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1.
Histol Histopathol ; : 18676, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37997936

RESUMO

Ahead of Print article withdrawn by publisher. This article has been withdrawn at the request of the author(s). The authors have found some mistakes that could affert the conclusion. The publisher apologizes for any inconvenience this may cause.

2.
Fitoterapia ; 164: 105359, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36423883

RESUMO

Three new spirocyclic polyketides, talaromyacins A - C, were identified from the endophytic fungus Talaromyces sp. CX11. Their structures including absolute configurations were determined by extensive spectroscopic analysis, Snatzke's method and quantum chemical calculations. Talaromyacin A is identical to the known sequoiamonascin A, for which a structural revision is required.


Assuntos
Policetídeos , Talaromyces , Estrutura Molecular , Talaromyces/química , Policetídeos/química
3.
Nature ; 609(7925): 46-51, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36045238

RESUMO

Superlattices-a periodic stacking of two-dimensional layers of two or more materials-provide a versatile scheme for engineering materials with tailored properties1,2. Here we report an intrinsic heterodimensional superlattice consisting of alternating layers of two-dimensional vanadium disulfide (VS2) and a one-dimensional vanadium sulfide (VS) chain array, deposited directly by chemical vapour deposition. This unique superlattice features an unconventional 1T stacking with a monoclinic unit cell of VS2/VS layers identified by scanning transmission electron microscopy. An unexpected Hall effect, persisting up to 380 kelvin, is observed when the magnetic field is in-plane, a condition under which the Hall effect usually vanishes. The observation of this effect is supported by theoretical calculations, and can be attributed to an unconventional anomalous Hall effect owing to an out-of-plane Berry curvature induced by an in-plane magnetic field, which is related to the one-dimensional VS chain. Our work expands the conventional understanding of superlattices and will stimulate the synthesis of more extraordinary superstructures.

4.
Nano Lett ; 21(12): 5338-5344, 2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34105969

RESUMO

FeTe1-xSex, a promising layered material used to realize Majorana zero modes, has attracted enormous attention in recent years. Pulsed laser deposition (PLD) and molecular-beam epitaxy (MBE) are the routine growth methods used to prepare FeTe1-xSex thin films. However, both methods require high-vacuum conditions and polished crystalline substrates, which hinder the exploration of the topological superconductivity and related nanodevices of this material. Here we demonstrate the growth of the ultrathin FeTe1-xSex superconductor by a facile, atmospheric pressure chemical vapor deposition (CVD) method. The composition and thickness of the two-dimensional (2D) FeTe1-xSex nanosheets are well controlled by tuning the experimental conditions. The as-prepared FeTe0.8Se0.2 nanosheet exhibits an onset superconducting transition temperature of 12.4 K, proving its high quality. Our work offers an effective strategy for preparing the ultrathin FeTe1-xSex superconductor, which could become a promising platform for further study of the unconventional superconductivity in the FeTe1-xSex system.

