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‣ Relação sazonal entre reprodução, imunidade e ocorrência de endoparasitas em anfíbios anuros da Caatinga; Seasonal relationship between reproduction, immunity and occurence of endoparasites of anuran amphibians of Caatinga

Madelaire, Carla Bonetti
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 19/10/2012 Português
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A grande maioria das espécies de anfíbios anuros apresenta um padrão de reprodução sazonal, caracterizado nos machos por um pico de andrógenos que desencadeia maturação testicular, bem como manutenção do comportamento sexual. No entanto, os altos níveis de andrógenos podem apresentar um efeito imunossupressor, podendo também aumentar a probabilidade de infecções parasitárias. A Caatinga brasileira é caracterizada por altas temperaturas e chuvas sazonais e imprevisíveis que determinam o padrão reprodutivo e de atividade dos anuros dessa região, algumas espécies como P. diplolister apresentam comportamento de estivação durante a seca, já Rhinella Jimi e R. granulosa permanecem ativos quanto ao forrageamento durante este período. As drásticas variações deste ambiente poderiam acentuar os ajustes fisiológicos apresentados por essas espécies, principalmente para a espécie estivadora. Foram estudadas as inter-relações entre caracteres morfológicos, fisiológicos e parasitológicos dessas três espécies de anuros, em três períodos distintos, (A) durante a temporada reprodutiva, em um período entre dois surtos reprodutivos (período entre chuvas); (B) durante um surto reprodutivo que acompanhou um evento de chuvas e (C) no período da seca. As duas espécies de Rhinella apresentaram evidências de modulações imunológicas de acordo com período...

‣ Heat shock protein production and immunity and altered fetal development in diabetic pregnant rats

Saito, Felipe Hiroshi; Damasceno, Débora Cristina; Dallaqua, Bruna; Linhares, Iara Moreno; Rudge, Marilza Vieira Cunha; De Mattos Paranhos Calderon, Iracema; Witkin, Steven S.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 25-33
Português
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We evaluated associations between the concentrations of heat shock proteins (hsp60 and hsp70) and their respective antibodies, alterations in maternal reproductive performance, and fetal malformations in pregnant rats with hyperglycemia. Mild diabetes (MD) or severe diabetes (SD) was induced in Sprague-Dawley rats prior to mating; non-treated non-diabetic rats (ND) served as controls. On day 21 of pregnancy, maternal blood was analyzed for hsp60 and hsp70 and their antibodies; and fetuses were weighed and analyzed for congenital malformations. Hsp and anti-hsp levels were correlated with blood glucose levels during gestation. There was a positive correlation between hsp60 and hsp70 levels and the total number of malformations (R∈=∈0.5908, P∈=∈0.0024; R∈=∈0.4877, P∈=∈0.0134, respectively) and the number of malformations per fetus (R∈=∈0.6103, P∈=∈0.0015; R∈=∈0.4875, P∈=∈0.0134, respectively). The anti-hsp60 IgG concentration was correlated with the number of malformations per fetus (R∈=∈0.3887, P∈=∈0.0451) and the anti-hsp70 IgG level correlated with the total number of malformations (R∈=∈0.3999, P∈=∈0.0387). Moreover, both hsp and anti-hsp antibodies showed negative correlations with fetal weight. The results suggest that there is a relationship between hsp60 and hsp70 levels and their respective antibodies and alterations in maternal reproductive performance and impaired fetal development and growth in pregnancies associated with diabetes. © 2012 Cell Stress Society International.

‣ Alternative male reproductive tactics and the immunocompetence handicap in the azorean rock-pool blenny, Parablennius parvicornis

