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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.
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Nanopartículas Metálicas , Nanopartículas , Eletrodos , NanotecnologiaRESUMO
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,ß-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.
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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,ß-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.
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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.
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Herein we describe a mild method for the dual C(sp3 )-H bond functionalization of saturated nitrogen-containing heterocycles through a sequential visible-light photocatalyzed dehydrogenation/[2+2] cycloaddition procedure. As a complementary approach to the well-established use of iminium ion and α-amino radical intermediates, the elusive cyclic enamine intermediates were effectively generated by photoredox catalysis under mild conditions and efficiently captured by acetylene esters to form a wide array of bicyclic amino acid derivatives, thus enabling the simultaneous functionalization of two vicinal C(sp3 )-H bonds.
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OBJECTIVE: 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). METHODS: 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. RESULTS: 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 (P <0. 05). Meanwhile,the same scores for the ZC II peptide-treated mice with CIA were significantly lower than the mice from CIA model group(P <0. 05). CONCLUSION: 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.
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Artrite Experimental/tratamento farmacológico , Colágeno Tipo II/uso terapêutico , Animais , Artrite , Artrite Experimental/induzido quimicamente , Eletroforese em Gel de Poliacrilamida , Articulações , Masculino , Camundongos , Camundongos Endogâmicos C57BLRESUMO
The selective C-C bond deconstruction/refunctionalization via a photoredox/nickel dual-catalyzed hydroalkylation of alkynes is developed under mild reaction conditions. In this protocol, a broad range of alkyl- and aryl-alkynes could react smoothly with cycloalkanols, affording the corresponding distal and site-specific vinyl-substituted ketones with high yields and excellent regioselectivities. Moreover, DFT calculations verified that the electron-rich behavior of aromatics and weak Brønsted bases have a common effect on the photocatalytic oxidant ring-opening of cyclobutanols.
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A protocol for the chemically divergent synthesis of ß-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 ß-lactam derivatives when DCM and CH3CN were used as solvents. However, when EtOH was used as the solvent, the intermediates underwent an intermolecular esterification reaction, and α-amino acid derivatives were produced. Detailed mechanistic experiments were conducted to prove that these two kinds of products came from the same intermediates. Furthermore, chemically diversified transformations of ß-lactam and α-amino acid derivatives were achieved.
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OBJECTIVES: Preclinical research is essential to the advancement of science but susceptible to insufficient reporting and methodological shortcomings, which compromise internal validity. We aimed to systematically assess the methodological and reporting quality of studies conducted on acupuncture for experimental cerebral ischemia/reperfusion injury (CIRI). METHODS: A comprehensive search in six databases was performed for animal research concerning acupuncture for CIRI. Two authors independently selected articles, extracted data, and assessed the methodological and reporting quality of identified articles using the Systematic Review Center for Laboratory Animal Experimentation (SYRCLE) tool, and Animal Research: Reporting In Vivo Experiments (ARRIVE) guideline, respectively. RESULTS: A total of 24 studies were identified. Only 1 article (4%) achieved a decent overall rating in using SYRCLE (percentage of items with "low risk" ⩾50%). Of the 22 items on the SYRCLE tool, only 8 items (37%) were rated as "low risk" of bias in more than 50% of the included studies. Of the 39 items of ARRIVE, 20 (51%) items were rated as "low risk" in more than 50% of the included studies. CONCLUSIONS: The methodological and reporting quality of included studies was generally low, which demands further improvement. These findings should inform the development of evidence-based guidelines for future preclinical research assessing the effect of acupuncture on CIRI.
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Terapia por Acupuntura/normas , Isquemia Encefálica/terapia , Traumatismo por Reperfusão/terapia , Pontos de Acupuntura , Terapia por Acupuntura/métodos , Feminino , Humanos , MasculinoRESUMO
BACKGROUND: 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. METHODS: 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. RESULTS: This study aimed to evaluate the current status of UA treatment for insomnia, with the aim of illustrating the effectiveness and safety of UA. CONCLUSION: This study will provides a high-quality evidence to evaluate the effectiveness and safety of UA in treating insomnia. REGISTRATION: PROSPERO CRD42021283036.
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Terapia por Acupuntura , Distúrbios do Início e da Manutenção do Sono/terapia , Humanos , Metanálise como Assunto , Qualidade do Sono , Revisões Sistemáticas como AssuntoRESUMO
OBJECTIVE: To investigate the antidepressant-like effects of Chaihu Shugan Powder (CSP, ) and to explore its underlying mechanisms. METHODS: 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. RESULTS: 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 (P<0.05), an increased preference for sucrose, and longer swimming time and shorter immobility time during the FST (all P<0.05). In addition, CSP treatment significantly reduced the rate of apoptosis in rat hippocampal neurons (P<0.05). 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 P<0.05), whereas total and phosphorylated JNK1 protein levels did not differ significantly between control and CSP-treated rats. CONCLUSION: CSP can improve depression-like behavior in rats exposed to CUMS, possibly by suppressing CHOP and caspase-12 mediated apoptosis in the rat hippocampus.
