The role of the cGAS-STING signaling pathway in viral infections, inflammatory and autoimmune diseases.

Pattern recognition receptors are an essential part of the immune system, which detect pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs) and help shape both innate and adaptive immune responses. When dsDNA is present, cyclic GMP-AMP Synthase (cGAS) produces a second messenger called cyclic GMP-AMP (cGAMP), which then triggers an adaptor protein called STING, and eventually activates the expression of type I interferon (IFN) and pro-inflammatory cytokines in immune cells. The cGAS-STING signaling pathway has been receiving a lot of attention lately as a key immune-surveillance mediator. In this review, we summarize the present circumstances of the cGAS-STING signaling pathway in viral infections and inflammatory diseases, as well as autoimmune diseases. Modulation of the cGAS-STING signaling pathway provides potential strategies for treating viral infections, inflammatory diseases, and autoimmune diseases.

Activation of aminocyclopropanes via radical intermediates.

Aminocyclopropanes are versatile building blocks for accessing high value-added nitrogen-containing products. To control ring-opening promoted by ring strain, the Lewis acid activation of donor-acceptor substituted systems is now well established. Over the last decade, alternative approaches have emerged proceeding via the formation of radical intermediates, alleviating the need for double activation of the cyclopropanes. This tutorial review summarizes key concepts and recent progress in ring-opening transformations of aminocyclopropanes via radical intermediates, divided into formal cycloadditions and 1,3-difunctionalizations.

Diamine Synthesis via the Nitrogen-Directed Azidation of σ- and π-C-C Bonds.

Diamines are essential building blocks for the synthesis of agrochemicals, drugs, and organic materials, yet their synthesis remains challenging, as both nitrogens need to be differentiated and diverse substitution patterns (1,2, 1,3, or 1,4) are required. We report herein a new strategy giving access to 1,2, 1,3, and 1,4 amido azides as orthogonally protected diamines based on the nitrogen-directed diazidation of alkenes, cyclopropanes, and cyclobutanes. Commercially available copper thiophene-2-carboxylate (CuTc, 2 mol %) as catalyst promoted the diazidation of both π and σ C-C bonds within 10 min in the presence of readily available oxidants and trimethylsilyl azide. Selective substitution of the formed α-amino azide by carbon nucleophiles (electron-rich aromatic, malonate, organosilicon, organoboron, organozinc, and organomagnesium compounds) was then achieved in a one-pot fashion, leading to the formation of 1,2-, 1,3-, and 1,4-diamines with the amino groups protected orthogonally as an amide/carbamate and an azide.

Physiological and transcriptomic analyses reveal novel insights into the cultivar-specific response to alkaline stress in alfalfa (Medicago sativa L.).

Soil alkalization severely limits plant growth and development, however, the mechanisms of alkaline response in plants remain largely unknown. In this study, we performed physiological and transcriptomic analyses using two alfalfa cultivars (Medicago sativa L.) with different sensitivities to alkaline conditions. The chlorophyll content and shoot fresh mass drastically declined in the alkaline-sensitive cultivar Algonquin (AG) following alkaline treatment (0-25 mM Na2CO3 solution), while the alkaline-tolerant cultivar Gongnong NO.1 (GN) maintained relatively stable growth and chlorophyll content. Compared with AG, GN had higher contents of Ca2+ and Mg2+; the ratios of Ca2+ and Mg2+ to Na+, proline and soluble sugar, as well as higher enzyme activities of peroxidase (POD) and catalase (CAT) under the alkaline conditions. Furthermore, transcriptomic analysis identified three categories of alkaline-responsive differentially expressed genes (DEGs) between the two cultivars: 48 genes commonly induced in both the cultivars (CAR), 574 genes from the tolerant cultivar (TAR), and 493 genes from the sensitive cultivar (SAR). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses showed that CAR genes were mostly involved in phenylpropanoid biosynthesis, lipid metabolism, and DNA replication and repair; TAR genes were significantly enriched in metabolic pathways, such as biosynthesis of amino acids and secondary metabolites including flavonoids, and the MAPK signaling pathway; SAR genes were specifically enriched in vitamin B6 metabolism. Taken together, the results identified candidate pathways associated with genetic variation in response to alkaline stress, providing novel insights into the mechanisms underlying alkaline tolerance in alfalfa.

