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1.
Am Surg ; : 31348241241730, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38549438

RESUMO

OBJECTIVE: The primary objective was to construct a high-performing prognostic risk model to accurately forecast the prognosis of patients diagnosed with intrahepatic cholangiocarcinoma (iCCA). METHODS: We retrospectively collected clinical data from the MSK database on 125 patients diagnosed with iCCA. Random sampling was utilized to divide patients into a training set and a validation set, maintaining a ratio of 7:3. Univariate and multivariate Cox proportional hazards regression models were utilized to identify independent prognostic factors influencing OS. Based on these independent factors, a model nomogram was established. The performance of the prognostic prediction models was assessed through calibration curves and C-index calculations. The Kaplan-Meier method was used to plot survival curves. Time-dependent ROC curve was used to evaluate the accuracy of the model. RESULTS: A nomogram was developed, incorporating hepatitis C, CA19, tumor extent, tumor size, LVI, positive lymph nodes, and TMB as predictive factors. The C-index for the training set was .78 and the validation set was .68. Using the riskscore derived from the nomogram, patients were stratified into high- and low-risk groups. The high-risk group exhibited considerably lower OS and RFS compared to the low-risk group in the training set (P < .05). However, no significant difference was detected in RFS among different risk groups in the validation set (P > .05). The AUC for 1-year, 3-year, and 5-year survival was .89, .69, and .69, respectively. CONCLUSION: We successfully developed and validated a prognostic nomogram for iCCA, demonstrating its excellent accuracy in predicting patient outcomes and providing clinicians with a potential prognostic tool.

2.
Drug Des Devel Ther ; 18: 443-452, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38370564

RESUMO

Purpose: Dexmedetomidine (Dex) is a potent and highly selective α2-adrenergic receptor agonist. Within an appropriate dose range, Dex can effectively attenuate the surgical stress response, provide intraoperative hemodynamic stability, and improve the patient recovery quality. High-dose Dex can delay patient awakening from anesthesia and increase the incidence of bradycardia. This randomized controlled trial aimed to investigate the effects of low-dose intravenous Dex premedication in patients undergoing laparoscopic cholecystectomy (LC). Material and Methods: In total, 100 patients undergoing LC were equally randomized into Group C (premedication with saline) and Group D (premedication with 0.5 µg/kg Dex). The patients were premedicated with saline or Dex, depending on the group, before anesthesia induction. Following this, anesthesia induction and endotracheal intubation was performed, and anesthesia was maintained during surgery. Following the completion of the surgery, the patients were transferred the post-anesthesia care unit (PACU) and stayed there until they met the PACU discharge criteria. The hemodynamic parameters, consumption of anesthetics, surgical duration, postoperative awakening time, extubation time, postoperative pain, and complications were recorded. Results: No significant differences were observed in the heart rate (HR) and mean arterial pressure (MAP) between the two groups before premedication (P>0.05). The MAP and HR immediately after endotracheal intubation and immediately after extubation were significantly lower in Group D than in Group C (P<0.05 for both). The incidence of bradycardia was significantly higher in Group D than in Group C (P<0.05), while atropine was used in neither group. Propofol and remifentanil consumption was significantly lower in Group D than in Group C (P<0.05). The postoperative awakening and extubation times were significantly shorter in Group D than in Group C (P<0.05). The postoperative visual analog scale scores for pain and incidence of nausea, vomiting, and cough were significantly lower in Group D than in Group C (P<0.05 for all). Conclusion: Our data suggest that premedication with dexmedetomidine (0.5 µg/kg) before general anesthesia induction can effectively attenuate intraoperative stress response and postoperative pain, maintain perioperative hemodynamic stability, and decrease the incidence of adverse events, which might be an effective and safe anesthetic protocol during LC worthy of further clinical application.


