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Synthetic lethality (SL) occurs when mutations in two genes together lead to cell or organism death, while a single mutation in either gene does not have a significant impact. This concept can also be extended to three or more genes for SL. Computational and experimental methods have been developed to predict and verify SL gene pairs, especially for yeast and Escherichia coli. However, there is currently a lack of a specialized platform to collect microbial SL gene pairs. Therefore, we designed a synthetic interaction database for microbial genetics that collects 13,313 SL and 2,994 Synthetic Rescue (SR) gene pairs that are reported in the literature, as well as 86,981 putative SL pairs got through homologous transfer method in 281 bacterial genomes. Our database website provides multiple functions such as search, browse, visualization, and Blast. Based on the SL interaction data in the S. cerevisiae, we review the issue of duplications' essentiality and observed that the duplicated genes and singletons have a similar ratio of being essential when we consider both individual and SL. The Microbial Synthetic Lethal and Rescue Database (Mslar) is expected to be a useful reference resource for researchers interested in the SL and SR genes of microorganisms. Mslar is open freely to everyone and available on the web at http://guolab.whu.edu.cn/Mslar/.
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Neoplasias , Saccharomyces cerevisiae , Humanos , Saccharomyces cerevisiae/genética , Mutações Sintéticas Letais , Mutação , Genoma Bacteriano/genética , Bases de Dados Genéticas , Neoplasias/genéticaRESUMO
Cold-heat combination is a common method in the treatment of ulcerative colitis, which is represented by classic drug pair, Coptidis Rhizoma and Zingiberis Rhizoma.The present study explored the synergetic effects of berberine and 6-shogaol, the primary components of Coptidis Rhizoma and Zingiberis Rhizoma, respectively, on intestinal inflammation and intestinal flora in mice with ulcerative colitis to reveal the effect and mechanism of cold-heat combination in the treatment of ulcerative colitis.The ulcerative colitis model was induced by dextran sulfate sodium(DSS) in mice.The model mice were administered with berberine(100 mg·kg~(-1)), 6-shogaol(100 mg·kg~(-1)), and berberine(50 mg·kg~(-1)) combined 6-shogaol(50 mg·kg~(-1)) by gavage, once per day.After 20 days of drug administration, mouse serum, colon tissues, and feces were sampled.Hematoxylin-eosin(HE) staining was used to observe histopathological changes in colon tissues.Alcian blue/periodic acid-Schiff(AB/PAS) staining was used to observe the changes in the mucus layer of colon tissues.Enzyme-linked immunosorbent assay(ELISA) was employed to detect the serum content of tumor necrosis factor-α(TNF-α), interleukin-1ß(IL-1ß), and interleukin-6(IL-6).Immunohistochemical method was adopted to detect the protein expression of macrophage surface markers F4/80, mucin-2, claudin-1, and zonula occludens-1(ZO-1) in colon tissues.High-throughput Meta-amplicon library sequencing was used to detect changes in the intestinal flora of mice.The results indicated that the 6-shogaol group, the berberine group, and the combination group showed significantly relieved intestinal injury, reduced number of F4/80-labeled positive macrophages in colon tissues, increased protein expression of mucin-2, claudin-1, and ZO-1, and decreased serum le-vels of TNF-α, IL-1ß, and IL-6.Shannon, Simpson, Chao, and Ace indexes of the intestinal flora of mice in the 6-shogaol group and the combination group significantly increased, and Chao and Ace indexes in the berberine group significantly increased.As revealed by the bioinformatics analysis of intestinal flora sequencing, the relative abundance of Verrucomicrobia at the phylum, class, and order levels decreased significantly in all treatment groups after drug administration, while that of Bacillibacteria gradually increased.In the 6-shogaol group and the combination group, Akkermansia muciniphila completely disappeared, but acid-producing bacillus still existed in large quantities.As concluded, both 6-shogaol and berberine can inhibit intestinal inflammation, reduce the infiltration and activation of macrophages, relieve intestinal damage, reduce intestinal permeability, improve the structure of flora, and promote intestinal microecological balance.The combined application of berberine and 6-shogaol has a significant synergistic effect.
