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1.
Immunity ; 51(3): 522-534.e7, 2019 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-31471107

RESUMO

Although recent progress provides mechanistic insights into the pathogenesis of pulmonary fibrosis (PF), rare anti-PF therapeutics show definitive promise for treating this disease. Repeated lung epithelial injury results in injury-repairing response and inflammation, which drive the development of PF. Here, we report that chronic lung injury inactivated the ubiquitin-editing enzyme A20, causing progressive accumulation of the transcription factor C/EBPß in alveolar macrophages (AMs) from PF patients and mice, which upregulated a number of immunosuppressive and profibrotic factors promoting PF development. In response to chronic lung injury, elevated glycogen synthase kinase-3ß (GSK-3ß) interacted with and phosphorylated A20 to suppress C/EBPß degradation. Ectopic expression of A20 or pharmacological restoration of A20 activity by disturbing the A20-GSK-3ß interaction accelerated C/EBPß degradation and showed potent therapeutic efficacy against experimental PF. Our study indicates that a regulatory mechanism of the GSK-3ß-A20-C/EBPß axis in AMs may be a potential target for treating PF and fibroproliferative lung diseases.


Assuntos
Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Macrófagos/metabolismo , Fibrose Pulmonar/metabolismo , Fatores de Transcrição/metabolismo , Ubiquitina/metabolismo , Animais , Linhagem Celular , Glicogênio Sintase Quinase 3 beta/metabolismo , Células HEK293 , Humanos , Inflamação/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação/fisiologia , Transdução de Sinais/fisiologia , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação/fisiologia , Regulação para Cima/fisiologia
2.
JAMA ; 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38820549

RESUMO

Importance: For patients with non-small cell lung cancer whose disease progressed while receiving EGFR tyrosine kinase inhibitor (EGFR-TKI) therapy, particularly third-generation TKIs, optimal treatment options remain limited. Objective: To compare the efficacy of ivonescimab plus chemotherapy with chemotherapy alone for patients with relapsed advanced or metastatic non-small cell lung cancer with the epidermal growth factor receptor (EGFR) variant. Design, Setting, and Participants: Double-blind, placebo-controlled, randomized, phase 3 trial at 55 sites in China enrolled participants from January 2022 to November 2022; a total of 322 eligible patients were enrolled. Interventions: Participants received ivonescimab (n = 161) or placebo (n = 161) plus pemetrexed and carboplatin once every 3 weeks for 4 cycles, followed by maintenance therapy of ivonescimab plus pemetrexed or placebo plus pemetrexed. Main Outcomes and Measures: The primary end point was progression-free survival in the intention-to-treat population assessed by an independent radiographic review committee (IRRC) per Response Evaluation Criteria in Solid Tumors version 1.1. The results of the first planned interim analysis are reported. Results: Among 322 enrolled patients in the ivonescimab and placebo groups, the median age was 59.6 vs 59.4 years and 52.2% vs 50.9% of patients were female. As of March 10, 2023, median follow-up time was 7.89 months. Median progression-free survival was 7.1 (95% CI, 5.9-8.7) months in the ivonescimab group vs 4.8 (95% CI, 4.2-5.6) months for placebo (difference, 2.3 months; hazard ratio [HR], 0.46 [95% CI, 0.34-0.62]; P < .001). The prespecified subgroup analysis showed progression-free survival benefit favoring patients receiving ivonescimab over placebo across almost all subgroups, including patients whose disease progressed while receiving third-generation EGFR-TKI therapy (HR, 0.48 [95% CI 0.35-0.66]) and those with brain metastases (HR, 0.40 [95% CI, 0.22-0.73]). The objective response rate was 50.6% (95% CI, 42.6%-58.6%) with ivonescimab and 35.4% (95% CI, 28.0%-43.3%) with placebo (difference, 15.6% [95% CI, 5.3%-26.0%]; P = .006). The median overall survival data were not mature; at data cutoff, 69 patients (21.4%) had died. Grade 3 or higher treatment-emergent adverse events occurred in 99 patients (61.5%) in the ivonescimab group vs 79 patients (49.1%) in the placebo group, the most common of which were chemotherapy-related. Grade 3 or higher immune-related adverse events occurred in 10 patients (6.2%) in the ivonescimab group vs 4 (2.5%) in the placebo group. Grade 3 or higher vascular endothelial growth factor-related adverse events occurred in 5 patients (3.1%) in the ivonescimab group vs 4 (2.5%) in the placebo group. Conclusions: Ivonescimab plus chemotherapy significantly improved progression-free survival with tolerable safety profile in TKI-treated non-small cell lung cancer. Trial Registration: ClinicalTrials.gov Identifier: NCT05184712.

