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1.
BMC Gastroenterol ; 23(1): 231, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37420205

RESUMO

BACKGROUND: Helicobacter pylori infection and associated diseases are a growing global public health issue. H. pylori infection is the major cause of gastric cancer, over 90% of duodenal ulcers, and over 70% of gastric ulcers. The infection rate of H. pylori is approximately 50%, and approximately 50% of new cases of gastric cancer worldwide occur in China. Bismuth (BI)-based quadruple therapy is recommended as the first-line treatment for H. pylori in China. Vonoprazan (VPZ), a new potassium-competitive acid blocker that can inhibit gastric acid secretion more effectively than proton pump inhibitors (PPIs), has been combined with antibiotics to effectively eradicate H. pylori. In this study, we compared the efficacy and safety of two VPZ-based therapies with that of BI-based therapy for H. pylori treatment. METHODS: A three-armed randomised controlled trial (RCT) is being conducted in Shenzhen, with 327 participants recruited from the Gastroenterology Clinic of the University of Hong Kong-Shenzhen Hospital. Patients were diagnosed with H. pylori infection based on a positive 13C-urea breath test (UBT). Patients are kept naïve to their treatment and are randomly assigned in a 1:1:1 ratio to either VPZ-based triple, VPZ-based dual, or BI-based quadruple therapy for 14 days. All groups are subjected to follow-up evaluations of safety, adverse drug reactions, and clinical variables in the first, second, and fourth weeks after treatment. Successful eradication is confirmed by a negative 13C-UBT six weeks after treatment. If initial treatment fails, (1) those patients are turned to another regimen, or (2) a drug resistance test is conducted, after which an individualised treatment regimen shall be prescribed according to antimicrobial susceptibility testing. The resulting data will be evaluated using intention-treat and a per-protocol analysis. DISCUSSION: This study is the a RCT aims to evaluate the efficacy and safety of 14-day VPZ-based triple and dual therapies in comparison with BI-based quadruple therapy. The outcomes of this study may allow treatment recommendations and update drug instructions in China. TRIAL REGISTRATION: Chinese Clinical Trial Registry (No. ChiCTR2200056375). Registered on February 4, 2022, https://www.chictr.org.cn/showproj.aspx?proj=141314.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Humanos , Bismuto/efeitos adversos , Neoplasias Gástricas/tratamento farmacológico , Quimioterapia Combinada , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/diagnóstico , Antibacterianos/efeitos adversos , Inibidores da Bomba de Prótons/efeitos adversos , Amoxicilina/efeitos adversos , Resultado do Tratamento , Claritromicina/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto
2.
Adv Sci (Weinh) ; 10(25): e2301713, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37381645

RESUMO

Conductive hydrogels exhibit high potential in the fields of wearable sensors, healthcare monitoring, and e-skins. However, it remains a huge challenge to integrate high elasticity, low hysteresis, and excellent stretch-ability in physical crosslinking hydrogels. This study reports the synthesis of polyacrylamide (PAM)-3-(trimethoxysilyl) propyl methacrylate-grafted super arborized silica nanoparticle (TSASN)-lithium chloride (LiCl) hydrogel sensors with high elasticity, low hysteresis, and excellent electrical conductivity. The introduction of TSASN enhances the mechanical strength and reversible resilience of the PAM-TSASN-LiCl hydrogels by chain entanglement and interfacial chemical bonding, and provides stress-transfer centers for external-force diffusion. These hydrogels show outstanding mechanical strength (a tensile stress of 80-120 kPa, elongation at break of 900-1400%, and dissipated energy of 0.8-9.6 kJ m-3 ), and can withstand multiple mechanical cycles. LiCl addition enables the PAM-TSASN-LiCl hydrogels to exhibit excellent electrical properties with an outstanding sensing performance (gauge factor = 4.5), with rapid response (210 ms) within a wide strain-sensing range (1-800%). These PAM-TSASN-LiCl hydrogel sensors can detect various human-body movements for prolonged durations of time, and generate stable and reliable output signals. The hydrogels fabricated with high stretch-ability, low hysteresis, and reversible resilience, can be used as flexible wearable sensors.