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Berberina , Colite Ulcerativa , Colite , Medicamentos de Ervas Chinesas , Animais , Berberina/farmacologia , Berberina/uso terapêutico , Catecóis , Claudina-1/metabolismo , Claudina-1/farmacologia , Claudina-1/uso terapêutico , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/metabolismo , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Colo , Sulfato de Dextrana/efeitos adversos , Sulfato de Dextrana/metabolismo , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/farmacologia , Inflamação/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Mucina-2/metabolismo , Mucina-2/farmacologia , Fator de Necrose Tumoral alfa/metabolismoRESUMO
BACKGROUND: Macrosomia is a major adverse pregnancy outcome of gestational diabetes mellitus (GDM). Although BMI, symphysis-fundal height (SFH) and abdominal circumference (AC) are associated with foetal weight, there are some limitations to their use, especially for the prediction of macrosomia. This study aimed to identify a novel predictive methodology to improve the prediction of high-risk macrosomia. METHODS: Clinical information was collected from 3730 patients. The association between the ISFHAC (index of the SFH algorithm multiplied by the square of AC) and foetal weight was determined and validated. A new index, the ISFHAC, was evaluated by area under the curve (AUC) analysis. RESULTS: A total of 1087 GDM and 657 normal singleton pregnancies were analysed. The ISFHAC was positively correlated with foetal weight in GDM pregnancies and normal pregnancies (NPs). The AUCs of the ISFHAC were 0.815 in the GDM group and 0.804 in the NP group, which were higher than those of BMI, SFH, AC and GA. The ISFHAC cut-off points were 41.7 and 37 in the GDM and NP groups, respectively. The sensitivity values for the prediction of macrosomia with high ISFHAC values were 75.9 and 81.3% in the GDM and NP groups, respectively, which were higher than those with BMI. Regarding the validation data, the sensitivity values for prediction with high ISFHAC values were 78.9% (559 GDM pregnancies) and 78.3% (1427 NPs). CONCLUSIONS: The ISFHAC can be regarded as a new predictor of and risk factor for macrosomia in GDM pregnancy and NP.
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Abdome/anatomia & histologia , Diabetes Gestacional , Macrossomia Fetal/diagnóstico , Sínfise Pubiana/anatomia & histologia , Útero/anatomia & histologia , Adolescente , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Tamanho do Órgão , Valor Preditivo dos Testes , Gravidez , Estudos Prospectivos , Adulto JovemRESUMO
Three-dimensional topological insulators (3D TIs) represent states of quantum matters in which surface states are protected by time-reversal symmetry and an inversion occurs between bulk conduction and valence bands. However, the bulk-band inversion, which is intimately tied to the topologically nontrivial nature of 3D Tis, has rarely been investigated by experiments. Besides, 3D massive Dirac fermions with nearly linear band dispersions were seldom observed in TIs. Recently, a van der Waals crystal, ZrTe5, was theoretically predicted to be a TI. Here, we report an infrared transmission study of a high-mobility [â¼33,000 cm2/(V â s)] multilayer ZrTe5 flake at magnetic fields (B) up to 35 T. Our observation of a linear relationship between the zero-magnetic-field optical absorption and the photon energy, a bandgap of â¼10 meV and a [Formula: see text] dependence of the Landau level (LL) transition energies at low magnetic fields demonstrates 3D massive Dirac fermions with nearly linear band dispersions in this system. More importantly, the reemergence of the intra-LL transitions at magnetic fields higher than 17 T reveals the energy cross between the two zeroth LLs, which reflects the inversion between the bulk conduction and valence bands. Our results not only provide spectroscopic evidence for the TI state in ZrTe5 but also open up a new avenue for fundamental studies of Dirac fermions in van der Waals materials.
