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This paper reports two new visible-light-promoted radical reactions of α-azido amides. By catalysis of [Ir(ppy)2(dtbbpy)]PF6 with i-Pr2NEt as the reducing agent, N-aryl α-azido tertiary amides were first converted to the corresponding aminyl radicals through reduction of the azido group; the aminyl radicals then underwent N-to-N aryl migration to give α-anilinyl-functionalized amides. α-Azido secondary amides, on the other hand, reacted with the solvent ethanol and i-Pr2NEt to afford the imidazolinone products.

A novel distal radical rearrangement of alkoxyphosphine is developed for the first time and applied to the regioselective radical fluoroalkylphosphorylation of unactivated olefins. By employing a one-pot two-step reaction of (bis)homoallylic alcohols, organophosphine chlorides, and fluoroalkyl iodides under CFL (compact fluorescence light) irradiation, a series of fluoroalkylphosphorylated alkyl iodides and alcohols are easily synthesized by regiospecific installing a phosphonyl onto the inner carbon of terminal olefins and further iodination/hydroxylation. Mechanism studies reveal that the migration undergoes a distinctive radical cyclization/β-scission on the lone electron pair of phosphorus, resulting in C-P bond formation and C-O bond cleavage.

This work represents the first [4+2] annulation of hydroxamic acids with olefins for the synthesis of benzo[c][1,2]oxazines scaffold via anode-selective electrochemical oxidation. This protocol features mild conditions, is oxidant free, shows high regioselectivity and stereoselectivity, broad substrate scope of both alkenes and hydroxamic acids, and is compatible with terpenes, peptides, and steroids. Significantly, the dioxygenation of olefins employing hydroxamic acid is also successfully achieved by switching the anode material under the same reaction conditions. The study not only reveals a new reactivity of hydroxamic acids and its first application in electrosynthesis but also provides a successful example of anode material-tuned product selectivity.

A regioselective radical fluoroalkylphosphorylation of unactivated alkenes has been developed by a one-pot twosteps reaction of (bis)homoallylic alcohols, organophosphine chlorides (R2PCl), and fluoroalkyl iodides (RFI) under visible light irradiation. This protocol employs the radical rearrangement of the in situ formed alkoxyphosphane for the first time to regiospecific installing a phosphonyl group onto the inner carbon of terminal olefins in alkene difunctionalization via C-P bond formation and C-O bond homolytic cleavage. Consequently, a series of high value-added fluoroalkylphosphorylated alkyl iodides and alcohols are easily and efficiently synthesized by subsequent iodination and hydroxylation of the generated carbon-centered radicals.

A novel radical 1,4/5-amino shift from the oxygen center of alkene-tethered diphenyl ketoxime ethers to the carbon center to achieve high value-added fluoroalkyl-containing primary β(γ)-amino-ketones is reported. Mechanism studies reveal that the migration is triggered by the alkene addition of fluoroalkyl radical derived from the electron donor-acceptor (EDA) complex of Togni's reagent II or fluoroalkyl iodides and quinuclidine, and involves a unique 5(6)-exo-trig cyclization of the carbon-centered radical onto the N-atom of ketoxime ethers followed by a cascade sequence of N-O bond cleavage and dehydrogenation. Notably, besides Togni's reagent II and fluoroalkyl iodides, this protocol is also compatible with other radical precursors to provide various functionalized primary aminoketones.

A decarboxylative borylation of aliphatic acids for the synthesis of a variety of alkylboronates has been developed by mixing m-chloroperoxybenzoic acid (mCPBA)-activated fatty acids with bis(catecholato)diboron in N,N-dimethylformamide (DMF) at room temperature. A radical chain process is involved in the reaction which initiates from the B–B bond homolysis followed by the radical transfer from the boron atom to the carbon atom with subsequent decarboxylation and borylation.

A 4-HO-TEMPO-catalyzed redox strategy for the synthesis of pyridines through the annulation of cyclopropanols and oxime acetates has been developed. This protocol features good functional group tol...