3.
Nat Prod Res ; 36(8): 1980-1987, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33121294

RESUMO

Two new phenylpropanoid glycosidic compounds (a pair of epimers), named pleionosides K (1) and L (2), were isolated from the pseudobulbs of Pleione bulbocodioides (Franch.) Rolfe. Their structures, including absolute configurations, were elucidated by a combination of MS, NMR data, chemical methods and the comparison of experimental and calculated electronic circular dichroism (ECD). Their possible biosynthetic pathway was discussed in the text. Furthermore, the two compounds exhibited moderate hepatoprotective activity against N-acetyl-p-aminophenol (APAP)-induced HepG2 cell damage in in vitro assays, with cell survival rates of 25.83% and 28.82% at 10 µM, respectively, and antioxidant effect against H2O2-induced toxicity in human SK-N-SH cell, with increasing viability at 10 µM of 24.9% and 34.6%, respectively.


Assuntos
Peróxido de Hidrogênio , Orchidaceae , Glicosídeos/química , Glicosídeos/farmacologia , Células Hep G2 , Humanos , Peróxido de Hidrogênio/farmacologia , Estrutura Molecular , Orchidaceae/química
4.
J Nat Prod ; 84(3): 738-749, 2021 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-33606538

RESUMO

Nine new glucosyloxybenzyl 2-hydroxy-2-isobutylsuccinates, pleionosides M-U (1-9), and 12 known compounds (10-21) were isolated from the pseudobulbs of Pleione yunnanensis. Their structures and absolute configurations were established through a combination of HRESIMS and NMR data and supported by physical and chemical methods. Compounds 5, 6, 10, and 15 showed significant in vitro hepatoprotective activity against d-galactosamine (d-GalN)-induced toxicity in HL-7702 cells with increasing cell viability by 27%, 22%, 19%, and 31% compared to the model group (cf. bicyclol, 14%) at 10 µM, respectively. Compounds 4, 9, and 11 exhibited moderate hepatoprotective activity against N-acetyl-p-aminophenol (APAP)-induced toxicity in HepG2 cells with increasing cell viability by 9%, 16%, and 12% compared to the model group (cf. bicyclol, 9%) at 10 µM, respectively.


Assuntos
Orchidaceae/química , Substâncias Protetoras/farmacologia , Succinatos/farmacologia , Acetaminofen , Sobrevivência Celular/efeitos dos fármacos , China , Células Hep G2 , Humanos , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Substâncias Protetoras/isolamento & purificação , Succinatos/isolamento & purificação
5.
Phytochemistry ; 182: 112609, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33326906

RESUMO

Thirteen undescribed phenanthrene and bibenzyl derivatives, named blestanols A-M, including one pair of biphenanthrene enantiomers, two bis 9,10-dihydrophenanthrene ethers, five pairs of 9,10-dihydrophenanthrene/bibenzyl atropisomers, one racemic 9,10-dihydrophenanthrene/bibenzyl dimer, one 9,10-dihydrophenanthrenebibenzyl ether, two pairs of bibenzyl derivatives, and one stilbene, together with 12 known analogues were isolated from the tubers of Bletilla striata. The structures were elucidated via spectroscopic data analysis. 15 compounds were purified to yield enantiomers (a, b) via chiral-phase HPLC, and their configurations were determined by optical rotation values and the comparison of the experimental and calculated electronic circular dichroism (ECD) curves. Blestanols K-L possessed a cycloheptene moiety, which is rarely observed in bibenzyl derivatives. A putative biosynthetic pathway for the identified components is deduced. Among these compounds, 14 compounds showed inhibition of NO production, with IC50 values ranging from 5.0 to 19.0 µM. Eight compounds displayed selective cytotoxic activities against HCT-116, HepG2, BGC-823, A549 or U251 cancer cell lines, with IC50 values ranging from 1.4 to 8.3 µM. In addition, their structure-activity relationships are discussed briefly.


