757 resultados para Supramolecular associations
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BACKGROUND AND OBJECTIVES: Allelic variants in UMOD, the gene coding for uromodulin, are associated with rare tubulointerstitial kidney disorders and risk of CKD and hypertension in the general population. The factors associated with uromodulin excretion in the normal population remain largely unknown, and were therefore explored in this study. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Urinary uromodulin excretion was measured using a validated ELISA in two population-based cohorts that included more than 6500 individuals. The Swiss Kidney Project on Genes in Hypertension study (SKIPOGH) included 817 adults (mean age±SD, 45±17 years) who underwent renal ultrasonography and performed a 24-hour urine collection. The Cohorte Lausannoise study included 5706 adults (mean age, 53±11 years) with fresh spot morning urine samples. We calculated eGFRs using the CKD-Epidemiology Collaboration formula and by 24-hour creatinine clearance. RESULTS: In both studies, positive associations were found between uromodulin and urinary sodium, chloride, and potassium excretion and osmolality. In SKIPOGH, 24-hour uromodulin excretion (median, 41 [interquartile range, 29-57] mg/24 h) was positively associated with kidney length and volume and with creatinine excretion and urine volume. It was negatively associated with age and diabetes. Both spot uromodulin concentration and 24-hour uromodulin excretion were linearly and positively associated (multivariate analyses) with eGFR<90 ml/min per 1.73 m(2). CONCLUSION: Age, creatinine excretion, diabetes, and urinary volume are independent clinical correlates of urinary uromodulin excretion. The associations of uromodulin excretion with markers of tubular functions and kidney dimensions suggest that it may reflect tubule activity in the general population.
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Reduced glomerular filtration rate defines chronic kidney disease and is associated with cardiovascular and all-cause mortality. We conducted a meta-analysis of genome-wide association studies for estimated glomerular filtration rate (eGFR), combining data across 133,413 individuals with replication in up to 42,166 individuals. We identify 24 new and confirm 29 previously identified loci. Of these 53 loci, 19 associate with eGFR among individuals with diabetes. Using bioinformatics, we show that identified genes at eGFR loci are enriched for expression in kidney tissues and in pathways relevant for kidney development and transmembrane transporter activity, kidney structure, and regulation of glucose metabolism. Chromatin state mapping and DNase I hypersensitivity analyses across adult tissues demonstrate preferential mapping of associated variants to regulatory regions in kidney but not extra-renal tissues. These findings suggest that genetic determinants of eGFR are mediated largely through direct effects within the kidney and highlight important cell types and biological pathways.
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BACKGROUND: Risky single-occasion drinking (RSOD) is a prevalent and potentially harmful alcohol use pattern associated with increased alcohol use disorder (AUD). However, RSOD is commonly associated with a higher level of alcohol intake, and most studies have not controlled for drinking volume (DV). Thus, it is unclear whether the findings provide information about RSOD or DV. This study sought to investigate the independent and combined effects of RSOD and DV on AUD. METHODS: Data were collected in the longitudinal Cohort Study on Substance Use Risk Factors (C-SURF) among 5598 young Swiss male alcohol users in their early twenties. Assessment included DV, RSOD, and AUD at two time points. Generalized linear models for binomial distributions provided evidence regarding associations of DV, RSOD, and their interaction. RESULTS: DV, RSOD, and their interaction were significantly related to the number of AUD criteria. The slope of the interaction was steeper for non/rare RSOD than for frequent RSOD. CONCLUSIONS: RSOD appears to be a harmful pattern of drinking, associated with increased AUD and it moderated the relationship between DV and AUD. This study highlighted the importance of taking drinking patterns into account, for both research and public health planning, since RSO drinkers constitute a vulnerable subgroup for AUD.
