Genome-wide diversity and phylogeography of Mycobacterium avium subsp. paratuberculosis in Canadian dairy cattle

Mycobacterium avium subsp. paratuberculosis (MAP) is the causative bacterium of Johne’s disease (JD) in ruminants. The control of JD in the dairy industry is challenging, but can be improved with a better understanding of the diversity and distribution of MAP subtypes. Previously established molecular typing techniques used to differentiate MAP have not been sufficiently discriminatory and/or reliable to accurately assess the population structure. In this study, the genetic diversity of 182 MAP isolates representing all Canadian provinces was compared to the known global diversity, using single nucleotide polymorphisms identified through whole genome sequencing. MAP isolates from Canada represented a subset of the known global diversity, as there were global isolates intermingled with Canadian isolates, as well as multiple global subtypes that were not found in Canada. One Type III and six “Bison type” isolates were found in Canada as well as one Type II subtype that represented 86% of all Canadian isolates. Rarefaction estimated larger subtype richness in Québec than in other Canadian provinces using a strict definition of MAP subtypes and lower subtype richness in the Atlantic region using a relaxed definition. Significant phylogeographic clustering was observed at the inter-provincial but not at the intra-provincial level, although most major clades were found in all provinces. The large number of shared subtypes among provinces suggests that cattle movement is a major driver of MAP transmission at the herd level, which is further supported by the lack of spatial clustering on an intra-provincial scale

Modelling the regulation of telomere length: the effects of telomerase and G-quadruplex stabilising drugs

Telomeres are guanine-rich sequences at the end of chromosomes which shorten during each replication event and trigger cell cycle arrest and/or controlled death (apoptosis) when reaching a threshold length. The enzyme telomerase replenishes the ends of telomeres and thus prolongs the life span of cells, but also causes cellular immortalisation in human cancer. G-quadruplex (G4) stabilising drugs are a potential anticancer treatment which work by changing the molecular structure of telomeres to inhibit the activity of telomerase. We investigate the dynamics of telomere length in different conformational states, namely t-loops, G-quadruplex structures and those being elongated by telomerase. By formulating deterministic differential equation models we study the effects of various levels of both telomerase and concentrations of a G4-stabilising drug on the distribution of telomere lengths, and analyse how these effects evolve over large numbers of cell generations. As well as calculating numerical solutions, we use quasicontinuum methods to approximate the behaviour of the system over time, and predict the shape of the telomere length distribution. We find those telomerase and G4-concentrations where telomere length maintenance is successfully regulated. Excessively high levels of telomerase lead to continuous telomere lengthening, whereas large concentrations of the drug lead to progressive telomere erosion. Furthermore, our models predict a positively skewed distribution of telomere lengths, that is, telomeres accumulate over lengths shorter than the mean telomere length at equilibrium. Our model results for telomere length distributions of telomerase-positive cells in drug-free assays are in good agreement with the limited amount of experimental data available

Efficacy of a Non-Hypercalcemic Vitamin-D2 Derived Anti-Cancer Agent (MT19c) and Inhibition of Fatty Acid Synthesis in an Ovarian Cancer Xenograft Model

BACKGROUND:Numerous vitamin-D analogs exhibited poor response rates, high systemic toxicities and hypercalcemia in human trials to treat cancer. We identified the first non-hypercalcemic anti-cancer vitamin D analog MT19c by altering the A-ring of ergocalciferol. This study describes the therapeutic efficacy and mechanism of action of MT19c in both in vitro and in vivo models. METHODOLOGY/PRINCIPAL FINDING:Antitumor efficacy of MT19c was evaluated in ovarian cancer cell (SKOV-3) xenografts in nude mice and a syngenic rat ovarian cancer model. Serum calcium levels of MT19c or calcitriol treated animals were measured. In-silico molecular docking simulation and a cell based VDR reporter assay revealed MT19c-VDR interaction. Genomewide mRNA analysis of MT19c treated tumors identified drug targets which were verified by immunoblotting and microscopy. Quantification of cellular malonyl CoA was carried out by HPLC-MS. A binding study with PPAR-Y receptor was performed. MT19c reduced ovarian cancer growth in xenograft and syngeneic animal models without causing hypercalcemia or acute toxicity. MT19c is a weak vitamin-D receptor (VDR) antagonist that disrupted the interaction between VDR and coactivator SRC2-3. Genome-wide mRNA analysis and western blot and microscopy of MT19c treated xenograft tumors showed inhibition of fatty acid synthase (FASN) activity. MT19c reduced cellular levels of malonyl CoA in SKOV-3 cells and inhibited EGFR/phosphoinositol-3kinase (PI-3K) activity independently of PPAR-gamma protein. SIGNIFICANCE:Antitumor effects of non-hypercalcemic agent MT19c provide a new approach to the design of vitamin-D based anticancer molecules and a rationale for developing MT19c as a therapeutic agent for malignant ovarian tumors by targeting oncogenic de novo lipogenesis

Chondroitin sulfates and their binding molecules in the central nervous system

Chondroitin sulfate (CS) is the most abundant glycosaminoglycan (GAG) in the central nervous system (CNS) matrix. Its sulfation and epimerization patterns give rise to different forms of CS, which enables it to interact specifically and with a significant affinity with various signalling molecules in the matrix including growth factors, receptors and guidance molecules. These interactions control numerous biological and pathological processes, during development and in adulthood. In this review, we describe the specific interactions of different families of proteins involved in various physiological and cognitive mechanisms with CSs in CNS matrix. A better understanding of these interactions could promote a development of inhibitors to treat neurodegenerative diseases

