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1.
J Cardiothorac Vasc Anesth ; 38(2): 437-444, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38105126

RESUMO

OBJECTIVES: It is unknown whether there is a difference in pulmonary outcome in different intraoperative ventilation modes for cardiac surgery with cardiopulmonary bypass (CPB). The aim of this trial was to determine whether patients undergoing cardiac surgery with CPB could benefit from intraoperative optimal ventilation mode. DESIGN: This was a single-center, prospective, randomized controlled trial. SETTING: The study was conducted at a single-center tertiary-care hospital. PARTICIPANTS: A total of 1,364 adults undergoing cardiac surgery with CPB participated in this trial. INTERVENTIONS: Patients were assigned randomly (1:1:1) to receive 1 of 3 ventilation modes: volume-controlled ventilation (VCV), pressure-controlled ventilation (PCV), and pressure-controlled ventilation-volume guaranteed (PCV-VG). All arms of the study received the lung-protective ventilation strategy. MEASUREMENTS AND MAIN RESULTS: The primary outcome was a composite of postoperative pulmonary complications (PPCs) within the first 7 postoperative days. Pulmonary complications occurred in 168 of 455 patients (36.9%) in the PCV-VG group, 171 (37.6%) in the PCV group, and 182 (40.1%) in the VCV group, respectively. There was no statistical difference in the risk of overall pulmonary complications among groups (p = 0.585). There were no significant differences in the severity grade of PPCs within 7 days, postoperative ventilation duration, intensive care unit stay, postoperative hospital stay, or 30-day postoperative mortality. CONCLUSIONS: Among patients scheduled for cardiac surgery with CPB, intraoperative ventilation mode type did not affect the risk of postoperative pulmonary complications.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Respiração Artificial , Adulto , Humanos , Respiração Artificial/efeitos adversos , Estudos Prospectivos , Pulmão , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Ponte Cardiopulmonar/efeitos adversos , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia
2.
Mol Cell ; 59(2): 285-97, 2015 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-26118643

RESUMO

Many tumors become addicted to autophagy for survival, suggesting inhibition of autophagy as a potential broadly applicable cancer therapy. ULK1/Atg1 is the only serine/threonine kinase in the core autophagy pathway and thus represents an excellent drug target. Despite recent advances in the understanding of ULK1 activation by nutrient deprivation, how ULK1 promotes autophagy remains poorly understood. Here, we screened degenerate peptide libraries to deduce the optimal ULK1 substrate motif and discovered 15 phosphorylation sites in core autophagy proteins that were verified as in vivo ULK1 targets. We utilized these ULK1 substrates to perform a cell-based screen to identify and characterize a potent ULK1 small molecule inhibitor. The compound SBI-0206965 is a highly selective ULK1 kinase inhibitor in vitro and suppressed ULK1-mediated phosphorylation events in cells, regulating autophagy and cell survival. SBI-0206965 greatly synergized with mechanistic target of rapamycin (mTOR) inhibitors to kill tumor cells, providing a strong rationale for their combined use in the clinic.


Assuntos
Autofagia/fisiologia , Benzamidas/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Pirimidinas/farmacologia , Sequência de Aminoácidos , Animais , Autofagia/efeitos dos fármacos , Proteína Homóloga à Proteína-1 Relacionada à Autofagia , Benzamidas/química , Domínio Catalítico/genética , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Sequência Consenso , Técnicas de Inativação de Genes , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Camundongos , Dados de Sequência Molecular , Fosforilação , Inibidores de Proteínas Quinases/química , Proteínas Serina-Treonina Quinases/deficiência , Proteínas Serina-Treonina Quinases/genética , Pirimidinas/química , RNA Interferente Pequeno/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Especificidade por Substrato
3.
Molecules ; 28(15)2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37570873

