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1.
Int J Biol Macromol ; : 135764, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39299429

RESUMEN

Chronic hepatitis B virus (HBV) infection continues to pose a significant global health challenge. However, therapeutic measures for a cure are lacking in clinical practice. Manganese, an essential trace element, has garnered attention due to its potential to activate innate immune pathways and its significant role in antiviral and antitumor immunity. Yet, the specific impact of manganese on chronic hepatitis B has been largely unexplored. Our research reveals that manganese substantially inhibits HBV replication in hepatocellular carcinoma cells at non-toxic levels. This suppression occurs independently of well-known anti-HBV innate immune pathways, such as the cGAS-STING pathway. Mechanistically, manganese decreases HBV transcription by diminishing the levels of liver-specific transcription factors. Furthermore, it activates the mTOR pathway, enhancing HBsAg ubiquitination through the upregulation of the ubiquitin ligase ß-TrCP and increasing proteasome activity via the augmentation of its subunits, leading to a ubiquitin-dependent degradation of HBsAg. Significantly, our study also uncovers a notable clinical correlation between manganese levels and chronic hepatitis B infection. These findings position manganese as a critical element in diminishing HBV replication, offering a new direction in the management of chronic hepatitis B.

2.
Helicobacter ; 29(5): e13133, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39244723

RESUMEN

BACKGROUND: We compared efficacy of vonoprazan-dual or triple therapies and bismuth-quadruple therapy for treatment-naive Helicobacter pylori (HP) infection in Southern China, where primary resistance rates of clarithromycin and levofloxacin are >30%. METHODS: This was an investigator-initiated, three-arm, randomized clinical trial in Southern China. Between March 2022 and August 2023, treatment-naïve HP-infected adults were randomly assigned to receive one of three 14-day regimens (1:1:1 ratio): vonoprazan-dual (VA-dual; vonoprazan 20 mg twice daily and amoxicillin 1 g thrice daily), vonoprazan-triple (VAC-triple; vonoprazan 20 mg/amoxicillin 1 g/clarithromycin 500 mg twice daily), or bismuth-quadruple therapy containing bismuth, esomeprazole, tetracycline, and metronidazole. Primary outcome was noninferiority in HP eradication, evaluated by UBT 4-6 weeks post-treatment by intention-to-treat (ITT) and per-protocol (PP) analysis (based on subjects who completed 14-day treatment and rechecked UBT). Bonferroni-adjusted p-value of <0.017 was used to determine statistical significance. RESULTS: A total of 298 subjects (mean age: 35.7 ± 8.4 years; male: 134 [45.0%]; VC-dual: 100, VAC-triple: 98, bismuth-quadruple: 100) were enrolled, and 292 (98.0%) had UBT rechecked. ITT analysis showed that both VA-dual (eradication rate of 96.0%) and VAC-triple therapies (95.9%) were noninferior to bismuth-quadruple therapy (92.0%) (difference: 4.0%, 95% CI: -2.9% to 11.5%, p < 0.001; and 3.9%, 95% CI: -3.1% to 11.5%, p < 0.001, respectively). PP analysis also revealed noninferiority (96.7% or 96.7% vs. 97.4%, with difference: -2.9% and -2.9%, p = 0.009 and 0.010, respectively). The frequency of adverse events was 39.0%, 56.1%, and 71.0% in VA-dual, VAC-triple, and bismuth-quadruple therapies, respectively. CONCLUSIONS: VA-dual and VA-triple therapies are highly effective and noninferior to bismuth-quadruple therapy in Southern China. Given the lower adverse effects and fewer antibiotic use, VA-dual therapy is the preferred first-line treatment for HP infection. TRIAL REGISTRATION: Chinese Clinical Trial Registry (No. ChiCTR2200056375). Registered on February 4, 2022, https://www.chictr.org.cn/showproj.aspx?proj=14131.