Ros, Albert F. H.; Bouton, Niels; Santos, Ricardo Serrão; Oliveira, Rui Filipe
Fonte: The Royal Society Publicador: The Royal Society
Tipo: Artigo de Revista Científica
Publicado em //2006 Português
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In the Azorean rock-pool blenny (Parablennius parvicornis) reproductively active males display alternative morphotypes, which differ in the expression of secondary sexual characters (SSC). Males expressing SSC, theMCmorphotype, have high androgen levels and compete for crevices that will be visited by females to spawn.MCmales holding nests court females and care for the eggs. Males with low expression of SSC, the MK morphotype, have low levels of androgens and reproduce by stealing fertilizations from the MC males. Based on the hypothesis that androgens are immunosuppressive, we expected these morphotypes to differ in immunocompetence. To test this hypothesis, we conducted a field study in which we collected repeated blood samples to monitor leukocyte populations (blood smears), and to measure the primary antibody response of males that were experimentally challenged with a foreign non-pathogenic antigen (sheep red blood cells). Circulating levels of 11-ketotestosterone and testosterone were higher in MC males than in MK males. Neither granulocyte nor thrombocyte counts did covariate with androgens or male tactic. In contrast, lymphocyte counts and humoral antibody response were negatively correlated with body size, and as expected...

‣ Epitope Mapping Porcine Reproductive and Respiratory Syndrome Virus by Phage Display: the nsp2 Fragment of the Replicase Polyprotein Contains a Cluster of B-Cell Epitopes

Oleksiewicz, M. B.; Bøtner, A.; Toft, P.; Normann, P.; Storgaard, T.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /04/2001 Português
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We screened phage display libraries of porcine reproductive and respiratory syndrome virus (PRRSV) protein fragments with sera from experimentally infected pigs to identify linear B-cell epitopes that are commonly recognized during infection in vivo. We identified 10 linear epitope sites (ES) 11 to 53 amino acids in length. In the replicase polyprotein, a total of eight ES were identified, six of which localized to the Nsp2 replicase polyprotein processing end product. In the structural proteins, a total of two ES were identified, in the ORF3 and ORF4 minor envelope glycoproteins. The ORF4 ES was previously identified by monoclonal antibody mapping (J. J. M. Meulenberg, A. P. van Nieuwstadt, A. van Essen-Zandenbergen, and J. P. M. Langeveld, J. Virol. 71:6061–6067, 1997), but its immunogenicity had not been examined in pigs. We found that six experimentally PRRSV-infected pigs consistently had very high antibody titers against the ORF4 ES. In some animals, sera diluted 1:62,500 still gave weak positive enzyme immunoassay reactivity against the ORF4 ES. This hitherto unrecognized immunodominance likely caused phages displaying the ORF4 ES to outcompete phages displaying other ES during library screening with porcine sera and accounted for our failure to identify more than two ES in the structural genes of PRRSV. Genetic analysis showed that variable ES were also the most immunogenic in vivo. Serological analysis indicated differences in the immunoglobulin A responses between short-term and longer-term viremic pigs towards some ES. The implications of these findings for PRRSV diagnostics and immunopathogenesis are discussed.

‣ In Utero Infection by Porcine Reproductive and Respiratory Syndrome Virus Is Sufficient To Increase Susceptibility of Piglets to Challenge by Streptococcus suis Type II

Feng, Wen-hai; Laster, S. M.; Tompkins, M.; Brown, T.; Xu, J.-S.; Altier, C.; Gomez, W.; Benfield, D.; McCaw, M. B.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /05/2001 Português
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Porcine reproductive and respiratory syndrome (PRRS) consistently elevates the frequency of disease and mortality in young pigs. Many different secondary bacterial diseases occur in PRRS virus (PRRSV)-infected pigs. However, to date, establishing a reproducible experimental model of PRRSV infection in weaned pigs, with subsequent clinical disease following secondary bacterial challenge, has been difficult. PRRSV is frequently isolated during outbreaks from weak-born piglets affected by secondary bacterial diseases. This study was performed to investigate the potential role of intrauterine PRRSV infection on piglet susceptibility to secondary bacterial infection. PRRSV-free pregnant sows were intranasally infected at 98 days of gestation with PRRSV strain SD 23983. All piglets born to the PRRSV-infected sows were viremic. Piglets were removed from the sows at birth and deprived of colostrum. Piglets from PRRSV-infected and noninfected sows were randomly assigned to Streptococcus suis challenge or control subgroups. At 5 days of age, piglets were challenged intranasally with strain MN 87555 of S. suis type II. Total and differential leukocyte counts were performed on blood samples collected at 3 days of age. The numbers of leukocytes...