A novel specific cleavage of IκBα protein in acute myeloid leukemia cells involves protease PR3.

IκBα protein plays an important role in NFκB signaling pathway regulation. The dysfunction of IκBα is tightly related to various diseases, including cancers. However, the molecular mechanisms by which IκBα loses its normal functions are diverse and complex. Here, we reported a novel cleavage of IκBα protein occurred in AML cells. Compared with the full-length IκBα protein, the truncated IκBα fragment exhibited a dramatically weak binding ability to NFκB complex and showed a significant decreased inhibition on NFκB transactivation. Knockdown of PR3, a serine protease mainly expressed in myeloid cells, could inhibit such IκBα cleavage and enhance the sensitivities of AML cells to the differentiation inducers. In addition, we showed that the level of PR3 mRNA was relatively higher in newly diagnosed AML patients than in those patients with complete remission, suggesting that PR3 expression and its involvement in IκBα cleavage might be closely associated with AML. Our studies revealed for the first time a PR3-involved IκBα cleavage in AML cells, providing some new evidences for further understanding the mechanisms underlying the deregulation of NFκB pathway in AML. Finally, we also suggested a potential clinical application value of PR3 protein in the treatment and prognosis surveillance for leukemia.

Oxidative Fluorination of Cyclopropylamides through Organic Photoredox Catalysis.

We report an oxidative ring-opening strategy to transform cyclopropylamides and cyclobutylamides into fluorinated imines. The imines can be isolated in their more stable hemiaminal form, with the fluorine atom installed selectively at the γ or δ position. Both inexpensive benzophenone with UVA light or organic and inorganic dyes with blue light could be used as photoredox catalysts to promote this process. Various fluorinated amines were then obtained by nucleophilic attack on the hemiaminals in one pot, giving access to a broad range of useful building blocks for medicinal chemistry.

1,3-Difunctionalization of Aminocyclopropanes via Dielectrophilic Intermediates.

We report an oxidative ring-opening strategy to transform acyl, sulfonyl or carbamate protected aminocyclopropanes into 1,3-dielectrophilic carbon intermediates bearing a halide atom (Br, I) and a N,O-acetal. Replacing the alkoxy group of the N,O-acetal can be achieved under acidic conditions through an elimination-addition pathway, while substitution of the halides by nucleophiles can be done under basic conditions through a SN 2 pathway, generating a wide range of 1,3-difunctionalized propylamines. A proof of concept for asymmetric induction was realized using a chiral phosphoric acid (CPA) as catalyst, highlighting the potential of the method in enantioselective synthesis of important building blocks.

Phylogenomics resolves the deep phylogeny of seed plants and indicates partial convergent or homoplastic evolution between Gnetales and angiosperms.

After decades of molecular phylogenetic studies, the deep phylogeny of gymnosperms has not been resolved, and the phylogenetic placement of Gnetales remains one of the most controversial issues in seed plant evolution. To resolve the deep phylogeny of seed plants and to address the sources of phylogenetic conflict, we conducted a phylotranscriptomic study with a sampling of all 13 families of gymnosperms and main lineages of angiosperms. Multiple datasets containing up to 1 296 042 sites across 1308 loci were analysed, using concatenation and coalescence approaches. Our study generated a consistent and well-resolved phylogeny of seed plants, which places Gnetales as sister to Pinaceae and thus supports the Gnepine hypothesis. Cycads plus Ginkgo is sister to the remaining gymnosperms. We also found that Gnetales and angiosperms have similar molecular evolutionary rates, which are much higher than those of other gymnosperms. This implies that Gnetales and angiosperms might have experienced similar selective pressures in evolutionary histories. Convergent molecular evolution or homoplasy is partially responsible for the phylogenetic conflicts in seed plants. Our study provides a robustly reconstructed backbone phylogeny that is important for future molecular and morphological studies of seed plants, in particular gymnosperms, in the light of evolution.

