488 research outputs found

    Chlamydial clinical isolates show subtle differences in persistence phenotypes and growth in vitro

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    Urogenital Chlamydia trachomatis infection is the most common sexually transmitted bacterial infection throughout the world. While progress has been made to better understand how type strains develop and respond to environmental stress in vitro, very few studies have examined how clinical isolates behave under similar conditions. Here, we examined the development and persistence phenotypes of several clinical isolates, to determine how similar they are to each other, and the type strain C. trachomatis D/UW-3/Cx. The type strain was shown to produce infectious progeny at a higher magnitude than each of the clinical isolates, in each of the six tested cell lines. All chlamydial strains produced the highest number of infectious progeny at 44 h post-infection in the McCoy B murine fibroblast cell line, yet showed higher levels of infectivity in the MCF-7 human epithelial cell line. The clinical isolates were shown to be more susceptible than the type strain to the effects of penicillin and iron deprivation persistence models in the MCF-7 cell line. While subtle differences between clinical isolates were observed throughout the experiments conducted, no significant differences were identified. This study reinforces the importance of examining clinical isolates when trying to relate in vitro data to clinical outcomes, as well as the importance of considering the adaptations many type strains have to being cultured in vitro.</jats:p

    Laser‐Induced Focused Ultrasound for Cavitation Treatment: Toward High‐Precision Invisible Sonic Scalpel

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138842/1/smll201701555.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/138842/2/smll201701555-sup-0001-S1.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/138842/3/smll201701555_am.pd

    Design, formulation and sensory evaluation of a polyphenol-rich food placebo: an example of aronia juice for food intervention studies

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    Products suitable for use as controls in food interventions designed to demonstrate the role of minor components are largely lacking. In the present study, we aimed to develop a formulation to be used as a placebo in a clinical trial designed to assess the effects of aronia juice polyphenols on platelet function. Three formulations with the same nutrient composition as aronia juice were prepared by mixing various nutrients, artificial colours and flavours with water. The similarity of formulations to aronia juice in terms of taste, colour, smell and texture was assessed by six food panellists. The final placebo was tested for its impact on platelet function, biochemical and anthropometric parameters in a 4-week long study. No significant changes in platelet function, or in several cardiovascular and safety markers were recorded. Formulation suitable for use as a placebo for dietary intervention studies using aronia juice has been developed and demonstrated to be well tolerated in humans

    The Terneuzen Birth Cohort. Longer exclusive breastfeeding duration is associated with leaner body mass and a healthier diet in young adulthood

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    <p>Abstract</p> <p>Background</p> <p>Breastfeeding (BF) is protective against overweight and is associated with dietary behaviour. The aims of our study were to assess the relationship between exclusive BF duration and BMI, waist circumference (WC) and waist-hip ratio (WHR) at adulthood, and to study whether dietary behaviour could explain the relationship between BF duration and the proxies of fat mass.</p> <p>Methods</p> <p>In 2004-2005, 822 subjects from the Terneuzen Birth Cohort (n = 2,604), aged 18-28 years, filled in postal questionnaires including sociodemographic factors and aspects of dietary behaviour (dietary pattern, and consumption of fruit and vegetables, snacks, sweetened beverages and alcohol); 737 subjects also underwent anthropometric measurements of weight, height, and waist and hip circumference. The relationship between exclusive BF duration and dietary outcomes was investigated by logistic regression analysis. The relationships of BF duration with the anthropometric measures were investigated by linear regression analyses. All results were corrected for age, gender and possible confounders. Finally, regression analyses were performed to investigate if diet factors had a mediating effect on the relationship between BF duration and fat mass.</p> <p>Results</p> <p>A significant inverse dose-response relationship of BF duration was found for BMI (ÎČ-0.13, SE 0.06), WC (ÎČ-0.39, SE 0.18) and WHR (ÎČ-0.003, SE 0.001), after correction for age, gender and confounders. The odds ratio (OR) of exclusive BF duration in months for a breakfast frequency of at least 5 times a week was 1.16 (95%CI 1.06-1.27), and for snack consumption of less than twice a week was 1.15 (95%CI 1.06-1.25). Both ORs were corrected for age, gender and confounders. For other dietary outcomes, the results point in the same direction, i.e. a positive relationship with BF duration, but these were not statistically significant. A mediating effect of the diet factors on the association between BF and anthropometric outcomes was not shown.</p> <p>Conclusions</p> <p>Exclusive BF duration had a significant inverse dose-response relationship with BMI, WC and WHR at young adulthood. BF duration was positively related to a healthier diet at adulthood, but this did not explain the protective effect of BF against body fat. Our results underline the recommendation of the WHO to exclusively breastfeed for 6 months or longer.</p

