Smad4 regulates growth plate matrix production and chondrocyte polarity.

Smad4 is an intracellular effector of the TGFβ family that has been implicated in Myhre syndrome, a skeletal dysplasia characterized by short stature, brachydactyly and stiff joints. The TGFβ pathway also plays a critical role in the development, organization and proliferation of the growth plate, although the exact mechanisms remain unclear. Skeletal phenotypes in Myhre syndrome overlap with processes regulated by the TGFβ pathway, including organization and proliferation of the growth plate and polarity of the chondrocyte. We used in vitro and in vivo models of Smad4 deficiency in chondrocytes to test the hypothesis that deregulated TGFβ signaling leads to aberrant extracellular matrix production and loss of chondrocyte polarity. Specifically, we evaluated growth plate chondrocyte polarity in tibiae of Col2-Cre+/-;Smad4fl/fl mice and in chondrocyte pellet cultures. In vitro and in vivo, Smad4 deficiency decreased aggrecan expression and increased MMP13 expression. Smad4 deficiency disrupted the balance of cartilage matrix synthesis and degradation, even though the sequential expression of growth plate chondrocyte markers was intact. Chondrocytes in Smad4-deficient growth plates also showed evidence of polarity defects, with impaired proliferation and ability to undergo the characteristic changes in shape, size and orientation as they differentiated from resting to hypertrophic chondrocytes. Therefore, we show that Smad4 controls chondrocyte proliferation, orientation, and hypertrophy and is important in regulating the extracellular matrix composition of the growth plate

Covered metal stents in endoscopic therapy of biliary complications after liver transplantation

There is growing interest in using covered self-expandable metal stents for the treatment of benign biliary conditions, and the presence of anastomotic biliary strictures and leaks after liver transplantation provide a valuable opportunity for testing them. The performance of the stents is encouraging, and the technical success rate is high. They provide larger diameter dilation and are easily removed, and can potentially limit costs by reducing the number of procedures needed to treat anastomotic biliary strictures. However, drawbacks such as sub-optimal tolerability and migration may affect both patient management and costs. New stent designs are currently being evaluated. Randomized controlled trials and cost-effectiveness analyses comparing covered metal stents with multiple plastic stent endotherapy are warranted in order to define the role of the former as first-line or rescue treatment. (C) 2016 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.Peer reviewe

The genomic diversification of grapevine clones.

BACKGROUND:Vegetatively propagated clones accumulate somatic mutations. The purpose of this study was to better appreciate clone diversity and involved defining the nature of somatic mutations throughout the genome. Fifteen Zinfandel winegrape clone genomes were sequenced and compared to one another using a highly contiguous genome reference produced from one of the clones, Zinfandel 03. RESULTS:Though most heterozygous variants were shared, somatic mutations accumulated in individual and subsets of clones. Overall, heterozygous mutations were most frequent in intergenic space and more frequent in introns than exons. A significantly larger percentage of CpG, CHG, and CHH sites in repetitive intergenic space experienced transition mutations than in genic and non-repetitive intergenic spaces, likely because of higher levels of methylation in the region and because methylated cytosines often spontaneously deaminate. Of the minority of mutations that occurred in exons, larger proportions of these were putatively deleterious when they occurred in relatively few clones. CONCLUSIONS:These data support three major conclusions. First, repetitive intergenic space is a major driver of clone genome diversification. Second, clones accumulate putatively deleterious mutations. Third, the data suggest selection against deleterious variants in coding regions or some mechanism by which mutations are less frequent in coding than noncoding regions of the genome

pH-Controlled Liposomes for Enhanced Cell Penetration in Tumor Environment

An innovative pH-switchable colloidal system that can be exploited for site-selective anticancer drug delivery has been generated by liposome decoration with a new novel synthetic non-peptidic oligo-arginine cell-penetration enhancer (CPE) and a quenching PEGylated counterpart that detaches from the vesicle surface under the acidic conditions of tumors. The CPE module (Arg(4)-DAG) is formed by four arginine units conjugated to a first-generation (G1) 2,2-bis(hydroxymethyl)propionic acid (bis-MPA)/2,2-bis(aminomethyl)propionic acid (bis-AMPA) polyester dendron terminating with 1,2-distearoyl-3-azidopropane for liposome bilayer insertion. The zeta potential of the Arg(4)-DAG-decorated liposomes increased up to +32 mV as the Arg(4)-DAG/lipids molar ratio increased. The Arg(4)-DAG liposome shielding at pH 7.4 was provided by methoxy-PEGS(5 kDa)-polymethacryloyl sulfadimethoxine (mPEG(5) (kDa)-SDM8) with 7.1 apparent pK(a). Zeta potential, surface plasmon resonance and synchrotron small-angle X-ray scattering analyses showed that at pH 7.4 mPEG(5) (kDa)-SDM8 associates with polycationic Arg(4)-DAG-decorated liposomes yielding liposomes with neutral zeta potential. At pH 6.5, which mimics the tumor environment, mPEG(5) (kDa)-SDM8 detaches from the liposome surface yielding Arg(4)-DAG exposure. Flow cytometry and confocal microscopy showed a 30-fold higher HeLa cancer cell association of the Arg(4)-DAG-decorated liposomes compared to non-decorated liposomes. At pH 7.4, the mPEG(5) (kDa)-SDM8-coated liposomes undergo low cell association while remarkable cell association occurred at pH 6.5, which allowed for the controlled intracellular delivery of model macromolecules and small molecules loaded in the liposome under tumor conditions.Peer reviewe

