437 research outputs found
Longterm survey (7 years) in a population at risk for Lyme borreliosis: what happens to the seropositive individuals?
In 1986, a 26% seroprevalence of IgG- anti-Borrelia burgdorferi antibodies was observed among 950 orienteers and the incidence of new clinical infections was 0.8%. In 1993, a total of 305 seropositive orienteers were reexamined. During that time, 15 cases (4.9%) of definite/probable Lyme disease occurred in this seropositive group (12 skin manifestations and 3 monoarticular joint manifestations). Among the 12 definite cases, 9 showed new clinical infections (7 EM, 1 acrodermatitis chronica atrophicans, 1 arthritis), and 3 were recurrent (2 EM, 1 arthritis). The annual incidence (0.8%) in this seropositive group was identical to the incidence observed among the whole population in 1986. The individual antibody titer decreased slightly but the seroreversion rate was low (7%). Serology was not very helpful in identifying clinical cases and evolutions, and it can be stated, that a positive serology is much more frequent in this risk group than clinical disease
Recurrent rhinovirus detections in children following a rhinovirus-induced wheezing exacerbation: A retrospective study
Introduction: It is unclear if children with a rhinovirus (RV)-induced wheezing exacerbation are more susceptible to viruses longitudinally, and whether a parental history of asthma and/or allergy impacts their susceptibility. The objective of this study was to determine if RV, RV-A and RV-C related wheezing exacerbations in children were associated with prior or subsequent viral detections and investigate the role of parental history of asthma and allergy. Materials and methods: Children presenting to hospital with acute wheeze were prospectively recruited and tested for respiratory viruses. Data on viruses detected in other respiratory samples (May 1997 to December 2012) were collected from hospital microbiology records and additional RV testing was performed on stored hospital respiratory samples (September 2009 to December 2012). A positive parental history was defined as either parent with self-reported asthma and/or allergy. Results: At recruitment, RV was detected in 69.2% of samples from children with an acute wheezing episode (n=373, 0–16 years of age), with RV-C the most common virus (65.5%). Children with a history of parental asthma and/or allergy and RV at recruitment had a 14-fold increased incidence rate ratio (IRR) of subsequent RV detection (IRR 14.0, 95% CI 1.9–104.1; p=0.01) compared with children without RV at recruitment. Children without this parental history had a reduced incident rate ratio for samples assessed during this time (IRR 0.5, 95% CI 0.3–0.9; p=0.03). Conclusion: Children with a parental history of asthma and/or allergy may become more susceptible to recurrent symptomatic RV infections
Determinação dos parâmetros de fragmentação da Ivermectina para sua identificação por espectrometria de massas.
A Ivermectina Ă© um antiparasitário pertencente ao grupo das lactonas macrocĂclicas, constituĂda por dois homĂłlogos, sendo esses denominados B1a que representa 80% e B1b 20 %. No Brasil, a Ivermectina Ă© um fármaco amplamente utilizado na bovinocultura, contudo seu uso pode gerar resĂduos. Sendo assim, o objetivo deste trabalho foi otimizar os parâmetros de fragmentação e ionização do medicamento no espectrĂ´metro de massas afim de, posteriormente, usá-los em desenvolvimento de mĂ©todo quantitativo de análise por LC-MS/MS. Para a otimização dos parâmetros preparou-se duas soluções de concentrações distintas e fez-se a infusĂŁo no equipamento, de acordo com o sinal dos picos nos espectros obtidos verificou-se a solução que obteve-se um sinal de melhor qualidade. ApĂłs a escolha da concentração ideal para infusĂŁo, determinou-se as melhores condições analĂticas para a fragmentação e ionização da molĂ©cula de Ivermectina. Com o sinal intenso e estável, identificou-se o Ăon precursor da molĂ©cula e dois Ăons provenientes da sua fragmentação. Sendo possĂvel afirmar, devido a razĂŁo m/z apresentada no espectro que a molĂ©cula refere-se ao homĂłlogo B1a. Portanto, com o presente trabalho determinou-se os parâmetros analĂticos mais eficientes de fragmentação no espectrĂ´metro de massas para a Ivermectina e a partir deles constatou-se a presença do homĂłlogo B1a e seus principais fragmentos, conforme descrito na literatura
Lower Respiratory Tract Infection Induced by a Genetically Modified Picornavirus in Its Natural Murine Host
Infections with the picornavirus, human rhinovirus (HRV), are a major cause of wheezing illnesses and asthma exacerbations. In developing a murine model of picornaviral airway infection, we noted the absence of murine rhinoviruses and that mice are not natural hosts for HRV. The picornavirus, mengovirus, induces lethal systemic infections in its natural murine hosts, but small genetic differences can profoundly affect picornaviral tropism and virulence. We demonstrate that inhalation of a genetically attenuated mengovirus, vMC0, induces lower respiratory tract infections in mice. After intranasal vMC0 inoculation, lung viral titers increased, peaking at 24 h postinoculation with viral shedding persisting for 5 days, whereas HRV-A01a lung viral titers decreased and were undetectable 24 h after intranasal inoculation. Inhalation of vMC0, but not vehicle or UV-inactivated vMC0, induced an acute respiratory illness, with body weight loss and lower airway inflammation, characterized by increased numbers of airway neutrophils and lymphocytes and elevated pulmonary expression of neutrophil chemoattractant CXCR2 ligands (CXCL1, CXCL2, CXCL5) and interleukin-17A. Mice inoculated with vMC0, compared with those inoculated with vehicle or UV-inactivated vMC0, exhibited increased pulmonary expression of interferon (IFN-α, IFN-β, IFN-λ), viral RNA sensors [toll-like receptor (TLR)3, TLR7, nucleotide-binding oligomerization domain containing 2 (NOD2)], and chemokines associated with HRV infection in humans (CXCL10, CCL2). Inhalation of vMC0, but not vehicle or UV-inactivated vMC0, was accompanied by increased airway fluid myeloperoxidase levels, an indicator of neutrophil activation, increased MUC5B gene expression, and lung edema, a sign of infection-related lung injury. Consistent with experimental HRV inoculations of nonallergic, nonasthmatic human subjects, there were no effects on airway hyperresponsiveness after inhalation of vMC0 by healthy mice. This novel murine model of picornaviral airway infection and inflammation should be useful for defining mechanisms of HRV pathogenesis in humans
Caracterização fĂsico-quĂmica de nanopartĂculas de diĂłxido de titânio para produção de nanocompĂłsitos.