5.
Lancet Oncol ; 22(5): 716-726, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33857411

RESUMO

BACKGROUND: Cisplatin-based induction chemotherapy plus concurrent chemoradiotherapy in the treatment of patients with locoregionally advanced nasopharyngeal carcinoma has been recommended in the National Comprehensive Cancer Network Guidelines. However, cisplatin is associated with poor patient compliance and has notable side-effects. Lobaplatin, a third-generation platinum drug, has shown promising antitumour activity against several malignancies with less toxicity. In this study, we aimed to evaluate the efficacy of lobaplatin-based induction chemotherapy plus concurrent chemoradiotherapy over a cisplatin-based regimen in patients with locoregional, advanced nasopharyngeal carcinoma. METHODS: In this open-label, non-inferiority, randomised, controlled, phase 3 trial done at five hospitals in China, patients aged 18-60 years with previously untreated, non-keratinising stage III-IVB nasopharyngeal carcinoma; Karnofsky performance-status score of at least 70; and adequate haematological, renal, and hepatic function were randomly assigned (1:1) to receive intravenously either lobaplatin-based (lobaplatin 30 mg/m2 on days 1 and 22, and fluorouracil 800 mg/m2 on days 1-5 and 22-26 for two cycles) or cisplatin-based (cisplatin 100 mg/m2 on days 1 and 22, and fluorouracil 800 mg/m2 on days 1-5 and 22-26 for two cycles) induction chemotherapy, followed by concurrent lobaplatin-based (two cycles of intravenous lobaplatin 30 mg/m2 every 3 weeks plus intensity-modulated radiotherapy) or cisplatin-based (two cycles of intravenous cisplatin 100 mg/m2 every 3 weeks plus intensity-modulated radiotherapy) chemoradiotherapy. Total radiation doses of 68-70 Gy (for the sum of the volumes of the primary tumour and enlarged retropharyngeal nodes), 62-68 Gy (for the volume of clinically involved gross cervical lymph nodes), 60 Gy (for the high-risk target volume), and 54 Gy (for the low-risk target volume), were administered in 30-32 fractions, 5 days per week. Randomisation was done centrally at the clinical trial centre of Sun Yat-sen University Cancer Centre by means of computer-generated random number allocation with a block design (block size of four) stratified according to disease stage and treatment centre. Treatment assignment was known to both clinicians and patients. The primary endpoint was 5-year progression-free survival, analysed in both the intention-to-treat and per-protocol populations. If the upper limit of the 95% CI for the difference in 5-year progression-free survival between the lobaplatin-based and cisplatin-based groups did not exceed 10%, non-inferiority was met. Adverse events were analysed in all patients who received at least one cycle of induction chemotherapy. This trial is registered with the Chinese Clinical Trial Registry, ChiCTR-TRC-13003285 and is closed. FINDINGS: From June 7, 2013, to June 16, 2015, 515 patients were assessed for eligibility and 502 patients were enrolled: 252 were randomly assigned to the lobaplatin-based group and 250 to the cisplatin-based group. After a median follow-up of 75·3 months (IQR 69·9-81·1) in the intention-to-treat population, 5-year progression-free survival was 75·0% (95% CI 69·7-80·3) in the lobaplatin-based group and 75·5% (70·0 to 81·0) in the cisplatin-based group (hazard ratio [HR] 0·98, 95% CI 0·69-1·39; log-rank p=0·92), with a difference of 0·5% (95% CI -7·1 to 8·1; pnon-inferiority=0·0070). In the per-protocol population, the 5-year progression-free survival was 74·8% (95% CI 69·3 to 80·3) in the lobaplatin-based group and 76·4% (70·9 to 81·9) in the cisplatin-based group (HR 1·04, 95% CI 0·73 to 1·49; log-rank p=0·83), with a difference of 1·6% (-6·1 to 9·3; pnon-inferiority=0·016). 63 (25%) of 252 patients in the lobaplatin-based group and 63 (25%) of 250 patients in the cisplatin-based group had a progression-free survival event in the intention-to-treat population; 62 (25%) of 246 patients in the lobaplatin-based group and 58 (25%) of 237 patients in the cisplatin-based group had a progression-free survival event in the per-protocol population. The most common grade 3-4 adverse events were mucositis (102 [41%] of 252 in the lobaplatin-based group vs 99 [40%] of 249 in the cisplatin-based group), leucopenia (39 [16%] vs 56 [23%]), and neutropenia (25 [10%] vs 59 [24%]). No treatment-related deaths were reported. INTERPRETATION: Lobaplatin-based induction chemotherapy plus concurrent chemoradiotherapy resulted in non-inferior survival and fewer toxic effects than cisplatin-based therapy. The results of our trial indicate that lobaplatin-based induction chemotherapy plus concurrent chemoradiotherapy might be a promising alternative regimen to cisplatin-based treatment in patients with locoregional, advanced nasopharyngeal carcinoma. FUNDING: National Science and Technology Pillar Program, International Cooperation Project of Science and Technology Program of Guangdong Province, Planned Science and Technology Project of Guangdong Province, and Cultivation Foundation for the Junior Teachers at Sun Yat-sen University. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimiorradioterapia , Carcinoma Nasofaríngeo/terapia , Neoplasias Nasofaríngeas/terapia , Adulto , Ciclobutanos/administração & dosagem , Ciclobutanos/efeitos adversos , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Humanos , Quimioterapia de Indução , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/mortalidade , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/patologia , Estadiamento de Neoplasias , Compostos Organoplatínicos/administração & dosagem , Compostos Organoplatínicos/efeitos adversos , Dosagem Radioterapêutica
6.
Org Lett ; 21(16): 6539-6542, 2019 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-31364857

