoccidioides brasiliensis infected-adrenal tissue but no glandular dysfunction.

Oxidative Stress and Modification of Renal Vascular Permeability Are Associated with Acute Kidney Injury during P. berghei ANKA Infection

Malaria associated-acute kidney injury (AKI) is associated with 45% of mortality in adult patients hospitalized with severe form of the disease. However, the causes that lead to a framework of malaria-associated AKI are still poorly characterized. Some clinical studies speculate that oxidative stress products, a characteristic of Plasmodium infection, as well as proinflammatory response induced by the parasite are involved in its pathophysiology. Therefore, we aimed to investigate the development of malaria-associated AKI during infection by P. berghei ANKA, with special attention to the role played by the inflammatory response and the involvement of oxidative stress. For that, we took advantage of an experimental model of severe malaria that showed significant changes in the renal pathophysiology to investigate the role of malaria infection in the renal microvascular permeability and tissue injury. Therefore, BALB/c mice were infected with P. berghei ANKA. To assess renal function, creatinine, blood urea nitrogen, and ratio of proteinuria and creatininuria were evaluated. The products of oxidative stress, as well as cytokine profile were quantified in plasma and renal tissue. The change of renal microvascular permeability, tissue hypoxia and cellular apoptosis were also evaluated. Parasite infection resulted in renal dysfunction. Furthermore, we observed increased expression of adhesion molecule, proinflammatory cytokines and products of oxidative stress, associated with a decrease mRNA expression of HO-1 in kidney tissue of infected mice. The measurement of lipoprotein oxidizability also showed a significant increase in plasma of infected animals. Together, our findings support the idea that products of oxidative stress, as well as the immune response against the parasite are crucial to changes in kidney architecture and microvascular endothelial permeability of BALB/c mice infected with P. berghei ANKA.

Hypoactivity of the central dopaminergic system and autistic-like behavior induced by a single early prenatal exposure to lipopolysaccharide

The aim of the present study was to evaluate the behavioral patterns associated with autism and the prevalence of these behaviors in males and females, to verify whether our model of lipopolysaccharide (LPS) administration represents an experimental model of autism. For this, we prenatally exposed Wistar rats to LPS (100 mu g/kg, intraperitoneally, on gestational day 9.5), which mimics infection by gram-negative bacteria. Furthermore, because the exact mechanisms by which autism develops are still unknown, we investigated the neurological mechanisms that might underlie the behavioral alterations that were observed. Because we previously had demonstrated that prenatal LPS decreases striatal dopamine (DA) and metabolite levels, the striatal dopaminergic system (tyrosine hydroxylase [TH] and DA receptors D1a and D2) and glial cells (astrocytes and microglia) were analyzed by using immunohistochemistry, immunoblotting, and real-time PCR. Our results show that prenatal LPS exposure impaired communication (ultrasonic vocalizations) in male pups and learning and memory (T-maze spontaneous alternation) in male adults, as well as inducing repetitive/restricted behavior, but did not change social interactions in either infancy (play behavior) or adulthood in females. Moreover, although the expression of DA receptors was unchanged, the experimental animals exhibited reduced striatal TH levels, indicating that reduced DA synthesis impaired the striatal dopaminergic system. The expression of glial cell markers was not increased, which suggests that prenatal LPS did not induce permanent neuroinflammation in the striatum. Together with our previous finding of social impairments in males, the present findings demonstrate that prenatal LPS induced autism-like effects and also a hypoactivation of the dopaminergic system. (c) 2012 Wiley Periodicals, Inc.

Biological and behavioral parameters of the parasitoid Cotesia flavipes (Hymenoptera: Braconidae) are altered by the pathogen Nosema sp (Microsporidia: Nosematidae)

