Fat oxidation at rest and during exercise in male monozygotic twins

Purpose We aimed to investigate if hereditary factors, leisure-time physical activity (LTPA) and metabolic health interact with resting fat oxidation (RFO) and peak fat oxidation (PFO) during ergometer cycling. Methods We recruited 23 male monozygotic twin pairs (aged 32-37 years) and determined their RFO and PFO with indirect calorimetry for 21 and 19 twin pairs and for 43 and 41 twin individuals, respectively. Using physical activity interviews and the Baecke questionnaire, we identified 10 twin pairs as LTPA discordant for the past 3 years. Of the twin pairs, 8 pairs participated in both RFO and PFO measurements, and 2 pairs participated in either of the measurements. We quantified the participants' metabolic health with a 2-h oral glucose tolerance test. Results Fat oxidation within co-twins was correlated at rest [intraclass correlation coefficient (ICC) = 0.54, 95% confidence interval (CI) 0.15-0.78] and during exercise (ICC = 0.67, 95% CI 0.33-0.86). The LTPA-discordant pairs had no pairwise differences in RFO or PFO. In the twin individual-based analysis, PFO was positively correlated with the past 12-month LTPA (r = 0.26, p = 0.034) and the Baecke score (r = 0.40, p = 0.022) and negatively correlated with the area under the curve of insulin (r = - 0.42, p = 0.015) and glucose (r = - 0.31, p = 0.050) during the oral glucose tolerance test. Conclusions Hereditary factors were more important than LTPA for determining fat oxidation at rest and during exercise. Additionally, PFO, but not RFO, was associated with better metabolic health.Peer reviewe

Synthesis of Carbon Nanotubes and Nanofibers on Silica and Cement Matrix Materials

In order to create strong composite materials, a good dispersion of carbon nanotubes (CNTs) and nanofibers (CNFs) in a matrix material must be obtained. We proposed a simple method of growing the desirable carbon nanomaterial directly on the surface of matrix particles. CNTs and CNFs were synthesised on the surface of model object, silica fume particles impregnated by iron salt, and directly on pristine cement particles, naturally containing iron oxide. Acetylene was successfully utilised as a carbon source in the temperature range from 550 to 750 C. 5–10 walled CNTs with diameters of 10–15 nm at 600 C and 12–20 nm at 750 C were synthesised on silica particles. In case of cement particles, mainly CNFs with a diameter of around 30 nm were grown. It was shown that high temperatures caused chemical and physical transformation of cement particles.Peer reviewe

A novel cement-based hybrid material

Carbon nanotubes (CNTs) and carbon nanofibers (CNFs) are known to possess exceptional tensile strength, elastic modulus and electrical and thermal conductivity. They are promising candidates for the next-generation high-performance structural and multi-functional composite materials. However, one of the largest obstacles to creating strong, electrically or thermally conductive CNT/CNF composites is the difficulty of getting a good dispersion of the carbon nanomaterials in a matrix. Typically, time-consuming steps of purification and functionalization of the carbon nanomaterial are required. We propose a new approach to grow CNTs/CNFs directly on the surface of matrix particles. As the matrix we selected cement, the most important construction material. We synthesized in a simple one-step process a novel cement hybrid material (CHM), wherein CNTs and CNFs are attached to the cement particles. The CHM has been proven to increase 2 times the compressive strength and 40 times the electrical conductivity of the hardened paste, i.e. concrete without sand.Peer reviewe

Role of Menopausal Transition and Physical Activity in Loss of Lean and Muscle Mass: A Follow-Up Study in Middle-Aged Finnish Women

In midlife, women experience hormonal changes due to menopausal transition. A decrease especially in estradiol has been hypothesized to cause loss of muscle mass. This study investigated the effect of menopausal transition on changes in lean and muscle mass, from the total body to the muscle fiber level, among 47–55-year-old women. Data were used from the Estrogenic Regulation of Muscle Apoptosis (ERMA) study, where 234 women were followed from perimenopause to early postmenopause. Hormone levels (estradiol and follicle stimulating hormone), total and regional body composition (dual-energy X-ray absorptiometry (DXA) and computed tomography (CT) scans), physical activity level (self-reported and accelerometer-measured) and muscle fiber properties (muscle biopsy) were assessed at baseline and at early postmenopause. Significant decreases were seen in lean body mass (LBM), lean body mass index (LBMI), appendicular lean mass (ALM), appendicular lean mass index (ALMI), leg lean mass and thigh muscle cross-sectional area (CSA). Menopausal status was a significant predictor for all tested muscle mass variables, while physical activity was an additional significant contributor for LBM, ALM, ALMI, leg lean mass and relative muscle CSA. Menopausal transition was associated with loss of muscle mass at multiple anatomical levels, while physical activity was beneficial for the maintenance of skeletal muscle mass

