Summary
The overuse of veterinary antibiotics in animal production and the subsequent land applications of manures contribute to the elevated antibiotic resistance in the soil environment. To ...minimize the risk of antibiotic resistance, it is important to understand the fate of antibiotics and the spread of antibiotic resistance genes (ARGs) from animal production systems to soil. In this paper, we review recent studies on veterinary antibiotic use, the concentrations of antibiotics and the abundance and diversity of AGRs in animal manures and in soil that receives manures or manure composts. The mechanisms of ARG dissemination in the environment are also discussed. Although we focus on China where around 3 billion tons of animal manures are produced and more than 84 000 tons of antibiotics are consumed annually in animal production industries, the problem is worldwide. Approximately 58% of the veterinary antibiotics consumed are excreted into the environment, more than half of which end up in the soil. The abundance of ARGs in manures can reach up to 10−1 of the 16S rRNA genes. Applications of manures or manure composts can enrich soil ARGs in at least three ways: (i) by the direct introduction of manure‐derived ARGs, (ii) by elevating the intrinsic soil ARGs and (iii) by imposing a selection of ARGs with the antibiotics in the manures. We also discuss the need for more stringent regulations on the use of veterinary antibiotics and future research directions on the mechanisms of antibiotic resistance and resistance management.
Highlights
Soil is a natural reservoir of antibiotics and antibiotic resistance genes (ARGs).
Manure applications introduce antibiotics and enrich soil ARGs through different mechanisms.
Horizontal gene transfer plays an important role in the spread of ARGs from manures.
More stringent regulations are needed to reduce the spread of ARG from animal sources.
Our understanding of when and how humans adapted to living on the Tibetan Plateau at altitudes above 2000 to 3000 meters has been constrained by a paucity of archaeological data. Here we report data ...sets from the northeastern Tibetan Plateau indicating that the first villages were established only by 5200 calendar years before the present (cal yr B.P.). Using these data, we tested the hypothesis that a novel agropastoral economy facilitated year-round living at higher altitudes since 3600 cal yr B.P. This successful subsistence strategy facilitated the adaptation of farmers-herders to the challenges of global temperature decline during the late Holocene.
An overview of Sun–Sky Radiometer Observation Network (SONET) measurements in China is presented. Based on observations at 16 distributed SONET sites in China, atmospheric aerosol parameters are ...acquired via standardization processes of operational measurement, maintenance, calibration, inversion, and quality control implemented since 2010. A climatology study is performed focusing on total columnar atmospheric aerosol characteristics, including optical (aerosol optical depth, ÅngstrÖm exponent, fine-mode fraction, single-scattering albedo), physical (volume particle size distribution), chemical composition (black carbon; brown carbon; fine-mode scattering component, coarse-mode component; and aerosol water), and radiative properties (aerosol radiative forcing and efficiency). Data analyses show that aerosol optical depth is low in the west but high in the east of China. Aerosol composition also shows significant spatial and temporal variations, leading to noticeable diversities in optical and physical property patterns. In west and north China, aerosols are generally affected by dust particles, while monsoon climate and human activities impose remarkable influences on aerosols in east and south China. Aerosols in China exhibit strong light-scattering capability and result in significant radiative cooling effects.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract Some types of peripheral neuropathic pain are associated with damage to myelin rather than to axons of primary sensory neurons. It is extremely important to develop selective demyelination ...animal models for understanding neuropathic pain caused by demyelination. We induced a rapid-onset and reversible demyelination of peripheral A-fibers and neuropathic pain behaviors in adult rats by a single injection of cobra venom into the sciatic nerve. The relation between A-fiber demyelination and the abnormal pain behaviors was investigated using this model. Microfilament recordings revealed that cobra venom selectively blocked A-fibers, but not C-fibers. Selective blockade of A-fibers may result from A-fiber demyelination at the site of venom injection as demonstrated by microscope examination. The axons of the demyelinated A-fibers appeared to be otherwise normal. Neuropathic pain behaviors appeared almost immediately after venom injection and lasted about 3 weeks. Electrophysiological studies indicated that venom injection induced loss of conduction in A-fibers, increased sensitivity of C-polymodal nociceptors to innocuous stimuli, and triggered spontaneous activity from both peripheral and central terminals of C-fiber nociceptors. Neurogenic inflammatory responses were also observed in the affected skin via Evan's Blue extravasation experiments. Both antidromic C-fiber spontaneous activity and neurogenic inflammation were substantially decreased by continuous A-fiber threshold electric stimuli applied proximally to the venom injection site. The data suggest that normal activity of peripheral A-fibers may produce inhibitory modulation of C-fiber polymodal nociceptors. Removal of inhibition to C-fiber polymodal nociceptors following demyelination of A-fibers may result in pain and neurogenic inflammation in the affected receptive field.