3.
Chin Med Sci J ; 39(2): 149-154, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38773789

RESUMO

Vertebral artery dissection is a rare pathology that can cause ischemic stroke in young people. Cervical massage, especially improper pulling manipulation, is a cause of vertebral artery dissection. We present a case of 32-year-old woman who developed acute multiple posterior circulation ischemic cerebral infarctions as a result of left vertebral artery V4 segment dissection after receiving neck massage. She underwent emergency vertebral artery stent implantation at the site of the dissection. Symptoms were relieved the day after treatment. The patient recovered without adverse complications or endovascular restenosis in the following year.


Assuntos
Infarto Cerebral , Massagem , Stents , Dissecação da Artéria Vertebral , Humanos , Feminino , Dissecação da Artéria Vertebral/diagnóstico por imagem , Dissecação da Artéria Vertebral/etiologia , Dissecação da Artéria Vertebral/cirurgia , Adulto , Stents/efeitos adversos , Massagem/efeitos adversos , Infarto Cerebral/etiologia , Infarto Cerebral/diagnóstico por imagem , Artéria Vertebral/diagnóstico por imagem , Artéria Vertebral/cirurgia
4.
Zhongguo Zhong Yao Za Zhi ; 49(1): 175-184, 2024 Jan.
Artigo em Zh | MEDLINE | ID: mdl-38403350

RESUMO

The occurrence and development of tumors are associated with the cell energy metabolism. Inhibiting energy metabolism of lung cancer cells is an important strategy to overcome drug resistance. Based on the cellular energy metabolism pathway, this study observed the effect of combination of shikonin(SKN) and gefitinib(GFB) on the drug resistance in non-small cell lung cancer and explored the underlying mechanism. The human non-small cell lung cancer line HCC827/GR resistant to gefitinib was used as the cell model in vitro. The CCK-8 assay and flow cytometry were employed to investigate the cell viability and apoptosis, respectively. The high performance liquid chromatography was employed to measure the intracellular accumulation of GFB. A Seahorse XFe96 Analyzer was used to detect the changes of cellular energy metabolism. Western blot was employed to determine the expression of the proteins involved in the drug resistance. The tumor-bearing nude mouse model was used to verify the efficacy of SKN+GFB in overcoming drug resistance in vivo. The results showed that SKN+GFB significantly reduced the IC_(50) of GFB on HCC827/GR cells, with the combination index of 0.628, indicating that the combination of the two drugs had a synergistic effect and promoted cell apoptosis. SKN increased the intracellular accumulation of GFB. SKN+GFB lowered the oxygen consumption rate(OCR) and glycolytic proton efflux rate(GlycoPER) in cell energy metabolism, and down-regulated the overexpression of PKM2, p-EGFR, P-gp, and HIF-1α in drug resistance. The results of reversing drug resistance test in vivo showed that GFB or SKN alone had no significant antitumor effect, while the combination at different doses induced the apoptosis of the tumor tissue and inhibited the expression of PKM2 and P-gp, demonstrating a significant antitumor effect. Moreover, the tumor inhibition rate in the high-dose combination group reached 64.01%. In summary, SKN+GFB may interfere with the energy metabolism to limit the function of HCC827/GR cells, thus reversing the GFB resistance in non-small cell lung cancer.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Naftoquinonas , Animais , Camundongos , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Gefitinibe/farmacologia , Gefitinibe/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Quinazolinas/farmacologia , Resistencia a Medicamentos Antineoplásicos , Proliferação de Células , Linhagem Celular Tumoral , Apoptose
5.
Int J Neuropsychopharmacol ; 26(9): 585-598, 2023 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-37490542

