332 research outputs found

    Carvacrol ameliorates acute campylobacteriosis in a clinical murine infection model

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    Background: The prevalence of human infections with the zoonotic pathogen Campylobacter jejuni is rising worldwide. Therefore, the identification of compounds with potent anti-pathogenic and anti-inflammatory properties for future therapeutic and/or preventive application to combat campylobacteriosis is of importance for global health. Results of recent studies suggested carvacrol (4-isopropyl-2-methylphenol) as potential candidate molecule for the treatment of campylobacteriosis in humans and for the prevention of Campylobacter colonization in farm animals. Results: To address this in a clinical murine infection model of acute campylobacteriosis, secondary abiotic IL-10-/- mice were subjected to synthetic carvacrol via the drinking water starting 4 days before peroral C. jejuni challenge. Whereas at day 6 post-infection placebo treated mice suffered from acute enterocolitis, mice from the carvacrol cohort not only harbored two log orders of magnitude lower pathogen loads in their intestines, but also displayed significantly reduced disease symptoms. Alleviated campylobacteriosis following carvacrol application was accompanied by less distinct intestinal apoptosis and pro-inflammatory immune responses as well as by higher numbers of proliferating colonic epithelial cells. Remarkably, the inflammation-ameliorating effects of carvacrol treatment were not restricted to the intestinal tract, but could also be observed in extra-intestinal organs such as liver, kidneys and lungs and, strikingly, systemically as indicated by lower IFN-γ, TNF, MCP-1 and IL-6 serum concentrations in carvacrol versus placebo treated mice. Furthermore, carvacrol treatment was associated with less frequent translocation of viable C. jejuni originating from the intestines to extra-intestinal compartments. Conclusion: The lowered C. jejuni loads and alleviated symptoms observed in the here applied clinical murine model for human campylobacteriosis highlight the application of carvacrol as a promising novel option for both, the treatment of campylobacteriosis and hence, for prevention of post-infectious sequelae in humans, and for the reduction of C. jejuni colonization in the intestines of vertebrate lifestock animals

    Immunopathological properties of the Campylobacter jejuni flagellins and the adhesin CadF as assessed in a clinical murine infection model

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    Background: Campylobacter jejuni infections constitute serious threats to human health with increasing prevalences worldwide. Our knowledge regarding the molecular mechanisms underlying host-pathogen interactions is still limited. Our group has established a clinical C. jejuni infection model based on abiotic IL-10-/- mice mimicking key features of human campylobacteriosis. In order to further validate this model for unraveling pathogen-host interactions mounting in acute disease, we here surveyed the immunopathological features of the important C. jejuni virulence factors FlaA and FlaB and the major adhesin CadF (Campylobacter adhesin to fibronectin), which play a role in bacterial motility, protein secretion and adhesion, respectively. Methods and results: Therefore, abiotic IL-10-/- mice were perorally infected with C. jejuni strain 81-176 (WT) or with its isogenic flaA/B (ΔflaA/B) or cadF (ΔcadF) deletion mutants. Cultural analyses revealed that WT and ΔcadF but not ΔflaA/B bacteria stably colonized the stomach, duodenum and ileum, whereas all three strains were present in the colon at comparably high loads on day 6 post-infection. Remarkably, despite high colonic colonization densities, murine infection with the ΔflaA/B strain did not result in overt campylobacteriosis, whereas mice infected with ΔcadF or WT were suffering from acute enterocolitis at day 6 post-infection. These symptoms coincided with pronounced pro-inflammatory immune responses, not only in the intestinal tract, but also in other organs such as the liver and kidneys and were accompanied with systemic inflammatory responses as indicated by increased serum MCP-1 concentrations following C. jejuni ΔcadF or WT, but not ΔflaA/B strain infection. Conclusion: For the first time, our observations revealed that the C. jejuni flagellins A/B, but not adhesion mediated by CadF, are essential for inducing murine campylobacteriosis. Furthermore, the secondary abiotic IL-10-/- infection model has been proven suitable not only for detailed investigations of immunological aspects of campylobacteriosis, but also for differential analyses of the roles of distinct C. jejuni virulence factors in induction and progression of disease

