The effects of collagen peptides on muscle damage, inflammation and bone turnover following exercise:a randomized, controlled trial

This study examined whether consuming collagen peptides (CP) before and after strenuous exercise alters markers of muscle damage, inflammation and bone turnover. Using a double-blind, independent group’s design, 24 recreationally active males consumed either 20 g day−1 of CP or a placebo control (CON) for 7 days before and 2 days after performing 150 drop jumps. Maximal isometric voluntary contractions, countermovement jumps (CMJ), muscle soreness (200 mm visual analogue scale), pressure pain threshold, Brief Assessment of Mood Adapted (BAM +) and a range of blood markers associated with muscle damage, inflammation and bone turnover C-terminal telopeptide of type 1 collagen (β-CTX) and N-terminal propeptides of type 1 pro-collagen (P1NP) were measured before supplementation (baseline; BL), pre, post, 1.5, 24 and 48 h post-exercise. Muscle soreness was not significantly different in CP and CON (P = 0.071) but a large effect size was evident at 48 h postexercise, indicative of lower soreness in the CP group (90.42 ± 45.33 mm vs. CON 125.67 ± 36.50 mm; ES = 2.64). CMJ height recovered quicker with CP than CON at 48 h (P = 0.050; CP 89.96 ± 12.85 vs. CON 78.67 ± 14.41% of baseline values; ES = 0.55). There were no statistically significant effects for the other dependent variables (P > 0.05). β-CTX and P1NP were unaffected by CP supplementation (P > 0.05). In conclusion, CP had moderate benefits for the recovery of CMJ and muscle soreness but had no influence on inflammation and bone collagen synthesis

Biomarkers in Maternal and Newborn Blood Indicate Heightened Fetal Susceptibility to Procarcinogenic DNA Damage

Polycyclic aromatic hydrocarbons (PAHs) such as benzo[a]pyrene (BaP) are widespread air contaminants released by transportation vehicles, power generation, and other combustion sources. Experimental evidence indicates that the developing fetus is more susceptible than the adult to carcinogenic effects of PAHs, although laboratory studies in rodents suggest that the dose to fetal tissues is an order of magnitude lower than that to maternal tissues. To assess fetal versus adult susceptibility to PAHs and environmental tobacco smoke (ETS), we compared carcinogen-DNA adducts (a biomarker associated with increased cancer risk) and cotinine (a biomarker of tobacco smoke exposure) in paired blood samples collected from mothers and newborns in New York City. We enrolled 265 nonsmoker African-American and Latina mother–newborn pairs in New York City between 1997 and 2001 (estimated average ambient air BaP concentrations < 0.5 ng/m(3)). Despite the estimated 10-fold lower fetal dose, mean levels of BaP-DNA adducts as determined by high-performance liquid chromatography–fluorescence were comparable in paired New York City newborn and maternal samples (0.24 adducts per 10(8) nucleotides, 45% of newborns with detectable adducts vs. 0.22 per 10(8) nucleotides, 41% of mothers with detectable adducts). However, by the Wilcoxon signed-rank test, the levels in newborns were higher (p = 0.02). Mean cotinine was higher in newborns than in mothers (1.7 ng/mL, 47% detectable vs. 1.28 ng/mL, 44% detectable). Consistent with our prior study in a Caucasian Polish population, these results indicate increased susceptibility of the fetus to DNA damage and reduced ability to clear ETS constituents. The findings have implications for risk assessment, given the need to protect children as a sensitive subset of the population

Influence of effective stress on swelling pressure of expansive soils

The volume change and shear strength behaviour of soils are controlled by the effective stress. Recent advances in unsaturated soil mechanics have shown that the effective stress as applicable to unsaturated soils is equal to the difference between the externally applied stress and the suction stress. The latter can be established based on the soil-water characteristic curve (SWCC) of the soil. In the present study, the evolution of swelling pressure in compacted bentonite-sand mixtures was investigated. Comparisons were made between magnitudes of applied suction, suction stress, and swelling pressure

The effects of collagen peptides on exercise-induced gastro-intestinal stress: a randomized, controlled trial

