Caractérisation et contrôle du biofilm de Vibrio tapetis, pathogène de la palourde japonaise Ruditapes philippinarum

Vibrio tapetis is a pathogenic bacterium causing the Brown Ring Disease (BRD) in Manilaclam Ruditapes philippinarum. This vibriosis is induced by bacterial adhesion on the periostracal lamina, yielding a decalcification of bivalve shell. We focused on one aspect of V tapetis pathogenicity never explored so far: biofilm formation. As in many bacterial species, pathogenesis is likely related to this microbial behavior that is the biofilm. In this study, V tapetis biofilm was characterized for the first time. The composition of the biofilm matrix was also examined. Different microcopy techniques were used to observe V tapetis biofilm, allowing us to highlight at the top of the biofilm the presence of spherical components. These peculiar components were found in biofilms of different V tapetis strains and an ultra- structure analysis indicates that there may be a physical link between these components and bacterial cells. The spherical components of V tapetis biofilm display a size and a different surface aspect than bacteria ones. Moreover, they seem to contain DNA and proteins. We also examined the effect of parameters that affect BRD prevalence and we highlighted the ability of V tapetis to persist and form biofilms in these unfavorable conditions for the disease development. Experimental study of genes potentially involved in functions related to biofilm formation was carried out by construction of a V tapetis mutant. The deletion of a quorum sensing gene (cqsA) was performed and subsequent biofilm formation was examined, revealing an exacerbated effect on the biovolume of a 24h biofilm. Finally, the antibiofilm activity of the culture supernatant of a marine bacterium, Pseudoalteromonas sp. 3}6, against V tapetis biofilm was tested, revealing the inhibition of bacterial attachment and biofilm formation. Treatment of a preformed biofilm by this supernatant also very efficient, highlighting the potential of this bacterium and its supernatant in the "anti-Vibrio" fight inaquaculture.Vibrio tapetis est une bactérie pathogène responsable de la Maladie de l'Anneau Brun(MAB) chez la palourde japonaise Ruditapes philippinarum. Cette vibriose est induite par l'adhésion du pathogène à la lame périostracale provoquant ainsi une décalcification de la coquille du bivalve. Nous nous sommes intéressés à un aspect de la pathogénicité de V tapetis encore jamais exploré jusqu'à présent : la formation de biofilm. Chez de nombreuses espèces bactériennes, la pathogénicité est étroitement liée à ce comportement microbien particulier qu'est le biofilm. Au cours de cette étude, nous avons ainsi caractérisé pour la première fois le biofilm de la souche V tapetis CECT4600. La composition de la matrice du biofilm a également été examinée. Différents types de microscopies ont été utilisés pour observer le biofilm de V tapetis, nous permettant de mettre en évidence à la surface du biofilm la présence de composants sphériques de nature inconnue. Ces composants ont été retrouvés dans les biofilms de différentes souches de V tapetis et une analyse ultra-structurelle indique qu'il pourrait y avoir un lien physique entre ces composants et les bactéries. Ces composants particuliers du biofilm de V tapetis présentent une taille et un aspect de surface différents de ceux de la bactérie et semblent également contenir de l'ADN et des protéines. L'étude de l'effet de paramètres ayant un effet sur la prévalence de MAB a été réalisée et a permis notamment de mettre en évidence la capacité de V tapetis à persister et à développer des biofilms dans ces conditions jugées défavorables à l'établissement de la maladie. L'étude expérimentale de gènes potentiellement impliqués dans des fonctions liées à la formation de biofilm a été menée par la construction d'un mutant de V tapetis. La délétion d'un gène du quorum sensing (cqsA) a été réalisée et la formation de biofilm par ce mutant a également été examinée, révélant un effet exacerbé sur le biovolume du biofilm à 24h de culture. Enfin, l'activité anti- biofilm du surnageant de culture d'une bactérie marine, Pseudoalteromonas sp. 3J6, sur le biofilm de V tapetis a été testée, révélant une inhibition de l'adhésion bactérienne et de la formation du biofilm. Le traitement d'un biofilm préformé par ce surnageant s'est révélé également très efficace, manifestant ainsi le potentiel de cette bactérie et son surnageant pour la lutte « anti-Vibrio » en aquaculture