Aggregation‐induced emission (AIE) has been harnessed in many systems through the principle of restriction of intramolecular rotations (RIR) based on mechanistic understanding from archetypal AIE ...molecules such as tetraphenylethene (TPE). However, as the family of AIE‐active molecules grows, the RIR model cannot fully explain some AIE phenomena. Here, we report a broadening of the AIE mechanism through analysis of 10,10′,11,11′‐tetrahydro‐5,5′‐bidibenzoa,d7annulenylidene (THBDBA), and 5,5′‐bidibenzoa,d7annulenylidene (BDBA). Analyses of the computational QM/MM model reveal that the novel mechanism behind the AIE of THBDBA and BDBA is the restriction of intramolecular vibration (RIV). A more generalized mechanistic understanding of AIE results by combining RIR and RIV into the principle of restriction of intramolecular motions (RIM).
Luminescence turn‐on: Through theoretical calculations to explain empirical observation, it is now possible to more fully explain the phenomenon of aggregation‐induced emission. By comparing tetraphenylethene and its structurally similar analogues, deeper insight has been gained into this photophysical phenomenon in which luminescence can be turned on in the aggregated or solid state.
Summary
Our network meta-analysis analyzed the effects of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) on fracture risk. By combining data from randomized controlled trials, we found that ...GLP-1 RAs were associated with a decreased bone fracture risk, and exenatide is the best option agent with regard to the risk of fracture. This study is registered with PROSPERO (CRD42018094433).
Introduction
Data on the effects of GLP-1 RAs on fracture risk are conflicted. This study aimed to analyze the available evidence on the effects of GLP-1 RAs on fracture risk in type 2 diabetes mellitus patients.
Methods
Electronic databases were searched for relevant published articles, and unpublished studies presented at
ClinicalTrials.gov
were searched for relevant clinical data. All analyses were performed with STATA 12.0 and R software (Version 3.4.4). We estimated the risk ratio (RR) and 95% confidence interval (CI) by combining RRs for fracture effects of included trials.
Results
There were 54 eligible random control trials (RCTs) with 49,602 participants, including 28,353 patients treated with GLP-1 RAs. Relative to placebo, exenatide (RR, 0.17; 95% CI 0.03–0.67) was associated with lowest risk of fracture among other GLP-1 RAs. Exenatide had the highest probability to be the safest option with regard to the risk of fracture (0.07 ‰), followed by dulaglutide (1.04%), liraglutide (1.39%), albiglutide (5.61%), lixisenatide (8.07%), and semaglutide (18.72%). A statistically significant inconsistency was observed in some comparisons.
Conclusion
The Bayesian network meta-analysis suggests that GLP-1 RAs were associated with a decreased bone fracture risk compared to users of placebo or other anti-hyperglycemic drugs in type 2 diabetes mellitus patients, and exenatide is the best option agent with regard to the risk of fracture.
