Phagocytic function in cyclists: correlation with catecholamines and cortisol.

Flow cytometer measurements were made of the basal variations in peripheral blood functional monocytes and granulocytes over the course of a training season (January to November) of a cycling team. Parallel determinations were made of plasma concentration of catecholamines (chromatography) and cortisol (RIA) in a search for neuroendocrine markers. The results showed the greatest phagocytic capacity to occur in the central months (March, May, and July), coinciding with the greatest number and highest level of competitive events with good correlation with a peak in epinephrine during these months (r(2) = 0.998 for monocytes and r(2) = 0.674 for granulocytes). No good correlations were found between phagocytosis and norepinephrine or cortisol. The highest values for phagocytosis and epinephrine concentration were found in May. These results suggest that blood epinephrine concentration could be a good neuroendocrine marker of sportspeople's phagocytic response.     

Identifying essential genes in bacterial metabolic networks with machine learning methods

Background  

Identifying essential genes in bacteria supports to identify potential drug targets and an understanding of minimal requirements for a synthetic cell. However, experimentally assaying the essentiality of their coding genes is resource intensive and not feasible for all bacterial organisms, in particular if they are infective.     

State-of-the art data normalization methods improve NMR-based metabolomic analysis

Extracting biomedical information from large metabolomic datasets by multivariate data analysis is of considerable complexity. Common challenges include among others screening for differentially produced metabolites, estimation of fold changes, and sample classification. Prior to these analysis steps, it is important to minimize contributions from unwanted biases and experimental variance. This is the goal of data preprocessing. In this work, different data normalization methods were compared systematically employing two different datasets generated by means of nuclear magnetic resonance (NMR) spectroscopy. To this end, two different types of normalization methods were used, one aiming to remove unwanted sample-to-sample variation while the other adjusts the variance of the different metabolites by variable scaling and variance stabilization methods. The impact of all methods tested on sample classification was evaluated on urinary NMR fingerprints obtained from healthy volunteers and patients suffering from autosomal polycystic kidney disease (ADPKD). Performance in terms of screening for differentially produced metabolites was investigated on a dataset following a Latin-square design, where varied amounts of 8 different metabolites were spiked into a human urine matrix while keeping the total spike-in amount constant. In addition, specific tests were conducted to systematically investigate the influence of the different preprocessing methods on the structure of the analyzed data. In conclusion, preprocessing methods originally developed for DNA microarray analysis, in particular, Quantile and Cubic-Spline Normalization, performed best in reducing bias, accurately detecting fold changes, and classifying samples.

     

Toll-like receptor 4 deficiency: Smaller infarcts,but nogain in function

Backgound  

It has been reported that Toll-like receptor 4 (TLR4) deficiency reduces infarct size after myocardial ischemia/reperfusion (MI/R). However, measurement of MI/R injury was limited and did not include cardiac function. In a chronic closed-chest model we assessed whether cardiac function is preserved in TLR4-deficient mice (C3H/HeJ) following MI/R, and whether myocardial and systemic cytokine expression differed compared to wild type (WT).     

Spatial productivity variations during formation of sapropels S5 and S6 in the Mediterranean Sea: evidence from Ba contents

We investigated five time-equivalent core sections (180-110 kyr BP) from the Balearic Sea (Menorca Rise), the easternmost Levantine Basin and southwest, south, and southeast of Crete to reconstruct spatial patterns of productivity during deposition of sapropels S5 and S6 in the Mediterranean Sea. Our indicators are Ba, total organic carbon and carbonate contents. We found no indications of Ba remobilization within the investigated core intervals, and used the accumulation rate of biogenic Ba to compute paleoproductivity. Maximum surface water productivity (up to 350 g C/m²/yr) was found during deposition of S5 (isotope stage 5e) but pronounced spatial variability is evident. Coeval sediment intervals in the Balearic Sea show very little productivity change, suggesting that chemical and biological environments in the eastern and western Mediterranean basins were decoupled in this interval. We interpret the spatial variability as the result of two different modes of nutrient delivery to the photic zone: river-derived nutrient input and shoaling of the pycnocline/nutricline to the photic zone. The productivity increase during the formation of S6 was moderate compared to S5 and had a less marked spatial variability within the study area of the eastern Mediterranean Sea. Given that S6 formed during a glacial interval, glacial boundary conditions such as high wind stress and/or cooler surface water temperatures apparently favored lateral and vertical mixing and prevented the development of the spatial gradients within the Eastern Mediterranean Sea (EMS) observed for S5. A non-sapropel sediment interval with elevated Ba content and depleted ¹⁸O/¹⁶O ratios in planktonic foraminifer calcite was detected between S6 and S5 that corresponds to the weak northern hemisphere insolation maximum at 150 kyr. At this time, productivity apparently increased up to five times over surrounding intervals, but abundant benthic fauna show that the deep water remained oxic. Following our interpretation, the interval denotes a failed sapropel, when a weaker monsoon did not force the EMS into permanent stratification. The comparison of interglacial and glacial sapropels illustrates the relevance of climatic boundary conditions in the northern catchment in determining the facies and spatial variability of sapropels within the EMS.     

Developmental ocular disease of raptors

Sixteen raptors, including one eagle, two falcons, five hawks and eight owls, were found to have developmental ocular lesions. The most common lesion was microphthalmia. Other findings included cataract, microphakia, retinal dysplasia, malformation of the ciliary body, choroid and pecten, and lentoid formation. Specific causes for these lesions could not be determined. It is hypothesized that developmental ocular disease probably is more common than available reports indicate.