RESUMO

Tectorigenin is a well-known natural flavonoid aglycone and an active component that exists in numerous plants. Growing evidence suggests that tectorigenin has multiple pharmacological effects, such as anticancer, antidiabetic, hepatoprotective, anti-inflammatory, antioxidative, antimicrobial, cardioprotective, and neuroprotective. These pharmacological properties provide the basis for the treatment of many kinds of illnesses, including several types of cancer, diabetes, hepatic fibrosis, osteoarthritis, Alzheimer's disease, etc. The purpose of this paper is to provide a comprehensive summary and review of the sources, extraction and synthesis, pharmacological effects, toxicity, pharmacokinetics, and delivery strategy aspects of tectorigenin. Tectorigenin may exert certain cytotoxicity, which is related to the administration time and concentration. Pharmacokinetic studies have demonstrated that the main metabolic pathways in rats for tectorigenin are glucuronidation, sulfation, demethylation and methoxylation, but that it exhibits poor bioavailability. From our perspective, further research on tectorigenin should cover: exploring the pharmacological targets and mechanisms of action; finding an appropriate concentration to balance pharmacological effects and toxicity; attempting diversified delivery strategies to improve the bioavailability; and structural modification to obtain tectorigenin derivatives with higher pharmacological activity.


Assuntos
Isoflavonas , Ratos , Animais , Isoflavonas/farmacologia , Isoflavonas/química , Disponibilidade Biológica , Flavonoides , Cirrose Hepática
4.
Mol Cell Biochem ; 477(1): 191-203, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34652536

RESUMO

Non-alcoholic fatty liver disease (NAFLD) was a world-wide health burden. H3K27 acetylation, long non-coding RNA (lncRNA), and miRNA were all implicated in NAFLD regulation, yet the detailed regulatory mechanism was not well understood. LncRNA NEAT1, miR-212-5p, and GRIA3 expression were detected both in high fatty acid-treated hepatocytes cells and NAFLD patients. Lipid droplets were stained and analyzed by oil red O staining. Expression of fatty acid synthase (FASN), acetyl-CoA carboxylase (ACC), and GRIA3 was detected by qRT-PCR and western blot. RNA level of lncRNA NEAT1 and miR-212-5p was analyzed by qRT-PCR. The binding sequences of lncRNA NEAT1/miR-212-5p and miR-212-5p/GRIA3 were predicted bioinformatically and validated through luciferase assay. ChIP was performed to analyze H3K27 acetylation on the promoter of lncRNA NEAT1. LncRNA NEAT1 and GRIA3 was upregulated, while miR-212-5p was downregulated in NAFLD patients. FFA promoted lncRNA NEAT1 and GRIA3 expression while suppressing miR-212-5p and promoted lipid accumulation as indicated by increased oil red O staining and FAS and ACC expression. ChIP indicated enrichment of H3K27 on NEAT1 promoter. Inhibition of H3K27 acetylation suppressed lncRNA NEAT1 level. Luciferase results indicated direct interaction of NEAT1/miR-212-5p (which was confirmed by RIP) and miR-212-5p/GRIA3. LncRNA NEAT1 knockdown upregulated miR-212-5p level and inhibited FFA-induced lipid accumulation while suppressing GRIA3 expression. Such function was antagonized by miR-212-5p inhibition and GRIA3 knockdown counteracted with miR-212-5p inhibition. H3K27 acetylation was enriched within the promoter of lncRNA NEAT1 and promoted lncRNA NEAT1 transcription. LncRNA NEAT1 could then interact with miR-212-5p and suppress its cellular concentration.


