1,258 research outputs found
Reducing Premature Death and Renal Failure in Australian Aborigines: A Community-Based Cardiovascular and Renal Program
Objective: To describe results of a systematic treatment program to modify renal and cardiovascular disease in an Aboriginal community whose rates of renal failure and cardiovascular deaths are among the highest in Australia. Design: Longitudinal survey of people during treatment, and comparison of rates of natural death and renal failure with those in a historical control group. Setting: Tiwi Islands (population, about 1800), November 1995 to December 1998. Participants: All adults with blood pressure 140/90, with diabetes and urinary albumin/creatinine ratio (ACR) 3.4 g/mol (microalbuminuria threshold), or with progressive overt albuminuria (ACR 34 g/mol) were eligible for treatment. The historical control group comprised 229 people who satisfied these criteria in the pretreatment period 1992-1995. Interventions: Perindopril, combined with calcium-channel blockers and diuretics if needed to achieve blood pressure goals; attempts to improve control of blood glucose and lipid levels; health education. Main outcome measures: Blood pressure, ACR, serum creatinine level and glomerular filtration rate (GFR) over two years of treatment; rates of renal failure and natural death compared with control group (analysed on intention-to-treat basis). Results: 258 people enrolled in the program, and 118 had complete data for two years of treatment. In these 118, blood pressures fell significantly, while ACR and GFR stabilised. Rates of the combined endpoints of renal failure and natural death per 100 person-years were 2.9 for the treatment group (95% CI, 1.7-4.6) and 4.8 for the control group (95% CI, 3.3-7.0). After adjustment for baseline ACR category, the relative risk of the treatment group versus the control group for these combined endpoints was 0.47 (95% CI, 0.25-0.86; P = 0.013). Treatment benefit was especially marked in people with overt albuminuria or hypertension and in non-diabetic people. The estimates of benefit were supported by a fall in community rates of death and renal failure. Conclusions: Aboriginal people can participate enthusiastically in chronic disease management, with rapid, dramatic improvement in clinical profiles and mortality. Similar programs should be introduced urgently into other Aboriginal communities nationwide
Human epicardial adipose tissue expresses a pathogenic profile of adipocytokines in patients with cardiovascular disease
Introduction: Inflammation contributes to cardiovascular disease and is exacerbated with
increased adiposity, particularly omental adiposity; however, the role of epicardial fat is poorly
understood.
Methods: For these studies the expression of inflammatory markers was assessed in epicardial fat
biopsies from coronary artery bypass grafting (CABG) patients using quantitative RT-PCR. Further,
the effects of chronic medications, including statins, as well as peri-operative glucose, insulin and
potassium infusion, on gene expression were also assessed. Circulating resistin, CRP, adiponectin
and leptin levels were determined to assess inflammation.
Results: The expression of adiponectin, resistin and other adipocytokine mRNAs were
comparable to that in omental fat. Epicardial CD45 expression was significantly higher than control
depots (p < 0.01) indicating significant infiltration of macrophages. Statin treated patients showed
significantly lower epicardial expression of IL-6 mRNA, in comparison with the control abdominal
depots (p < 0.001). The serum profile of CABG patients showed significantly higher levels of both
CRP (control: 1.28 ± 1.57 μg/mL vs CABG: 9.11 ± 15.7 μg/mL; p < 0.001) and resistin (control:
10.53 ± 0.81 ng/mL vs CABG: 16.8 ± 1.69 ng/mL; p < 0.01) and significantly lower levels of
adiponectin (control: 29.1 ± 14.8 μg/mL vs CABG: 11.9 ± 6.0 μg/mL; p < 0.05) when compared to
BMI matched controls.
Conclusion: Epicardial and omental fat exhibit a broadly comparable pathogenic mRNA profile,
this may arise in part from macrophage infiltration into the epicardial fat. This study highlights that
chronic inflammation occurs locally as well as systemically potentially contributing further to the
pathogenesis of coronary artery disease
Managing Protein in Spring Wheat with Aerial and Satellite Imagery
Nitrogen fertilizer application can help wheat growers increase crop value and marketability by increasing grain quality. Nitrogen (N) is often applied at heading as a method of increasing protein content and therefore quality of wheat. Our objectives were to obtain spectral signatures of wheat under various N rates (0, 72, 180, 234 kg N ha-1), test various spectral methods of identifying crop stress, and observe the grain protein response to a midseason N application. Spectral data from satellite and aerial platforms were compared to preseason N treatments and flag-leaf tissue samples. Spectral data correlated well with preseason and flag leaf tissue analysis (r2 = 0.58-0.82). Grain protein increased on plots that received an additional 54 kg of N ha-1 at anthesis almost 2% in the N stressed plots (72 kg N ha-1) and 0.3-0.4% on plots with sufficient N (234 and 180 kg N ha-1). Wheat stress detected and managed with help from satellite and aerial platforms could help growers increase revenue and decrease N over-application
The Epidemiological Framework for Biological Invasions (EFBI): An interdisciplinary foundation for the assessment of biosecurity threats
Emerging microparasite (e.g. viruses, bacteria, protozoa and fungi) epidemics and the introduction of non-native pests and weeds are major biosecurity threats worldwide. The likelihood of these threats is often estimated from probabilities of their entry, establishment, spread and ease of prevention. If ecosystems are considered equivalent to hosts, then compartment disease models should provide a useful framework for understanding the processes that underpin non-native species invasions. To enable greater cross-fertilisation between these two disciplines, the Epidemiological Framework for Biological Invasions (EFBI) is developed that classifies ecosystems in relation to their invasion status: Susceptible, Exposed, Infectious and Resistant. These states are linked by transitions relating to transmission, latency and recovery. This viewpoint differs markedly from the species-centric approaches often applied to non-native species. It allows generalisations from epidemiology, such as the force of infection, the basic reproductive ratio R0, super-spreaders, herd immunity, cordon sanitaire and ring vaccination, to be discussed in the novel context of