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Radialenes and expanded radialenes are cross‐conjugated macrocycles displaying poor aromatic character. In this work, three 9‐fluorenylidene substituted expanded [n]radialenes (ER‐n, n=3–5) with a diacetylene spacer were synthesized and their structures were confirmed by X‐ray crystallographic analysis and NMR spectroscopy. They all can be easily reduced into relatively stable dianions. Detailed experimental measurements and theoretical calculations suggest that their dianions (ER‐n2−, n=3–5) are stabilized by both the aromatic fluorenyl anion substituents and the central aromatic rings with formally [4n+2] delocalized π electrons. In addition, the dianions of the extended radialenes (ER‐42− and ER‐52−) show unique open‐shell diradical character with a small singlet‐triplet energy gap. For comparison, their linear counterparts (L‐3 and L‐4) were also synthesized; their dianions exhibit very different redox and optical properties from their respective macrocycles. [ABSTRACT FROM AUTHOR]

Radialenes and expanded radialenes are cross‐conjugated macrocycles displaying poor aromatic character. In this work, three 9‐fluorenylidene substituted expanded [n]radialenes (ER‐n, n=3–5) with a diacetylene spacer were synthesized and their structures were confirmed by X‐ray crystallographic analysis and NMR spectroscopy. They all can be easily reduced into relatively stable dianions. Detailed experimental measurements and theoretical calculations suggest that their dianions (ER‐n2−, n=3–5) are stabilized by both the aromatic fluorenyl anion substituents and the central aromatic rings with formally [4n+2] delocalized π electrons. In addition, the dianions of the extended radialenes (ER‐42− and ER‐52−) show unique open‐shell diradical character with a small singlet‐triplet energy gap. For comparison, their linear counterparts (L‐3 and L‐4) were also synthesized; their dianions exhibit very different redox and optical properties from their respective macrocycles. [ABSTRACT FROM AUTHOR]

In order to realise the biocompatibility and antibacterial activity of Ti alloy to meet the requirements of oral and orthopaedic applications, drug-loaded hydroxyapatite coatings doped with strontium were designed and constructed on the surface of Ti alloy using layer-by-layer assembly and hydrothermal treatment. The obtained coating was characterised by Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy. The biological assays showed that the composite coating exhibited excellent biocompatibility and antibacterial activity. Therefore, based on the in vitro studies, it can be claimed that the LbL assembly and the multifunctional coating can act as a promising surface-engineering strategy for the functionalization of Ti alloy in clinical trials. [ABSTRACT FROM AUTHOR]

Carbohydrates have gained a lot of appreciation in the past few decades due to their important roles in numerous biological events. Acquiring a structurally well‐defined carbohydrate compound is essential for the understanding of its functions. Although some innovative methods have been developed for the synthesis of complex oligosaccharides, glycan synthesis is in general still a time‐consuming and difficult work. Herein, we will introduce the preactivation‐based glycosylation strategy, which is an efficient protocol independent of the reactivity of glycosyl donor. This review will focus on summarizing the versatile applications of preactivation strategy in stereoselective glycosylation and one‐pot assembly of biologically important oligosaccharides and even polysaccharides. What is the most favorite and original chemistry developed in your research group? Preactivation‐based one‐pot glycosylation strategy and applications. How do you get into this specific field? Could you please share some experiences with our readers? I got into this field when I was a research associate in 1996. My supervisor, Prof. Chi‐Huey Wong, gave me a research topic for synthesis of oligosaccharide libraries. At that moment, as a beginner, I did not know too much carbohydrate chemistry, just to learn and to do it. The importance and challenge of carbohydrates attracted me. What is the most important personality for scientific research? Curiosity, passion, and creative thinking. How do you supervise your students? In my opinion, before the graduate students start a specific project, their experimental skills need to be well trained. During the period of graduate studies, the enhancement of abilities to analyze problems and to solve problems is very important. The graduate students should always keep an eye on the unusual experimental phenomena. What's your hobbies? Reading history books. What is your favorite journals? The journals publishing the latest research works in chemistry and medical science. [ABSTRACT FROM AUTHOR]

Carbohydrates play important roles in life science, but their synthesis is always hampered by their complicated chemical structures. Scientists have never stopped trying to solve the problem of glycan synthesis from various aspects. Here a brief overview of recent progress in glycan synthesis, including chemical approaches, chemoenzymatic approaches, and automated synthesis, will be discussed, focusing on the efficiency of new glycosylation methods, the stereoselectivity of coupled products, and their applications in the assembly of complex glycan chains. [ABSTRACT FROM AUTHOR]

Background. The aim of this study was to investigate the effects of human umbilical cord mesenchymal stem cell activated by curcumin (hUC-MSCs-CUR) on Parkinson's disease (PD). hUC-MSCs can differentiate into many types of adult tissue cells including dopaminergic (DA) neurons. CUR could protect DA neurons from apoptosis induced by 6-hydroxydopamine (6-OHDA). Therefore, we used the hUC-MSCs activated by CUR for the treatment of PD in an animal model. Methods. The hUC-MSCs-CUR was transplanted into the MPTP-induced PD mouse models via the tail vein. We found that hUC-MSCs-CUR significantly improved the motor ability, increased the tyrosine hydroxylase (TH), dopamine (DA), and Bcl-2 levels, and reduced nitric oxide synthase, Bax, and cleaved caspase 3 expression in PD mice. The supernatant of hUC-MSCs-CUR (CM-CUR) was used to stimulate the SH-SY5Y cellular model of PD; cell proliferation, differentiation, TH, and neuronal-specific marker microtubular-associated protein 2 (MAP2) expressions were examined. Results. Our data showed that CM-CUR significantly promoted cell proliferation and gradually increased TH and MAP2 expression in SH-SY5Y PD cells. The beneficial effects could be associated with significant increase of rough endoplasmic reticulum in the hUC-MSCs-CUR, which secretes many cytokines and growth factors beneficial for PD treatment. Conclusions. Transplantation of hUC-MSCs-CUR could show promise for improving the motor recovery of PD. [ABSTRACT FROM AUTHOR]