RESUMO

BACKGROUND: Alzheimer disease (AD) and depression often cooccur, and inhibition of phosphodiesterase-4 (PDE4) has been shown to ameliorate neurodegenerative illness. Therefore, we explored whether PDE4 inhibitor rolipram might also improve the symptoms of comorbid AD and depression. METHODS: APP/PS1/tau mice (10 months old) were treated with or without daily i.p. injections of rolipram for 10 days. The animal groups were compared in behavioral tests related to learning, memory, anxiety, and depression. Neurochemical measures were conducted to explore the underlying mechanism of rolipram. RESULTS: Rolipram attenuated cognitive decline as well as anxiety- and depression-like behaviors. These benefits were attributed at least partly to the downregulation of amyloid-ß, Amyloid precursor protein (APP), and Presenilin 1 (PS1); lower tau phosphorylation; greater neuronal survival; and normalized glial cell function following rolipram treatment. In addition, rolipram upregulated B-cell lymphoma-2 (Bcl-2) and downregulated Bcl-2-associated X protein (Bax) to reduce apoptosis; it also downregulated interleukin-1ß, interleukin-6, and tumor necrosis factor-α to restrain neuroinflammation. Furthermore, rolipram increased cAMP, PKA, 26S proteasome, EPAC2, and phosphorylation of ERK1/2 while decreasing EPAC1. CONCLUSIONS: Rolipram may mitigate cognitive deficits and depression-like behavior by reducing amyloid-ß pathology, tau phosphorylation, neuroinflammation, and apoptosis. These effects may be mediated by stimulating cAMP/PKA/26S and cAMP/exchange protein directly activated by cAMP (EPAC)/ERK signaling pathways. This study suggests that PDE4 inhibitor rolipram can be an effective target for treatment of comorbid AD and depression.


Assuntos
Doença de Alzheimer , Inibidores da Fosfodiesterase 4 , Camundongos , Animais , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/farmacologia , Rolipram/farmacologia , Camundongos Transgênicos , Inibidores da Fosfodiesterase 4/farmacologia , Doenças Neuroinflamatórias , Presenilina-1/metabolismo , Presenilina-1/farmacologia , Depressão/tratamento farmacológico , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Transtornos da Memória/tratamento farmacológico , Apoptose , Modelos Animais de Doenças
6.
FASEB J ; 36(6): e22376, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35616355

RESUMO

Pulsed electromagnetic fields (PEMFs) have long been recognized being safe and effective in treating bone fracture nonunion and osteoporosis. However, the mechanism of osteogenic action of PEMFs is still unclear. While primary cilia are reported to be a sensory organelle for PEMFs, and nitric oxide (NO) plays an indispensable role in osteogenic effect of PEMFs, the relationship between NO and primary cilia is unknown. In this study, effects of treatment with 50 Hz 0.6 mT PEMFs on osteogenic differentiation and mineralization, NO secretion, and ciliary location of specific proteins were examined in rat calvarial osteoblasts (ROBs) with normal or abrogated primary cilia. It was found that PEMFs stimulated the osteogenic differentiation by activating the NOS/NO/sGC/cGMP/PKG signaling pathway, which need the existence of primary cilia. All components of the signaling pathway including iNOS, eNOS, sGC, PKG-1, and PKG-2 were localized to primary cilia, and eNOS was phosphorylated inside the primary cilia. Besides, primary cilia were elongated significantly by PEMF treatment and changed dynamically with the activation NO/cGMP pathway. When the pathway was blocked by L-NAME, PEMFs could no longer elongate the primary cilia and stimulate the osteoblastic differentiation. Thus, this study for the first time observed activation of the NO/cGMP signaling pathway in ciliary compartment of osteoblasts, and PEMFs could not stimulate the osteoblastic differentiation if the NO signaling pathway was blocked or the ciliogenesis was inhibited. Our findings indicate the interdependent relationship between NO and primary cilia in the PEMF-promoted osteogenesis.


Assuntos
Campos Eletromagnéticos , Osteogênese , Animais , Diferenciação Celular , Cílios/metabolismo , GMP Cíclico/metabolismo , Óxido Nítrico/metabolismo , Osteoblastos/metabolismo , Ratos , Transdução de Sinais
7.
Acta Biochim Biophys Sin (Shanghai) ; 55(7): 1084-1098, 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37294105

RESUMO

Ubiquitination, a post-translational modification that attaches one or more ubiquitin (Ub) molecules to another protein, plays a crucial role in the phase-separation processes. Ubiquitination can modulate the formation of membrane-less organelles in two ways. First, a scaffold protein drives phase separation, and Ub is recruited to the condensates. Second, Ub actively phase-separates through the interactions with other proteins. Thus, the role of ubiquitination and the resulting polyUb chains ranges from bystanders to active participants in phase separation. Moreover, long polyUb chains may be the primary driving force for phase separation. We further discuss that the different roles can be determined by the lengths and linkages of polyUb chains which provide preorganized and multivalent binding platforms for other client proteins. Together, ubiquitination adds a new layer of regulation for the flow of material and information upon cellular compartmentalization of proteins.