‣ Experimental Inoculation of Conventional Pigs with Porcine Reproductive and Respiratory Syndrome Virus and Porcine Circovirus 2

Rovira, A.; Balasch, M.; Segalés, J.; García, L.; Plana-Durán, J.; Rosell, C.; Ellerbrok, H.; Mankertz, A.; Domingo, M.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /04/2002 Português
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Postweaning multisystemic wasting syndrome (PMWS) is a disease of nursery and fattening pigs characterized by growth retardation, paleness of the skin, dyspnea, and increased mortality rates. Porcine circovirus 2 (PCV2) has been demonstrated to be the cause of PMWS. However, other factors are needed for full development of the syndrome, and porcine reproductive and respiratory syndrome virus (PRRSV) infection has been suggested to be one of them. Twenty-four conventional 5-week-old pigs were distributed in four groups: control (n = 5), PRRSV inoculated (n = 5), PCV2 inoculated (n = 7), and PRRSV and PCV2 inoculated (n = 7). The two groups inoculated with PRRSV showed growth retardation. Pigs inoculated with both PRRSV and PCV2 had increased rectal temperature. One of these pigs developed wasting, had severe respiratory distress, and died. The most important microscopic lesion in pigs inoculated with PCV2 was lymphocyte depletion with histiocytic infiltration of the lymphoid organs, more severe and in a wider range of tissues in doubly inoculated pigs. Interstitial pneumonia was observed in the three inoculated groups. PCV2 nucleic acid was found by in situ hybridization in larger amounts and in a wider range of lymphoid tissues in PRRSV- and PCV2-inoculated than in PCV2-inoculated pigs. TaqMan PCR was performed to quantify the PCV2 loads in serum during the experiment. PCV2 loads were higher in doubly inoculated pigs than in pigs inoculated with PCV2 alone. These findings indicate that severe disease can be reproduced in conventional 5-week-old pigs by inoculation of PRRSV and PCV2. Moreover...

‣ Identification of Neutralizing and Nonneutralizing Epitopes in the Porcine Reproductive and Respiratory Syndrome Virus GP5 Ectodomain

Ostrowski, M.; Galeota, J. A.; Jar, A. M.; Platt, K. B.; Osorio, F. A.; Lopez, O. J.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /05/2002 Português
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After infection of swine with porcine reproductive and respiratory syndrome virus (PRRSV), there is a rapid rise of PRRSV-specific nonneutralizing antibodies (NNA), while neutralizing antibodies (NA) are detectable not sooner than 3 weeks later. To characterize neutralizing epitopes, we selected phages from a 12-mer phage display library using anti-PRRSV neutralizing monoclonal antibody (MAb) ISU25-C1. In addition, phages carrying peptides recognized by swine antibodies with high seroneutralizing titer were isolated after subtracting from the library those clones binding to swine anti-PRRSV serum with no neutralizing activity. Two epitopes located in the ectodomain of PRRSV GP5 were identified. One of these epitopes, which we named epitope B, was recognized both by neutralizing MAb ISU25-C1 and swine neutralizing serum (NS) but not by swine nonneutralizing serum (NNS), indicating that it is a neutralizing epitope. Epitope B is sequential, conserved among isolates, and not immunodominant. Antibodies directed against it are detected in serum late after infection. In contrast, the other epitope, which we named epitope A, is hypervariable and immunodominant. Antibodies against it appear early after infection with PRRSV. This epitope is recognized by swine NNA but is not recognized by either neutralizing MAb ISU25-C1 or swine NA...

