618 research outputs found

    Polymorphic Behavior of Copolymers of Syndiotactic Polystyrene with m-Methylstyrene.

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    The influence of the presence of different amounts m-methylstyrene (m-MS), in the composition range 4−21 mol %, on the polymorphic behavior of syndiotactic polystyrene (s-PS) is presented. A comparison with the effect of the presence of p-methylstyrene is also presented. The behavior of copolymers subjected to solvent extraction or annealing procedures indicates that the presence of m-MS stabilizes the γ form of s-PS, which remains stable in a large temperature range, up to 210−220 °C. The helical mesoporous δ form of s-PS has not been observed in copolymers with m-MS. The presence of low contents of m-MS induces crystallization of the β form from polymer solution (by casting at high temperatures), whereas high concentrations of m-MS tend to stabilize the γ form. The copolymer samples crystallize from the melt in α and β forms depending on the concentration of m-MS, which stabilizes the β form for composition around 11 mol %, and induces crystallization in the α form for lower (4 mol %) and higher (21 mol %) concentration. Moreover, even when the memory of the α form is maintained in the melt, the presence of m-MS in a concentration around 11 mol % induces the crystallization of the β form, whereas, even though no memory of the α form is present in the melt, samples with 4 and 21 mol % of m-MS crystallize in the α form. The α form obtained in these copolymers, by melt-crystallization or annealing of the γ form, does not correspond to neither the disordered α‘, nor the ordered α‘ ‘ modifications observed in s-PS. The presence of m-MS comonomeric units induces structural variation in the crystal packing of the trans-planar chains, and a new crystalline form is obtained

    Gene expression in mdx mouse muscle in relation to age and exercise: aberrant mechanical-metabolic coupling and implications for pre-clinical studies in duchenne muscular dystrophy

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    Weakness and fatigability are typical features of Duchenne muscular dystrophy patients and are aggravated in dystrophic mdx mice by chronic treadmill exercise. Mechanical activity modulates gene expression and muscle plasticity. Here, we investigated the outcome of 4 (T4, 8 weeks of age) and 12 (T12, 16 weeks of age) weeks of either exercise or cage-based activity on a large set of genes in the gastrocnemius muscle of mdx and wild-type (WT) mice using quantitative real-time PCR. Basal expression of the exercise-sensitive genes peroxisome-proliferator receptor γ coactivator 1α (Pgc-1α) and Sirtuin1 (Sirt1) was higher in mdx versus WT mice at both ages. Exercise increased Pgc-1α expression in WT mice; Pgc-1α was downregulated by T12 exercise in mdx muscles, along with Sirt1, Pparγ and the autophagy marker Bnip3. Sixteen weeks old mdx mice showed a basal overexpression of the slow Mhc1 isoform and Serca2; T12 exercise fully contrasted this basal adaptation as well as the high expression of follistatin and myogenin. Conversely, T12 exercise was ineffective in WT mice. Damage-related genes such as gp91-phox (NADPH-oxidase2), Tgfβ, Tnfα and c-Src tyrosine kinase were overexpressed in mdx muscles and not affected by exercise. Likewise, the anti-inflammatory adiponectin was lower in T12-exercised mdx muscles. Chronic exercise with minor adaptive effects in WT muscles leads to maladaptation in mdx muscles with a disequilibrium between protective and damaging signals. Increased understanding of the pathways involved in the altered mechanical-metabolic coupling may help guide appropriate physical therapies while better addressing pharmacological interventions in translational researchWeakness and fatigability are typical features of Duchenne muscular dystrophy patients and are aggravated in dystrophic mdx mice by chronic treadmill exercise. Mechanical activity modulates gene expression and muscle plasticity. Here, we investigated the outcome of 4 (T4, 8 weeks of age) and 12 (T12, 16 weeks of age) weeks of either exercise or cage-based activity on a large set of genes in the gastrocnemius muscle of mdx and wildtype (WT) mice using quantitative real-time PCR. Basal expression of the exercise-sensitive genes peroxisome-proliferator receptor g coactivator 1α (Pgc-1α) and Sirtuin1 (Sirt1) was higher in mdx versus WT mice at both ages. Exercise increased Pgc-1α expression in WT mice; Pgc-1α was downregulted by T12 exercise in mdx muscles, along with Sirt1, Pparγ and the autophagy marker Bnip3. Sixteen weeks old mdx mice showed a basal over expression of the slowMhc1 isoform and Serca2; T12 exercise fully contrasted this basal adaptation as well as the high expression of follistatin and myogenin. Conversely, T12 exercise was ineffective in WT mice. Damage-related genes such as gp91-phox (NADPH-oxidase2), Tgfβ, Tnfα and c-Src tyrosine kinase were overexpressed in mdx muscles and not affected by exercise. Likewise, the anti-inflammatory adiponectin was lower in T12-exercised mdx muscles. Chronic exercise with minor adaptive effects in WT muscles leads to maladaptation in mdx muscles with a disequilibrium between protective and damaging signals. Increased understanding of the pathways involved in the altered mechanical-metabolic coupling may help guide appropriate physical therapies while better addressing pharmacological interventions in translational research