The complete mitogenome sequence of the slender shrew (Sorex gracillimus) was determined using long PCR. The genome was 17,002 bp in length and contained 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes, one origin of L strand replication, and one control region. The overall base composition of the heavy strand is A (32.5%), C (25.5%), T (28.5%), and G (13.5%). The base compositions present clearly the A–T skew, which is most obviously in the control region and protein-coding genes. The extended termination-associated sequence domain, the central conserved domain and the conserved sequence block domain are defined in the mitochondrial genome control region of the slender shrew. Mitochondrial genome analyses based on MP, ML, NJ, and Bayesian analyses yielded identical phylogenetic trees. The five Sorex species formed a monophyletic group with the high bootstrap value (100%) in all examinations.

Background. Activating transcription factor 6 (ATF6) and receptor-interacting protein 3 (RIP3) are important signaling proteins in endoplasmic reticulum (ER) stress and necroptosis, respectively. However, their regulatory relationship and clinical significance are unknown. We investigate the impact of ATF6 on RIP3 expression, and its role in hepatocyte necroptosis in an acute liver injury model. Methods. In vivo and in vitro experiments were carried out. LO2 cells were treated with thapsigargin (TG). In vivo, male BALB/c mice were treated with carbon tetrachloride (CCl4, 1 mL/kg) or tunicamycin (TM, 2 mg/kg). Then, the impact of ATF6 or RIP3 silencing on liver injury, hepatocyte necroptosis, and ER stress-related protein expression was examined. Results. TG induced ER stress and necroptosis and ATF6 and RIP3 expression in LO2 cells. The knockdown of ATF6 significantly decreased RIP3 expression ( p < 0.05 ) and increased ER stress and necroptosis. The downregulation of RIP3 significantly reduced necroptosis and ER stress ( p < 0.05 ). Similar results were observed in CCl4 or the TM-induced mouse model. The knockdown of ATF6 significantly decreased CCl4-induced RIP3 expression and increased liver injury, necroptosis, and ER stress in mice livers ( p < 0.05 ). In contrast, the downregulation of RIP3 significantly reduced liver injury, hepatocyte necroptosis, and ER stress. Conclusions. Hepatocyte ATF6 has multiple roles in acute liver injury. It reduces hepatocyte necroptosis via negative feedback regulation of ER stress. In addition, ATF6 can upregulate the expression of RIP3, which is not helpful to the recovery process. However, downregulating RIP3 reduces hepatocyte necroptosis by promoting the alleviation of ER stress. The findings suggest that RIP3 could be a plausible target for the treatment of liver injury.

In this study, experiments are performed to study the transmission of 15 keV C− ions through straight and tapered borosilicate glass capillaries. The tilt angle is varied from 0° to 0.8°. In a straight capillary, the transmitted ions produced only one spot on the detector, and its intensity declined with increasing tilt angle. In this case, almost 98% of the transmitted particles maintained their initial charge. However, in the tapered capillary, the transmitted particles formed a different pattern composed of a core and a halo. The negative ion fractions of the core and the halo were 97.5% and 42.5% at a 0° tilt angle, respectively. Therefore, the particles formed the halo by scattering after colliding with the inner surface of the capillary, and most of them were neutralized. As the tilt angle increased, the intensity and negative ion fraction of the transmitted particles declined, and the halo gradually became quite asymmetric. These results indicate that the scattering process plays a role in the transmission.

