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Background and Aims: The leaf economic spectrum (LES) is related to dry mass and nutrient investments towards photosynthetic processes and leaf structures, and to the duration of returns on those investments (leaf lifespan, LL). Phosphorus (P) is a key limiting nutrient for plant growth, yet it is unclear how the allocation of leaf P among different functions is coordinated with the LES. We addressed this question among 12 evergreen woody species co-occurring on P-impoverished soils in south-eastern Australia. Methods: Leaf 'economic' traits, including LL, leaf mass per area (LMA), light-saturated net photosynthetic rate per mass (Amass), dark respiration rate, P concentration ([Ptotal]), nitrogen concentration, and P resorption, were measured for three pioneer and nine non-pioneer species. Leaf P was separated into five functional fractions: orthophosphate P (Pi), metabolite P (PM), nucleic acid P (PN), lipid P (PL), and residual P (PR; phosphorylated proteins and unidentified compounds that contain P). Results: LL was negatively correlated with Amass and positively correlated with LMA, representing the LES. Pioneers occurred towards the short-LL end of the spectrum and exhibited higher [Ptotal] than non-pioneer species, primarily associated with higher concentrations of Pi, PN and PL. There were no significant correlations between leaf P fractions and LL or LMA, while Amass was positively correlated with the concentration of PR. Conclusions: Allocation of leaf P to different fractions varied substantially among species. This variation was partially associated with the LES, which may provide a mechanism underlying co-occurrence of species with different ecological strategies under P limitation. [ABSTRACT FROM AUTHOR]

Obesity and chronic disease are increasing problems in refugee populations. Afghani refugees undergoing hepatitis B vaccination between January 2015 and December 2017 at a general practice clinic received dietary counselling sessions in Dari by native speaking clinicians. Anthropometry, blood pressure, fasting lipids and liver function tests were measured at both visits with results compared over time. 110/119 refugees requiring hepatitis B vaccination were recruited into the study. Mean BMI was lower at follow up visits (25.4 vs 26.1 by wilcoxon signed rank test p 0.04) with 72 of 110 participants losing a median of 2 kg between visits (range 0.5–14 kg) a mean of 206 days after the initial consultation. Median triglyceride levels were lower at the second visit than the first (1.4 vs 1.3 mmol/L Wilcoxon signed rank test Z = 3.5, p 0.0004). This cohort of refugees lost weight and showed a small improvement in triglyceride levels between visits. [ABSTRACT FROM AUTHOR]

To understand how environmental conditions and reproductive events affect coral energetic status, seasonal variations in lipid and fatty acid profiles of the common scleractinian coral, Acropora millepora, were studied from pre-spawning in November 2009 until post-spawning in November 2010 at Halfway Island (in the Keppel Island Group, Southern Great Barrier Reef, Australia). Seasonal chlorophyll levels, photosynthetically active radiation (PAR), rainfall and water temperature were major drivers of the overall coral lipid profile, and this was particularly pronounced in correlations with the important, high-energy lipid, triacylglycerol. This likely reflected changing food sources and feeding modes (i.e. phototrophy vs heterotrophy), which corresponds to the opportunistic feeding behaviour of corals. Water temperature was also a major influencer of the coral fatty acid profile. In particular, saturated fatty acids correlated positively with water temperature, while polyunsaturated fatty acids correlated negatively, reflecting cell membrane fluidity regulation, which is necessary for coral to tolerate changing temperatures. Spawning and maternal provisioning also proved to be a major driver of change in the coral lipid profile. The mass spawning events in spring for both 2009 and 2010 caused reductions in the important coral egg constituents: wax ester, triacylglycerol, phosphatidylcholine and fatty acid 10:0. Interestingly, lipid accumulation was significantly lower in the 2010 spawn compared to 2009, possibly due to lower PAR and chlorophyll levels, reflecting reduced photosynthetic activity and phytoplankton availability. Regardless, in 2010, resource provisioning to egg production was greater than in 2009, suggesting increased reproductive effort in the face of environmental stress. This study demonstrates the strong influence of opportunistic heterotrophy and autotrophy and maternal provisioning on the coral lipid profile. Such information is fundamental to understanding the environmental and biochemical processes underlying coral health and predicting how anomalous events and climate-driven changes will affect coral reef assemblages. [ABSTRACT FROM AUTHOR]

