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A protocol for the chemically divergent synthesis of β-lactams and α-amino acid derivatives with isothiourea (ITU) catalysis by switching solvents was developed. The stereospecific Mannich reaction occurring between imine and C(1)-ammonium enolate generated zwitterionic intermediates, which underwent intramolecular lactamization and afforded β-lactam derivatives when DCM and CH

Herein, we report a general strategy for the rational design of an efficient organic photocatalyst, and we describe a robust method for the direct C(sp3)–H carbamoylation of saturated aza-heterocyc...

A photocatalytic tandem cyclization of o-alkenylbenzaldehydes using pyridinium salts as the amination reagent is described. A variety of valuable seven-membered nitrogenous heterocyclic skeletons are prepared in modest to excellent yields in concise one-step. This transformation features mild reaction conditions and exceptional functional group tolerance. In addition, combining control experiments and density functional theory (DFT) calculations on the mechanism can explain the reaction selectivity.

A photoredox/nickel dual-catalyzed hydroalkylation of alkyl- and aryl-alkynes with cycloalkanols for the rapid construction of distal and site-specific vinyl-substituted ketones derivatives is described.

Accurate size analysis of nanoparticles (NPs) is vital for nanotechnology. However, this cannot be realized based on conventional single-nanoparticle collision (SNC) because the current intensity, a thermodynamic parameter of SNC for sizing NPs, is always smaller than the theoretical value due to the effect of NP movements on the electrode surface. Herein, a size-dependent dynamic parameter of SNC, current lifetime, which refers to the time that the current intensity decays to 1/e of the original value, was originally utilized to distinguish differently sized NPs. Results showed that the current lifetime increased with NP size. After taking the current lifetime into account rather than the current intensity, the overlap rates for the peak-type current transients of differently sized Pt NPs (10 and 15 nm) and Au NPs (18 and 35 nm) reduced from 73 and 7% to 45 and 0%, respectively, which were closer to the theoretical values (29 and 0%). Hence, the proposed SNC dynamics-based method holds great potential for developing reliable electrochemical approaches to evaluate NP sizes accurately.

Cerebral ischemia/reperfusion (CIR) injury occurs when blood flow is restored in the brain, causing secondary damage to the ischemic tissues. Previous studies have shown that electroacupuncture (EA) treatment contributes to brain protection against CIR injury through modulating autophagy. Studies indicated that SIRT1-FOXO1 plays a crucial role in regulating autophagy. Here we investigated the mechanisms underlying the neuroprotective effect of EA and its role in modulating autophagy via the SIRT1-FOXO1 signaling pathway in rats with CIR injury. EA pretreatment at “Baihui”, “Quchi” and “Zusanli” acupoints (2/15Hz, 1mA, 30 min/day) was performed for 5 days before the rats were subjected to middle cerebral artery occlusion, and the results indicated that EA pretreatment substantially reduced the Longa score and infarct volume, increased the dendritic spine density and lessened autophagosomes in the peri-ischemic cortex of rats. Additionally, EA pretreatment also reduced the ratio of LC3-II/LC3-I, the levels of Ac-FOXO1 and Atg7, and the interaction of Ac-FOXO1 and Atg7, but increased the levels of p62, SIRT1, and FOXO1. The above effects were abrogated by the SIRT1 inhibitor EX527. Thus, we presume that EA pretreatment elicits a neuroprotective effect against CIR injury, potentially by suppressing autophagy via activating the SIRT1-FOXO1 signaling pathway.

A series of inexpensive, easily tunable, and highly reducing organic photocatalysts (PCs) that exhibit strong absorption in the visible region are described. Time-dependent density functional theory calculations were applied to corroborate the experimental observations and explain the relationship between the structure and property. The photocatalytic efficiency of these PCs was demonstrated by catalyzing several challenging reactions and the radical cascade cyclization of 1,6-diyne with superior photocatalytic efficiency to other organic photocatalysts.

To investigate the effect of electroacupuncture (EA) preconditioning on autophagy in cerebral cortex tissues of rats with cerebral ischemia-reperfusion injury (CIRI), so as to explore its mechanisms underlying improvement of CIRI.Thirty-three male Sprague-Dawley rats were randomly divided into sham operation, model and EA groups (Compared with the sham operation group, the neurological deficit score and infarct volume were significantly increased (EA pretreatment is effective in improving CIRI in rats, which may be realized through suppressing autophagy in the ischemic cerebral cortex tissue.