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BACKGROUND: Alcohol consumption--in particular drinking volume (DV) and risky single occasion drinking (RSOD)--has been related to a wide range of negative consequences and health problems. Previous studies also suggested that drinking in certain locations may be more strongly associated with the occurrence of alcohol-related harm than drinking in others. However, they were conducted in countries culturally and legally different from European countries and were limited to cross-sectional designs. This study investigates the cross-sectional and longitudinal associations of alcohol-related harm with DVs in different locations in a sample of young Swiss men. METHODS: A representative sample of 4536 young Swiss male drinkers completed baseline and 15-month follow-up questionnaires. These assessed DVs in 11 locations, alcohol-related harm (i.e. number of alcohol-related consequences and alcohol use disorder criteria) and frequency of RSOD. Cross-sectional and longitudinal associations of alcohol-related harm with DVs in each location were tested using regression models, with and without adjustment for frequency of RSOD. RESULTS: Both cross-sectional and longitudinal analyses showed significant positive associations between alcohol-related harm and DVs at friends' homes, in discos/nightclubs and in outdoor public places, when controlling for frequency of RSOD. In contrast, the contribution of DVs at one's own home and in restaurants was consistently not significant when adjusted for frequency of RSOD. When controlling for RSOD, associations between alcohol-related harm and DVs in bars/pubs, when playing sports, during other leisure activities, at cinemas/theatres, during sporting events, and during special events were not consistent between cross-sectional and longitudinal analyses. CONCLUSION: Results suggest that prevention interventions should not only target reducing the overall volume of alcohol consumed and the frequency of RSOD in general, but they should additionally focus on limiting alcohol consumption in outdoor public places, discos/nightclubs, and in friends' homes in particular, or at least on preventing harm occurring in these occasions.
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Objective: Frequent Emergency Department (ED) users are vulnerable individuals and discrimination is usually associated with increased vulnerability. The aim of this study was to investigate frequent ED users' perceptions of discrimination and to test whether they were associated with increased vulnerability. Methods: In total, 250 adult frequent ED users were interviewed in Lausanne University Hospital. From a previously published questionnaire, we assessed 15 dichotomous sources of perceived discrimination. Vulnerability was assessed using health status: objective health status (evaluation by a healthcare practitioner including somatic, mental health, behavioral, and social issues - dichotomous variables) and subjective health status [self-evaluation including health-related quality of life (WHOQOL) and quality of life (EUROQOL) - mean-scores]. We computed the prevalence rates of perceived discrimination and tested associations between perceived discrimination and health status (Fischer's exact tests, Mann-Whitney U-tests)
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Gold metallogelators is an emerging area of research. The number of results published in the literature is still scarce. The majority of these gels is observed in organic solvents, and the potential applications are still to be explored. In this work, we present an overview about gold metallogelators divided in two different groups depending on the type of solvent used in the gelation process (organogelators and hydrogelators). A careful analysis of the data shows that aurophilic interactions are a common motif directly involved in gelation involving Au(I) complexes. There are also some Au(III) derivatives able to produce gels but in this case the organic ligands determine the aggregation process. A last section is included about the potential applications that have been reported until now with this new and amazing class of supramolecular assemblies.
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Mimicking Nature, supramolecular chemistry represents the chemistry beyond the molecule, in view that intermolecularinteractions constitute the driving force for the preparation of molecular and supramolecular assemblies, using the chemicalinformation contained in molecular building blocks. Upon molecular recognition between discrete units, chemical processessuch as self-assembly and self-organisation start operating, and are the leading processes to build up supramolecular aggregates and materials. When those materials have dimensions on thenanometric scale, a recently emerging scientific discipline is defined,Nanoscience. Nanomaterials are promising tools for many applications, and their use in biomedical and clinical applicationsdefines the so-called Nanomedicine. In this review we present a few selected examples of nanomaterials designed for therapeutical purposes, emphasizing the importance of the preparation methodology in terms of their therapeutical use.