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BACKGROUND: Proprotein convertase subtilisin/kexin type 9 (PCSK9), a major regulator of cholesterol homeostasis, is associated with glucose metabolism. Liraglutide, a glucagon-like peptide-1 receptor agonist, can increase insulin secretion in a glucose-dependent manner and lower blood glucose. We aimed to investigate the relationship between liraglutide and PCSK9. METHODS: At the cellular level, the expressions of PCSK9 and hepatocyte nuclear factor 1 alpha (HNF1α) protein in HepG2 cells stimulated by liraglutide was examined using Western blot. Seven-week old db/db mice and wild type (WT) mice were administered either liraglutide (200 µg/kg) or equivoluminal saline subcutaneously, twice daily for 7 weeks. Fasting glucose level, food intake and body weight were measured every week. After the 7-week treatment, the blood was collected for lipid and PCSK9 levels detection and the liver was removed from the mice for oil red O staining, immunohistochemical analysis, immunofluorescence test and Western bolt. RESULTS: Firstly, liraglutide suppressed both PCSK9 and HNF1α expression in HepG2 cells in a time and concentration dependent manner. Secondly, liraglutide induced weight loss in WT and db/db mice, decreased serum PCSK9, glucose and lipid levels and improved hepatic accumulation in db/db but not WT mice. Thirdly, liraglutide reduced both hepatic PCSK9 and low-density lipoprotein receptor (LDLR) expression with a decrease in HNF1α in db/db mice but not in WT mice. CONCLUSIONS: Liraglutide suppressed PCSK9 expression through HNF1α-dependent mechanism in HepG2 cells and db/db mice, and decreased LDLR possibly via PCSK9-independent pathways in db/db mice.
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Diabetes Mellitus/tratamento farmacológico , Fator 1-alfa Nuclear de Hepatócito/metabolismo , Hepatócitos/efeitos dos fármacos , Hipoglicemiantes/farmacologia , Incretinas/farmacologia , Liraglutida/farmacologia , Pró-Proteína Convertase 9/metabolismo , Receptores de LDL/efeitos dos fármacos , Animais , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Diabetes Mellitus/sangue , Diabetes Mellitus/enzimologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Regulação para Baixo , Células Hep G2 , Hepatócitos/enzimologia , Humanos , Lipídeos/sangue , Masculino , Camundongos , Receptores de LDL/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de TempoRESUMO
We report infrared studies of AFe_{2}As_{2} (A=Ba, Sr), two representative parent compounds of iron-arsenide superconductors, at magnetic fields (B) up to 17.5 T. Optical transitions between Landau levels (LLs) were observed in the antiferromagnetic states of these two parent compounds. Our observation of a sqrt[B] dependence of the LL transition energies, the zero-energy intercepts at B=0 T under the linear extrapolations of the transition energies and the energy ratio (â¼2.4) between the observed LL transitions, combined with the linear band dispersions in two-dimensional (2D) momentum space obtained by theoretical calculations, demonstrates the existence of massless Dirac fermions in the antiferromagnet BaFe_{2}As_{2}. More importantly, the observed dominance of the zeroth-LL-related absorption features and the calculated bands with extremely weak dispersions along the momentum direction k_{z} indicate that massless Dirac fermions in BaFe_{2}As_{2} are 2D. Furthermore, we find that the total substitution of the barium atoms in BaFe_{2}As_{2} by strontium atoms not only maintains 2D massless Dirac fermions in this system, but also enhances their Fermi velocity, which supports that the Dirac points in iron-arsenide parent compounds are topologically protected.
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BACKGROUND MicroRNA (miR) has been proved to be an important biomarker for tumors because it can regulate occurrence, progression, invasion, and metastasis of cancer. A previous study has shown the involvement of miR-503 in multiple gastrointestinal tumors. Its detailed role and immune regulatory function in esophagus carcinoma, however, remains unknown. This study thus investigated the effect of miR-503 in regulating growth, proliferation, and invasion of esophagus cancer and its influence on cytokine secretion. MATERIAL AND METHODS Esophagus carcinoma cell line EC9706 and normal esophageal epithelial cell line HEEC were transfected with miR-503 inhibitor. MTT assay was used to quantify the cell proliferation, and a Transwell chamber was used to evaluate cell invasion. Release of cytokines, including interleukin-2 (IL-2), IL-4, IL-10, and interferon-γ (IFN-γ), was measured by enzyme-linked immunosorbent assay (ELISA). RESULTS MiR-503 expression was significantly elevated in esophagus carcinoma cells (p<0.05). The specific inhibition of miR-503 expression remarkably suppressed proliferation and invasion of tumor cells. It can also down-regulated IL-2 and IFN-γ expression and facilitate secretion of IL-4 and IL-10 when compared to the control group (p<0.05 in all ceases). CONCLUSIONS The inhibition of miR-503 can effectively inhibit tumor progression and improve immune function, suggesting its potency as a novel drug target for esophagus cancer treatment.
