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. From these data we identified 393 viral species associated with mosquitoes, including 7 (putative) species of arthropod-borne viruses (that is, arboviruses). We identified potential mosquito species and geographic hotspots of viral diversity and arbovirus occurrence, and demonstrated that the composition of individual mosquito viromes was strongly associated with host phylogeny. Our data revealed a large number of viruses shared among mosquito species or genera, enhancing our understanding of the host specificity of insect-associated viruses. We also detected multiple virus species that were widespread throughout the country, perhaps reflecting long-distance mosquito dispersal. Together, these results greatly expand the known mosquito virome, linked viral diversity at the scale of individual insects to that at a country-wide scale, and offered unique insights into the biogeography and diversity of viruses in insect vectors.

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. From these data we identified 393 core viral species associated with mosquitos, including seven (putative) arbovirus species. We identified potential species and geographic hotspots of viral richness and arbovirus occurrence, and demonstrated that host phylogeny had a strong impact on the composition of individual mosquito viromes. Our data revealed a large number of viruses shared among mosquito species or genera, expanding our knowledge of host specificity of insect-associated viruses. We also detected multiple virus species that were widespread throughout the country, possibly facilitated by long-distance mosquito migrations. Together, our results greatly expand the known mosquito virome, linked the viral diversity at the scale of individual insects to that at a country-wide scale, and offered unique insights into the ecology of viruses of insect vectors.

[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 30.69 Gb nucleotide bases and 89 564 transcripts were obtained after redundancy removal. These transcripts had a mean length of 2 060 bp and an N50 value of 3 156 bp. Based on the full-length transcriptome sequencing data, 64 candidate proteins were selected from the WRKY transcription factor family, with the protein size of 92-1 027 aa, the relative molecular mass of 10 377.85-115 779.48 kDa, and the isoelectric point of 4.49-9.84. These WRKY family members were mostly located in the nucleus and belonged to the hydrophobic proteins. According to the phylogenetic analysis of WRKY family in P. cyrtonema and Arabidopsis thaliana, all WRKY family members were clustered into seven subfamilies and WRKY proteins from P. cyrtonema were distributed in different numbers in these seven subgroups. Expression pattern analysis confirmed that 40 WRKY family members had distinct expression patterns in the rhizomes of 1-and 3-year-old P. cyrtonema. Except for PcWRKY39, the expression of 39 WRKY family members was down-regulated in 3-year-old samples. In conclusion, this study provides abundant reference data for genetic research on P. cyrtonema and lays a foundation for the in-depth investigation of the biological functions of the WRKY family.

[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. It is different from not only the magic bullet theory of single component action but also the connotation of modern multi-target drugs. The core of Yiyin decoction theory can be summarized as compound compatibility, multiple effects, and moderate regulation. Compound compatibility refers to that the formulation of Chinese medicinal prescriptions involves the complex synergy and interactions between sovereign, minister, assistant, and guide medicinal materials. Multiple effects mean that the prescriptions employ a variety of mechanisms to exert comprehensive pharmacological effects of nonlinear feedback. Moderate regulation reflects that the prescriptions can accurately regulate the multiple points of the disease biological network as a whole. To solve the mystery of Yiyin decoction theory, we should not only simply study the known active substances(components) and their independent target effects in the mixture, but also mine the "dark matter" and "dark effect" of Chinese medicinal prescriptions. That is, we should learn the neglected atypical pharmacological effects of Chinese medicinal prescriptions and the multi-point nesting mechanism that plays a precise regulatory function in the body. Yiyin decoction theory focuses on the overall pharmacological effect to reflect the comprehensive clinical value of Chinese medicinal prescriptions, which is of great significance for the development of a new model for the evaluation and application of new Chinese medicinal prescriptions in line with the theory of traditional Chinese medicine.