RESUMO

Talaromyolides A-D (1-4) and talaromytin (5) were isolated from a marine fungus Talaromyces sp. CX11. Their structures were unambiguously determined by nuclear magnetic resonance (NMR), mass spectrometry, X-ray crystallography experiments, and time-dependent density functional theory electronic circular dichroism calculations. Talaromyolides A and D represent two novel carbon skeletons. Talaromytin exhibits two slowly interconverting conformers in DMSO-d6 and CH3OH-d4 that were studied by temperature-dependent NMR experiments. Talaromyolide D exhibits potent antiviral activity against pseudorabies virus (PRV) with a CC50 value of 3.35 µM.


Assuntos
Antivirais/farmacologia , Talaromyces/química , Terpenos/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Antivirais/química , Linhagem Celular Tumoral , Dicroísmo Circular , Cristalografia por Raios X , Teoria da Densidade Funcional , Avaliação Pré-Clínica de Medicamentos , Herpesvirus Suídeo 1/efeitos dos fármacos , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Talaromyces/metabolismo , Terpenos/farmacologia
7.
Huan Jing Ke Xue ; 36(7): 2504-10, 2015 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-26489318

RESUMO

In order to study the coupling effects of decomposed Potamogeton crispus (P. crispus) and growing Ceratophyllum demersum (C. demersum) on water quality and the effects of different decomposed biomass on plant growth, the simulating experiments for seasonal changes of submerged macrophytes were conducted. The results indicated that the nutrient concentrations in water remained at a relatively low level with different decomposed biomass and they remained stable after 29 days of the experiment. The concentrations of total dissolved nitrogen (DTN), total nitrogen (TN), total phosphorous (TP), total dissolved phosphorous (DTP), organic carbon (TOC) and chlorophyll-a (Chl-a) were lower than 0. 514, 0. 559, 0. 080, 0. 014, 13. 94 and 26. 546 mg . L-1, respectively. The obvious improving effects on water quality were observed under coupling condition of decomposition and growth, especially when the treatment of decomposed P. crispus was 20 g, and the removal efficiency of TN, DTN, TP, DTP, TOC and Chl-a reached 89. 67% , 52. 51%, 94. 99%, 55. 59% and 98. 55%, respectively. Compared with the physiology of C. demersum in the early stage, the contents of total chlorophyll, soluble protein and malondialdehyde all increased under different decomposed biomass conditions, which suggested that the nutrient released from decomposed P. crispus promoted the growth of C. demersum. The coupling effects between P. crispus decomposition and C. demersum growth showed better improving effect on water quality and growth of C. demersum with treatment of 20 g decomposed P. crispus.