    Microscopic Analysis of the Tupanvirus Cycle in Vermamoeba vermiformis

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    Since Acanthamoeba polyphaga mimivirus (APMV) was identified in 2003, several other giant viruses of amoebae have been isolated, highlighting the uniqueness of this group. In this context, the tupanviruses were recently isolated from extreme environments in Brazil, presenting virions with an outstanding tailed structure and genomes containing the most complete set of translation genes of the virosphere. Unlike other giant viruses of amoebae, tupanviruses present a broad host range, being able to replicate not only in Acanthamoeba sp. but also in other amoebae, such as Vermamoeba vermiformis, a widespread, free-living organism. Although the Tupanvirus cycle in A. castellanii has been analyzed, there are no studies concerning the replication of tupanviruses in other host cells. Here, we present an in-depth microscopic study of the replication cycle of Tupanvirus in V. vermiformis. Our results reveal that Tupanvirus can enter V. vermiformis and generate new particles with similar morphology to when infecting A. castellanii cells. Tupanvirus establishes a well-delimited electron-dense viral factory in V. vermiformis, surrounded by lamellar structures, which appears different when compared with different A. castellanii cells. Moreover, viral morphogenesis occurs entirely in the host cytoplasm within the viral factory, from where complete particles, including the capsid and tail, are sprouted. Some of these particles have larger tails, which we named “supertupans.” Finally, we observed the formation of defective particles, presenting abnormalities of the tail and/or capsid. Taken together, the data presented here contribute to a better understanding of the biology of tupanviruses in previously unexplored host cells

    Victimization of patients with severe psychiatric disorders: prevalence, risk factors, protective factors and consequences for mental health. A longitudinal study

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    <p>Abstract</p> <p>Background</p> <p>Victimization among people with a Severe Mental Illness is a common phenomenon. The objectives of this study proposal are: to delineate the extent and kind of victimization in a representative sample of chronic psychiatric patients; to contribute to the development and validation of a set of instruments registering victimization of psychiatric patients; to determine risk factors and protective factors; and to gain insight into the possible consequences of victimization.</p> <p>Methods/Design</p> <p>An extensive data set of 323 patients with Sever Mental Illness (assessed 4 years ago) is used. In 2010 a second measurement will be performed, enabling longitudinal research on the predictors and consequences of victimization.</p> <p>Discussion</p> <p>The consequences of (re)victimization have barely been subjected to analysis, partially due to the lack of a comprehensive, conceptual model for victimization. This research project will contribute significantly to the scientific development of the conceptual model of victimization in chronic psychiatric patients.</p

    Combination antiretroviral therapy and the risk of myocardial infarction

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    Resolving forward-reverse logistics multi-period model using evolutionary algorithms

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    © 2016 Elsevier Ltd In the changing competitive landscape and with growing environmental awareness, reverse logistics issues have become prominent in manufacturing organizations. As a result there is an increasing focus on green aspects of the supply chain to reduce environmental impacts and ensure environmental efficiency. This is largely driven by changes made in government rules and regulations with which organizations must comply in order to successfully operate in different regions of the world. Therefore, manufacturing organizations are striving hard to implement environmentally efficient supply chains while simultaneously maximizing their profit to compete in the market. To address the issue, this research studies a forward-reverse logistics model. This paper puts forward a model of a multi-period, multi-echelon, vehicle routing, forward-reverse logistics system. The network considered in the model assumes a fixed number of suppliers, facilities, distributors, customer zones, disassembly locations, re-distributors and second customer zones. The demand levels at customer zones are assumed to be deterministic. The objective of the paper is to maximize the total expected profit and also to obtain an efficient route for the vehicle corresponding to an optimal/near optimal solution. The proposed model is resolved using Artificial Immune System (AIS) and Particle Swarm Optimization (PSO) algorithms. The findings show that for the considered model, AIS works better than the PSO. This information is important for a manufacturing organization engaged in reverse logistics programs and in running units efficiently. This paper also contributes to the limited literature on reverse logistics that considers costs and profit as well as vehicle route management

    Cold winter temperatures condition the egg-hatching dynamics of a grape disease vector

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    The leafhopper Scaphoideus titanus is the vector of a major phytoplasma grapevine disease, Flavescence dorĂ©e. The vector’s distribution is in Eastern and Northern Europe, and its population dynamics varies as a function of vineyard latitude. We tested the hypothesis that hatching dynamics are cued by cold temperatures observed in winter. We exposed eggs from a natural population to simulated “cold” and “mild” winters and varied the exposure time at 5 °C from 0 to 63 days. We show that temperature cooling mainly affected the onset of hatching and is negatively correlated to the cold time exposure. The majority of hatchings occurred more quickly in cold rather than in mild winter simulated conditions, but there was no significant difference between the duration of hatching of eggs whatever the cold time exposure. In agreement with the Northern American origin of the vector, the diapause termination and thus the timing regulation of egg hatching require cold winters
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