Asunto(s)
Antibacterianos , Bismuto , Quimioterapia Combinada , Infecciones por Helicobacter , Helicobacter pylori , Pirroles , Sulfonamidas , Humanos , Infecciones por Helicobacter/tratamiento farmacológico , Sulfonamidas/uso terapéutico , Sulfonamidas/administración & dosificación , Masculino , Femenino , Persona de Mediana Edad , Adulto , Helicobacter pylori/efectos de los fármacos , Bismuto/uso terapéutico , Pirroles/uso terapéutico , Pirroles/administración & dosificación , Antibacterianos/uso terapéutico , Antibacterianos/administración & dosificación , China , Resultado del Tratamiento , Claritromicina/uso terapéutico , Amoxicilina/uso terapéutico , Amoxicilina/administración & dosificación , Metronidazol/uso terapéutico , Inhibidores de la Bomba de Protones/uso terapéutico , Adulto Joven , Esomeprazol/uso terapéutico , Esomeprazol/administración & dosificación
3.
MedComm (2020) ; 5(8): e666, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39070180

RESUMEN

Development of potent and broad-spectrum drugs against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remains one of the top priorities, especially in the cases of the emergence of mutant viruses and inability of current vaccines to prevent viral transmission. In this study, we have generated a novel membrane fusion-inhibitory lipopeptide IPB29, which is currently under clinical trials; herein, we report its design strategy and preclinical data. First, we surprisingly found that IPB29 with a rigid linker between the peptide sequence and lipid molecule had greatly improved α-helical structure and antiviral activity. Second, IPB29 potently inhibited a large panel of SARS-CoV-2 variants including the previously and currently circulating viruses, such as Omicron XBB.5.1 and EG.5.1. Third, IPB29 could also cross-neutralize the bat- and pangolin-isolated SARS-CoV-2-related CoVs (RatG13, PCoV-GD, and PCoV-GX) and other human CoVs (SARS-CoV, MERS-CoV, HCoV-NL63, and HCoV-229E). Fourth, IPB29 administrated as an inhalation solution (IPB29-IS) in Syrian hamsters exhibited high therapeutic and preventive efficacies against SARS-CoV-2 Delta or Omicron variant. Fifth, the pharmacokinetic profiles and safety pharmacology of IPB29-IS were extensively characterized, providing data to support its evaluation in humans. In conclusion, our studies have demonstrated a novel design strategy for viral fusion inhibitors and offered an ideal drug candidate against SARS-CoV-2 and other coronaviruses.

4.
BMC Gastroenterol ; 23(1): 231, 2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37420205

RESUMEN

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.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Humanos , Bismuto/efectos adversos , Neoplasias Gástricas/tratamiento farmacológico , Quimioterapia Combinada , Infecciones por Helicobacter/tratamiento farmacológico , Infecciones por Helicobacter/diagnóstico , Antibacterianos/efectos adversos , Inhibidores de la Bomba de Protones/efectos adversos , Amoxicilina/efectos adversos , Resultado del Tratamiento , Claritromicina/efectos adversos , Ensayos Clínicos Controlados Aleatorios como Asunto
5.
Adv Sci (Weinh) ; 10(25): e2301713, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37381645

RESUMEN

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.

6.
Nat Prod Res ; 36(8): 1980-1987, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33121294

RESUMEN

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.


Asunto(s)
Peróxido de Hidrógeno , Orchidaceae , Glicósidos/química , Glicósidos/farmacología , Células Hep G2 , Humanos , Peróxido de Hidrógeno/farmacología , Estructura Molecular , Orchidaceae/química
7.
J Nat Prod ; 84(3): 738-749, 2021 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-33606538

RESUMEN

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.


Asunto(s)
Orchidaceae/química , Sustancias Protectoras/farmacología , Succinatos/farmacología , Acetaminofén , Supervivencia Celular/efectos de los fármacos , China , Células Hep G2 , Humanos , Estructura Molecular , Fitoquímicos/aislamiento & purificación , Fitoquímicos/farmacología , Sustancias Protectoras/aislamiento & purificación , Succinatos/aislamiento & purificación
8.
Phytochemistry ; 182: 112609, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33326906

RESUMEN

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.


Asunto(s)
Bibencilos , Orchidaceae , Fenantrenos , Bibencilos/farmacología , Estructura Molecular , Fenantrenos/farmacología , Estereoisomerismo
9.
Materials (Basel) ; 13(23)2020 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-33261087

RESUMEN

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.