    Campylobacter concisus Impairs Sodium Absorption in Colonic Epithelium via ENaC Dysfunction and Claudin-8 Disruption

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    The epithelial sodium channel (ENaC) can increase the colonic absorptive capacity for salt and water. Campylobacter concisus is a common pathogenic epsilonproteobacterium, causing enteritis and diarrhea. It can induce barrier dysfunction in the intestine, but its influence on intestinal transport function is still unknown. Therefore, our study aimed to characterize C. concisus effects on ENaC using the HT-29/B6-GR/MR (epithelial cell line HT-29/B6 transfected with glucocorticoid and mineralocorticoid receptors) cell model and mouse colon. In Ussing chambers, C. concisus infection inhibited ENaC-dependent Na+ transport as indicated by a reduction in amiloride-sensitive short circuit current (-55%, n = 15, p < 0.001). This occurred via down-regulation of β- and γ-ENaC mRNA expression and ENaC ubiquitination due to extracellular signal-regulated kinase (ERK)1/2 activation, predicted by Ingenuity Pathway Analysis (IPA). In parallel, C. concisus reduced the expression of the sealing tight junction (TJ) protein claudin-8 and induced claudin-8 redistribution off the TJ domain of the enterocytes, which facilitates the back leakage of Na+ ions into the intestinal lumen. In conclusion, C. concisus caused ENaC dysfunction via interleukin-32-regulated ERK1/2, as well as claudin-8-dependent barrier dysfunction-both of which contribute to Na+ malabsorption and diarrhea

    Protease Activity of Campylobacter jejuni HtrA Modulates Distinct Intestinal and Systemic Immune Responses in Infected Secondary Abiotic IL-10 Deficient Mice

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    Even though human Campylobacter jejuni infections are progressively increasing worldwide, the underlying molecular mechanisms of pathogen-host-interactions are still not fully understood. We have recently shown that the secreted serine protease HtrA plays a key role in C. jejuni cellular invasion and transepithelial migration in vitro, and is involved in the onset of intestinal pathology in murine infection models in vivo. In the present study, we investigated whether the protease activity of HtrA had an impact in C. jejuni induced acute enterocolitis. For this purpose, we perorally infected secondary abiotic IL-10−/− mice with wildtype C. jejuni strain NCTC11168 (11168WT) or isogenic bacteria carrying protease-inactive HtrA with a single point mutation at S197A in the active center (11168HtrA−S197A). Irrespective of the applied pathogenic strain, mice harbored similar C. jejuni loads in their feces and exhibited comparably severe macroscopic signs of acute enterocolitis at day 6 postinfection (p.i.). Interestingly, the 11168HtrA−S197A infected mice displayed less pronounced colonic apoptosis and immune cell responses, but enhanced epithelial proliferation as compared to the 11168WT strain infected controls. Furthermore, less distinct microscopic sequelae in 11168HtrA−S197A as compared to parental strain infected mice were accompanied by less distinct colonic secretion of pro-inflammatory cytokines such as MCP-1, IL-6, TNF, and IFN-γ in the former as compared to the latter. Strikingly, the S197A point mutation was additionally associated with less pronounced systemic pro-inflammatory immune responses as assessed in serum samples. In conclusion, HtrA is a remarkable novel virulence determinant of C. jejuni, whose protease activity is not required for intestinal colonization and establishment of disease, but aggravates campylobacteriosis by triggering apoptosis and pro-inflammatory immune responses