Conceptions and Feelings of Nurses Working in Emergency Medical Services about their Professional Practice and Training Conceptos y sentimientos de enfermeros que actúan en la atención pre-hospitalaria sobre la práctica y la información profesional Concepções e sentimentos de enfermeiros que atuam no atendimento pré-hospitalar sobre a prática e a formação profissional

This descriptive study with qualitative approach aimed to identify the feelings that result from the practice and training of nurses working in mobile Emergency Medical Services (EMS). Nine nurses were interviewed in September 2007. Bardin's content analysis was used and six categories emerged: "Feelings aroused in the EMS", "Experiences in the daily routine", "nurses' activities in EMS", "Personal and professional preparedness", "Reflecting on the professional training" and "Nurses' perceptions of the EMS". The importance of this study lays in the need for personally, professionally and emotionally prepared nurses and also in the need to acknowledge and value the nursing practice in this service. The results revealed that nurses working in EMS feel secure, prepared and motivated to work and they also experience diverse feelings such as compassion, gratitude, anger, pity, sadness and anxiety. Acknowledgment and the possibility of restoring lives motivate them.<br>Este es estudio descriptivo, con abordaje cualitativo que tuvo como objetivo identificar los sentimientos resultantes de la actuación y formación de los enfermeros del servicio de atención pre-hospitalaria (APH) móvil de emergencia. Fueron entrevistados 9 enfermeros, en septiembre de 2007. Se utilizó la técnica de análisis de contenido de Bardin, que auxilió en la formación de seis categorías: "sentimientos despertados en el APH", "experiencias provenientes en el día a día del trabajo", "actividades del enfermero en el APH", "preparación personal y profesional", "reflexionando sobre la formación profesional", y, "percepción del enfermero sobre el APH". La importancia de este trabajo reside en la necesidad de contar con enfermeros con capacitación personal, profesional y emocional, también obtener el reconocimiento y valorización de la actuación de la enfermería en ese Servicio. Los resultados revelaron que los enfermeros del APH se sienten seguros, preparados y motivados para actuar, experimentan diversos sentimientos como compasión, gratitud, rabia, pena, tristeza, ansiedad, y consideran como incentivos el reconocimiento y la posibilidad de restaurar vidas.<br>Este é estudo descritivo, com abordagem qualitativa, e teve como objetivo identificar os sentimentos resultantes da atuação e formação dos enfermeiros do serviço de atendimento pré-hospitalar (APH) móvel de urgência. Foram entrevistados 9 enfermeiros, em setembro de 2007. Utilizou-se a técnica de análise de conteúdo de Bardin, que auxiliou na formação de seis categorias: "sentimentos despertados no APH", "experiências decorrentes no dia a dia do trabalho", "atividades do enfermeiro no APH", "preparo pessoal e profissional", "refletindo sobre a formação profissional" e "percepção do enfermeiro sobre o APH". A importância deste trabalho reside na necessidade de enfermeiros com capacitação pessoal, profissional e emocional, também no reconhecimento e valorização da atuação da enfermagem nesse Serviço. Os resultados revelaram que os enfermeiros do APH se sentem seguros, preparados e motivados para atuar, experimentam diversos sentimentos como compaixão, gratidão, raiva, pena, tristeza, ansiedade, e consideram como motivador o reconhecimento e a possibilidade de restaurar vidas

Repercussões da Lei Maria da Penha no enfrentamento da violência doméstica em Porto Alegre

O presente estudo procurou analisar as repercussões da Lei Maria da Penha no enfrentamento da violência domésticacontra mulheres, na cidade de Porto Alegre, a partir da visão dos profissionais que constituem a rede de atendimentoa elas. Foram entrevistados sete profissionais que atuam na rede de atendimento a mulheres vítimas de violência.Os dados sugerem que a Lei promoveu mudanças nos campos da prevenção da violência, da assistência a mulherese da punição aos agressores, com aumento da visibilidade conferida a esse fenômeno e empoderamento feminino.Conclui-se que o fortalecimento das medidas preconizadas pela Lei Maria da Penha ainda depende de investimentosna qualificação dos profissionais, de ações articuladas entre os locais de atendimento e de crescente utilização daatenção básica para a promoção da saúde de mulheres e famílias expostas à violência

BOBA FRET: Bootstrap-based analysis of single-molecule FRET data

Time-binned single-molecule Förster resonance energy transfer (smFRET) experiments with surface-tethered nucleic acids or proteins permit to follow folding and catalysis of single molecules in real-time. Due to the intrinsically low signal-to-noise ratio (SNR) in smFRET time traces, research over the past years has focused on the development of new methods to extract discrete states (conformations) from noisy data. However, limited observation time typically leads to pronounced cross-sample variability, i.e., single molecules display differences in the relative population of states and the corresponding conversion rates. Quantification of cross-sample variability is necessary to perform statistical testing in order to assess whether changes observed in response to an experimental parameter (metal ion concentration, the presence of a ligand, etc.) are significant. However, such hypothesis testing has been disregarded to date, precluding robust biological interpretation. Here, we address this problem by a bootstrap-based approach to estimate the experimental variability. Simulated time traces are presented to assess the robustness of the algorithm in conjunction with approaches commonly used in thermodynamic and kinetic analysis of time-binned smFRET data. Furthermore, a pair of functionally important sequences derived from the self-cleaving group II intron Sc.ai5γ (d3'EBS1*/IBS1*) is used as a model system. Through statistical hypothesis testing, divalent metal ions are shown to have a statistically significant effect on both thermodynamic and kinetic aspects of their interaction. The Matlab source code used for analysis (bootstrap-based analysis of smFRET data, BOBA FRET), as well as a graphical user interface, is available via http://www.aci.uzh.ch/rna/