‣ The Level of Virus-Specific T-Cell and Macrophage Recruitment in Porcine Reproductive and Respiratory Syndrome Virus Infection in Pigs Is Independent of Virus Load

Xiao, Zhengguo; Batista, Laura; Dee, Scott; Halbur, Patrick; Murtaugh, Michael P.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /06/2004 Português
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Porcine reproductive and respiratory syndrome virus (PRRSV) is the most important infectious disease agent of pigs worldwide, causing reproductive failure in pregnant sows and respiratory problems in nursing and growing pigs. PRRSV infection is characterized by a prolonged viremia of 30 or more days and an extended persistent infection of lymphoid tissues. To better understand the immunological basis for prolonged acute and persistent PRRSV infection, we have examined the cell-mediated immune (CMI) response throughout the course of infection and compared the results to the local distribution and abundance of PRRSV in infected tissues. PRRSV-specific T cells, enumerated by gamma interferon enzyme-linked immunospot assay, did not appear until 2 weeks after PRRSV inoculation, and their abundance exhibited substantial variation over time and among animals. In all cases the T-cell response was transient. High levels of viral RNA were present in lymphoid tissues of all animals in the acute phase of infection. Viral loads were decreased 1,000-fold or more in persistent infections, with the primary sites of persistence being tonsil, sternal lymph node, and inguinal lymph node. The abundance of virus-specific T cells in either acutely or persistently infected animals was highly variable and showed no correlation to the level of virus in lymphoid tissues. No significant difference in antigen-specific T-cell abundance was observed in secondary lymphoid tissues in either acute or persistent infection except for tonsil...

‣ Influence of Exogenous Reproductive Hormones on Specific Antibody Production in Genital Secretions after Vaginal Vaccination with Recombinant Cholera Toxin B Subunit in Humans

Wassen, Lotta; Jertborn, Marianne
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /02/2006 Português
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The objective of this study was to investigate the influence of exogenous reproductive hormones on the local and systemic production of specific immunoglobulin A (IgA) and IgG antibodies after vaginal vaccination with recombinant cholera toxin subunit B (CTB). Three groups of women using either progesterone-containing intrauterine devices (n = 9), oral contraceptives (n = 8), or no hormonal contraceptive methods (n = 9) were vaginally immunized twice, 2 weeks apart. Cervical secretions, vaginal fluids, and serum were collected before and after vaccination. Total and CTB-specific IgA and IgG antibodies in genital secretions and serum were analyzed by enzyme-linked immunosorbent assay. A majority of the women presented strong CTB-specific IgA and IgG antibody responses in cervicovaginal secretions after vaccination, whereas the antitoxin responses in serum were weaker. Exogenously administered steroid hormones did not seem to have any impact on the production of specific antibodies. Both the frequencies and the magnitudes of IgA and IgG antitoxin responses in genital secretions were comparable among the three immunization groups. An association, in particular for IgA, was found between the magnitudes of the CTB-specific antibody responses in cervical secretions and vaginal fluids after vaccination. The sensitivities and positive predictive values of vaginal antibody analyses to reflect responses in cervical secretions were also high...

‣ A Full-Length cDNA Infectious Clone of North American Type 1 Porcine Reproductive and Respiratory Syndrome Virus: Expression of Green Fluorescent Protein in the Nsp2 Region▿

Fang, Ying; Rowland, Raymond R. R.; Roof, Michael; Lunney, Joan K.; Christopher-Hennings, Jane; Nelson, Eric A.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
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The recent emergence of a unique group of North American type 1 porcine reproductive and respiratory syndrome virus (PRRSV) in the United States presents new disease control problems for a swine industry that has already been impacted seriously by North American type 2 PRRSV. In this study, a full-length cDNA infectious clone was generated from a low-virulence North American type 1 PRRSV isolate, SD01-08. In vitro studies demonstrated that the cloned virus maintained growth properties similar to those of the parental virus. Virological, pathological, and immunological observations from animals challenged with cloned viruses were similar to those from animals challenged with the parental virus and a modified live virus vaccine. To further explore the potential use as a viral backbone for expressing foreign genes, the green fluorescent protein (GFP) was inserted into a unique deletion site located at amino acid positions 348 and 349 of the predicted Nsp2 region in the virus, and expression of the Nsp2-GFP fusion protein was visualized by fluorescent microscopy. The availability of this North American type 1 infectious clone provides an important research tool for further study of the basic viral biology and pathogenic mechanisms of this group of type 1 PRRSV in the United States.