Dithiocarbamates: Efficient metallo-ß-lactamase inhibitors with good antibacterial activity when combined with meropenem.

The activity of ß-lactam antibiotics is compromised by metallo-ß-lactamases (MBLs). Herein, a series of dithiocarbamate derivatives were designed and synthesized. Their antibacterial activities were tested in combination with meropenem (MEM) against several MBL (NDM and IMP type)-producing clinical isolates. Clinical isolates harboring NDM-1 and IMP-4 became susceptible to MEM when it was combined with dithiocarbamate compounds 4a, 4b or 4f synthesized in this work. Compounds 4a and 4b increased the effectiveness of MEM by up to 2560 times against strains. In vitro bactericidal dynamics tests showed that bacteria died within 24 h when they were treated with compound 4f + MEM. Compounds 4a, 4b and 4f were non-hemolytic and exhibited low toxicity toward HeLa cells in vitro. These data show that compounds containing dithiocarbamate functional group may be helpful in the development of MBL inhibitors.

NOTA analogue: A first dithiocarbamate inhibitor of metallo-ß-lactamases.

The emergence of antibiotic drug (like carbapenem) resistance is being a global crisis. Among those resistance factors of the ß-lactam antibiotics, the metallo-ß-lactamases (MBLs) is one of the most important reasons. In this paper, a series of cyclic dithiocarbamate compounds were synthesized and their inhibition activities against MBLs were initially tested combined with meropenem (MEM) by in vitro antibacterial efficacy tests. Sodium 1,4,7-triazonane-1,4,7-tris(carboxylodithioate) (compound 5) was identified as the most active molecule to restore the activity of MEM. Further anti-bacterial effectiveness assessment, compound 5 restored the activity of MEM against Escherichia coli, Citrobacter freundii, Proteus mirabilis and Klebsiella pneumonia, which carried resistance genes of blaNDM-1. The compound 5 was non-hemolytic, even at a concentration of 1000 µg/mL. This compound was low toxic toward mammalian cells, which was confirmed by fluorescence microscopy image and the inhibition rate of HeLa cells. The Ki value of compounds 5 against NDM-1 MBL was 5.63 ±â€¯1.27 µM. Zinc ion sensitivity experiments showed that the inhibitory effect of compound 5 as a MBLs inhibitor was influenced by zinc ion. The results of the bactericidal kinetics displayed that compound 5 as an adjuvant assisted MEM to kill all bacteria. These data validated that this NOTA dithiocarbamate analogue is a good inhibitor of MBLs.

Lewis Acid Catalyzed Enantioselective Desymmetrization of Donor-Acceptor meso-Diaminocyclopropanes.

The first Lewis acid catalyzed enantioselective ring-opening desymmetrization of a donor-acceptor meso-diaminocyclopropane is reported. The copper(II)-catalyzed Friedel-Crafts alkylation of indoles and one pyrrole with an unprecedented meso-diaminocyclopropane delivered enantioenriched, diastereomerically pure urea products, which are structurally related to natural and synthetic bioactive compounds. The development of a new ligand through the investigation of an underexplored subclass of bis(oxazoline) ligands was essential for achieving high enantioselectivities.

[Dynamic Visible Microcirculation and Activating Blood Removing Stasis Research].

The technology of dynamic visualization microcirculation is to observe changes of mi- crocirculation by using visualization technology, combined with fluorescence labeling, high-speed video, electronic microscopy and other methods, converting rest images into dynamic visual graphics. In the past ten years, domestic researchers used this technology, and carried out researches on the heart, piamater/mesenteric microcirculation, dynamically observed effects of activating blood removing stasis (ABRS) research monomer, single herb and compound on arteriole/venula diameter, and the velocity of red blood cell, white blood cell adhesion, platelet aggregation, microvascular permeability, superoxide production, and plasma albumin leakage, etc. Microcirculation detection technologies were further opti- mized. Exerting direct advantages of dynamic visualization microcirculation, systematically evaluating ac- tion mechanism of Chinese herbs (multi-sites and multi-targets) , and interaction mechonism between Chinese herbs and Western drugs are important directions for future researches on microcirculation.