Background. The prevalence of overweight/obesity in adults is raised to 39%, which is nearly tripled more than 1975. The alteration of the gut microbiome has been widely accepted as one of the main causal factors. To find an effective strategy for the prevention and treatment of overweight/obesity, a systematic review and meta-analysis were designed. Methods. In this study, we systematically reviewed the article published from January 2008 to July 2018 and conducted a meta-analysis to examine the effects of probiotics on body weight control, lipid profile, and glycemic control in healthy adults with overweight or obesity. The primary outcomes were body weight, body mass index (BMI), waist circumference, fat mass, fat percentages, plasma lipid profiles, and glucose metabolic parameters. Results. We systematically searched PubMed, Embase, and the Web of Science and identified 1248 articles, and 7 articles which were manually searched by the references of included studies and previously systematic reviews. Twelve randomized controlled trials (RCTs), including 821 participants, were included in the meta-analysis via full-text screening. Probiotics supplementation resulted in a statistical reduction in body weight (WMD [95% CI]; -0.55 [-0.91, -0.19] kg), BMI (WMD [95% CI]; -0.30 [-0.43, -0.18] kg m−2), waist circumference (WMD [95% CI]; -1.20 [-2.21, -0.19] cm), fat mass (WMD [95% CI]; -0.91 [-1.19, -0.63] kg), and fat percentage (WMD [95% CI]; -0.92 [-1.27, -0.56] %) compared with control groups. As expected, the metabolic parameters were improved significantly, with a pooled standardized mean difference in TC (SMD [95% CI]; -0.43 [-0.80, -0.07]), LDL-C (SMD [95% CI]; -0.41 [-0.77, -0.04]), FPG (SMD [95% CI]; -0.35 [-0.67, -0.02]), insulin (SMD [95% CI]; -0.44 [-0.84, -0.03]), and HOMA-IR (SMD [95% CI]; -0.51 [-0.96, -0.05]), respectively. The changes in TG (SMD [95% CI]; 0.14 [-0.23, 0.50]), HDL-C (SMD [95% CI]; -0.31 [-0.70, 0.07]), and HbA1c (SMD [95% CI]; -0.23 [-0.46, 0.01]) were not significant. Conclusion. This study suggests that the probiotics supplementation could potentially reduce the weight gain and improve some of the associated metabolic parameters, which may become an effective strategy for the prevention and treatment of obesity in adult individuals. [ABSTRACT FROM AUTHOR]

Introduction. Gliomas are infiltrative neoplasms of a highly invasive nature. Different stages of gliomas feature distinct genomic, genetic, and epigenetic changes. The long noncoding RNA Growth Arrest Specific Transcript 5 (GAS5) is an identified tumour suppressor involved in several cancers. However, the underlying roles of the GAS5 gene in lower-grade glioma (LGG) patients are not clear. Methods. Via bioinformatic analysis based on TCGA-LGG and TCGA-GBM data, we explored the mechanisms of GAS5 expression in LGG (grades II and III) and high-grade glioma (glioblastoma multiforme, grade IV). The log-rank test and multivariate Cox analysis were performed to find the association between GAS5 and overall survival (OS) in LGG patients. Weighted gene coexpression network analysis (WGCNA) and RNA-Seq analysis were applied to find the key gene network associated with GAS5. Results. We found that GAS5 expression was downregulated in both LGG and glioblastoma multiforme (GBM) compared with normal brain tissue. Low methylation in the GAS5 promoter region was detected in both LGG and GBM tissues. The amplification type was the predominant type of GAS5 gene alteration in both LGG and GBM. High GAS5 expression was more associated with long overall survival (OS) in LGG patients than in GBM patients. The multivariate survival analysis of GAS5 and clinical and molecular characteristics in LGG patients further confirmed the association between GAS5 and OS in LGG patients. We then developed a nomogram for clinical use. WGCNA and RNA-Seq analysis indicated that ribosomal biogenesis and translation initiation were the predominant events regulated by GAS5 in LGG patients. Conclusion. Taken together, these results demonstrate that GAS5 expression is associated with OS in LGG patients and that its underlying roles involve the regulation of ribosomal biogenesis and translation initiation, which may aid in identifying a new target for the treatment of LGG. [ABSTRACT FROM AUTHOR]

