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1.
Pulm Pharmacol Ther ; 82: 102229, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37355202

RESUMO

Hypoxic pulmonary hypertension (HPH) is a devastating disease worldwide; however, effective therapeutic drugs are lacking. This study investigated the effects and underlying mechanisms of LCZ696 treatment on hypoxia-induced pulmonary hypertension. Male Sprague-Dawley (SD) rats were kept in a hypobaric chamber with an oxygen concentration of 5% for 4 weeks. Rats were treated with either LCZ696 (18 mg/kg, 36 mg/kg, and 72 mg/kg) or sildenafil. The mean pulmonary artery pressure (mPAP), right ventricle hypertrophy index (RVHI), and lung system index were measured. Hematoxylin-eosin (HE) staining, Masson staining, and immunofluorescence staining were used for histological analysis. Enzyme linked immunosorbent assay (ELISA) kits were used to determine the concentrations of inflammatory and hypoxia-related factors. Western blotting was used to examine the expression of apoptotic and PI3K/AKT signaling pathway proteins in rat lung tissue. Hypoxia increased mPAP, RVHI, and lung system index and induced pulmonary vascular remodeling, pulmonary arteriomyosis, and pulmonary artery fibrosis. LCZ696 treatment reduced the increase in mPAP, RVHI, and the lung system index and ameliorated the induced pathological changes. Hypoxia upregulated expression of NF-kB, TNF-α, IL-6, HIF-1α, and Vascular endothelial growth factor (VEGF), decreased the ratio of Bax/Bcl-2, and activated the PI3K/AKT signaling pathway in lung tissue, and these effects were partially reversed by treatment with LCZ696. These results demonstrated that LCZ696 can ameliorate hypoxia-induced HPH by suppressing apoptosis, inhibiting the inflammatory response, and inhibiting the PI3K/AKT signaling pathway. It provides a reference for clinical rational drug use and lays a foundation for the study of HPH therapeutic drugs.


Assuntos
Hipertensão Pulmonar , Fibrose Pulmonar , Ratos , Masculino , Animais , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/prevenção & controle , Ratos Sprague-Dawley , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Hipóxia/metabolismo , Artéria Pulmonar/patologia , Transdução de Sinais , Fibrose Pulmonar/patologia
2.
Molecules ; 28(8)2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37110565

RESUMO

The characteristics of high polarity and susceptibility to oxidation in phenolic glycosides increase the difficulty of their separation from natural products. In the present study, two new phenolic glycosides with similar structures were isolated from Castanopsis chinensis Hance using a combination of multistep CC and high-speed countercurrent chromatography. Preliminary separation of the target fractions was carried out by Sephadex LH-20 chromatography (100-0% EtOH in H2O). High-speed countercurrent chromatography with an optimized solvent system of N-Hexane/Ethyl acetate/Methanol/Water (1:6:3:4, v/v/v/v) with a satisfactory stationary phase retention and separation factor was used for further separation and purification of the phenolic glycosides. Consequently, two new phenolic glycoside compounds were obtained with purities of 93.0% and 95.7%. 1D-NMR and 2D-NMR spectroscopy, mass spectrometry, and optical rotation were employed to identify their structures, which were assigned as chinensin D and chinensin E. The antioxidant and α-glucosidase inhibitory activities of these two compounds were evaluated using a DPPH antioxidant assay and a α-glucosidase inhibitory assay. Both compounds showed good antioxidant activity with IC50 values of 54.5 ± 0.82 µg/mL and 52.5 ± 0.47 µg/mL. The α-glucosidase inhibitory activity of the compounds was poor. The successful isolation and structure identification of the two new compounds provides materials not only for a systematic isolation method of phenolic glycosides with similar structures, but also for the screening of antioxidants and enzyme inhibitors.


