An efficient C-glycoside production platform enabled by rationally tuning the chemoselectivity of glycosyltransferases.

Despite the broad potential applications of C-glycosides, facile synthetic methods remain scarce. Transforming glycosyltransferases with promiscuous or natural O-specific chemoselectivity to C-glycosyltransferases is challenging. Here, we employ rational directed evolution of the glycosyltransferase MiCGT to generate MiCGT-QDP and MiCGT-ATD mutants which either enhance C-glycosylation or switch to O-glycosylation, respectively.

Surgical refinements and sensory and functional outcomes of using thinned sensate anterolateral thigh perforator flaps for foot and ankle reconstruction: A retrospective study.

To improve the use of sensate anterolateral thigh (ALT) flaps for foot and ankle reconstruction, we employed a thinned nerve-selective harvesting technique. The data of 31 patients in whom sensate ALT perforator flaps were transferred for reconstruction of soft-tissue defects in the foot and ankle were reviewed. Flaps were elevated with 2 refinements.

[New drug discovery and prospect of small nucleic acids derived from traditional Chinese medicine and natural medicine].

Small nucleic acid drugs mainly include small interfering RNA(siRNA), antisense oligonucleotide(ASO), microRNA(miRNA), messenger RNA(mRNA), nucleic acid aptamer(aptamer), and so on. Its translation or regulation can be inhibited by binding to the RNA of the target molecule. Due to its strong specificity, persistence, and curability, small nucleic acid drugs have received considerable attention in recent years.

Metagenomic analysis of individual mosquito viromes reveals the geographical patterns and drivers of viral diversity.

Mosquito transmitted viruses are responsible for an increasing burden of human disease. Despite this, little is known about the diversity and ecology of viruses within individual mosquito hosts. Here, using a meta-transcriptomic approach, we determined the viromes of 2,438 individual mosquitoes (81 species), spanning ~4,000 km along latitudes and longitudes in China.

Metagenomic analysis of individual mosquitos reveals the ecology of insect viruses.

Mosquito transmitted viruses are responsible for an increasing burden of human disease. Despite this, little is known about the diversity and ecology of viruses within individual mosquito hosts. Using a meta-transcriptomic approach, we analysed the virome of 2,438 individual mosquitos (79 species), spanning ~4000 km along latitudes and longitudes in China.

[Analysis of WRKY transcription factor family based on full-length transcriptome sequencing in Polygonatum cyrtonema].

WRKY transcription factor family plays an important role in plant growth and development, secondary metabolite synthesis, and biotic and abiotic stress responses. The present study performed full-length transcriptome sequencing of Polygonatum cyrtonema by virtue of the PacBio SMRT high-throughput platform, identified the WRKY family by bioinformatics methods, and analyzed the physicochemical properties, subcellular localization, phylogeny, and conserved motifs. The results showed that 30.

[Mystery of Yiyin decoction theory: rule discovery and evaluation strategy of atypical pharmacological effects of Chinese medicinal prescription].

Yi Yin, a famous medical scientist and culinary master in the late Xia Dynasty and early Shang Dynasty, developed the Chinese medicinal liquids and Chinese medicinal prescriptions emerged after that. Chinese medicinal prescriptions have attracted much attention because of their unique advantages in the treatment of chronic multifactorial diseases, representing an important direction of drug discovery in the future. Yiyin decoction theory is the superior form of personalized combined medication with advanced consciousness.

Recent insights into oxidative metabolism of quercetin: catabolic profiles, degradation pathways, catalyzing metalloenzymes and molecular mechanisms.

Quercetin is the most abundant polyphenolic flavonoid (flavonol subclass) in vegetal foods and medicinal plants. This dietary chemopreventive agent has drawn significant interest for its multiple beneficial health effects ("polypharmacology") largely associated with the well-documented antioxidant properties. However, controversies exist in the literature due to its dual anti-/pro-oxidant character, poor stability/bioavailability but multifaceted bioactivities, leaving much confusion as to its exact roles in vivo.

Cascade of C(sp)-H Addition to Carbonyl and C(sp)-CN/C(sp)-H Coupling Enabled by Brønsted Acid: Construction of Benzo[]carbazole Frameworks.

Herein, we report an unprecedented cascade reaction of C(sp)-H addition to carbonyl and the C(sp)-CN/C(sp)-H coupling of 2-(2-oxo-2-arylethyl)benzonitriles with indoles enabled by commercially available TsOH·HO. The protocol represents the first metal-free C(sp)-CN/C(sp)-H coupling, affording a new route for the synthesis of various benzo[]carbazole derivatives with a broad substrate scope, high yields, and simple conditions.