Assuntos
Colecistectomia Laparoscópica , Dexmedetomidina , Humanos , Bradicardia/induzido quimicamente , Estudos Prospectivos , Anestesia Geral , Dor Pós-Operatória/tratamento farmacológico , Pré-Medicação/métodos , Método Duplo-Cego
3.
Immunity ; 56(11): 2508-2522.e6, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37848037

RESUMO

Cyclic guanosine monophosphate (GMP)-AMP (cGAMP) synthase (cGAS) is a universal double-stranded DNA (dsDNA) sensor that recognizes foreign and self-DNA in the cytoplasm and initiates innate immune responses and has been implicated in various infectious and non-infectious contexts. cGAS binds to the backbone of dsDNA and generates the second messenger, cGAMP, which activates the stimulator of interferon genes (STING). Here, we show that the endogenous polyamines spermine and spermidine attenuated cGAS activity and innate immune responses. Mechanistically, spermine and spermidine induced the transition of B-form DNA to Z-form DNA (Z-DNA), thereby decreasing its binding affinity with cGAS. Spermidine/spermine N1-acetyltransferase 1 (SAT1), the rate-limiting enzyme in polyamine catabolism that decreases the cellular concentrations of spermine and spermidine, enhanced cGAS activation by inhibiting cellular Z-DNA accumulation; SAT1 deficiency promoted herpes simplex virus 1 (HSV-1) replication in vivo. The results indicate that spermine and spermidine induce dsDNA to adopt the Z-form conformation and that SAT1-mediated polyamine metabolism orchestrates cGAS activity.


Assuntos
DNA de Forma B , DNA Forma Z , Espermina/metabolismo , Espermidina/metabolismo , DNA/metabolismo , Nucleotidiltransferases/metabolismo , Poliaminas/metabolismo , Imunidade Inata/genética
4.
J Clin Invest ; 133(20)2023 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-37651190

RESUMO

The NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3) inflammasome is a crucial component of the innate immune system that initiates inflammatory responses. Posttranslational modifications (PTMs) of NLRP3, including ubiquitination and phosphorylation, control inflammasome activation and determine the intensity of inflammation. However, the role of other PTMs in controlling NLRP3 inflammasome activation remains unclear. This study found that TLR priming induced NLRP3 ISGylation (a type of PTM in which ISG15 covalently binds to the target protein) to stabilize the NLRP3 protein. Viral infection, represented by SARS-COV-2 infection, and type I IFNs induced expression of ISG15 and the predominant E3 ISGylation ligases HECT domain- and RCC1-like domain-containing proteins (HERCs; HERC5 in humans and HERC6 in mice). HERCs promoted NLRP3 ISGylation and inhibited K48-linked ubiquitination and proteasomal degradation, resulting in the enhancement of NLRP3 inflammasome activation. Concordantly, Herc6 deficiency ameliorated NLRP3-dependent inflammation as well as hyperinflammation caused by viral infection. The results illustrate the mechanism by which type I IFNs responses control inflammasome activation and viral infection-induced aberrant NLRP3 activation. This work identifies ISGylation as a PTM of NLRP3, revealing a priming target that modulates NLRP3-dependent immunopathology.


Assuntos
COVID-19 , Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Processamento de Proteína Pós-Traducional , Animais , Humanos , Camundongos , COVID-19/metabolismo , Inflamação , Camundongos Endogâmicos NOD , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , SARS-CoV-2/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
5.
Drug Des Devel Ther ; 17: 1347-1356, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37168489

RESUMO

Purpose: Patients with obesity are more susceptible to hypoxemia. Anesthetic management for patients with obesity undergoing painless gastroscopy presents a severe challenge for anesthesiologists. Esketamine is a NMDA antagonist that has been proven to be beneficial for ameliorating respiratory depression owing to its sympathomimetic effect; however, there are no relevant reports on its use in patients with obesity. We designed a randomized controlled trial to evaluate whether esketamine can be the ideal adjuvant to propofol sedation in patients with obesity undergoing painless gastroscopy. Patients and Methods: A total of 104 patients with obesity undergoing painless gastroscopy were randomly divided into group C (propofol+saline) and group S (propofol+esketamine 0.25 mg/kg). Anesthesia was induced by 2 mg/kg propofol with saline or esketamine. The consumption of propofol, hemodynamic parameters, duration of procedure, induction time, postoperative awakening time, and orientation recovery time were recorded. Adverse events and satisfaction scores were also recorded. Results: Propofol consumption was 274.4±22.6 mg and 201.3±16.6 mg in groups C and S, respectively. The induction time of groups C and S were 25.4±2.3 s and 17.8±1.9 s, respectively. The postoperative awakening times of groups C and S were 6.2±1.1 min and 4.8±1.3 min, respectively. Hemodynamic parameters were more stable in group S than in group C. The incidence of adverse events such as injection pain, hypoxemia, hypotension, bradycardia, choking, and body movement were significantly lower in group S. The satisfaction scores of the endoscopist and anesthesiologist were (4.58±0.49 vs 3.71±0.83) and (4.75±0.44 vs 3.33±0.92), respectively. Conclusion: The combination of propofol and esketamine (0.25 mg/kg) improves the safety and reduces the incidence of adverse events in patients with obesity during painless gastroscopy. Thus, this method is worthy of clinical application. Clinical Trials Registration: ChiCTR 2200062547.