Assuntos
Magnoliopsida/crescimento & desenvolvimento , Potamogetonaceae , Qualidade da Água , Água/química , Biomassa , Carbono/análise , Clorofila/análise , Clorofila A , Nitrogênio/análise , Fósforo/análise
8.
J Neuroeng Rehabil ; 12: 73, 2015 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-26311232

RESUMO

BACKGROUND: Epiretinal prostheses have been greatly successful in helping restore the vision of patients blinded by retinal degenerative diseases. The design of stimulating electrodes plays a crucial role in the performance of epiretinal prostheses. The objective of this study was to investigate, through computational modeling analysis, the effects on the excitation of retinal ganglion cells (RGCs) when different three-dimensional (3-D) electrodes were placed in the epiretinal space. METHODS: 3-D finite element models of retinal electrical stimulation were created in COMSOL using a platinum microelectrode, a vitreous body, multi-layered retinal tissue, and retinal pigment epithelium (RPE). Disk and non-planar electrodes with different 3-D structures were used in the epiretinal electrical stimulation. In addition, a multi-RGC model including ionic mechanisms was constructed in NEURON to study the excitability of RGCs in response to epiretinal electrical stimulation by different types of electrodes. Threshold current, threshold charge density, and the activated RGC area were the three key factors used to evaluate the stimulating electrode's performance. RESULTS: As the electrode-retina distance increased, both threshold current and threshold charge density showed an approximately linear relationship. Increasing the disk electrode's diameter resulted in an increase in threshold current and a decrease in threshold charge density. Non-planar electrodes evoked different activation responses in RGCs than the disk electrode. Concave electrodes produced superior stimulation localization and electrode safety while convex electrodes performed relatively poorly. CONCLUSIONS: Investigation of epiretinal electrical stimulation using different 3-D electrodes would further the optimization of electrode design and help improve the performance of epiretinal prostheses. The combination of finite element analysis in COMSOL and NEURON software provides an efficient way to evaluate the influences of various 3-D electrodes on epiretinal electrical stimulation. Non-planar electrodes had larger threshold currents than disk electrodes. Of the five types of electrodes, concave hemispherical electrodes may be the ideal option, considering their superior stimulation localization and electrode safety.


Assuntos
Terapia por Estimulação Elétrica/instrumentação , Terapia por Estimulação Elétrica/métodos , Eletrodos , Retina , Algoritmos , Simulação por Computador , Terapia por Estimulação Elétrica/efeitos adversos , Eletrodos/efeitos adversos , Análise de Elementos Finitos , Humanos , Potenciais da Membrana , Modelos Neurológicos , Modelos Teóricos , Próteses Neurais , Desenho de Prótese , Retina/anatomia & histologia , Células Ganglionares da Retina/fisiologia
9.
J Ethnopharmacol ; 157: 62-8, 2014 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-25260580

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Nirtetralin B, a new lignan first reported by our team, is isolated from Phyllanthus niruri L. This plant has long been used in folk medicine for liver protection and antihepatitis B in many Asian countries. This study was designed to evaluate the anti-hepatitis B virus activity of nirtetralin B using HepG2.2.15 cells and duck hepatitis B virus (DHBV) infected ducks as in vitro and in vivo models. MATERIALS AND METHODS: Nirtetralin B was isolated from Phyllanthus niruri L. (Euphorbiaceae) by extraction and chromatographic procedures and the anti-hepatitis B virus activity was evaluated both in vitro and in vivo. The human HBV-transfected liver cell line HepG2.2.15 was used in vitro assay. And the in vivo anti-hepatitis B virus activity was evaluated on the expression of HBV replication, HBsAg, HBeAg, ALT and AST on day 0, 7, 14, 17 after nirtetralin B was dosed intragastricly (i.g.) once a day for 14 days at the dosages of 25, 50 and 100mg/kg/day in the duck hepatitis B virus (DHBV) infected ducks. RESULTS: In the human HBV-transfected liver cell line HepG2.2.15, nirtetralin B effectively suppressed the secretion of the HBV antigens in a dose-dependent manner with IC50 values for HBsAg of 17.4µM, IC50 values for HBeAg of 63.9µM. In DHBV-infected ducklings, nirtetralin B significantly reduced the serum DHBV DNA, HBsAg, HBeAg, ALT and AST. And analysis of the liver pathological changes confirmed the hepatoprotective effect of nirtetralin B. CONCLUSION: The experimental data demonstrated that nirtetralin B exhibits anti-hepatitis B virus activity both in vitro and in vivo.


