NAD tagSeq reveals that NAD+-capped RNAs are mostly produced from a large number of protein-coding genes in Arabidopsis.

The 5' end of a eukaryotic mRNA transcript generally has a 7-methylguanosine (m7G) cap that protects mRNA from degradation and mediates almost all other aspects of gene expression. Some RNAs in Escherichia coli, yeast, and mammals were recently found to contain an NAD+ cap. Here, we report the development of the method NAD tagSeq for transcriptome-wide identification and quantification of NAD+-capped RNAs (NAD-RNAs). The method uses an enzymatic reaction and then a click chemistry reaction to label NAD-RNAs with a synthetic RNA tag. The tagged RNA molecules can be enriched and directly sequenced using the Oxford Nanopore sequencing technology. NAD tagSeq can allow more accurate identification and quantification of NAD-RNAs, as well as reveal the sequences of whole NAD-RNA transcripts using single-molecule RNA sequencing. Using NAD tagSeq, we found that NAD-RNAs in Arabidopsis were produced by at least several thousand genes, most of which are protein-coding genes, with the majority of these transcripts coming from <200 genes. For some Arabidopsis genes, over 5% of their transcripts were NAD capped. Gene ontology terms overrepresented in the 2,000 genes that produced the highest numbers of NAD-RNAs are related to photosynthesis, protein synthesis, and responses to cytokinin and stresses. The NAD-RNAs in Arabidopsis generally have the same overall sequence structures as the canonical m7G-capped mRNAs, although most of them appear to have a shorter 5' untranslated region (5' UTR). The identification and quantification of NAD-RNAs and revelation of their sequence features can provide essential steps toward understanding the functions of NAD-RNAs

Electrospun chitosan-graft-poly (ɛ-caprolactone)/poly (ɛ-caprolactone) nanofibrous scaffolds for retinal tissue engineering

A promising therapy for retinal diseases is to employ biodegradable scaffolds to deliver retinal progenitor cells (RPCs) for repairing damaged or diseased retinal tissue. In the present study, cationic chitosan-graft-poly(ɛ-caprolactone)/polycaprolactone (CS-PCL/PCL) hybrid scaffolds were successfully prepared by electrospinning. Characterization of the obtained nanofibrous scaffolds indicated that zeta-potential, fiber diameter, and the content of amino groups on their surface were closely correlated with the amount of CS-PCL in CS-PCL/PCL scaffolds. To assess the cell–scaffold interaction, mice RPCs (mRPCs) were cultured on the electrospun scaffolds for 7 days. In-vitro proliferation assays revealed that mRPCs proliferated faster on the CS-PCL/PCL (20/80) scaffolds than the other electrospun scaffolds. Scanning electron microscopy and the real-time quantitative polymerase chain reaction results showed that mRPCs grown on CS-PCL/PCL (20/80) scaffolds were more likely to differentiate towards retinal neurons than those on PCL scaffolds. Taken together, these results suggest that CS-PCL/PCL(20/80) scaffolds have potential application in retinal tissue engineering

High atmospheric carbon dioxide-dependent alleviation of salt stress is linked to RESPIRATORY BURST OXIDASE 1 (RBOH1)-dependent H2O2 production in tomato (Solanum lycopersicum)

Plants acclimate rapidly to stressful environmental conditions. Increasing atmospheric CO2 levels are predicted to influence tolerance to stresses such as soil salinity but the mechanisms are poorly understood. To resolve this issue, tomato (Solanum lycopersicum) plants were grown under ambient (380 μmol mol–1) or high (760 μmol mol–1) CO2 in the absence or presence of sodium chloride (100 mM). The higher atmospheric CO2 level induced the expression of RESPIRATORY BURST OXIDASE 1 (SlRBOH1) and enhanced H2O2 accumulation in the vascular cells of roots, stems, leaf petioles, and the leaf apoplast. Plants grown with higher CO2 levels showed improved salt tolerance, together with decreased leaf transpiration rates and lower sodium concentrations in the xylem sap, vascular tissues, and leaves. Silencing SlRBOH1 abolished high CO2 -induced salt tolerance and increased leaf transpiration rates, as well as enhancing Na+ accumulation in the plants. The higher atmospheric CO2 level increased the abundance of a subset of transcripts involved in Na+ homeostasis in the controls but not in the SlRBOH1-silenced plants. It is concluded that high atmospheric CO2 concentrations increase salt stress tolerance in an apoplastic H2O2 dependent manner, by suppressing transpiration and hence Na+ delivery from the roots to the shoots, leading to decreased leaf Na+ accumulation