‣ The 30-Amino-Acid Deletion in the Nsp2 of Highly Pathogenic Porcine Reproductive and Respiratory Syndrome Virus Emerging in China Is Not Related to Its Virulence▿

Zhou, Lei; Zhang, Jialong; Zeng, Jingwen; Yin, Shuoyan; Li, Yanhua; Zheng, Linying; Guo, Xin; Ge, Xinna; Yang, Hanchun
Fonte: American Society for Microbiology (ASM) Publicador: American Society for Microbiology (ASM)
Tipo: Artigo de Revista Científica
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During the past 2 years, an atypical clinical outbreak, caused by a highly pathogenic porcine reproductive and respiratory syndrome virus (PRRSV) with a unique 30-amino-acid deletion in its Nsp2-coding region, was pandemic in China. In this study, we generated four full-length infectious cDNA clones: a clone of the highly virulent PRRSV strain JXwn06 (pWSK-JXwn), a clone of the low-virulence PRRSV strain HB-1/3.9 (pWSK-HB-1/3.9), a chimeric clone in which the Nsp2 region containing the 30-amino-acid deletion was replaced by the corresponding region of the low-virulence PRRSV strain HB-1/3.9 (pWSK-JXwn-HB1nsp2), and a mutated HB-1/3.9 clone with the same deletion in Nsp2 as JXwn06 (pWSK-HB1-ND30). We also investigated the pathogenicities of the rescued viruses (designated RvJXwn, RvJXwn-HB1nsp2, RvHB-1/3.9, and RvHB1-ND30, respectively) in specific-pathogen-free piglets in order to determine the role of the 30-amino-acid deletion in the virulence of the highly pathogenic PRRSV. All the rescued viruses could replicate stably in MARC-145 cells. Our findings indicated that RvJXwn-HB1nsp2 retained high virulence for piglets, like RvJXwn and the parental virus JXwn06, although the survival time of piglets infected with RvJXwn-HB1nsp2 was obviously prolonged. RvHB1-ND30 exhibited low virulence for piglets...

‣ Reassessing the Human Immunodeficiency Virus Type 1 Life Cycle through Age-Structured Modeling: Life Span of Infected Cells, Viral Generation Time, and Basic Reproductive Number, R0▿ †

Althaus, Christian L.; De Vos, Anneke S.; De Boer, Rob J.
Fonte: American Society for Microbiology (ASM) Publicador: American Society for Microbiology (ASM)
Tipo: Artigo de Revista Científica
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The rapid decay of the viral load after drug treatment in patients infected with human immunodeficiency virus type 1 (HIV-1) has been shown to result from the rapid loss of infected cells due to their high turnover, with a generation time of around 1 to 2 days. Traditionally, viral decay dynamics after drug treatment is investigated using models of differential equations in which both the death rate of infected cells and the viral production rate are assumed to be constant. Here, we describe age-structured models of the viral decay dynamics in which viral production rates and death rates depend on the age of the infected cells. In order to investigate the effects of age-dependent rates, we compared these models with earlier descriptions of the viral load decay and fitted them to previously published data. We have found no supporting evidence that infected-cell death rates increase, but cannot reject the possibility that viral production rates increase, with the age of the cells. In particular, we demonstrate that an exponential increase in viral production with infected-cell age is perfectly consistent with the data. Since an exponential increase in virus production can compensate for the exponential loss of infected cells, the death rates of HIV-1-infected cells may be higher than previously anticipated. We discuss the implications of these findings for the life span of infected cells...

‣ Estimation of the Initial Viral Growth Rate and Basic Reproductive Number during Acute HIV-1 Infection▿