Deferoxamine Counteracts Cisplatin Resistance in A549 Lung Adenocarcinoma Cells by Increasing Vulnerability to Glutamine Deprivation-Induced Cell Death.

Glutamine, like glucose, is a major nutrient consumed by cancer cells, yet these cells undergo glutamine starvation in the cores of tumors, forcing them to evolve adaptive metabolic responses. Pharmacologically targeting glutamine metabolism or withdrawal has been exploited for therapeutic purposes, but does not always induce cancer cell death. The mechanism by which cancer cells adapt to resist glutamine starvation in cisplatin-resistant non-small-cell lung cancer (NSCLC) also remains uncertain.

Comprehensive Understanding of Fluoroacetate Dehalogenase-Catalyzed Degradation of Fluorocarboxylic Acids: A QM/MM Approach.

Fluorochemicals are persistent, bioaccumulative, and toxic compounds that are widely tributed in the environment. Developing efficient biodegradation strategies to decompose the fluorochemicals via breaking the inert C-F bonds presents a holistic challenge. As a promising biodegradation enzyme candidate, fluoroacetate dehalogenase (FAcD) has been reported as the only non-metallic enzyme to catalyze the cleavage of the strong C-F bond.

Progress in Stereoselective Construction of C-C Bonds Enabled by Aldolases and Hydroxynitrile Lyases.

The creation of C-C bonds is an effective strategy for constructing complex compounds from simple synthetic blocks. Although many methods have been developed for C-C bond construction, the stereoselective creation of new C-C bonds remains a challenge. The selectivities (enantioselectivity, regioselectivity, and chemoselectivity) of biocatalysts are higher than those of chemical catalysts, therefore biocatalysts are excellent candidates for use in stereoselective C-C bond formation.

Gastroesophageal varices in a patient presenting with essential thrombocythemia: A case report.

Background: Gastroesophageal varices are a rare complication of essential thrombocythemia (ET). ET is a chronic myeloproliferative neoplasm (MPN) characterized by an increased number of blood platelets.

Case Summary: A 46-year-old woman, who denied a history of liver disease, was admitted to our hospital on presentation of hematemesis.

P450-BM3-Catalyzed Sulfoxidation versus Hydroxylation: A Common or Two Different Catalytically Active Species?

While the mechanism of the P450-catalyzed oxidative hydroxylation of organic compounds has been studied in detail for many years, less is known about sulfoxidation. Depending upon the structure of the respective substrate, heme-Fe═O (Cpd I), heme-Fe(III)-OOH (Cpd 0), and heme-Fe(III)-HO (protonated Cpd 0) have been proposed as reactive intermediates. In the present study, we consider the transformation of isosteric substrates via sulfoxidation and oxidative hydroxylation, respectively, catalyzed by regio- and enantioselective mutants of P450-BM3 which were constructed by directed evolution.

Harnessing fluoroacetate dehalogenase for defluorination of fluorocarboxylic acids: in silico and in vitro approach.

Widely distributed fluorocarboxylic acids have aroused worldwide environmental concerns due to its toxicity, persistence, and bioaccumulation. Enzyme-based eco-friendly biodegradation techniques have become increasingly important in treating fluorocarboxylic acids. Here we utilized in silico and in vitro approaches to investigate the defluorination mechanism of fluoroacetate dehalogenase (FAcD) toward monofluoropropionic acids at atomic-level.

Exploiting Designed Oxidase-Peroxygenase Mutual Benefit System for Asymmetric Cascade Reactions.

A unique P450 monooxygenase-peroxygenase mutual benefit system was designed as the core element in the construction of a biocatalytic cascade reaction sequence leading from 3-phenyl propionic acid to ( R)-phenyl glycol. In this system, P450 monooxygenase (P450-BM3) and P450 peroxygenase (OleT) not only function as catalysts for the crucial initial reactions, they also ensure an internal in situ HO recycle mechanism that avoids its accumulation and thus prevents possible toxic effects. By directed evolution of P450-BM3 as the catalyst in the enantioselective epoxidation of the styrene-intermediate, formed from 3-phenyl propionic acid, and the epoxide hydrolase ANEH for final hydrolytic ring opening, ( R)-phenyl glycol and 9 derivatives thereof were synthesized from the respective carboxylic acids in one-pot processes with high enantioselectivity.