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Neoplasias Esofágicas/genética , Neoplasias Esofágicas/terapia , MicroRNAs/antagonistas & inibidores , MicroRNAs/metabolismo , Carcinoma de Células Acinares/genética , Estudos de Casos e Controles , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Citocinas/imunologia , Citocinas/metabolismo , Regulação para Baixo/efeitos dos fármacos , Neoplasias Esofágicas/imunologia , Neoplasias Esofágicas/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Interferon gama/imunologia , Interferon gama/metabolismo , Interleucinas/imunologia , Interleucinas/metabolismo , MicroRNAs/genética , MicroRNAs/imunologia , Invasividade Neoplásica , Oligonucleotídeos/administração & dosagem , Oligonucleotídeos/genética , Distribuição Aleatória , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/metabolismoRESUMO
ErbB4 is an important member of ErbB subfamily of tyrosine kinases receptor with overexpression in several tumors; however its biological role in esophageal cancer is poorly understood till date. The main objective of this study was to examine whether miRNA-140-5p could target and control ErbB4 expression at transcriptional level. The ErbB4 expressions in different cell lines were evaluated by western blotting and luciferase assay. Moreover, cell proliferation, apoptosis, and cell invasion studies were investigated using MTT, flow cytometry, and transwell assays. miRNA-140-5p remarkably downregulated the ErbB4 expression in EC9706 and TE-1A cell lines. Furthermore, miRNA-140-5p transfected cell significantly controlled the cell proliferation and enhanced the apoptosis of multiple cells. Additionally, miRNA-140-5p had marked effect on the DNA synthesis and caspase 3/7 activity in comparison to control cells. Specifically, miRNA-140-5p inhibited/repressed the cancer cell invasion and migration in a sign to have important biological role in esophageal carcinomas. Taken together, miRNA-140-5p could act as a potential molecular target in ErbB4 overexpressing ESCC cell lines paving the way for effective esophageal cancer treatment.
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Neoplasias Esofágicas/genética , Neoplasias Esofágicas/terapia , MicroRNAs/biossíntese , Neoplasias de Células Escamosas/enzimologia , Neoplasias de Células Escamosas/terapia , RNA Neoplásico/biossíntese , Receptor ErbB-4/biossíntese , Apoptose/genética , Caspase 3/genética , Caspase 3/metabolismo , Caspase 7/genética , Caspase 7/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Neoplasias Esofágicas/enzimologia , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , Invasividade Neoplásica/genética , Neoplasias de Células Escamosas/genética , Neoplasias de Células Escamosas/patologia , RNA Neoplásico/genética , Receptor ErbB-4/genéticaRESUMO
Human midbrain dopaminergic progenitors (mDAPs) are one of the most representative cell types in both basic research and clinical applications. However, there are still many challenges for the preparation and quality control of mDAPs, such as the lack of standards. Therefore, the establishment of critical quality attributes and technical specifications for mDAPs is largely needed. "Human midbrain dopaminergic progenitor" jointly drafted and agreed upon by experts from the Chinese Society for Stem Cell Research, is the first guideline for human mDAPs in China. This standard specifies the technical requirements, test methods, inspection rules, instructions for usage, labelling requirements, packaging requirements, storage requirements, transportation requirements and waste disposal requirements for human mDAPs, which is applicable to the quality control for human mDAPs. It was originally released by the China Society for Cell Biology on 30 August 2022. We hope that the publication of this guideline will facilitate the institutional establishment, acceptance and execution of proper protocols, and accelerate the international standardization of human mDAPs for clinical development and therapeutic applications.
