Mid-Holocene environmental and human dynamics in northeastern China reconstructed from pollen and archaeological data

A pollen record from the Taishizhuang site (40°21.5′N, 115°49.5′E) located in the transitional forest-steppe zone near the present-day limit of the summer monsoon is used to reconstruct vegetation and climate. Quantitative biome reconstruction suggests that between ca. 5700 and 4400 cal. years B.P. temperate deciduous forest dominated the vegetation cover around the Taishizhuang site. After that time the landscape became more open and the scores of the steppe biome were always higher than those of the temperate deciduous forest except for two oscillations dated to ca. 4000 cal. years B.P. and ca. 3500 cal. years B.P. However, ca. 3400-2100 cal. years B.P. the common vegetation became steppe and the landscape was more open in comparison with the previous time interval. The results of the pollen-based precipitation reconstruction suggest that annual precipitation was ca. 550-750 mm (ca. 100-300 mm higher than present) during the mid-Holocene ‘forest phase’, and ca. 450-650 mm during the following ‘forest-steppe phase’. From ca. 3400 cal. years B.P. during the ‘steppe phase’ annual precipitation was similar to modern values (ca. 300-500 mm). Archaeological records from 100 sites prove the habitation of northeastern China during the prehistoric and early historic periods from ca. 8200 cal. years B.P., but do not provide evidence of the use of wood resources intensive enough to influence the regional vegetation development and to leave traces in the pollen assemblages. Both archaeological and palaeoenvironmental data support the conclusion that changes in pollen composition in northeastern China between 5700 and 2100 cal. years B.P. reflect natural variations in precipitation and not major deforestation caused by humans.     

Radioecological investigation of the soil cover of eastern Urals State radioactive reserve and neighboring areas

The contamination levels and spatial distribution of 90Sr and 137Cs in the soil cover of the Eastern Ural State Radioactive Reserve and neighboring areas have been studied. Situated in the Chelyabinsk region, the Reserve embraces the frontal part of the Eastern Urals Radioactive Trace. This Trace emerged in 1957 as a result of the nuclear accident at the Production Association "Mayak". In the studied areas, the content of radionuclides in soils decreases exponentially as the distance from the source of contamination increases. 90Sr received by the soil cover as a result of the accident in 1957 has remained the main contaminant of the Reserve central part (97% of the total contamination). Its contribution throughout western neighboring areas reduces up to 67%, which decreases the effect of 90Sr on the environment. Within eastern neighboring areas, soil is mainly contaminated by 137Cs received as a result of the wind disseminated dried sediments from the shores of Lake Karachay (1967) that was used for dumping high-level radioactive waste. Also observed was enrichment of forest litters with this radionuclide due to current atmospheric fallout.     

The miRNA aberrant expression dependence on DNA methylation in HeLa cells treated with mitomycin C

The dependence of expression of miRNAs and their precursors (pre-miRNAs) on the DNA methylation level in HeLa cells 8 days after mitomycin C treatment was studied. A massive parallel DNA sequencing method was applied to analyze miRNA expression. 5-Azacytidine (DNA methylation inhibitor) was added to the medium 6 days after mutagenic agent exposure. The results indicated that the change in expression for some mature miRNAs (39 of 61) was accompanied by the change in the expression of their pre-miRNAs, while there were no significant changes in the expression of pre-miRNA for other mature miRNAs (22 of 61). The aberrant expression was maintained by 8 of 61 mature miRNAs and 6 of 55 pre-miRNAs in the induced HeLa cells after 5-azacytidine treatment. In addition, the expression of more than 90% of miRNAs, which indicated a significant change in expression after mitomycin C treatment, does not depend or depends slightly on the DNA methylation level in HeLa cells without mitomycin C treatment. The results suggest that mitomycin C induces aberrant DNA methylation which affects maintenance of changes in the miRNA expression in cell generations after mutagen treatment.     

Phylogeography of the temperate marine bivalve Cerastoderma edule (Linnaeus, 1758) (Bivalvia: Cardiidae) in the Subarctic: Unique diversity and strong population structuring at different spatial scales

Using mitochondrial COI sequencing, we explored the genetic diversity and population structuring of the common cockle Cerastoderma edule (Linnaeus, 1758) in the Norwegian and Barents Seas. Phylogeographic diversity and hence the evolutionary history of C. edule on the Scandinavian and Russian coastlines were found to be richer than expected for populations of temperate species in postglacially colonized seas. A major phylogeographic break at Lofoten Islands separated a group of subarctic populations dominated by a distinct star‐shaped clade of haplotypes from those to the south, extending to the North Sea and having highest gene diversities (h). At the northeastern edge of the range of C. edule, the Russian Murman coast, populations show a mosaic structure with considerable admixture of haplotypes from the south and high local‐scale variation in haplotype diversity (ranging between 0 and 0.8). To explain this mosaic we refer to the core‐satellite metapopulation model, with Norwegian populations as core, and Murman populations as satellites. Our results contradict the conventional biogeographic paradigm implying lack of metapopulation structuring in marine broadcast spawning invertebrates. Hypotheses considered to explain the origin of the unique variation in cockles from Northern Norway involve an early postglacial colonization and establishment of these populations (10–12 ka ago), a persistent oceanographic break at Lofoten, and a mitochondrial selective sweep associated with the postglacial recolonization of the subarctic seas by the boreal C. edule.     