Added Value of Vaisala AQT530 Sensors as a Part of a Sensor Network for Comprehensive Air Quality Monitoring

Poor air quality influences the quality of life in the urban environment. The regulatory observation stations provide the backbone for the city administration to monitor urban air quality. Recently a suite of cost-effective air quality sensors has emerged to provide novel insights into the spatio-temporal variability of aerosol particles and trace gases. Particularly in low concentrations these sensors might suffer from issues related e.g., to high detection limits, concentration drifts and interdependency between the observed trace gases and environmental parameters. In this study we characterize the optical particle detector used in AQT530 (Vaisala Ltd.) air quality sensor in the laboratory. We perform a measurement campaign with a network of AQT530 sensors in Helsinki, Finland in 2020-2021 and present a long-term performance evaluation of five sensors for particulate (PM10, PM2.5) and gaseous (NO2, NO, CO, O-3) components during a half-year co-location study with reference instruments at an urban traffic site. Furthermore, short-term (3-5 weeks) co-location tests were performed for 25 sensors to provide sensor-specific correction equations for the fine-tuning of selected pollutants in the sensor network. We showcase the added value of the verified network of 25 sensor units to address the spatial variability of trace gases and aerosol mass concentrations in an urban environment. The analysis assesses road and harbor traffic monitoring, local construction dust monitoring, aerosol concentrations from fireworks, impact of sub-urban small scale wood combustion and detection of long-range transport episodes on a city scale. Our analysis illustrates that the calibrated network of Vaisala AQT530 air quality sensors provide new insights into the spatio-temporal variability of air pollution within the city. This information is beneficial to, for example, optimization of road dust and construction dust emission control as well as provides data to tackle air quality problems arising from traffic exhaust and localized wood combustion emissions in the residential areas.Peer reviewe

Total and regional body adiposity increases during menopause—evidence from a follow‐up study

For women, menopausal transition is a time of significant hormonal changes, which may contribute to altered body composition and regional adipose tissue accumula-tion. Excess adiposity, and especially adipose tissue accumulation in the central body region, increases women's risk of cardiovascular and metabolic conditions and affects physical functioning. We investigated the associations between menopausal progres-sion and total and regional body adiposity measured with dual- energy X- ray absorpti-ometry and computed tomography in two longitudinal cohort studies of women aged 47– 55 (n= 230 and 148, mean follow- up times 1.3 ± 0.7 and 3.9 ± 0.2 years, mean baseline BMI 25.5 kg/m2). We also examined associations between menopausal pro -gression and skeletal muscle fiber characteristics, as well as adipose tissue- derived adipokines. Relative increases of 2%– 14% were observed in regional and total body adiposity measures, with a pronounced fat mass increase in the android area (4% and 14% during short- and long- term follow- ups). Muscle fiber oxidative and glycolytic capacities and intracellular adiposity were not affected by menopause, but were dif-ferentially correlated with total and regional body adiposity at different menopausal stages. Menopausal progression and regional adipose tissue masses were positively associated with serum adiponectin and leptin, and negatively associated with resistin levels. Higher diet quality and physical activity level were also inversely associated with several body adiposity measures. Therefore, healthy lifestyle habits before and during menopause might delay the onset of severe metabolic conditions in women

Menopause modulates the circulating metabolome : evidence from a prospective cohort study

Aims We studied the changes in the circulating metabolome and their relation to the menopausal hormonal shift in 17β-oestradiol and follicle-stimulating hormone levels among women transitioning from perimenopause to early postmenopause. Methods and results We analysed longitudinal data from 218 Finnish women, 35 of whom started menopausal hormone therapy during the study. The menopausal transition was monitored with menstrual diaries and serum hormone measurements. The median follow-up was 14 months (interquartile range: 8–20). Serum metabolites were quantified with targeted nuclear magnetic resonance metabolomics. The model results were adjusted for age, follow-up duration, education, lifestyle, and multiple comparisons. Menopause was associated with 85 metabolite measures. The concentration of apoB (0.17 standard deviation [SD], 99.5% confidence interval [CI] 0.03–0.31), very-low-density lipoprotein triglycerides (0.25 SD, CI 0.05–0.45) and particles (0.21 SD, CI 0.05–0.36), low-density lipoprotein (LDL) cholesterol (0.17 SD, CI 0.01–0.34) and particles (0.17 SD, CI 0.03–0.31), high-density lipoprotein (HDL) triglycerides (0.24 SD, CI 0.02–0.46), glycerol (0.32 SD, CI 0.07–0.58) and leucine increased (0.25 SD, CI 0.02–0.49). Citrate (−0.36 SD, CI −0.57 to −0.14) and 3-hydroxybutyrate concentrations decreased (−0.46 SD, CI −0.75 to −0.17). Most metabolite changes were associated with the menopausal hormonal shift. This explained 11% and 9% of the LDL cholesterol and particle concentration increase, respectively. Menopausal hormone therapy was associated with increased medium-to-large HDL particle count and decreased small-to-medium LDL particle and glycine concentration. Conclusions Menopause is associated with proatherogenic circulating metabolome alterations. Female sex hormones levels are connected to the alterations, highlighting their impact on women’s cardiovascular health.peerReviewe