    Characterization of hematite nanowire arrays synthesized by atmospheric plasma.

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    Hematite synthesized by low pressure oxygen plasma has been shown previously to exhibit promising characteristics as a photo-anode for a photoelectrochemical water splitting cell. It is cheap, stable and has a 2.1 eV bandgap and exhibits a significant photoactivity due to the presence of a thin interfacial layer and oxygen vacancy planes throughout the sample. Unfortunately, due to the nature of vacuum systems, this process would be difficult to scale-up and as such atmospheric plasma synthesis was explored. Photoactive hematite nanowire arrays were synthesized using an atmospheric microwave plasma jet reactor. They exhibited all of the characteristics of those synthesized under low pressure except for poor photoactivity due to a thin amorphous oxide layer on the surface layer. This oxide layer was removed by hydrofluoric acid etching and subsequently produced a significant photoactivity. Further synthesis improvements have yielded hematite nanowire arrays with no amorphous oxide layer present. Removal of nanowires from the nanowire array decreased the subsequent photoactivity of the electrode, indicating that photoactivity is due to the nanowires present on the sample and not due to the thin interfacial layer. Testing at different light intensities under constant voltage shows that photoactivity of hematite nanowire arrays is linearly dependent on light intensity

    Association between Mediterranean diet and hand grip strength in older adult women

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    BACKGROUND & AIMS: Mediterranean Diet (MD) is an eating pattern associated with multiple healthy benefits, including the conservation of skeletal muscle. Frailty is a major geriatric syndrome characterized by low muscle strength. The Hand Grip Strength (HGS) is the most frequently used indicator of muscle functional capacity for clinical purposes. The association between the adherence to the MD and HGS in elderly has not yet fully investigated. The goal of this study was to examine the association between the adherence to the MD and HGS in a not hospitalized elderly who participated in the project PERsonalised ict Supported Services for Independent Living and Active Ageing (PERSSILAA). METHODS: Eighty-four elderly women were consecutively enrolled (aged 60-85 years) in this cross-sectional observational study. Anthropometric measures were evaluated. A validated 14-item questionnaire PREDIMED (PREvención con DIeta MEDiterránea) was used for the assessment of adherence to the MD. Dietary data were collected by a 7-day food records. Muscle strength was measured by HGS using a grip strength dynamometer (KERN & SOHN GmbH). RESULTS: The majority of participants were overweight (46.4%). An average adherence to the MD was found in 52.4% of participants, while the minority of them showed a low adherence (21.4%). HGS > cut-point of 20 kg were found in 43 subjects (51.2%). According to the adherence to MD, 39% participants with HGS values higher than cut-point presented a high adherence score compared with 14% of those with lower values of HGS (p = 0.018). The participants with HGS > cut-point presented significantly higher PREDIMED score than those with HGS < cut-point (p < 0.001). Based on ROC curves, the most sensitive and specific cut-point for the PREDIMED score to predict HGS categories was ≥8. No evident correlations were observed between HGS and age, while HGS was negatively correlated with hip circumference (r = -0.233, p = 0.033) and BMI (r = -0.219, p = 0.045), and positively correlated with PREDIMED score (r = 0.598, p < 0.001). At binomial logistic regression analysis almost all 14-items of PREDIMED questionnaire were significantly associated with HGS adjusted for BMI. At multinomial logistic regression analysis to assess the association of the three classes of adherence to the MD with the HGS, after adjusting for BMI the lowest adherence to MD was associated with the lowest Odds Ratio of HGS (p < 0.001). CONCLUSIONS: This study evidenced a positive association between the adherence to the MD and muscle strength in a sample of active elderly women, stratified according to the HGS > cut-point of 20 kg. Our study highlights the usefulness of the developing health services to detect and prevent age-associated decline in physical performance in elderly subjects by addressing nutritional and physical intervention