Copper-Mediated Late-Stage Functionalization of Heterocycle-Containing Molecules.

One long-standing issue in directed C-H functionalization is that either nitrogen or sulfur atoms present in heterocyclic substrates may bind preferentially to a transition-metal catalyst rather than to the desired directing group. This competitive binding has largely hindered the application of C-H functionalization in late-stage heterocycle drug discovery. Reported here is the use of an oxazoline-based directing group capable of overriding the poisoning effect of a wide range of heterocycle substrates. The potential use of this directing group in pharmaceutical drug discovery is illustrated by diversification of Telmisartan (an antagonist for the angiotensin II receptor) through copper-mediated C-H amination, hydroxylation, thiolation, arylation, and trifluoromethylation.

A high frequency of allopolyploid speciation in the gymnospermous genus Ephedra and its possible association with some biological and ecological features.

The origin and evolution of polyploids have been studied extensively in angiosperms and ferns but very rarely in gymnosperms. With the exception of three species of conifers, all natural polyploid species of gymnosperms belong to Ephedra, in which more than half of the species show polyploid cytotypes. Here, we investigated the origin and evolution of polyploids of Ephedra distributed in the Qinghai-Tibetan Plateau (QTP) and neighbouring areas. Flow cytometry (FCM) was used to measure the ploidy levels of the sampled species that are represented by multiple individuals from different populations, and then, two single-copy nuclear genes (LFY and DDB2) and two chloroplast DNA fragments were used to unravel the possible origins and maternal donors of the polyploids. The results indicate that the studied polyploid species are allopolyploids, and suggest that allotetraploidy is a dominant mode of speciation in Ephedra. The high percentage of polyploids in the genus could be related to some of its biological attributes such as vegetative propagation, a relatively high rate of unreduced gamete formation, and a small genome size relative to most other gymnosperms. Significant ecological divergences between allotetraploids and their putative progenitors were detected by PCAs and anova and Tukey's tests, with the exception of E. saxatilis. The overlap of geographical distributions and ecological niches of some diploid species could have provided opportunities for interspecific hybridization and allopolyploid speciation.

Pretreatment with a combination of ligustrazine and berberine improves cardiac function in rats with coronary microembolization.

AIM: We have shown that a combination of ligustrazine and berberine produces more effective inhibition on platelet activation and inflammatory reactions in rat acute myocardial infarction compared with either agent alone. In this study we evaluated the beneficial effects of a combination of ligustrazine and berberine in a rat model of coronary microembolization (CME). METHODS: SD rats were treated with ligustrazine, berberine, ligustrazine+berberine, or clopidogrel for 2 weeks. When the treatment completed, CME was induced by injection of sodium laurate into the left ventricular, while obstructing the ascending aorta. All rats were intubated for hemodynamic measurements. Blood samples were collected for biochemical analyses, flow cytometry, and ELISAs. Heart tissues were isolated for histopathology and subsequent protein analyses. RESULTS: Pretreatment with the combination of ligustrazine (27 mg·kg(-1)·d(-1)) and berberine (90 mg·kg(-1)·d(-1)) significantly improved cardiac function, and decreased myocardial necrosis, inflammatory cell infiltration, microthrombosis and serum CK-MB levels in CME rats. In addition, this combination significantly decreased plasma ET-1 levels and von Willebrand factor, inhibited ADP-induced platelet activation, and reduced TNFα, IL-1ß, ICAM-1 and RANTES levels in serum and heart tissues. The protective effects of this combination were more prominent than those of ligustrazine or berberine alone, but comparable to those of a positive control clopidogrel (6.75 mg·kg(-1)·d(-1)). CONCLUSION: The combination of ligustrazine and berberine significantly improved cardiac function in rat CME model via a mechanism involving antiplatelet and anti-inflammatory effects.