Due to the significance of hybrid systems in drug discovery, there is an urgent need to assemble multiple biologically active ingredients into a single molecule. Here, we report a general transition-metal-free selective C-H benzylation of tertiary arylamines in good to excellent yields with a broad substrate scope and high functional-group tolerance under mild conditions. Besides arylamines, some other benzene derivatives also readily furnished the corresponding diaryl methane derivatives with this protocol. A series of control experiments and theoretical calculations indicated that this transition-metal-free reaction is a dearomatization-aromatization process.

Insomnia is characterized by high incidence, easy recurrence, and difficulty in curing. Serious insomnia not only seriously affects the body organ function but also causes great damage psychological.Umbilical acupuncture (UA) has fewer side effects and is increasingly used to treat insomnia. This study aimed to systematically review the effectiveness and safety of UA in the treatment of insomnia.Literature on UA for insomnia in PubMed, Excerpt Medica Database, the Cochrane Central Register of Controlled Trials, Web of Science, China National Knowledge Infrastructure Database, China Biomedical Literature Database, Chinese Scientific Journal Database, and Wan Fang Database were searched from the creation of these databases to October 3, 2021. In addition, the reference lists of studies meeting the inclusion criteria will also be searched to achieve a comprehensive retrieval of the maximum. All randomized controlled trials of UA for treating insomnia were included. Two reviewers will conduct literature screening, data extraction, and quality evaluation respectively. The main outcome was the Pittsburgh Sleep Quality Index, and the secondary outcomes included clinical efficacy, and safety. RevMan 5.4.1 software was used for mate analysis.This study aimed to evaluate the current status of UA treatment for insomnia, with the aim of illustrating the effectiveness and safety of UA.This study will provides a high-quality evidence to evaluate the effectiveness and safety of UA in treating insomnia.PROSPERO CRD42021283036.

We herein report a general organocatalytic enantioselective strategy for the construction of highly strained spiro[2,3]hexane skeletons from methylenecyclopropanes and a broad selection of α,β-unsaturated aldehydes. The reaction proceeds through a Michael addition followed by ring expansion of methylenecyclopropanes and nucleophilic attack of an enamine to realize the construction of spiro[2,3]hexanes. Key to the success of this approach are the utilization of an electron-deficient difluoro-substituted secondary amine catalyst and the intrinsic reactivity of methylenecyclopropanes.

Excessive autophagy is one of the crucial factors of cerebral ischemia-reperfusion injury (CIRI), which has been demonstrated to be one of the targets for acupuncture treatment of ischemic stroke. In the present paper, we make a review about the development of acupuncture intervention induced improvement of CIRI (such as reducing the infarction area, improving learning-memory ability and motor function) by regulating autophagy in animal studies. Outcomes showed that acupuncture intervention can function in 1) inhibiting CIRI-induced increase of the number of lysosomes and autophagic lysosomes, and relieving structural injury of mitochondria, and reducing the number of autophagosome in the central region of the ischemic cerebral cortex tissue; 2) down-regulating the expression of microtubule-associated protein Ⅱ light chain 3 (LC3Ⅱ) and the ratio of LC3-Ⅱ/LC3-Ⅰ in the ischemic cerebral region, and 3) regulating the expression of Beclin 1 (autophagy-related gene), promoting the expression of P62 (autophagy-related adaptor protein). In addition, acupuncture can also regulate phosphoinositide 3 kinase (PI3K)- protein kinase B (AKT)- mammalian target of rapamycin complex 1(mTOR) signaling at different time-points (down-regulation at the early stage and up-regulation at the later stage), and activating AMP-activated protein kinase (AMPK)-mTOR- UNC51-like kinase-1 signaling to relieve cerebral ischemic injury. These results reveal some mechanisms of acupuncture therapy underlying improvement of CIRI and provide experimental basis for clinical application of acupuncture therapy in the treatment of ischemic stroke.

To explore the effect of electrical stimulation at auricular points (EAS) combined with sound masking on the expression of cAMP-response element binding protein (CREB), brain-derived neurotrophic factor (BDNF) and tyrosine receptor kinase B (TrkB) in the auditory cortex of tinnitus rats.A total of 27 adult male SD rats were randomly divided into a control group, a model group and an EAS group. The rats in the model group and the EAS group were intervened with intraperitoneal injection of sodium salicylate to induce tinnitus model, while the rats in the control group were intervened with injection of 0.9% NaCl solution. After the model was successfully established, the rats in the EAS group were treated with electrical stimulation at "Shenmen" (TF① Compared with the control group, the GPIAS values in 12 kHz, 16 kHz, 20 kHz and 28 kHz were significantly decreased in the model group (allEAS could improve the GPIAS values of high-frequency background sound in tinnitus rats, which may be related with the upregulation of the BDNF/TrkB/CREB signaling pathway in the auditory cortex, leading to the reversion of the maladaptive plasticity.