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Neurônios Dopaminérgicos , Mesencéfalo , Humanos , China , Neurônios Dopaminérgicos/metabolismoRESUMO
Accumulating evidence shows that microRNAs, functioning as either oncogenes or tumour suppressors by negatively regulating downstream target genes that are actively involved in tumour initiation and progression, may be promising biomarkers and therapy targets. Data mining through a microRNA chip database indicated that let-7c may be associated with tumour metastasis. Here, we confirmed that down-regulation of let-7c in primary cancer tissues was significantly associated with metastases, advanced TNM stages and poor survival of colorectal cancer patients. Moreover, ectopic expression of let-7c in a highly metastatic Lovo cell line remarkably suppressed cell migration and invasion in vitro by the down-regulation of K-RAS, MMP11 and PBX3, as well as tumour growth and metastases in vivo, whereas inhibition of let-7c in low-metastatic HT29 cells increased cell motility and invasion by the enhanced gene expression of K-RAS, MMP11 and PBX3. Interestingly, the luciferase reporters' activities with the 3'-UTRs of K-RAS, MMP11 and PBX3 were inhibited significantly by let-7c. Importantly, rescue experiments involving the over-expression of these genes without their 3'-UTRs completely reversed the effects of let-7c on tumour metastasis, both in vitro and in vivo. Finally, the levels of let-7c were inversely correlated with those of MMP11 and PBX3, but not with those of K-RAS. Taken together, these results demonstrate that let-7c, apart from its tumour growth suppression role, also functions as a tumour metastasis suppressor in colorectal cancer by directly destabilizing the mRNAs of MMP11 and PBX3 at least.
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Neoplasias Colorretais/metabolismo , Genes ras/fisiologia , Proteínas de Homeodomínio/metabolismo , Metaloproteinase 11 da Matriz/metabolismo , MicroRNAs/fisiologia , Proteínas Proto-Oncogênicas/metabolismo , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Regulação para Baixo , Feminino , Humanos , Masculino , MicroRNAs/antagonistas & inibidores , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Invasividade Neoplásica/fisiopatologia , Metástase Neoplásica , Prognóstico , RNA Mensageiro/metabolismoRESUMO
BACKGROUND: Gas-related complications present a potential risk during transoral endoscopic resection of upper gastrointestinal submucosal lesions. Therefore, the identification of risk factors associated with these complications is essential. AIM: To develop a nomogram to predict risk of gas-related complications following transoral endoscopic resection of the upper gastrointestinal submucosal lesions. METHODS: We collected patient data from the First Affiliated Hospital of the Army Medical University. Patients were randomly allocated to training and validation cohorts. Risk factors for gas-related complications were identified in the training cohort using univariate and multivariate analyses. We then constructed a nomogram and evaluated its predictive performance based on the area under the curve, decision curve analysis, and Hosmer-Lemeshow tests. RESULTS: Gas-related complications developed in 39 of 353 patients who underwent transoral endoscopy at our institution. Diabetes, lesion origin, surgical resection method, and surgical duration were incorporated into the final nomogram. The predictive capability of the nomogram was excellent, with area under the curve values of 0.841 and 0.906 for the training and validation cohorts, respectively. CONCLUSION: The ability of our four-variable nomogram to efficiently predict gas-related complications during transoral endoscopic resection enhanced postoperative assessments and surgical outcomes.
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In this paper, we reported a coumarin-based fluorescent probe for selective detection of H2O2/SO2 derivatives via ICT process. To the best of our knowledge, it was few reported with the same probe to enable visual detection of H2O2/SO2 derivatives in vivo and in vitro. H2O2 and SO32- were selectively sensed over other analytes, and the probe displayed 20-fold and 220-fold relative fluorescence intensity respectively, as well as the good linear relationship and the excellent detection limits of 2.7 * 103 nM and 19.3 nM. Furthermore, the probe was successfully used for fluorescence imaging of the HeLa cells and the mice to monitor exogenous and endogenous H2O2 and SO32-, suggesting its potential biomedical application for investigation and detection the intermediate indicator of oxidative stress in vitro and in vivo.
