Androgen’s effects in female

The metabolic effects of androgens and their underlying mechanisms in females have been revealed by recent studies. An excess of androgens can have adverse effects on feeding behavior and metabolic functions and induce metabolic disorders / diseases, such as obesity, insulin resistance, and diabetes, in women and experimental animals of reproductive age. Interestingly, these effects of androgens are not observed in ovariectomized animals, indicating that their effects might be dependent on the estrogen milieu. Central and peripheral mechanisms, such as alterations in the activity of hypothalamic factors, reductions in energy expenditure, skeletal muscle insulin resistance, and β-cell dysfunction, might be related to these androgens’ effects

Biotin levels in blood and follicular fluid

It has been shown that biotin, a water-soluble vitamin (B7), plays roles in reproductive functions, such as oocyte maturation and embryo development, in experimental animals. On the other hand, little is known about the clinical effects of biotin on human reproduction. In this study, serum and follicular fluid biotin levels were measured in patients who underwent in vitro fertilization / intracytoplasmic sperm injection (IVF / ICSI), and their associations with reproductive outcomes were evaluated. As a result, biotin was detected in follicular fluid, as well as serum, and the biotin levels of follicular fluid were found to be positively correlated with those of serum. The biotin levels of serum were higher than those of follicular fluid, suggesting that biotin may be taken up into the follicular fluid from the blood. Although serum and follicular fluid biotin levels tended to be higher in pregnant patients than in non-pregnant patients, these data did not show the significant statistical difference. These findings indicate that biotin does not contribute to the maintenance of oocyte quality, and hence, it does not increase fertilization and pregnancy rates

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Root growth of Pinus thunbergii seedlings related to the restoration of Tohoku region coastal forests after the disastrous tsunami

Due to the disastrous tsunami which occurred along the pacific coastline of eastern Japan, 3660 ha of Pinus thunbergii Parlatore (Japanese black pine) coastal forests were heavily damaged. To restore and recover the functions of these coastal forests, artificial growth berms are being constructed to secure enough space for root growth, especially in the vertical direction. However, due to the use of heavy machinery, the surface soil of the growth berm was packed down and significantly compacted. Compacted soil results in hard soil and is often reported to negatively affect root growth of seedlings. Additionally, in some cases, waterlogging after rainfall is not promptly discharged due to low soil permeability and drainage. As oxygen availability becomes severely limited under waterlogging, this can also negatively affect root growth. Considering these problems, studies have been made to elucidate effects of soil compaction and waterlogging on root growth of P. thunbergii seedlings and broadleaved species which are new candidates for introduction to coastal forests. Furthermore, at some of the restoration sites, plowing of the surface soil is being experimentally done to soften the surface soil and improve drainage. Here, we review results obtained from several field surveys and pot experiments which suggest important key points to realize the healthy root growth of P. thunbergii seedlings at coastal restoration sites