A major issue for mass rearing of insects concerns sanitary conditions and disease. Microsporidian infection (Nosema sp.) in laboratory colonies of Diatraea saccharalis (Fabr.) (Lepidoptera: Crambidae), used in producing the parasitoid. Cotesia flavipes Cameron (Hymenoptera: Braconidae), is representative of the problems faced by growers and industry. Although C. flavipes has been produced for several years in Brazil for biological control of D. saccharalis, we have only recently observed that the parasitoid becomes infected when developing inside hosts infected with Nosema sp. We assessed the effects of Nosema sp. on C. flavipes, including the ability to locate and select hosts, and evaluated pathogen transmission. Third instar larvae of D. saccharalis were inoculated with Nosema sp. spores at different concentrations and were parasitized when larvae reached fifth instar. Heavily infected D. saccharalis larvae did not support parasitism. Parasitoids that developed in infected D. saccharalis larvae exhibited increased duration of larval and pupal stages, decreased adult longevity and number of offspring, and reduced tibia size compared to parasitoids developing in uninfected D. saccharalis larvae. Infection by Nosema sp. reduced the ability of the C. flavipes parasitoid to distinguish between volatiles released by the sugarcane infested by healthy larvae and pure air. Uninfected parasitoids preferred plants infested with uninfected hosts. But infected C. flavipes did not differentiate between uninfected hosts and those infected with Nosema sp. The pathogen is transmitted from host to parasitoids and parasitoids to hosts. Pathogenic effects of the microsporidium in C. flavipes are sufficiently severe to justify disease management efforts, particularly considering the importance of C. flavipes as a biological control agent in sugarcane. (C) 2012 Elsevier Inc. All rights reserved.

Porphyromonas gingivalis infection at different gestation periods on fetus development and cytokines profile

Oral Diseases (2012) 18, 648654 Aim: Infective agents may affect pregnancy outcomes by deregulating homeostasis. Objectives: The effects of Porphyromonas gingivalis infection before and at different gestation periods were evaluated. Materials and Methods: Wistar rats infected via subcutaneous with P. gingivalis W83, one week before mating (BM), days 1 (PR1) and 11 of gestation (PR11), and controls were evaluated, and samples were obtained at the end of gestation. P. gingivalis was detected by PCR. Cytokine was determined by ELISA. Results: Infected rats had lower maternal gain of weight. Implantation was not observed in 2/12 BM rats. PR11 presented more fetal-placental resorptions and lower placenta/fetus weight than controls. P. gingivalis was detected in placenta and fetus. IL-6 and TNF-a levels were higher in placenta and serum of infected groups, except for TNF-a in placenta of PR1. IL-1 beta levels were higher in placenta of PR11, but lower in serum and placenta of PR1. There were no differences in IL-10 and PGE2 concentrations among the groups (P < 0.05). Conclusions: The experimental infection by P. gingivalis resulted in alterations in the gestational pattern and in fetal development. The consequences of infection at mid-gestation were more severe than at the beginning, possibly due to the induction of pro-inflammatory cytokines in the fetal compartment.

5-Lipoxygenase Deficiency Impairs Innate and Adaptive Immune Responses during Fungal Infection

5-lipoxygenase-derived products have been implicated in both the inhibition and promotion of chronic infection. Here, we sought to investigate the roles of endogenous 5-lipoxygenase products and exogenous leukotrienes during Histoplasma capsulatum infection in vivo and in vitro. 5-LO deficiency led to increased lung CFU, decreased nitric oxide production and a deficient primary immune response during active fungal infection. Moreover, H. capsulatum-infected 5-LO-/- mice showed an intense influx of neutrophils and an impaired ability to generate and recruit effector T cells to the lung. The fungal susceptibility of 5-LO-/- mice correlated with a lower rate of macrophage ingestion of IgG-H. capsulatum relative to WT macrophages. Conversely, exogenous LTB4 and LTC4 restored macrophage phagocytosis in 5-LO deficient mice. Our results demonstrate that leukotrienes are required to control chronic fungal infection by amplifying both the innate and adaptive immune response during histoplasmosis.

Potential costs of bacterial infection on storage protein gene expression and reproduction in queenless Apis mellifera worker bees on distinct dietary regimes

Insects are able to combat infection by initiating an efficient immune response that involves synthesizing antimicrobial peptides and a range of other defense molecules. These responses may be costly to the organism, resulting in it exploiting endogenous resources to maintain homeostasis or support defense to the detriment of other physiological needs. We used queenless worker bees on distinct dietary regimes that may alter hemolymph protein storage and ovary activation to investigate the physiological costs of infection with Serratia marcescens. The expression of the genes encoding the storage proteins vitellogenin and hexamerin 70a, the vitellogenin receptor, and vasa (which has a putative role in reproduction), was impaired in the infected bees. This impairment was mainly evident in the bees fed beebread, which caused significantly higher expression of these genes than did royal jelly or syrup, and this was confirmed at the vitellogenin and hexamerin 70a protein levels. Beebread was also the only diet that promoted ovary activation in the queenless bees, but this activation was significantly impaired by the infection. The expression of the genes encoding the storage proteins apolipophorins-I and -III and the lipophorin receptor was not altered by infection regardless the diet provided to the bees. Similarly, the storage of apolipophorin-I in the hemolymph was only slightly impaired by the infection, independently of the supplied diet. Taken together these results indicate that, infection demands a physiological cost from the transcription of specific protein storage-related genes and from the reproductive capacity. (C) 2012 Elsevier Ltd. All rights reserved.