The chirality of supramolecular polymeric materials is subtly affected by a delicate balance among various non‐covalent interactions, the details of which are inadequately understood. Now, a fine balance of intermolecular interactions, including closed‐shell metal–metal, dispersive and electrostatic interactions, is used to direct the delicate orientation of monomeric building blocks, thereby achieving the successful preparation of different nanostructures with distinct supramolecular chirality. Moreover, kinetically trapped and thermodynamically stable aggregates were monitored over time in the supramolecular polymerization of cationic PtII complexes. The dynamic self‐assembly process can be successfully controlled by modifying the counteranion and solvent composition. A chiral doping approach can also be used to induce the chirality of an achiral PtII complex at the supramolecular level. The chirality transfer process and the pathway complexity of a series of chiral pincer‐type PtII complexes are described. A chiral doping approach can be used to induce the chirality of an achiral PtII complex at the supramolecular level. [Pt]=PtII complex; counteranion X−. [ABSTRACT FROM AUTHOR]

The chirality of supramolecular polymeric materials is subtly affected by a delicate balance among various non‐covalent interactions, the details of which are inadequately understood. Now, a fine balance of intermolecular interactions, including closed‐shell metal–metal, dispersive and electrostatic interactions, is used to direct the delicate orientation of monomeric building blocks, thereby achieving the successful preparation of different nanostructures with distinct supramolecular chirality. Moreover, kinetically trapped and thermodynamically stable aggregates were monitored over time in the supramolecular polymerization of cationic PtII complexes. The dynamic self‐assembly process can be successfully controlled by modifying the counteranion and solvent composition. A chiral doping approach can also be used to induce the chirality of an achiral PtII complex at the supramolecular level. [ABSTRACT FROM AUTHOR]

Abstract: A large quantity of polysaccharide‐derived conjugate vaccines have been developed to combat various pathogenic infections. Another prominent polysaccharide, heparin, is listed as an essential drug by the World Health Organization (WHO) to treat thrombus. One of their common problems is that they all derive from natural polysaccharides. Specifically, capsular polysaccharides are mainly obtained from bacterial fermentation and unfractionated heparin is extracted from animal tissues such as porcine mucosa. The quality of natural polysaccharides is inconsistent and traces of contamination would cause a disaster. By contrast, the use of chemical or chemoenzymatic methods could provide structurally homogeneous and quality‐controlled glycans. To date, large numbers of polysaccharide fragments and their analogues have been synthesized and evaluated. Some of them even showed comparable activities to their corresponding natural polysaccharides. Here, the latest advances in these synthetic glycan analogues ranging from carbohydrate‐based vaccines, heparin‐related therapeutics and glycomimetics of polysaccharides are summarized. [ABSTRACT FROM AUTHOR]

A diversity-oriented synthetic strategy was developed for the total synthesis of kainoid amino acids, which led to the enantioselective synthesis of (−)-kainic acid and the first total synthesis of (+)-acromelic acid C. Rh(i)-catalyzed asymmetric enyne cycloisomerization served as the key reaction in this strategy for the rapid construction of highly functionalized lactam, and the resulting vinyl acetate moiety was further utilized as a versatile building block for the installation of both isopropylidene and 2-pyridone units existing in natural kainoids. [ABSTRACT FROM AUTHOR]

Three new iminosugar-containing KRN7000 (also referred to as α- GalCer) analogues were designed and synthesized. In the design, the galactose moiety of KRN7000 was replaced by iminosugars and the iminosugar structures were connected with ceramide in different manners with a C-glycosidic bond instead of the O-glycosidic bond. To our knowledge, this is the first report in which iminosugars are incorporated in KRN7000 structure modifications. The synthetic compounds were evaluated for their ability to stimulate cytokine release. The results may benefit better understanding of structure-activity relationships and facilitate future design of more KRN7000 derivatives. [ABSTRACT FROM AUTHOR]

An experimental platform was built for the atmospheric turbulence simulation upon a liquid crystal spatial light modulator. The phase-only spatial light modulator is driven by a series of dynamic phase screens that have non-Kolmogorov turbulence characteristics. After passing through the simulated non-Kolmogorov turbulence, the angle-of-arrival (AoA) and light intensity of the laser beam were analyzed statistically. The variation trends of the AoA fluctuation and the scintillation index exhibited by the experimental results are in accordance with the theoretical predictions. Although there was some divergence between the experiments and theory that needs to be improved further, the experimental data demonstrate the feasibility of using the platform to simulate the turbulence influence on laser communication in the lab. [ABSTRACT FROM AUTHOR]

Apoplastic ascorbate oxidase (AO) plays significant roles in plant cell growth. However, the mechanism of underlying the transcriptional regulation of AO in Gossypium hirsutum remains unclear. Here, we obtained a 1,920-bp promoter sequence from the Gossypium hirsutum ascorbate oxidase (GhAO1) gene, and this GhAO1 promoter included a number of known cis-elements. Promoter activity analysis in overexpressing pGhAO1::GFP-GUS tobacco (Nicotiana benthamiana) showed that the GhAO1 promoter exhibited high activity, driving strong reporter gene expression in tobacco trichomes, leaves and roots. Promoter 5’-deletion analysis demonstrated that truncated GhAO1 promoters with serial 5’-end deletions had different GUS activities. A 360-bp fragment was sufficient to activate GUS expression. The P-1040 region had less GUS activity than the P-720 region, suggesting that the 320-bp region from nucleotide -720 to -1040 might include a cis-element acting as a silencer. Interestingly, an auxin-responsive cis-acting element (TGA-element) was uncovered in the promoter. To analyze the function of the TGA-element, tobacco leaves transformed with promoters with different 5’ truncations were treated with indole-3-acetic acid (IAA). Tobacco leaves transformed with the promoter regions containing the TGA-element showed significantly increased GUS activity after IAA treatment, implying that the fragment spanning nucleotides -1760 to -1600 (which includes the TGA-element) might be a key component for IAA responsiveness. Analyses of the AO promoter region and AO expression pattern in Gossypium arboreum (Ga, diploid cotton with an AA genome), Gossypium raimondii (Gr, diploid cotton with a DD genome) and Gossypium hirsutum (Gh, tetraploid cotton with an AADD genome) indicated that AO promoter activation and AO transcription were detected together only in D genome/sub-genome (Gr and Gh) cotton. Taken together, these results suggest that the 1,920-bp GhAO1 promoter is a functional sequence with a potential effect on fiber cell development, mediated by TGA-element containing sequences, via the auxin-signaling pathway. [ABSTRACT FROM AUTHOR]