A Single Dose of Baicalin Has No Clinically Significant Effect on the Pharmacokinetics of Cyclosporine A in Healthy Chinese Volunteers

Despite its narrow therapeutic window and large interindividual variability, cyclosporine A (CsA) is the first-line therapy following organ transplantation. Metabolized mainly by CYP3A and being a substrate of P-glycoprotein (P-gp), CsA is susceptible to drug–drug interactions. Baicalin (BG) is a drug used for adjuvant therapy of hepatitis in traditional Chinese medicine. Since its aglycone baicalein (B) inhibits CYP3A and P-gP, co-administration might affect CsA pharmacokinetics. This study investigated the effect of BG on CsA pharmacokinetics. In a two-period study, 16 healthy volunteers received a single 200 mg oral CsA dose alone (reference period) or in combination with 500 mg BG (test period). Pharmacokinetic evaluation of CsA was carried out using non-compartmental analysis (NCA) and population pharmacokinetics (popPK). Treatments were compared using the standard bioequivalence method. Based on NCA, 90% CIs of AUC and Cmax test-to-reference ratios were within bioequivalence boundaries. In the popPK analysis, a two-compartment model (clearance/F 62.8 L/h, central and peripheral volume of distribution/F 254 L and 388 L) with transit compartments for absorption appropriately described CsA concentrations. No clinically relevant effect of 500 mg BG co-administration on CsA pharmacokinetics was identified and both treatments were well tolerated

A Combined Approach of High-Throughput Sequencing and Degradome Analysis Reveals Tissue Specific Expression of MicroRNAs and Their Targets in Cucumber

MicroRNAs (miRNAs) are endogenous small RNAs playing an important regulatory function in plant development and stress responses. Among them, some are evolutionally conserved in plant and others are only expressed in certain species, tissue or developmental stages. Cucumber is among the most important greenhouse species in the world, but only a limited number of miRNAs from cucumber have been identified and the experimental validation of the related miRNA targets is still lacking. In this study, two independent small RNA libraries from cucumber leaves and roots were constructed, respectively, and sequenced with the high-throughput Illumina Solexa system. Based on sequence similarity and hairpin structure prediction, a total of 29 known miRNA families and 2 novel miRNA families containing a total of 64 miRNA were identified. QRT-PCR analysis revealed that some of the cucumber miRNAs were preferentially expressed in certain tissues. With the recently developed ‘high throughput degradome sequencing’ approach, 21 target mRNAs of known miRNAs were identified for the first time in cucumber. These targets were associated with development, reactive oxygen species scavenging, signaling transduction and transcriptional regulation. Our study provides an overview of miRNA expression profile and interaction between miRNA and target, which will help further understanding of the important roles of miRNAs in cucumber plants

Biomedical applications of natural-based polymers combined with bioactive glass nanoparticles

In recent years, the combination of natural polymers with nanoparticles has permitted the development of sophisticated and efficient bioinspired constructs. In this regard, the incorporation of bioactive glass nanoparticles (BGNPs) confers a bioactive nature to these constructs, which can then induce the formation of a bone-like apatite layer upon immersion in a physiological environment. Moreover, the incorporation of bioactive glass nanoparticles has been found to be beneficial; the constructs proved to be biocompatible, promote cell adhesion and spreading, and regulate osteogenic commitment. This review provides a summary and discussion of the composition, design, and applications of bioinspired nanocomposite constructs based on BGNPs. Examples of nanocomposite systems will be highlighted with relevance to biomedical applications. It is expected that understanding the principles and the stateof-the-art of natural nanocomposites may lead to breakthroughs in many research areas, including tissue engineering and orthopaedic devices. The challenges regarding the future translation of these nanostructured composites into clinical use are also summarized.A´lvaro J. Leite acknowledges the Portuguese Foundation for Science and Technology (FCT) for his doctoral grant (SFRH/BD/73174/2010).info:eu-repo/semantics/publishedVersio

The effect of composition on the electrochemical properties and corrosion of wrought Mg-alloys