    Consensos em saúde bucal aprimorando a atenção básica, Ribeirão Preto, SP

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    Currently the development and use of protocols in the area of health as a tool has contributed to theOrganization and standardization of clinical practice. Model of the study: this study is to estimate qualitatively. Goal of the study: this research if proposed using the Delphi Technique to achieve a consensusamong the participants of the survey in the consolidation of the axles, concepts and categories that willcontribute to the creation and implementation of the Protocol in dental health Public health network of thecity of Ribeirão Preto. Methodology: Delphi Technique was used in the search for convergence of views.The initial sample of random character from sweepstakes between units of Health district west of Ribeirão Preto, was composed by 13 dentists and the method was described in 3 steps. Started with the Groupdental units selected, which responded to a series of questions and the results of this first phasecompiled and the summary of the results communicated again to members to reply again upon reconsideration of his replies. The end product was discussed in the workshop comprised dental practitionersinterviewed representatives of health teams, Secretary of health and of users of the service so that theinstrument could be built containing the views of all those involved in the process. Results: Showed thatthe technique Delphi favoured decision-making professionals and users about consolidation concepts,own the primary dental health for the development of dental health care, collaborating potentially forrational decisions and improving quality of care. Conclusion: Delphi technique proved effective instrument in seeking consensus on Dental public health.Atualmente, o desenvolvimento e utilização dos Protocolos clínicos e de regulação na área da saúde,como ferramenta para gestão, têm contribuído para a organização e padronização da prática clínica emdiversas áreas assistenciais, bem como conferido clareza quanto aos fluxos a serem percorridos pelospacientes, em busca do cuidado à saúde. Por meio de estudo de abordagem qualitativa e valendo-se daTécnica Delphi na busca da convergência de opiniões, objetivou-se obter um consenso entre os participantes da pesquisa para a adoção dos conceitos que pudessem subsidiar a criação e implantaçãode um Protocolo em Saúde Bucal a ser aplicado na Rede Pública de Saúde no município de RibeirãoPreto. A amostra inicial de caráter aleatório, a partir de sorteio entre as Unidades de Saúde do DistritoOeste de Ribeirão Preto foi composta por 13 dentistas e profissionais da equipe de saúde sendo que ametodologia foi desenvolvida em 3 etapas. A primeira iniciou-se com o grupo de dentistas das unidadessorteadas, que responderam a uma série de questões sendo os resultados dessa primeira fasecompilados e a síntese das tarefas reenviada aos membros para que respondessem novamente,reconsiderando as suas respostas. O produto final foi discutido em Oficina composta pelos dentistasentrevistados, representantes das equipes de saúde, da Secretaria de Saúde e dos usuários do serviçoa fim de que o instrumento pudesse ser construído contemplando o ponto de vista de todos os envolvidos no processo. Resultados: O trabalho identificou concordância final entre os participantes, pelo quese comprovou que a Técnica Delphi favoreceu a tomada de decisões dos profissionais e usuáriosacerca da consolidação de conceitos próprios da atenção básica em saúde bucal para o desenvolvimento dos cuidados nessa área, colaborando potencialmente para as decisões racionais e aprimoramento da qualidade da assistência. Mostrou-se  uma ferramenta com potência para a busca de consensos na área de Saúde Pública

    Contribuyendo a la mejora de la salud de la comunidad sorda: experiencias formativas de grado y postgrado de ciencias de la salud, desde dos orillas del Atlántico.

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    Dentro de la gran heterogeneidad que coexiste en las personas con pérdida auditiva, queremos mencionar el caso de las personas con sordera que son usuarias de las lenguas de signos autodenominadas como Comunidad Sorda . La Comunidad Sorda puede ser conceptualizada desde dos perspectivas o modelos dicotómicos: la perspectiva biomédica y la sociolinguística-cultural. Desde el modelo biomédico se conceptualiza y entiende la sordera como un déficit en la persona que debe ser "reparado", por lo tanto diagnosticarse, tratarse y rehabilitarse con el fin de que la persona devenga "normal" o sea que "hable". Para ello se aplicarán todo un conjunto de prácticas rehabilitadoras, por medio audífonos, implantes cocleares, junto con la terapia logopédica. Por otro lado el modelo sociolinguístico-cultural, el adoptado por la Comunidad Sorda, que reconoce la pérdida de audición pero no desde una vertiente patologizadora/estigmatizadora sino como peculiaridad, que hace que la persona perciba y organice el mundo a partir del rasgo visual. Desde esta perspectiva surgen conceptos como el de identidad Sorda, cultura y Comunidad Sorda, siendo la lengua de signos su rasgo identitario primordial

    Global epidemiology and clinical outcomes of carbapenem-resistant Pseudomonas aeruginosa and associated carbapenemases (POP): a prospective cohort study