Assuntos
Antioxidantes , Glicosídeos , Glicosídeos/farmacologia , Glicosídeos/química , Antioxidantes/farmacologia , Antioxidantes/química , alfa-Glucosidases , Extratos Vegetais/química , Espectrometria de Massas , Distribuição Contracorrente/métodos , Fenóis/farmacologia , Cromatografia Líquida de Alta Pressão/métodos
3.
Chin J Traumatol ; 26(3): 147-154, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35985904

RESUMO

PURPOSE: Child head injury under impact scenarios (e.g. falls, vehicle crashes, etc.) is an important topic in the field of injury biomechanics. The head of piglet was commonly used as the surrogate to investigate the biomechanical response and mechanisms of pediatric head injuries because of the similar cellular structures and material properties. However, up to date, piglet head models with accurate geometry and material properties, which have been validated by impact experiments, are seldom. We aim to develop such a model for future research. METHODS: In this study, first, the detailed anatomical structures of the piglet head, including the skull, suture, brain, pia mater, dura mater, cerebrospinal fluid, scalp and soft tissue, were constructed based on CT scans. Then, a structured butterfly method was adopted to mesh the complex geometries of the piglet head to generate high-quality elements and each component was assigned corresponding constitutive material models. Finally, the guided drop tower tests were conducted and the force-time histories were ectracted to validate the piglet head finite element model. RESULTS: Simulations were conducted on the developed finite element model under impact conditions and the simulation results were compared with the experimental data from the guided drop tower tests and the published literature. The average peak force and duration of the guide drop tower test were similar to that of the simulation, with an error below 10%. The inaccuracy was below 20%. The average peak force and duration reported in the literature were comparable to those of the simulation, with the exception of the duration for an impact energy of 11 J. The results showed that the model was capable to capture the response of the pig head. CONCLUSION: This study can provide an effective tool for investigating child head injury mechanisms and protection strategies under impact loading conditions.


Assuntos
Traumatismos Craniocerebrais , Crânio , Animais , Suínos , Análise de Elementos Finitos , Crânio/lesões , Traumatismos Craniocerebrais/diagnóstico por imagem , Encéfalo , Fenômenos Biomecânicos , Couro Cabeludo
4.
Molecules ; 27(5)2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35268622

RESUMO

The roots of Melastoma malabathricum subsp. normale (D. Don) Karst. Mey have been used in traditional ethnic medicine systems in China to treat inflammation-triggered ailments, such as trauma, toothache, and fever. Therefore, the aim of this study is to screen for compounds with anti-inflammatory activity in the title plant. The extract of M. malabathricum subsp. normale roots was separated using various chromatographic methods, such as silica gel, ODS C18, MCI gel, and Sephadex LH-20 column chromatography, as well as semi-preparative HPLC. One new complex tannin, named whiskey tannin D (1), and an undescribed tetracyclic depsidone derivative, named guanxidone B (2), along with nine known polyphenols (2-10) and three known depsidone derivatives (12-14) were obtained from this plant. The structures of all compounds were elucidated by extensive NMR and CD experiments in conjunction with HR-ESI-MS data. All these compounds were isolated from this plant for the first time. Moreover, compounds 1-4, 8, and 10-14 were obtained for the first time from the genus Melastoma, and compounds 1, 2, and 11-14 have not been reported from the family Melastomataceae. This is the first report of complex tannin and depsidone derivatives from M. malabathricum subsp. normale, indicating their chemotaxonomic significance to this plant. Compounds 1-12 were investigated for their anti-inflammatory activities on the production of the nitric oxide (NO) in lipopolysaccharide (LPS)-stimulated RAW264.7 cells, and compounds 1, 11, and 12 showed anti-inflammatory activities with IC50 values of 6.46 ± 0.23 µM, 8.02 ± 0.35 µM, and 9.82 ± 0.43 µM, respectively. The structure-activity relationship showed that the catechin at glucose C-1 in ellagitannin was the key to its anti-inflammatory activity, while CH3O- at C-16 of aromatic ring A in depsidone derivatives had little effect on its anti-inflammatory activity. The study of structure-activity relationships is helpful to quickly discover new anti-inflammatory drugs. The successful isolation and structure identification of these compounds, especially complex tannin 1, not only provide materials for the screening of anti-inflammatory compounds, but also provide a basis for the study of chemical taxonomy of the genus Melastoma.