Assuntos
Propofol , Humanos , Propofol/efeitos adversos , Gastroscopia/efeitos adversos , Gastroscopia/métodos , Estudos Prospectivos , Hipóxia/tratamento farmacológico , Obesidade/tratamento farmacológico , Obesidade/cirurgia , Obesidade/induzido quimicamente
6.
Front Surg ; 10: 1116523, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36860939

RESUMO

Background: Non-intubated video-assisted thoracoscopic surgery (NIVATS) has been increasingly applied worldwide owing to its benefits of enhanced recovery after surgery (ERAS). Anesthetic management for patients with asthma should focus on minimizing airway stimulation. Case description: A 23-year-old male patient with a history of asthma was diagnosed with left-sided spontaneous pneumothorax. The patient then underwent left-sided NIVATS bullectomy under general anesthesia with preserved spontaneous breathing. Left thoracic paravertebral nerve block (TPVB) with an injection of 0.375% ropivacaine (30 ml) was performed in the 6th paravertebral space under ultrasound guidance. Anesthesia induction commenced until the cold sensation in the surgical area had disappeared. General anesthesia was induced by midazolam, penehyclidine hydrochloride, esketamine, and propofol and then maintained using propofol and esketamine. Surgery commenced after the patient was positioned in the right lateral recumbency. The collapse of the left lung was satisfactory, and the operative field was ensured after artificial pneumothorax. The surgical procedure was uneventful, intraoperative arterial blood gases were within normal ranges, and vital signs were stable. The patient awakened rapidly without any adverse reactions at the end of the surgery and was then transferred to the ward. During the postoperative follow-up, the patient experienced mild pain 48 h after surgery. The patient was discharged from the hospital 2 days postoperatively and developed no nausea, vomiting, or any other complications. Conclusion: The present case suggests the feasibility of TPVB in combination with non-opioid anesthetics to provide high-quality anesthesia in patients undergoing NIVATS bullectomy.

8.
Nat Commun ; 12(1): 4794, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-34373456

RESUMO

The cellular NLRP3 protein level is crucial for assembly and activation of the NLRP3 inflammasome. Various posttranslational modifications (PTMs), including phosphorylation and ubiquitination, control NLRP3 protein degradation and inflammasome activation; however, the function of small ubiquitin-like modifier (SUMO) modification (called SUMOylation) in controlling NLRP3 stability and subsequent inflammasome activation is unclear. Here, we show that the E3 SUMO ligase tripartite motif-containing protein 28 (TRIM28) is an enhancer of NLRP3 inflammasome activation by facilitating NLRP3 expression. TRIM28 binds NLRP3, promotes SUMO1, SUMO2 and SUMO3 modification of NLRP3, and thereby inhibits NLRP3 ubiquitination and proteasomal degradation. Concordantly, Trim28 deficiency attenuates NLRP3 inflammasome activation both in vitro and in vivo. These data identify a mechanism by which SUMOylation controls the cellular NLRP3 level and inflammasome activation, and reveal correlations and interactions of NLRP3 SUMOylation and ubiquitination during inflammasome activation.