Origin and evolution of surface spin current in topological insulators

The Dirac surface states of topological insulators offer a unique possibility for creating spin polarized charge currents due to the spin-momentum locking. Here we demonstrate that the control over the bulk and surface contribution is crucial to maximize the charge-to-spin conversion efficiency. We observe an enhancement of the spin signal due to surface-dominated spin polarization while freezing out the bulk conductivity in semiconducting Bi1.5Sb0.5Te1.7Se1.3 below 100K. Detailed measurements up to room temperature exhibit a strong reduction of the magnetoresistance signal between 2 and 100K, which we attribute to the thermal excitation of bulk carriers and to the electron-phonon coupling in the surface states. The presence and dominance of this effect up to room temperature is promising for spintronic science and technology

Relatório de estágio : a excelência do cuidado à pessoa em situação crítica

A realização deste relatório enquadra-se no âmbito do Curso Mestrado em Enfermagem, de Natureza Profissional, com Especialização em Enfermagem Médico-cirúrgica (MEEMC). O presente relatório reflete as vivências, descreve as experiências e os conhecimentos mais significativos, bem como a aquisição de competências no decurso do Estágio. O meu percurso em contexto de Estágio, decorreu em três momentos: Módulo I –Serviço de Urgência de um Hospital do Centro Hospitalar de Lisboa Norte, – Modulo II –Unidade de Cuidados Intensivos de Cirurgia Cardiotorácica de um Hospital do Centro Hospitalar de Lisboa Ocidental e – Módulo III –Bloco Operatório de um Hospital do Centro Hospitalar Tondela Viseu. O presente Relatório representa o culminar de um percurso muito diferenciado e engrandecedor no desenvolvimento de competências especializadas de natureza técnica, ética e relacional junto do Doente em estado crítico. Considero que atinge os objetivos a que me propus, nomeadamente contribuir para o meu desenvolvimento pessoal e profissional, desenvolver competências na área da Segurança do Doente, da comunicação terapêutica com o Doente e família e da qualidade de Cuidados de Enfermagem nos diversos campos de Estágio. A organização Institucional em Cuidados de Saúde, a gestão dos recursos materiais e Humanos e a organização da dinâmica das Equipas interdisciplinares representam um “Sistema maior”, que como um todo interdependente concorre para a Segurança do Doente e para a qualidade de Cuidados prestados. Cada elemento deste “Sistema maior” deve percecionar-se como uma parte fundamental desse todo. O Enfermeiro na demanda constante pela Excelência de Cuidados deve assentar a sua ação numa filosofia da segurança do Doente e da qualidade de cuidados prestados. Porquanto, deve adotar uma postura responsável, que contribua para a sedimentação da identidade da Enfermagem como uma profissão autónoma, com cariz científico e com corpo de conhecimentos próprios que retratem a consignada excelência. A atenção do Enfermeiro Especialista deve ainda ir um pouco mais além, assumindo uma postura de Modelo para com os seus pares na prestação de Cuidados. Cabe ao Enfermeiro Especialista ser impulsionador desta Filosofia no seio da sua Equipa.The writing of this report is part of the Professional Masters Course in Nursing, specializing in Medical-Surgical Nursing (MEEMC). This report reflects and describes the most relevant experiences and knowledge, as well as the acquisition of competences during the Internship. My Internship programme involved three stages: Module I – Emergency Services of a Hospital of the Centro Hospitalar de Lisboa Oriental, – Module II – Cardiothoracic Surgery Intensive Care Unit of a Hospital of the Centro Hospitalar de Lisboa Ocidental and – Module III – Operating Theatre of a Hospital of the Centro Hospitalar Tondela Viseu. This Report represents the culmination of a highly diversified and exalting experience in the development of specialized competences of a technical, ethical and relational nature with patients in a critical condition. I consider that it fulfilled the objectives I set for myself, namely to contribute towards my personal and professional development, to develop competences in the area of Patient Safety, therapeutic communication with the patient and family and the quality of Nursing Care in the different fields of Internship. Institutional organization in Healthcare, of material and human resources and of the dynamics of interdisciplinary teams represent a “Larger System”, which as an interdependent whole contributes towards Patient Safety and the quality of care provided. Each element of this “Larger System” should be understood as a fundamental part of this whole. The nurse, in the constant demand for Excellence of Care, should base his/her action on a philosophy of Patient safety and the quality of care provided. As such, s/he should adopt a responsible attitude, which will help in affirming the identity of Nursing as an autonomous profession, which is scientific in nature and with a specific body of knowledge that portrays the stipulated excellence. The attention of the Specialist Nurse should even go a bit further, assuming the posture of a model for his/her peers in the provision of Care. The Specialist Nurse has to be the driver of this Philosophy within the team

