A putative GDP–GTP exchange factor is required for development of the excretory cell in Caenorhabditis elegans

The Caenorhabditis elegans excretory cell extends tubular processes, called canals, along the basolateral surface of the epidermis. Mutations in the exc-5 gene cause tubulocystic defects in this canal. Ultrastructural analysis suggests that exc-5 is required for the proper placement of cytoskeletal elements at the apical epithelial surface. exc-5 encodes a protein homologous to guanine nucleotide exchange factors and contains motif architecture similar to that of FGD1, which is responsible for faciogenital dysplasia. exc-5 interacts genetically with mig-2, which encodes Rho GTPase. These results suggest that EXC-5 controls the structural organization of the excretory canal by regulating Rho family GTPase activities.     

Increased frequency of 6-thioguanine-resistant peripheral blood lymphocytes in Werner syndrome patients

Summary The frequency of spontaneous 6-thioguanine (TG)-resistant peripheral blood lymphocytes in five unrelated Werner syndrome (WS) patients was determined using an autoradiographic labeling assay. The average frequency of TG-resistant lymphocytes was eightfold higher in WS patients than in sex- and age-matched normal control donors. This finding and previous identification of increased spontaneous chromosomal rearrangements and deletions in WS cells or cell lines suggest that WS is a human genomic instability or mutator syndrome.     

Performance of a cell recycle bubble column fermentor with a membrane filter module for continuous vinegar production

The steady-state performance of a bubble column combined with a membrane filter module for cell separation and recycle is investigated numerically in the case of vinegar fermentation. The one-dimensional dispersion model for describing the longitudinal mixing of the liquid phase is employed. Kinetic expressions and their parameter values are taken from the available literature. Several characteristics of this fermentor system namely the concentration profiles of cells, substrate and product, the viability of viable cells relative to total cells, the washout condition for cells and the productivity of acetic acid are discussed. The average cell viability in the whole column and the critical dilution rate for washout are presented as equations. Low levels of the axial mixing are found to enhance the vinegar productivity. The optimum dilution rate giving the maximum productivity is determined and both are shown as figures with the Peclet number, the recycle ratio and the bleed ratio as parameters.     

The Incidence of R Factors in Bordetella bronchiseptica Isolated from Pigs

Bordetella bronchiseptica strains isolated from the nasal cavities of young pigs in Japan from 1969 to 1972 were surveyed for drug resistance and distribution of R factors. Of 304 strains examined, 71 (23%) were resistant to either one or more of following three drugs, streptomycin (SM), sulfadimethoxine (SA), and aminobenzyl penicillin (APC). Triple (SM.SA.APC)-resistance was most frequent among these resistant strains. Strains of double (SM. SA)- or single (SM)- and (SA)-resistance were also isolated, but were very few in numbers. Of the 71 drug-resistant strains, 61 (86%) were found to carry R factors which were capable of conjugal transfer. All of these R factors had the triple (SM.SA.APC)-resistant markers and were identified as fi^– (no fertility inhibition) type. The (SM.SA.APC)-resistant strains carrying R factors had been isolated from pigs reared on various farms in different districts, and consequently the prevalence of B. bronchiseptica strains carrying R factors was considered to be relatively wide-spread in young pigs.     

Syntheses of all eight stereoisomers of conidendrin

ABSTRACT

All eight stereoisomers of conidendrin were synthesized from (1 R,2 S,3 S)-1-(4-benzyloxy-3-methoxyphenyl)-3-(4-benzyloxy-3-methoxybenzyl)-2- hydroxymethyl-1,4-butanediol ((+)-4) and its enantiomer with high optical purity. The configurations at 4-positions of the conidendrin stereoisomers were constructed by intramolecular Friedel-Crafts reaction of protected 4. After conversion to tetrahydronaphthalene intermediate 7a, the 2- and 3-position of tetrahydronaphthalene structure 7a were converted to 3a- and 9a-position of (+)-α-conidendrin (3a), respectively. By the epimerization process of 2- or 3-position of 7a, the other diastereomers were obtained. All enantiomers were also synthesized from (?)-4.     