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. Increasing evidence indicates that a prior oxidation of quercetin to generate an array of chemical diverse products with redox-active/electrophilic moieties is emerging as a new linkage to its versatile actions. The present review aims to provide a comprehensive overview of the oxidative conversion of quercetin by systematically analyzing the current quercetin-related knowledge, with a particular focus on the complete spectrum of metabolite products, the enzymes involved in the catabolism and the underlying molecular mechanisms. Herein we review and compare the oxidation pathways, protein structures and catalytic patterns of the related metalloenzymes (phenol oxidases, heme enzymes and specially quercetinases), aiming for a deeper mechanistic understanding of the unusual biotransformation behaviors of quercetin and its seemingly controversial biological functions.

Acute pancreatitis as a rare complication of gastrointestinal endoscopy: A case report.

BACKGROUND: Acute pancreatitis is an uncommon complication of gastrointestinal endoscopy, especially if the patient has none of the common risk factors associated with pancreatitis; such as alcoholism, gallstones, hypertriglyceridemia, hypercalcemia or the use of certain drugs. CASE SUMMARY: A 56-year-old female patient developed abdominal pain immediately after the completion of an upper gastrointestinal endoscopy. The pain was predominantly in the upper and middle abdomen and was persistent and severe. The patient was diagnosed with acute pancreatitis. Treatment included complete fasting, octreotide injection prepared in a prefilled syringe to inhibit pancreatic enzymes secretion, ulinastatin injection to inhibit pancreatic enzymes activity, esomeprazole for gastric acid suppression, fluid replacement and nutritional support. Over the next 3 d, the patient's symptoms improved. The patient remained hemodynamically stable throughout hospitalization and was discharged home in a clinically stable state. CONCLUSION: Pancreatitis should be considered in the differential diagnosis of abdominal pain after upper and lower gastrointestinal endoscopy.

Cascade of C(sp2)-H Addition to Carbonyl and C(sp2)-CN/C(sp2)-H Coupling Enabled by Brønsted Acid: Construction of Benzo[a]carbazole Frameworks.

Herein, we report an unprecedented cascade reaction of C(sp2)-H addition to carbonyl and the C(sp2)-CN/C(sp2)-H coupling of 2-(2-oxo-2-arylethyl)benzonitriles with indoles enabled by commercially available TsOH·H2O. The protocol represents the first metal-free C(sp2)-CN/C(sp2)-H coupling, affording a new route for the synthesis of various benzo[a]carbazole derivatives with a broad substrate scope, high yields, and simple conditions.

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. Here, we systematically investigated the catalytic actions of FAcD toward its natural substrate fluoroacetate using molecular dynamics simulations and quantum mechanism/molecular mechanism calculations. We propose that the enzymatic transformation involves four elementary steps, (I) C-F bond activation, (II) nucleophilic attack, (III) C-O bond cleavage, and (IV) proton transfer. Our results show that nucleophilic attack is the rate-determining step. However, for difluoroacetate and trifluoroacetate, C-F bond activation, instead of nucleophilic attack, becomes the rate-determining step. We show that FAcD, originally recognized as α-fluorocarboxylic acid degradation enzyme, can catalyze the defluorination of difluoroacetate to glyoxylate, which is captured by our high-resolution mass spectrometry experiments. In addition, we employed amino acid electrostatic analysis method to screen potential mutation hotspots for tuning FAcD's electrostatic environment to favor substrate conversion. The comprehensive understanding of catalytic mechanism will inform a rational enzyme engineering strategy to degrade fluorochemicals for benefits of environmental sustainability.

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. Here, we summarize progress made in the past 10 years in stereoselective C-C bond formation enabled by two classic types of enzyme, aldolases and hydroxynitrile lyases. The information in this review will enable the development of new routes to the stereoselective construction of C-C bonds.

