Search

Factors such as host species, phylogeny, diet, and both timing and location of sampling are thought to influence the composition of gut-associated bacteria in insects. In this study, we compared the faecal-associated bacterial taxa for three Coenagrion and one Enallagma damselfly species. We expected high overlap in representation of bacterial taxa due to the shared ecology and diet of these species. Using metabarcoding based on the 16S rRNA gene, we identified 1513 sequence variants, representing distinct bacterial ‘taxa’. Intriguingly, the damselfly species showed somewhat different magnitudes of richness of ZOTUs, ranging from 480 to 914 ZOTUs. In total, 921 (or 60.8% of the 1513) distinct ZOTUs were non-shared, each found only in one species, and then most often in only a single individual. There was a surfeit of these non-shared incidental ZOTUs in the Enallagma species accounting for it showing the highest bacterial richness and accounting for a sample-wide pattern of more single-species ZOTUs than expected, based on comparisons to the null model. Future studies should address the extent to which faecal bacteria represent non-incidental gut bacteria and whether abundant and shared taxa are true gut symbionts. Pictures of odonates adopted from Norske Art databank under Creative Commons License (CC BY 4.0). [ABSTRACT FROM AUTHOR]

Aims/hypothesis. Fat accumulation in the liver has been shown to be closely correlated with hepatic insulin resistance and features of insulin resistance, also independently of body weight. It remains to be established how fat in the liver correlates with that in other depots, and whether any association differs between men and women. Methods. Liver fat (assessed using proton spectroscopy), intra-abdominal and subcutaneous fat (measured using magnetic resonance imaging) and markers of insulin resistance, including serum adiponectin, were determined in 132 non-diabetic subjects: 66 men (age 41±1 years) and 66 women (age 42±1 years). Results. Although the women had almost twice as much subcutaneous fat as the men (5045±207 vs 2610±144 cm3, p<0.0001), amounts of intra-abdominal fat (1305±80 vs 1552±111 cm3, NS) and liver fat (6.7±0.8 vs 8.9±1.2%, NS) were similar. In this study, no sex differences were observed with respect to serum insulin, adiponectin, triglyceride and HDL cholesterol concentrations. Of all measures of body composition, liver fat was best correlated with serum insulin (r=0.58, p<0.001), with no difference observed between men and women. Serum adiponectin was inversely correlated with liver fat content (r=-0.21, p<0.05). Multiple linear regression analysis revealed that intra-abdominal fat was significantly associated with liver fat, independently of serum adiponectin and subcutaneous fat. Liver fat, but not intra-abdominal fat, significantly explained the variation in serum insulin concentrations. Conclusions/interpretation. Intra-abdominal fat is independently associated with liver fat, whereas subcutaneous fat is not. Liver fat, but not intra-abdominal fat, is independently associated with serum insulin. Men and women with similar amounts of intra-abdominal and liver fat do not exhibit sex differences in markers of insulin resistance (serum insulin, triglycerides, HDL cholesterol and adiponectin). [ABSTRACT FROM AUTHOR]

OBJECTIVE:: Platelet aggregation responses to acetylsalicylic acid (ASA) show considerable interindividual variation, the causes of which are largely unknown. We determined whether variation in insulin action is associated with that of ASA on platelets. SUBJECTS:: In all, 10 nonobese (age 50±3?y, BMI 25±1?kg/m2) and 11 obese (age 52±2?y, BMI 32±1?kg/m2) subjects. MEASUREMENTS:: Insulin sensitivity of glucose uptake was determined by the euglycemic insulin clamp technique. Platelet aggregation responses to four doses of arachidonic acid (AA) and adenosine diphosphate (ADP) were assessed in platelet-rich plasma before and 1?h after ingestion of 50?mg ASA using Born's turbidometric aggregometer. RESULTS:: Whole-body insulin sensitivity (M-value 0-180?min) was 36% lower in the obese (4.5±0.6) than the nonobese (7.1±0.6?mg/kg?min, P<0.01) group. Before ASA, all doses of AA induced complete aggregation. After ASA ingestion, ASA inhibited maximal aggregation more in the nonobese than the obese group at AA concentrations of 0.75, 1 and 1.5?mmol/l (P=0.016 for ANOVA). ADP-induced aggregation at high doses (2 and 3?umol/l) was also less inhibited in the obese group. In vivo insulin sensitivity (r=-0.68, P<0.001 for 1?mmol/l AA) and BMI (r=0.58, P<0.01 for 1?mmol/l AA) were closely correlated with residual aggregation after ASA administration. CONCLUSION:: These data demonstrate that obese insulin-resistant subjects have a blunted response to platelet-inhibitory effect of ASA. If this blunted effect is of a single dose of ASA preserved in continuous use, it could contribute to the increased risk of atherothrombosis in insulin-resistant individuals.International Journal of Obesity (2003) 27, 907-911. doi:10.1038/sj.ijo.0802312 [ABSTRACT FROM AUTHOR]

We present an optimal algorithm to determine whether a placement of N isothetic non-overlapping rectangles (macros) can be represented by a slicing tree, and if so, to find a representation of minimal height. A slicing is a recursive partition of the overall bounding rectangle, by straight horizontal or vertical cuts, into rectangular regions, each one containing exactly one macro. The algorithm first determines a representation of the empty space of the placement by means of maximally extended horizontal and vertical channels. A second phase then generates a maximal slicing tree (an ordered tree with unbounded degree and maximal branching, i.e., minimal height) in a top-down fashion. The complexity of each phase is O( N log N). The problem arises in steps (1) and (2) of our top-down approach to VLSI custom chip design, which consists of (1) floorplanning by slicing, (2) hierarchicial global wiring, and (3) detailed layout of macros. [ABSTRACT FROM AUTHOR]