Assuntos
Bibenzilas , Orchidaceae , Fenantrenos , Bibenzilas/farmacologia , Estrutura Molecular , Fenantrenos/farmacologia , Estereoisomerismo
6.
Materials (Basel) ; 13(23)2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-33261087

RESUMO

Evolutions of two typical types of nonmetallic inclusions, i.e., inclusions based on CaO-SiO2-Al2O3 and MnO-SiO2-Al2O3 of 304 stainless steel were investigated in laboratory-scale experiments under isothermal heat treatment at 1250 °C for 0, 30, 60 and 120 min. Results show inclusion population density increases at the first stage and then decreases while their average size decreases and then increases. Moreover, almost no Cr2O3 content within the inclusion before the heat treatment, but Cr2O3 content increases gradually along with increasing heat treatment time. Furthermore, the increasing of Cr2O3 content in the inclusions would increase their melting points and reduce their plasticities. The experimental results and thermodynamic analysis indicate that there are three steps for inclusion evolution during the heat treatment process, in which Ostwald ripening plays an important role in inclusion evolution, i.e., inclusions grow by absorbing the newly formed small-size MnO-Cr2O3 inclusions.

7.
Bioorg Chem ; 104: 104312, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33142424

RESUMO

Approximately 17 compounds were isolated from a 60% EtOH aqueous extract of the roots and rhizomes of Clematis hexapetala Pall., including three new guaianolide sesquiterpenoids with 5/7/5-fused rings and 3S-configuration (1-3), five new prenylated tetra-substituted phenolic glycosides (4-8) with 6/6-fused 9H-benzopyran skeleton (5) and 6/7-fused 7,10-dihydro-benzoxepin skeleton (6-8), one new isoferulyl glucoside (9), two new furofuran lignan diglucosides (10-11), and six known compounds. The chemical structures of the new compounds were elucidated via spectroscopic data and electronic circular dichroism (ECD) analyses in combination with a modified Mosher's method. The possible biosynthetic relationships of prenylated tetra-substituted phenols were postulated. In the in vitro assays, compound 16 exhibited moderate TNF-α secretion inhibitory activity with IC50 value of 3.419 µM. Compounds 14-16 displayed potent PTP1B enzymatic inhibitory activities with inhibition ratios of 48.30-86.00%. And compound 16 showed significant PTP1B enzymatic inhibition with IC50 value of 4.623 µM.


Assuntos
Anti-Inflamatórios/farmacologia , Clematis/química , Glicosídeos/farmacologia , Lignanas/farmacologia , Fenóis/farmacologia , Rizoma/química , Sesquiterpenos/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Relação Dose-Resposta a Droga , Glicosídeos/química , Glicosídeos/isolamento & purificação , Lignanas/química , Lignanas/isolamento & purificação , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Camundongos , Estrutura Molecular , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Fenóis/química , Fenóis/isolamento & purificação , Raízes de Plantas/química , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Células RAW 264.7 , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Relação Estrutura-Atividade , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/biossíntese
8.
Fitoterapia ; 138: 104313, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31421147

RESUMO

Bulbocodioidins E-H (1-4), four pairs of undescribed racemic bi(9,10-dihydro)phenanthrene and phenanthrene/bibenzyl atropisomers, along with four known compounds (5-8) were isolated from the ethanol extract of the pseudobulbs of Pleione bulbocodioides. Their structures were established by HRESIMS and comprehensive NMR spectroscopic data analysis. Their absolute configurations were elucidated by comparison of their experimental and calculated ECD (electronic circular dichroism) curves. Furthermore, compound 4a displayed cytotoxic activity against colon cancer (HCT-116), liver cancer (HepG2), and breast cancer (MCF-7) cell lines with IC50 values of 7.6, 3.8 and 3.4 µM, respectively. Compound 6 showed cytotoxic activity against breast cancer cell lines (MCF-7) with IC50 value of 5.4 µM.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Bibenzilas/farmacologia , Orchidaceae/química , Fenantrenos/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Bibenzilas/isolamento & purificação , China , Células HCT116 , Células Hep G2 , Humanos , Células MCF-7 , Estrutura Molecular , Fenantrenos/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Raízes de Plantas/química
9.
Int J Biol Macromol ; 122: 628-635, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30391591

RESUMO

Two water-soluble polysaccharides, BSP-1 and BSP-2, were extracted and purified from the tuber of Bletilla striata. The molecular weights of BSP-1 and BSP-2 were 83.54 kDa and 12.60 kDa, respectively. The composition and proportion of BSP-1 and BSP-2 were mannose and glucose in molar ratios of 4.0:1.0 and 3.0:1.0 respectively. The two polysaccharides had a linear backbone, consisting mainly of repeating ß­1,4­linked d­mannosyl residues and ß­1,4­linked d­glucosyl residues. BSP-1 exhibited immunomodulatory effects by increasing the thymus and spleen indices of immunocompromised model mice.