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. Laboratory examination revealed a hemoglobin level of 83 g/L, and a platelet count of 397 × 109/L. The appearance of gastric and esophageal varices with red colored signs as displayed by an urgent endoscopy was followed by endoscopic variceal ligation and endoscopic tissue adhesive. Abdominal computed tomography revealed cirrhosis, marked splenomegaly, portal vein thrombosis and portal hypertension. In addition, bone marrow biopsy and evidence of mutated Janus kinase 2, substantiated the onset of ET. The patient was asymptomatic with regular routine blood testing during the 6-mo follow-up period. Therefore, in this case, gastroesophageal varices were induced by ET. CONCLUSION: MPN should be given considerable attention when performing differential diagnoses in patients with gastroesophageal varices. An integrated approach such as laboratory tests, radiological examination, and pathological biopsy, should be included to allow optimal decisions and management.

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. Here, we report the potential metabolic vulnerabilities of A549/DDP (drug-resistant human lung adenocarcinoma cell lines) cells, which were more easily killed by the iron chelator deferoxamine (DFO) during glutamine deprivation than their parental cisplatin-sensitive A549 cells. We demonstrate that phenotype resistance to cisplatin is accompanied by adaptive responses during glutamine deprivation partly via higher levels of autophagic activity and apoptosis resistance characteristics. Moreover, this adaptation could be explained by sustained glucose instead of glutamine-dominant complex II-dependent oxidative phosphorylation (OXPHOS). Further investigation revealed that cisplatin-resistant cells sustain OXPHOS partly via iron metabolism reprogramming during glutamine deprivation. This reprogramming might be responsible for mitochondrial iron-sulfur [Fe-S] cluster biogenesis, which has become an "Achilles' heel," rendering cancer cells vulnerable to DFO-induced autophagic cell death and apoptosis through c-Jun N-terminal kinase (JNK) signaling. Finally, in vivo studies using xenograft mouse models also confirmed the growth-slowing effect of DFO. In summary, we have elucidated the adaptive responses of cisplatin-resistant NSCLC cells, which balanced stability and plasticity to overcome metabolic reprogramming and permitted them to survive under stress induced by chemotherapy or glutamine starvation. In addition, for the first time, we show that suppressing the growth of cisplatin-resistant NSCLC cells via iron chelator-induced autophagic cell death and apoptosis was possible with DFO treatment. These findings provide a solid basis for targeting mitochondria iron metabolism in cisplatin-resistant NSCLC for therapeutic purposes, and it is plausible to consider that DFO facilitates in the improvement of treatment responses in cisplatin-resistant NSCLC patients.

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)-H2O2 (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. 1-Thiochromanone and 1-tetralone were used as the isosteric substrates because, unlike previous studies involving fully flexible compounds such as thia-fatty acids and fatty acids, respectively, these compounds are rigid and cannot occur in a multitude of different conformations and binding modes in the large P450-BM3 binding pocket. The experimental results comprising activity and regio- and enantioselectivity, flanked by molecular dynamics computations within a time scale of 300 ns and QM/MM calculations of transition-state energies, unequivocally show that heme-Fe═O (Cpd I) is the common catalytically active intermediate in both sulfoxidation and oxidative hydroxylation.

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. The experimentally determined kcat and kM for defluorination of 2-fluoropropionic acid are 330 ±â€¯60 min-1 and 6.12 ±â€¯0.13 mM. The in silico results demonstrated positive/negative correlations between activation barriers and structural parameters (e.g. distance and angle) under different enzymatic conformations. We also screened computationally and tested in vitro (enzyme assay and kinetic study) the catalytic proficiency of FAcD toward polyfluoropropionic acids and perfluoropropionic acids which are known to be challenging for enzymatic degradation. The results revealed potential degradation activity of FAcD enzyme toward 2,3,3,3-tetrafluoropropionic acids. Our work will initiate the development of a new "integrated approach" for enzyme engineering to degrade environmentally persistent fluorocarboxylic acids.