Assuntos
Histonas/genética , Metabolismo dos Lipídeos/fisiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , RNA Longo não Codificante/metabolismo , Receptores de AMPA/genética , Acetilação , Estudos de Casos e Controles , Ácidos Graxos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Histonas/metabolismo , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Lisina/metabolismo , MicroRNAs/genética , Hepatopatia Gordurosa não Alcoólica/genética , Receptores de AMPA/metabolismo
5.
Zhongguo Zhong Yao Za Zhi ; 47(23): 6514-6519, 2022 Dec.
Artigo em Zh | MEDLINE | ID: mdl-36604898

RESUMO

Compound Congrong Yizhi Capsules is widely used in clinic for the long-term treatment and synergistic treatment of vascular cognitive impairment. After years of clinical observation, it has an obvious curative effect on the treatement of vascular cognitive impairment and has been recommended by multiple guidelines, consensuses, and series. This consensus was formulated for the treatment of vascular dementia. On the basis of summarizing the application experience of clinicians, and combined with the existing evidence-based evidence, 11 recommendations/consensus recommendations were finally reached through the nominal group method. The indications, usage and dosage, course of treatment, medication time, concomitant medication, and precautions of Congrong Yizhi Capsules in the treatment of vascular dementia were proposed, and the safety of the clinical application was described. This consensus is applicable to the use of Compound Congrong Yizhi Capsules in the treatment of patients with vascular dementia, and can be used by clinicians from the departments of encephalopathy(neurology), geriatrics, and traditional Chinese medicine in general hospitals. This consensus has been approved by China Association of Chinese Medicine, with the number of GS/CACM 298-2022.


Assuntos
Demência Vascular , Medicamentos de Ervas Chinesas , Humanos , Demência Vascular/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Consenso , Cápsulas , Medicina Tradicional Chinesa
6.
Acta Pharmacol Sin ; 42(8): 1347-1353, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33116249

RESUMO

To discover effective drugs for COVID-19 treatment amongst already clinically approved drugs, we developed a high throughput screening assay for SARS-CoV-2 virus entry inhibitors using SARS2-S pseudotyped virus. An approved drug library of 1800 small molecular drugs was screened for SARS2 entry inhibitors and 15 active drugs were identified as specific SARS2-S pseudovirus entry inhibitors. Antiviral tests using native SARS-CoV-2 virus in Vero E6 cells confirmed that 7 of these drugs (clemastine, amiodarone, trimeprazine, bosutinib, toremifene, flupenthixol, and azelastine) significantly inhibited SARS2 replication, reducing supernatant viral RNA load with a promising level of activity. Three of the drugs were classified as histamine receptor antagonists with clemastine showing the strongest anti-SARS2 activity (EC50 = 0.95 ± 0.83 µM). Our work suggests that these 7 drugs could enter into further in vivo studies and clinical investigations for COVID-19 treatment.


Assuntos
Antivirais/uso terapêutico , Tratamento Farmacológico da COVID-19 , Reposicionamento de Medicamentos , SARS-CoV-2/efeitos dos fármacos , Internalização do Vírus/efeitos dos fármacos , Linhagem Celular , Aprovação de Drogas , Ensaios de Triagem em Larga Escala , Humanos , Testes de Sensibilidade Microbiana , SARS-CoV-2/fisiologia , Glicoproteína da Espícula de Coronavírus/efeitos dos fármacos
7.
Hum Genomics ; 13(1): 50, 2019 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-31519209