A total of 64 haplotypes were obtained from the complete Cytochrome b gene (Cyt b) of 77 Sorex isodon collected from three populations (Daxing'anling, Xiaoxing'anling, and Changbai Mountains) in Northeast China. The haplotype diversity was 0.9920 and the nucleotide diversity was 0.0105, indicating high genetic diversity. The genetic diversity of Changbai Mountains population was significantly higher than that of Daxing'anling and Xiaoxing'anling populations. The F-statistics, the number of migrants per generation and the genetic distance results showed that the genetic distances among the populations and among the sampling sites were generally consistent with geographical distance. Analysis of molecular variance showed that the differentiation among populations, among sampling sites, and within sampling site accounted for 33.4%, 10.2% and 56.4% of total variation, respectively. The analysis of population history showed that S. isodon in Northeast China experienced no population expansion. The reported complete sequence of Cyt b gene of S. isodon (GenBank) of Europe and other parts of Asia was downloaded to examine the genetic structure of S. isodon. The phylogenetic tree was divided into two large branches. One branch consisted mainly of Daxing'anling and Xiaoxing'anling samples. The other branch was departed into two sub-branches. Median-joining network analysis showed that there were three lineages: one lineage mainly consisted of haplotypes from Daxing'anling and Xiaoxing'anling, and also four haplotypes of Changbai Mountains, while the other lineage included a few haplotypes of three populations in Northeast China, and those from Baikal Lake, Russia and Finland. The last lineage was entirely composed of haplotypes from Changbai Mountains. The results of genetic diversity, phylogenetic tree and median-joining network all suggested that the Changbai Mountains was the refuge for S. isodon during last glacial.对中国东北地区3个种群(大兴安岭、小兴安岭和长白山山脉)的远东鼩鼱(77个样本)Cyt

Giant cell tumors of bone (GCTBs) exhibit high recurrence and aggressive bone lytic behavior; but, the mechanism of GCTB progression is largely unknown. In GCTB, we detected abundant levels of miR-125a, which were associated with tumor extension, grade, and recurrence. miR-125a stimulates stromal cell tumorigenicity and growth in vivo by promoting the expression of interleukin-17A (IL-17A) and β-catenin. In contrast, inhibition of miR-125a suppressed stromal cell tumorigenicity and growth. Then, we found that miR-125a stimulates IL-17A by targeting TET2 and Foxp3, and it stimulates β-catenin expression by targeting APC and GSK3β in stromal cells. Furthermore, we identified that IL-17A stimulates miR-125a by activating nuclear factor κB (NF-κB) signaling in stromal cells. Finally, our data show that simultaneous inhibition of IL-17A signaling and miR-125a more significantly inhibits stromal cell growth than miR-125a inhibition alone. miR-125a stimulates the progression of GCTB, and it might represent a useful candidate marker for progression. Simultaneously blocking miR-125a and IL-17A might represent a new therapeutic strategy for GCTB. Keywords: miR-125a, GCTB, recurrence, IL-17A, β-catenin signaling

The aim of the study was to investigate the association between environmental factors and nonsyndromic cleft of the lip and/or palate (NSCL/P) in Yantai District, China. A retrospective case-control study was carried out. A total of 236 NSCL/P children were selected from Department of Oral and Maxillofacial Surgery of Yantai Stomatological Hospital between September 2013 and December 2016 as cases; 209 controls were chosen from other diagnosis in the same department during the same period. The 2 groups matched age and sex. The parents of participants were inquired regarding the risk factors, and the answers were filled in a questionnaire by physicians. Chi-square and multivariate logistic regression analysis were used to analysis the data. There was significantly increased NSCL/P risk with high maternal age (P =0.002), family history (P = 0.001), abortion history (P = 0.033), poor parental education level (P = 0.008), maternal smoking (P = 0.044), maternal alcohol (P = 0.039), common cold or fever (P = 0.035), drug use (P = 0.006), and maternal stress (P = 0.049). Reduced NSCL/P risk was found with folic acid supplementation (P = 0.005), adequate maternal age (P = 0.002), and high parental education (P = 0.001). The proper amount of folic acid, the appropriate age of childbearing, and the high education were the protective factors of NSCL/P, whereas family history, abortion history, drug use during pregnancy, maternal tobacco and alcohol, and maternal stress were the risk factors for NSCL/P in Yantai District, China.