Assuntos
Poliubiquitina , Ubiquitina , Humanos , Poliubiquitina/química , Poliubiquitina/metabolismo , Ubiquitinação , Ubiquitina/metabolismo
8.
BMC Med ; 20(1): 398, 2022 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-36372873

RESUMO

BACKGROUND: Due to the blood-brain barrier, plasma is not an ideal source to evaluate the genetic characteristics of central nervous system tumors. Thus, cerebrospinal fluid (CSF) is becoming an alternative biopsy type to evaluate the genetic landscape of intracranial tumors. We aimed to explore the genetic profiles of CSF-derived circulating tumor DNA (ctDNA) to predict intracranial tumor responses and monitor mutational evolution during the treatment of non-small cell lung cancer (NSCLC) patients with brain metastases. METHODS: We conducted a prospective study of 92 newly diagnosed NSCLC patients with brain metastases. Paired CSF and plasma samples were collected at baseline, 8 weeks after treatment initiation, and disease progression. All samples underwent next-generation sequencing of 425 cancer-related genes. RESULTS: At baseline, the positive detection rates of ctDNA in CSF, plasma, and extracranial tumors were 63.7% (58/91), 91.1% (82/90), and 100% (58/58), respectively. A high level of genetic heterogeneity was observed between paired CSF and plasma, while concordance in driver mutations was also observed. A higher number of unique copy number variations was detected in CSF-ctDNA than in plasma. ctDNA positivity of CSF samples at baseline was associated with poor outcomes (HR=2.565, P=0.003). Moreover, patients with ≥ 50% reductions in the concentrations of CSF ctDNA after 8 weeks of treatment had significantly longer intracranial progression-free survivals (PFS) than patients with < 50% reductions in CSF ctDNA concentrations (13.27 months vs 6.13 months, HR=0.308, P=0.017). A ≥ 50% reduction in CSF ctDNA concentrations had better concordance with radiographic intracranial tumor responses than plasma. A ≥ 50% reduction in plasma ctDNA concentrations was also associated with longer extracranial PFS (11.57 months vs 6.20 months, HR=0.406, P=0.033). Based on clonal evolution analyses, the accumulation of subclonal mutations in CSF ctDNA was observed after 8 weeks of treatment. The clonal mutations that remained in more than 80% in CSF after 8 weeks also predicted shorter intracranial PFS (HR=3.785, P=0.039). CONCLUSIONS: CSF ctDNA exhibited unique genetic profiles of brain metastases, and dynamic changes in CSF ctDNA could better predict intracranial tumor responses and track clonal evolution during treatment in NSCLC patients with brain metastases. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03257735.


Assuntos
Neoplasias Encefálicas , Carcinoma Pulmonar de Células não Pequenas , DNA Tumoral Circulante , Neoplasias Pulmonares , Humanos , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/análise , Encéfalo/patologia , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/genética , DNA Tumoral Circulante/genética , Variações do Número de Cópias de DNA , Perfil Genético , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Mutação , Estudos Prospectivos
9.
Future Oncol ; 18(9): 1159-1169, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35109665

RESUMO

Background: The role of adjuvant EGFR tyrosine kinase inhibitors (TKIs) in resected EGFR-mutated non-small-cell lung cancer (NSCLC) remains unclear. Materials & methods: We evaluated pooled hazard ratio and 95% CI for disease-free survival, overall survival and prespecified subgroups. Results: Seven prospective studies with 1288 patients were included in the meta-analysis. Adjuvant EGFR TKIs significantly improved disease-free survival in EGFR-mutated resected NSCLC (HR: 0.41; 95% CI: 0.24-0.70) and in all subgroups. However, the overall survival benefit was not significant (HR: 0.65; 95% CI: 0.36-1.17). The benefit of adjuvant TKIs may be associated with TKI regimens, treatment duration, pathological stage and EGFR mutation type. Conclusion: Adjuvant EGFR TKIs significantly improved disease-free survival and nonsignificantly improved overall survival in resected EGFR-mutated NSCLC.


