194 research outputs found

    Efficient generation of mNeonGreen <i>Plasmodium falciparum</i> reporter lines enables quantitative fitness analysis

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    CRISPR editing has enabled the rapid creation of fluorescent Plasmodium transgenic lines, facilitating a deeper understanding of parasite biology. The impact of genetic perturbations such as gene disruption or the introduction of drug resistance alleles on parasite fitness is typically quantified in competitive growth assays between the query line and a wild type reference. Although fluorescent reporter lines offer a facile and frequently used method to measure relative growth, this approach is limited by the strain background of the existing reporter, which may not match the growth characteristics of the query strains, particularly if these are slower-growing field isolates. Here, we demonstrate an efficient CRISPR-based approach to generate fluorescently labelled parasite lines using mNeonGreen derived from the LanYFP protein in Branchiostoma lanceolatum, which is one of the brightest monomeric green fluorescent proteins identified. Using a positive-selection approach by insertion of an in-frame blasticidin S deaminase marker, we generated a Dd2 reporter line expressing mNeonGreen under the control of the pfpare (P. falciparum Prodrug Activation and Resistance Esterase) locus. We selected the pfpare locus as an integration site because it is highly conserved across P. falciparum strains, expressed throughout the intraerythrocytic cycle, not essential, and offers the potential for negative selection to further enrich for integrants. The mNeonGreen@pare line demonstrates strong fluorescence with a negligible fitness defect. In addition, the construct developed can serve as a tool to fluorescently tag other P. falciparum strains for in vitro experimentation

    A placebo-controlled study to investigate the effect of Dog Appeasing Pheromone and other environmental and management factors on the reports of disturbance and house soiling during the night in recently adopted puppies (Canis familiaris]

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    Disturbance and house soiling during the night are common problems faced by the new puppy dog owner. They may result as consequence of a mismatch between the developmental status of the puppy and its new environment and/or separation distress in a typically social animal. The aim of this study was to examine the effect of Dog Appeasing Pheromone (DAP, Ceva Santé Animale) as well as a range of other management and environmental factors that might affect this process. It has been suggested that DAP may help the puppy settle into the new home by continuing the provision of the maternal appeasing pheromone. In order to test this, a double-blind, placebo-controlled trial of DAP was conducted with 60 pedigree puppies, aged between 6 and 10 weeks, as they entered their new home. A few days prior to the puppy's arrival, volunteer owners were supplied with either a verum or placebo plug-in diffuser designed for the slow release of the pheromone analogue over 4 weeks. Owners reported daily on disturbance and house soiling during the previous night over the following 8 weeks from the puppy's first night in the new home. The effect of the treatment together with the gender of the puppy, its maternal environment, the use of a puppy crate, sleeping with other dogs at night and the experience of the owner were included in a general linear model to explain the total number of nights spent disturbing and house soiling. Sleeping with another dog reduced the puppies' tendency to disturb at night to almost zero. Over 70 of puppies sleeping alone disturbed during the first night. The mean total number of nights of disturbance over the 2 months was between five and six nights, mostly in the first week in the home. A significant effect of DAP treatment was found in the case of the gundog breeds only (p = 0.003), gundogs receiving placebo cried for a median of nine nights, those receiving verum cried for a median of three nights. No effect of DAP treatment was observed on the total number of nights that the puppy soiled the house (p > 0.05). However, puppies that were placed in crates during the night (p = 0.004) or had come from domestic maternal environments (p = 0.006) had significantly fewer reports of house soiling over the first 2 months in the new home. © 2006 Elsevier B.V. All rights reserved

    Gender-Related Differences in the Prevalence of Cardiovascular Disease Risk Factors and their Correlates in Urban Tanzania.

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    \ud Urban areas in Africa suffer a serious problem with dual burden of infectious diseases and emerging chronic diseases such as cardiovascular diseases (CVD) and diabetes which pose a serious threat to population health and health care resources. However in East Africa, there is limited literature in this research area. The objective of this study was to examine the prevalence of cardiovascular disease risk factors and their correlates among adults in Temeke, Dar es Salaam, Tanzania. Results of this study will help inform future research and potential preventive and therapeutic interventions against such chronic diseases. The study design was a cross sectional epidemiological study. A total of 209 participants aged between 44 and 66 years were included in the study. A structured questionnaire was used to evaluate socioeconomic and lifestyle characteristics. Blood samples were collected and analyzed to measure lipid profile and fasting glucose levels. Cardiovascular risk factors were defined using World Health Organization criteria. The age-adjusted prevalence of obesity (BMI > or = 30) was 13% and 35%, among men and women (p = 0.0003), respectively. The prevalence of abdominal obesity was 11% and 58% (p < 0.0001), and high WHR (men: >0.9, women: >0.85) was 51% and 73% (p = 0.002) for men and women respectively. Women had 4.3 times greater odds of obesity (95% CI: 1.9-10.1), 14.2-fold increased odds for abdominal adiposity (95% CI: 5.8-34.6), and 2.8 times greater odds of high waist-hip-ratio (95% CI: 1.4-5.7), compared to men. Women had more than three-fold greater odds of having metabolic syndrome (p = 0.001) compared to male counterparts, including abdominal obesity, low HDL-cholesterol, and high fasting blood glucose components. In contrast, female participants had 50% lower odds of having hypertension, compared to men (95%CI: 0.3-1.0). Among men, BMI and waist circumference were significantly correlated with blood pressure, triglycerides, total, LDL-, and HDL-cholesterol (BMI only), and fasting glucose; in contrast, only blood pressure was positively associated with BMI and waist circumference in women. The prevalence of CVD risk factors was high in this population, particularly among women. Health promotion, primary prevention, and health screening strategies are needed to reduce the burden of cardiovascular disease in Tanzania.\u