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    BACKGROUND: Carbapenem-resistant Pseudomonas aeruginosa (CRPA) is a global threat, but the distribution and clinical significance of carbapenemases are unclear. The aim of this study was to define characteristics and outcomes of CRPA infections and the global frequency and clinical impact of carbapenemases harboured by CRPA. METHODS: We conducted an observational, prospective cohort study of CRPA isolated from bloodstream, respiratory, urine, or wound cultures of patients at 44 hospitals (10 countries) between Dec 1, 2018, and Nov 30, 2019. Clinical data were abstracted from health records and CRPA isolates were whole-genome sequenced. The primary outcome was 30-day mortality from the day the index culture was collected. We compared outcomes of patients with CRPA infections by infection type and across geographic regions and performed an inverse probability weighted analysis to assess the association between carbapenemase production and 30-day mortality. FINDINGS: We enrolled 972 patients (USA n=527, China n=171, south and central America n=127, Middle East n=91, Australia and Singapore n=56), of whom 581 (60%) had CRPA infections. 30-day mortality differed by infection type (bloodstream 21 [30%] of 69, respiratory 69 [19%] of 358, wound nine [14%] of 66, urine six [7%] of 88; p=0·0012) and geographical region (Middle East 15 [29%] of 52, south and central America 20 [27%] of 73, USA 60 [19%] of 308, Australia and Singapore three [11%] of 28, China seven [6%] of 120; p=0·0002). Prevalence of carbapenemase genes among CRPA isolates also varied by region (south and central America 88 [69%] of 127, Australia and Singapore 32 [57%] of 56, China 54 [32%] of 171, Middle East 27 [30%] of 91, USA ten [2%] of 527; p\u3c0·0001). KPC-2 (n=103 [49%]) and VIM-2 (n=75 [36%]) were the most common carbapenemases in 211 carbapenemase-producing isolates. After excluding USA patients, because few US isolates had carbapenemases, patients with carbapenemase-producing CRPA infections had higher 30-day mortality than those with non-carbapenemase-producing CRPA infections in both unadjusted (26 [22%] of 120 vs 19 [12%] of 153; difference 9%, 95% CI 3-16) and adjusted (difference 7%, 95% CI 1-14) analyses. INTERPRETATION: The emergence of different carbapenemases among CRPA isolates in different geographical regions and the increased mortality associated with carbapenemase-producing CRPA infections highlight the therapeutic challenges posed by these organisms. FUNDING: National Institutes of Health

    Epidemiología mundial y resultados clínicos de Pseudomonas aeruginosa resistente a carbapenemes y carbapenemasas asociadas (POP): un estudio prospectivo de cohortes