    Modulation of tryptophan/serotonin pathway by probiotic supplementation in human immunodeficiency virus-positive patients: preliminary results of a new study approach

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    Background: To date, no data are available regarding the effects of probiotics on the pathway of tryptophan/serotonin metabolism among human immunodeficiency virus (HIV) 1–infected individuals. Because a condition of dysbiosis might be responsible for the altered use of tryptophan described in this population, the aim of this study was to investigate the link between probiotic supplementation and serotonin levels in combined antiretroviral therapy–treated patients and the subsistence of an interplay with inflammation. Methods: We conducted a pilot study that included 8 HIV-positive subjects. We collected blood and fecal samples before and after 6 months of probiotic supplementation, to measure the level of serotonin in serum and tryptophan in stool, the expression of CD38 and HLADR on peripheral CD4+ T lymphocytes (as immune activation markers), the expression of indoleamine 2,3-dioxygenase 1 messenger RNA (mRNA) and IFN-γ mRNA (as markers of tryptophan metabolism and systemic inflammation). Results: After probiotic supplementation, we observed a significant increase in concentration of serum serotonin (P=.008) and a decreased level of tryptophan in plasma. Moreover, a significant reduction in CD38 and HLA-DR expression on the surface of peripheral CD4+ T cells (P=.008) and a reduced expression of indoleamine 2,3-dioxygenase 1 mRNA on peripheral blood mononuclear cells (P=.04) were observed. Conclusions: Considering that this probiotic (Vivomixx® in EU; Visbiome® in USA) has an influence on tryptophan metabolism, larger studies on this topic are needed

    Advances in the Management of Medullary Thyroid Carcinoma. Focus on Peptide Receptor Radionuclide Therapy

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    Effective treatment options in advanced/progressive/metastatic medullary thyroid carcinoma (MTC) are currently limited. As in other neuroendocrine neoplasms (NENs), peptide receptor radionuclide therapy (PRRT) has been used as a therapeutic option in MTC. To date, however, there are no published reviews dealing with PRRT approaches. We performed an in-depth narrative review on the studies published in this field and collected information on registered clinical trials related to this topic. We identified 19 published studies, collectively involving more than 200 patients with MTC, and four registered clinical trials. Most cases of MTC were treated with PRRT with somatostatin analogues (SSAs) radiolabelled with 90 yttrium (90Y) and 177 lutetium (177Lu). These radiopharmaceuticals show efficacy in the treatment of patients with MTC, with a favourable radiological response (stable disease, partial response or complete response) in more than 60% of cases, coupled with low toxicity. As MTC specifically also expresses cholecystokinin receptors (CCK2Rs), PRRT with this target has also been tried, and some randomised trials are ongoing. Overall, PRRT seems to have an effective role and might be considered in the therapeutic strategy of advanced/progressive/metastatic MTC

    Data on protein abundance alteration induced by chronic exercise in mdx mice model of Duchenne muscular dystrophy and potential modulation by apocynin and taurine