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 (OleTJE) not only function as catalysts for the crucial initial reactions, they also ensure an internal in situ H2O2 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. METHODS: The FGF-2 gene overexpressed lentivirus-transfected rBMSCs with xenogeneic antigen-extracted cancellous bone (XACB) to construct tissue engineered bone, and the model of early avascular necrosis of the femoral head was established by lipopolysaccharide (LPS) combined with hormone. The models were randomly divided into five groups: A (control), B (XACB), C (XACB+rBMSCs), D (XACB+rBMSCs+Lv-GFP), and E (XACB+rBMSCs+Lv-FGF-2/GFP) groups. The therapeutic effect of the tissue engineered bone for the avascular necrosis of the femoral head was evaluated by gross anatomy, X-ray examination, immunohistochemistry and H&E staining. RESULTS: The FGF-2 gene was transfected into rBMSCs (Multiplicity of infection [MOI] = 100) by lentivirus, and its efficiency was above 95%. The rBMSCs were successfully transfected overexpressing FGF-2 by qPCR and western blot. After tissue engineering bone implantation, X-ray examination and gross specimen observation revealed that the repair area in the E group was > 80% at six weeks, the defect was completely repaired at 12 weeks, and osteogenesis was stronger, when compared with the other groups. For the X-ray score, vascular area density and new bone formation area were higher, when compared with the other groups, and the difference was statistically significant (P< 0.05). CONCLUSION: FGF-2 gene overexpression lentivirus transfection BMSCs combined with XACB to construct tissue engineered bone can effectively promote vascular regeneration, and improve the repair effect of avascular necrosis of the femoral head.

Spinal glucocorticoid receptor­regulated chronic morphine tolerance may be through extracellular signal­regulated 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 mitogen­activated protein kinase [MAPK; phosphorylated extracellular signal­regulated kinase (ERK)] is regulated through the spinal GRs, following chronic treatment with morphine. In the first experiment, the experimental rats were randomly divided into four groups: Control, morphine, morphine+GR antagonist mifepristone (RU38486) and morphine+GR agonist dexamethasone (Dex). Each group was treated with continuous intrathecal (IT) injection of the drugs for 6 days. The expression of GRs and MAPK 3/1 (p­ERK 1/2) in the spinal dorsal horn was detected by western blot analysis and immunofluorescence staining. In the second experiment, the MAPK inhibitor PD98059 was added and the rats were randomly divided into four groups: Control, morphine, PD98059+morphine and PD98059+morphine+Dex. The continuous IT injection lasted for 7 days in each group. For all experiments, the tail flick test was conducted 30 min following administration every day to assess the thermal hyperalgesia of the rats. The experimental results demonstrated that there was a co­existence of GRs and p­ERK 1/2 in the spinal cord dorsal horn by double immunofluorescence staining. The GR antagonist RU38486 attenuated the morphine analgesia tolerance by inhibiting the expression of GR and increasing the expression of p­ERK. The MAPK inhibitor PD98059 increased the effect of morphine tolerance and prolonged the duration of morphine tolerance. The present results suggest that spinal GRs may serve an important role in the development of morphine tolerance through the ERK signaling pathway.

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. The challenge is to develop and apply the most efficient mutagenesis methods which lead to highest-quality mutant libraries requiring minimal screening. Structure-guided saturation mutagenesis and its iterative form have emerged as the method of choice for evolving stereo- and regioselective mutant enzymes needed in the asymmetric synthesis of chiral intermediates. The number of (industrial) applications in the preparation of chiral pharmaceuticals is rapidly increasing. This review features and analyzes typical case studies.

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 CH3 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. Compared to DEA-Q and CBZ-Q, BPA-Q possesses better light harvesting properties with regard to extended conjugate length, red-shifted intramolecular charge transfer band absorption and broaden light-responsive IPCE spectrum, resulting in a greater short circuit photocurrent density output. BPA-Q also has improved open-circuit voltage due to the apparent large charge recombination resistance. Consequently, assembled with iodine redox electrolytes, the device with BPA-Q achieved the best overall conversion efficiency value of 3.07% among three dyes under AM 1.5G standard conditions. This present investigation demonstrates the importance of various N-substituent chromophores in the prevalent D-π-A type organic sensitizers for tuning the photovoltaic performance of their DSSCs.