Use of inert gas jets to measure the forces required for mechanical gene transfection

Background

Abnormal blood glucose (BG) concentrations have been associated with increased morbidity and mortality in both critically ill adults and infants. Furthermore, hypoglycaemia and glycaemic variability have both been independently linked to mortality in these patients. Continuous Glucose Monitoring (CGM) devices have the potential to improve detection and diagnosis of these glycaemic abnormalities. However, sensor noise is a trade-off of the high measurement rate and must be managed effectively if CGMs are going to be used to monitor, diagnose and potentially help treat glycaemic abnormalities.

Aim

To develop a tool that will aid clinicians in identifying unusual CGM behaviour and highlight CGM data that potentially need to be interpreted with care.

Methods

CGM data and BG measurements from 50 infants at risk of hypoglycaemia were used. Unusual CGM measurements were classified using a stochastic model based on the kernel density method and historical CGM measurements from the cohort. CGM traces were colour coded with very unusual measurements coloured red, highlighting areas to be interpreted with care. A 5-fold validation of the model was Monte Carlo simulated 25 times to ensure an adequate model fit.

Results

The stochastic model was generated using ~67,000 CGM measurements, spread across the glycaemic range ~2-10?mmol/L. A 5-fold validation showed a good model fit: the model 80% confidence interval (CI) captured 83% of clinical CGM data, the model 90% CI captured 91% of clinical CGM data, and the model 99% CI captured 99% of clinical CGM data. Three patient examples show the stochastic classification method in use with 1) A stable, low variability patient which shows no unusual CGM measurements, 2) A patient with a very sudden, short hypoglycaemic event (classified as unusual), and, 3) A patient with very high, potentially un-physiological, glycaemic variability after day 3 of monitoring (classified as very unusual).

Conclusions

This study has produced a stochastic model and classification method capable of highlighting unusual CGM behaviour. This method has the potential to classify important glycaemic events (e.g. hypoglycaemia) as true clinical events or sensor noise, and to help identify possible sensor degradation. Colour coded CGM traces convey the information quickly and efficiently, while remaining computationally light enough to be used retrospectively or in real-time.     

The study of structure-antiarrhythmic activity relationship of N-phenylacetamide derivatives and aromatic carbonic acid amides

Using the SARD-21 (Structure Activity Relationship & Design) computer system, structural features of high- and low-effective antiarrhythmic agents have been recognized and the influence of these features on the antiarrhythmic properties has been evaluated. This information has been used for generation of the model to predict antiarrhythmic effectiveness of pharmaceutical preparations at the recognition level of 82% by means of two different approaches. The recognized structural parameters may be successfully used to design new highly effective antiarrhythmic drugs, and also to modify structures of the already-existing anti-arrhythmic drugs in order to increase the effectiveness of their antiarrhythmic action.     

Non-selective cation channels, transient receptor potential channels and ischemic stroke

Several pathways to neural cell death are involved in ischemic stroke, and all require monovalent or divalent cation influx, implicating non-selective cation (NC) channels. NC channels are also likely to be involved in the dysfunction of vascular endothelial cells that leads to formation of edema following cerebral ischemia. Two newly described NC channels have emerged as potential participants in ischemic stroke, the acid sensing ion channel (ASIC), and the sulfonylurea receptor-1 (SUR1)-regulated NC(Ca-ATP) channel. Non-specific blockers of NC channels, including pinokalant (LOE 908 MS) and rimonabant (SR141716A), have beneficial effects in rodent models of ischemic stroke. Evidence is accumulating that NC channels formed by members of the transient receptor potential (TRP) family are also up-regulated in ischemic stroke and may play a direct role in calcium-mediated neuronal death. The nascent field of NC channels, including TRP channels, in ischemic stroke is poised to provide novel mechanistic insights and therapeutic strategies for this often devastating human condition.     

MicroRNA-Dependent Regulation of <Emphasis Type="Italic">IGF1R</Emphasis> Gene Expression in Hormone-Sensitive and Hormone-Resistant Prostate Cancer Cells

Using multiple parallel sequencing on Illumina platform, we identified eight microRNAs that showed significant opposite changes of gene expression in cells of the hormone-sensitive LNCaP prostate cancer cell line and in cells of the hormone-resistant DU-145 cell line, in comparison to the microRNA expression in the normal prostate tissue cells. We found that the insulin-like growth factor 1 receptor (IGF1R) gene is a target of five microRNAs whose expression is increased in LNCaP cells and reduced in DU-145 cells.