Influence of Fitness on Stress Reactivity as Measured with the Trier Social Stress Test

PURPOSE: Psychosocial stress is associated with multiple health complaints which a higher cardiorespiratory fitness may reduce stress reactivity. A higher level of fitness may assist in the reduction of stress-related risk factors. Limited studies have investigated the health and cortisol response of promotoras’ (Latina community health educators) physical activity (PA) behaviors along the South Texas Mexico Border Region. The aim of this study was to assess the associations of promotoras’ fitness on stress reactivity in promotoras. METHODS: 17 promotoras’ anthropometric measures (body mass index (BMI)), were assessed before performing Trier Social Stress Test (TSST). Salivary cortisol was collected before, 10-minutes, 25-minutes, and 40-minutes post TSST via passive drool method. Self-report PA included Jurca non-exercise assessment of cardiorespiratory capacity. Promotoras also performed a 2-minute step test. All tests were assessed using Spearman correlation analyses at a significance level of .05. RESULTS: Participants’ average BMI was high (31.4±7.18 kg/m²); 76.5% were overweight or obese, 30% very or extremely obese. Physical functioning levels were low (cardiorespiratory capacity 26.0±9.1 VO2/kg/min; step test 77.4 steps/2-minutes). Salivary cortisol levels revealed significant increase at the onset of the TSST and remained significantly elevated at 10-minutes post TSST. In comparison to baseline, cortisol levels remained elevated at 25-minutes and 40-minutes post TSST. CONCLUSION: Low levels of cardiorespiratory fitness and high BMI’s may have resulted in a slower cortisol recovery time after placing the body under stress in promotoras. Regular physical activity and fitness may attenuate response to psychosocial stress and enable promotoras to achieve a healthier lifestyle

An evaluation of the Diamat HPLC analyser for simultaneous determination of haemoglobins A2 and F

The authors describe a modification of the instrumental parameters of the Diamat fully automated HPLC system for Hb A2 assay (Bio-Rad Laboratories, Milan, Italy) in order to obtain simultaneous determination of Hb A2 and Hb F

Physical Fitness and Energy Balance Activity of “Promotora” Community Health Care Workers in the South Texas-Mexico Border Region

PURPOSE: Latinas along the U.S.-Mexico border are among the most physically inactive and obese segment of the U.S. population. There is widespread recognition of the cultural appropriateness of promotoras (community health workers) in health education among Latino communities. METHODS: We conducted a cross-sectional study with 17 promotoras who reside/work in the region to investigate their physical fitness and energy balance behaviors. Promotoras completed physical testing and self-report on physical activity and dietary behaviors. Participants wore an accelerometer for one week. In addition, the validity of an activity self-report instrument to assess cardiorespiratory fitness was tested. RESULTS: Participants’ average body mass index (BMI) was high (31.4±7.18 kg/m²); 76.5% were overweight or obese, 30% very or extremely obese. Physical functioning levels were low (cardiorespiratory capacity 26.0±9.1 VO2/kg/min; step test 77.4 steps/2-minutes). Objectively measured moderate-vigorous PA (114.6 ± 87.0 minutes/week) was less than PA recommendations. Accelerometry activity significantly correlated with self-report (r = 0.71, p=0.009). Participants self-reported consuming 1889.2±492.8 kCal/day. CONCLUSION: Promotoras’ energy balance behaviors were similar to women where they reside/work. Promotoras engaging in health-promoting behaviors may enhance their effectiveness as change agents in the communities they serve

Identification of grapevine clones via high-throughput amplicon sequencing: a proof-of-concept study

Wine cultivars are available to growers in multiple clonal selections with agronomic and enological differences. Phenotypic differences between clones originated from somatic mutations that accrued over thousands of asexual propagation cycles. Genetic diversity between grape cultivars remains unexplored, and tools to discriminate unequivocally clones have been lacking. This study aimed to uncover genetic variations among a group of clonal selections of 4 important Vitis vinifera cultivars: Cabernet sauvignon, Sauvignon blanc, Chardonnay, and Merlot, and use this information to develop genetic markers to discriminate the clones of these cultivars. We sequenced with short-read sequencing technology the genomes of 18 clones, including biological replicates for a total of 46 genomes. Sequences were aligned to their respective cultivar's reference genome for variant calling. We used reference genomes of Cabernet sauvignon, Chardonnay, and Merlot and developed a de novo genome assembly of Sauvignon blanc using long-read sequencing. On average, 4 million variants were detected for each clone, with 74.2% being single nucleotide variants and 25.8% being small insertions or deletions (InDel). The frequency of these variants was consistent across all clones. From these variants, we validated 46 clonal markers using high-throughput amplicon sequencing for 77.7% of the evaluated clones, most of them small InDel. These results represent an advance in grapevine genotyping strategies and will benefit the viticulture industry for the characterization and identification of the plant material