Row for Your Life: A Century of Mortality Follow-Up of French Olympic Rowers

Background/Aim

Strenuous endurance training required to participate in the highest sports level has been associated with deleterious effects on elite athletes'' health and cardiac abnormalities. We aimed to describe overall mortality and main causes of deaths of male French rowers participating in at least one Olympic Game (OG) from 1912 to 2012 in comparison with the French general population.

Methods

Identity information and vital status of French Olympic rowers were validated by National sources from 1912 to 2013 (study''s endpoint) among 203 rowers; 52 out of 255 (20.3%) were excluded because their vital statuses could not be confirmed. Main causes of deaths were obtained from the National registry from 1968 up to 2012. Overall and disease-specific mortalities were calculated through standardised mortality ratios (SMRs) with its 95% confidence intervals (CIs). The overall mortality was calculated for the whole rowers'' cohort (PT) and for two periods apart: (P1) including rowers from 1912 to 1936 OG, a cohort in which all rowers have deceased and (P2) considering rowers from 1948 to 2012 OG.

Results

Among the 203 rowers analysed, 46 died before the study''s endpoint, mainly from neoplasms (33%), cardiovascular diseases (21%) and external causes (18%). PT demonstrates a significant 42% lower overall mortality (SMR: 0.58, 95% CI: 0.43–0.78, p<0.001), P1 a 37% reduction (SMR: 0.63, 95% CI: 0.43–0.89, p = 0.009) and P2 a 60% reduction (SMR: 0.40, 95% CI: 0.23–0.65, p<0.001) compared with their compatriots. Mortality due to cardiovascular diseases is significantly reduced (SMR: 0.41, 95% CI: 0.16–0.84, p = 0.01) among rowers.

Conclusions

French Olympic rowers benefit of lower overall mortality compared with the French general population. Among rowers'' main causes of death, cardiovascular diseases are reduced in relation to their compatriots. Analytical studies with larger samples are needed to understand the reasons for such reductions.     

Lispro insulin and metformin versus other combination in the diabetes mellitus type 2 management after secondary oral antidiabetic drug failure

The purpose of the study was to find out differences between treatments of diabetes type 2 after secondary oral antidiabetic drug failure. Three different methods of treatment were compared: lispro insulin in combination with metformin, glimepiride and metformin combination or two daily doses of biphasic insulin 30/70 together with bed-time NPH insulin. The study included 87 patients with diabetes mellitus type 2 randomly distributed into 3 different treatment groups. Fasting and postprandial glucose were analyzed by enzymatic colorimetric method and HbA1c was measured by ion exchange chromatography. HbA1c significantly decreased in all three study groups. The decrease was mostly expressed among patients treated with lispro and metformin. When focused on postprandial glucose control, antihyperglycemic metformin and insulin lispro therapy has greater impact on the overall metabolic control (decrease in level of HbA1c) in comparison with the above mentioned more traditional approaches.     

Detection of extracellular vesicles in the mouse vaginal fluid: Their delivery of sperm proteins that stimulate capacitation and modulate fertility

Extracellular vesicles (EVs) were isolated by ultracentrifugation of vaginal luminal fluid (VLF) from superovulated mice and identified for the first time using transmission electron microscopy. Characterized by size and biochemical markers (CD9 and HSC70), EVs were shown to be both microvesicular and exosomal and were dubbed as “Vaginosomes” (VGS). Vaginal cross-sections were analyzed to visualize EVs in situ: EVs were present in the lumen and also embedded between squamous epithelial and keratinized cells, consistent with their endogenous origin. Western blots detected Plasma membrane Ca²⁺-ATPase 1 (PMCA1) and tyrosine-phosphorylated proteins in the VGS cargo and also in uterosomes. Flow cytometry revealed that following coincubation of caudal sperm and VLF for 30 min, the frequencies of cells with the highest Sperm adhesion molecule 1 (SPAM1), PMCA1/4, and PMCA1 levels increased 16.4-, 8.2-, and 27-fold, respectively; compared with control coincubated in phosphate buffered saline (PBS). Under identical conditions, sperm tyrosine-phosphorylated proteins were elevated ~3.3-fold, after VLF coincubation. Progesterone-induced acrosome reaction (AR) rates were significantly (p < 0.001) elevated in sperm coincubated with VGS for 10–30 min, compared with PBS. Sperm artificially deposited in the vaginas of superovulated females for these periods also showed significant (p < 0.01) increases in AR rates, compared with PBS. Thus in vitro and in vivo, sperm acquire from the vaginal environment factors that induce capacitation, explaining recent findings for their acrosomal status in the isthmus. Overall, VGS appear to deliver higher levels of proteins involved in preventing premature capacitation and AR than those promoting them. Our findings which have implications for humans open the possibility of new approaches to infertility treatment with exosome therapeutics.     