Assuntos
Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Sumoilação/fisiologia , Proteína 28 com Motivo Tripartido/metabolismo , Animais , Feminino , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Fosforilação , Processamento de Proteína Pós-Traducional , Proteólise , Proteína SUMO-1/metabolismo , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/metabolismo , Sumoilação/genética , Proteína 28 com Motivo Tripartido/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Ubiquitinas/metabolismo
9.
Org Lett ; 23(9): 3746-3750, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33884872

RESUMO

Derived from a Pd-catalyzed oxidative C-H/C-H coupling reaction, two giant imidazole-based [60]tetradecaphyrins adopting stable figure-eight geometry together with one [30]heptaphyrin are obtained by [5 + 2] MacDonald condensations in one pot. The directional imidazole is believed to play a vital role for the diverse cyclization and conformation stabilization.

10.
Angew Chem Int Ed Engl ; 60(7): 3493-3497, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33084206

RESUMO

Disclosed here is a palladium-catalyzed direct [4+1] spiroannulation of ortho-C-H bonds of naphthols with cyclic diaryliodonium salts to construct spirofluorenyl naphthalenones (SFNP) under mild reaction conditions. This spiroannulation directly transforms the hydroxy group into a carbonyl group, and also tolerates reactive functional groups such as the halo groups, which provide an opportunity to rapidly assemble structurally new thermally activated delayed fluorescent (TADF) materials that feature a carbonyl group with an adjacent spirofluorenyl unit as the acceptor. As an illustrated example, the OLED device utilizing the assembled DMAC-SFNP as the host material exhibits a low turn-on voltage of 2.5 V and an ultra-high external quantum efficiency of 32.2 %. This work provides inspiration for structurally new TADF materials, and also displays the potential of C-H activation as a synthetic strategy for the innovation of optoelectronic materials.

11.
Chem Sci ; 10(30): 7274-7280, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31588297

RESUMO

Here we present a divergent synthesis of brand-new types of meso-N/O-heteroarene-fused (quinoidal) porphyrins through Rh-catalyzed ß-C-H activation/annulation of 5,15-dioxoporphyrins and dioxime derivatives with alkynes, in which the synthetic disconnections are difficult to access through the commonly used intramolecular cyclization strategy. Using the O-methyl oxime as a traceless oxidizing directing group, the meso-N-embedded pyridine-fused anti-quinoidal porphyrin 3 and pyridinium-fused cation 4 are formed with controllable chemoselectivity and complete anti-selectivity. Replacing the exocyclic oxime with a carbonyl group delivers the pyran-fused porphyrin 5, achieving structural conversion from a quinoidal conformation to a stable porphyrin macrocycle. Further oxidation of the expanded dimer 5ea gives the oxonium 6, which exhibits intense near-infrared (NIR) Q-bands up to 1300 nm. Theoretical studies demonstrate that the incorporation of a heteroatom at the meso-position enables more effective π-extension, resulting in a 22π aromatic (vs. 18π aromatic) character of pyran-fused porphyrins (syn/anti-5aa). Compared with the commercially available methylene blue (MB), syn-5al exhibits a better ability (Φ Δ = 0.61) to sensitize singlet oxygen (1O2) when irradiated with a 680 nm laser beam, and has potential as a photodynamic therapy (PDT) photosensitizer in the body's therapeutic window (650-900 nm).

12.
Org Lett ; 21(4): 1139-1143, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30714379

RESUMO

Disclosed herein is a highly efficient one-pot synthetic strategy to phenanthrone-type polyheterocycles via tandem rhodium(III)-catalyzed ortho-C-H heteroarylation of indolyl ketones and copper(II)-promoted intramolecular cyclization. This protocol enables a library of blue-emitting fluorophores with high quantum yields and narrow full widths at half-maximum to be rapidly built from readily available substrates, among of which 6,6,7,9,12-pentamethyl-6,12-dihydro-5 H-benzofuro[2,3- a]carbazol-5-one (4a) exhibits pure blue emission with Commission Internationale de I'Eclairage coordinates of (0.15, 0.09) and a high quantum yield of 85% in CH2Cl2 solution.

13.
Org Lett ; 20(22): 7071-7075, 2018 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-30362760

RESUMO

Fluorescent mitochondrial trackers with the dibenzo[ a, f]quinolizinium core are unprecedentedly synthesized by a one-pot protocol starting from commercially available benzaldehydes, anilines, and alkynes through a rhodium(III)-catalyzed cascade C-H N- and C-annulation reaction. Among them, 5g is the most prominent and exhibits high specificity, high efficiency at nanomolar level, superior photostability, and low cytotoxicity.