Assuntos
Orchidaceae/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Tubérculos/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Animais , Fatores Imunológicos/química , Fatores Imunológicos/farmacologia , Contagem de Leucócitos , Metilação , Camundongos , Peso Molecular , Monossacarídeos/análise , Timo/imunologia
10.
Phytochemistry ; 157: 71-81, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30384089

RESUMO

Ten previously undescribed glucosyloxybenzyl succinate derivatives, pleionosides A-J, and fifteen known compounds were isolated from the pseudobulbs of Pleione bulbocodioides (Franch.) Rolfe. Their structures were elucidated by a combination of MS and NMR data, physical and chemical methods and a comparison with known compounds. Furthermore, three compounds exhibited potent hepatoprotective activity against N-acetyl-p-aminophenol (APAP)-induced HepG2 cell damage in in vitro assays, with cell survival rates of 31.89%, 31.52% and 31.97% at 10 µM. Four compounds exhibited moderate antioxidant activity with increasing viability at 10 µM of 36.1%, 45.0%, 25.5% and 20.7%.


Assuntos
Citoproteção/efeitos dos fármacos , Fígado/citologia , Fígado/efeitos dos fármacos , Orchidaceae/química , Ácido Succínico/química , Ácido Succínico/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células Hep G2 , Humanos
11.
Org Biomol Chem ; 17(3): 567-572, 2019 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-30574990

RESUMO

Eight new phenanthrenequinones (four pairs of enantiomers), named bulbocodioidins A-D (1-4), have been isolated from the ethanolic extract of tubers of Pleione bulbocodioides. Their structures, including absolute configurations, were determined by extensive NMR analysis combined with experimental and calculated ECD (electronic circular dichroism) data analyses. Compounds 1-4 possessed a 9(10)H-phenanthren-10(9)-one structure, which is a rarely reported instance from natural sources. Their possible biosynthetic pathway was discussed in the text. The cytotoxic effects of the isolated phenanthrenequinones were evaluated in several human cancer cell lines, and compounds 1a and 4a exhibited marked cytotoxic activities.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Orchidaceae/química , Fenantrenos/farmacologia , Tubérculos/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Fenantrenos/química , Fenantrenos/isolamento & purificação , Estereoisomerismo , Relação Estrutura-Atividade
13.
Sci Rep ; 8(1): 5232, 2018 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-29588460

RESUMO

In the current study, the thermodynamics of the slag-metal equilibrium reaction between Inconel 718 Ni-based alloy and CaF2-CaO-Al2O3-MgO-TiO2 electroslag remelting (ESR)-type slags were systematically investigated in the temperature range from 1773 to 1973 K (1500 to 1700 °C). The equilibrium Al content increased with increasing temperature, whereas the equilibrium Ti content decreased with increasing temperature at a fixed slag composition. The important factors for controlling the oxidation of Al and Ti in the Inconel 718 superalloy were TiO2 > Al2O3 > CaO > CaF2 > MgO in ESR-type slag and Al > Ti in a consumable electrode. The conventional method of sampling by means of a quartz tube could result in contamination of the molten metal and changes in the size of the "special reaction interface". Therefore, a novel method was used in the present study to investigate the slag-metal reaction kinetics to accurately obtain the kinetic parameters. The mass transfer coefficient was determined by coupling with the kinetic model derived from the assumption that the reaction rate ([Al] + (TiO2) = [Ti] + (Al2O3)) was controlled by the mass transfer of [Ti], [Al], (TiO2) and (Al2O3) in the boundary layer, respectively.

