305 research outputs found
CONSTRUCTING INEQUALITY IN THREE KENTUCKY COMMUNITIES: DISCOURSES OF BLAME AND RESPONSIBILTY
This thesis focuses on the social determinants of health in Appalachia. Using anthropological ethnographic field methods, this thesis explores the ways in which public assistance programs and exchanges between health care practitioners and clients result in discourses of blame and responsibly. Also included is a discussion of the role that health insurance plays in granting or denying individuals living in poverty the opportunity for treatment and care. The narratives collected for this project then become the bases for a critical examination of the public discourse surrounding health care reform in the United States in 2009 and 2010
Promises and Pitfalls of Metal Imaging in Biology
A picture may speak a thousand words, but if those words fail to form a coherent sentence there is little to be learned. As cutting-edge imaging technology now provides us the tools to decipher the multitude of roles played by metals and metalloids in molecular, cellular and developmental biology, as well as health and disease, it is time to reflect on the advances made in imaging, the limitations discovered, and the future of a burgeoning field. In this Perspective, the current state-of-the-art is discussed from a self-imposed contrarian position, as we not only highlight the major advances made of the years but use them as teachable moments to zoom in on challenges that remain to be overcome. We also describe the steps being taken towards being able to paint a completely undisturbed picture of cellular metal metabolism, which is, metaphorically speaking, the Holy Grail of the discipline
Fluorescent probes for the simultaneous detection of multiple analytes in biology
This review identifies and discusses fluorescent sensors that are capable of simultaneously reporting on the presence of two analytes for biological application.</p
STUDENT ENGAGEMENT THROUGH DATA MAPPING IN AN UNDERGRADUATE ENVIRONMENTAL CHEMISTRY LABORATORY
We are all too familiar with the map visualisations in media depicting the spread and severity of COVID-19 across the world. The representation of statistical data on a map is a powerful tool that can effectively convey factors such as magnitude, density and spatial variations. Analysing data in this format can help identify trends (eg âhotspotsâ, âpatient zeroâ) from large datasets. Whilst students outside the discipline of geosciences may be familiar with analysing a data map; constructing one would be a rare experience.
In our undergraduate environmental chemistry laboratory, students analyse the metal ion content and hardness of water samples collected on campus. We have used Google Maps Application Programming Interface (API)1 to allow students to geotag their results on a Google Map. The resulting bubble map is live and continually updated as students complete the lab and submit their results.2 This map is shared with the cohort so students can view the evolution of data, their contribution to the âprojectâ and generate their own hypotheses as to why certain concentrations may be linked to certain locales (eg. age of building). This approach offers rich context-based learning that could be modified to address other datasets/contexts, locations, and disciplines
A cobalt(II) complex with unique paraSHIFT responses to anions
A cobalt(ii) complex can distinguish between anions by observing the paramagnetic 1H NMR shift.</p
Mechanisms of cell uptake and toxicity of the anticancer drug cisplatin
Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugÀnglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.Two major issues which hamper the use of the anticancer drug cisplatin are the development of cancer cell resistance and its nephrotoxicity. One possible mechanism by which resistance is reported to develop is a reduction in drug uptake across the cell membrane. While the passive uptake of cisplatin has long been cited as an important contribution, far greater attention has been given to active modes of uptake, particularly in recent research. Using unilamellar lipid vesicles together with the stopped-flow kinetic method we show here that the permeability coefficient of cisplatin increases significantly with the chloride concentration of the medium. This supports the hypothesis that cisplatin can enter cells via passive permeation through the lipid phase of the membrane, but becomes trapped within the cytoplasm because dissociation of chloride ligands yields a membrane-impermeant positively-charged aqua derivative. This is important evidence for a major role of passive membrane diffusion in the uptake of cisplatin, and suggests that reduced cell uptake is unlikely to be a significant mechanism leading to the development of drug resistance. Studies of rubidium ion uptake into the cytoplasm of Xenopus oocytes via the Na+,K+-ATPase show significant inhibition of this ion pump when cisplatin is present in the cytoplasm. Because Na+,K+-ATPase activity is essential to the survival of all animal cells, e.g. via maintenance of cell volume, and the Na+,K+-ATPase is expressed at particularly high levels within the membranes of kidney tubules where it plays a crucial role in nutrient reabsorption, these results suggest that cisplatin-induced inhibition of the Na+,K+-ATPase is a likely contributing cause for the nephrotoxicity of cisplatin.DFG, EXC 314, Unifying Concepts in Catalysi
Dietary Protein and Bone Health Across the Life-Course : an updated systematic review and meta-analysis over 40 years