RESUMO

BACKGROUND: Pre-eclampsia (PE) is regarded as the leading cause of maternal and neonatal morbidity and mortality. Nevertheless, the potential mechanism for the regulation of trophoblast behaviors and the pathogenesis of PE remain largely elusive. Recently, accumulating evidence emphasized that aberrant expression of long non-coding RNAs (lncRNAs) functions as imperative regulators in human diseases, including PE. Thus, identifying PE-related specific lncRNAs to uncover the underlying molecular mechanism is of much significance. However, the functional roles and underlying mechanisms of lncRNAs in PE progression remain unclear. METHOD: Placenta tissues obtained from patients with PE and healthy pregnant women were performed to measure TUG1 expression by qRT-PCR analysis. Transient transfections were conducted to alter TUG1 expression. Cell Counting Kit-8 (CCK-8) and flow cytometry assays were carried out to assess cell proliferation and apoptosis, respectively. Transwell and tube formation assays were performed to measure the capacity of cell invasion and angiogenesis. Moreover, the luciferase reporter assay was subjected to verify the binding relationship between TUG1 and miR-29b. Western blot analysis was performed to detect the expression of key proteins in the PI3K/AKT and ERK pathway. RESULTS: Here, we identified a lncRNA, TUG1, which was notably decreased in placental samples of PE patients. Functional experiments of loss- or gain-of-function assays also verified that ectopic expression of TUG1 promoted cell proliferation, invasion, and angiogenesis, but negatively regulated cell apoptosis, whereas TUG1 inhibition presented the opposite effects. Furthermore, mechanistic researches revealed that TUG1 could act as a molecular sponge for miR-29b, thus regulating MCL1, VEGFA, and MMP2 to modulate PE development. CONCLUSIONS: Taken together, our findings demonstrated that TUG1 exerts as a critical role in PE progression, which might furnish a novel therapeutic marker for PE treatment.


Assuntos
Proliferação de Células/genética , MicroRNAs/genética , Pré-Eclâmpsia/genética , RNA Longo não Codificante/genética , Apoptose/genética , Linhagem Celular , Movimento Celular/genética , Feminino , Humanos , Metaloproteinase 2 da Matriz/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Placenta/metabolismo , Placenta/patologia , Pré-Eclâmpsia/patologia , Gravidez , Trofoblastos/metabolismo , Trofoblastos/patologia , Fator A de Crescimento do Endotélio Vascular/genética
8.
Biosci Biotechnol Biochem ; 84(8): 1645-1651, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32380907

RESUMO

Oxaliplatin (L-OHP) is one of the effective chemotherapeutic drugs for colorectal cancer (CRC). Further investigation into the molecular mechanism of chemoresistance could improve outcomes for patients with colorectal cancer. Recently, microRNAs have been reported as a key in drug resistance of tumors. In this study, we aimed to investigate the effects of miR-153-5p in L-OHP-resistant CRC cells, and its underlying mechanism. Downregulation of miR-153-5p was observed in CRC cells, while upregulation of miR-153-5p enhances the chemosensitivity of CRC/L-OHP cells. The autophagy of CRC/L-OHP cells was markedly increased after exposure to L-OHP but abolished by the upregulation of miR-153-5p. Dual-luciferase reporter assays validated that Bcl-2 was a direct target of miR-153-5p. In conclusion, our data suggested that miR-153-5p was a mediator of cisplatin resistance in colorectal cancer by affecting Bcl-2-mediated autophagy, indicating a new therapeutic target for CRC treatment.


Assuntos
Antineoplásicos/farmacologia , Autofagia/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , MicroRNAs/genética , Oxaliplatina/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Antagomirs/genética , Antagomirs/metabolismo , Autofagia/genética , Pareamento de Bases , Sequência de Bases , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Humanos , MicroRNAs/agonistas , MicroRNAs/antagonistas & inibidores , MicroRNAs/metabolismo , Oligorribonucleotídeos/genética , Oligorribonucleotídeos/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais
9.
Psychiatr Danub ; 32(2): 251-255, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32796794

RESUMO

Transmission of the 2019 novel coronavirus (COVID-19) has now rapidly spread around the world, which has alarming implications for individuals and communities, in particular for public mental health. Significant progress has been made in the prevention and control of the COVID-19 pandemic in China, but the psychological crisis caused by the epidemic is still not over and may continue to exist. The public mental health in the post-COVID-19 era should not be ignored. This article provides early warning for the public's mental health in the post-COVID-19 era by listing the characteristics and duration of the public mental health crisis following the SARS outbreak. In addition, based on the current situation, specific methods and measures are proposed in order to provide effective reference for the prevention and control of psychological crisis caused by the COVID-19 epidemic.


