Structural, stereochemical, and bioactive studies of cembranoids from Chinese soft coral Sarcophyton trocheliophorum

LBK

Solar microwave millisecond spike at 2.84 GHz

Using the high time resolution of 1 ms, the data of solar microwave millisecond spike (MMS) event was recorded more than two hundred times at the frequency of 2.84 GHz at Beijing (Peking) Observatory since May 1981. A preliminary analysis was made. It can be seen from the data that the MMS-events have a variety of the fast activities such as the dispersed and isolated spikes, the clusters of the crowded spikes, the weak spikes superimposed on the noise background, and the phenomena of absorption. The marked differences from that observed with lower time resolution are presented. Using the data, a valuable statistical analysis was made. There are close correlations between MMS-events and hard X-ray bursts, and fast drifting bursts. The MMS events are highly dependent on the type of active regions and the magnetic field configuration. It seems to be crucial to find out the accurate positions on the active region where the MMS-events happen and to make co-operative observations at different bands during the special period when specific active regions appear on the solar disk

Metabolically Specific In Situ Fluorescent Visualization of Bacterial Infection on Wound Tissues

The ability to effectively detect bacterial infection in human tissues is important for the timely treatment of the infection. However, traditional techniques fail to visualize bacterial species adhered to host cells in situ in a target-specific manner. Dihydropteroate synthase (DHPS) exclusively exists in bacterial species and metabolically converts p-aminobenzoic acid (PABA) to folic acid (FA). By targeting this bacterium-specific metabolism, we have developed a fluorescent imaging probe, PABA-DCM, based on the conjugation of PABA with a long-wavelength fluorophore, dicyanomethylene 4H-pyran (DCM). We confirmed that the probe can be used in the synthetic pathway of a broad spectrum of Gram-positive and negative bacteria, resulting in a significantly extended retention time in bacterial over mammalian cells. We validated that DHPS catalytically introduces a dihydropteridine group to the amino end of the PABA motif of PABA-DCM, and the resulting adduct leads to an increase in the FA levels of bacteria. We also constructed a hydrogel dressing containing PABA-DCM and graphene oxide (GO), termed PABA-DCM@GO, that achieves target-specific fluorescence visualization of bacterial infection on the wounded tissues of mice. Our research paves the way for the development of fluorescent imaging agents that target species-conserved metabolic pathways of microorganisms for the in situ monitoring of infections in human tissues. </p

Genetical genomics: spotlight on QTL hotspots

No abstract available

The role of dipole interactions in hyperthermia heating colloidal clusters of densely-packed superparamagnetic nanoparticles

This work aims to investigate the influence of inter-particle dipole interactions on hyperthermia heating colloidal clusters of densely-packed Fe3O4 nanoparticles at low field intensity. Emulsion droplet solvent evaporation method was used to assemble oleic acid modified Fe3O4 particles into compact clusters which were stabilized by surfactant in water. Both experimental and simulation works were conducted to study their heating performance at different cluster’s sizes. The dipole interactions improve the heating only when the clusters are small enough to bring an enhancement in clusters’ shape anisotropy. The shape anisotropy is reduced at greater clusters’ sizes, since the shapes of the clusters become more and more spherical. Consequently, the dipole interactions change to impair the heating efficiency at larger sizes. When the clusters are totally isotropic in shape, the heating efficiency is lower than that of non-interacting particles despite the cluster’s size, although the efficiency increases by a little bit at a particular size most likely due to the dipole couplings. In these situations, one has to use particles with higher magnetic anisotropy and/or saturation magnetization to improve the heating

Genes but Not Genomes Reveal Bacterial Domestication of Lactococcus Lactis

BACKGROUND: The population structure and diversity of Lactococcus lactis subsp. lactis, a major industrial bacterium involved in milk fermentation, was determined at both gene and genome level. Seventy-six lactococcal isolates of various origins were studied by different genotyping methods and thirty-six strains displaying unique macrorestriction fingerprints were analyzed by a new multilocus sequence typing (MLST) scheme. This gene-based analysis was compared to genomic characteristics determined by pulsed-field gel electrophoresis (PFGE). METHODOLOGY/PRINCIPAL FINDINGS: The MLST analysis revealed that L. lactis subsp. lactis is essentially clonal with infrequent intra- and intergenic recombination; also, despite its taxonomical classification as a subspecies, it displays a genetic diversity as substantial as that within several other bacterial species. Genome-based analysis revealed a genome size variability of 20%, a value typical of bacteria inhabiting different ecological niches, and that suggests a large pan-genome for this subspecies. However, the genomic characteristics (macrorestriction pattern, genome or chromosome size, plasmid content) did not correlate to the MLST-based phylogeny, with strains from the same sequence type (ST) differing by up to 230 kb in genome size. CONCLUSION/SIGNIFICANCE: The gene-based phylogeny was not fully consistent with the traditional classification into dairy and non-dairy strains but supported a new classification based on ecological separation between "environmental" strains, the main contributors to the genetic diversity within the subspecies, and "domesticated" strains, subject to recent genetic bottlenecks. Comparison between gene- and genome-based analyses revealed little relationship between core and dispensable genome phylogenies, indicating that clonal diversification and phenotypic variability of the "domesticated" strains essentially arose through substantial genomic flux within the dispensable genome

Dissecting the physiology and pathophysiology of glucagon-like peptide-1

Copyright © 2018 Paternoster and Falasca. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. An aging world population exposed to a sedentary life style is currently plagued by chronic metabolic diseases, such as type-2 diabetes, that are spreading worldwide at an unprecedented rate. One of the most promising pharmacological approaches for the management of type 2 diabetes takes advantage of the peptide hormone glucagon-like peptide-1 (GLP-1) under the form of protease resistant mimetics, and DPP-IV inhibitors. Despite the improved quality of life, long-term treatments with these new classes of drugs are riddled with serious and life-threatening side-effects, with no overall cure of the disease. New evidence is shedding more light over the complex physiology of GLP-1 in health and metabolic diseases. Herein, we discuss the most recent advancements in the biology of gut receptors known to induce the secretion of GLP-1, to bridge the multiple gaps into our understanding of its physiology and pathology

Environmental effects of ozone depletion, UV radiation and interactions with climate change : UNEP Environmental Effects Assessment Panel, update 2017

Peer reviewe

The 16th Data Release of the Sloan Digital Sky Surveys: First Release from the APOGEE-2 Southern Survey and Full Release of eBOSS Spectra

This paper documents the 16th data release (DR16) from the Sloan Digital Sky Surveys (SDSS), the fourth and penultimate from the fourth phase (SDSS-IV). This is the first release of data from the Southern Hemisphere survey of the Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2); new data from APOGEE-2 North are also included. DR16 is also notable as the final data release for the main cosmological program of the Extended Baryon Oscillation Spectroscopic Survey (eBOSS), and all raw and reduced spectra from that project are released here. DR16 also includes all the data from the Time Domain Spectroscopic Survey and new data from the SPectroscopic IDentification of ERosita Survey programs, both of which were co-observed on eBOSS plates. DR16 has no new data from the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey (or the MaNGA Stellar Library "MaStar"). We also preview future SDSS-V operations (due to start in 2020), and summarize plans for the final SDSS-IV data release (DR17)