A series of phosphorescent Au(i) bis(N-heterocyclic allenylidene) complexes, namely [Au(=C=C=CR1R2)2]+X−, were synthesized and structurally characterized. These organometallic complexes exhibit panchromatic transient absorption upon electronic photo-excitation and can self-organize into lyotropic chromonic mesophases in aqueous solutions. [ABSTRACT FROM AUTHOR]

Iminosugars are an extremely interesting and versatile class of compounds and have many potential therapeutic applications. However, the use of iminosugar derivatives as immunomodulating agents is an area that is less explored. This review describes recent advances in the field of iminosugars as immunomodulating agents with a particular emphasis on 1-deoxynojirimycin analogues and related compounds. Both chemical and biological aspects concerning their preparation and/or occurrence in nature, as well as their immunomodulatory properties, are discussed. [ABSTRACT FROM AUTHOR]

Ultraviolet photodetectors have been fabricated from ZnO quantum dots/carbon nanodots hybrid films, and the introduction of carbon nanodots improves the performance of the photodetectors greatly. The photodetectors can be used to detect very weak ultraviolet signals (as low as 12 nW/cm2). The detectivity and noise equivalent power of the photodetector can reach 3.1 × 1017 cmHz1/2/W and 7.8 × 10-20 W, respectively, both of which are the best values ever reported for ZnO-based photodetectors. The mechanism for the high sensitivity of the photodetectors has been attributed to the enhanced carrier-separation at the ZnO/C interface. [ABSTRACT FROM AUTHOR]

A low-temperature sol-gel process associated with different surfactants in ethanol solvent was applied to prepare ultrafine MnO2 nanowires and nanorods. The surfactants used in the synthesis procedure are crucial for the structure of products. Highly dispersed MnO2 nanowires was formed by assistance of cetyltrimethyl ammonium bromide while hierarchical particles assembled with nanowires were synthesized by usage of pluronic P123 triblock copolymer or Polyvinyl pyrrolidone. The free-standing sheet like structure aggregated with nanorods was obtained by using sodium dodecyl sulfate as a surfactant. All samples were characterized by SEM, TEM, XRD and the results indicated these MnO2 ultrafine nanostructures could be expediently produced by this facile method. [ABSTRACT FROM AUTHOR]

This paper presented a fast fine C/A code acquisition scheme of GPS signal based on averaging correlation technique. In the proposed scheme, it sampled the received IF signal and the local C/A replica code at a high sampling frequency, then both of them were dealt with averaging process and the value of correlation energy could be calculated by the 1 024-point FFT processor. It reduced the computational complexity in the proposed scheme to about 1/22 compared with the FFT-based code acquisition scheme without averaging process. It could realize the purpose of rapid acquisition. It improved the acquisition sensitivity of the proposed scheme theoretically by about 2. 2 dB, compared to the conventional acquisition scheme with acquisition precision of half a chip. Finally, simulations performe to verify the feasibility of the proposed scheme. [ABSTRACT FROM AUTHOR]

High Mg-content single-phase wurtzite MgZnO alloys with a bandgap of 4.35 eV have been obtained on sapphire substrate by introducing a composition-gradient MgxZn1–xO buffer layer. By employing the accelerated electrons obtained in a solid-state structure as an excitation source, an emission at around 285 nm, which is originated from the near-band-edge emission of the Mg0.51Zn0.49O active layer, has been observed. The results reported in this paper may provide a promising route to high performance deep-ultraviolet light-emitting devices by bypassing the challenging doping issues of wide bandgap semiconductors. [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD) is a neurodegenerative movement disorder that is characterized by the progressive degeneration of the dopaminergic (DA) pathway. Mesenchymal stem cells derived from human umbilical cord (hUC-MSCs) have great potential for developing a therapeutic agent as such. HGF is amultifunctionalmediator originally identified in hepatocytes and has recently been reported to possess various neuroprotective properties. This study was designed to investigate the protective effect of hUC-MSCs infected by an adenovirus carrying the HGF gene on the PD cell model induced byMPP+ on human bone marrow neuroblastoma cells. Our results provide evidence that the cultural supernatant from hUC-MSCs expressing HGF could promote regeneration of damaged PD cells at higher efficacy than the supernatant from hUC-MSCs alone. And intracellular free Ca2+ obviously decreased after treatment with cultural supernatant from hUC-MSCs expressing HGF, while the expression of CaBP-D28k, an intracellular calcium binding protein, increased. Therefore our study clearly demonstrated that cultural supernatant of MSC overexpressing HGF was capable of eliciting regeneration of damaged PD model cells. This effect was probably achieved through the regulation of intracellular Ca2+ levels by modulating of CaBP-D28k expression. [ABSTRACT FROM AUTHOR]