Assuntos
Infecções por Coronavirus , Saúde Mental/estatística & dados numéricos , Pandemias , Pneumonia Viral , Saúde Pública/estatística & dados numéricos , COVID-19 , Infecções por Coronavirus/epidemiologia , Humanos , Pneumonia Viral/epidemiologia
10.
Zhongguo Zhong Yao Za Zhi ; 45(8): 1924-1932, 2020 Apr.
Artigo em Zh | MEDLINE | ID: mdl-32489079

RESUMO

To analyze the efficacy and safety of Compound Congrong Yizhi Capsules in treatment of vascular cognitive impairment. Databases, such as CNKI, WanFang, VIP, SinoMed, PubMed, Cochrane Library, ClinicalTrials were electronically retrieved for relevant randomized controlled trials about the effect of Compound Congrong Yizhi Capsules in treatment of vascular cognitive impairment. Two researchers independently screened the literatures and extracted data according to the inclusion criteria, and used the risk of bias assessment tool in the Cochrane evaluation manual for quality assessment. The Cochrane systematic evaluation software RevMan 5.3 was used for data analysis. Totally 12 articles including 1 279 patients were included. The intervention measure was Compound Congrong Yizhi Capsules used alone or combined with Western medicine, and the control measure was the Western medicine alone or the blank control. According to the findings, for patients of vascular cognitive impairment no dementia, Compound Congrong Yizhi Capsules was better than the blank control in improving MoCA scale score and serum NO levels and reducing serum ET-1 levels. For vascular dementia patients, Compound Congrong Yizhi Capsules combined with Western medicine was better than Western medicine alone in improving MMSE and MoCA scale score. Five studies reported adverse events, but no significant adverse reaction was found. In conclusion, Compound Congrong Yizhi Capsules alone could alliviate early cognitive impairment in patients of vascular cognitive impairment no dementia; Compound Congrong Yizhi Capsules combined with Western medicine is superior to Western medicine alone in improving cognitive impairment. No obvious adverse reaction was found. Compound Congrong Yizhi Capsules can be recommended in clinical use. This conclusion needs to be further confirmed in high-quality clinical trials in the future.


Assuntos
Disfunção Cognitiva , Demência Vascular , Medicamentos de Ervas Chinesas , Alpinia , Cápsulas , Humanos , Extratos Vegetais
11.
Zhongguo Zhong Yao Za Zhi ; 45(10): 2296-2299, 2020 May.
Artigo em Zh | MEDLINE | ID: mdl-32495583

RESUMO

With the advancement of the aging process, cerebrovascular disease has become China's first cause of death. Injection of Breviscapine is a type of traditional Chinese medicine injections published in the Chinese Pharmacopoeia of 2015 Edition and the National Basic Medical Insurance, Industrial Injury Insurance and Maternity Insurance Drug Catalogue, and used to treat ischemic cerebrovascular disease in clinic. In order to further improve clinicians' understanding of the drug and guidance of its rational clinical use, we gave full consideration of clinical research evidences and expert experience, followed the procedures developed based on expert consensus of Chinese Academy of Traditional Chinese Medicine, and then offered recommendations for clinical problems summarized by clinical first-line investigations and evidence-based clinical problems according to internationally accepted evidence grading and recommendation standards, i.e. Grade. As for clinical problems without evidence, we reached through nominal group method, and formed consensus recommendations. Safety issues of Injection of Breviscapine, such as indication, syndrome, dosage, course of treatment, precautions, suggestions and contraindications, were defined to improve clinical efficacy, promote rational drug use and reduce drug risks. This consensus needs to be revised in the future based on emerging clinical issues and evidence-based updates in practical applications.