    Diagnostic criteria for cancer cachexia: Reduced food intake and inflammation predict weight loss and survival in an international, multi-cohort analysis

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    Abstract Background Cancer‐associated weight loss (WL) associates with increased mortality. International consensus suggests that WL is driven by a variable combination of reduced food intake and/or altered metabolism, the latter often represented by the inflammatory biomarker C‐reactive protein (CRP). We aggregated data from Canadian and European research studies to evaluate the associations of reduced food intake and CRP with cancer‐associated WL (primary endpoint) and overall survival (OS, secondary endpoint). Methods The data set included a total of 12,253 patients at risk for cancer‐associated WL. Patient‐reported WL history (% in 6 months) and food intake (normal, moderately, or severely reduced) were measured in all patients; CRP (mg/L) and OS were measured in N = 4960 and N = 9952 patients, respectively. All measures were from a baseline assessment. Clinical variables potentially associated with WL and overall survival (OS) including age, sex, cancer diagnosis, disease stage, and performance status were evaluated using multinomial logistic regression MLR and Cox proportional hazards models, respectively. Results Patients had a mean weight change of −7.3% (±7.1), which was categorized as: ±2.4% (stable weight; 30.4%), 2.5–5.9% (19.7%), 6.0–10.0% (23.2%), 11.0–14.9% (12.0%), ≥15.0% (14.6%). Normal food intake, moderately, and severely reduced food intake occurred in 37.9%, 42.8%, and 19.4%, respectively. In MLR, severe WL (≥15%) (vs. stable weight) was more likely (P  100 mg/L: OR 2.30 (95% CI 1.62–3.26)]. Diagnosis, stage, and performance status, but not age or sex, were significantly associated with WL. Median OS was 9.9 months (95% CI 9.5–10.3), with median follow‐up of 39.7 months (95% CI 38.8–40.6). Moderately and severely reduced food intake and CRP independently predicted OS (P < 0.0001). Conclusions Modelling WL as the dependent variable is an approach that can help to identify clinical features and biomarkers associated with WL. Here, we identify criterion values for food intake impairment and CRP that may improve the diagnosis and classification of cancer‐associated cachexia

    Structures of PI4KIIIβ complexes show simultaneous recruitment of Rab11 and its effectors

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    Phosphatidylinositol 4-kinases (PI4Ks) and small guanosine triphosphatases (GTPases) are essential for processes that require expansion and remodeling of phosphatidylinositol 4-phosphate (PI4P)-containing membranes, including cytokinesis, intracellular development of malarial pathogens, and replication of a wide range of RNA viruses. However, the structural basis for coordination of PI4K, GTPases and their effectors is unknown. Here, we describe structures of PI4KB (PI4KIIIβ) bound to the small GTPase Rab11a without and with the Rab11 effector protein FIP3. The Rab11-PI4KIIIβ interface is unique compared with known structures of Rab complexes, and does not involve switch regions used by GTPase effectors. Our data provide a mechanism for how PI4KIIIβ coordinates Rab11 and its effectors on PI4P-enriched membranes, and also provide strategies for the design of specific inhibitors that could potentially target plasmodial PI4KIIIβ to combat malaria

    Towards an asset-based approach to promoting and sustaining well-being for people with aphasia and their families: an international exploratory study

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    Background: There is growing interest in interventions that promote positive outcomes and well-being for people with aphasia (PWA) and their families, but provision is inconsistent. An asset-based approach, based on the theory of salutogenesis, focuses on what makes you well rather than ill. This approach has been used successfully across a variety of research fields, including health and social care research and practice, and has the potential to provide coherent strategies to support people living successfully with aphasia. Aim: To explore the relevance and potential of an asset-based approach to promoting and sustaining well-being for PWA and their families, across contexts and cultures. Methods & procedures: Exploratory case studies were carried out in the United Kingdom (UK), Norway, Israel, Ireland, and Denmark in a variety of settings. Following an interpretative paradigm, we used qualitative methods including: interviews; appreciative inquiry; group discussions; and participatory action research. 95 PWA and 25 family members were asked to identify assets within themselves and their communities that promote, sustain and maintain well-being, by responding to: “What makes you feel good/well/healthy?” Data were analysed using thematic analysis. Outcomes & results: An asset-based approach proved to be a powerful means for PWA and family members to explore what helps them live well with aphasia. Key themes were identified: (1) personal journey; (2) helping others; (3) connecting to self; (4) connecting to others; (5) recreation; and (6) personal attributes. Self-identification of assets, within the person and their community, and connections to these, helped PWA and their family members to maintain well-being, overcome barriers and regain confidence. Using this approach, focusing on the person’s recognition, activation and mobilisation of assets, could enhance the person’s understanding and restore meaning around the stroke and onset of aphasia. Conclusion: This novel exploratory research demonstrates the relevance and potential across diverse cultural contexts of taking an asset-based approach to promoting and sustaining well-being for PWA and their families. Focusing on maintaining connections to these assets and developing meaning around the event, could prevent some of the negative sequela of stroke. The “patient–professional” relationship must transform into a collaborative partnership, with time and flexibility needed to introduce this approach. Further research should examine how service providers and PWA could develop and operationalise an asset-based approach in clinical and community settings and identify if there is an optimum timing for introducing this approach along the stroke pathway
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