Cloning and promoter activity analyses of the promoter of 2'-deoxymugineic acid (DMA) secretion channel gene YS3 in maize.

Iron (Fe) deficiency is a world-wide serious agricultural problem. Maize secretes 2'-deoxymugineic acid (DMA) to uptake and utilize Fe from the soil. In order to explore the gene expression patterns of the DMA secretion channel gene YS3, we cloned the 2813 bp YS3 promoter, and constructed the plant expression vector pCAMBIA-YS3GUS. The promoter contains a lot of TATA-boxes and CAAT-boxes, and cis-acting regulatory elements such as the light responsive elements and the hormone responsive elements. Arabidopsis was transformed via Agrobacterium tumefacients-mediated procedures to obtain the pYS3::GUS transgenic plants, which were confirmed by GUS staining. Then, the stained tissue was observed using paraffin section methods and the YS3 promoter activity was also analyzed. We found that the promoter could drive GUS gene expression specifically in the root epidermal cells. Mechanical damage could activate the promoter, and drive the GUS gene expression adjacent to the damage sites. Our results provide a molecular basis to understand the DMA secretion process in maize.

[Chinese Herbal Compounds for Supplementing Qi and Activating Blood Circulation Combined with Dual Antiplatelet Drugs Alleviated Human Umbilical Vein Endothelial Cell Injury and Platelet Adhe- sion via Up-regulation of P13K/Akt Pathway].

OBJECTIVE: To observe the effect and underlying mechanism of Chinese herbal com- pound (CHC) for supplementing qi and activating blood circulation (SQABC) combined with dual antiplatelet drugs (DA) on oxidized low density lipoprotein (ox-LDL) induced human umbilical vein endothelial cell (HUVEC) injury and platelet adhesion evoked by injured endothelial cells (ECs) based on P13K/Akt signaling pathway. METHODS: HUVECs were randomly divided into 5 groups, i.e., the blank control group, the model group (80 mg/L ox-LDL) , the DA group (15 µg/mL aspirin +10 µg/ mL clopidogrel +80 mg/L ox-LDL) , the Panax Quinquefolium saponins ( PQS, 160 µLg/mL) + Panax Notoginseng saponins (PNS, 160 µg/mL) +DA group, the LY294002 (30 µg/mL) + PQS + PNS + DA group. HUVEC apoptosis rate and platelet adhesion to HUVECs were detected by flow cytometry. Concentration of lactate dehydrogenase ( LDH) in HUVEC supernatant was detected by biochemical assay. Concentration of intercellular adhesion molecular ([CAM) was detected by radioimmunoassay. Protein expressions of p-P13K and p-Akt in HU- VECs were detected by Western blot. RESULTS: Compared with the blank control group, the apoptosis rate of HUVECs, mean fluorescence indicator ( MFI) , concentrations of both LDH and ICAM increased (P <0. 05) , and p-Akt protein expression decreased (P <0. 05) in the model group. Compared with the model group, the apoptosis rate of HUVECs and LDH concentration increased (P <0. 05), concentrations of MFI and ICAM obviously decreased (P <0. 05) in the DA group. The apoptosis rate, MFI, concentrations of both LDH and ICAM all decreased in the PQS + PNS + DA group (P <0. 05). p-Akt protein. expres- sion in HUVECs obviously increased in the PQS + PNS + DA group (P <0. 05). Compared with the DA group, HUVEC apoptosis rate, MFI, concentrations of both LDH and ICAM in supernatant obviously decreased, p-Akt expression in HUVECs increased in the PQS + PNS + DA group (all P <0. 05). p-Akt protein expression in HUVECs was inhibited after adding specific P13K inhibitor LY294002. Protection men- tioned above all disappeared in the PQS + PNS + DA group (P <0. 05). CONCLUSION: CHC for SQABC combined with DA could alleviate ox-LDL induced apoptosis of endothelial cells and reduce injured ECs e- voked platelet adhesion via up-regulation of P13K/Akt pathway in ECs.