14.
Zhongguo Zhong Yao Za Zhi ; 42(8): 1578-1584, 2017 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-29071865

RESUMO

Eighteen compounds were isolated from the EtOAc soluble fraction of Bletilla striata by various chromatographic techniques, such as silica gel, ODS, Sephadex LH-20, RP-HPLC. Their structures were identified by spectroscopic methods and physicochemical properties, as 5-hydroxy-2-(p-hydroxybenzyl)- 3- methoxybibenzyl(1), shancigusins B(2), shanciguol(3),arundinan(4), 3',5-dihydroxy-2,4-di(p-hydroxybenzyl)-3-methoxybibenzyl(5), arundin(6), 3,3'-dihydroxy-2-(p-hydroxybenzyl)-5-methoxybibenzyl(7), 3, 3'-dihydroxy-2', 6'-bis(p-hydroxybenzyl)-5-methoxybibenzyl(8), 7-hydroxy-2,4-dimethoxyphenanthrene(9), bleformin B(10),nudol(11), 3,7-dihydroxy-2, 4-dimethoxyphenanthrene(12), 2, 7-dihydroxy-4-methoxy-9,10-dihydrophenathrene(13), bleformin D(14), 4,4'-dimethoxy-9,10-dyhydro-[6,1'-biphenanthrene]-2,2',7,7'-tetraol(15),gymconopin C(16),(2,3-trans)-2-(4-hydroxy-3-methoxyphenyl)-3-hydroxymethyl-10-methoxy-2,3,4,5-tetrahydro-phenanthro[2,1-b]furan-7-ol(17),shanciol(18). Among them, compound 1 was a new compound, Compounds 2-6,9,15-18 were isolated from this genus for the first time.


Assuntos
Orchidaceae/química , Compostos Fitoquímicos/análise , Tubérculos/química
15.
Zhongguo Zhong Yao Za Zhi ; 40(5): 908-14, 2015 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-26087555

RESUMO

Ten glucosyloxybenzyl 2-isobutylmalates and one benzyl alcohol glycoside were isolated from the dry tuber of Pleione bulbocodioides, which is a specie of Orchidaceae family and its dry tuber is one of the main sources of traditional Chinese medicine "shanci-gu", by a combination of various column chromatographic methods, including ODS, macroporous adsorbent resin, Sepheadex LH-20, and preparative HPLC. Their structures were identified on the basis of chemical evidences and spectroscopic analysis asloroglossin (1), grammatophylloside A (2), cronupapine (3), (-)-(2R, 3S)-1-(4-ß-D-glucopyranosyloxybenzyl)-4-methyl-2-isobutyltartrate (4), vandateroside II (5), grammatophylloside B (6), bis [4-(ß-D-glucopyranosyloxy) -benzyl] (S) -2-isopropylmalate (7), gymnoside I (8), militarine (9), dactylorhin A (10), gastrodin (11). Compounds 1-7 were isolated from this genus for the firt time.


Assuntos
Medicamentos de Ervas Chinesas/química , Glucosídeos/química , Malatos/química , Orchidaceae/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Glucosídeos/isolamento & purificação , Malatos/isolamento & purificação , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray
16.
Zhongguo Zhong Yao Za Zhi ; 39(3): 442-7, 2014 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-24946545

RESUMO

Fourteen compoumds were isolated from the ethyl acetate portion of the 95% ethanolic extract of Pleione bulbocodioides by a combination of various chromatographic techniques including silica gel, ODS, macroporous adsorbent resin, Sephadex LH-20, and preparative HPLC, of which ten compoumds were phenanthrenes and dihydrophenanthrenes, two compoumds were bibenzyls, one was lignan and a sterol. Their structures were identified on the basis of spectroscopic data as monbarbatain A(1), 2, 7, 2'-trihy-droxy-4, 4', 7'-trimethoxy-1, 1'- biphenanthrene(2), blestriarene A(3), pleionesin B(4), shanciol H(5), 17-hydroxy-7'-(4'-hy-droxy-3 '-methoxyphenyl)- 4-methoxy-9, 10, 7', 8'-tetrahydrophenanthro[2, 3-b]furan-8'-yl methyl acetate(6), 1-p-hydroxybenzyl-4-methoxy phenanthrene-2, 7-diol(7), 1-p-hydroxybenzyl-4-met-hoxy-9, 10-dihydrophenanthrene-2, 7-diol(8), hircinol(9), coelonin( 10), gigantol(11), batatasin 11 (12), syringaresinol(13) and ergosta4, 6, 8 ( 14) , 22-tetraen-3-one (14). Compounds 1-3, 9, 13 and 14 were isolated from this genus for the first time.


Assuntos
Orchidaceae/química , Compostos Orgânicos/análise , Medicamentos de Ervas Chinesas/química
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