Microbial Production of d-Arabitol by n-Alkane-grown Candida tropicalis

In the course of study on citric acid fermentation by Candida tropicalis KY6224, in which n-alkane mixture (C–12 to C–15) was used as the sole source of carbon, we found that a arabitollike substance was accumulated when the medium-pH was controlled at low level (3.0 to 4.0). This substance was isolated in crystalline forms and identified as d-arabitol.

d-Arabitol production was also observed with ethanol, acetic acid and glucose as the sole source of carbon. Important factors for efficient production of d-arabitol were keeping the medium-pH at low-level (3.0 to 4.0) and the concentration of NaCl or KCl at high level (1 to 5%). This strain produced 75 mg/ml of d-arabitol in 120 hr incubation under optimal culture conditions; this corresponds to 50 % of n-alkane consumed.     

Production of Erythritol by n-Alkane-grown Yeasts

In the course of study on citric acid fermentation by Candida zeylanoides, in which n-alkane (a mixture of C–12 to C–15) was used as the sole source of carbon, we found that a polyol-like substance was accumulated when the medium-pH fell down to below 4.0. This was isolated in crystalline forms and identified as meso-erythritol. Comparing erythritol production among fifty yeast strains, Candida zeylanoides, particularly its glycerol-requiring mutant KY 6166, was found to be an excellent producer.

Erythritol production was also observed with ethanol or acetic acid as the sole carbon source but not with glucose. An efficient condition for large production of erythritol was to keep the medium-pH at low level (2.5 to 4.0) and the concentration of NaCl or KCl at high level (1 to 3%). Under conditions established in this work, more than 55 mg/ml of erythritol was successfully produced in 120 hr incubation in 300-ml flasks, which corresponded to 55% of the alkane used.     

Effects of aerobic exercise on metabolic syndrome improvement in response to weight reduction

Objective: The objective was to test effects of aerobic exercise training on metabolic syndrome (MetSyn) improvement in response to weight reduction. Research Methods and Procedures: A total of 459 overweight and obese women (age, 49 ± 9 years; BMI, 28 ± 3 kg/m²) were recruited for a baseline examination to test the relationship between cardiorespiratory fitness and metabolic syndrome prevalence; among these, 67 subjects with MetSyn were treated with 14‐week weight‐loss programs, which included low‐calorie diet and aerobic exercise. The MetSyn was defined according to the Examination Committee of Criteria for “Metabolic Syndrome” in Japan. Maximal oxygen uptake (V?o _2max) during a maximal cycling test was measured as an index of cardiorespiratory fitness at baseline and after the intervention. Results: In the baseline examination, age‐ and BMI‐adjusted odds ratios for MetSyn prevalence in the low, middle, and upper thirds of V?o _2max were 1.0 (referent), 0.50 (95% confidence interval, 0.26 to 0.95), and 0.39 (95% confidence interval, 0.14 to 0.96), respectively (linear trend, p = 0.02). The adjusted odds ratios for MetSyn improvement in the two interventions with diet alone and diet plus exercise were 1.0 and 3.68 (95% confidence interval, 1.02 to 17.6; p = 0.04), respectively. Discussion: These results suggest that adding aerobic exercise training to a dietary weight‐reduction program further improves MetSyn (adjusted odds ratio, 3.68) in obese women, compared with diet alone. Further studies on an association between V?o _2max change and MetSyn improvement are needed.     

Personalized medicine and proteomics: lessons from non-small cell lung cancer

Personalized medicine allows the selection of treatments best suited to an individual patient and disease phenotype. To implement personalized medicine, effective tests predictive of response to treatment or susceptibility to adverse events are needed, and to develop a personalized medicine test, both high quality samples and reliable data are required. We review key features of state-of-the-art proteomic profiling and introduce further analytic developments to build a proteomic toolkit for use in personalized medicine approaches. The combination of novel analytical approaches in proteomic data generation, alignment and comparison permit translation of identified biomarkers into practical assays. We further propose an expanded statistical analysis to understand the sources of variability between individuals in terms of both protein expression and clinical variables and utilize this understanding in a predictive test.