67 research outputs found
Aromatic polymers made by reductive polydehalogenation of oligocyclic monomers as conjugated polymers of intrinsic microporosity (C-PIMs)
Reductive dehalogenation polycondensation of a series of penta-or hexacyclic, bisgeminal tetrachlorides with dicobalt octacarbonyl leads to the formation of homopolymers and copolymers with very different optical spectra. While the formation of tetrabenzoheptafulvalene connectors introduces efficient conjugation barriers due to their strongly folded structure, linking of 5-membered ring-based pentacyclic building blocks via bifluorenylidene connectors allows for an extended π-conjugation along the main chain. A comparison of homopolymer P57 and copolymer P55/77 indicates a quite different reactivity for dichloromethylene functions if incorporated into 5-or 7-membered rings. Interestingly, all investigated (co)polymers show an intrinsic microporosity in the solid-state (forming so-called Conjugated Polymers of Intrinsic Microporosity C-PIMs) and have SBET values of up to 760 m2 g-1 for homopolymer P77. This value is one of the highest reported values to date for C-PIMs
Diagnosis of Non-Celiac Gluten Sensitivity (NCGS): The Salerno Experts' Criteria
Non-Celiac Gluten Sensitivity (NCGS) is a syndrome characterized by intestinal and extra-intestinal symptoms related to the ingestion of gluten-containing food, in subjects that are not affected by either celiac disease or wheat allergy. Given the lack of a NCGS biomarker, there is the need for standardizing the procedure leading to the diagnosis confirmation. In this paper we report experts’ recommendations on how the diagnostic protocol should be performed for the confirmation of NCGS. A full diagnostic procedure should assess the clinical response to the gluten-free diet (GFD) and measure the effect of a gluten challenge after a period of treatment with the GFD. The clinical evaluation is performed using a self-administered instrument incorporating a modified version of the Gastrointestinal Symptom Rating Scale. The patient identifies one to three main symptoms that are quantitatively assessed using a Numerical Rating Scale with a score ranging from 1 to 10. The double-blind placebo-controlled gluten challenge (8 g/day) includes a one-week challenge followed by a one-week washout of strict GFD and by the crossover to the second one-week challenge. The vehicle should contain cooked, homogeneously distributed gluten. At least a variation of 30% of one to three main symptoms between the gluten and the placebo challenge should be detected to discriminate a positive from a negative result. The guidelines provided in this paper will help the clinician to reach a firm and positive diagnosis of NCGS and facilitate the comparisons of different studies, if adopted internationally
Diagnosis of Non-Celiac Gluten Sensitivity (NCGS)
Non-Celiac Gluten Sensitivity (NCGS) is a syndrome characterized by intestinal
and extra-intestinal symptoms related to the ingestion of gluten-containing
food, in subjects that are not affected by either celiac disease or wheat
allergy. Given the lack of a NCGS biomarker, there is the need for
standardizing the procedure leading to the diagnosis confirmation. In this
paper we report experts’ recommendations on how the diagnostic protocol should
be performed for the confirmation of NCGS. A full diagnostic procedure should
assess the clinical response to the gluten-free diet (GFD) and measure the
effect of a gluten challenge after a period of treatment with the GFD. The
clinical evaluation is performed using a self-administered instrument
incorporating a modified version of the Gastrointestinal Symptom Rating Scale.
The patient identifies one to three main symptoms that are quantitatively
assessed using a Numerical Rating Scale with a score ranging from 1 to 10. The
double-blind placebo-controlled gluten challenge (8 g/day) includes a one-week
challenge followed by a one-week washout of strict GFD and by the crossover to
the second one-week challenge. The vehicle should contain cooked,
homogeneously distributed gluten. At least a variation of 30% of one to three
main symptoms between the gluten and the placebo challenge should be detected
to discriminate a positive from a negative result. The guidelines provided in
this paper will help the clinician to reach a firm and positive diagnosis of
NCGS and facilitate the comparisons of different studies, if adopted
internationally
Self-Concept and Physical Activity: Differences Between High School and University Students in Spain and Portugal
The period of adolescence stands out as a critical and decisive phase, first because it leaves its mark on personality development, which is affected by psychosocial factors, and second because the healthy lifestyle habits acquired during this stage form a foundation for adulthood. The objective of the present study was first to evaluate the levels of participation in physical activities (PA) and of self-concept in high school and university students, and second to find relationships between these psycho-physical variables. Four hundred and forty adolescents ranging in age from 16 to 20 years, from Spain and Portugal, participated in this study (cross-sectional design). The IPAQ and Self-Concept Form-5 questionnaires were used. The results demonstrated some differences; the Portuguese university students had lower scores in the academic, emotional and physical dimensions and vigorous PA but higher sitting time, walking and moderate PA compared to Portuguese high school students. In addition, Spanish university students had lower self-concept scores although higher practice of PA and lower sitting time than Spanish high school students (p < 0.05). On the other hand, a positive relationship was found between different dimensions of self-concept and levels of PA, while the relationship between these dimensions and the time the adolescent spent sitting was negative. In conclusion, the university students have lower scores of self-concept dimensions (in general), and the practice of PA is higher in Spanish university students, confirming the clear presence of differences between both educational stages. The relationship between the dimensions of self-concept in general and the level of PA was positive (following the contributions of Marsh)