For lung cancer patients who undergo radical surgery and whose tumors have EGFR mutation (a specific gene alteration in the tumor tissue), the optimal treatment following surgery is unclear. We summarized the available studies to compare the efficacy of anti-EGFR targeted therapies (EGFR inhibitors) with chemotherapy in patients after surgery. We found patients who received EGFR inhibitors after surgery had longer survival without disease recurrence, and a tendency toward longer overall survival than patients who received chemotherapy or no further therapy. The different treatment regimes, treatment duration, tumor stage and EGFR mutation type may impact the efficacy of EGFR inhibitors in these patients after undergoing surgery.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Quimioterapia Adjuvante , Terapia Combinada , Intervalo Livre de Doença , Receptores ErbB/antagonistas & inibidores , Humanos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/cirurgia , Inibidores de Proteínas Quinases/administração & dosagem
10.
Chemphyschem ; 22(14): 1505-1517, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-33928740

RESUMO

Linear polyubiquitin chains regulate diverse signaling proteins, in which the chains adopt various conformations to recognize different target proteins. Thus, the structural plasticity of the chains plays an important role in controlling the binding events. Herein, paramagnetic NMR spectroscopy is employed to explore the conformational space sampled by linear diubiquitin, a minimal unit of linear polyubiquitin, in its free state. Rigorous analysis of the data suggests that, regarding the relative positions of the ubiquitin units, particular regions of conformational space are preferentially sampled by the molecule. By combining these results with further data collected for charge-reversal derivatives of linear diubiquitin, structural insights into the factors underlying the binding events of linear diubiquitin are obtained.


Assuntos
Ubiquitinas/química , Espectroscopia de Ressonância de Spin Eletrônica , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Domínios Proteicos
11.
Chem Rec ; 21(6): 1442-1454, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33570239

RESUMO

The development of new and efficient methodology for the construction of optically active molecules is of great interest in both synthetic organic and medicinal chemistry fields. To this end, the personal account summarizes our studies on the development of electron-deficient alkenes, allenes, and alkynes containing single activator as new dipolarophiles for Pd-catalyzed asymmetric cycloaddition reactions. These new dipolarophiles can participate in Pd-catalyzed asymmetric [3+2] and [4+2] cycloadditions through Pd-π-allyl 1,3- and 1,4-zwitterions in-situ generated by the reaction of Pd(0) catalyst with vinyl aziridines, vinyl epoxides, vinyl cyclopropanes, 4-vinyl-1,3-dioxan-2-ones, and vinyl benzoxazinanones. These [3+2] and [4+2] cycloadditions provide efficient approaches to a wide range of enantiomerically enriched five- and six-membered ring compounds containing contiguous chiral centers with high to excellent chemo-, diastereo-, and enantioselectivities. The utilities of these protocols are demonstrated by transformation of the cycloadducts into other useful chiral building blocks. DFT calculations reveal the dissimilar reactivity of different electron deficient alkenes and rationalize the mechanism and stereo-control of the reaction. A Pd-catalyzed inverse [3+2] cycloaddition is disclosed.

12.
Environ Sci Technol ; 55(13): 8730-8741, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34169723

RESUMO

Perfluorooctanesulfonate (PFOS) as an accumulative emerging persistent organic pollutant in crops poses severe threats to human health. Lettuce varieties that accumulate a lower amount of PFOS (low-accumulating crop variety, LACV) have been identified, but the regarding mechanisms remain unsolved. Here, rhizospheric activation, uptake, translocation, and compartmentalization of PFOS in LACV were investigated in comparison with those of high-accumulating crop variety (HACV) in terms of rhizospheric forms, transporters, and subcellular distributions of PFOS. The enhanced PFOS desorption from the rhizosphere soils by dissolved organic matter from root exudates was observed with weaker effect in LACV than in HACV. PFOS root uptake was controlled by a transporter-mediated passive process in which low activities of aquaporins and rapid-type anion channels were corrected with low expression levels of PIPs (PIP1-1 and PIP2-2) and ALMTs (ALMT10 and ALMT13) genes in LACV roots. Higher PFOS proportions in root cell walls and trophoplasts caused lower root-to-shoot transport in LACV. The ability to cope with PFOS toxicity to shoot cells was poorer in LACV relative to HACV since PFOS proportions were higher in chloroplasts but lower in vacuoles. Our findings provide novel insights into PFOS accumulation in lettuce and further understanding of multiprocess mechanisms of LACV.


Assuntos
Ácidos Alcanossulfônicos , Fluorocarbonos , Poluentes do Solo , Fluorocarbonos/análise , Humanos , Lactuca , Solo , Poluentes do Solo/análise
13.
J Nat Prod ; 84(1): 11-19, 2021 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-33356261

RESUMO

Under the guidance of MS/MS-based molecular networking, four new cycloheptapeptides, namely, asperheptatides A-D (1-4), were isolated together with three known analogues, asperversiamide A-C (5-7), from the coral-derived fungus Aspergillus versicolor. The planar structures of the two major compounds, asperheptatides A and B (1 and 2), were determined by comprehensive spectroscopic data analysis. The absolute configurations of the amino acid residues were determined by advanced Marfey's method. The two structurally related trace metabolites, asperheptatides C and D (3 and 4), were characterized by ESI-MS/MS fragmentation methods. A series of new derivatives (8-26) of asperversiamide A (5) were semisynthesized. The antitubercular activities of 1, 2, and 5-26 against Mycobacterium tuberculosis H37Ra were also evaluated. Compounds 9, 13, 23, and 24 showed moderate activities with MIC values of 12.5 µM, representing a potential new class of antitubercular agents.