Assuntos
Alcinos/química , Compostos de Anilina/química , Benzaldeídos/química , Corantes Fluorescentes/síntese química , Mitocôndrias/ultraestrutura , Nanoestruturas/química , Quinolizinas/síntese química , Catálise , Técnicas de Cultura de Células , Estabilidade de Medicamentos , Corantes Fluorescentes/química , Células Hep G2 , Humanos , Ligação de Hidrogênio , Microscopia Confocal , Quinolizinas/química , Ródio/química , Sais
14.
Artigo em Inglês | MEDLINE | ID: mdl-29849718

RESUMO

To study the antitumor effect of Xihuang pill (XHP) on the number of Treg cells in the tumor microenvironment of 4T1 breast tumor-bearing mice by PI3K/AKT/AP-1 pathway, a mouse model was established. Flow cytometry (FCM) and immunohistochemistry (IHC) were used to detect the number of Treg cells in the tumor microenvironment; terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) was used to detect the apoptosis of Treg cells in tumor microenvironment. Quantitative real-time PCR (RT-qPCR) was used to detect the mRNA expression of PI3K, AKT, and AP-1 in Treg cells in tumor microenvironment; immunofluorescence (IF) and Western Blot (WB) were used to detect the protein expression of PI3K, AKT, and AP-1 in Treg cells in tumor microenvironment. Compared with the naive control group, the tumor weight in XHP groups decreased significantly (P < 0.05); FCM and IHC results showed that the number of Treg cells in the tumor microenvironment decreased with the dose of XHP groups (P < 0.05); TUNEL staining showed that the number of Treg cells in tumor microenvironment increased with the dose of XHP groups (P < 0.05); RT-qPCR results showed that the mRNA expression of PI3K and AKT in Treg cells decreased with the dose of XHP groups, while RNA expression of AP-1 increased with the dose of XHP groups (P < 0.05); IF and WB results showed that the protein expression of PI3K and AKT in Treg cells decreased with the dose of XHP groups and the protein expression of AP-1 increased with the dose of XHP groups (P < 0.05). The results suggested that XHP decreased the number of Treg cells via inhibiting PI3K and AKT expression and upregulating AP-1 expression in Treg cells and then promoting the apoptosis of Treg cells. Thus, XHP could improve the immunosuppressive state of tumor microenvironment and reverse the immune escape to inhibit tumor growth.

15.
Biomed Pharmacother ; 102: 1111-1119, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29710529

RESUMO

OBJECTIVE: To determine the role of the MEKK1/SEK1/JNK1/AP-1 pathway in the action of Xihuang pill (XHP) in reducing regulatory T (Treg) cell numbers in the tumor microenvironment in a 4T1 mouse breast cancer model, and to clarify the anti-tumor mechanism of XHP in breast cancer. METHODS: We established a mouse 4T1 breast cancer model. Model mice were administered XHP for 2 weeks, and tumor tissues were then removed, weighed, sliced, and homogenized. Treg cells in the tumor microenvironment were isolated by magnetic cell sorting and analyzed by immunohistochemistry and flow cytometry. Treg cell apoptosis was detected by TdT-mediated dUTP nick end labeling. mRNA expression levels of MEKK1, SEK1, JNK1, and AP-1 in Treg cells in the tumor microenvironment were detected by quantitative real-time PCR and their protein expression levels were detected by immunofluorescence staining and western blot. RESULTS: Tumor weights were significantly lower in the XHP groups compared with the untreated control group. The overall number of Treg cells in the tumor microenvironment decreased while the number of apoptotic Treg cells increased with increasing doses of XHP. mRNA and protein expression levels of MEKK1, SEK1, JNK1, and AP-1 in Treg cells in the tumor microenvironment increased with increasing doses of XHP. CONCLUSION: XHP might promote Treg cell apoptosis in the tumor microenvironment and further inhibit the tumor growth of 4T1 mouse breast cancer. The mechanism of XHP may be related to upregulation of gene and protein expression of MEKK1, SEK1, JNK1, and AP-1 in Treg cells in the tumor microenvironment.