Abstract Purpose: This systematic review and meta-analysis analysed the relationship between dietary protein and bone health across the life-course. Methods: The PubMed database was searched for all relevant human studies from the 1st 4 January 1976 to 22nd January 2016, including all bone outcomes except calcium metabolism. Results: The searches identified 127 papers for inclusion, including 74 correlational studies, 23 fracture or osteoporosis risk studies and 30 supplementation trials. Protein intake accounted for 0 - 4% of areal BMC and areal BMD variance in adults and 0-14% of areal BMC variance in children and adolescents. However, when confounder adjusted (5 studies) adult lumbar spine and femoral neck BMD associations were not statistically significant. There was no association between protein intake and relative risk (RR) of osteoporotic fractures for total (RR(random) = 0.94; 0.72 to 1.23, I2=32%), animal (RR (random) = 0.98; 0.76 to 1.27, I2 = 46%) or vegetable protein (RR (fixed)= 0.97 (0.89 to 1.09, I2 = 15%). In total protein supplementation studies, pooled effect sizes were not statistically significant for LSBMD (total n=255, MD(fixed)=0.04 g/cm2 (0.00 to 0.08, P=0.07), I2=0%) or FNBMD (total n=435, MD(random)=0.01 g/cm2 (-0.03 to 0.05, P=0.59), I2=68%). Conclusions: There appears to be little benefit of increasing protein intake for bone health in healthy adults but there is also clearly no indication of any detrimental effect, at least within the protein intakes of the populations studied (around 0.8-1.3 g/Kg/day). More studies are urgently required on the association between protein intake and bone health in children and adolescents. Key Words: Aging, Epidemiology, IGF-1, Nutrition, Osteoporosis, Die
Synthesis and characterisation of pyrene-labelled polydimethylsiloxane networks: towards the in situ detection of strain in silicone elastomers
Pyrene-substituted polyhydromethylsiloxanes (PHMS-Py-x) were synthesised by the hydrosilylation reaction of prop-3-enyloxymethylpyrene with polyhydromethylsiloxane (M-n = 3700). The ratio of pyrene substituent to Si-H unit was varied to afford a range of pyrene-functionalised polysiloxanes. These copolymers were subsequently incorporated into polydimethylsiloxane (PDMS) elastomers by curing via either Pt(0) catalysed hydrosilylation with divinyl-terminated PDMS (M-n = 186) and tetrakis(dimethylsiloxy) silane, or Sn(II) catalysed condensation with alpha,omega-dihydroxyPDMS (M-n = 26 000) and tetraethoxysilane. An alternative method involving the synthesis and integration of [3-(pyren-1-ylmethoxy)propyl]triethoxysilane (Py-TEOS) into PDMS elastomers was also investigated: a mixture of alpha,omega-dihydroxyPDMS (M-n = 26 000), tetraethoxysilane, and Py-TEOS was cured using an Sn( II) catalyst. Certain of the resulting fluorescent pyrene-labelled elastomers were studied by differential scanning calorimetry and dynamic mechanical analysis. No significant changes were observed in the thermal or mechanical properties of the elastomers containing pyrene when compared to otherwise identical samples not containing pyrene. All of the pyrene-containing elastomers were demonstrated to be fluorescent under suitable excitation in a photoluminescent spectrometer. Two of the elastomers were placed in a photoluminescence spectrometer and subjected to cycles of extension and relaxation (strain = 0-16.7%) while changes in the emission spectra were monitored. The resulting spectra of the elastomer containing the PHMS-Py-50 copolymers were variable and inconsistent. However, the emission peaks of elastomers containing Py-TEOS displayed clear and reproducible changes in fluorescence intensity upon stretching and relaxation. The intensity of the monomer and excimer emission peaks was observed to increase with elongation of the sample and decrease upon relaxation. Furthermore, the ratio of the intensities of the excimer : monomer peak decreased with elongation and increased with relaxation. In neither case was there appreciable hysteresis, suggesting that fluorescent labelling of elastomers is a valid approach for the non-invasive in situ monitoring of stress and strain in such materials
The association between green space and cause-specific mortality in urban New Zealand: an ecological analysis of green space utility
<b>Background:</b>
There is mounting international evidence that exposure to green environments is associated with health benefits, including lower mortality rates. Consequently, it has been suggested that the uneven distribution of such environments may contribute to health inequalities. Possible causative mechanisms behind the green space and health relationship include the provision of physical activity opportunities, facilitation of social contact and the restorative effects of nature. In the New Zealand context we investigated whether there was a socioeconomic gradient in green space exposure and whether green space exposure was associated with cause-specific mortality (cardiovascular disease and lung cancer). We subsequently asked what is the mechanism(s) by which green space availability may influence mortality outcomes, by contrasting health associations for different types of green space.
<b>Methods:</b>
This was an observational study on a population of 1,546,405 living in 1009 small urban areas in New Zealand. A neighbourhood-level classification was developed to distinguish between usable (i.e., visitable) and non-usable green space (i.e., visible but not visitable) in the urban areas. Negative binomial regression models were fitted to examine the association between quartiles of area-level green space availability and risk of mortality from cardiovascular disease (n = 9,484; 1996 - 2005) and from lung cancer (n = 2,603; 1996 - 2005), after control for age, sex, socio-economic deprivation, smoking, air pollution and population density.
<b>Results:</b>
Deprived neighbourhoods were relatively disadvantaged in total green space availability (11% less total green space for a one standard deviation increase in NZDep2001 deprivation score, p < 0.001), but had marginally more usable green space (2% more for a one standard deviation increase in deprivation score, p = 0.002). No significant associations between usable or total green space and mortality were observed after adjustment for confounders.
<b>Conclusion</b>
Contrary to expectations we found no evidence that green space influenced cardiovascular disease mortality in New Zealand, suggesting that green space and health relationships may vary according to national, societal or environmental context. Hence we were unable to infer the mechanism in the relationship. Our inability to adjust for individual-level factors with a significant influence on cardiovascular disease and lung cancer mortality risk (e.g., diet and alcohol consumption) will have limited the ability of the analyses to detect green space effects, if present. Additionally, green space variation may have lesser relevance for health in New Zealand because green space is generally more abundant and there is less social and spatial variation in its availability than found in other contexts
- âŠ