Assuntos
Agaricales/química , Antozoários/microbiologia , Antituberculosos/química , Aspergillus/química , Cinamatos/química , Mycobacterium tuberculosis/química , Peptídeos Cíclicos/química , Animais , Cromatografia Líquida , Cinamatos/farmacologia , Estrutura Molecular , Peptídeos Cíclicos/metabolismo , Análise Espectral , Espectrometria de Massas em Tandem
14.
J Am Chem Soc ; 142(45): 19354-19359, 2020 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-33140959

RESUMO

Spirocyclic hexadienones with multiple stereogenic centers are frequently found in natural products but remain challenging targets to synthesize. Herein, we report the enantioselective desymmetrization of bisphenol derivatives via Ir-catalyzed allylic dearomatization reactions, affording spirocyclic hexadienone derivatives with up to three contiguous stereogenic centers in good yields (up to 90%) and excellent enantioselectivity (up to 99% ee). The high efficiency of this reaction is exemplified by the short reaction time (30 min), low catalyst loading (down to 0.2 mol %), and ability to perform the reaction on a gram-scale. The total syntheses of (+)-tatanan B and (+)-tatanan C were also realized using this Ir-catalyzed allylic dearomatization reaction as a key step.

15.
J Sep Sci ; 43(4): 788-798, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31755653

RESUMO

In this study, a modified quick, easy, cheap, effective, rugged, and safe method combined with ultra-high performance liquid chromatography and tandem mass spectrometry was developed for the multiclass determination of 28 plant growth regulators in various fruits. Different extraction solvents and adsorbents, including primary secondary amine, octadecylsilyl, graphitized carbon black, and zirconia-based sorbent, were investigated. Internal calibration and isotope internal standards, chlormequat chloride-d4 , mepiquat chloride-d6 , indole-3-acetic acid-d2 , and forchlorfenuron-d5 were used to improve accuracy. For method validation, good linearity, low limits of detection and quantification were obtained. At three spiked concentrations (10, 50, and 100 µg/kg), satisfactory recoveries with relative standard deviations of 2.4-17.5% were obtained for strawberries (75.2-119.8%), grapes (70.5-114.0%), tangerines (71.7-115.4%), apples (72.7-115.4%), and kiwi fruits (71.7-119.2%). Samples analysis revealed that 15.6% of the samples (n = 96) were contaminated with one or two kinds of plant growth regulators, including chlormequat chloride, forchlorfenuron, paclobutrazol, 2,4-dichlorophenoxyacetic acid, 2-diethylaminoethyl hexanoate, and mepiquat chloride. Similar results were obtained by ultra-high performance liquid chromatography with quadrupole time-of-flight mass spectrometry, indicating the robustness, effectiveness, and suitability of the developed method for routine monitoring of plant growth regulator residues in fruits.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Resíduos de Drogas/química , Frutas/química , Reguladores de Crescimento de Plantas/química , Espectrometria de Massas em Tandem/métodos , Actinidia/química , Resíduos de Drogas/isolamento & purificação , Contaminação de Alimentos/análise , Fragaria/química , Malus/química , Reguladores de Crescimento de Plantas/isolamento & purificação , Extração em Fase Sólida , Vitis/química
16.
Metab Brain Dis ; 35(1): 83-93, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31440984

RESUMO

Post-stroke fatigue (PSF) is a common symptom after stroke and interferes with the rehabilitation. There are limited pharmacological therapies for managing PSF. Astragalus membranaceus (Huangqi) is a frequently used Chinese herbal medicine (CHM) in the treatment of fatigue in China. The aim of this review was to summarize the efficacy of adjuvant therapy with CHM Huangqi (CHM-HQ) in managing fatigue after stroke. We searched the databases in both English and Chinese for randomized controlled trials (RCTs) on CHM-HQ for PSF till November 2016. The Cochrane risk of bias tool was used to assess the quality of included trials, and the Review Manager 5.3 software was used to conduct the data analysis. Sixteen RCTs with a total of 1222 participants were included. The evidence was poor in quality with unclear or high risks of bias. Compared to routine intervention, treatment with CHM-HQ decreased the fatigue severity based on the assessment of the Fatigue Severity Scale, Fugl-Meyer and Visual Analogue Scale, and improved the quality of life as measured by the Stroke Specific Quality of Life scale, the Barthel index, and the modified Barthel index, while the adverse effects were mild. In conclusions, adjuvant therapy with CHM-HQ may benefit in managing fatigue and quality of life in stroke patients. However, stronger evidence is needed for a promising conclusion and more rigorous designs of RCTs are merited in the future.


