Neighborhood Socioeconomic Status in Relation to 10‐Year Weight Gain in the Black Women's Health Study

We prospectively assessed the association of neighborhood socioeconomic status (SES) with 10‐year weight change and with incident obesity among 48,359 women in the Black Women's Health Study (BWHS). Lower neighborhood SES was significantly associated with 10‐year weight gain after adjustment for individual SES and behavioral variables, such as physical activity and caloric intake. Low neighborhood SES was also associated with increased incidence of obesity during 10 years of follow‐up among women of normal weight at baseline (BMI <25 kg/m²). The associations were most evident among BWHS participants who had graduated from college. These prospective data suggest that lower neighborhood SES contributes to overweight and obesity in African‐American women.     

Whole chromosome loss and associated breakage–fusion–bridge cycles transform mouse tetraploid cells

Whole chromosome gains or losses (aneuploidy) are a hallmark of ~70% of human tumors. Modeling the consequences of aneuploidy has relied on perturbing spindle assembly checkpoint (SAC) components, but interpretations of these experiments are clouded by the multiple functions of these proteins. Here, we used a Cre recombinase‐mediated chromosome loss strategy to individually delete mouse chromosomes 9, 10, 12, or 14 in tetraploid immortalized murine embryonic fibroblasts. This methodology also involves the generation of a dicentric chromosome intermediate, which subsequently undergoes a series of breakage–fusion–bridge (BFB) cycles. While the aneuploid cells generally display a growth disadvantage in vitro, they grow significantly better in low adherence sphere‐forming conditions and three of the four lines are transformed in vivo, forming large and invasive tumors in immunocompromised mice. The aneuploid cells display increased chromosomal instability and DNA damage, a mutator phenotype associated with tumorigenesis in vivo. Thus, these studies demonstrate a causative role for whole chromosome loss and the associated BFB‐mediated instability in tumorigenesis and may shed light on the early consequences of aneuploidy in mammalian cells.     

Nonsense mutations in the amylomaltase gene and other loci of Streptococcus pneumoniae

Summary Maltose-negative mutations in the amylomaltase gene of Streptococcus pneumoniae were examined for the presence of nonsense mutations. Out of 28 single-site mutants tested, 3 were shown to be suppressible by an amber suppressor previously found by Gasc et al. (1979). In the presence of the suppressor these mutants manifested 10–30% of wild type amylomaltase activity. In addition to the amylomaltase governed by malM, and the maltosaccharide phosphorylase governed by malP (which maps to the side of malM distal to the regulatory gene, malR), a new maltose-inducible protein, governed by another gene, malX, was observed in gel electrophoretic patterns. The malX gene maps on the side of malM proximal to the malR gene. The approximate molecular weights of the amylomaltase, phosphorylase and malX polypeptides are 62,000, 87,000 and 50,000, respectively. There appear to be no polar effects of the nonsense mutations in the malM gene on synthesis of the gene products of either malP or malX. In a search for nonsense mutants at other loci, one was found in the end gene, which governs the major endonuclease, a membrane enzyme. None were detected among 5 mismatch-repair defective hex mutants analyzed.     

Digoxigenin as a probe label for in situ hybridization on skeletal tissues.

Summary Non-specific staining was encountered using digoxigenin-labelled cDNA probes forin situ hybridization on sections of skeletal tissues. This staining was most pronounced in cartilaginous matrices. Experimental procedures indicate that the background staining is caused by antibody-binding to hydrophobic sites in the tissues revealed by proteolytic permeabilization. A protocol for minimizing this background is described.     

CGRP antagonists and capsaicin on celiac ganglia partly prevent postoperative gastric ileus

The role of capsaicin-sensitive pathways and CGRP in postoperative gastric ileus was investigated. Abdominal surgery was performed under enflurane anesthesia, and 5 min later, the 20-min rate of gastric emptying was measured by the phenol red method in conscious rats. Surgery inhibited gastric emptying by 76–83% compared with rats receiving anesthesia alone. Capsaicin on the celiac/mesenteric ganglia (10–21 days before) reduced gastric ileus by 33 ± 8%, whereas perivagal capsaicin had no effect. The IV CGRP-induced inhibition of gastric emptying was completely reversed by the CGRP antagonist, CGRP(8–37) (30 μg, IV); CGRP(8–37) (15, 30, or 60 μg) or CGRP monoclonal antibody #4901 (2 mg protein) decreased the inhibition of gastric emptying by 11 ± 7%, 51 ± 13%, 47 ± 3%, and 45 ± 17%, respectively. These results indicate that CGRP and splanchnic capsaicin-sensitive afferents are involved in mediating part of the gastric ileus observed immediately after abdominal surgery.     

Sur la presence de deux isoenzymes de la phenylalanine-ammoniac-lyase chez Aesculus hippocastanum

By using the normal techniques of protein separation, two forms of PAL with different properties have been separated from the glandular tissue of Aesculus hippocastanum. A hypothesis is proposed for correlating the isoenzyme activities with the accumulation of flavonoid compounds and benzoic acids in the trichomes.