Background Subarachnoid hemorrhage (SAH) can induce apoptosis in many regions of the brain including the cortex and hippocampus. However, few studies have focused on apoptosis in the hypothalamus after SAH. Although some antiapoptotic strategies have been developed for SAH, such as anti-tumor necrosis factor-alpha (TNF-α) antibody, the molecular mechanisms underlying this condition have yet to be elucidated. Therefore, the purpose of this study was to evaluate whether SAH could induce apoptosis in the hypothalamus and identify the potential molecular mechanisms underlying the actions of anti-TNF-α antibody, as a therapeutic regimen, upon apoptosis. Materials and methods SAH was induced in a rat model. Thirty minutes prior to SAH, anti-TNF-α antibody or U0126, an extracellular signal-regulated kinase (Erk) inhibitor, was microinjected into the left lateral cerebral ventricle. In addition, phorbol-12-myristate-13-acetate was injected intraperitoneally immediately after the anti-TNF-α antibody microinjection. Then, real-time polymerase chain reaction, Western blotting and immunohistochemistry were used to detect the expression of caspase-3, bax, bcl-2, phosphorylated Erk (p-Erk) and Erk. Finally, anxiety-like behavior was identified by using open field. Results Levels of caspase-3, bax and bcl-2, all showed a temporary rise after SAH in the hypothalamus, indicating the induction of apoptosis in this brain region. Interestingly, we found that the microinjection of anti-TNF-α antibody could selectively block the elevated levels of bax, suggesting the potential role of anti-TNF-α antibody in the inhibition of SAH-induced apoptosis in the hypothalamus. Moreover, we found that Erk activation was necessary for apoptosis after SAH and that the microinfusion of anti-TNF-α antibody could inhibit apoptosis by suppressing the increase of p-Erk in the hypothalamus. Finally, our data indicated that the infusion of anti-TNF-α antibody could improve anxiety-like behavior. Conclusion Collectively, our data demonstrate that anti-TNF-α antibody attenuates apoptosis in the hypothalamus by inhibiting the activation of Erk, which plays an important role in the treatment of SAH., Video abstract

A facile, mild, and efficient dioxygen activation for the synthesis of isoxazoline/cyclic nitrone-featured α-ketols has been achieved by Cu-catalyzed trifunctionalization of internal unactivated alkynes of unsaturated ketoximes at room temperature. 18O isotope tracing and DFT calculation reveal that a cascade iminoxyl radical dichotomous 5-exo-dig cyclization/oxygen activation/peroxy radical 4-endo-trig cyclization process was involved in the reaction.

Relaxin family is a group of peptide hormones with a variety of biological functions by activating G protein-coupled receptors RXFP1–4. We recently developed bioluminescent tracers for their receptor-binding assays by chemical conjugation with the ultrasensitive NanoLuc reporter. To simplify preparation of the bioluminescent tracers, in the present study, we established a sortase-catalysed ligation approach using the chimeric R3/I5 as a model. Following catalysis by recombinant sortase A, a NanoLuc reporter carrying the LPETG sortase recognition motif at the C-terminus was efficiently ligated to an R3/I5 peptide carrying four successive Gly residues at the A-chain N-terminus, via the formation of a peptide bond between the C-terminal LPET sequence of NanoLuc and the A-chain N-terminal Gly residue of R3/I5. Saturation binding assays demonstrated that the NanoLuc-ligated R3/I5 retained high binding affinity to RXFP3 and RXFP4, with the calculated dissociation constants (K d) of 4.34 ± 0.33 nM (n = 3) and 5.66 ± 0.54 nM (n = 3), respectively. Using the NanoLuc-ligated R3/I5 as a tracer in competition binding assays, binding potencies of various ligands towards RXFP3 and RXFP4 were conveniently quantified. This work provides a simple method for rapid preparation of bioluminescent tracers for relaxin family peptides and other protein/peptide hormones for ligand–receptor interaction studies.