Assuntos
Medicamentos de Ervas Chinesas , China , Consenso , Feminino , Flavonoides , Humanos , Medicina Tradicional Chinesa , Gravidez
12.
Mod Pathol ; 32(11): 1566-1573, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31190000

RESUMO

The 2018 American Society of Clinical Oncology (ASCO) and College of American Pathologists (CAP) update modified the interpretation guidelines for human epidermal growth factor receptor 2 (HER2) testing by incorporating immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) results in a subset of cases. Importantly, the new guidelines eliminate "equivocal" results, as well as the use of alternative chromosome 17 probes as the primary strategy for resolving the indeterminate FISH results. Herein, we investigate the predicted impact of implementing the 2018 ASCO/CAP guidelines on HER2 assessment by FISH in breast cancers, using data from a single institution. We compared the HER2 status of 1542 consecutive cases of breast carcinoma, interpreted by 2013 and 2018 ASCO/CAP guidelines. In total, 10.7% (165/1542) of the cases had a different final interpretation by 2018 guidelines compared with 2013 guidelines, including 70 previously HER2-positive cases reclassified as negative, four previously negative cases reclassified as positive, and 91 previously equivocal cases reclassified as negative. Overall, the number of HER2-positive cancers was reduced by 66 cases (4.3% reduction in the HER2 positivity rate). The newly HER2-negative cases were mostly estrogen receptor positive (90%), progesterone receptor positive (80%), stage 1 (60.9%), and grade 1-2 (59.4%) cancers; 70% of them had been designated as HER2 positive only after the use of an alternative chromosome 17 FISH probe after an intially equivocal result from the standard CEP17 probe. Overall, implementing the revised 2018 HER2 guidelines is predicted to change the HER2 results of 10.7% of breast cancers, mainly by reclassifying previously equivocal to negative results.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/classificação , Hibridização in Situ Fluorescente/métodos , Guias de Prática Clínica como Assunto , Receptor ErbB-2/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Oncologia/normas , Pessoa de Meia-Idade , Adulto Jovem
13.
Bioorg Med Chem Lett ; 29(19): 126577, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31421967

RESUMO

Bromodomain-containing protein 4 (BRD4), a member of the bromodomain and extra-terminal (BET) family, has been recognized as an attractive candidate target for the treatment targeting gene transcription in several types of cancers. In this study, two types of novel compounds were designed, synthesized and evaluated as BRD4 inhibitors. Therein, pyridone derivatives were more effective against BRD4 protein and human leukemia cell lines MV4-11. Among them, compounds 11d, 11e and 11f were the most potential ones with IC50 values of 0.55 µM, 0.86 µM and 0.80 µM against BRD4, and exhibited remarkable antiproliferative activities against MV4-11 cells with IC50 values of 0.19 µM, 0.32 µM and 0.12 µM, respectively. Moreover, in western blot assay, compound 11e induced down-regulation of C-Myc, which is a significant downstream gene of BRD4. Cell cycle analysis assay also showed that compound 11e could block MV4-11 cells at G0/G1 phase. Taken together, our results suggested that compound 11e and its derivatives were a class of novel structural potential BRD4 inhibitors and could serve as lead compounds for further exploration.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Proteínas de Ciclo Celular/antagonistas & inibidores , Desenho de Fármacos , Isoxazóis/química , Leucemia/tratamento farmacológico , Piridonas/química , Fatores de Transcrição/antagonistas & inibidores , Ciclo Celular , Humanos , Proteínas Proto-Oncogênicas c-myc/antagonistas & inibidores , Células Tumorais Cultivadas
14.
Artigo em Inglês | MEDLINE | ID: mdl-29686156

RESUMO

Tuberculosis is a major global health problem, and the emergence of multidrug-resistant and extensively drug-resistant strains has increased the difficulty of treating this disease. Among the novel antituberculosis drugs in the pipeline, decaprenylphosphoryl-beta-d-ribose-2-epimerase (DprE1) inhibitors such as BTZ043 and pBTZ169 exhibited extraordinary antituberculosis potency. Here, the metabolites of the new DprE1 inhibitor SKLB-TB1001 in vivo and its inhibition of cytochrome P450 isoforms and plasma protein binding (PPB) in vitro were studied. The results showed that rapid transformation and high PPB resulted in inadequate exposure in vivo and thus led to the moderate potency of SKLB-TB1001 in vivo This study provided explanations for the discrepant potency of this scaffold in vivo and in vitro Meanwhile, it also provides a rationale for lead optimization of this very promising scaffold of antituberculosis agents to prevent them from being metabolized, thus improving their exposure in vivo.