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Estresse do Retículo Endoplasmático , Animais , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Apoptose , Depressão/tratamento farmacológico , Modelos Animais de Doenças , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Hipocampo , Pós/farmacologia , Ratos , Ratos Sprague-Dawley , Estresse Psicológico/complicações , Estresse Psicológico/tratamento farmacológicoRESUMO
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.
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Autofagia/efeitos da radiação , Isquemia Encefálica/metabolismo , Eletroacupuntura , Proteínas do Tecido Nervoso/metabolismo , Sirtuína 1/metabolismo , Animais , Autofagossomos/metabolismo , Masculino , Neuroproteção/efeitos da radiação , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Transdução de Sinais/efeitos da radiaçãoRESUMO
Electroacupuncture is known as an effective adjuvant therapy in ischemic cerebrovascular disease. However, its underlying mechanisms remain unclear. Studies suggest that autophagy, which is essential for cell survival and cell death, is involved in cerebral ischemia reperfusion injury and might be modulate by electroacupuncture therapy in key ways. This paper aims to provide novel insights into a therapeutic target of electroacupuncture against cerebral ischemia/reperfusion injury from the perspective of autophagy. Here we review recent studies on electroacupuncture regulation of autophagy-related markers such as UNC-51-like kinase-1 complex, Beclin1, microtubule-associated protein-1 light chain 3, p62, and autophagosomes for treating cerebral ischemia/reperfusion injury. The results of these studies show that electroacupuncture may affect the initiation of autophagy, vesicle nucleation, expansion and maturation of autophagosomes, as well as fusion and degradation of autophagolysosomes. Moreover, studies indicate that electroacupuncture probably modulates autophagy by activating the mammalian target of the rapamycin signaling pathway. This review thus indicates that autophagy is a therapeutic target of electroacupuncture treatment against ischemic cerebrovascular diseases.
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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 â ¡ light chain 3 (LC3â ¡) and the ratio of LC3-â ¡/LC3-â 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.
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Terapia por Acupuntura , Autofagia , Traumatismo por Reperfusão , Animais , Proteína Beclina-1 , Fosfatidilinositol 3-QuinasesRESUMO
OBJECTIVE: 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. METHODS: Thirty-three male Sprague-Dawley rats were randomly divided into sham operation, model and EA groups (n=11 in each group). EA (2 Hz/15 Hz, 1 mA) was applied to "Baihui"(GV20), "Quchi" (LI11) and "Zusanli" (ST36) for 30 min, once daily for 5 days, followed by establishment of CIRI model by occlusion of the middle cerebral artery (MCAO) for 1.5 h and reperfusion for 24 h. The neurological deficit score was assessed in reference to Longa's methods, and the infarct volume assessed by 2,3,5-triphenyltetrazolium chloride staining. The density of dendrite spines of neurons in the ischemic cerebral cortex tissue was detected by Golgi's staining, the autophagosome observed by electron microscopy, and the expression levels of microtubule-associated protein 1 light chain 3 (LC3) and p62 (a selective autophagy substrate) were detected by Western blot. RESULTS: Compared with the sham operation group, the neurological deficit score and infarct volume were significantly increased (P<0.01), the number of autophagosomes and the ratio of LC3-â ¡/LC3-â also significantly increased (P<0.01), while the expression level of p62 was notably decreased in the model group (P<0.01). Following the intervention and in comparison with the model group, the neurological deficit score and infarct volume were significantly reduced (P<0.01), the number of autophagosomes and the ratio of LC3-â ¡/LC3-â obviously decreased (P<0.01), and the expression of p62 was significantly up-regulated in the EA group (P<0.01). CONCLUSION: EA pretreatment is effective in improving CIRI in rats, which may be realized through suppressing autophagy in the ischemic cerebral cortex tissue.