To investigate the antidepressant-like effects of Chaihu Shugan Powder (CSP, ) and to explore its underlying mechanisms.Thirty-two Sprague-Dawley rats were randomly divided into control (CON), chronic unpredictable mild stress (CUMS), fluoxetine (FLU), and CSP groups, 8 rats in each group. All of the rats except for those in the control group were subjected to 3 consecutive weeks of CUMS to establish the depression model. The open field test (OFT), forced swimming test (FST), and sucrose preference test were used to assess the anti-anxiety and antidepressant effects of CSP. Terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling was used to determine the apoptosis rate in the hippocampal tissues. The mRNA and protein levels of glucose-regulated protein (GRP) 78, spliced X-box-binding protein (XBP)-1, CCAAT/enhancer-binding protein homologous protein (CHOP), caspase-12, and c-Jun N-terminal kinase (JNK) in the hippocampus of rats were evaluated by real-time PCR and Western blot analysis, respectively.Administration of CSP alleviated anxiety and depression-like behavior in CUMS rats, as revealed by enhanced time and distance in the center of the OFT (P0.05), an increased preference for sucrose, and longer swimming time and shorter immobility time during the FST (all P0.05). In addition, CSP treatment significantly reduced the rate of apoptosis in rat hippocampal neurons (P0.05). The mRNA and protein expression levels of GRP78, spliced XBP-1, and CHOP were down-regulated along with the expression of caspase-12 and cleaved caspase-12 proteins (all P0.05), whereas total and phosphorylated JNK1 protein levels did not differ significantly between control and CSP-treated rats.CSP can improve depression-like behavior in rats exposed to CUMS, possibly by suppressing CHOP and caspase-12 mediated apoptosis in the rat hippocampus.

Herein, we describe a novel and efficient method for constructing a series of fluorine-containing γ-keto acid derivatives through combining visible-light photoredox catalysis and chiral Lewis acid catalysis. With this dual catalytic strategy, a variety of chiral γ-keto amides containing a gem-difluoroalkyl group and a series of fluorine-containing α,β-unsaturated-γ-keto esters were successfully constructed with high stereoselectivities, respectively. A series of experiments showed that the chemoselectivity of this process was highly dependent on the fluorine reagents besides the Lewis acid catalysts. This approach facilitates rapid access to γ-keto acid derivatives, an important class of precursors for pharmaceuticals, plasticizers, and various other additives.

Geum japonicum Thunb. var. chinense (GJ) is a type of wild vegetable found in China and other Asian countries; it has been reported that its extracts possess a neuroprotective effect against cerebral ischemia reperfusion (CIR) injury. The aim of this study is to explore the effect GJ extracts on transient focal CIR injury and neurons apoptosis and to clarify its possible underlying mechanisms in vivo. Our results indicated that pretreatment with GJ extracts significantly ameliorated the infarct volume, decreased neurological deficits, lessened neural cells apoptosis, downregulated GFAP activity level, and increased surviving neurons. Moreover, GJ extracts preadministration increased Bcl-2 levels and attenuated the increase in the expressions of Bax and it also lowered the cleaved caspase-3 activity in ischemic cortex tissues which was caused by CIR and increased the expression of PI3K and p-Akt. The above effects of high dose of GJ (GJ-H) group were much better than those of low dose of GJ (GJ-L), which indicated that GJ extracts may be helpful in the suppression of CIR injury with a dose-dependent manner.

Herein we describe a mild method for the dual C(sp

There is no abc axis system model of synchronous generator in the SimPowerSystem (SPS) of Simulink but the model of dq axis system ，and the model of generator in SPS is lack of flexible tuning function of variable. In this paper a model of synchronous generator is established in abc axis system, which is based on the Simulink software. This model is consist of basic calculation module in the Simulink is created to solve the above problems. Using the model simulates a rotating-rectifier brushless synchronous generator system of planes and the simulation results indicate that the model is accurate enough.

This paper studies the output-feedback variable structure control for MIMO (multi-input multi-output) linear systems with generalized relative degree one. A new variable structure control scheme is proposed within the framework of model reference control. Under the assumption that the high frequency gain matrix of the plant can be transformed to a main diagonal dominant matrix via full rank transformation, it is shown that all signals of the closed-loop system are globally uniformly bounded and meanwhile, the tracking error converges to zero exponentially. Simulation results are presented to illustrate the effectiveness of the proposed scheme.