Adhesion and biofilms of Pseudomonas aeruginosa are increased under epinephrine stress

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Fulminant immune-mediated necrotising myopathy (IMNM) mimicking myocardial infarction with non-obstructive coronary arteries (MINOCA)

A 74-year-old man, with inflammatory arthritis, recently commenced on adalimumab, presented with a 4-week history of left-sided chest pain, malaise and shortness of breath. Admission ECG showed age-indeterminate left bundle branch block. Troponin T was 4444 ng/L (normal range <15 ng/L) and acute coronary syndrome treatment was commenced. Catheter angiogram revealed mild-burden non-obstructive coronary disease. Cardiac magnetic resonance (CMR) was performed to refine the differential diagnosis and demonstrated no myocardial oedema or late gadolinium enhancement. Extracardiac review highlighted oedema and enhancement of the left shoulder girdle muscles consistent with acute myositis. Creatine kinase was subsequently measured and significantly elevated at 7386 IU/L (normal range 30–200 IU/L in men). Electrophoresis clarified that this was of predominantly skeletal muscle origin. Myositis protocol MRI revealed florid skeletal muscle oedema. The MR findings, together with positive anti-Scl-70 antibodies, suggested fulminant immune-mediated necrotising myopathy presenting as a rare mimic of myocardial infarction with non-obstructive coronary arteries, diagnosed by careful extracardiac CMR review

Effects of Osmotic Stress on Rhamnolipid Synthesis and Time-Course Production of Cell-To-Cell Signal Molecules by Pseudomonas aeruginosa

Biosynthesis of biosurfactant rhamnolipids by Pseudomonas aeruginosa depends on two hierarchical quorum sensing systems, LasRI and RhlRI, which synthesize and sense the signal molecules N-(3-oxododecanoyl)-L-homoserine lactone (3OC12-HSL) and N-butyryl-L-homoserine lactone (C4-HSL), respectively. The Pseudomonas Quinolone Signal (PQS) is a third cell-to-cell signal molecule connecting these two systems, and its precursor, 2-heptyl-4-quinolone (HHQ), also constitutes a signal. The chronology of the production of signal molecules and rhamnolipids was determined during growth in PPGAS medium. Hyperosmotic condition (0.5 M NaCl) moderately affected growth, and led to intra-cellular accumulation of compatible solutes. Production of signal molecules was delayed and their highest concentrations were 2.5 to 5 fold lower than in NaCl-free PPGAS, except for HHQ, the highest concentration of which was increased. The presence of NaCl prevented rhamnolipid synthesis. When the osmoprotectant glycine betaine was added to PPGAS/NaCl medium, it was imported by the cells without being metabolized. This did not improve growth, but reestablished the time-courses of HSL and HHQ accumulation and fully or partially restored the HSL and PQS levels. It also partially restored rhamnolipid production. Quantification of mRNAs encoding enzymes involved in HSL, PQS, and rhamnolipid biosyntheses confirmed the effect of hyperosmotic stress and glycine betaine at the gene expression level

Subtipos moleculares de câncer de mama não estão associados ao subestadiamento ou ao superestadiamento do câncer de mama