Enhanced phagocytosis of Corynebacterium pseudotuberculosis by monocyte-macrophage cells from goats naturally infected with caprine arthritis encephalitis virus

Sanches B.G.S., Souza F.N., Azedo M.R., Batista C.F., Bertagnon H.G., Blagitz M.G. & Della Libera A.M.M.P. 2012. [Enhanced phagocytosis of Corynebacterium pseudotuberculosis by monocyte-macrophage cells from goats naturally infected with caprine arthritis encephalitis virus.] Fagocitose intensificada de Corynebacterium pseudotuberculosis por celulas da serie monocito-macrofago de caprinos naturalmente infectados pelo virus da artrite encefalite. Pesquisa Veterinaria Brasileira 32(12):1225-1229. Departamento de Clinica Medica, Faculdade de Medicina Veterinaria e Zootecnia, Universidade de Sao Paulo, Avenida Prof. Dr. Orlando Marques de Paiva 87, Cidade Universitaria, Sao Paulo, SP 05508-270, Brazil. E-mail: camilafb@usp.br Caprine arthritis encephalitis (CAE) and caseous lymphadenitis (CL) have high incidence and transmissibility in small ruminants. Since both virus have tropism for macrophages and monocytes and affect the innate immune response, it is believed that CAE can predispose the animal to infection by Corynebacteruim pseudotuberculosis, the etiological agent of CL. To confirm this hypothesis, we evaluated phagocytosis from the monocyte-macrophage cells from 30 Saanen goats. Goats were uniformly divided in two groups according to results of agar gel immunodiffusion test for CAE virus (CAEV). Peripheral blood mononuclear cells were isolated by density gradient centrifugation and the monocyte-macrophage cells were isolated from the mononuclear cells by their adhesion properties in plaques. Afterwards, phagocytosis of C. psudotuberculosis was performed for two hours at 37 degrees C, 5% of CO2, and assessed by microscopic visualization. There was no difference in the percentage of monocyte-macrophage cells that phagocytozed C. bovis between groups (P = 0.41). However, when phagocytosis rates were classified according to the number of C. pseudotuberculosis phagocyted, the percentage of monocyte-macrophage cells that internalized more than 12 bacteria were higher in serologically CAEV positive animals compared to the serologically negative ones (P < 0.001). Furthermore, a positive and significant correlation (r = 0.488; P = 0.006) between the percentage of monocyte-macrophage cells that internalized more than 12 bacteria and the percentage of monocyte that were carrying out phagocytosis was also encountered in serologically CAEV positive goats, however the same were not observed in serologically negative ones. These results demonstrated an alteration in the intensity of C. pseudotuberculosis phagocytosis by monocytes-macrophages from goats infected by CAEV. Thus, these results indicated that goats infected with CAEV may be more susceptible to CL.

Pathogenesis of reproductive failure induced by Trypanosoma vivax in experimentally infected pregnant ewes

The present study was aimed at investigating the effect of experimental infection by Trypanosoma vivax in different stages of pregnancy, determining the pathogenesis of reproductive failure, and confirming transplacental transmission. We used 12 pregnant ewes distributed into four experimental groups: G1, was formed by three ewes infected with T. vivax in the first third of pregnancy (30 days); G2 comprised three infected ewes in the final third of pregnancy (100 days); G3 and G4 were composed of three non-infected ewes with the same gestational period, respectively. Each ewe of G1 and G2 was inoculated with 1.25 × 105 tripomastigotes. Clinical examination, determination of parasitemia, serum biochemistry (albumin, total protein, glucose, cholesterol, and urea), packed cell volume (PCV), serum progesterone, and pathological examination were performed. Placenta, amniotic fluid, blood and tissues from the fetuses and stillbirths were submitted to PCR. Two ewes of G1 (Ewe 1 and 3) presented severe infection and died in the 34th and 35th days post-infection (dpi), respectively; but both fetuses were recovered during necropsy. In G2, Ewe 5 aborted two fetuses on the 130th day (30 dpi) of pregnancy; and Ewe 6 aborted one fetus in the 140th day (40 dpi) of gestation. Ewes 2 and 4 delivered two weak lambs that died five days after birth. Factors possibly involved with the reproductive failure included high parasitemia, fever, low PCV, body score, serum glucose, total protein, cholesterol, and progesterone. Hepatitis, pericarditis, and encephalitis were observed in the aborted fetuses. The presence of T. vivax DNA in the placenta, amniotic fluid, blood, and tissues from the fetuses confirms the transplacental transmission of the parasite. Histological lesion in the fetuses and placenta also suggest the involvement of the parasite in the etiopathogenesis of reproductive failure in ewes.