Assuntos
Antituberculosos/farmacocinética , Proteínas de Bactérias/metabolismo , Tuberculose/tratamento farmacológico , Animais , Antituberculosos/química , Proteínas de Bactérias/genética , Camundongos , Estrutura Molecular , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade , Espectrometria de Massas em Tandem , Tuberculose/metabolismo
16.
Biophys J ; 112(10): 2173-2183, 2017 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-28538154

RESUMO

The interactions between Ca2+ ions and sphingomyelin play crucial roles in a wide range of cellular activities. However, little is known about the molecular details of the interactions at interfaces. In this work, we investigated the interactions between Ca2+ ions and egg sphingomyelin (ESM) Langmuir monolayers at the air/water interface by subwavenumber high-resolution broadband sum frequency generation vibrational spectroscopy (HR-BB-SFG-VS). We show that Ca2+ ions can induce ordering of the acyl chains in the ESM monolayer. An analysis of the one alkyl-chain-deuterated ESM revealed that the Ca2+ ions do not affect the N-linked saturated fatty acid chain, although they make the sphingosine backbone become ordered. Further analysis of the SFG-VS spectra shows that the interactions between ESM and Ca2+ ions make the orientation of the methyl group at the end of sphingosine backbone change from pointing downward to pointing upward. Moreover, a large blue shift of the phosphate group at the CaCl2 solution interface indicates, to our knowledge, new cation binding modes. Such binding causes the phosphate moiety to dehydrate, resulting in the conformation change of the phosphate moiety. Based on these results, we propose the molecular mechanism that Ca2+ ions can bind to the phosphate group and subsequently destroy the intramolecular hydrogen bond between the 3-hydroxyl group and the phosphate oxygen, which results in an ordering change of the sphingosine backbone. These findings illustrate the potential application of HR-BB-SFG-VS to investigate lipid-cation interactions and the calcium channel modulated by lipid domain formation through slight structural changes in the membrane lipid. It will also shed light on the interactions of complex molecules at surfaces and interfaces.


Assuntos
Cálcio/metabolismo , Esfingomielinas/metabolismo , Ar , Animais , Cloreto de Cálcio/química , Cátions Bivalentes/metabolismo , Galinhas , Proteínas do Ovo/metabolismo , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Pressão , Soluções , Análise Espectral , Propriedades de Superfície , Vibração , Água/química
17.
Zhongguo Zhong Yao Za Zhi ; 42(16): 3112-3120, 2017 Aug.
Artigo em Zh | MEDLINE | ID: mdl-29171229

RESUMO

To analyze the dynamic changes in components in exocarp of Juglans mandshurica at different browning periods. Twenty-six batches of exocarp of J. mandshurica samples from thirteen browning periods were assessed by UPLC-Q-TOF-MS/MS. The formula of different compounds were determined by accurate mass and isotopic abundance ratio from target screening function of Peakview 2.0/masterview1.0 software. Then their structures were determined by analysis of MS/MS fragment or comparison with standard substances and references. The contents of chemical components were changed significantly in different browning periods and twenty five compounds were identified or inferred. Of the 13 naphthoquinone compounds, the contents of 6 compounds with similar parent nucleus as juglone and 3 naphthoquinone glycosides compounds were decreased significantly, and 4 naphthoquinone derivatives such as regiolone were produced; the contents of four flavones and two phenolic acids compounds were decreased significantly; and the contents of 6 diarylheptanoids compounds were increased significantly. UPLC-Q-TOF/MS method can be used to identify and analyze the chemical constituents from exocarp of J. mandshurica rapidly and accurately, and analyze the rules of dynamic changes, to reveal the browning of Chinese medicinal materials and its effects on compositions of fruits and vegetables.