Assuntos
Melastomataceae , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Depsídeos , Lactonas , Melastomataceae/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Polifenóis/farmacologia
5.
Pharmacol Res ; 163: 105187, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32916255

RESUMO

Traditional Chinese Medicine (TCM) is a medical science and cultural heritage empirically applied and reserved by Chinese people for thousands of years. With comprehensive prosperity of China and rapid elaboration of technology, healthcare status of Chinese people has become one of the most crucial concerns of the country. Nearly 30 policies and measures regarding TCM development have been issued since the 18th National Congress of the Communist Party of People's Republic of China in 2012. This review introduced a detailed evolutionary course of TCM in China with an emphasis on understanding the roadmap of TCM related policies and measures in China.


Assuntos
Política de Saúde , Medicina Tradicional Chinesa , China , História do Século XX , História do Século XXI , Medicina Tradicional Chinesa/história
6.
Molecules ; 26(2)2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33440779

RESUMO

The aim of this study was to characterize hydrolyzable tannins in Polygonaceous plants, as only a few plants have previously been reported to contain ellagitannins. From Persicaria chinensis, a new hydrolyzable tannin called persicarianin was isolated and characterized to be 3-O-galloyl-4,6-(S)-dehydrohexahydroxydiphenoyl-d-glucose. Interestingly, acid hydrolysis of this compound afforded ellagic acid, despite the absence of a hexahydroxydiphenoyl group. From the rhizome of Polygonum runcinatum var. sinense, a large amount of granatin A, along with minor ellagitannins, helioscpoinin A, davicratinic acids B and C, and a new ellagitannin called polygonanin A, were isolated. Based on 2D nuclear magnetic resonance (NMR) spectroscopic examination, the structure of polygonanin A was determined to be 1,6-(S)-hexahydroxydiphenoyl-2,4-hydroxychebuloyl-ß-d-glucopyranose. These are the second and third hydrolyzable tannins isolated from Polygonaceous plants. In addition, oligomeric proanthocyanidins of Persicaria capitatum and P. chinensis were characterized by thiol degradation. These results suggested that some Polygonaceous plants are the source of hydrolyzable tannins not only proanthocyanidins.


Assuntos
Taninos Hidrolisáveis/análise , Polygonaceae/química , Proantocianidinas/análise , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Polifenóis/análise , Rizoma/química
7.
Molecules ; 26(13)2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34206838

RESUMO

Polyphenols, widely distributed in the genus Melastoma plants, possess extensive cellular protective effects such as anti-inflammatory, anti-tyrosinase, and anti-obesity, which makes it a potential anti-inflammatory drug or enzyme inhibitor. Therefore, the aim of this study is to screen for the anti-inflammatory and enzyme inhibitory activities of compounds from title plant. Using silica gel, MCI, ODS C18, and Sephadex LH-20 column chromatography, as well as semipreparative HPLC, the extract of Melastoma normale roots was separated. Four new ellagitannins, Whiskey tannin C (1), 1-O-(4-methoxygalloyl)-6-O-galloyl-2,3-O-(S)-hexahydroxydiphenoyl-ß-d-glucose (2), 1-O-galloyl-6-O-(3-methoxygalloyl)-2,3-O-(S)-hexahydroxydiphenoyl-ß-d-glucose (3), and 1-O-galloyl-6-O-vanilloyl-2,3-O-(S)-hexahydroxydiphenoyl-ß-d-glucose (4), along with eight known polyphenols were firstly obtained from this plant. The structures of all isolates were elucidated by HRMS, NMR, and CD analyses. Using lipopolysaccharide (LPS)-stimulated RAW2 64.7 cells, we investigated the anti-inflammatory activities of compounds 1-4, unfortunately, none of them exhibit inhibit nitric oxide (NO) production, their IC50 values are all > 50 µM. Anti-tyrosinase activity assays was done by tyrosinase inhibition activity screening model. Compound 1 showed weak tyrosinase inhibitory activity with IC50 values of 426.02 ± 11.31 µM. Compounds 2-4 displayed moderate tyrosinase inhibitory activities with IC50 values in the range of 124.74 ± 3.12-241.41 ± 6.23 µM. The structure-activity relationships indicate that hydroxylation at C-3', C-4', and C-3 in the flavones were key to their anti-tyrosinase activities. The successful isolation and structure identification of ellagitannin provide materials for the screening of anti-inflammatory drugs and enzyme inhibitors, and also contribute to the development and utilization of M. normale.