Pathogenesis of reproductive failure induced by Trypanosoma vivax in experimentally infected pregnant ewes

The present study was aimed at investigating the effect of experimental infection by Trypanosoma vivax in different stages of pregnancy, determining the pathogenesis of reproductive failure, and confirming transplacental transmission. We used 12 pregnant ewes distributed into four experimental groups: G1, was formed by three ewes infected with T. vivax in the first third of pregnancy (30 days); G2 comprised three infected ewes in the final third of pregnancy (100 days); G3 and G4 were composed of three non-infected ewes with the same gestational period, respectively. Each ewe of G1 and G2 was inoculated with 1.25 × 105 tripomastigotes. Clinical examination, determination of parasitemia, serum biochemistry (albumin, total protein, glucose, cholesterol, and urea), packed cell volume (PCV), serum progesterone, and pathological examination were performed. Placenta, amniotic fluid, blood and tissues from the fetuses and stillbirths were submitted to PCR. Two ewes of G1 (Ewe 1 and 3) presented severe infection and died in the 34th and 35th days post-infection (dpi), respectively; but both fetuses were recovered during necropsy. In G2, Ewe 5 aborted two fetuses on the 130th day (30 dpi) of pregnancy; and Ewe 6 aborted one fetus in the 140th day (40 dpi) of gestation. Ewes 2 and 4 delivered two weak lambs that died five days after birth. Factors possibly involved with the reproductive failure included high parasitemia, fever, low PCV, body score, serum glucose, total protein, cholesterol, and progesterone. Hepatitis, pericarditis, and encephalitis were observed in the aborted fetuses. The presence of T. vivax DNA in the placenta, amniotic fluid, blood, and tissues from the fetuses confirms the transplacental transmission of the parasite. Histological lesion in the fetuses and placenta also suggest the involvement of the parasite in the etiopathogenesis of reproductive failure in ewes.

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.

Pathogenic Mycobacterium bovis strains differ in their ability to modulate the proinflammatory activation phenotype of macrophages

Background: Tuberculosis, caused by Mycobacterium tuberculosis or Mycobacterium bovis, remains one of the leading infectious diseases worldwide. The ability of mycobacteria to rapidly grow in host macrophages is a factor contributing to enhanced virulence of the bacteria and disease progression. Bactericidal functions of phagocytes are strictly dependent on activation status of these cells, regulated by the infecting agent and cytokines. Pathogenic mycobacteria can survive the hostile environment of the phagosome through interference with activation of bactericidal responses. To study the mechanisms employed by highly virulent mycobacteria to promote their intracellular survival, we investigated modulating effects of two pathogenic M. bovis isolates and a reference M. tuberculosis H37Rv strain, differing in their ability to multiply in macrophages, on activation phenotypes of the cells primed with major cytokines regulating proinflammatory macrophage activity. Results: Bone marrow- derived macrophages obtained from C57BL/6 mice were infected by mycobacteria after a period of cell incubation with or without treatment with IFN-gamma, inducing proinflammatory type-1 macrophages (M1), or IL-10, inducing anti-inflammatory type-2 cells (M2). Phenotypic profiling of M1 and M2 was then evaluated. The M. bovis strain MP287/03 was able to grow more efficiently in the untreated macrophages, compared with the strains B2 or H37Rv. This strain induced weaker secretion of proinflammatory cytokines, coinciding with higher expression of M2 cell markers, mannose receptor (MR) and arginase-1 (Arg-1). Treatment of macrophages with IFN-gamma and infection by the strains B2 and H37Rv synergistically induced M1 polarization, leading to high levels of inducible nitric oxide synthase (iNOS) expression, and reduced expression of the Arg-1. In contrast, the cells infected with the strain MP287/03 expressed high levels of Arg-1 which competed with iNOS for the common substrate arginine, leading to lower levels of NO production. Conclusions: The data obtained demonstrated that the strain, characterized by increased growth in macrophages, down- modulated classical macrophage activation, through induction of an atypical mixed M1/M2 phenotype.