Assuntos
Frutas/química , Juglans/química , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/química , Flavonas/análise , Glicosídeos/análise , Hidroxibenzoatos/análise , Naftoquinonas/análise , Oxirredução , Espectrometria de Massas em Tandem
18.
J Chem Phys ; 145(24): 244707, 2016 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-28049317

RESUMO

The interfacial behavior of the benchmark zwitterionic phospholipid molecule dipalmitoylphosphatidylcholine (DPPC) has been extensively investigated by surface-selective vibrational sum frequency generation spectroscopy (VSFG). However, there is still a lack of agreement between various orientational measurements of phospholipid monolayers at the air/water interface, mainly because of the difficulty in assigning congested VSFG features. In this study, polarization-dependent VSFG measurements reveal a frequency shift between the in-plane and out-of-plane antisymmetric stretching modes of the terminal methyl groups in the DPPC alkyl tails, favoring the model of Cs local symmetry rather than the previously assumed C3v symmetry. Further VSFG experiments of isotopically labeled DPPC successfully capture the vibrational signatures of the glycerol backbone. With the newly derived VSFG polarization selection rules for Cs symmetry and the refreshed spectral assignments, the average tilt angles of the alkyl tail groups, choline headgroup, and glycerol backbone of DPPC molecules can all be determined, showing the powerful capability of VSFG spectroscopy in revealing the structural details at interfaces. The VSFG polarization dependence rules and the orientational analysis procedures developed for Cs symmetry in this work are applicable to other bulky molecules in which the methyl group cannot freely rotate, and they therefore have general applications in future VSFG studies.


Assuntos
1,2-Dipalmitoilfosfatidilcolina/química , Ar , Vibração , Água/química , Colina/química , Glicerol/química , Modelos Moleculares , Conformação Molecular , Análise Espectral , Propriedades de Superfície
19.
Opt Express ; 23(8): 9658-63, 2015 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-25969002

RESUMO

We experimentally demonstrate a broadband one-way transmission by merging the operating bands of two types of one-way edge modes that are associated with Bragg scattering and magnetic surface plasmon (MSP) resonance, respectively. By tuning the configuration of gyromagnetic photonic crystals and applied bias magnetic field, the fused bandwidth of unidirectional propagation is up to 2 GHz in microwave frequency range, much larger than either of the individual one-way bandwidth associated with Bragg scattering or MSP resonance. Our scheme for broadband one-way transmission paves the way for the practical applications of one-way transmission.

20.
Phys Rev Lett ; 115(8): 083902, 2015 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-26340190

RESUMO

Nonlinear frequency conversion offers an effective way to expand the laser wavelength range based on birefringence phase matching (BPM) or quasi-phase-matching (QPM) techniques in nonlinear crystals. So far, efficient high-harmonic generation is enabled only via multiple cascaded crystals because of the extreme difficulty to simultaneously satisfy BPM or QPM for multiple nonlinear up-conversion processes within a single crystal. Here we report the design and fabrication of a chirped periodic poled lithium niobate (CPPLN) nonlinear crystal that offers controllable multiple QPM bands to support 2nd-8th harmonic generation (HG) simultaneously. Upon illumination of a mid-IR femtosecond pulse laser, we observe the generation of an ultrabroadband visible white light beam corresponding to 5th-8th HG with a record high conversion efficiency of 18%, which is high compared to conventional supercontinuum generation, especially in the HG parts. Our CPPLN scheme opens up a new avenue to explore and engineer novel nonlinear optical interactions in solid state materials for application in ultrafast lasers and broadband laser sources.

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