A percepção de que animais tambĂ©m sentem medo dor e angĂşstia leva a necessidade de desenvolvimento de inĂşmeros mĂ©todos alternativos ao uso de animais em experimentação. Assim, mĂ©todos in vitro sĂŁo uma alternativa para contornar este problema. Baseado em sua biocompatibilidade e sua baixa toxicidade, as nanopartĂculas de diĂłxido de titânio (TiO2NPs) apresentam grande potencial para serem utilizadas na produção de desenvolvimento de matrizes 3D para a bioengenharia de tecidos. Dentro deste contexto, o presente trabalho tem por objetivo caracterizar fisicoquimicamente TiO2NPs para em um futuro utilizá-las para produção de nanocompĂłsitos. Para tanto, TiO2NPs (NM01001a, European Union reference material) foram caracterizadas por tĂ©cnicas espectroscĂłpica (Raman e Infravermelho), bem como por microscopia de força atĂ´mica e espalhamento dinâmico de luz. As TiO2NPs apresentaram geometrias e tamanhos heterogĂŞneos, contudo apresentando pelo menos um dos eixos cardinais com tamanho inferior a 100nm, elevado ĂŤndice de DispersĂŁo (0,526 ± 0,05) e baixa estabilidade coloidal (potencial Zeta de -3,50 ± 0.40 mV). Por sua vez, o material apresentou indicativo de elevado grau de preza, com bandas caracterĂsticas de ligações de Ti-O e grupos OH na superfĂcie da partĂcula, respectivamente em 542 e 686 cm− 1 3427 cm− 1 na espectroscopia e infravermelho e 639, 517 e 395 cm− 1 espectroscopia Raman. Baseado nos resultados encontrados, pode-se concluir que as TiO2NPs apresentam elevado grau de pureza e caráter nanomĂ©trico com formato heterogĂŞneo. Baseado em dados de literatura que relatam toxicidade em função da forma de nanopartĂculas, recomenda-se a realização recomenda-se a realização de mais estudos de toxicidade antes de seu uso em nanocompositos destinados a bioengenharia
Procedimento para avaliação da dinâmica da mastite sub- clĂnica em rebanhos bovinos utilizando planilha eletrĂ´nica do Excel ou similares de software livre.
O objetivo desta instrução tĂ©cnica Ă© apresentar uma metodologia para avaliar a dinâmica das infecções subclĂnicas em função dos dois Ăşltimos resultados de CCS (Contagem de CĂ©lulas Somáticas) de vacas em lactação. Para tal serĂŁo utilizados os dois Ăşltimos resultados de CCS de vacas individuais e funções de lĂłgica em uma planilha do Excel em PortuguĂŞs.bitstream/item/126046/1/COT-76-Proced-aval-mastite-planilha-excel.pd
Epigenome-wide analysis links SMAD3 methylation at birth to asthma in children of asthmatic mothers
Background The timing and mechanisms of asthma inception remain imprecisely defined. Although epigenetic mechanisms likely contribute to asthma pathogenesis, little is known about their role in asthma inception. Objective We sought to assess whether the trajectory to asthma begins already at birth and whether epigenetic mechanisms, specifically DNA methylation, contribute to asthma inception. Methods We used the Methylated CpG Island Recovery Assay chip to survey DNA methylation in cord blood mononuclear cells from 36 children (18 nonasthmatic and 18 asthmatic subjects by age 9 years) from the Infant Immune Study (IIS), an unselected birth cohort closely monitored for asthma for a decade. SMAD3 methylation in IIS (n = 60) and in 2 replication cohorts (the Manchester Asthma and Allergy Study [n = 30] and the Childhood Origins of Asthma Study [n = 28]) was analyzed by using bisulfite sequencing or Illumina 450K arrays. Cord blood mononuclear cell–derived IL-1β levels were measured by means of ELISA. Results Neonatal immune cells harbored 589 differentially methylated regions that distinguished IIS children who did and did not have asthma by age 9 years. In all 3 cohorts methylation in SMAD3, the most connected node within the network of asthma-associated, differentially methylated regions, was selectively increased in asthmatic children of asthmatic mothers and was associated with childhood asthma risk. Moreover, SMAD3 methylation in IIS neonates with maternal asthma was strongly and positively associated with neonatal production of IL-1β, an innate inflammatory mediator. Conclusions The trajectory to childhood asthma begins at birth and involves epigenetic modifications in immunoregulatory and proinflammatory pathways. Maternal asthma influences epigenetic mechanisms that contribute to the inception of this trajectory
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