Testing of novel net cleaning technologies for finfish aquaculture

To avoid the negative impacts caused by biofouling development, aquaculture nets around the world are periodically cleaned using high-pressure washers. Net cleaning is labour-intense and costly, can damage antifouling coatings on the nets, and pose contamination as well as fish health and welfare risks. To support the environmental sustainability of the growing aquaculture sector, novel net cleaning methods are needed. This study examined low-pressure-, cavitation-, and suction-based cleaning technologies as alternatives to conventional high-pressure cleaning. Using field experiments, cleaning efficacy, cleaning waste generation, and the impact of cleaning on coating integrity and net strength were evaluated. Cavitation and high-pressure cleaning achieved considerably higher cleaning efficacy than low-pressure and suction cleaning. However, a single high-pressure treatment caused up to 53% coating degradation, compared to 2% for cavitation. All technologies produced similar cleaning waste and neither reduced net strength significantly. This study identifies cavitation cleaning as promising technology for biofouling control on aquaculture nets.     

A new paradigm for regulation of protein phosphatase 2A function via Src and Fyn kinase–mediated tyrosine phosphorylation

Protein phosphatase 2A (PP2A) is a major phospho-Ser/Thr phosphatase and a key regulator of cellular signal transduction pathways. While PP2A dysfunction has been linked to human cancer and neurodegenerative disorders such as Alzheimer’s disease (AD), PP2A regulation remains relatively poorly understood. It has been reported that the PP2A catalytic subunit (PP2Ac) is inactivated by a single phosphorylation at the Tyr307 residue by tyrosine kinases such as v-Src. However, multiple mass spectrometry studies have revealed the existence of other putative PP2Ac phosphorylation sites in response to activation of Src and Fyn, two major Src family kinases (SFKs). Here, using PP2Ac phosphomutants and novel phosphosite-specific PP2Ac antibodies, we show that cellular pools of PP2Ac are instead phosphorylated on both Tyr127 and Tyr284 upon Src activation, and on Tyr284 following Fyn activation. We found these phosphorylation events enhanced the interaction of PP2Ac with SFKs. In addition, we reveal SFK-mediated phosphorylation of PP2Ac at Y284 promotes dissociation of the regulatory Bα subunit, altering PP2A substrate specificity; the phosphodeficient Y127/284F and Y284F PP2Ac mutants prevented SFK-mediated phosphorylation of Tau at the CP13 (pSer202) epitope, a pathological hallmark of AD, and SFK-dependent activation of ERK, a major growth regulatory kinase upregulated in many cancers. Our findings demonstrate a novel PP2A regulatory mechanism that challenges the existing dogma on the inhibition of PP2A catalytic activity by Tyr307 phosphorylation. We propose dysregulation of SFK signaling in cancer and AD can lead to alterations in PP2A phosphorylation and subsequent deregulation of key PP2A substrates, including ERK and Tau.     

Life-History and Spatial Determinants of Somatic Growth Dynamics in Komodo Dragon Populations

Somatic growth patterns represent a major component of organismal fitness and may vary among sexes and populations due to genetic and environmental processes leading to profound differences in life-history and demography. This study considered the ontogenic, sex-specific and spatial dynamics of somatic growth patterns in ten populations of the world’s largest lizard the Komodo dragon (Varanus komodoensis). The growth of 400 individual Komodo dragons was measured in a capture-mark-recapture study at ten sites on four islands in eastern Indonesia, from 2002 to 2010. Generalized Additive Mixed Models (GAMMs) and information-theoretic methods were used to examine how growth rates varied with size, age and sex, and across and within islands in relation to site-specific prey availability, lizard population density and inbreeding coefficients. Growth trajectories differed significantly with size and between sexes, indicating different energy allocation tactics and overall costs associated with reproduction. This leads to disparities in maximum body sizes and longevity. Spatial variation in growth was strongly supported by a curvilinear density-dependent growth model with highest growth rates occurring at intermediate population densities. Sex-specific trade-offs in growth underpin key differences in Komodo dragon life-history including evidence for high costs of reproduction in females. Further, inverse density-dependent growth may have profound effects on individual and population level processes that influence the demography of this species.     

The HUPO initiative on Model Organism Proteomes, iMOP

The community working on model organisms is growing steadily and the number of model organisms for which proteome data are being generated is continuously increasing. To standardize efforts and to make optimal use of proteomics data acquired from model organisms, a new Human Proteome Organisation (HUPO) initiative on model organism proteomes (iMOP) was approved at the HUPO Ninth Annual World Congress in Sydney, 2010. iMOP will seek to stimulate scientific exchange and disseminate HUPO best practices. The needs of model organism researchers for central databases will be better represented, catalyzing the integration of proteomics and organism-specific databases. Full details of iMOP activities, members, tools and resources can be found at our website http://www.imop.uzh.ch/ and new members are invited to join us.