Assuntos
Apoptose , Medicamentos de Ervas Chinesas/uso terapêutico , Sistema de Sinalização das MAP Quinases , Neoplasias Mamárias Animais/tratamento farmacológico , Neoplasias Mamárias Animais/patologia , Linfócitos T Reguladores/patologia , Microambiente Tumoral , Regulação para Cima , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Separação Celular , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/farmacologia , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Separação Imunomagnética , Contagem de Linfócitos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Neoplasias Mamárias Animais/enzimologia , Neoplasias Mamárias Animais/imunologia , Camundongos Endogâmicos BALB C , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Linfócitos T Reguladores/efeitos dos fármacos , Fator de Transcrição AP-1/metabolismo , Carga Tumoral/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
16.
Eur J Pharmacol ; 825: 75-84, 2018 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-29454608

RESUMO

Colon cancer is one of the deadliest cancers worldwide; abnormal microRNA expression is common during colon cancer development. The aim of the present study was to elucidate the role played by miR-185 in this context. We used quantitative real-time PCR (qRT-PCR) to measure miR-185 expression levels in colon cancer cell lines. The effects of miR-185 on colon cancer cell proliferation and invasion were assessed using the MTT, colony-forming, wound-healing, and transwell assays. A luciferase activity assay was used to confirm the target of miR-185. Our data showed that miR-185 was significantly down-regulated in colon cancer cells and colonic cancer tissues compared with NCM460 normal colonic epithelial cells and adjacent normal tissues. A functional analysis revealed that ectopic expression of miR-185 significantly inhibited colon cancer cell proliferation, colony formation, migration, and invasion. In addition, western blot, qRT-PCR, and luciferase assays confirmed in colon cancer cells that Wnt1 was a downstream target of miR-185, in turn suppressing ß-catenin-mediated signaling. In conclusion, we found that miR-185 inhibits colon cancer cell proliferation and invasion by targeting Wnt1, and that it serves as a tumor suppressor, indicating that the modulation of miR-185 levels may potentially be therapeutic in colon cancer patients.


Assuntos
Movimento Celular/genética , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , MicroRNAs/genética , Invasividade Neoplásica/genética , Proteína Wnt1/genética , Proliferação de Células/genética , Regulação para Baixo/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Células HCT116 , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Prognóstico , Transdução de Sinais/genética
17.
Brain Behav Immun ; 67: 118-129, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28823624

RESUMO

Mechanical brain injury (MBI) is a common neurotrosis disorder of the central nervous system (CNS), which has a higher mortality and disability. In the case of MBI, neurons death leads to loss of nerve function. To date, there was no satisfactory way to restore neural deficits caused by MBI. Endogenous neural stem cells (NSCs) can proliferate, differentiate and migrate to the lesions after brain injury, to replace and repair the damaged neural cells in the subventricular zone (SVZ), hippocampus and the regions of brain injury. In the present study, we first prepared a mouse model of cortical stab wound brain injury. Using the immunohistochemical and hematoxylin-eosin (H&E) staining method, we demonstrated that osthole (Ost), a natural coumarin derivative, was capable of promoting the proliferation of endogenous NSCs and improving neuronal restoration. Then, using the Morris water maze (MWM) test, we revealed that Ost significantly improved the learning and memory function in the MBI mice, increased the number of neurons in the regions of brain injury, hippocampus DG and CA3 regions. Additionally, we found that Ost up-regulated the expression of self-renewal genes Notch 1 and Hes 1. However, when Notch activity was blocked by the γ-secretase inhibitor DAPT, the expression of Notch 1 and Hes 1 mRNA was down-regulated, augmentation of NICD and Hes 1 protein was ameliorated, the proliferation-inducing effect of Ost was abolished. These results suggested that the effects of Ost were at least in part mediated by activation of Notch signaling pathway. Our findings support that Ost is a potential drug for treating MBI due to its neuronal restoration.


