Effects of sex and joint action on voluntary activation

The current study tested the hypothesis that voluntary activation during maximal voluntary contraction (MVC) conditionally depends on sex and joint action. Twenty-eight healthy adults (14 of each sex) performed knee extensor MVC and plantar flexor MVC at extended and flexed knee positions. Voluntary activation during MVC was assessed using a twitch interpolation technique. The voluntary activation during plantar flexor MVC at the extended knee position was significantly lower (P = 0.020, 95% confidence interval 1.4 to 14.6, Cohen’s d for between-subject design = 0.94) in women (88.3% ± 10.0%) than in men (96.2% ± 6.6%). In contrast, no significant sex differences were shown in the voluntary activation during knee extensor MVC (93.7% ± 5.9% (women) vs. 95.0%  ± 3.9% (men)) and during plantar flexor MVC at the flexed knee position (90.4% ± 12.2% (women) vs. 96.8% ± 5.6% (men)). The voluntary activation during knee extensor MVC was significantly higher (P = 0.001, 95% confidence interval 2.1 to 8.8, Cohen’s d for within-subject design = 0.69) than that during plantar flexor MVC at the extended knee position in women, whereas the corresponding difference was not observed in men. The results revealed that the existence of sex difference in the voluntary activation during MVC depends on joint action and joint angle

In Vivo Function and Evolution of the Eutherian-Specific Pluripotency Marker UTF1

Embryogenesis in placental mammals is sustained by exquisite interplay between the embryo proper and placenta. UTF1 is a developmentally regulated gene expressed in both cell lineages. Here, we analyzed the consequence of loss of the UTF1 gene during mouse development. We found that homozygous UTF1 mutant newborn mice were significantly smaller than wild-type or heterozygous mutant mice, suggesting that placental insufficiency caused by the loss of UTF1 expression in extra-embryonic ectodermal cells at least in part contributed to this phenotype. We also found that the effects of loss of UTF1 expression in embryonic stem cells on their pluripotency were very subtle. Genome structure and sequence comparisons revealed that the UTF1 gene exists only in placental mammals. Our analyses of a family of genes with homology to UTF1 revealed a possible mechanism by which placental mammals have evolved the UTF1 genes.This study was supported in part by the Japanese Ministry of Education, Culture, Sports, Science and Technology (MEXT), and mostly by the Support Program for the Strategic Research Foundation at Private Universities, 2008–2012. This study was performed as a part of the Core Research for Evolutional Science and Technology (CREST) Agency. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Generation of Transgenic Cynomolgus Monkeys Overexpressing the Gene for Amyloid-β Precursor Protein.

Alzheimer\u27s disease (AD) is the most common cause of dementia and understanding its pathogenesis should lead to improved therapeutic and diagnostic methods. Although several groups have developed transgenic mouse models overexpressing the human amyloid-β precursor protein (APP) gene with AD mutations, with and without presenilin mutations, as well as APP gene knock-in mouse models, these animals display amyloid pathology but do not show neurofibrillary tangles or neuronal loss. This presumably is due to differences between the etiology of the aged-related human disease and the mouse models. Here we report the generation of two transgenic cynomolgus monkeys overexpressing the human gene for APP with Swedish, Artic, and Iberian mutations, and demonstrated expression of gene tagged green fluorescent protein marker in the placenta, amnion, hair follicles, and peripheral blood. We believe that these nonhuman primate models will be very useful to study the pathogenesis of dementia and AD. However, generated Tg monkeys still have some limitations. We employed the CAG promoter, which will promote gene expression in a non-tissue specific manner. Moreover, we used transgenic models but not knock-in models. Thus, the inserted transgene destroys endogenous gene(s) and may affect the phenotype(s). Nevertheless, it will be of great interest to determine whether these Tg monkeys will develop tauopathy and neurodegeneration similar to human AD

Comparing national home-keeping and the regulation of translational stem cell applications: an international perspective

A very large grey area exists between translational stem cell research and applications that comply with the ideals of randomised control trials and good laboratory and clinical practice and what is often referred to as snake-oil trade. We identify a discrepancy between international research and ethics regulation and the ways in which regulatory instruments in the stem cell field are developed in practice. We examine this discrepancy using the notion of ‘national home-keeping’, referring to the way governments articulate international standards and regulation with conflicting demands on local players at home. Identifying particular dimensions of regulatory tools – authority, permissions, space and acceleration – as crucial to national home-keeping in Asia, Europe and the USA, we show how local regulation works to enable development of the field, notwithstanding international (i.e. principally ‘western’) regulation. Triangulating regulation with empirical data and archival research between 2012 and 2015 has helped us to shed light on how countries and organisations adapt and resist internationally dominant regulation through the manipulation of regulatory tools (contingent upon country size, the state's ability to accumulate resources, healthcare demands, established traditions of scientific governance, and economic and scientific ambitions)

Effect of raw and purified carbon nanotubes and iron oxide nanoparticles on the growth of wheatgrass prepared from the cotyledons of common wheat (triticum aestivum)

The increase in global production of nanomaterials has raised concern as to their possible effects on plants that could ultimately affect the human population. The effects on the hydroponic growth of wheatgrass of four types of nanomaterials were studied: raw-single walled carbon nanotubes (SWCNTs), purified-SWCNTs, multi walled carbon nanotubes (MWCNTs), and iron oxide nanoparticles (n-FeOx) as a model of the catalyst residue typically present in CNTs. The germination rate (GR), mean germination time (MGT), shoot length, and a visual score of the plants' growth were determined for wheatgrass over the course of two weeks as a function of exposure to the nanomaterials dispersed in either water or THF (as well as appropriate controls). Raw-SWCNTs, MWCNTs, and n-FeOx show little impact suggesting that the catalyst residue (iron oxide) present in CNTs has little effect. Exposure to purified-SWCNTs dispersed in water shows increased GR (and shoot length), while wheatgrass exposed to purified-SWCNT dispersed in THF had retarded GR, suggesting that SWCNTs act as a carrier for adsorbed organic solvents whose effects are detrimental. A similar but lesser effect was observed for MWCNTs. Interestingly raw-SWCNTs showed no solvent effect, suggesting that the reduction of hydrophobicity of the SWCNTs through functionalisation enables the adsorption and subsequent release of harmful organic solvents. The positive effect of purified SWCNTs when dispersed in water is likely a function of their highly hydrophobic nature facilitating enhanced uptake of water