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Corantes Fluorescentes , Peróxido de Hidrogênio , Humanos , Camundongos , Animais , Células HeLa , Limite de Detecção , Imagem ÓpticaRESUMO
BACKGROUND: Neurofilament light chain (NfL) is a novel biomarker for the assessment of neurological function after cardiac arrest (CA). Although meta-analysis has confirmed its predictive value, it has not conducted a more detailed analysis of its research. We conducted a meta-analysis to evaluate the relationship between serum NfL level and neurological prognosis in patients with spontaneous circulation recovery after CA, and subgroup analysis was conducted according to sample collection time, time to assess neurological function, study design, whether TTM was received, the method of specimen determination, and the presence of neurological disease in patients. To analyze the influence of these factors on the predictive value of serum NfL. METHODS: Published Cochrane reviews and an updated, extended search of MEDLINE, Cochrane Library, Embase, Scopus, ClinicalKey, CINAHL, and Web of Science for relevant studies until March 2022 were assessed through inclusion and exclusion criteria. The standard mean difference and 95% confidence interval were calculated using the random-effects model or fixed-effects model to assess the association between one variable factor NfL level and the outcome of CA patients. Subgroup analysis according to sample collection time was performed. The prognosis analysis and publication bias were also assessed using Egger's and Begg's tests. RESULTS: Among 1209 related articles for screening, 6 studies (1360 patients) met the inclusion criteria and were selected for meta-analysis. The level of serum NfL in the good prognosis group (CPC1-2, CPC: cerebral performance category score) was significantly lower than that in the poor prognosis group (CPC3-5)SMD(standardized mean difference) = 0.553, 95%CI(confidence interval) = 0.418-0.687, I2 = 65.5% P<0.05). And this relationship also exists at each sampling time point (NfL specimens were collected on admission: SMD:0.48,95%CI:0.24-0.73; Samples were collected 24 hours after CA: SMD:0.60,95%CI:0.32-0.88;Specimens were obtained 48 hours after CA: SMD:0.51, 95%CI:0.18-0.85;Specimens were obtained 72 hours after CA: SMD:0.59, 95%CI:0.38-0.81). CONCLUSION: NfL may play a potential neuroprognostication role in postcardiac arrest patients with spontaneous circulation, regardless of when the sample was collected after CA.
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Bibliotecas , Parada Cardíaca Extra-Hospitalar , Humanos , Filamentos Intermediários , Biblioteca Gênica , Aplicação da LeiRESUMO
We here tested the potential activity and the underlying mechanisms of neuroligin-3 (NLGN3) against ischemia-reperfusion-induced neuronal cell injury. In SH-SY5Y neuronal cells and primary murine cortical neurons, NLGN3 activated Akt-mTOR and Erk signalings, and inhibited oxygen and glucose deprivation (OGD)/re-oxygenation (OGD/R)-induced cytotoxicity. Akt activation was required for NLGN3-induced neuroprotection. Gαi1/3 mediated NLGN3-induced downstream signaling activation. NLGN3-induced Akt-S6K1 activation was largely inhibited by Gαi1/3 silencing or knockout. Significantly, NLGN3-induced neuroprotection against OGD/R was almost abolished by Gαi1/3 silencing or knockout. In vivo, the middle cerebral artery occlusion (MCAO) procedure induced NLGN3 cleavage and secretion, and increased its expression and Akt activation in mouse brain tissues. ADAM10 (A Disintegrin and Metalloproteinase 10) inhibition blocked MCAO-induced NLGN3 cleavage and secretion, exacerbating ischemic brain injury in mice. Neuronal silencing of NLGN3 or Gαi1/3 in mice also inhibited Akt activation and intensified MCAO-induced ischemic brain injury. Conversely, neuronal overexpression of NLGN3 increased Akt activation and alleviated MCAO-induced ischemic brain injury. Together, NLGN3 activates Gαi1/3-Akt signaling to protect neuronal cells from ischemia-reperfusion injury.