Ribeiro, Ruy M.; Qin, Li; Chavez, Leslie L.; Li, Dongfeng; Self, Steven G.; Perelson, Alan S.
Fonte: American Society for Microbiology (ASM) Publicador: American Society for Microbiology (ASM)
Tipo: Artigo de Revista Científica
Português
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During primary infection, the number of HIV-1 particles in plasma increases rapidly, reaches a peak, and then declines until it reaches a set point level. Understanding the kinetics of primary infection, and its effect on the establishment of chronic infection, is important in defining the early pathogenesis of HIV. We studied the viral dynamics of very early HIV-1 infection in 47 subjects identified through plasma donation screening. We calculated how fast the viral load increases and how variable this parameter is among individuals. We also estimated the basic reproductive ratio, the number of new infected cells generated by an infectious cell at the start of infection when target cells are not limiting. The initial viral doubling time had a median of 0.65 days with an interquartile range of 0.56 to 0.91 days. The median basic reproductive ratio was 8.0 with an interquartile range of 4.9 to 11. In 15 patients, we also observed the postpeak decay of plasma virus and found that the virus decay occurred at a median rate of 0.60 day−1, corresponding to a half-life of 1.2 days. The median peak viral load was 5.8 log10 HIV-1 RNA copies/ml, and it was reached 14 days after the virus was quantifiable with an assay, with a lower limit of detection of 50 copies/ml. These results characterize the early plasma viral dynamics in acute HIV infection better than it has been possible thus far. They also better define the challenge that the immune response (or therapeutic intervention) has to overcome to defeat HIV at this early stage.

‣ A Variable Region in GP4 of European-Type Porcine Reproductive and Respiratory Syndrome Virus Induces Neutralizing Antibodies Against Homologous But Not Heterologous Virus Strains

Vanhee, Merijn; Costers, Sarah; Van Breedam, Wander; Geldhof, Marc F.; Van Doorsselaere, Jan; Nauwynck, Hans J.
Fonte: Mary Ann Liebert, Inc. Publicador: Mary Ann Liebert, Inc.
Tipo: Artigo de Revista Científica
Publicado em /08/2010 Português
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Porcine reproductive and respiratory syndrome virus (PRRSV) can induce severe reproductive failure in sows, and is involved in the porcine respiratory disease complex. The glycoprotein GP4 of the European prototype PRRSV strain Lelystad virus (LV) contains a linear neutralizing epitope that is located in a highly variable region. The current study aimed to evaluate the antibody response against this and other epitopes on GP4 to infection of pigs with European-type PRRSV. It was shown that three virus strains, differing in the region that corresponds to the neutralizing epitope on GP4 of LV, strongly induce antibodies against this area. Antibodies against the epitopes of the different virus strains were purified from polyclonal swine sera, and used in virus-neutralization tests on primary alveolar macrophages. This revealed that antibodies against the variable region in GP4 of different virus strains are able to neutralize infection with homologous but not heterologous virus strains.

‣ Porcine Reproductive and Respiratory Syndrome Virus–Induced Immunosuppression Exacerbates the Inflammatory Response to Porcine Respiratory Coronavirus in Pigs

Renukaradhya, Gourapura J.; Alekseev, Konstantin; Jung, Kwonil; Fang, Ying; Saif, Linda J.
Fonte: Mary Ann Liebert, Inc. Publicador: Mary Ann Liebert, Inc.
Tipo: Artigo de Revista Científica
Publicado em /10/2010 Português
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We performed a comprehensive analysis of innate and adaptive immune responses in dual-virus infected pigs to understand whether a pre-existing immunomodulatory respiratory viral infection affects the overall immunity to a subsequent porcine respiratory coronavirus (PRCV) infection in pigs. Pigs were either mock-infected or infected with porcine reproductive and respiratory syndrome virus (PRRSV), a virus known to cause immunosuppressive respiratory disease, and then pigs were co-infected with PRCV, which normally causes subclinical respiratory infection. We collected samples for six independent experiments from 178 pigs that were also used for pathological studies. We detected a significant reduction in innate NK-cell-mediated cytotoxic function in PRRSV-infected pigs, which was synergistically further decreased in pigs co-infected with PRCV. Subsequently, in association with clinical signs we observed elevated levels of proinflammatory (IL-6), Th-1 (IL-12), and regulatory (IL-10 and TGF-β) cytokines. Increased frequencies of CD4CD8 double-positive T lymphocytes and myeloid cells, in addition to the elevated Th-1 and proinflammatory cytokines in dual-infected pigs, contributed to the severity of lung disease in pigs. The results of our study clarify how each virus modulates the host innate and adaptive immune responses...