Assuntos
Lesões Encefálicas/metabolismo , Proliferação de Células/efeitos dos fármacos , Cumarínicos/administração & dosagem , Células-Tronco Neurais/fisiologia , Receptor Notch1/metabolismo , Fatores de Transcrição HES-1/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Lesões Encefálicas/complicações , Sobrevivência Celular , Disfunção Cognitiva/complicações , Aprendizagem em Labirinto , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/efeitos dos fármacos , RNA Mensageiro/metabolismo , Transdução de Sinais , Regulação para Cima
18.
PLoS Pathog ; 12(7): e1005762, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27427949

RESUMO

DNA methylation is an important epigenetic mechanism for phenotypic diversification in all forms of life. We previously described remarkable cell-to-cell heterogeneity in epigenetic pattern within a clonal population of Streptococcus pneumoniae, a leading human pathogen. We here report that the epigenetic diversity is caused by extensive DNA inversions among hsdSA, hsdSB, and hsdSC, three methyltransferase hsdS genes in the Spn556II type-I restriction modification (R-M) locus. Because hsdSA encodes the sequence recognition subunit of this type-I R-M DNA methyltransferase, these site-specific recombinations generate pneumococcal cells with variable HsdSA alleles and thereby diverse genome methylation patterns. Most importantly, the DNA methylation pattern specified by the HsdSA1 allele leads to the formation of opaque colonies, whereas the pneumococci lacking HsdSA1 produce transparent colonies. Furthermore, this HsdSA1-dependent phase variation requires intact DNA methylase activity encoded by hsdM in the Spn556II (renamed colony opacity determinant or cod) locus. Thus, the DNA inversion-driven ON/OFF switch of the hsdSA1 allele in the cod locus and resulting epigenetic switch dictate the phase variation between the opaque and transparent phenotypes. Phase variation has been well documented for its importance in pneumococcal carriage and invasive infection, but its molecular basis remains unclear. Our work has discovered a novel epigenetic cause for this significant pathobiology phenomenon in S. pneumoniae. Lastly, our findings broadly represents a significant advancement in our understanding of bacterial R-M systems and their potential in shaping epigenetic and phenotypic diversity of the prokaryotic organisms because similar site-specific recombination systems widely exist in many archaeal and bacterial species.


Assuntos
Proteínas de Bactérias/genética , Metilação de DNA/genética , Enzimas de Restrição-Modificação do DNA/genética , Epigênese Genética/genética , Streptococcus pneumoniae/genética , Animais , DNA Bacteriano/genética , Modelos Animais de Doenças , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Mutagênese Sítio-Dirigida , Fenótipo , Infecções Pneumocócicas/microbiologia , Reação em Cadeia da Polimerase
19.
Chem Commun (Camb) ; 52(37): 6253-6, 2016 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-27121366

RESUMO

In this work, we report novel Rh(iii)-catalyzed chemoselective functionalizations of tertiary aniline N-oxides with alkynes, including annulation via the sequential C(sp(2))-H and C(sp(3))-N activation for the formation of N-alkylindoles and an O-atom transfer (OAT) process for the synthesis of acetophenones.

20.
Toxicol Appl Pharmacol ; 289(3): 474-81, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26525509

RESUMO

Neurogenesis is the process by which neural stem cells (NSCs) proliferate and differentiate into neurons. This is diminished in several neurodegenerative disorders such as Alzheimer's disease (AD), which is characterized by the deposition of amyloid (A)ß peptides and neuronal loss. Stimulating NSCs to replace lost neurons is therefore a promising approach for AD treatment. Our previous study demonstrated that osthole modulates NSC proliferation and differentiation, and may reduce Aß protein expression in nerve cells. Here we investigated the mechanism underlying the effects of osthole on NSCs. We found that osthole enhances NSC proliferation and neuronal differentiation while suppressing apoptosis, effects that were exerted via activation of Wnt/ß-catenin signaling. These results provide evidence that osthole can potentially be used as a therapeutic agent in the treatment of AD and other neurodegenerative disorders.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Apoptose/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Cumarínicos/farmacologia , Neurogênese/efeitos dos fármacos , Via de Sinalização Wnt/efeitos dos fármacos , beta Catenina/metabolismo , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo
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