Puerarin suppresses autophagy to alleviate cerebral ischemia/reperfusion injury, and accumulating evidence indicates that the AMPK-mTOR signaling pathway regulates the activation of the autophagy pathway through the coordinated phosphorylation of ULK1. In this study, we investigated the mechanisms underlying the neuroprotective effect of puerarin and its role in modulating autophagy via the AMPK-mTOR-ULK1 signaling pathway in the rat middle cerebral artery occlusion model of cerebral ischemia/reperfusion injury. Rats were intraperitoneally injected with puerarin, 50 or 100 mg/kg, daily for 7 days. Then, 30 minutes after the final administration, rats were subjected to transient middle cerebral artery occlusion for 90 minutes. Then, after 24 hours of reperfusion, the Longa score and infarct volume were evaluated in each group. Autophagosome formation was observed by transmission electron microscopy. LC3, Beclin-1 p62, AMPK, mTOR and ULK1 protein expression levels were examined by immunofluorescence and western blot assay. Puerarin substantially reduced the Longa score and infarct volume, and it lessened autophagosome formation in the hippocampal CA1 area following cerebral ischemia/reperfusion injury in a dose-dependent manner. Pretreatment with puerarin (50 or 100 mg/kg) reduced Beclin-1 expression and the LC3-II/LC3-I ratio, as well as p-AMPK and pS317-ULK1 levels. In comparison, it increased p62 expression. Furthermore, puerarin at 100 mg/kg dramatically increased the levels of p-mTOR and pS757-ULK1 in the hippocampus on the ischemic side. Our findings suggest that puerarin alleviates autophagy by activating the APMK-mTOR-ULK1 signaling pathway. Thus, puerarin might have therapeutic potential for treating cerebral ischemia/reperfusion injury.

To analyze the homology of Zaocys type 1I collagen ( ZC II ) with the C II collagen from other species, and to investigate the effect of ZC II on arthritis in mice with collagen-induced arthritis (CIA).ZC II was purified with restriction pepsin digestion. Then SDS-PAGE gel electrophoresis and UV spectrophotometry were used to identify the protein,the homology of the ZC II peptide was analyzed with Mass Spectrometry. The model of CIA mice were induced by subcutaneous injection of Chicken C II into male C57BL/6 mice from the base of the tails. After immunization,ZC II [H,M,L:40,20 and 10 μg/(kgd) ]was administered orally to mice from day 21 to 28 accordingly. The severity of the arthritis in each limb was evaluated using a macroscopic scoring system, and his- topathological change of joint was observed by light microscope with HE staining.The molecular weight of ZC II protein deter- mined by SDS-PAGE gel electrophoresis was between 110 kD and 140 kD, and UV absorption peak appeared at around 230 nm in wave- length. The peptide mass fingerprinting(PMF) of the purified protein by Mass Spectrometry analysis showed that it had at least 4 peptides matched with other species,and the protein score was greater than 95%. Compared with normal group,the CIA model group had significantly higher scores for arthritis and histopathological changes (P0. 05). Meanwhile,the same scores for the ZC II peptide-treated mice with CIA were significantly lower than the mice from CIA model group(P0. 05).Results of Mass Spectrometry analysis demonstrate that ZC II has high homology with the C II from other species. Oral administration of ZC II can suppress arthritis in mice with CIA and ameliorate the histopathological changes of the joint.

Objective.To determine the role of natural killer (NK)-22 cells in the pathogenesis of rheumatoid arthritis (RA).Methods.Using flow cytometry, the proportions of NK-22 cells and intracellular contents of perforin, granzyme B, and interferon-γ (IFN-γ) were determined in the peripheral blood (PB) and synovial fluid (SF) of patients with RA and healthy individuals. The levels of interleukin 22 (IL-22) and tumor necrosis factor-α (TNF-α) in the NK-22 supernatant and gene expressions were measured using ELISA and QuantiGene Plex assay, respectively. The effect of NK-22 supernatant on the proliferation of fibroblast-like synoviocytes (FLS) and recombinant human IL-22 (rhIL-22) on the production of monocyte chemoattractant protein 1 (MCP-1) by RA FLS was detected using the yellow tetrazolium salt method and ELISA, respectively. The relationship between the proportions of NK-22 cells and disease activity was analyzed.Results.NKp44 and CCR6 were expressed in a larger population of SF NK cells than in the PB NK cells of patients with RA. NK-22 cells produce low content of perforin, granzyme B, and IFN-γ. NK-22 cellsin vitrocan secrete IL-22 and TNF-α and there was increased messenger RNA coding for IL-22 and TNF-α. NK-22 supernatant can induce the proliferation of RA FLS. Addition of IL-22 antibody plus TNF-α antibody inhibited the proliferation of FLS induced by the NK-22 supernatant. Both rhIL-22 1 ng/ml and rhIL-22 10 ng/ml induced the production of MCP-1 by RA FLS. The NK-22 proportions were positively correlated with disease activity.Conclusion.NK-22 cells are increased in patients with RA and might play a role in the pathogenesis of RA through the production of IL-22 and TNF-α. The proportion of NK-22 cells and disease activity were highly correlated.

