Glomus mosseae,endomycorrhizal with Liquidambar styraciflua L. seedlings retards NO3, NO2 and NH4 nitrogen loss from a temperate forest soil

Summary The influence of a mycorrhizal fungus on downward movement of NH₄, NO₂, and NO₃ nitrogen in forest soil was determined by establishing combinations of soil, fungus and seedlings in plastic pipes and monitoring the nitrogen content of water percolating to two depths. Compared with controls of soil alone and of soil + seedling alone, treatments containing the mycorrhizae showed a significant reduction of NH₄-N loss from 5 and 25 cm depths and significant reduction of NO₃-N loss from the 5 cm depth. No significant effect was observed on nitrite loss. re]19750603     

Biological clocks as age estimation markers in animals: a systematic review and meta-analysis

Various biological attributes associated with individual fitness in animals change predictably over the lifespan of an organism. Therefore, the study of animal ecology and the work of conservationists frequently relies upon the ability to assign animals to functionally relevant age classes to model population fitness. Several approaches have been applied to determining individual age and, while these methods have proved useful, they are not without limitations and often lack standardisation or are only applicable to specific species. For these reasons, scientists have explored the potential use of biological clocks towards creating a universal age-determination method. Two biological clocks, tooth layer annulation and otolith layering have found universal appeal. Both methods are highly invasive and most appropriate for post-mortem age-at-death estimation. More recently, attributes of cellular ageing previously explored in humans have been adapted to studying ageing in animals for the use of less-invasive molecular methods for determining age. Here, we review two such methods, assessment of methylation and telomere length, describing (i) what they are, (ii) how they change with age, and providing (iii) a summary and meta-analysis of studies that have explored their utility in animal age determination. We found that both attributes have been studied across multiple vertebrate classes, however, telomere studies were used before methylation studies and telomere length has been modelled in nearly twice as many studies. Telomere length studies included in the review often related changes to stress responses and illustrated that telomere length is sensitive to environmental and social stressors and, in the absence of repair mechanisms such as telomerase or alternative lengthening modes, lacks the ability to recover. Methylation studies, however, while also detecting sensitivity to stressors and toxins, illustrated the ability to recover from such stresses after a period of accelerated ageing, likely due to constitutive expression or reactivation of repair enzymes such as DNA methyl transferases. We also found that both studied attributes have parentally heritable features, but the mode of inheritance differs among taxa and may relate to heterogamy. Our meta-analysis included more than 40 species in common for methylation and telomere length, although both analyses included at least 60 age-estimation models. We found that methylation outperforms telomere length in terms of predictive power evidenced from effect sizes (more than double that observed for telomeres) and smaller prediction intervals. Both methods produced age correlation models using similar sample sizes and were able to classify individuals into young, middle, or old age classes with high accuracy. Our review and meta-analysis illustrate that both methods are well suited to studying age in animals and do not suffer significantly from variation due to differences in the lifespan of the species, genome size, karyotype, or tissue type but rather that quantitative method, patterns of inheritance, and environmental factors should be the main considerations. Thus, provided that complex factors affecting the measured trait can be accounted for, both methylation and telomere length are promising targets to develop as biomarkers for age determination in animals.     

Statin use and peripheral sensory perception: A pilot study

Objectives. Peripheral sensory neuropathy is a neurological deficit resulting in decreased detection of sensation through the peripheral nervous system. Peripheral sensory neuropathy is commonly diagnosed with the use of a monofilament and either a tuning fork or neurothesiometer. Statins are a widely used medication and there has been some debate of association with their use and peripheral sensory neuropathy. This pilot study aimed to test the sensory perception of participants with long-term statin use and compare these results to their peers who were not taking statins.

Methods. Thirty participants were recruited and equally divided into a statin and non-statin group. Healthy participants were screened by their medical and medication history, Australian Type 2 Diabetes Risk assessment, and random blood glucose level. An assessor who was blinded to the participant group conducted sensory assessments using a 10?g monofilament and neurothesiometer.

Results. There was no difference in monofilament testing results between the groups. The statin group was less sensate at the styloid process (p?=?0.031) and medial malleolus (p?=?0.003) than the control group. Results at the hallux were not statistically significant (p?=?0.183).

Conclusion. This result is suggestive of a potential association between long-term statin use and a decrease in peripheral sensory perception. This may be because of peripheral sensory neuropathy. Limitations such as consideration of participant height, participant numbers, and inability to analyze results against statin groups are reported. As statins are a life-saving medication, careful consideration should be applied to these results and further research be conducted to determine if these results are applicable to larger populations.     

Flax processing in the Neolithic and Bronze Age pile-dwelling settlements of eastern Switzerland

Numerous artefacts from the area of textile production as well as finished products, fabrics and netting, dating from the period between 3900 and 800 b.c. have survived in the archaeological layers of late Neolithic and Bronze Age wetland settlements in eastern Switzerland. Archaeological investigations, experiments in textile technology and comparisons with Egyptian wall paintings, as well as analyses under the scanning electron microscope, allow us to almost completely reconstruct Neolithic textile production in prehistoric pile dwellings.     

Examination of tetrahydrobiopterin pathway genes in autism

Autism is a complex disorder with a high degree of heritability and significant phenotypic and genotypic heterogeneity. Although candidate gene studies and genome-wide screens have failed to identify major causal loci associated with autism, numerous studies have proposed association with several variations in genes in the dopaminergic and serotonergic pathways. Because tetrahydrobiopterin (BH4) is the essential cofactor in the synthesis of these two neurotransmitters, we genotyped 25 SNPs in nine genes of the BH4 pathway in a total of 403 families. Significant nominal association was detected in the gene for 6-pyruvoyl-tetrahydropterin synthase, PTS (chromosome 11), with P = 0.009; this result was not restricted to an affected male-only subset. Multilocus interaction was detected in the BH4 pathway alone, but not across the serotonin, dopamine and BH4 pathways.