Assuntos
Astragalus propinquus , Quimioterapia Adjuvante/métodos , Medicamentos de Ervas Chinesas/administração & dosagem , Fadiga/tratamento farmacológico , Acidente Vascular Cerebral/tratamento farmacológico , Fadiga/etiologia , Fadiga/psicologia , Humanos , Medicina Tradicional Chinesa/métodos , Qualidade de Vida/psicologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/psicologia
17.
Environ Monit Assess ; 192(2): 103, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31915995

RESUMO

Solar ultraviolet (UV) radiation exhibits a significant degradation for dissolved organic matter (DOM) in natural water ecosystems. However, research on photodegradation process of terrestrial components (e.g., humic-like substances) of DOM are limited due to drastic water dilution and rapid degradation. Here, photochemical degradation of terrestrial soil DOM with abundant humic-like substances from different land use were investigated by utilizing spectral technologies. Simulated UV radiation caused obvious losses on concentration, component structures, and fluorescence characteristic of soil DOM samples. The correlations between absorption specific parameters (a280, SUVA254, and SR) and dissolved organic carbon (DOC) were especially pronounced (p < 0.05), which could be used as valid indicators to determine changes in DOM composition and molecular size during photobleaching process. The decreases of DOM fluorescence intensity were corresponded to first-order kinetic and half-life reactions. The greatest reduction on fluorescence intensity (31.56-81.97%) belonged to peak C (i.e., humic-like substances). Overall, DOM from forest and grass soil ecosystems was more easily photochemical degraded than anthropogenic soil DOM. Enhancive contribution of fresh DOM formed by photodegradation increased autochthonous characteristic and bioavailable nutrition by increasing biological index (BIX) values and ammonia nitrogen (NH4+-N) concentration. The slight microbial decomposition effects on DOM happened in unsterilized dark condition. Our findings provided insights for understanding the rapid photodegradation processes of composition and structure of terrestrial DOM. Graphical abstract.


Assuntos
Substâncias Húmicas/efeitos da radiação , Compostos Orgânicos/efeitos da radiação , Solo/química , Raios Ultravioleta , Ecossistema , Monitoramento Ambiental , Fluorescência , Substâncias Húmicas/análise , Compostos Orgânicos/química , Fotólise
18.
Mol Cancer ; 18(1): 181, 2019 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-31823788

RESUMO

BACKGROUND: Brain metastasis (BM) is one of the principal causes of mortality for lung cancer patients. While the molecular events that govern BM of lung cancer remain frustrating cloudy. METHODS: The miRNA expression profiles are checked in the paired human BM and primary lung cancer tissues. The effect of miR-143-3p on BM of lung cancer cells and its related mechanisms are investigated. RESULTS: miR-143-3p is upregulated in the paired BM tissues as compared with that in primary cancer tissues. It can increase the invasion capability of in vitro blood brain barrier (BBB) model and angiogenesis of lung cancer by targeting the three binding sites of 3'UTR of vasohibin-1 (VASH1) to inhibit its expression. Mechanistically, VASH1 can increase the ubiquitylation of VEGFA to trigger the proteasome mediated degradation, further, it can endow the tubulin depolymerization through detyrosination to increase the cell motility. m6A methyltransferase Mettl3 can increase the splicing of precursor miR-143-3p to facilitate its biogenesis. Moreover, miR-143-3p/VASH1 axis acts as adverse prognosis factors for in vivo progression and overall survival (OS) rate of lung cancer. CONCLUSIONS: Our work implicates a causal role of the miR-143-3p/VASH1 axis in BM of lung cancers and suggests their critical roles in lung cancer pathogenesis.