Weight loss induces changes in adaptive thermogenesis in female and male physique athletes

Physique athletes lose substantial weight preparing for competitions, potentially altering systemic metabolism. We investigated sex differences in body composition, resting energy expenditure (REE), and appetite-regulating and thyroid hormone changes during a competition preparation among drug-free physique athletes. The participants were female (10 competing (COMP) and 10 non-dieting controls (CTRL)) and male (13 COMP) and 10 CTRL)) physique athletes. COMP were tested before they started their diet 23 weeks before competing (PRE), during their diet one week before competing (MID), and 23 weeks after competing (POST) whereas CTRL were tested at similar intervals but did not diet. Measurements included body composition by DXA, muscle size, and subcutaneous fat thickness (SFA) by ultrasound, REE by indirect calorimetry, circulating ghrelin, leptin T3, and T4 hormone analysis. Fat mass (FM) and SFA decreased in both sexes (p<0.001), while males (p<0.001) lost more lean mass (LM) than females (p<0.05). Weight loss, decreased energy intake, and increased aerobic exercise (p<0.05) led to decreased LM and FM-adjusted REE (p<0.05), reflecting metabolic adaptation. Absolute leptin levels decreased in both sexes (p<0.001) but more among females (p<0.001) due to higher baseline leptin levels. These changes occurred with similar decreases in T3 (p<0.001) and resting heart rate (p<0.01) in both sexes. CTRL, who were former or upcoming physique athletes, showed no systematic changes in any measured variables. In conclusion, while dieting, female and male physique athletes experience REE and hormonal changes leading to adaptive thermogenesis. However, responses seemed temporary as they returned toward baseline after the recovery phase. ClinicalTrials.gov (NCT04392752).peerReviewe

Extracellular vesicles and high‐density lipoproteins : Exercise and oestrogen‐responsive small RNA carriers

Decreased systemic oestrogen levels (i.e., menopause) affect metabolic health. However, the detailed mechanisms underlying this process remain unclear. Both oestrogens and exercise have been shown to improve metabolic health, which may be partly mediated by circulating microRNA (c-miR) signalling. In recent years, extracellular vesicles (EV) have increased interest in the field of tissue crosstalk. However, in many studies on EV-carried miRs, the co-isolation of high-density lipoprotein (HDL) particles with EVs has not been considered, potentially affecting the results. Here, we demonstrate that EV and HDL particles have distinct small RNA (sRNA) content, including both host and nonhost sRNAs. Exercise caused an acute increase in relative miR abundancy in EVs, whereas in HDL particles, it caused an increase in transfer RNA-derived sRNA. Furthermore, we demonstrate that oestrogen-based hormonal therapy (HT) allows the acute exercise-induced miR-response to occur in both EV and HDL particles in postmenopausal women, while the response was absent in nonusers.peerReviewe

Circulating metabolome landscape in Lynch syndrome

Circulating metabolites systemically reflect cellular processes and can modulate the tissue microenvironment in complex ways, potentially impacting cancer initiation processes. Genetic background increases cancer risk in individuals with Lynch syndrome; however, not all carriers develop cancer. Various lifestyle factors can influence Lynch syndrome cancer risk, and lifestyle choices actively shape systemic metabolism, with circulating metabolites potentially serving as the mechanical link between lifestyle and cancer risk. This study aims to characterize the circulating metabolome of Lynch syndrome carriers, shedding light on the energy metabolism status in this cancer predisposition syndrome.This study consists of a three-group cross-sectional analysis to compare the circulating metabolome of cancer-free Lynch syndrome carriers, sporadic colorectal cancer (CRC) patients, and healthy non-carrier controls. We detected elevated levels of circulating cholesterol, lipids, and lipoproteins in LS carriers. Furthermore, we unveiled that Lynch syndrome carriers and CRC patients displayed similar alterations compared to healthy non-carriers in circulating amino acid and ketone body profiles. Overall, cancer-free Lynch syndrome carriers showed a unique circulating metabolome landscape.This study provides valuable insights into the systemic metabolic landscape of Lynch syndrome individuals. The findings hint at shared metabolic patterns between cancer-free Lynch syndrome carriers and CRC patients.Peer reviewe