Assuntos
Anti-Inflamatórios/análise , Inibidores Enzimáticos/farmacologia , Taninos Hidrolisáveis/análise , Melastomataceae/química , Monofenol Mono-Oxigenase/antagonistas & inibidores , Extratos Vegetais/química , Polifenóis/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Concentração Inibidora 50 , Camundongos , Estrutura Molecular , Óxido Nítrico/metabolismo , Extratos Vegetais/análise , Polifenóis/química , Células RAW 264.7
8.
Molecules ; 22(1)2017 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-28106844

RESUMO

In the course of a phytochemical and chemotaxonomical investigation of Castanopsis species (Fagaceae), three new phenolic compounds, (3R,1'S)-[1'-(6″-O-galloyl-ß-d-gluco-pyranosyl)oxyethyl]-3-hydroxy-dihydrofuran-2(3H)-one (1), (2R,3S)-2-[2'-(galloyl)oxyethyl]-dihydroxybutanoic acid (2), and (3S,4S)-3-hydroxymethyl-3,4-dihydro-5,6,7-trihydroxy-4-(4'-hydroxy-3'-methoxyphenyl)-1H-[2]-benzopyran-1-one (3) were isolated from the fresh leaves of Castanopsis fargesii. In addition, a known phenolic glycoside, gentisic acid 5-O-α-l-rhamnopyranosyl-(1→2)-ß-d-glucopyranoside (4) was also isolated and identified. Their structures were elucidated by means of spectroscopic methods including one- and two-dimensional NMR techniques.


Assuntos
Fagaceae/química , Fenóis/química , Folhas de Planta/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Extratos Vegetais/química
9.
Zhong Yao Cai ; 39(6): 1291-5, 2016 Jun.
Artigo em Zh | MEDLINE | ID: mdl-30156800

RESUMO

Objective: To study the chemical constituents of Litchi chinensis pericarp. Methods: The compounds were isolated by Sephadex LH-20, MCI gel CHP 20 P, Toyopearl Butly-650 C, Toyopearl WH-40 F column chromatographies and semi-preparative HPLC, the structures were elucidated by NMR and mass spectroscopic MS data analysis. Results: 14 compounds were obtained and their structures were identified as quercetin( 1), chrysoeriol( 2),kaemperol-3-O-ß-D-glucoside( 3), manghaslin( 4), isorhamnetin-3-O-robinobioside( 5), ( +)-gallocatechin( 6), (-) epicatechin-3-O-gallate( 7), cinnamtannin B-1( 8), isolariciresinol-9-O-ß-D-xyloside( 9), ( +)-5-methoxyisolariciresinol-9-O-ß-D-xylopyranoside( 10), vanillic acid( 11), 3, 4, 3', 4'-tetrahydroxy biphenyl( 12), tachioside( 13) and isotachioside( 14). Conclusion: Compounds 1 ~ 7,9 ~ 14 are obtained from this plant pericarp for the first time.


Assuntos
Litchi , Catequina/análogos & derivados , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas , Glucosídeos , Glicosídeos , Espectrometria de Massas , Proantocianidinas , Quercetina/análogos & derivados
10.
Bioorg Med Chem ; 23(15): 4248-4255, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26162497

RESUMO

A novel series of etravirine-VRX-480773 hybrids were designed using structure-guided molecular hybridization strategy and fusing the pharmacophore templates of etravirine and VRX-480773. The anti-HIV-1 activity and cytotoxicity was evaluated in MT-4 cell cultures. The most active hybrid compound in this series, N-(2-chlorophenyl)-2-((4-(4-cyano-2,6-dimethylphenoxy)pyrimidin-2-yl)thio)acetamide 3d (EC50=0.24 , SI>1225), was more potent than delavirdine (EC50=0.66 µM, SI>67) in the anti-HIV-1 in vitro cellular assay. Studies of structure-activity relationships established a correlation between anti-HIV activity and the substitution pattern of the acetanilide group.


