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Poor physical function is associated with adverse health outcomes in old adults. Several variables, e.g., nutrition, physical activity (PA), body composition, hematological variables, medication and cognitive function have been associated with physical function. However, findings from studies have been inconsistent and it is not known which are independent predictors of physical function. We conducted a cross-sectional study including 236 community dwelling old people (age range: 65–92 years, 58.2% female) in Reykjavik, Iceland. Timed-up-and-go (TUG), 6-minutes-wallk-for distance (6MWD), nutrition, PA, body composition, blood chemical variables, medication and cognitive function were assessed. We found bivariate correlations between physical function with body composition, strength, physical activity, number of medications, hematological variables, cognitive function, energy and protein intake. According to hierarchical linear models, body composition, strength, number of medications, PA and cognitive function were predictors of physical function but not hematological variables. Results were similar for both 6MWD and TUG and the strongest modifiable predictors in the final models were quadriceps strength/bodyweight (N/kg) ((+16.1m, P=0.001; -0.4sec,P=0.001), physical activity (h/week) (+2.2m, P=0.001; -0.04sec,P=0.021) and number of medications (-8.1m, P=0.003; +0.2sec,P=0.021). In community dwelling old adults, physical function decreases with age. However, there are modifiable determinants of physical function, in particular strength for a given body weight, PA and number of medications, which might give the possibility to maintain or improve physical function in this age group.

Metabolic dysregulation affects physical performance among older adults. Metabolic syndrome (MetS) is an index of collected risk factors for cardiovascular disease/diabetes and the prevalence of MetS increases with aging. However, there is little information for the longitudinal association between MetS and physical function. We investigated the effects of a 12-week resistance exercise programme on physical function among community dwelling old adults with and without MetS. Total 236 subjects (73.7 ± 5.7 years, 58.2% female) participated in the exercise intervention and 210 people completed the program. MetS was defined according to the NIH criteria (having ≥three risk factors, i.e., increased waist circumference, triglycerides, HDL cholesterol, blood pressure, fasting glucose). Objectively measured physical function included 6-minutes-walk-for-distance (6MWD), grip strength, timed-up-and-og (TUG) and knee extension strength. The prevalence of MetS was 33% (n=78). The improvement of 6MWD from baseline to endpoint was 39.0 ± 33.2 meter for people without MetS, and 22.1 ± 35.5 meter for people with MetS. The linear regression model was performed to examine the association between baseline MetS and improvement of each physical performance after the intervention. Compared with those without MetS, those with MetS improved significantly less in 6MWD (β=-14.6, 95% Confidence interval; -26.5 to -2.7, P

Resistance exercise is important for the prevention of sarcopenia and physical dependence of old adults. However, little is known whether overweight/obesity affect the outcomes of a resistance exercise program. Community dwelling Icelandic old adults (N=236, 73.7 ± 5.7 years) participated in a 12-week resistance exercise program. Anthropometrics, muscular strength and physical function were measured at baseline and endpoint. Participants were grouped retrospectively into normal-, overweight and obese according to BMI. Statistical analyses were corrected for age and gender. Of the participants, 22.0% were normal-, 41.4% were overweight and 36.6% were obese. All groups experienced improvements in outcome measurements, but improvements in obese individuals were less pronounced compared to normal weight individuals. Normal weight individuals gained more lean mass (+0.70kg,P=0.015), appendicular muscle mass (+0.42kg,P=0.007) but tended to loose more fat mass (-0.75kg,P=0.081) as compared to obese. Absolute gains in quadriceps strength were similar between groups, but relative to body weight, normal weight subject gained more than obese subjects (+0.31N/kg,P=0.017). This translated into an greater improvement in 6-minutes-walk-for-distance (+24. m,P< 0.001) compared to obese subjects. Interestingly, grip strength increased more in obese subjects (2.4 lb.,P=0.020). Timed-up-and-go improved similarly in all groups (-0,64sec,P< 0.001). Independently from their body weight status, old adults benefited from a resistance exercise program in terms of body composition and physical function. However, obese individuals improved significantly less than normal weight participants although there was similar attendance to the exercise classes. Great care has to be taken of obese elderly in order to maintain their physical independence as long as possible.

Systematic mapping of the bedrock beneath the Icelandic ice caps began in 1980. We continue this effort by presenting a detailed bedrock digital elevation model (DEM) of Drangajökull ice cap in NW-Iceland, surveyed using radio echo sounding (RES) in March 2014. About 590 km of RES profiles, generally with 200–300 m spacing, were surveyed. This is to date the densest set of RES profiles measured on an Icelandic ice cap. We describe the processing of the radar profiles and construction of the bedrock DEM. We also analyse possible errors of surveyed glacier thickness along the profiles and discuss the accuracy of the final bedrock DEM. The bedrock DEM reveals topography with the same general character as other areas of NW-Iceland (Vestfirðir). The new bedrock DEM and a series of surface DEMs allow estimates of total ice cap volume and relative volume change since the mid-20th century. The bedrock data combined with the most accurate available surface DEM of Drangajökull, from July 2011, reveals a total ice cap volume of 15.4±0.4 km³, of which ∼71\% was stored on the west side of the ice cap. At that time the average thickness of Drangajökull was 107±3 m and the maximum observed thickness, found on Kaldalónsjökull outlet glacier, was 284±14 m. In 1946–2014, the total ice cap volume (in autumn) was reduced from ∼18 km³ to ∼15 km³. Approximately half of this volume was lost in 1994–2011. We describe and discuss several interesting phenomena revealed by the RES data and the derived bedrock DEM. The presented bedrock data also helps to explain curious surface features in the accumulation area of NE-Drangajökull.

International audience; Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are prevalent liver conditions that underlie the development of life-threatening cirrhosis, liver failure and liver cancer. Chronic necro-inflammation is a critical factor in development of NASH, yet the cellular and molecular mechanisms of immune dysregulation in this disease are poorly understood. Here, using single-cell transcriptomic analysis, we comprehensively profiled the immune composition of the mouse liver during NASH. We identified a significant pathology-associated increase in hepatic conventional dendritic cells (cDCs) and further defined their source as NASH-induced boost in cycling of cDC progenitors in the bone marrow. Analysis of blood and liver from patients on the NAFLD/NASH spectrum showed that type 1 cDCs (cDC1) were more abundant and activated in disease. Sequencing of physically interacting cDC-T cell pairs from liver-draining lymph nodes revealed that cDCs in NASH promote inflammatory T cell reprogramming, previously associated with NASH worsening. Finally, depletion of cDC1 in XCR1DTA mice or using anti-XCL1-blocking antibody attenuated liver pathology in NASH mouse models. Overall, our study provides a comprehensive characterization of cDC biology in NASH and identifies XCR1+ cDC1 as an important driver of liver pathology.