To investigate the effect of NK-22 cells isolated from the synovial fluid (SF) of patients with rheumatoid arthritis (RA) on the proliferation of fibroblast-like synoviocytes and explore its possible mechanism.The proportions of NK-22 cells in the peripheral blood (PB) and the SF of 20 RA patients and 20 healthy individuals were determined by flow cytometry. NK-22 cells in the SF sorted by flow cytometry were cultured for two weeks followed by a 4-h stimulation with 20 ng/ml phorbol 12-myristate 13-acetate and 0.5 µ mol/L ionomycin. The culture supernatant of NK-22 cells was then harvested, in which the levels of IL-22 and TNF-α were measured by ELISA. The fibroblast-like synoviocytes were exposed to the culture supernatant for 24, 48, 72, and 96 h, and the changes in the cell proliferation were detected by MTT assay.RA patients showed a significantly greater proportion of NK-22 cells in both the SF and PB than the normal control subjects (P0.05). NK-22 cells sorted by flow cytometry reached a purity exceeding 90%, and the levels of IL-22 and TNF-α in the culture supernatant of NK-22 cells cultured for two weeks were 941.16 pg/ml and 368.1 pg/ml, respectively. The culture supernatant of NK-22 cells caused a rapid proliferation of the fibroblast-like synoviocytes at 24, 48, 72, and 96 h after the exposure.NK-22 cells in the SF of RA patients can promote the proliferation of fibroblast-like synoviocytes possibly due to the capacity of NK-22 cells to produce IL-22 and TNF-α.

To investigate the expression levels of miR-146a and miR -16 in the peripheral blood mononuclear cells (PBMCs) of patients with rheumatoid arthritis (RA) and their correlation to the disease activity.The expression levels of miR-146a and miR-16 in the in PBMCs were measured using real-time RT-PCR in 40 RA patients and 16 healthy individuals. The correlations of miR-146a and miR-16 expressions to the disease activity of RA were analyzed.The expression levels of miR-146a and miR-16 in the PBMCs of RA patients increased significantly compared to those in the healthy individuals (P0.05). Their expression levels was significantly higher in active RA patients than in patients with disease remission (P0.05) and healthy individuals (P0.01). The expression levels of miR-146a and miR-16 were positively correlated to ESR, CRP and the disease activity scores in 28 joints (DAS28) (P0.01), but not to RF (P0.05).The elevated expression levels of miR-146a and miR-16 are correlated to RA disease activity, suggesting their value in assessment of the clinical disease activity of RA.

To explore the association of the expressions of human leukocyte antigen (HLA)-DR4, peptidyl arginine deiminase type4(PAD4), and signal transducer and activator of transcription 4 (STAT4) in the peripheral blood with the disease activity in patients with rheumatoid arthritis (RA).Twenty-four RA patients in active stage (DAS28 scoreor=2.6) and 14 RA patients in remission stage (DAS28 score2.6) were enrolled in this study, with 12 healthy volunteers as the control. The QuantiGene Plex method was used to measure the expression level of HLA-DR4, PAD4, and STAT4 mRNA, and the relationship between the expressions of these genes and the DAS28 score, levels of anti-cyclic citrullinated peptide antibody (anti-CCP antibody) and rheumatoid factor (RF) was analyzed.The expressions of HLA-DR4, PAD4, and STAT4 were significantly higher in RA patients than in the healthy controls (P0.05). The level of HLA-DR4 mRNA in the two RA groups showed no significant difference, but was significantly higher than that in the healthy controls. HLA-DR4 expression was not found to correlated to DAS28 score, anti-CCP antibody level or RF in the RA patients. The expressions of PAD4 and STAT4 were significantly different between the two RA groups (P0.05). In the RA patients, PAD4 mRNA expression was positively correlated to DAS28 and anti-CCP antibody level (P0.05), and STAT4 expression showed positive correlations to DAS28 and RF levels (P0.05).HLA-DR4, PAD4 and STAT4 are overexpressed in RA patients and may be involved in the pathogenesis of RA. The expressions of PAD4 and STAT4, but not HLA-DR4, are closely related to the disease activity of RA. Detection of peripheral blood PAD4 and STAT4 expressions can be helpful for evaluating the disease activity of RA.