Dyslipidaemia is a known risk factor for developing cardiovascular disease. The impact of ethnicity on variations in lipid patterns has been studied in certain racial and ethnic groups with limited data on other ethnicities, particularly Asian subgroups. This cross-sectional study evaluated the ethnic variation in lipid profile and its association with body composition and diet in ninety-one overweight and obese Australians of European (n = 32), Indian (n = 28) and Iranian (n = 31) ancestries. Different measures of total and truncal adiposity were assessed using the method of whole body dual energy X-ray absorptiometry. The results showed that serum total cholesterol (TC) and low density lipoprotein cholesterol (LDL-chol) levels in Iranians were significantly lower than in Europeans and Indians. Both Iranian and Indian groups exhibited lower mean high density lipoprotein cholesterol (HDL-chol) relative to Europeans. Triglycerides (TG) and HDL-chol, but not TC and LDL-chol, were significantly associated with different truncal adiposity measurements; however the degree of associations varied in ethnic groups. Regression analysis showed ethnicity as a significant predictor of TC ( p = 0.01), TG ( p = 0.03) and HDL-chol ( p = 0.04), after controlling for potential confounders. However, LDL-chol was significantly associated with the intake of total ( p = 0.005), and saturated fats ( p = 0.004), which were also other significant determinants of serum TC ( p = 0.04 and p = 0.02, respectively). In conclusion, ethnicity was a strong predictor of serum lipids, except LDL-chol which was significantly determined by dietary fat intake. Prevention and management of obesity, particularly abdominal adiposity may effectively reduce the risk of low HDL-chol reported in Iranians and Indians. [ABSTRACT FROM AUTHOR]

In fluctuating aquatic environments such as intermittent streams, fish condition is often highly variable due to the associated fluctuating levels of food resources. Having the physiological capacity to both metabolise and catabolise lipids, fish can survive through droughts and rapidly gain condition during flows and floods. Dryland rivers continuously cycle through periods of boom and bust due to their intermittent patterns of rainfall and flow. To help gain an understanding of how fish respond physiologically to varying antecedent flow conditions, we examined body condition measured by percent tissue water content of two generalist fish species in an Australian dryland river. We predicted that fish would be in better condition following recent flows and poorer condition when there had been no recent flows. Our expectations were met for both species with low water tissue content after high flows and high tissue water content after significant drying. It was also found that strong juvenile recruitment was also evident when body condition was high, indicating that when there are food resource spikes driven by flow pulses fish can utilise resources both to produce offspring and to store as lipid for future survival. [ABSTRACT FROM AUTHOR]

The composition of lipids and fatty acids was determined for the livers, muscle, pancreas, kidney and stomach fluids of deepwater chondrichthyan species (including 11 squaliformes, 3 chimaeriformes, 1 hexanchiforme and 3 carcharhiniformes) caught as bycatch from continental waters off south-eastern Australia. The lipid class, fatty acid and fatty alcohol composition differed markedly in each tissue and in each species. The lipid and fatty acid composition of large, lipid-rich (38–70% wet weight, ww) livers demonstrated the multifunctional role of this organ in: lipid distribution, storage and biosynthesis, and buoyancy regulation. In the liver, the importance of certain lipids (including squalene, diacylglyceryl ethers, triacylglycerols and to a lesser extent wax esters) as mediators of buoyancy varied according to lifestyle and habitat. Less variability was observed in the muscle profiles, characterized by low lipid content (<1.0% ww) and high relative levels of polar lipids (>70%). The lipid and fatty acid profiles of the kidney and pancreas showed the highest intraspecific variability, suggesting these organs also have complex roles in lipid storage and metabolism. Overall intra- and interspecific differences in the tissue fatty acid profiles could be related to differences in a number of factors including phylogeny, habitat (depth), buoyancy regulation and diet and presumably also reflect different ecological roles. The lipid and fatty acid profiles are the first published for Rhinochimaera pacifica, Chimaera lignaria and Figaro boardmani and the first to demonstrate interspecific variation in lipid profiles of various tissues of deepwater chondrichthyans. The application of multivariate analysis to lipid class and fatty acid tissue profiles in chondrichthyans inferred dietary differences and metabolic preferences between species and habitats. These results have important implications for the future use of fatty acids as dietary tracers in chondrichthyan research. [ABSTRACT FROM AUTHOR]