The wavelet analysis can he used to disclose the evolution law of drought disaster ratio time series (DDRTS), which is important to the drought disaster early warning. Based on the wavelet and fractal analysis on the 59 years time series of drought disaster ratio in China, the original time series was decomposed and reconstructed using Mallat multi-resolution wavelet algorithm. The fractal analysis results showed that the Chinese DDRTS had obvious fractal characteristics, which minimum embedding dimension is six. The multi-resolution wavelet analysis results showed that the Chinese DDRTS had obvious multi-period characteristics, which the 30-35 years change period has maximum energy density. The following conclusions can be drawn. 1) The minimum embedding dimension of fractal analysis can be served as a maximum effective decompose level for the Mallat multi-resolution wavelet analysis, which is helpful to enlarge the application field of fractal analysis. 2) The evolution of Chinese DDRTS was driven by six independent state variables, and had obvious multi-period characteristic. As a whole, the drought disaster ratio remained to be in a growth period at present. [ABSTRACT FROM AUTHOR]

By employing lithium and nitrogen codoping method, p-type zinc oxide (ZnO) films have been prepared, and the p-type conduction can maintain for 207 days. ZnO p-n junctions have been constructed based on the p-type ZnO. Under the drive of continuous current, obvious emission has been observed from the p-n junctions, and the ZnO p-n junction light-emitting devices (LEDs) can still work after placing in air ambient for 180 days. Room temperature electroluminescence spectra of the p-ZnO:(Li,N)/n-ZnO structured LEDs under continuous current recorded intermittently for 180 days. [ABSTRACT FROM AUTHOR]

The bright side of triple double bonds: Two series of stable tridentate cyclometalated PtII and AuIII allenylidene complexes were found to exhibit many functionalities, such as long‐lived excited states, self‐assembly into supramolecular nanostructures, DNA and nucleus binding and cellular imaging capabilities (see figure). [ABSTRACT FROM AUTHOR]

Abstract: In this work, a facile and rapid microwave-assisted hydrothermal route has been developed to prepare Bi2GeO5 nanoflakes. Ag nanoparticles were subsequently deposited on the Bi2GeO5 nanoflakes by a photoreduction procedure. The phases and morphologies of the products were characterized by powder X-ray diffraction (XRD), X-ray photoelectron spectrum (XPS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and UV–vis diffuse reflectance spectroscopy. Photocatalytic experiments indicate that such Ag/Bi2GeO5 nanocomposite possesses higher photocatalytic activity for RhB degradation under UV light irradiation in comparison to pure Bi2GeO5. The amount of Ag in the nanocomposite affects the catalytic activity, and 3wt% Ag showed the highest photodegradation efficiency. Moreover, the catalyst remains active after four consecutive tests. The present study provides a new strategy to design composite materials with enhanced photocatalytic activity. [Copyright &y& Elsevier]

Abstract: Ganglioside GM3 and its derivatives have many important biological functions. Using diethyl phosphite protected sialic acid as glycosyl donor and 3,2′,3′,4′-unprotected lactose as glycosyl acceptor, the sialic acid-containing trisaccharide was assembled with excellent anomeric stereoselectivity. The trisaccharide was further coupled with ceramide precursor to yield sphingosine 1. Based on this key intermediate, two different series of N-modified GM3 analogues with modifications on either the nitrogen of sialic acid residue or the nitrogen of ceramide moiety and GM3 itself were synthesized smoothly. [Copyright &y& Elsevier]

To increase the responsivity is one of the vital issues for a photodetector. By employing ZnO as a representative material of ultraviolet photodetectors and Si as a representative material of visible photodetectors, an impact ionization process, in which additional carriers can be generated in an insulating layer at a relatively large electric field, has been employed to increase the responsivity of a semiconductor photodetector. It is found that the responsivity of the photodetectors can be enhanced by tens of times via this impact ionization process. The results reported in this paper provide a general route to enhance the responsivity of a photodetector, thus may represent a step towards high-performance photodetectors. [ABSTRACT FROM AUTHOR]

A mild method for the synthesis of α-C-glycosides by the samarium diiodide mediated coupling reactions of glycosyl 2-pyridyl sulfones with different α,β-unsaturated carbonyl compounds has been developed. This method allows the use of less amount of substrates. [ABSTRACT FROM AUTHOR]

Saccharides are polyhydroxy compounds, and their synthesis requires complex protecting group manipulations. Protecting groups are usually used to temporarily mask a functional group which may interfere with a certain reaction, but protecting groups in carbohydrate chemistry do more than protecting groups usually do. Particularly, protecting groups can participate in reactions directly or indirectly, thus affecting the stereochemical outcomes, which is important for synthesis of oligosaccharides. Herein we present an overview of recent advances in protecting groups influencing stereoselectivity in glycosylation reactions, including participating protecting groups, and conformation-constraining protecting groups in general. [ABSTRACT FROM AUTHOR]

