Sequestration of DROSHA and DGCR8 by Expanded CGG RNA Repeats Alters MicroRNA Processing in Fragile X-Associated Tremor/Ataxia Syndrome

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Highlights? DGCR8 binds to CGG RNA repeats, cause of the neurodegenerative FXTAS disease ? DGCR8 and its partner, DROSHA, are sequestered within CGG RNA aggregates ? DGCR8 rescues the neuronal cell death induced by expanded CGG RNA repeats ? MicroRNA processing is impaired in patients with FXTAS     

LPS Unmasking of Shigella flexneri Reveals Preferential Localisation of Tagged Outer Membrane Protease IcsP to Septa and New Poles

The Shigella flexneri outer membrane (OM) protease IcsP (SopA) is a member of the enterobacterial Omptin family of proteases which cleaves the polarly localised OM protein IcsA that is essential for Shigella virulence. Unlike IcsA however, the specific localisation of IcsP on the cell surface is unknown. To determine the distribution of IcsP, a haemagglutinin (HA) epitope was inserted into the non-essential IcsP OM loop 5 using Splicing by Overlap Extension (SOE) PCR, and IcsP^HA was characterised. Quantum Dot (QD) immunofluorescence (IF) surface labelling of IcsP^HA was then undertaken. Quantitative fluorescence analysis of S. flexneri 2a 2457T treated with and without tunicaymcin to deplete lipopolysaccharide (LPS) O antigen (Oag) showed that IcsP^HA was asymmetrically distributed on the surface of septating and non-septating cells, and that this distribution was masked by LPS Oag in untreated cells. Double QD IF labelling of IcsP^HA and IcsA showed that IcsP^HA preferentially localised to the new pole of non-septating cells and to the septum of septating cells. The localisation of IcsP^HA in a rough LPS S. flexneri 2457T strain (with no Oag) was also investigated and a similar distribution of IcsP^HA was observed. Complementation of the rough LPS strain with rmlD resulted in restored LPS Oag chain expression and loss of IcsP^HA detection, providing further support for LPS Oag masking of surface proteins. Our data presents for the first time the distribution for the Omptin OM protease IcsP, relative to IcsA, and the effect of LPS Oag masking on its detection.     

Health-related quality of life and weight loss among overweight and obese U.S. adults, 2001 to 2002

Objective: To examine the prevalence and association of health‐related quality of life (HRQOL) with trying to lose weight and with weight loss practices (eating fewer calories, physical activity, and both) among overweight and obese U.S. adults ≥ 20 years of age. Research Methods and Procedures: This study used data from the 2001 to 2002 National Health and Nutrition Examination Survey, a continuous annual survey of the civilian non‐institutionalized U.S. population. This analysis included those ≥ 20 years of age with BMI ≥ 25 (n = 2578) who responded to four standard HRQOL measures that assessed general health status and recent physical health, mental health, and activity limitation. Results: Among obese men, but not women, there were significant increasing linear trends in the adjusted prevalence of trying to lose weight as physically unhealthy and activity limitation days increased. Regardless of BMI or HRQOL, reducing calories was a common weight loss practice (66% to 86%). Except for recent activity limitation, respondents with BMI ≥ 35 did not generally differ by HRQOL level in the attainment of recommended physical activity either alone or in combination with reduced calories, whereas those in the BMI 25 to 34.9 groups often differed significantly by HRQOL level. Specifically, increased unhealthy or activity limitation days were associated with reduced prevalence of attained physical activity. Discussion: Our findings indicate an association between trying to lose weight and a greater number of unhealthy days reported by obese men, suggesting that these men may be influenced by traditional clinical weight‐loss counseling that is prompted by weight and comorbidity, whereas women had a high prevalence of trying to lose weight irrespective of weight and HRQOL. Assessment of HRQOL, especially measures that evaluate physical domains, could provide subjective information to assist with weight counseling.     