Background: Cardiovascular disease (CVD) remains a leading cause of death across the world and poses a significant economic burden. Research regarding per-person use and cost of cardiovascular pharmaceuticals in Australia, as well as potential predictors of pharmaceutical costs in populations using the 'bottom up' costing approach, is limited. Previous studies have adopted 'top down' costing approaches and have been based largely on hypothetical examples and considered only inpatient settings. Objective: To determine the distribution of pharmaceutical costs (from a governmental perspective) related to each cardiovascular risk factor for individuals with, or at high risk of, CVD by analysing data for Australian participants enrolled in the Reduction of Atherothrombosis for Continued Health (REACH) Registry. Methods: 2873 participants were recruited for the REACH Registry through 273 general (primary care) practices in Australia. Included among data collected at baseline was a cardiovascular medicines review. Average weighted costs per person were estimated using Government-reimbursed prices (2007). Annual costs were stratified by sex, age, disease group and other co-morbidities. A multivariate linear regression model was utilized to reveal the predictors of the pharmaceutical costs. Results: The average annual median cost of cardiovascular pharmaceuticals per person was Australian dollars ($A)1310. Use of lipid-lowering agents, non-aspirin (acetylsalicylic acid) antiplatelet agents and thiazolidinediones (glitazones) added significantly to the average annual per-person costs. The multivariate regression model showed that the predictors of annual pharmaceutical costs were dyslipidemia (b coefficient value [marginal annual cost associated with a condition] $A691; p < 0.001), hypertension ($A346; p < 0.001), vascular disease ($A340; p < 0.001), diabetes mellitus ($A298; p < 0.001), and obesity ($A52; p = 0.03). The same predictors, together with sex, were shown to have an impact on the number of medicines used. Conclusions: Among community-based Australians with, or at risk of, CVD, independent drivers of annual cardiovascular pharmaceutical costs are dyslipidemia (which accounts for half of perperson costs), followed by hypertension, established CVD, and diabetes. Obesity also independently adds to the cost of cardiovascular pharmaceuticals in community-based Australians with, or at risk of, CVD. [ABSTRACT FROM AUTHOR]

Background:Features of the metabolic syndrome comprise a major risk for cardiovascular disease and will increase in prevalence with rising childhood obesity. We sought to identify early life influences on development of obesity, hypertension and dyslipidemia in children.Methods and results:Cluster analysis was used on a subset of a longitudinal Australian birth cohort who had blood samples at age 8 (n=406). A quarter of these 8-year-olds fell into a cluster with higher body mass index, blood pressure (BP), more adverse lipid profile and a trend to higher serum glucose resembling adult metabolic syndrome. There was a U-shaped relationship between percentage of expected birth weight (PEBW) and likelihood of being in the high-risk cluster. The high-risk cluster had elevated BP and weight as early as 1 and 3 years old. Increased likelihood of the high-risk cluster group occurred with greatest weight gain from 1 to 8 years old (odds ratio (OR)=1.4, 95% confidence interval (CI)=1.3–1.5/kg) and if mothers smoked during pregnancy (OR=1.82, CI=1.05–3.2). Risk was lower if children were breast fed for 4 months (OR=0.6, 95% CI=0.37–0.97). Newborns in the upper two quintiles for PEBW born to mothers who smoked throughout pregnancy were at greatest risk (OR=14.0, 95% CI=3.8–51.1) compared to the nadir PEBW quintile of non-smokers.Conclusion:A U-shaped relationship between birth weight and several components of the metabolic syndrome was confirmed in a contemporary, well-nourished Western population of full-term newborns, but post-natal weight gain was the dominant factor associated with the high-risk cluster. There was a prominence of higher as well as lowest birth weights in those at risk. Future health programs should focus on both pre- and post-natal factors (reducing excess childhood weight gain and smoking during pregnancy), and possibly the greatest benefits may arise from targeting the heaviest, as well as lightest newborns, especially with a history of maternal smoking during pregnancy.International Journal of Obesity (2007) 31, 236–244. doi:10.1038/sj.ijo.0803394; published online 23 May 2006 [ABSTRACT FROM AUTHOR]

Heavy kava use has been associated with sudden death in Aboriginal Australians in Arnhem Land (Northern Territory, Australia) where poor diets and a high incidence of premature coronary heart disease are known. Heavy kava users may suffer additional risk if further malnourished. Among 98 people (62 males, 36 females) in one community, 36 never used kava, 26 were past users, and 36 were continuing users. Across kava-using groups skinfold thickness, body mass index and body fat decreased. Total- and LDL-cholesterol were elevated in kava users compared to both former users and never users. HDL-cholesterol was higher in current users vs never users. Across kava-using groups, triglycerides, homocysteine and diet-derived antioxidant vitamins a-tocopherol and retinol, did not vary. Plasma carotenoid levels (indicative of vegetable and fruit intake) were very low, but when adjusted for plasma cholesterol, did not vary between kava-using groups. An obsession for kava drinking may mediate kava's direct effects on nutritional status.European Journal of Clinical Nutrition (2004) 58, 1090-1093. doi:10.1038/sj.ejcn.1601921 [ABSTRACT FROM AUTHOR]