Magnesium (Mg) alloys are attractive materials for the automotive industry due to their comparatively low density and high strength to weight ratio. However, the wider applications of Mg alloys, especially in wrought applications, are restricted by the combination of relatively poor corrosion resistance and limited formability. In this work, low-level additions of Zn, Ca, Gd, Sr and Zr were studied as alloying additions to Mg, owing to their beneficial effects on improving the strength and formability. The alloys designed and presented herein are unique to date, owing to: (a) the total alloy loading being relatively low, resulting in the low density and low cost; (b) the microstructures being nominally homogeneous, essential for good formability; (c) the alloys are heat treatable and amenable to an increase in strength after wrought processing, for example a paint bake cycle (noting that the existing commercial wrought alloys such as the ZK and AZ alloys are not heat treatable). Due the alloy compositions used in this work being new, the electrochemical properties of such alloys were not previously understood. Since the corrosion of Mg alloys depends on the alloying additions, the study herein aims to principally investigate the compositional and processing effects on the corrosion of Mg. To do this, significant aspets of alloy production and processing on the laboratory scale are required. Herein, additions of Zn, Ca, Zr, Gd and Sr to Mg were deliberately made in binary, ternary, quaternary and quinternary combinations to systematically explore the effects of altering bulk chemistry on the corrosion of Mg. Microhardness testing was employed to estimate the strength of Mg alloys. Results were correlated with microstructure analysis. This thesis contributes to an understanding of the corrosion of Mg alloys with relatively low alloy loadings, which is also lacking in the literature. The results reveal that (i) hardness increased with alloy loading; whilst the corrosion rates did not show clear relationship with alloy loading; (ii) Mg alloys instead had an ultra-sensitivity to the type of alloying additions, and most elements promoted higher corrosion rates than pure Mg due to enhanced cathodic kinetics; (iii) alloys with multiple alloying additions (quaternary and quinternary) tolerated relatively higher alloy loading without much deteriorations on the corrosion resistance. An artificial neural network (ANN) model was used to manage, interpret and disseminate the datasets in a holistic framework

The effect of composition on the electrochemical properties and corrosion of wrought Mg-alloys

Magnesium (Mg) alloys are attractive materials for the automotive industry due to their comparatively low density and high strength to weight ratio. However, the wider applications of Mg alloys, especially in wrought applications, are restricted by the combination of relatively poor corrosion resistance and limited formability. In this work, low-level additions of Zn, Ca, Gd, Sr and Zr were studied as alloying additions to Mg, owing to their beneficial effects on improving the strength and formability. The alloys designed and presented herein are unique to date, owing to: (a) the total alloy loading being relatively low, resulting in the low density and low cost; (b) the microstructures being nominally homogeneous, essential for good formability; (c) the alloys are heat treatable and amenable to an increase in strength after wrought processing, for example a paint bake cycle (noting that the existing commercial wrought alloys such as the ZK and AZ alloys are not heat treatable). Due the alloy compositions used in this work being new, the electrochemical properties of such alloys were not previously understood. Since the corrosion of Mg alloys depends on the alloying additions, the study herein aims to principally investigate the compositional and processing effects on the corrosion of Mg. To do this, significant aspets of alloy production and processing on the laboratory scale are required. Herein, additions of Zn, Ca, Zr, Gd and Sr to Mg were deliberately made in binary, ternary, quaternary and quinternary combinations to systematically explore the effects of altering bulk chemistry on the corrosion of Mg. Microhardness testing was employed to estimate the strength of Mg alloys. Results were correlated with microstructure analysis. This thesis contributes to an understanding of the corrosion of Mg alloys with relatively low alloy loadings, which is also lacking in the literature. The results reveal that (i) hardness increased with alloy loading; whilst the corrosion rates did not show clear relationship with alloy loading; (ii) Mg alloys instead had an ultra-sensitivity to the type of alloying additions, and most elements promoted higher corrosion rates than pure Mg due to enhanced cathodic kinetics; (iii) alloys with multiple alloying additions (quaternary and quinternary) tolerated relatively higher alloy loading without much deteriorations on the corrosion resistance. An artificial neural network (ANN) model was used to manage, interpret and disseminate the datasets in a holistic framework

MAGNETIC FIELD INDUCED BY WAKE OF MOVING BODY IN WIND WAVES (Invited Paper)

A general procedure to evaluate the electromagnetic fields generated by moving seawater through the geomagnetic field is proposed. It contains two essential steps: modeling of velocity vector of seawater according to its dynamic mechanism, and solution of Maxwell equations under a stratified ocean configuration. Two kinds of motions are considered in this work, wind-driven waves and wakes due to a moving body. The ocean is taken to be infinitely deep at the moment. Both the velocity vector and magnetic field are expressed as superposition of sinusoidal waves. Simulation results show that the magnetic fields produced by moderate wind waves or a typical size body moving at moderate speed are on the order of a few hundred pico-Tesla near the sea level. The spectrum characteristics of the two kind magnetic anomalies are distinct.Engineering, Electrical & ElectronicPhysics, AppliedTelecommunicationsSCI(E)[email protected]