Purpose: We examined the effects of collagen peptides (CP) supplementation on exercise induced-gastro-intestinal (GI) stress. Methods: In a randomized, crossover design, 20 volunteers (16 males: V ̇O2max, 53.4±5.9 ml·kg-1) completed 3 trials: a non-exercise rest trial, with no supplement (REST) and then an exercise trial with CP (10 g·day-1) or placebo control (CON) supplements, which were consumed for 7 days prior to, and 45 min before, a 70 min run at 70-90% of V ̇O2max. Outcome measures included urinary lactulose and rhamnose (L/R), intestinal fatty acid binding protein (I-FABP), lipopolysaccharide (LPS), anti-LPS antibody, monocyte chemoattractant protein-1 (MCP-1), interleukin (IL) 6 and 8, cortisol, alkaline phosphatase (ALP) (measured pre, 10 min post and 2 h post) and subjective GI symptoms. Results: There were no differences in heart rate, perceived exertion, thermal comfort, or core temperature during exercise in the CP and CON trials (all P>0.05). I-FABP was higher in CP (2538±1221pg/ml) and CON (2541±766pg/ml) vs. REST 2 h post (1893±1941pg/ml) (both P0.05), and no differences in L/R or GI symptoms between CON and CP (all P>0.05). Conclusion: Collagen peptides did not modify exercise-induced changes in inflammation, GI integrity or subjective GI symptoms but LPS was higher in CON 2 h post-exercise and thus future studies may be warranted

Mass and Hot Baryons in Massive Galaxy Clusters from Subaru Weak Lensing and AMiBA SZE Observations

We present a multiwavelength analysis of a sample of four hot (T_X>8keV) X-ray galaxy clusters (A1689, A2261, A2142, and A2390) using joint AMiBA Sunyaev-Zel'dovich effect (SZE) and Subaru weak lensing observations, combined with published X-ray temperatures, to examine the distribution of mass and the intracluster medium (ICM) in massive cluster environments. Our observations show that A2261 is very similar to A1689 in terms of lensing properties. Many tangential arcs are visible around A2261, with an effective Einstein radius \sim 40 arcsec (at z \sim 1.5), which when combined with our weak lensing measurements implies a mass profile well fitted by an NFW model with a high concentration c_{vir} \sim 10, similar to A1689 and to other massive clusters. The cluster A2142 shows complex mass substructure, and displays a shallower profile (c_{vir} \sim 5), consistent with detailed X-ray observations which imply recent interaction. The AMiBA map of A2142 exhibits an SZE feature associated with mass substructure lying ahead of the sharp north-west edge of the X-ray core suggesting a pressure increase in the ICM. For A2390 we obtain highly elliptical mass and ICM distributions at all radii, consistent with other X-ray and strong lensing work. Our cluster gas fraction measurements, free from the hydrostatic equilibrium assumption, are overall in good agreement with published X-ray and SZE observations, with the sample-averaged gas fraction of = 0.133 \pm 0.027, for our sample = (1.2 \pm 0.1) \times 10^{15} M_{sun} h^{-1}. When compared to the cosmic baryon fraction f_b = \Omega_b/\Omega_m constrained by the WMAP 5-year data, this indicates /f_b = 0.78 \pm 0.16, i.e., (22 \pm 16)% of the baryons are missing from the hot phase of clusters.Comment: accepted for publication in ApJ; high resolution figures available at http://www.asiaa.sinica.edu.tw/~keiichi/upfiles/AMiBA7/ms_highreso.pd

Collagen peptide supplementation before bedtime reduces sleep fragmentation and improves cognitive function in physically active males with sleep complaints

Purpose: The primary aim of this study was to examine whether a glycine-rich collagen peptides (CP) supplement could enhance sleep quality in physically active men with self-reported sleep complaints. Methods: In a randomized, crossover design, 13 athletic males (age: 24 ± 4 years; training volume; 7 ± 3 h·wk1) with sleep complaints (Athens Insomnia Scale, 9 ± 2) consumed CP (15 g·day1) or a placebo control (CON) 1 h before bedtime for 7 nights. Sleep quality was measured with subjective sleep diaries and actigraphy for 7 nights; polysomnographic sleep and core temperature were recorded on night 7. Cognition, inflammation, and endocrine function were measured on night 7 and the following morning. Subjective sleepiness and fatigue were measured on all 7 nights. The intervention trials were separated by ≥7 days and preceded by a 7-night familiarisation trial. Results: Polysomnography showed less awakenings with CP than CON (21.3±9.7 vs. 29.3±13.8 counts, respectively; P=0.028). The 7-day average for subjective awakenings were less with CP vs. CON (1.3±1.5 vs. 1.9±0.6 counts, respectively; P=0.023). The proportion of correct responses on the baseline Stroop cognitive test were higher with CP than CON (1.0±0.00 vs. 0.97±0.05 AU, respectively; P=0.009) the morning after night 7. There were no trial differences in core temperature, endocrine function, inflammation, subjective sleepiness, fatigue and sleep quality, or other measures of cognitive function or sleep (P>0.05). Conclusion: CP supplementation did not influence sleep quantity, latency, or efficiency, but reduced awakenings and improved cognitive function in physically active males with sleep complaints