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Abstract Background: Little is known about how sitting time, alone or in combination with markers of physical activity (PA), influences mental well-being and work productivity. Given the need to develop workplace PA interventions that target employees’ health related efficiency outcomes; this study examined the associations between self-reported sitting time, PA, mental well-being and work productivity in office employees. Methods: Descriptive cross-sectional study. Spanish university office employees (n = 557) completed a survey measuring socio-demographics, total and domain specific (work and travel) self-reported sitting time, PA (International Physical Activity Questionnaire short version), mental well-being (Warwick-Edinburg Mental Well-Being Scale) and work productivity (Work Limitations Questionnaire). Multivariate linear regression analyses determined associations between the main variables adjusted for gender, age, body mass index and occupation. PA levels (low, moderate and high) were introduced into the model to examine interactive associations. Results: Higher volumes of PA were related to higher mental well-being, work productivity and spending less time sitting at work, throughout the working day and travelling during the week, including the weekends (p < 0.05). Greater levels of sitting during weekends was associated with lower mental well-being (p < 0.05). Similarly, more sitting while travelling at weekends was linked to lower work productivity (p < 0.05). In highly active employees, higher sitting times on work days and occupational sitting were associated with decreased mental well-being (p < 0.05). Higher sitting times while travelling on weekend days was also linked to lower work productivity in the highly active (p < 0.05). No significant associations were observed in low active employees. Conclusions: Employees’ PA levels exerts different influences on the associations between sitting time, mental well-being and work productivity. The specific associations and the broad sweep of evidence in the current study suggest that workplace PA strategies to improve the mental well-being and productivity of all employees should focus on reducing sitting time alongside efforts to increase PA.
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Brazilian science is evolving rapidly and steadly in the last 10 years, reaching the 15º place in the international ranking. Research in nanotechnology is following a similar way generating new scientific and technological knowledge in several frontiers but specially in the interfaces of two or more areas, where Chemistry is consolidating itself as a central science. In this context, the supramolecular approach is a very promissing one because it allows the build-up of a chemical inteligence using all the sistematized knowledge for the design and development of new nanomaterials and products. The great challenge of Chemistry is not decrease the dimensionality of the materials but instead find ways to increase the dimensionality and structural complexity keeping strict control on the interactions between the components, in order to generate materials with new properties and functionalities. Unfortunately, the current vigorous advancement of scientific research has not been followed by the transformation of such know-how into patents and produts. Therefore much efforts should be devoted to build a national science and technology program, joining all the segments of the society involved in the technological development (university, institutes of technological research, industry and government) in order to promote the furtherance of the Brazilian technological base. Only in this way it is possible to evolve to a technological society capable to transform the scientific knowledge into wealthy, thus sustaining the socioeconomic development of the country.
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The purpose of this review is to describe the progress in the supramolecular chemistry of the pyrazolyl-based metal complexes. The text is written under the structural point of view, emphasizing the role of the covalent and non-covalent interactions in the rational construction of super and supramolecules.
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The interest in the chemistry of cobalt (II) tetrasulfonated phthalocyanine (PcTsCo) comes mainly from its macrocycle-ligand structure combined with their special chemical characteristics, such as high solubility, well-defined redox reactions and remarkable optical absorption in the visible region. In this work, we use layer-by-layer technique in order to assemble CoTsPc and poly(allylaminehydrochloride) (PAH) in hybrid supramolecular system. The electronic spectroscopy and cyclic voltammetry techniques were utilized to study PAH/CoTsPc multilayers growth and the cysteine catalytic oxidation. PAH/CoTsPc showed high electrochemical stability and worthwhile to mention is the remarkable influence of supramolecular arrangement on the final redox properties of the system.
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Giant extracellular hemoglobins are considered the summit of complexity in systems that carry oxygen, constituting an extraordinary model system to the study of hemoproteins. This class includes the hemoglobin of the annelid Glossoscolex paulistus that presents high cooperativity, great oligomeric and redox stabilities and ability of oligomeric reassociation. These properties have motivated evaluations about its utilization as prototype of artificial blood and biosensor. Kinetic studies involving autoxidation and detailed spectroscopic characterizations of its ferrous and ferric species have propitiated information about the structure-activity relationship of this macromolecule. The present review analyzes several biochemical issues, evaluating the state-of-art of this subject.
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1922/08/06 (A3,N95)-1922/08/12.
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1922/12/17 (A3,N114)-1922/12/23.