Thyrotropin-releasing hormone does not inhibit lysine vasopressin-induced growth hormone secretion in normal men

Summary In order to establish whether thyrotropin-releasing hormone (TRH) inhibits lysine-vasopressin (LVP)-induced growth hormone (GH) release, six normal men were tested with LVP alone or in combination with TRH. LVP strikingly increased serum GH levels; this response was not altered by TRH. These results indicated that in man TRH is not involved in the control of GH secretion in response to LVP.     

Effects of carmine and carminic acid on embryonic tissue cell cultures

Summary The biological reaction to carmine and carminic acid at cellular level on in vitro cultures was tested and significant variables were controlled. Results suggested that proliferation and metabolism of these cultures were not affected by the 2 stains.     

无氧阈在体育实践及临床医学中的应用

无氧闽(AT)是指在递增运动负荷过程中,人体内的代谢供能方式由有氧代谢为主开始向无氧代谢过渡的临界点。人体在递增负荷运动中,当需氧量超过了当时的供氧水平时,细胞内将以糖元无氧酵解过程使ATP再合成。无氧阈和最大吸氧量(VO_2max)都是评价人体有氧能力及评定心肺病人的生理指标。本文重点论述了无氧阈的含义,测定方法以及在实践中的应用。     

Effects of carmine and carminic acid on embryonic tissue cell cultures

The biological reaction to carmine and carminic acid at cellular level on 'in vitro' cultures was tested and significant variables were controlled. Results suggested that proliferation and metabolism of these cultures were not affected by the 2 stains.     

Thyrotropin-releasing hormone does not inhibit lysine vasopressin-induced growth hormone secretion in normal men

In order to establish whether thyrotropin-releasing hormone (TRH) inhibits lysine-vasopressin (LVP)-induced growth hormone (GH) release, six normal men were tested with LVP alone or in combination with TRH. LVP strikingly increased serum GH levels; this response was not altered by TRH. These results indicate that in man TRH is not involved in the control of GH secretion in response to LVP.     

Fine-scale recombination patterns differ between chimpanzees and humans

Recombination rates seem to vary extensively along the human genome. Pedigree analysis suggests that rates vary by an order of magnitude when measured at the megabase scale, and at a finer scale, sperm typing studies point to the existence of recombination hotspots. These are short regions (1-2 kb) in which recombination rates are 10-1,000 times higher than the background rate. Less is known about how recombination rates change over time. Here we determined to what degree recombination rates are conserved among closely related species by estimating recombination rates from 14 Mb of linkage disequilibrium data in central chimpanzee and human populations. The results suggest that recombination hotspots are not conserved between the two species and that recombination rates in larger (50 kb) genomic regions are only weakly conserved. Therefore, the recombination landscape has changed markedly between the two species.     

FACL4, encoding fatty acid-CoA ligase 4, is mutated in nonspecific X-linked mental retardation

X-linked mental retardation (XLMR) is an inherited condition that causes failure to develop cognitive abilities, owing to mutations in a gene on the X chromosome. The latest XLMR update lists up to 136 conditions leading to 'syndromic', or 'specific', mental retardation (MRXS) and 66 entries leading to 'nonspecific' mental retardation (MRX). For 9 of the 66 MRX entries, the causative gene has been identified. Our recent discovery of the contiguous gene deletion syndrome ATS-MR (previously known as Alport syndrome, mental retardation, midface hypoplasia, elliptocytosis, OMIM #300194), characterized by Alport syndrome (ATS) and mental retardation (MR), indicated Xq22.3 as a region containing one mental retardation gene. Comparing the extent of deletion between individuals with ATS-MR and individuals with ATS alone allowed us to define a critical region for mental retardation of approximately 380 kb, containing four genes. Here we report the identification of two point mutations, one missense and one splice-site change, in the gene FACL4 in two families with nonspecific mental retardation. Analysis of enzymatic activity in lymphoblastoid cell lines from affected individuals of both families revealed low levels compared with normal cells, indicating that both mutations are null mutations. All carrier females with either point mutations or genomic deletions in FACL4 showed a completely skewed X-inactivation, suggesting that the gene influences survival advantage. FACL4 is the first gene shown to be involved in nonspecific mental retardation and fatty-acid metabolism.