A new set of DNA macrochips for the yeast Saccharomyces cerevisiae: features and uses.

The yeast Saccharomyces cerevisiae has been widely used for the implementation of DNA chip technologies. For this reason and due to the extensive use of this organism for basic and applied studies, yeast DNA chips are being used by many laboratories for expression or genomic analyses. While membrane arrays (macroarrays) offer several advantages, for many laboratories they are not affordable. Here we report that a cluster of four Spanish molecular-biology yeast laboratories, with relatively small budgets, have developed a complete set of probes for the genome of S. cerevisiae. These have been used to produce a new type of macroarray on a nylon surface. The macroarrays have been evaluated and protocols for their use have been optimized.     

Biomarkers of exposure,effect, and susceptibility in workers exposed to chloronitrobenzenes

Biomonitoring methods were applied to workers exposed to high levels of chloronitrobenzenes. The external dose, internal dose, biologically effective dose, and biological effects were determined. Individual susceptibility was assessed by analyzing genetic polymorphisms of glutathione S-transferases M1, P1 and T1, and N-acetyltransferases 1 and 2. When the markers of exposure and susceptibility were compared with the frequency of chromosomal aberrations, clinical blood and urine parameters, and health effects typical of chloronitrobenzenes exposure, only a few of the comparisons were statistically significant. A statistically significantly higher frequency of chromosomal aberrations was detected in workers with a high level of hemoglobin-adducts.     

Synthesis of habitat restoration impacts on young-of-the-year salmonids in boreal rivers

Reviews in Fish Biology and Fisheries - River restoration offers the potential to enhance biological integrity, often measured as fish population changes. We used a meta-analytical approach to...     

YPI1 and SDS22 proteins regulate the nuclear localization and function of yeast type 1 phosphatase Glc7

We have recently characterized Ypi1 as an inhibitory subunit of yeast Glc7 PP1 protein phosphatase. In this work we demonstrate that Ypi1 forms a complex with Glc7 and Sds22, another Glc7 regulatory subunit that targets the phosphatase to substrates involved in cell cycle control. Interestingly, the combination of equimolar amounts of Ypi1 and Sds22 leads to an almost full inhibition of Glc7 activity. Because YPI1 is an essential gene, we have constructed conditional mutants that demonstrate that depletion of Ypi1 leads to alteration of nuclear localization of Glc7 and cell growth arrest in mid-mitosis with aberrant mitotic spindle. These phenotypes mimic those produced upon inactivation of Sds22. The fact that progressive depletion of either Ypi1 or Sds22 resulted in similar physiological phenotypes and that both proteins inhibit the phosphatase activity of Glc7 strongly suggest a common role of these two proteins in regulating Glc7 nuclear localization and function.     

Innate Sensing through Mesenchymal TLR4/MyD88 Signals Promotes Spontaneous Intestinal Tumorigenesis

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Blimp1 Prevents Methylation of Foxp3 and Loss of Regulatory T Cell Identity at Sites of Inflammation

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The influenza hemagglutinin precursor as an acid-sensitive probe of the biosynthetic pathway.

The hemagglutinin of influenza virus (HA), an acid-activated membrane fusion protein, is synthesized in the endoplasmic reticulum and transported through the Golgi complex to the cell surface of infected cells as an uncleaved, fusion-incompetent precursor, HA0. The mature, proteolytically activated HA is known to undergo a rapid, irreversible, acid-induced conformational change which mediates membrane fusion and virus penetration. On the basis of antigenic modifications and the acquisition of trypsin susceptibility, we demonstrate here that HA0, while unable to cause fusion, is acid sensitive. It undergoes irreversible conformational changes quite similar to those of HA at mildly acidic pH (pH less than 6.0). The ectodomain of HA0 does not, however, acquire hydrophobic properties and the changes occur in a less concerted manner (the pH dependence is much broader and the rate of conversion slower). These differences are likely to account for the inability of acid-treated HA0 to trigger membrane fusion. It was shown, moreover, that HA0 acquired its acid-sensitive properties immediately following trimerization in the endoplasmic reticulum. Since HA0 did not convert to the acid form at any point during its intracellular transport, we concluded that the trans-Golgi compartment, known to be more acidic than the cytosol and involved in constitutive membrane transport, is not likely to have a pH less than 6.0.     