non-native species and helps identify important gaps in the study of biological invasions. The EFBI approach highlights several limitations inherent in current approaches to the study of biological invasions including: (i) the variance in non-native abundance across ecosystems is rarely reported; (ii) field data rarely (if ever) distinguish source from sink ecosystems; (iii) estimates of the susceptibility of ecosystems to invasion seldom account for differences in exposure to non-native species; and (iv) assessments of ecosystem susceptibility often confuse the processes that underpin patterns of spread within -and between- ecosystems. Using the invasion of lakes as a model, the EFBI approach is shown to present a new biosecurity perspective that takes account of ecosystem status and complements demographic models to deliver clearer insights into the dynamics of biological invasions at the landscape scale. It will help to identify whether management of the susceptibility of ecosystems, of the number of vectors, or of the diversity of pathways (for movement between ecosystems) is the best way of limiting or reversing the population growth of a non-native species. The framework can be adapted to incorporate increasing levels of complexity and realism and to provide insights into how to monitor, map and manage biological invasions more effectively
Renewed investigations at Taung; 90 years after Australopithecus africanus
2015 marked the 90th anniversary of the description of the first fossil ofAustralopithecus africanus, commonly known as the Taung Child, which was unearthed during blasting at the Buxton-Norlim Limeworks (referred to as the BNL) 15 km SE of the town of Taung, South Africa. Subsequently, this site has been recognized as a UNESCO World Heritage site on the basis of its importance to southern African palaeoanthropology. Some other sites such as Equus Cave and Black Earth Cave have also been investigated; but the latter not since the 1940s. These sites indicate that the complex of palaeontological and archaeological localities at the BNL preserve a time sequence spanning the Pliocene to the Holocene. The relationship of these various sites and how they fit into the sequence of formation of tufa,
landscapes and caves at the limeworks have also not been investigated or discussed in detail since Peabody’s efforts in the 1940s. In this contribution we mark the 90th anniversary of the discovery and description of the Taung Child by providing a critical review of previous work at Taung based on our recent preliminary work at the site. This includes a reassessment of the Taung Child Type Site, as well as renewed excavations at Equus Cave and the lesser-known locality and little-investigated Black Earth Cave. Preliminary results suggest that much of our previous understandings of the BNL’s formational history and site formation processes need to be reassessed. Only through detailed analysis on the BNL as a whole can we understand this complex depositional environment
Comparing breast cancer mortality rates before-and-after a change in availability of screening in different regions: Extension of the paired availability design
BACKGROUND: In recent years there has been increased interest in evaluating breast cancer screening using data from before-and-after studies in multiple geographic regions. One approach, not previously mentioned, is the paired availability design. The paired availability design was developed to evaluate the effect of medical interventions by comparing changes in outcomes before and after a change in the availability of an intervention in various locations. A simple potential outcomes model yields estimates of efficacy, the effect of receiving the intervention, as opposed to effectiveness, the effect of changing the availability of the intervention. By combining estimates of efficacy rather than effectiveness, the paired availability design avoids confounding due to different fractions of subjects receiving the interventions at different locations. The original formulation involved short-term outcomes; the challenge here is accommodating long-term outcomes. METHODS: The outcome is incident breast cancer deaths in a time period, which are breast cancer deaths that were diagnosed in the same time period. We considered the plausibility of the basic five assumptions of the paired availability design and propose a novel analysis to accommodate likely violations of the assumption of stable screening effects. RESULTS: We applied the paired availability design to data on breast cancer screening from six counties in Sweden. The estimated yearly change in incident breast cancer deaths per 100,000 persons ages 40–69 (in most counties) due to receipt of screening (among the relevant type of subject in the potential outcomes model) was -9 with 95% confidence interval (-14, -4) or (-14, -5), depending on the sensitivity analysis. CONCLUSION: In a realistic application, the extended paired availability design yielded reasonably precise confidence intervals for the effect of receiving screening on the rate of incident breast cancer death. Although the assumption of stable preferences may be questionable, its impact will be small if there is little screening in the first time period. However, estimates may be substantially confounded by improvements in systemic therapy over time. Therefore the results should be interpreted with care
Preparation and characterisation of manganese, cobalt and zinc DNA nanoflowers with tuneable morphology, DNA content and size
Recently reported DNA nanoflowers are an interesting class of organic-inorganic hybrid materials which are prepared using DNA polymerases. DNA nanoflowers combine the high surface area and scaffolding of inorganic Mg2P2O7 nanocrystals with the targeting properties of DNA, whilst adding enzymatic stability and enhanced cellular uptake. We have investigated conditions for chemically modifying the inorganic core of these nanoflowers through substitution of Mg2+ with Mn2+, Co2+ or Zn2+ and have characterised the resulting particles. These have a range of novel nanoarchitectures, retain the enzymatic stability of their magnesium counterparts and the Co2+ and Mn2+ DNA nanoflowers have added magnetic properties. We investigate conditions to control different morphologies, DNA content, hybridisation properties, and size. Additionally, we show that DNA nanoflower production is not limited to Ф29 DNA polymerase and that the choice of polymerase can influence the DNA length within the constructs. We anticipate that the added control of structure, size and chemistry will enhance future application
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