Abstract: The repeating GalpNAc-α-(1→4)-GalpNAc unit is part of a series of essential structures that can be found in many important biomolecules such as the glycoproteins and the O-antigenic polysaccharides of clinically important bacterial strains. In this paper, we describe an exclusive α-selective glycosylation reaction, using a 4,6-di-O-tert-butyldimethylsilyl-N-acetyloxazolidinone-protected thioglycoside as the glycosyl donor, under pre-activation conditions, with only half amount of the promoter, providing the product GalpNAc-α-(1→4)-GalpNAc in high isolated yield. This reaction can be also applied to increasing the length of the repeating structure, which is of significant use in further synthesis of branched or linear oligosaccharides. [ABSTRACT FROM AUTHOR]

Abstract: A new sialyl donor, N,N-acetyl, benzoyl-O-perbenzoyl-protected p-toluenethiosialoside, was synthesized and its sialylation reaction was investigated. This reaction proceeded in dichloromethane and β anomeric selectivity was achieved when NIS–TfOH was used as promoter. This method may be employed to construct the unnatural β-linked sialosides. [Copyright &y& Elsevier]

NaHSO4�SiO2 was used as an efficient heterogeneous catalyst for both the formation and the cleavage of benzylidene �acetals. This catalyst is compatible with many functional or protective groups. Under different solvent systems, either the formation or the cleavage of benzylidene acetals was carried out smoothly in �excellent yields and with good chemoselectivity. [ABSTRACT FROM AUTHOR]

We have investigated the effects of two heat shock proteins, Hsp10 and Hsp60, on insulin-like growth factot-1 receptor (IGF-1R) signaling in cardiac muscle cells. Neonatal cardiomyocytes were transduced with Hsp10 or Hsp60 via adenoviral vector. Compared with the cells transduced with a control vector, overexpression of Hsp10 or Hsp60 increased the abundance of IGF-1R and IGF-1-stimulated receptor autophosphorylation. Thus, Hsp10 and Hsp60 overexpression increased the number of functioning receptors and amplified activation of IGF-1R signaling. IGF-1 stimulation of MEK, Erk, p90Rsk, and Akt were accordingly augmented. Transducing cardiomyocytes with antisense Hsp60 oligonucleotides reduced Hsp60 expression, decreased the abundance of IGF-1R, attenuated IGF-1R autophosphorylation, and suppressed the pro-survival action of IGF-1 in cardiomyocytes. Using cycloheximide to inhibit protein synthesis did not alter the effect of Hsp60 on IGF-1R signaling, and IGF-1R mRNA levels were not up-regulated by Hsp10 or Hsp60. Additional experiments showed that Hsp10 and Hsp60 suppressed polyubiquitination of IGF-1 receptor. These data indicate that Hsp10 and Hsp60 can modulate IGF-1R signaling through post-translational modification. In animal models of diabetes, diabetic myocardium is associated with decreased abundance of Hsp60, increased ubiquitination of IGF-1R, and lower level of IGF-1R protein. Declined myocardial protection is a major feature of diabetic cardiomyopathy. These data suggest that decreased Hsp60 expression and subsequent decline of IGF-1R signaling may be a fundamental mechanism underlying the development of diabetic cardiomyopathy. [ABSTRACT FROM AUTHOR]

Reports that the assembly of an oligosaccharide library has been achieved in a practical and efficient manner. Application of a one-pot sequential approach; Rapid assembly of 33 linear or branched fully-protected oligosaccharides using designed building blocks; Deprotection of the oligosaccharides either partially or completely to create 29 more structures.

The heterogeneity of macrophages influences the response to immune checkpoint inhibitor (ICI) therapy. However, few studies explore the impact of APOE+ macrophages on ICI therapy using single‐cell RNA sequencing (scRNA‐seq) and machine learning methods. The scRNA‐seq and bulk RNA‐seq data are Integrated to construct an M.Sig model for predicting ICI response based on the distinct molecular signatures of macrophage and machine learning algorithms. Comprehensive single‐cell analysis as well as in vivo and in vitro experiments are applied to explore the potential mechanisms of the APOE+ macrophage in affecting ICI response. The M.Sig model shows clear advantages in predicting the efficacy and prognosis of ICI therapy in pan‐cancer patients. The proportion of APOE+ macrophages is higher in ICI non‐responders of triple‐negative breast cancer compared with responders, and the interaction and longer distance between APOE+ macrophages and CD8+ exhausted T (Tex) cells affecting ICI response is confirmed by multiplex immunohistochemistry. In a 4T1 tumor‐bearing mice model, the APOE inhibitor combined with ICI treatment shows the best efficacy. The M.Sig model using real‐world immunotherapy data accurately predicts the ICI response of pan‐cancer, which may be associated with the interaction between APOE+ macrophages and CD8+ Tex cells. [ABSTRACT FROM AUTHOR]