Strong mucosal immune responses in SIV infected macaques contribute to viral control and preserved CD4+ T-cell levels in blood and mucosal tissues
<p>Abstract</p> <p>Background</p> <p>Since there is still no protective HIV vaccine available, better insights into immune mechanism of persons effectively controlling HIV replication in the absence of any therapy should contribute to improve further vaccine designs. However, little is known about the mucosal immune response of this small unique group of patients. Using the SIV-macaque-model for AIDS, we had the rare opportunity to analyze 14 SIV-infected rhesus macaques durably controlling viral replication (controllers). We investigated the virological and immunological profile of blood and three different mucosal tissues and compared their data to those of uninfected and animals progressing to AIDS-like disease (progressors).</p> <p>Results</p> <p>Lymphocytes from blood, bronchoalveolar lavage (BAL), and duodenal and colonic biopsies were phenotypically characterized by polychromatic flow cytometry. In controllers, we observed higher levels of CD4+, CD4+CCR5+ and Gag-specific CD8+ T-cells as well as lower immune activation in blood and all mucosal sites compared to progressors. However, we could also demonstrate that immunological changes are distinct between these three mucosal sites.</p> <p>Intracellular cytokine staining demonstrated a significantly higher systemic and mucosal CD8+ Gag-specific cellular immune response in controllers than in progressors. Most remarkable was the polyfunctional cytokine profile of CD8+ lymphocytes in BAL of controllers, which significantly dominated over their blood response. The overall suppression of viral replication in the controllers was confirmed by almost no detectable viral RNA in blood and all mucosal tissues investigated.</p> <p>Conclusion</p> <p>A strong and complex virus-specific CD8+ T-cell response in blood and especially in mucosal tissue of SIV-infected macaques was associated with low immune activation and an efficient suppression of viral replication. This likely afforded a repopulation of CD4+ T-cells in different mucosal compartments to almost normal levels. We conclude, that a robust SIV-specific mucosal immune response seems to be essential for establishing and maintaining the controller status and consequently for long-term survival.</p
Spectrum of gluten-related disorders: consensus on new nomenclature and classification
A decade ago celiac disease was considered extremely rare outside Europe and, therefore, was almost completely ignored by health care professionals. In only 10 years, key milestones have moved celiac disease from obscurity into the popular spotlight worldwide. Now we are observing another interesting phenomenon that is generating great confusion among health care professionals. The number of individuals embracing a gluten-free diet (GFD) appears much higher than the projected number of celiac disease patients, fueling a global market of gluten-free products approaching $2.5 billion (US) in global sales in 2010. This trend is supported by the notion that, along with celiac disease, other conditions related to the ingestion of gluten have emerged as health care concerns. This review will summarize our current knowledge about the three main forms of gluten reactions: allergic (wheat allergy), autoimmune (celiac disease, dermatitis herpetiformis and gluten ataxia) and possibly immune-mediated (gluten sensitivity), and also outline pathogenic, clinical and epidemiological differences and propose new nomenclature and classifications
Ligand-dependent tumor induction in medakafish embryos by a Xmrk receptor tyrosine kinase transgene
Xmrk encodes a subclass 1 receptor tyrosine kinase (RTK) which has been cloned from the melanomainducing locus Tu of the poeciliid fish Xiphophorus. To demonstrate a high oncogenic potential in vivo we transferred the gene into early embryos of the closely related medakafish. Ectopic expression of the Xmrk oncogene under the control of a strong, constitutive promoter (CMVTk) led to the induction of embryonic tumors with high incidence, after short latency periods, and with a specific pattern of affected tissues. We demonstrate ligand-dependent transformation in vivo using a chimeric receptor consisting of the extracellular and transmembrane domains of the human EGF receptor (HER) and the cytoplasmatic domain of Xmrk. Expression of the chimeric receptor alone does not lead to ldnase activation or induction of tumors. Coexpression of the chimera with its corresponding ligand, human transforming growth factor alpha (bTGF(X), however, results in the activation of the chimeric RTK. In injected fish embryos the induction of the neoplastic growth is observed with similar incidence and tissue distribution as in embryos carrying the native Xmrk oncogene suggesting that the ligand as well as factors downstream of tbe RTK are required for tumor formation. In this study we show single-step induction of tumors by ectopic expression of RTKs in vivo substantiating tbe significance of autocrine stimulation in RTK induced tumors in vertebrales
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