Genomic and signalling pathway characterization of the NZM panel of melanoma cell lines: A valuable model for studying the impact of genetic diversity in melanoma

Melanoma is a disease associated with a very high mutation burden and thus the possibility of a diverse range of oncogenic mechanisms that allow it to evade therapeutic interventions and the immune system. Here, we describe the characterization of a panel of 102 cell lines from metastatic melanomas (the NZM lines), including using whole‐exome and RNA sequencing to analyse genetic variants and gene expression changes in a subset of this panel. Lines possessing all major melanoma genotypes were identified, and hierarchical clustering of gene expression profiles revealed four broad subgroups of cell lines. Immunogenotyping identified a range of HLA haplotypes as well as expression of neoantigens and cancer–testis antigens in the lines. Together, these characteristics make the NZM panel a valuable resource for cell‐based, immunological and xenograft studies to better understand the diversity of melanoma biology and the responses of melanoma to therapeutic interventions.     

Supply- and Demand-Side Factors Influencing Utilization of Infant and Young Child Feeding Counselling Services in Viet Nam

Adequate utilization of services is critical to maximize the impact of counselling on infant and young child feeding (IYCF), but little is known about factors affecting utilization. Our study examined supply- and demand-side factors associated with the utilization of IYCF counselling services in Viet Nam. We used survey data from mothers with children <2y (n = 1,008) and health staff (n = 60) from the evaluation of a program that embedded IYCF counseling into the existing government health system. The frequency of never users, one-time users, repeat users, and achievers of the recommended minimum number of visits at health facilities were 45.1%, 13.0%, 28.4% and 13.5%, respectively. Poisson regression showed that demand-generation strategies, especially invitation cards, were the key factors determining one-time use (Prevalence ratio, PR 3.0, 95% CI: 2.2–4.2), repeated use (PR 3.2, 95% CI: 2.4–4.2), and achievement of minimum visits (PR 5.5, 95% CI: 3.6–8.4). Higher maternal education was associated with higher utilization both for one-time and repeated use. Being a farmer, belonging to an ethnic minority, and having a wasted child were associated with greater likelihood of achieving the minimum recommended number of visits, whereas child stunting or illness were not. Distance to health center was a barrier to repeated visits. Among supply-side factors, good counselling skills (PR: 1.3–1.8) was the most important factor associated with any service use, whereas longer employment duration and greater work pressure of health center staff were associated with lower utilization. Population attributable risk estimations showed that an additional 25% of the population would have achieved the minimum number of visits if exposed to three demand-generation strategies, and further increased to 49% if the health staff had good counseling skills and low work pressure. Our study provides evidence that demand-generation strategies are essential to increase utilization of facility-based IYCF counselling services in Viet Nam, and may be relevant for increasing and sustaining use of nutrition services in similar contexts.     

Concentrations of high-mobility-group proteins in the nucleus and cytoplasm of several rat tissues

Nuclear and cytoplasmic fractions were isolated from various tissues of the rat by a nonaqueous technique. The high-mobility-group (HMG) proteins were extracted from these fractions with acid and separated by one- and two-dimensional PAGE. The concentrations of high-mobility-group proteins HMG1, HMG2, and HMG17 in the nucleus and cytoplasm were then estimated from the staining intensities of the electrophoretic bands. The cytoplasmic concentrations of these proteins were very low--usually less than 1/30 of those present in the corresponding nuclear fractions. For the tissues studied (liver, kidney, heart, and lung), the concentrations of HMG proteins in the nucleus did not differ significantly from one tissue to another. Averaged over the four tissues investigated, there were 0.28 molecule of HMG1, 0.18 molecule of HMG2, and 0.46 molecule of HMG17 per nucleosome. These values are considerably higher than those that have been reported previously.     

Design and optimisation of orally active TLR7 agonists for the treatment of hepatitis C virus infection

The synthesis and structure-activity relationships of a series of novel interferon inducers are described. Pharmacokinetic studies and efficacy assessment of a series of 8-oxo-3-deazapurine analogues led to the identification of compound 33, a potent and selective agonist of the TLR7 receptor with an excellent in vivo efficacy profile in a mouse model.