‣ Sequence Diversity of Pan troglodytes Subspecies and the Impact of WFDC6 Selective Constraints in Reproductive Immunity

Ferreira, Zélia; Hurle, Belen; Andrés, Aida M.; Kretzschmar, Warren W.; Mullikin, James C.; Cherukuri, Praveen F.; Cruz, Pedro; Gonder, Mary Katherine; Stone, Anne C.; Tishkoff, Sarah; Swanson, Willie J.; ; Green, Eric D.; Clark, Andrew G.; Seixas, Susa
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica
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Recent efforts have attempted to describe the population structure of common chimpanzee, focusing on four subspecies: Pan troglodytes verus, P. t. ellioti, P. t. troglodytes, and P. t. schweinfurthii. However, few studies have pursued the effects of natural selection in shaping their response to pathogens and reproduction. Whey acidic protein (WAP) four-disulfide core domain (WFDC) genes and neighboring semenogelin (SEMG) genes encode proteins with combined roles in immunity and fertility. They display a strikingly high rate of amino acid replacement (dN/dS), indicative of adaptive pressures during primate evolution. In human populations, three signals of selection at the WFDC locus were described, possibly influencing the proteolytic profile and antimicrobial activities of the male reproductive tract. To evaluate the patterns of genomic variation and selection at the WFDC locus in chimpanzees, we sequenced 17 WFDC genes and 47 autosomal pseudogenes in 68 chimpanzees (15 P. t. troglodytes, 22 P. t. verus, and 31 P. t. ellioti). We found a clear differentiation of P. t. verus and estimated the divergence of P. t. troglodytes and P. t. ellioti subspecies in 0.173 Myr; further, at the WFDC locus we identified a signature of strong selective constraints common to the three subspecies in WFDC6—a recent paralog of the epididymal protease inhibitor EPPIN. Overall...

‣ Molecular identification of Trichinella spiralis nudix hydrolase and its induced protective immunity against trichinellosis in BALB/c mice

Long, Shao Rong; Wang, Zhong Quan; Liu, Ruo Dan; Liu, Li Na; Li, Ling Ge; Jiang, Peng; Zhang, Xi; Zhang, Zi Fang; Shi, Hai Ning; Cui, Jing
Fonte: BioMed Central Publicador: BioMed Central
Tipo: Artigo de Revista Científica
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Background: Nudix hydrolases (Nd) is a widespread superfamily, which is found in all classes of organism, hydrolyse a wide range of organic pyrophosphates and has a ‘housecleaning’ function. The previous study showed that Trichinella spiralis Nd (TsNd) bound to intestinal epithelial cells (IECs), and the vaccination of mice with T7 phage-displayed TsNd polypeptides produced protective immunity. The aim of this study was to clone, express and identify the full-length TsNd and to investigate its immune protection against T. spiralis infection. Methods: The full-length cDNA sequence of TsNd gene encoding a 46 kDa protein from T. spiralis intestinal infective larvae (IIL) was cloned and identified. The antigenicity of rTsNd was analyzed by Western blot. Transcription and expression of TsNd at T. spiralis different stages were observed by RT-PCR and IFT. The levels of the specific total IgG, IgG1 and IgG2a antibodies to rTsNd were determined by ELISA. The immune protection of rTsNd against T. spiralis infection was investigated. Results: Sequence and phylogenetic analysis revealed that TsNd had a nudix motif located at 226-244aa, which had high homology and the closest evolutionary status with T. pseudospiralis. The rTsNd was obtained after expression and purification. Western blot analysis showed that anti-rTsNd serum recognized the native TsNd protein in crude antigens of muscle larvae (ML)...

‣ The impact of exogenous TGFβ1 on male reproductive function.