[Generalized science of Chinese material medica-from preventive treatment of disease to Chinese medicine health industry].

Based on the systematic summary of the results of the fourth general survey of traditional Chinese medicine resources, the cultivation of large varieties of Chinese material medica and the latest research on health industrial development, the novel concepts and scientific connotations of generalized science of Chinese material medica are put forward, and the basic ideas and methods of a new Chinese medicine academic system, the cultivation system of large varieties of Chinese medicinal materials and the application system of the large health industry are constructed. This kind of generalized science of Chinese material medica, rooted in the traditional Chinese culture and the theory of "preventive treatment of disease", can avoid the narrow prospect induced by the increasing specialization and refinement of knowledge of science of Chinese material medica. It will play an important role in the modernization, industrialization, internationalization of traditional Chinese medicine.

Role of FGF-2 Transfected Bone Marrow Mesenchymal Stem Cells in Engineered Bone Tissue for Repair of Avascular Necrosis of Femoral Head in Rabbits.

Background/aims: Avascular necrosis of the femoral head (ANFH) is the focus and difficulty of orthopedic diseases. Recently, tissue engineering bone for this disease has shown a good therapeutic effect. The aim of the present study was to investigate the therapeutic effect of basic fibroblast growth factor (FGF-2) as cytokines transfected bone marrow mesenchymal stem cells (BMSCs) in constructing tissue-engineered bone for avascular necrosis of the femoral head.

Spinal glucocorticoid receptor‑regulated chronic morphine tolerance may be through extracellular signal‑regulated kinase 1/2.

Opioid use has been limited in the treatment of chronic pain due to their side effects, including analgesic tolerance. Previous studies demonstrated that glucocorticoid receptors (GRs) may be involved in the development of chronic morphine tolerance; however, the mechanism remains unknown. It was hypothesized that the expression of spinal phosphorylated mitogen‑activated protein kinase [MAPK; phosphorylated extracellular signal‑regulated kinase (ERK)] is regulated through the spinal GRs, following chronic treatment with morphine.

[Effect of Electroacupuncture at "Zusanli"(ST 36) on the Expression of Ghrelin/cAMP/PKA in the Jejunum in Rats with Spleen Deficiency Syndrome].

Objective: To observe the effect of electroacupuncture (EA) at "Zusanli"(ST 36) on Ghrelin/cAMP/PKA expression in the jejunum in rats with spleen deficiency syndrome, so as to reveal its underlying mechanism in improving energy metabolism.

Methods: Forty male SD rats were randomly divided into 4 groups:normal group, spleen deficiency syndrome (model) group, EA group and non-acupoint group (=10 in each group).The model of spleen deficiency syndrome was established by improper diet and overstrain.

Insight into the effects of modifying chromophores on the performance of quinoline-based dye-sensitized solar cells.

A series of organic dyes based on quinoline as an electron-deficient π-linker, were designed and synthesized for dye sensitized solar cells (DSSC) application. These push-pull conjugated dyes, sharing same anchoring group with distinctive electron-rich donating groups such as N,N-diethyl (DEA-Q), 3,6-dimethoxy carbazole (CBZ-Q), bis(4-butoxyphenyl)amine (BPA-Q), were synthesized by Riley oxidation of CH followed by Knoevenagel condensation of the corresponding aldehyde precursors 2a-c with cyanoacrylic acid. The optical, electrochemical, theoretical calculation and photovoltaic properties with these three dyes were systematically investigated.

Investigating Substrate Scope and Enantioselectivity of a Defluorinase by a Stereochemical Probe.

The possibility of a double Walden inversion mechanism of the fluoracetate dehalogenase FAcD (RPA1163) has been studied by subjecting rac-2-fluoro-2-phenyl acetic acid to the defluorination process. This stereochemical probe led to inversion of configuration in a kinetic resolution with an extremely high selectivity factor (E > 500), showing that the classical mechanism involving S2 reaction by Asp110 pertains. The high preference for the (S)-substrate is of synthetic value.

Biocatalysts for the pharmaceutical industry created by structure-guided directed evolution of stereoselective enzymes.

Enzymes have been used for a long time as catalysts in the asymmetric synthesis of chiral intermediates needed in the production of therapeutic drugs. However, this alternative to man-made catalysts has suffered traditionally from distinct limitations, namely the often observed wrong or insufficient enantio- and/or regioselectivity, low activity, narrow substrate range, and insufficient thermostability. With the advent of directed evolution, these problems can be generally solved.