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Autofagia , Isquemia Encefálica , Eletroacupuntura , Traumatismo por Reperfusão , Animais , Isquemia Encefálica/terapia , Córtex Cerebral , Masculino , Ratos , Ratos Sprague-DawleyRESUMO
OBJECTIVE: The objective of the present study is to investigate the inhibitory effects of sinomenine (SIN) on angiogenesis in a collagen-induced arthritis (CIA) mouse model. METHODS: Arthritis assessments for all mice were recorded. The histopathological assessments were performed following haematoxylin and eosin (HE) staining. Immunohistochemistry and enzyme-linked immunosorbent assay (ELISA) analyses were used to detect the expression of hypoxia-inducible factor-1α (HIF-1α), vascular endothelial growth factor (VEGF) and angiopoietin 1 (ANG-1) in the serum and in the membrane. Immunohistochemistry was employed to detect the synovium microvessel density (MVD). RESULTS: Compared with the CIA model group, SIN significantly ameliorated swelling and erythema extension, decreased the arthritis index, reduced inflammation, cartilage damage and bone erosion, and lessened the number of CD31 positive cells on the synovium. Moreover, the levels of HIF-1α, VEGF and ANG-1 in the synovium and in the peripheral serum were increased in the untreated CIA model group but were significantly reduced in the 30 mg/kg, 100 mg/kg and 300 mg/kg SIN treatment groups. CONCLUSION: SIN could mitigate CIA by inhibiting angiogenesis, and the mechanism may associate with the HIF-1α-VEGF-ANG-1 axis. Additionally, our study provides a referable experimental basis for the use of SIN for the treatment of rheumatoid arthritis.
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Inibidores da Angiogênese/farmacologia , Artrite Experimental/tratamento farmacológico , Morfinanos/farmacologia , Neovascularização Patológica/tratamento farmacológico , Angiopoietina-1/metabolismo , Animais , Antirreumáticos/farmacologia , Artrite Experimental/fisiopatologia , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/fisiopatologia , Colágeno/toxicidade , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Patológica/patologia , Membrana Sinovial/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
OBJECTIVE: 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. METHODS: 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" (TF4) and "Yidan" (CO11), combined with sound masking; the treatment was given once a day for 15 days. The gap prepulse inhibition of acoustic startle (GPIAS) and prepulse inhibition (PPI) testing were performed using the acoustic startle reflex starter package for rats. The expression of BDNF, TrkB, CREB and p-CREB in the auditory cortex of each group were measured with Western Blot analysis. RESULTS: â 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 (all P<0.05); compared with the model group, GPIAS values in 12 kHz, 16 kHz, 20 kHz and 28 kHz were significantly increased in the EAS group (all P<0.05). â¡ Compared with the control group, the expression of BDNF and p-CREB in the model group was significantly increased (P<0.01), and the expression of TrkB in the model group was significantly increased (P<0.05); the differences of expression of BDNF, TrkB, CREB and p-CREB between the model group and the EAS group had no statistics significance (all P>0.05). CONCLUSION: EAS 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.
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Pontos de Acupuntura , Córtex Auditivo , Zumbido , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Estimulação Elétrica , Masculino , Ratos , Ratos Sprague-Dawley , Receptor trkB/metabolismo , Zumbido/metabolismo , Zumbido/terapiaRESUMO
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.
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To assess the efficacy and safety of the combination of total glucoside of peony (TGP) and methotrexate (MTX) for the treatment of rheumatoid arthritis (RA). Randomized controlled trial (RCT) data on the traditional Chinese active component TGP combined with MTX vs. MTX alone for the treatment of RA was collected by searching the Pubmed, Embase, Cochrane Library, CNKI, VIP Journals database, and Wanfang database up to February 2017. Study selection, data extraction, data synthesis, and data analyses were performed according to the Cochrane standards. A total of eight RCTs involving 522 participants were included in this meta-analysis. Compared with MTX alone, the use of TGP combined with MTX exhibited better therapeutic effects for the treatment of RA (P = 0.004). In addition, TGP combined with MTX caused a more significant decrease in erythrocyte sedimentation rate (ESR) (P < 0.0001) and swollen joint count (SJC) (P < 0.00001). However, no significant differences were found in C-reactive protein (CRP) (P = 0.19), duration of morning stiffness (DMS) (P = 0.32), or tender joint count (TJC) (P = 0.23) between the two groups. In addition, adverse events were more frequently reported in the MTX monotherapy group than in the TGP and MTX combination group (P = 0.0007). Our study demonstrates that TGP combined with MTX is more effective than MTX alone for the treatment of RA. Nevertheless, the adverse effects of the combination of TGP and MTX need to be further assessed. Due to the poor methodological quality of included trials, well-designed, multi-center, and large-scale RCTs are necessary to draw a more definitive conclusion.
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Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Glucosídeos/uso terapêutico , Metotrexato/uso terapêutico , Paeonia , Extratos Vegetais/uso terapêutico , Quimioterapia Combinada , Humanos , Fitoterapia , Resultado do TratamentoRESUMO
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.