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Lesões Encefálicas , Isquemia Encefálica , Neuroblastoma , Traumatismo por Reperfusão , Animais , Humanos , Camundongos , Lesões Encefálicas/metabolismo , Isquemia Encefálica/metabolismo , Infarto da Artéria Cerebral Média/metabolismo , Neuroblastoma/metabolismo , Neurônios/metabolismo , Oxigênio/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Traumatismo por Reperfusão/metabolismoRESUMO
Tripterygium wilfordii Hook F. is a well-known but poisonous traditional Chinese medicine used for treating a wide variety of inflammatory and autoimmune disorders. Celastrol, a quinone methyl triterpenoid compound and a representative component of T. wilfordii Hook F., shows a variety of pharmacological activities, such as anti-inflammatory and antitumor activities. Here, we investigated the antineuropathic pain (NP) effect of celastrol and its potential mechanisms. Rats with chronic constrictive injury (CCI)-induced NP were used to evaluate the analgesic effect of celastrol. Gabapentin was used as a reference compound (positive control). The results showed that gabapentin (100 mg/kg, i.p.) and multiple doses of celastrol (0.5, 1 and 2 mg/kg, i.p.) increased the threshold of mechanical and thermal pain in the rats with NP. Western blot results showed that celastrol significantly inhibited the activation of microglia and astrocytes in the spinal cord of rats with NP. Additionally, the levels of the proinflammatory cytokines tumor necrosis factor α (TNF-α), interleukin 1ß and interleukin 6, detected by ELISA in the spinal cord of the rats with NP, were significantly inhibited by celastrol. Furthermore, celastrol treatment dramatically inhibited the expression of the TLR4/NF-κB signaling pathway in the spinal cord. Taken together, our findings suggested that celastrol could attenuate mechanical and thermal pain in CCI-induced NP, and this protection might be attributed to inhibiting the TLR4/NF-κB signaling pathway and exerting anti-inflammatory effects in the spinal cord.
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NF-kappa B , Neuralgia , Animais , NF-kappa B/metabolismo , Neuralgia/tratamento farmacológico , Triterpenos Pentacíclicos , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Medula Espinal/metabolismo , Receptor 4 Toll-Like/genéticaRESUMO
A van der Waals material, MoTe2 with a monoclinic 1T' crystal structure is a candidate for 3D second-order topological insulators (SOTIs) hosting gapless hinge states and insulating surface states. However, due to the temperature-induced structural phase transition, the monoclinic 1T' structure of MoTe2 is transformed into the orthorhombic Td structure as the temperature is lowered, which hinders the experimental verification and electronic applications of the predicted SOTI state at low temperatures. Here, systematic Raman spectroscopy studies of the exfoliated MoTe2 thin flakes with variable thicknesses at different temperatures, are presented. As a spectroscopic signature of the orthorhombic Td structure of MoTe2 , the out-of-plane vibration mode D at ≈ 125 cm-1 is always visible below a certain temperature in the multilayer flakes thicker than ≈ 27.7 nm, but vanishes in the temperature range from 80 to 320 K when the flake thickness becomes lower than ≈ 19.5 nm. The absence of the out-of-plane vibration mode D in the Raman spectra here demonstrates not only the disappearance of the monoclinic-to-orthorhombic phase transition but also the persistence of the monoclinic 1T' structure in the MoTe2 thin flakes thinner than ≈ 19.5 nm at low temperatures down to 80 K, which may be caused by the high enough density of the holes introduced during the gold-enhanced exfoliation process and exposure to air. The MoTe2 thin flakes with the low-temperature monoclinic 1T' structure provide a material platform for realizing SOTI states in van der Waals materials at low temperatures, which paves the way for developing a new generation of electronic devices based on SOTIs.
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Traumatic brain injury (TBI) is a serious global public health problem. Survivors of TBI often suffer from long-term disability, which puts a heavy burden on society and families. Unfortunately, up to now, there is no efficacious treatment for TBI patients in clinical practice. As a reducing gas, hydrogen has been shown to be neuroprotective in multiple cerebral disease models; however, its efficacy in TBI remains controversial. In this review, we will focus on the results of hydrogen in experimental TBI, elaborate the potential mechanisms, and put forward for future researches based on our current understanding and views.
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Lesões Encefálicas Traumáticas , Hidrogênio , HumanosRESUMO
Mesenchymal stem cells (MSCs) have become a promising therapeutic strategy for scleroderma. Exosomes derived from MSCs (MSC-exosomes) possess functional properties similar to those of their source cells. In this study, we aimed to explore the potential role of MSC-exosomes in the treatment of scleroderma. MSC-exosomes were isolated from human umbilical cords through ultracentrifugation and characterized. An experimental fibrosis model was established in BALB/c mice by a subcutaneous injection of bleomycin, followed by treatment with MSC-exosomes or MSC infusions once a week for a total of four doses. Using hematoxylin and eosin and Masson's trichrome staining and immunohistochemistry, hydroxyproline content, and quantitative real-time polymerase chain reaction analyses, we investigated the effects of MSC-exosomes on dermal fibrosis and explored the underlying mechanism. MSC-exosome treatment restored the dermal architecture, reduced dermal thickness, and partially increased subcutaneous adipose tissue thickness. In addition, MSC-exosomes inhibited the expression of collagen (COL)-I, COL-III, and α-smooth muscle actin. The transforming growth factor (TGF)-ß/Smad signaling pathway was also suppressed in MSC-exosome-treated mice. Taken together, our results suggest that MSC-exosomes can attenuate myofibroblast activation and collagen deposition in dermal fibrosis by downregulating the TGF-ß/Smad signaling pathway. Therefore, the use of MSC-exosomes may be a potential therapeutic approach for the treatment of scleroderma.