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    Here we present original data related to the research paper entitled “Proteome analysis in dystrophic mdx mouse muscle reveals a drastic alteration of Key Metabolic and Contractile Proteins after chronic exercise and the potential modulation by anti-oxidant compounds” (Gamberi et al., 2018) [1]. The dystrophin-deficient mdx mouse is the most common animal model for Duchenne muscular dystrophy. The mdx mice phenotype of the disorder is milder than in human sufferers and it can be worsened by chronic treadmill exercise. Apocynin and taurine are two antioxidant compounds proved to be beneficial on some pathology related parameters (Schröder and Schoser, 2009) [2]. This article reports the detailed proteomic data on protein abundance alterations, in tibialis anterior muscle of mdx mice, induced by chronic exercise protocol. A selected group of mdx mice was also treated with apocynin and taurine during this protocol. Detailed MS data, comparison between mdx vs wild type, exercised mdx vs wild type, and complete analysis of spot variation are provided. Furthermore, in wild type mice subjected to the same exercise protocol, the abundance of key proteins, resulted modified in exercised mdx, were analyzed by western blot

    Patient satisfaction with calcipotriol/betamethasone dipropionate cutaneous foam for the treatment of plaque psoriasis: The LION real-life multicenter prospective observational cohort study

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    Topical treatment is the mainstay for mild or moderate psoriasis, but patients are generally little satisfied. Calcipotriol/betamethasone dipropionate (Cal/BD) cutaneous foam has shown to improve signs and symptoms in plaque psoriasis patients. This study assessed patient's satisfaction with Cal/BD foam in a real-life Italian dermatological clinical practice. A multicenter, 4-week observational prospective cohort study enrolled, in 17 Italian dermatology clinics, adult patients with plaque psoriasis on the body and/or scalp. Treatment satisfaction was assessed by 9-item Treatment Satisfaction Questionnaire for Medication (TSQM-9), preference over previous treatments by Patient Preference Questionnaire (PPQ), and change in disease state by Psoriasis Area Severity Index (PASI). Overall 256 patients were eligible, with a mean (SD) age of 55.6 (15.4) years, 59.4% were males. Psoriasis severity was mild in 52.0% of patients, moderate in 43.3%, and severe in 4.7%. Scalp involvement was present in 36.7% of patients. Previous antipsoriatic treatments had been received by 80.5% of patients. TSQM-9 median (25th-75th percentile) scores were 83.3 (66.7-88.9) for effectiveness, 77.8 (66.7-88.9) for convenience, and 78.6 (64.3-92.9) for global satisfaction. Mean (SD) PASI value decreased from 7.3 (4.8) to 2.1 (2.7) after 4 weeks. More than 90% of patients previously treated for psoriasis evaluated the Cal/BD foam more effective, easier to use and better tolerated compared to previous topical treatments at PPQ. This observational study provides real-life evidence of a high level of satisfaction with effectiveness and convenience of the Cal/BD foam in a cohort of plaque psoriasis patients, with an objective improvement in PASI

    Organs on chip approach: A tool to evaluate cancer-immune cells interactions

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    In this paper we discuss the applicability of numerical descriptors and statistical physics concepts to characterize complex biological systems observed at microscopic level through organ on chip approach. To this end, we employ data collected on a micro uidic platform in which leukocytes can move through suitably built channels toward their target. Leukocyte behavior is recorded by standard time lapse imaging. In particular, we analyze three groups of human peripheral blood mononuclear cells (PBMC): heterozygous mutants (in which only one copy of the FPR1 gene is normal), homozygous mutants (in which both alleles encoding FPR1 are loss-of-function variants) and cells from ‘wild type’ donors (with normal expression of FPR1). We characterize the migration of these cells providing a quantitative con rmation of the essential role of FPR1 in cancer chemotherapy response. Indeed wild type PBMC perform biased random walks toward chemotherapy-treated cancer cells establishing persistent interactions with them. Conversely, heterozygous mutants present a weaker bias in their motion and homozygous mutants perform rather uncorrelated random walks, both failing to engage with their targets. We next focus on wild type cells and study the interactions of leukocytes with cancerous cells developing a novel heuristic procedure, inspired by Lyapunov stability in dynamical systems
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