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    Antecedentes: La Pseudomonas aeruginosa resistente a los carbapenemes (CRPA) es una amenaza mundial, pero la distribución y la importancia clínica de las carbapenemasas no están claras. El objetivo de este estudio fue definir las características y los resultados de las infecciones por CRPA, así como la frecuencia global y el impacto clínico de las carbapenemasas albergadas por CRPA. Métodos: Llevamos a cabo un estudio de cohortes observacional y prospectivo de CRPA aislados de cultivos de torrente sanguíneo, respiratorio, orina o heridas de pacientes en 44 hospitales (10 países) entre el 1 de diciembre de 2018 y el 30 de noviembre de 2019. Los datos clínicos se extrajeron de los registros de salud y los aislados de CRPA se secuenciaron en todo el genoma. El resultado primario fue la mortalidad a 30 días a partir del día en que se recolectó el cultivo índice. Se compararon los resultados de los pacientes con infecciones por CRPA por tipo de infección y entre regiones geográficas y se realizó un análisis ponderado de probabilidad inversa para evaluar la asociación entre la producción de carbapenemasas y la mortalidad a 30 días. Resultados: Se incluyeron 972 pacientes (EE.UU. n=527, China n=171, América del Sur y Central n=127, Oriente Medio n=91, Australia y Singapur n=56), de los cuales 581 (60%) tenían infecciones por CRPA. La mortalidad a los 30 días difería según el tipo de infección (torrente sanguíneo 21 [30%] de 69, respiratoria 69 [19%] de 358, herida nueve [14%] de 66, orina seis [7%] de 88; p=0-0012) y la región geográfica (Oriente Medio 15 [29%] de 52, América del Sur y Central 20 [27%] de 73, EE.UU. 60 [19%] de 308, Australia y Singapur tres [11%] de 28, China siete [6%] de 120; p=0-0002). La prevalencia de genes carbapenemasa entre los aislados CRPA también varió según la región (América del Sur y Central 88 [69%] de 127, Australia y Singapur 32 [57%] de 56, China 54 [32%] de 171, Oriente Medio 27 [30%] de 91, EE.UU. diez [2%] de 527; p<0-0001). KPC-2 (n=103 [49%]) y VIM-2 (n=75 [36%]) fueron las carbapenemasas más comunes en 211 aislados productores de carbapenemasas. Después de excluir a los pacientes de EE.UU., porque pocos aislados de EE.UU. tenían carbapenemasas, los pacientes con infecciones por CRPA productoras de carbapenemasas tuvieron una mayor mortalidad a los 30 días que aquellos con infecciones por CRPA no productoras de carbapenemasas, tanto en los análisis no ajustados (26 [22%] de 120 frente a 19 [12%] de 153; diferencia 9%, IC 95% 3-16) como ajustados (diferencia 7%, IC 95% 1-14). Interpretación: La aparición de diferentes carbapenemasas entre los aislados de CRPA en diferentes regiones geográficas y el aumento de la mortalidad asociada a las infecciones por CRPA productores de carbapenemasas ponen de manifiesto los retos terapéuticos que plantean estos organismos. Financiación: Institutos Nacionales de Salud.Background: Carbapenem-resistant Pseudomonas aeruginosa (CRPA) is a global threat, but the distribution and clinical significance of carbapenemases are unclear. The aim of this study was to define characteristics and outcomes of CRPA infections and the global frequency and clinical impact of carbapenemases harboured by CRPA. Methods: We conducted an observational, prospective cohort study of CRPA isolated from bloodstream, respiratory, urine, or wound cultures of patients at 44 hospitals (10 countries) between Dec 1, 2018, and Nov 30, 2019. Clinical data were abstracted from health records and CRPA isolates were whole-genome sequenced. The primary outcome was 30-day mortality from the day the index culture was collected. We compared outcomes of patients with CRPA infections by infection type and across geographic regions and performed an inverse probability weighted analysis to assess the association between carbapenemase production and 30-day mortality. Findings: We enrolled 972 patients (USA n=527, China n=171, south and central America n=127, Middle East n=91, Australia and Singapore n=56), of whom 581 (60%) had CRPA infections. 30-day mortality differed by infection type (bloodstream 21 [30%] of 69, respiratory 69 [19%] of 358, wound nine [14%] of 66, urine six [7%] of 88; p=0·0012) and geographical region (Middle East 15 [29%] of 52, south and central America 20 [27%] of 73, USA 60 [19%] of 308, Australia and Singapore three [11%] of 28, China seven [6%] of 120; p=0·0002). Prevalence of carbapenemase genes among CRPA isolates also varied by region (south and central America 88 [69%] of 127, Australia and Singapore 32 [57%] of 56, China 54 [32%] of 171, Middle East 27 [30%] of 91, USA ten [2%] of 527; p<0·0001). KPC-2 (n=103 [49%]) and VIM-2 (n=75 [36%]) were the most common carbapenemases in 211 carbapenemase-producing isolates. After excluding USA patients, because few US isolates had carbapenemases, patients with carbapenemase-producing CRPA infections had higher 30-day mortality than those with non-carbapenemase-producing CRPA infections in both unadjusted (26 [22%] of 120 vs 19 [12%] of 153; difference 9%, 95% CI 3–16) and adjusted (difference 7%, 95% CI 1–14) analyses. Interpretation: The emergence of different carbapenemases among CRPA isolates in different geographical regions and the increased mortality associated with carbapenemase-producing CRPA infections highlight the therapeutic challenges posed by these organisms. Funding: National Institutes of Health
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