Assuntos
Adenosina/análogos & derivados , Neoplasias Encefálicas/secundário , Proteínas de Ciclo Celular/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , MicroRNAs/genética , Animais , Barreira Hematoencefálica/metabolismo , Linhagem Celular Tumoral , Modelos Animais de Doenças , Progressão da Doença , Transição Epitelial-Mesenquimal/genética , Perfilação da Expressão Gênica , Humanos , Neoplasias Pulmonares/metabolismo , Camundongos , Modelos Biológicos , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Interferência de RNA , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Mol Cancer ; 18(1): 7, 2019 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-30626401

RESUMO

Understanding of intratumor heterogeneity (ITH) among different non-small cell lung cancer (NSCLC) subtypes is necessary. Whether circulating tumor DNA (ctDNA) profile could represent these ITH is still an open question. We performed 181 multi-region tumor tissues sequencing and matched ctDNA sequencing from 32 operative NSCLC to compare ITH among different NSCLC subtypes, including EGFR-mutant lung adenocarcinoma (LUAD), KRAS-mutant LUAD, EGFR&KRAS-wild-type LUAD, and lung squamous cell carcinoma (LUSC), and examine potential value of ctDNA for ITH analysis. ITH is evaluated by ITH index (ITHi). If the somatic genetic alteration is shared by all the tissue regions, it is defined as trunk mutation. Otherwise, it is called branch mutation. The ITHi will be higher, if the tumor has less trunk mutations. We found EGFR-mutant LUAD showed significantly higher ITHi than KRAS-mutant LUAD/wild-type LUAD (P = 0.03) and numerically higher ITH than LUSC. For trunk mutations, driver mutations were identified at a higher proportion than passenger mutations (60% vs. 40%, P = 0.0023) in overall, especially in EGFR-mutant LUAD (86% vs. 14%, P = 0.0004), while it was opposite in KRAS-mutant LUAD (40% vs. 60%, P = 0.18). For branch mutations, the proportions of driver mutations and passenger mutations were similar for each NSCLC subtype. ctDNA analysis showed unsatisfactory detections of tumor-derived trunk and branch mutations (43% vs. 23%, P = 4.53e-6) among all NSCLC subtypes. In summary, EGFR-mutant LUAD has the highest ITH than other NSCLC subtypes, offering further understanding of tumorigenesis mechanisms among different NSCLC subtypes. Besides, ctDNA maybe not an appropriate method to reflect ITH.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , DNA Tumoral Circulante/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , DNA de Neoplasias/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos
20.
Cancer ; 125(20): 3535-3544, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31287555

RESUMO

BACKGROUND: Patients with brain metastases (BMs) have a poor prognosis and limited therapeutic options. Lung cancer is the most common primary malignancy giving rise to BMs; thus, understanding the molecular mechanisms behind increased BM risk is essential for identifying therapeutic targets and developing effective interventions. METHODS: Sixty-one patients who underwent surgical resection of primary non-small cell lung cancer (NSCLC) and BMs were retrospectively studied. Comprehensive genomic profiling of primary NSCLC and matched BMs was performed with next-generation sequencing targeting 416 cancer-relevant genes. RESULTS: Mutations of major drivers, including EGFR, KRAS, TP53, and ALK, were highly concordant between primary NSCLC and matched BMs (>80%), whereas discordance suggested the unique genomic evolution and oncogenic mechanisms of NSCLC BMs. BMs also demonstrated higher levels of copy number variations in comparison with primary NSCLC. Furthermore, the alterations of genes encoding CDK4/CCND1, CDKN2A/2B, and PI3K signaling pathways were enriched in BMs, and this suggested their correlation with increased metastatic risk. Indeed, patients with activated PI3K signaling in their primary NSCLC had significantly shorter BM-free survival (hazard ratio, 8.49; P = .0005). In addition, mutated TP53 or an activated WNT pathway via CTNNB1, APC, and AXIN2 mutations trended toward shorter BM-free intervals but not significantly so. CONCLUSIONS: These findings yield detailed insights into the genomic complexity and heterogeneity of primary NSCLC and matched BMs. This study highlights the significant correlation of PI3K signaling with increased metastatic risk in patients with NSCLC and identifies genomic alterations enriched in NSCLC BMs that could serve as prognostic markers and potential therapeutic targets for treating patients with NSCLC BMs.


Assuntos
Neoplasias Encefálicas/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Proteínas de Neoplasias/genética , Transcriptoma/genética , Adulto , Idoso , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/cirurgia , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Ciclina D1/genética , Quinase 4 Dependente de Ciclina/genética , Inibidor de Quinase Dependente de Ciclina p15/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Variações do Número de Cópias de DNA/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Instabilidade Genômica/genética , Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Metástase Neoplásica , Estudos Retrospectivos
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