Purpose to evaluate the agreement between the clinical and pathological stagings of breast cancer based on clinical and molecular features. Methods this was a cross-sectional study, in which clinical, epidemiological and pathological data were collected from 226 patients who underwent surgery at the Prof. Dr. José Aristodemo Pinotti Women's Hospital (CAISM/Unicamp) from January 2008 to September 2010. Patients were staged clinically and pathologically, and were classified as: understaged, when the clinical staging was lower than the pathological staging; correctly staged, when the clinical staging was the same as the pathological one; and overstaged, when the clinical staging was greater than the pathological staging. Results understaged patients were younger (52.2 years; p < 0.01) and more symptomatic at diagnosis (p = 0.04) when compared with correctly or overstaged patients. Clinicopathological surrogate subtype, menopausal status, parity, hormone replace therapy and histology were not associated with differences in staging. Women under 57 years of age were clinically understaged mainly due to underestimation of T ( tumor staging) (p < 0.001), as were the premenopausal women (p < 0.01). Patients whose diagnosis was made due to clinical complaints, and not by screening, were clinically understaged due to underestimation of N (lymph nodes staging) (p < 0.001). Conclusion the study shows that the clinicopathological surrogate subtype is not associated with differences in staging, while younger women diagnosed because of clinical complaints tend to have their breast tumors understaged during clinical evaluation.Objetivo avaliar a concordância entre o estadiamento clínico e patológico do câncer de mama em função das características clínicas e moleculares das pacientes. Métodos estudo de corte transversal, sendo coletados dados clínicos, epidemiológicos e anátomo-patológicos de 226 pacientes operadas no Hospital da Mulher Prof. Dr. José Aristodemo Pinotti (Centro de Atenção Integral à Saúde da Mulher - CAISM/ Unicamp), de janeiro de 2008 a setembro de 2010. As pacientes foram estadiadas clínica e patologicamente e classificadas como: subestadiadas, quando o estadiamento clínico foi menor do que o patológico; corretamente estadiadas, quando o estadiamento clínico foi equivalente ao patológico; e superestadiadas, quando o estadiamento clínico foi maior do que o patológico. Resultados as pacientes subestadiadas eram mais jovens (52,2 anos; p < 0,01) e sintomáticas ao diagnóstico (p = 0,04) do que as pacientes corretamente estadiadas ou superestadiadas. O subtipo clinico-patológico, o status menopausal, a paridade, a terapia de reposição hormonal e a histologia não foram associados com a diferença no estadiamento. Detectamos que as mulheres com menos de 57 anos de idade foram clinicamente subestadiadas principalmente devido à subestimação do T (p < 0 ,001), assim como as mulheres na pré-menopausa (p < 0,01). Por outro lado, as pacientes cujo diagnóstico foi realizado por queixa clínica, e não rastreamento, foram clinicamente subestadiadas devido à subestimação do N (p < 0,001). Conclusão o estudo nos mostra que o subtipo clinico-patológico não está associado a diferenças de estadiamento, enquanto mulheres mais jovens, e que tiveram seu diagnóstico por queixa clínica, tendem a ter seus tumores mais frequentemente subestadiados.38523924

Subtipos Moleculares De Câncer De Mama Não Estão Associados Ao Subestadiamento Ou Ao Superestadiamento Do Câncer De Mama

Purpose to evaluate the agreement between the clinical and pathological stagings of breast cancer based on clinical and molecular features. Methods this was a cross-sectional study, in which clinical, epidemiological and pathological data were collected from 226 patients who underwent surgery at the Prof. Dr. José Aristodemo Pinotti Women's Hospital (CAISM/Unicamp) from January 2008 to September 2010. Patients were staged clinically and pathologically, and were classified as: understaged, when the clinical staging was lower than the pathological staging; correctly staged, when the clinical staging was the same as the pathological one; and overstaged, when the clinical staging was greater than the pathological staging. Results understaged patients were younger (52.2 years; p &lt; 0.01) and more symptomatic at diagnosis (p = 0.04) when compared with correctly or overstaged patients. Clinicopathological surrogate subtype, menopausal status, parity, hormone replace therapy and histology were not associated with differences in staging. Women under 57 years of age were clinically understaged mainly due to underestimation of T ( tumor staging) (p &lt; 0.001), as were the premenopausal women (p &lt; 0.01). Patients whose diagnosis was made due to clinical complaints, and not by screening, were clinically understaged due to underestimation of N (lymph nodes staging) (p &lt; 0.001). Conclusion the study shows that the clinicopathological surrogate subtype is not associated with differences in staging, while younger women diagnosed because of clinical complaints tend to have their breast tumors understaged during clinical evaluation.38523924

Multiplexing strategy for simultaneous detection of redox-, phospho- and total proteome – understanding TOR regulating pathways in Chlamydomonas reinhardtii

New methods for studying the complexity of multiple PTMs in functional proteomics are required to understand cell signaling processes. In this study, a multiplexing 2DE-based approach is introduced for parallel analysis of the redox-, phospho-, and total-proteome. This triplexing approach uses spectrally distinct fluorophores, is not matrix-specific and requires relatively low sample amounts with applicability to any cell/tissue type. This methodology was applied for the study of Target of Rapamycin (TOR) regulating pathways in Chlamydomonas reinhardtii. With emerging research demonstrating a complex yet unclear relationship between TOR kinase, autophagy, and lipid metabolism, rapamycin treatment was used to induce TOR inhibition in C. reinhardtii and redox-, phospho- and total proteome changes were assessed using the triplexing approach. We identified a total of 68 spot abundance changes in response to TOR inhibition which provide a basis for understanding this highly conserved, master regulator in algae

STRESS HORMONES INCREASE BIOFILM FORMATION OF ENTEROCOCCUS FAECALIS

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