Kinetic,Energetic, and Mechanical Differences between Dark-State Rhodopsin and Opsin

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Highlights? Mapping the stability of opsin from the rod outer segment of the mouse eye ? Compared to dark-state rhodopsin opsin increases mechanical stability and rigidity ? Compared to dark-state rhodopsin opsin reduces lifetime and free energy ? Compared to dark-state rhodopsin opsin is pliable and adopts alternate conformations     

Responses of FEV6, FVC,and FET to inhaled bronchodilator in the adult general population

Background

The assessment of bronchodilator-induced change in forced vital capacity (FVC) is dependent on forced expiratory time (FET) in subjects with airflow limitation. Limited information is available on the concurrent responses of FVC, forced expiratory volume in six seconds (FEV₆), and FET in the bronchodilation test among patients with obstructive airways disease or in the general population. The aim of this study was to assess the changes in FEV₆, FVC, and FET, and their relationships in a standardized bronchodilation test in the general population.

Methods

We studied bronchodilation response in a general adult population sample of 628 individuals (260 men, 368 women) with flow-volume spirometry. The largest FVC, the corresponding FET and the largest FEV₆ both at the baseline and after 0.4 mg of inhaled salbutamol were selected for analysis.

Results

After administration of salbutamol FEV₆ decreased on average -13.4 (95% CI -22.3 to -4.5) ml or -0.2% (-0.4% to 0.0%) from the baseline. The 95^th percentile of change in FEV₆ was 169.1 ml and 5.0%. FVC decreased on average -42.8 (-52.4 to -33.3) ml or -1.0% (-1.2% to -0.7%). Concurrently FET changed on average -0.2 (-0.4 to 0.0) seconds or 0.4% (-1.4% to 2.3%). There were four subjects with an increase of FVC over 12% and only one of these was associated with prolonged FET after salbutamol. Changes in FEV₆ and FVC were more frequently positive in subjects with reduced FEV₁/FVC in baseline spirometry.

Conclusion

In general adult population, both FEV₆ and FVC tended to decrease, but FET remained almost unchanged, in the bronchodilation test. However, those subjects with signs of airflow limitation at the baseline showed frequently some increase of FEV₆ and FVC in the bronchodilation test without change in FET. We suggest that FEV₆ could be used in assessment of bronchodilation response in lieu of FVC removing the need for regulation of FET during bronchodilation testing.     

Longitudinal and seasonal variation of the benthic macroinvertebrate community and biotic indices in an undisturbed Pyrenean river

The present work aims to analyze the spatio-temporal variability in benthic macroinvertebrate assemblages and biotic indices in an undisturbed and unpolluted Pyrenean river. Samples were collected seasonally over 2 year-cycles (2001–2002) at fifteen sampling sites along the Erro River (Ebro River Basin, Spain) during a exhaustive biomonitoring program following the IBMWP–IASPT scoring system protocol routinely applied in Iberia. Despite absolute values of the biotic indices showed high spatio-temporal variation, the IBMWP–IASPT scoring system proved useful because water quality classes were consistent throughout seasons and years as well as along-river. The original macroinvertebrate families’ presence/absence data matrix was reduced in a number of ways to conduct different statistical procedures in order to detect and separate the underlying near-natural spatial and temporal gradients of the assemblage composition in the Erro River. Along-river, spatial variation of the macroinvertebrate community composition was well assessed by similarity analysis, which clearly detected physical features on the river (drought-affected reach, gorge, towns and flow gauging weirs). Categorical principal component analysis (CATPCA) synthesized and jointly ordered macroinvertebrate samples in a spatio-temporal gradient in the factorial map defined by the first two principal components providing a parsimonious way to assess the assemblages’ variation. These two variation gradients throughout the macroinvertebrate families’ occurrence data were subsequently confirmed separately by several correspondence analyses and revealed additional information, as the representative families for each sampling site group and season could be identified. Furthermore, these spatio-temporal gradients were discussed and put in relation with changes in the aquatic habitat (water temperature, conductivity, total dissolved solids, water velocity, channel width, canopy cover, etc.). The near-natural functioning of the Erro River promoted us to emphasize that conservation efforts should aim to maintain the free-flowing as a permanent source of variability.