Phytopathogenic Fusarium graminearum poses significant threats to crop health and soil quality. Although our laboratory-cultivated Pseudomonas sp. P13 exhibited potential biocontrol capacities, its effectiveness against F. graminearum and underlying antifungal mechanisms are still unclear. In light of this, our study investigated a significant inhibitory effect of P13 on F. graminearum T1, both in vitro and in a soil environment. Conducting genomic, metabolomic, and transcriptomic analyses of P13, we sought to identify evidence supporting its antagonistic effects on T1. The results revealed the potential of P13, a novel Pseudomonas species, to produce active antifungal components, including phenazine-1-carboxylate (PCA), hydrogen cyanide (HCN), and siderophores [pyoverdine (Pvd) and histicorrugatin (Hcs)], as well as the dynamic adaptive changes in the metabolic pathways of P13 related to these active ingredients. During the logarithmic growth stage, T1-exposed P13 strategically upregulated PCA and HCN biosynthesis, along with transient inhibition of the tricarboxylic acid (TCA) cycle. However, with growth stabilization, upregulation of PCA and HCN synthesis ceased, whereas the TCA cycle was enhanced, increasing siderophores secretion (Pvd and Hcs), suggesting that this mechanism might have caused continuous inhibition of T1. These findings improved our comprehension of the biocontrol mechanisms of P13 and provided the foundation for potential application of Pseudomonas strains in the biocontrol of phytopathogenic F. graminearum. [ABSTRACT FROM AUTHOR]

In the paper, the possibility of two complete conversions is investigated, one is from the two‐photon hyperentangled Knill–Laflamme–Milburn (KLM) state to hyperentangled Bell states, the other is from three‐photon KLM state to the hyperentangled Greenberger–Horne–Zeilinger states, for photonic systems hyper‐encoded in polarization and spatial degrees of freedom assisted by error‐heralded quantum units (EHQUs). The system inhomogeneity and/or the imperfect photon scattering often restrict the performance of effective conversions of two types of hyperentangled states, and result in the reductions of the fidelity and the efficiency in tangible quantum information technologies. The polarization EHQU and spatial EHQU are two critical tools for actualizing two hyperentangled conversions in a heralded way, as the errors stemming from the system inhomogeneity and practically imperfect scattering are converted into efficacious responses of the detectors in our protocols. Thus, the fidelities of these conversion cases keep unchanged and have close to unity fidelities, which deepen the understanding of the properties of hyperentanglement. [ABSTRACT FROM AUTHOR]

Presents a strategy for the synthesis of unsymmetrically 3,4-disubstituted thiophenes utilizing 3,4-bis(trimethylsilyl)thiophene as a building block. Preparation of thiopenes; Generation of the 3,4-dihydrothiophene; Description of the utility of 3,4-bis(trimethylsilyl)thiopene.

Glycans have been hot topics in recent years due to their exhibition of numerous biological activities. However, the heterogeneity of their natural source and the complexity of their chemical synthesis impede the progress in their biological research. Thus, the development of glycan assembly strategies to acquire plenty of structurally well‐defined glycans is an important issue in carbohydrate chemistry. In this review, the latest advances in glycan assembly strategies from concepts to their applications in carbohydrate synthesis, including chemical and enzymatic/chemo‐enzymatic approaches, as well as solution‐phase and solid‐phase/tag‐assisted synthesis, are summarized. Furthermore, the automated glycan assembly techniques are also outlined. [ABSTRACT FROM AUTHOR]

By using Rb vapor filters, free-space quantum key distribution with the B92 protocol was realized experimentally; the filters based on the Faraday anomalous dispersion effect were used to suppress strong background light. With these atomic filters as spectral filtering, average transmission rates of sifted keys and corrected keys have reached as high as 3.14 and 1.56 kbits/s, respectively, while the error rate was maintained at a reasonable low level of 5.10%. The experimental results show that our Rb vapor filters with transmission efficiency of around 60% operate well under the condition of the mean photon number n≤0.1. [ABSTRACT FROM AUTHOR]

Simple Summary: In this study, we present the characterization of Aedes aegypti mosquito salivary protein, LTRIN (lymphotoxin β receptor inhibitor), a key facilitator of ZIKV transmission. Injected into the human host during blood-feeding, LTRIN interacts with the human receptor LTβR. We found that LTRIN exists as a thermostable protein with homodimers consisting of an alpha helix-dominant secondary structure with two EF-hand motifs, crucial for withstanding temperature fluctuations during blood-feeding. Despite being an EF-hand protein, its secondary structure remains unaffected by Ca2+ binding. ELISA assays and HDX-MS experiments identified the binding region of LTRIN with LTβR. Disrupting the calcium-binding ability in the second EF-hand motif significantly impacted the interaction between LTRIN, particularly the 15 kDa C-terminal protein, ΔLTRIN, and LTβR. Moreover, the decrease in binding affinity of full-length LTRIN suggests the presence of only the truncated form, ΔLTRIN, in the mosquito's saliva, as the N-terminal region likely covers the interaction site. This insight provides a basis for developing inhibitors against LTRIN as a potential treatment or vaccine target for ZIKV. Salivary proteins from mosquitoes have received significant attention lately due to their potential to develop therapeutic treatments or vaccines for mosquito-borne diseases. Here, we report the characterization of LTRIN (lymphotoxin beta receptor inhibitor), a salivary protein known to enhance the pathogenicity of ZIKV by interrupting the LTβR-initiated NF-κB signaling pathway and, therefore, diminish the immune responses. We demonstrated that the truncated C-terminal LTRIN (ΔLTRIN) is a dimeric protein with a stable alpha helix-dominant secondary structure, which possibly aids in withstanding the temperature fluctuations during blood-feeding events. ΔLTRIN possesses two Ca2+ binding EF-hand domains, with the second EF-hand motif playing a more significant role in interacting with LTβR. Additionally, we mapped the primary binding regions of ΔLTRIN on LTβR using hydrogen–deuterium exchange mass spectrometry (HDX-MS) and identified that 91QEKAHIAEHMDVPIDTSKMSEQELQFHY118 from the N-terminal of ΔLTRIN is the major interacting region. Together, our studies provide insight into the recognition of LTRIN by LTβR. This finding may aid in a future therapeutic and transmission-blocking vaccine development against ZIKV. [ABSTRACT FROM AUTHOR]