Assuntos
Exossomos , Células-Tronco Mesenquimais , Animais , Bleomicina , Modelos Animais de Doenças , Exossomos/metabolismo , Fibrose , Camundongos , Camundongos Endogâmicos BALB CRESUMO
BACKGROUND: The combination of inhibitory and facilitatory repetitive transcranial magnetic stimulation (rTMS) can improve motor function of stroke patients with undefined mechanism. It has been demonstrated that rTMS exhibits a neuro-modulatory effect by regulating the major inhibitory neurotransmitter γ-aminobutyric acid (GABA) in other diseases. OBJECTIVES: To evaluate the effect of combined inhibitory and facilitatory rTMS on GABA in the primary motor cortex (M1) for treating motor dysfunction after acute ischemic stroke. METHODS: 44 ischemic stroke patients with motor dysfunction were randomly divided into two groups. The treatment group was stimulated with 10âHz rTMS at the ipsilesional M1 and 1âHz rTMS at the contralesional M1. The sham group received bilateral sham stimulation at the motor cortices. The GABA level in the bilateral M1 was measured by proton magnetic resonance spectroscopy (1H-MRS) at 24 hours before and after rTMS stimulation. Motor function was measured using the Fugl-Meyer Assessment (FMA). The clinical assessments were performed before and after rTMS and after 3 months. RESULTS: The treatment group exhibited a greater improvement in motor function 24 hours after rTMS compared to the sham group. The increased improvement in motor function lasted for at least 3 months after treatment. Following 4 weeks of rTMS, the GABA level in the ipsilesional M1 of the treatment group was significantly decreased compared to the sham group. Furthermore, the change of FMA score for motor function was negatively correlated to the change of the GABA:Cr ratio. Finally, the effect of rTMS on motor function outcome was partially mediated by GABA level change in response to the treatment (27.7%). CONCLUSIONS: Combining inhibitory and facilitatory rTMS can decrease the GABA level in M1, which is correlated to the improvement of motor function. Thus, the GABA level in M1 may be a potential biomarker for treatment strategy decisions regarding rTMS neuromodulatory interventions.
Assuntos
AVC Isquêmico , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Recuperação de Função Fisiológica/fisiologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/terapia , Reabilitação do Acidente Vascular Cerebral/métodos , Estimulação Magnética Transcraniana/métodos , Resultado do Tratamento , Ácido gama-AminobutíricoRESUMO
The interplay between electronic correlations and topological protection may offer a rich avenue for discovering emergent quantum phenomena in condensed matter. However, electronic correlations have so far been little investigated in Weyl semimetals (WSMs) by experiments. Here, we report a combined optical spectroscopy and theoretical calculation study on the strength and effect of electronic correlations in a magnet Co3Sn2S2. The electronic kinetic energy estimated from our optical data is about half of that obtained from single-particle ab initio calculations in the ferromagnetic ground state, which indicates intermediate-strength electronic correlations in this system. Furthermore, comparing the energy and side-slope ratios between the interband-transition peaks at high energies in the experimental and single-particle-calculation-derived optical conductivity spectra with the bandwidth-renormalization factors obtained by many-body calculations enables us to estimate the Coulomb-interaction strength (U â¼ 4 eV) in Co3Sn2S2. Besides, a sharp experimental optical conductivity peak at low energy, which is absent in the single-particle-calculation-derived spectrum but is consistent with the optical conductivity peaks obtained by many-body calculations with U â¼ 4 eV, indicates that an electronic band connecting the two Weyl cones is flattened by electronic correlations and emerges near the Fermi energy in Co3Sn2S2. Our work paves the way for exploring flat-band-generated quantum phenomena in WSMs.