BRCA2 gene: a candidate for clinical testing in familial colorectal cancer type X

Familial colorectal cancer type X (FCCX) encompasses a group of families with dominant inheritance pattern of colorectal cancer (CRC) but no alteration in any known CRC susceptibility gene. Therefore, the explanation of their susceptibility is a priority to offer an accurate genetic counseling. We screened the 27 coding exons and exon-intron boundaries of BRCA2 in 48 FCCX probands. We identified 29 variants including a frameshift mutation. Deleterious variant c.3847_3848delGT p.(Val1283Lysfs*2) showed cosegregation with disease as well as loss of heterozygosity (LOH) in CRC tumor DNA. This is the first evidence of germline BRCA2 pathogenic mutation associated with CRC risk. Furthermore, missense variants c.502C>A p.(Pro168Thr), c.5744C>T p.(Thr1915Met) and c.7759C>T p.(Leu2587Phe) were proposed as candidate risk alleles based on cosegregation, LOH tumor analysis and in silico testing.

Plasma ghrelin levels in healthy elderly volunteers: the levels of acylated ghrelin in elderly females correlate positively with serum IGF-I levels and bowel movement frequency and negatively with systolic blood pressure

Aging is associated with a decrease in growth hormone (GH) secretion, appetite and energy intake. As ghrelin stimulates both GH secretion and appetite, reductions in ghrelin levels may be involved in the reductions in GH secretion and appetite observed in the elderly. However, only preliminary studies have been performed on the role of ghrelin in elderly subjects. In this study, we sought to clarify the physiologic implications of the age-related alterations in ghrelin secretion by determining plasma ghrelin levels and other clinical parameters in healthy elderly subjects. Subjects were > or = 65 years old, corresponding to the SENIEUR protocol, had not had a resection of the upper gastrointestinal tract and had not been treated with hormones. One hundred and five volunteers (49 men and 56 women) were admitted to this study (73.4 +/- 6.3 years old). Plasma levels of acylated ghrelin in elderly female subjects positively correlated with serum IGF-I levels and bowel movement frequency and negatively with systolic blood pressure. In elderly men, desacyl ghrelin levels correlated only weakly with bowel movement frequency. These findings suggest that the plasma levels of the acylated form of ghrelin may influence the age-related alterations in GH/IGF-I regulation, blood pressure and bowel motility. These observational associations warrant further experimental studies to clarify the physiologic significance of these effects.

Novel amino acid metabolite produced by Streptomyces sp.: I. Taxonomy, isolation, and structural elucidation

A strain of streptomycete isolated from a soil sample was found to produce a novel amino acid metabolite. The compound was purified from the culture fluid by chromatography, using cation exchange resin, a synthetic adsorbent, and finally by preparative HPLC with a reverse-phase column. The structure of the compound was established as N(delta)-(5-methyl-4-oxo-2-imidazolin-2-yl)-L-ornithine on the basis of an analysis of the spectral data and chemical degradation. This was confirmed by comparing the NMR spectrum of the metabolite with that of the compound synthesized by treating methylglyoxal and N(alpha)-acetyl-L-arginine. The substance did not show any antimicrobial activity against bacteria, fungi and yeasts by the agar plate method, but exhibited a weak preventive effect on cucumber mildew disease in a pot test.

Isolation of 203mercury-induced metallothionein in rat kidney by direct connection of HPLC to a beta radioactivity detector

Rat kidney 203Hg-induced metallothionein (HgMT) was separated on a high performance liquid chromatograph equipped with a gel permeation column and an on-line beta radioactivity detector, in order to obtain the simultaneous measurements of renal MT by UV detection and MT-associated 203Hg by a beta radioactivity detector. Metallothionein was separated in three major species by both UV detection at 254 nm and 203Hg detection, probably due to the presence of mercury and copper. A standard curve was prepared which demonstrated excellent linear correlation between the integrated HgMT peaks area and the quantity of HgMT injected into the column. In contrast to the results with the gel permeation column above mentioned, rat kidney HgMT was separated in four peaks by reversed-phase height performance liquid chromatography.