The efficient synthesis of N‐glycosides via direct N‐glycosylation of amides/azacycles has been reported. The glycosylation of amides/azacycles with glycosyl halides in the presence of a catalytic amount of urea proceeded smoothly to provide the corresponding N‐glycosylated amides or nucleosides in good to excellent yields with 1,2‐trans‐stereoselectivity. Moreover, by the addition of terpyridine, the 1,2‐cis‐stereoselectivity was achieved. [ABSTRACT FROM AUTHOR]

The article discusses research being done on the pharmaceutical importance of iminosugars. It references a study published in the 2016 issue of "Organic Letters," by Professor Xin-Shan Ye et al., which examined the adoption of a method for the chemical synthesis of nitro-polyols and their applications in the iminosugar synthesis. The variables considered include iminosugars as immunosuppressive agents, the chirality of glycals and the nitration of glucal and scission of the carbon-carbon bond.

The article discusses a method developed by Professor Xin-Shan Ye from Peking University and colleagues to achieve the synthesis of nitro-polyols and further explore their applications in the synthesis of iminosugars. Topics covered include a study of the capacity of iminosugar to act as molecular chaperones for treating Gaucher's disease and a description of several methods for the preparation of nitro-polyol derivatives.

The efficiency of targeted knock-in for cell therapeutic applications is generally low, and the scale is limited. In this study, we developed CLASH, a system that enables high-efficiency, high-throughput knock-in engineering. In CLASH, Cas12a/Cpf1 mRNA combined with pooled adeno-associated viruses mediate simultaneous gene editing and precise transgene knock-in using massively parallel homology-directed repair, thereby producing a pool of stably integrated mutant variants each with targeted gene editing. We applied this technology in primary human T cells and performed time-coursed CLASH experiments in blood cancer and solid tumor models using CD3, CD8 and CD4 T cells, enabling pooled generation and unbiased selection of favorable CAR-T variants. Emerging from CLASH experiments, a unique CRISPR RNA (crRNA) generates an exon3 skip mutant of PRDM1 in CAR-Ts, which leads to increased proliferation, stem-like properties, central memory and longevity in these cells, resulting in higher efficacy in vivo across multiple cancer models, including a solid tumor model. The versatility of CLASH makes it broadly applicable to diverse cellular and therapeutic engineering applications. Unbiased selection of CAR-T cells is achieved by massively parallel knock-in engineering. [ABSTRACT FROM AUTHOR]

The dried ripe fruit of Gardenia jasminoides Ellis was usually applied as an herb medicine in Traditional Chinese Medicine. It was suggested that the Gardenia jasminoides oil extract (oil from Fructus Gardeniae [OFG]) might serve as a potential treatment for depression, whereas its pathogenesis still remained not fully understood. The present research was conducted to evaluate the anti-depressive effect of OFG in mice and explore its potential mechanism. The OFG and ketamine (KET) were intragastrically and intraperitoneally treated, respectively. Thereafter, the animals were subjected to the behavior tests. The expressions of protein kinase A (PKA), brain derived neurotrophic factor (BDNF), cAMP response element-binding protein (CREB) in hippocampus were detected by Western blot. The selective PKA inhibitor H-89 was also applied to confirm the mechanism. As a result, OFG and KET treatment improved the behavior performance. Furthermore, the administrations of OFG effectively enhanced the expressions of PKA, p-CREB, and BDNF. With the application of selective PKA inhibitor H-89, the ameliorated effects caused by OFG were blocked, but not by KET. In conclusion, the presented work indicated that OFG-exerted protective effect on depression through PKA-CREB-BDNF signaling. [ABSTRACT FROM AUTHOR]

Review: 45 refs. [ABSTRACT FROM AUTHOR]

Objective. We aimed to investigate how the embryonic stem cell-related gene Oct3/4 changes during the injury-repair process of distal pulmonary epithelium induced by 5-fluorouracil (5-Fu). Methods. We have developed the lung injury model induced by 5-Fu and observed the dynamic changes of Oct3/4 by indirect immunofluorescence, Western blot, and quantitative real-time PCR. Immunofluorescence double staining was used to compare the positions of Oct3/4(+) cells and other reported alveolar epithelial stem cells. Results. Oct3/4(+) cells were not found in normal rat lung epithelial cells. However, after treatment with 5-Fu, Oct3/4(+) cells appeared at 12 h, reached the peak at 24 h, then decreased at 48 h, and eventually disappeared at 72 h. Oct3/4 was localized in the nucleus. We found that the sites of Clara cell secretory protein and surfactant protein-C dual positive cells were apparently different from Oct3/4(+) cells. Conclusions. Our results revealed that, in rat alveolar epithelium, expression of Oct3/4 could be induced after treatment with 5-Fu, then decreased gradually, and was silenced following the alveolar epithelial differentiation. We hold that Oct3/4(+) cells are lung stem cells, which can provide new evidence for identification and isolation of lung epithelial stem cells. [ABSTRACT FROM AUTHOR]