Abstract
The Comprehensive Research Facility for Fusion Technology (CRAFT) is a large scientific
facility that is preferentially deployed for the construction of major national science and
technology ...infrastructures. A negative beam source based neutral beam injector (NNBI) with beam
energy of 200–400 keV, beam power of 2 MW and beam duration of 100 s is one of the devices. A
giant radio frequency (RF) based negative beam source was designed for the CRAFT NNBI system. In
order to understand the physics and pre-study the engineering problems for RF negative beams
source, several beam sources with different scales will be designed and tested. According to the
R&D schedule, a negative beam source with a single driver was designed, developed and tested
first. The single driver beam source is a quarter of the size of the full size negative beam
source. It contains an RF driver, an expansion chamber and a negative ion accelerator with three
electrodes, which are a plasma grid (PG), extraction grid (EG) and ground grid (GG). To enhance
the negative ion production, Cesium is injected into the plasma chamber and a magnetic filter
filed is produced by current flow through the PG to decrease the electron temperature. The
negative beam source was tested on the test facility after assembly, including RF plasma
generation, negative ion production, extraction and acceleration. The characteristic of plasma
discharge, beam extraction and acceleration was studied without and with Cs injection. The long
pulse of 105 seconds negative ion beam was achieved successfully. The extracted negative ion
current is 4 A and the ratio of electron and negative ion is around 0.8. It lays a good foundation
for the R&D of negative ion source with a multi-driver for the CRAFT NNBI system. The details of
the design and experimental results of beam source was shown in this paper.
Ferromagnetism is observed at ferroelastic domain walls in strontium titanate and its heterostructures with other oxides. Applying strain can reverse the magnetism. This suggests the possibility of ...device engineering using domain walls.
Background
Glycolysis is a critical pathway in cellular glucose metabolism that provides energy and participates in immune responses. However, whether glycolysis is involved in NOD‐like receptor ...family protein 3 (NLRP3) inflammasome activation and phagocytosis of macrophages in response to Treponema pallidum infection remains unclear.
Objectives
To investigate the role of glycolysis in activating the NLRP3 inflammasome for regulating phagocytosis in macrophages in response to T. pallidum protein Tp47 and its associated mechanisms.
Methods
Interactions between activation of the NLRP3 inflammasome and phagocytosis and the role of glycolysis in Tp47‐treated macrophages were investigated through experiments on peritoneal macrophages and human monocytic cell line‐derived macrophages.
Results
Activation of phagocytosis and NLRP3 inflammasome were observed in Tp47‐treated macrophages. Treatment with NLRP3 inhibitor MCC950 or si‐NLRP3 attenuated Tp47‐induced phagocytosis. Glycolysis and glycolytic capacity were enhanced by Tp47 stimulation in macrophages, and a change in the levels of glycolytic metabolites (phosphoenolpyruvate, citrate and lactate) was induced by Tp47 in macrophages. Inhibition of glycolysis with 2‐deoxy‐D‐glucose, a glycolysis inhibitor, decreased the activation of NLRP3. Expression of M2 isoform of pyruvate kinase (PKM2), an enzyme catalysing a rate‐limiting reaction in the glycolytic pathway, was upregulated in Tp47‐stimulated macrophages. Inhibition of PKM2 with shikonin or si‐PKM2 decreased glycolysis and NLRP3 activation.
Conclusion
Tp47 promotes phagocytosis in macrophages by activating the NLRP3 inflammasome, which is induced by the enhancement of PKM2‐dependent glycolysis.
Plasma DNA fragmentomics is an emerging area of research covering plasma DNA sizes, end points, and nucleosome footprints. In the present study, we found a significant increase in the diversity of ...plasma DNA end motifs in patients with hepatocellular carcinoma (HCC). Compared with patients without HCC, patients with HCC showed a preferential pattern of 4-mer end motifs. In particular, the abundance of plasma DNA motif CCCA was much lower in patients with HCC than in subjects without HCC. The aberrant end motifs were also observed in patients with other cancer types, including colorectal cancer, lung cancer, nasopharyngeal carcinoma, and head and neck squamous cell carcinoma. We further observed that the profile of plasma DNA end motifs originating from the same organ, such as the liver, placenta, and hematopoietic cells, generally clustered together. The profile of end motifs may therefore serve as a class of biomarkers for liquid biopsy in oncology, noninvasive prenatal testing, and transplantation monitoring. SIGNIFICANCE: Plasma DNA molecules originating from the liver, HCC and other cancers, placenta, and hematopoietic cells each harbor a set of characteristic plasma DNA end motifs. Such markers carry tissue-of-origin information and represent a new class of biomarkers in the nascent field of fragmentomics.
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