10.
Bioorg Chem ; 104: 104312, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33142424

RESUMEN

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.


Asunto(s)
Antiinflamatorios/farmacología , Clematis/química , Glicósidos/farmacología , Lignanos/farmacología , Fenoles/farmacología , Rizoma/química , Sesquiterpenos/farmacología , Animales , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Relación Dosis-Respuesta a Droga , Glicósidos/química , Glicósidos/aislamiento & purificación , Lignanos/química , Lignanos/aislamiento & purificación , Lipopolisacáridos/antagonistas & inhibidores , Lipopolisacáridos/farmacología , Ratones , Estructura Molecular , Óxido Nítrico/antagonistas & inhibidores , Óxido Nítrico/biosíntesis , Fenoles/química , Fenoles/aislamiento & purificación , Raíces de Plantas/química , Proteína Tirosina Fosfatasa no Receptora Tipo 1/antagonistas & inhibidores , Proteína Tirosina Fosfatasa no Receptora Tipo 1/metabolismo , Células RAW 264.7 , Sesquiterpenos/química , Sesquiterpenos/aislamiento & purificación , Relación Estructura-Actividad , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/biosíntesis
11.
Fitoterapia ; 138: 104313, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31421147

RESUMEN

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.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Bibencilos/farmacología , Orchidaceae/química , Fenantrenos/farmacología , Antineoplásicos Fitogénicos/aislamiento & purificación , Bibencilos/aislamiento & purificación , China , Células HCT116 , Células Hep G2 , Humanos , Células MCF-7 , Estructura Molecular , Fenantrenos/aislamiento & purificación , Fitoquímicos/aislamiento & purificación , Fitoquímicos/farmacología , Raíces de Plantas/química
12.
Org Biomol Chem ; 17(3): 567-572, 2019 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-30574990

RESUMEN

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.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Orchidaceae/química , Fenantrenos/farmacología , Tubérculos de la Planta/química , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Estructura Molecular , Fenantrenos/química , Fenantrenos/aislamiento & purificación , Estereoisomerismo , Relación Estructura-Actividad
13.
Phytochemistry ; 157: 71-81, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30384089

RESUMEN

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%.


Asunto(s)
Citoprotección/efectos de los fármacos , Hígado/citología , Hígado/efectos de los fármacos , Orchidaceae/química , Ácido Succínico/química , Ácido Succínico/farmacología , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Células Hep G2 , Humanos
14.
Int J Biol Macromol ; 122: 628-635, 2019 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-30391591

RESUMEN

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.


Asunto(s)
Orchidaceae/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Tubérculos de la Planta/química , Polisacáridos/química , Polisacáridos/farmacología , Animales , Factores Inmunológicos/química , Factores Inmunológicos/farmacología , Recuento de Leucocitos , Metilación , Ratones , Peso Molecular , Monosacáridos/análisis , Timo/inmunología
15.
16.
Sci Rep ; 8(1): 5232, 2018 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-29588460

RESUMEN

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.

17.
Zhongguo Zhong Yao Za Zhi ; 42(8): 1578-1584, 2017 Apr.
Artículo en Chino | MEDLINE | ID: mdl-29071865

RESUMEN

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.


Asunto(s)
Orchidaceae/química , Fitoquímicos/análisis , Tubérculos de la Planta/química
18.
Zhongguo Zhong Yao Za Zhi ; 40(5): 908-14, 2015 Mar.
Artículo en Chino | MEDLINE | ID: mdl-26087555

RESUMEN

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.


Asunto(s)
Medicamentos Herbarios Chinos/química , Glucósidos/química , Malatos/química , Orchidaceae/química , Medicamentos Herbarios Chinos/aislamiento & purificación , Glucósidos/aislamiento & purificación , Malatos/aislamiento & purificación , Estructura Molecular , Espectrometría de Masa por Ionización de Electrospray
19.
Zhongguo Zhong Yao Za Zhi ; 39(3): 442-7, 2014 Feb.
Artículo en Chino | MEDLINE | ID: mdl-24946545

RESUMEN

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.


Asunto(s)
Orchidaceae/química , Compuestos Orgánicos/análisis , Medicamentos Herbarios Chinos/química
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