Small longitudinal S incision and page turning style of annular ligament partial resection to treat stenosing tenosynovitis of thumb flexor tendon.

BACKGROUND: To present the treatment outcome for patients with stenosing tenosynovitis of thumb flexor tendon treated with a small S incision and page turning style of annular ligament partial resection. MATERIAL AND METHODS: During a 2-year period between August 2011 and July 2013, 12 consecutive patients (mean age, 45.8 years) with stenosing tenosynovitis of the thumb flexor tendon were prospectively enrolled into this study. All 12 patients underwent longitudinal S skin incision to expose annular ligament and thumb flexor tendon, and with page turning style of annular ligament partial resection to finish the operation. The average range of motion of metacarpophalangeal thumb joint, Quick disability of arm, shoulder, and hand and Short Musculoskeletal Function Assessment Dysfunction score of arm and hand were primary outcome measures. RESULTS: There were 9 cases of stiff metacarpophalangeal joint of thumb and 3 cases of snapping thumb for stenosing tenosynovitis. At 1-year follow-up, all stenosing tenosynovitis had healed by an average of 4 weeks. The average range of motion of the metacarpophalangeal joint was 37.1° (range, 34-40°). No patients had recurrence, cicatricial contraction, or postoperative infection. The average disability of arm, shoulder, and hand was 0.3 out of 100 (range, 0-1.67), and average Short Musculoskeletal Functional Assessment Dysfunction score of arm and hand was 6.9 out of 40 (range, 0-15.6). All 12 patients stated that they were highly satisfied. CONCLUSIONS: Small S incision and page turning style of annular ligament partial resection for stenosing tenosynovitis of thumb flexor tendon is a safe, simple, and reliable alternative treatment with minimal soft-tissue irritation, good functional results and recovery can be expected.

Crystal structure of (E)-2-(2-{5-[(2-acet-oxy-eth-yl)(meth-yl)amino]-thio-phen-2-yl}vin-yl)-3-methyl-benzo-thia-zolium iodide monohydrate.

In the cation of the title hydrated salt, C19H21N2O2S2 (+)·I(-)·H2O, the benzo-thia-zolium ring system is approximately planar [maximum deviation = 0.0251 (15) Å], and it makes a small dihedral angle of 1.16 (18)° with the plane of the thio-phene ring. In the crystal, the cations, anions and crystalline water mol-ecules are linked by classical O-H⋯O, O-H⋯I and weak C-H⋯O hydrogn bonds, forming a three-dimensional supra-molecular network. π-π stacking is observed between parallel thia-zole rings of adjacent cations [centroid-centroid distance = 3.5945 (16) Å].

Application and subgroup analysis of competing risks model based on different lymph node staging systems in differentiated thyroid cancer.

Differentiated thyroid cancer (DTC) is the most common endocrine malignancy, with a rising incidence worldwide. Accurate prognostic models are essential for effective patient management. This study evaluates the prognostic value of various lymph node staging systems in DTC using a competing risks model. We used SEER database records (1998-2016) of 16,527 DTC patients, analyzing N stage, positive lymph node numbers (PLNNs), metastatic lymph node ratio (MLNR), log odds of positive lymph nodes (LODDS), and log odds of the negative lymph node (NLN)/T stage ratio (LONT). Univariate and multivariate analyses in a competing risks model were performed, along with subgroup analyses based on demographic and clinical characteristics. In this study of 16,527 patients with DTC, different lymph node staging systems showed different prognostic correlations in univariate and multivariate analyses. In particular, PLNNs showed significant prognostic correlations in several subgroups. Additionally, PLNNs were more suitable as a lymph node staging system for DTC than LODDS and MLNR in N1 stage subgroups, with an optimal cut-off of 13. Receiver operating characteristic curves, calibration curves and nomograms improved the clinical utility of the prognostic model based on PLNNs. Using competing risks model and subgroup analyses, we found that PLNNs had the best prognostic discriminatory efficacy for patients with DTC, especially those with N1 stage disease, and had an optimal cut-off value of 13.