McGrath, Leanne Jane
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2008 Português
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The TGFβ family of cytokines are potent signalling molecules that regulate tissue development, inflammation and immunity. Previous studies in mice with a null mutation in the Tgfb1 gene (TGFβ1-/- mice) implicate a key role for TGFβ1 in male reproductive function. These mice show profound infertility due to an inability to copulate successfully, associated with reduced testosterone and sperm production. The focus of this project was to 1) further characterize mechanisms underpinning reproductive deficiency in male TGFβ1-/- mice, 2) identify a reliable physiological marker of TGFβ1 availability in vivo, and 3) to determine whether exogenous TGFβ1 administration influences TGFβ1 availability and restores fertility. To investigate the causes of unsuccessful copulation by TGFβ1-/- mice, penis morphometry was examined. Penile organ structure, as assessed by scanning electron microscopy, was comparable between genotypes however a superfluous epidermal covering that impeded penile spine protrusion was evident in TGFβ1-/- mice. The epidermal covering was not due to increased epithelial cell proliferation, as measured by Brdu labelling and immunohistology. Behavioural observations of erectile activity showed that TGFβ1-/- mice achieved spontaneous erections albeit at reduced frequency compared to TGFβ1+/+ mice. The efficacy of exogenous TGFβ1 replacement was evaluated by first identifying measures of in vivo TGFβ1 availability and/or function and selecting an effective route of administration. Serum TGFβ1 and testosterone levels were reliable discriminators of TGFβ1 genotype. Gene expression and phagocytic function of peritoneal macrophages revealed no differences between genotypes. Exogenous sources of TGFβ1 for replacement studies included colostrum...

‣ Mucosal immunology down under: Special interest group in mucosal immunology workshop, Australasian Society for Immunology, Sydney, Australia, 2 December 2007

Cripps, A.; Sutton, P.; Beagley, K.; Robertson, S.; Dunkely, M.
Fonte: Blackwell Publishing Asia Publicador: Blackwell Publishing Asia
Tipo: Artigo de Revista Científica
Publicado em //2008 Português
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The Mucosal Immunology Special Interest Group (SIG-MI) of the Australasian Society of Immunology was formed 14 years ago and has run regular symposia and workshops in conjunction with the Australasian Society of Immunology since that time. In December 2007 the Mucosal Immunology Special Interest Group held a 1-day satellite workshop in conjunction with the annual Australasian Society of Immunology scientific meeting in Sydney to celebrate the decade since hosting the 9th International Congress of Mucosal Immunology (9-ICMI) in 1997, which was also held in Sydney. The meeting that was attended by 65 delegates focussed on 4 session themes: reproductive immunology, respiratory immunology, mucosal immunology of the gastrointestinal tract and mucosal vaccines.; Allan W Cripps, Philip Sutton, Ken Beagley, Sarah Robertson and Margaret Dunkley

‣ Immunity ticks Rhipicephalus sanguineus (Latreille) in crab-eating-fox Cerdocyon thous (Linnaeus) and mongrel dogs; Imunidade a carrapatos Rhipicephalus sanguineus (Acarina: Ixodidae) em cachorro-do-mato Cerdocyon thous (Linnaeus) e no cão doméstico

Ferreira, Beatrix Rossetti; Bechara, Gervásio Henrique
Fonte: Universidade de São Paulo. Faculdade de Medicina Veterinária e Zootecnia Publicador: Universidade de São Paulo. Faculdade de Medicina Veterinária e Zootecnia
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; Formato: application/pdf
Publicado em 04/01/1995 Português
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Many parasite-host relationships are characterized by the development of resistance by the host, thus limiting the number of parasites. However, in the domestic dog X Rhipicephalus sanguineus (brown dog tick) relationship, this does not occur. The hypothesis that the domestic dog has lost this faculty, following the process of its domestication, was investigated by comparing the mongrel dog’s and the crab-eating-fox Cerdocyon thous's capacity of acquiring immunity to R. sanguineus ticks in two situations: after, 3 successive infestations with adult ticks, and immunisation with an unfed whole tick R. sanguineus extract, followed by a challenge infestation with the same tick species. Evaluation of resistance acquisition, in both experimental conditions, was based on nutricional and reproductive performaces of the female ticks during and after infestations. The results showed a small, significant difference between the domestic dog and the crab-eating-fox. Nevertheless, these differences were not considered relevant enough to characterize an effective immunity.; Algumas das relações hospedeiro-parasita são marcadas por desenvolvimento de resistência pelo hospedeiro, limitando o número de parasitas. Tal não ocorre na relação cão doméstico x Rhipicephalus sanguineus (carrapato do cão). Teria o cão doméstico perdido aquela capacidade em seu processo de domesticação? Esta hipótese foi testada em duas condições...