Selected anthropometric variables and aerobic fitness as predictors of cardiovascular disease risk in children

The aim of this study was to assess the suitability of body mass index, waist circumference, waist-to-height ratio and aerobic fitness as predictors of cardiovascular risk factor clustering in children. A cross-sectional study was conducted with 290 school boys and girls from 6 to 10 years old, randomly selected. Blood was collected after a 12-hour fasting period. Blood pressure, waist circumference (WC), height and weight were evaluated according to international standards. Aerobic fitness (AF) was assessed by the 20-metre shuttle-run test. Clustering was considered when three of these factors were present: high systolic or diastolic blood pressure, high low-density lipoprotein (LDL) cholesterol, high triglycerides, high plasma glucose, high insulin concentrations and low high-density lipoprotein (HDL) cholesterol. A ROC curve identified the cut-off points of body mass index (BMI), WC, waist-to-height ratio (WHtR) and AF as predictors of risk factor clustering. BMI, WC and WHR resulted in significant areas under the ROC curves, which was not observed for AF. The anthropometric variables were good predictors of cardiovascular risk factor clustering in both sexes, whereas aerobic fitness should not be used to identify cardiovascular risk factor clustering in these children.     

Extremely high Tp53 mutation load in esophageal squamous cell carcinoma in Golestan Province, Iran

Background

Golestan Province in northeastern Iran has one of the highest incidences of esophageal squamous cell carcinoma (ESCC) in the world with rates over 50 per 100,000 person-years in both sexes. We have analyzed TP53 mutation patterns in tumors from this high-risk geographic area in search of clues to the mutagenic processes involved in causing ESCC.

Methodology/Principal Findings

Biopsies of 119 confirmed ESCC tumor tissue from subjects enrolled in a case-control study conducted in Golestan Province were analyzed by direct sequencing of TP53 exons 2 through 11. Immunohistochemical staining for p53 was carried out using two monoclonal antibodies, DO7 and 1801. A total of 120 TP53 mutations were detected in 107/119 cases (89.9%), including 11 patients with double or triple mutations. The mutation pattern was heterogeneous with infrequent mutations at common TP53 “hotspots” but frequent transversions potentially attributable to environmental carcinogens forming bulky DNA adducts, including 40% at bases known as site of mutagenesis by polycyclic aromatic hydrocarbons (PAHs). Mutations showed different patterns according to the reported temperature of tea consumption, but no variation was observed in relation to ethnicity, tobacco or opium use, and alcoholic beverage consumption or urban versus rural residence.

Conclusion/Significance

ESCC tumors in people from Golestan Province show the highest rate of TP53 mutations ever reported in any cancer anywhere. The heterogeneous mutation pattern is highly suggestive of a causative role for multiple environmental carcinogens, including PAHs. The temperature and composition of tea may also influence mutagenesis.     

Comparative Evaluation Of Raman Spectroscopy At Different Wavelengths For Extremophile Exemplars

Raman spectra have been obtained for extremophiles from several geological environments; selected examples have been taken from hot and cold deserts comprising psychrophiles, thermophiles and halophiles. The purpose of this study is the assessment of the effect of the wavelength of the laser excitation on the ability to determine unique information from the Raman spectra about the specificity of detection of biomolecules produced as a result of the survival strategies adopted by organisms in extreme terrestrial environments. It was concluded that whereas FT-Raman spectroscopy at 1064 nm gave good quality results the time required to record the data was relatively large compared with other wavelengths of excitation but that better access to the CH stretching region for organic molecules was given. Shorter wavelength excitation of biomolecules in the blue-green regions of the visible spectrum using a conventional dispersive spectrometer was more rapid but very dependent upon the type of chemical compound being studied; most relevant biomolecules fluoresced at these wavelengths but carotenoids exhibited a resonance effect which resulted in an improved detection capability. Minerals and geological materials, in contrast, were best studied at these visible wavelengths. In general, the best compromise system for the excitation of the Raman spectra of both geological and biological materials was provided using a 785 nm laser coupled with a dispersive spectrometer, especially for accessing the 1800–200 cm⁻¹ wavenumber shift region where much of the definitive analytical information resides. This work will have conclusions relevant to the use of miniaturised Raman spectrometers for the detection of biomolecules in extraterrestrial planetary exploration.     

Assessing the generality of global leaf trait relationships

Global-scale quantification of relationships between plant traits gives insight into the evolution of the world's vegetation, and is crucial for parameterizing vegetation-climate models. A database was compiled, comprising data for hundreds to thousands of species for the core 'leaf economics' traits leaf lifespan, leaf mass per area, photosynthetic capacity, dark respiration, and leaf nitrogen and phosphorus concentrations, as well as leaf potassium, photosynthetic N-use efficiency (PNUE), and leaf N : P ratio. While mean trait values differed between plant functional types, the range found within groups was often larger than differences among them. Future vegetation-climate models could incorporate this knowledge. The core leaf traits were intercorrelated, both globally and within plant functional types, forming a 'leaf economics spectrum'. While these relationships are very general, they are not universal, as significant heterogeneity exists between relationships fitted to individual sites. Much, but not all, heterogeneity can be explained by variation in sample size alone. PNUE can also be considered as part of this trait spectrum, whereas leaf K and N : P ratios are only loosely related.     

Maintenance of sex-linked deleterious alleles by selfing and group selection in metapopulations of the phytopathogenic fungus Microbotryum violaceum

Microbotryum violaceum is a fungus that causes the sterilizing anther smut disease in many Caryophyllaceae. Its diploid teliospores are heterozygous at the mating-type locus, normally producing equal proportions of haploid sporidia of the two mating types. However, natural populations contain high frequencies of individuals producing sporidia of only one mating type. This mating-type ratio bias is caused by the presence of deleterious alleles at haploid phase ("haplo-lethals") linked to the mating-type locus. These haplo-lethals can be transmitted if there is conjugation among the products of meiosis (intratetrad selfing). Haplo-lethals still suffer from selective disadvantages, through reducing the infection probability of strains that carry them, and thus cannot persist in a panmictic population. We develop a realistic model of a metapopulation of M. violaceum on its host Silene latifolia. Simulations show that if intratetrad selfing rate is high, haplo-lethals can be maintained under a metapopulation structure because of founder effects and selection at the population level. Populations founded only by strains carrying haplo-lethals experience a lower extinction rate precisely because of their lower infection ability; they spread more slowly and sterilize fewer plants, thereby allowing their host population to grow more rapidly and therefore to be less prone to extinction.