Accurate Whole-Genome Sequencing and Haplotyping from 10 to 20 Human Cells

Recent advances in whole genome sequencing have brought the vision of personal genomics and genomic medicine closer to reality. However, current methods lack clinical accuracy and the ability to describe the context (haplotypes) in which genome variants co-occur in a cost-effective manner. Here we describe a low-cost DNA sequencing and haplotyping process, Long Fragment Read (LFR) technology, similar to sequencing long single DNA molecules without cloning or separation of metaphase chromosomes. In this study, ten LFR libraries were made using only ~100 pg of human DNA per sample. Up to 97% of the heterozygous single nucleotide variants (SNVs) were assembled into long haplotype contigs. Removal of false positive SNVs not phased by multiple LFR haplotypes resulted in a final genome error rate of 1 in 10 Mb. Cost-effective and accurate genome sequencing and haplotyping from 10-20 human cells, as demonstrated here, will enable comprehensive genetic studies and diverse clinical applications

The assessment of circulating volume using inferior vena cava collapse index and carotid Doppler velocity time integral in healthy volunteers: a pilot study

International audienceBackground: Assessment of circulating volume and the requirement for fluid replacement are fundamental to resuscitation but remain largely empirical. Passive leg raise (PLR) may determine fluid responders while avoiding potential fluid overload. We hypothesised that inferior vena cava collapse index (IVCCI) and carotid artery blood flow would change predictably in response to PLR, potentially providing a non-invasive tool to assess circulating volume and identifying fluid responsive patients.Methods: We conducted a prospective proof of concept pilot study on fasted healthy volunteers. One operator measured IVC diameter during quiet respiration and sniff, and carotid artery flow. Stroke volume (SV) was also measured using suprasternal Doppler. Our primary endpoint was change in IVCCI after PLR. We also studied changes in IVCCI after “sniff”, and correlation between carotid artery flow and SV.Results: Passive leg raise was associated with significant reduction in the mean inferior vena cava collapsibility index from 0.24 to 0.17 (p < 0.01). Mean stroke volume increased from 56.0 to 69.2 mL (p < 0.01). There was no significant change in common carotid artery blood flow. Changes in physiology consequent upon passive leg raise normalised rapidly.Discussion: Passive leg raise is associated with a decrease of IVCCI and increase in stroke volume. However, the wide range of values observed suggests that factors other than circulating volume predominate in determining the proportion of collapse with respiration.Conclusion: In contrast to other studies, we did not find that carotid blood flow increased with passive leg raise. Rapid normalisation of post-PLR physiology may account for this

BRCA2 polymorphic stop codon K3326X and the risk of breast, prostate, and ovarian cancers

Background: The K3326X variant in BRCA2 (BRCA2*c.9976A&gt;T; p.Lys3326*; rs11571833) has been found to be associated with small increased risks of breast cancer. However, it is not clear to what extent linkage disequilibrium with fully pathogenic mutations might account for this association. There is scant information about the effect of K3326X in other hormone-related cancers. Methods: Using weighted logistic regression, we analyzed data from the large iCOGS study including 76 637 cancer case patients and 83 796 control patients to estimate odds ratios (ORw) and 95% confidence intervals (CIs) for K3326X variant carriers in relation to breast, ovarian, and prostate cancer risks, with weights defined as probability of not having a pathogenic BRCA2 variant. Using Cox proportional hazards modeling, we also examined the associations of K3326X with breast and ovarian cancer risks among 7183 BRCA1 variant carriers. All statistical tests were two-sided. Results: The K3326X variant was associated with breast (ORw = 1.28, 95% CI = 1.17 to 1.40, P = 5.9x10- 6) and invasive ovarian cancer (ORw = 1.26, 95% CI = 1.10 to 1.43, P = 3.8x10-3). These associations were stronger for serous ovarian cancer and for estrogen receptor–negative breast cancer (ORw = 1.46, 95% CI = 1.2 to 1.70, P = 3.4x10-5 and ORw = 1.50, 95% CI = 1.28 to 1.76, P = 4.1x10-5, respectively). For BRCA1 mutation carriers, there was a statistically significant inverse association of the K3326X variant with risk of ovarian cancer (HR = 0.43, 95% CI = 0.22 to 0.84, P = .013) but no association with breast cancer. No association with prostate cancer was observed. Conclusions: Our study provides evidence that the K3326X variant is associated with risk of developing breast and ovarian cancers independent of other pathogenic variants in BRCA2. Further studies are needed to determine the biological mechanism of action responsible for these associations