Assuntos
Anisóis/farmacologia , Antivirais/farmacologia , Dioxóis/farmacologia , Hepatite B/tratamento farmacológico , Lignanas/farmacologia , Phyllanthus/química , Animais , Anisóis/administração & dosagem , Anisóis/isolamento & purificação , Antivirais/administração & dosagem , Antivirais/isolamento & purificação , Dioxóis/administração & dosagem , Dioxóis/isolamento & purificação , Relação Dose-Resposta a Droga , Patos , Feminino , Células Hep G2 , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B do Pato/efeitos dos fármacos , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Lignanas/administração & dosagem , Lignanas/isolamento & purificação , Masculino , Medicina Tradicional , Replicação Viral/efeitos dos fármacos
10.
J Ethnopharmacol ; 155(2): 1061-7, 2014 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-25009077

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Niranthin is a lignan isolated from Phyllanthus niruri L. This plant has long been used in folk medicine for liver protection and antihepatitis B in many Asian countries. This study was designed to evaluate the anti-hepatitis B virus activity of niranthin using HepG2.2.15 cells and duck hepatitis B virus (DHBV) infected ducks as in vitro and in vivo models. MATERIALS AND METHODS: Niranthin was isolated from Phyllanthus niruri L. (Euphorbiaceae) by extraction and chromatographic procedures and the anti-hepatitis B virus activity was evaluated both in vitro and in vivo. The human HBV-transfected liver cell line HepG2.2.15 was used in vitro assay. And the in vivo anti-hepatitis B virus activity was evaluated on the expression of HBV replication, HBsAg, HBeAg, ALT and AST on day 0, 7, 14, 17 after niranthin was dosed intragastricly (i.g.) once a day for 14 days at the dosages of 25, 50 and 100 mg/kg/day in the duck hepatitis B virus (DHBV) infected ducks. RESULTS: In the human HBV-transfected liver cell line HepG2.2.15, the secretion of HBsAg and HBeAg were significantly decreased after treatment with niranthin for 144 h, with IC50 values for HBsAg of 15.6 µM, IC50 values for HBeAg of 25.1 µM. In DHBV-infected ducklings, niranthin significantly reduced the serum DHBV DNA, HBsAg, HBeAg, ALT and AST. Furthermore, analysis of the liver pathological changes confirmed the hepatoprotective effect of niranthin. CONCLUSION: The experimental data demonstrated that niranthin exhibits anti-hepatitis B virus activity both in vitro and in vivo.


Assuntos
Anisóis/farmacologia , Antivirais/farmacologia , Dioxóis/farmacologia , Vírus da Hepatite B/efeitos dos fármacos , Phyllanthus/química , Animais , Anisóis/administração & dosagem , Anisóis/isolamento & purificação , Antivirais/administração & dosagem , Antivirais/isolamento & purificação , Dioxóis/administração & dosagem , Dioxóis/isolamento & purificação , Modelos Animais de Doenças , Patos , Feminino , Células Hep G2 , Infecções por Hepadnaviridae/tratamento farmacológico , Infecções por Hepadnaviridae/virologia , Hepatite B/tratamento farmacológico , Antígenos de Superfície da Hepatite B/metabolismo , Vírus da Hepatite B do Pato/efeitos dos fármacos , Antígenos E da Hepatite B/metabolismo , Hepatite Viral Animal/tratamento farmacológico , Hepatite Viral Animal/virologia , Humanos , Concentração Inibidora 50 , Lignanas/administração & dosagem , Lignanas/isolamento & purificação , Lignanas/farmacologia , Masculino
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