Assuntos
Fármacos Anti-HIV/química , Fármacos Anti-HIV/farmacologia , Inibidores da Transcriptase Reversa/química , Acetanilidas/química , Fármacos Anti-HIV/síntese química , Linhagem Celular , Técnicas de Química Sintética , Descoberta de Drogas , Avaliação Pré-Clínica de Medicamentos/métodos , Transcriptase Reversa do HIV/antagonistas & inibidores , HIV-1/efeitos dos fármacos , Humanos , Simulação de Dinâmica Molecular , Nitrilas , Piridazinas/química , Pirimidinas , Inibidores da Transcriptase Reversa/síntese química , Inibidores da Transcriptase Reversa/farmacologia , Relação Estrutura-Atividade , Triazóis/química
11.
Biomed Chromatogr ; 29(9): 1453-60, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25753317

RESUMO

A simple, specific and sensitive LC-MS/MS method was developed and validated for the simultaneous determination of metoprolol (MET), α-hydroxymetoprolol (HMT) and O-desmethylmetoprolol (DMT) in rat plasma. The plasma samples were prepared by protein precipitation, then the separation of the analytes was performed on an Agilent HC-C18 column (4.6 × 250 mm, 5 µm) at a flow rate of 1.0 mL/min, and post-column splitting (1:4) was used to give optimal interface flow rates (0.2 mL/min) for MS detection; the total run time was 8.5 min. Mass spectrometric detection was achieved using a triple-quadrupole mass spectrometer equipped with an electrospray source interface in positive ionization mode. The method was fully validated in terms of selectivity, linearity, accuracy, precision, stability, matrix effect and recovery over a concentration range of 3.42-7000 ng/mL for MET, 2.05-4200 ng/mL for HMT and 1.95-4000 ng/mL for DMT. The analytical method was successfully applied to herb-drug interaction study of MET and breviscapine after administration of breviscapine (12.5 mg/kg) and MET (40 mg/kg). The results suggested that breviscapine have negligible effect on pharmacokinetics of MET in rats; the information may be beneficial for the application of breviscapine in combination with MET in clinical therapy.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/análise , Flavonoides/sangue , Metoprolol/sangue , Espectrometria de Massas em Tandem/métodos , Animais , Medicamentos de Ervas Chinesas/farmacocinética , Flavonoides/farmacocinética , Interações Ervas-Drogas , Masculino , Metoprolol/análogos & derivados , Metoprolol/farmacocinética , Ratos , Ratos Wistar
12.
J Org Chem ; 79(12): 5432-47, 2014 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-24824117

RESUMO

Nineteen new highly oxygenated norbisabolane sesquiterpenoids, phyllanthacidoid acid methyl ester (1), and C-T (4-21), were isolated from Phyllanthus acidus Skeels, together with two known ones, phyllanthusols A (2) and B (3), whose sugar moiety was revised as glucosamine-N-acetate, rather than the previously assigned mannosamine-N-acetate. Compounds 2 and 3 were renamed respectively as phyllanthacidoids A (2) and B (3) to avoid confusion. All of the isolates except for 1 are glycosides, whose saccharide moieties possess a pentaoxy cyclohexane (scyllo quercitol) connecting with glucosamine-N-acetate or glucosyl moieties, which are first examples in natural products. Phyllanthacidoids N-R (15-19) with 8R configurations and/or 5,8-diketal skeleton, are unprecedented structures among norbisabolane sesquiterpenoids. Phyllanthacidoids S (20) and T (21) have the unusual tricyclo [3.1.1.1] oxygen bridge skeleton formed by a diketal system, of which the relative configurations of the aliphatic chain were assigned on the basis of heteronuclear coupling constants. The absolute configurations of compounds (1-21) were established by means of calculated electronic circular dichroism (ECD) and coupling constants. Compounds 1-5, 7-9, 10, and 14 displayed potential anti-hepatitis B virus (HBV) activities, with IC50 values of 0.8-36 µM against HBV surface antigen (HBsAg) and HBV excreted antigen (HBeAg), and the results indicated that the 5-ketal group and sugar moieties had contributions to the selectivity of HBsAg and HBeAg.


Assuntos
Antivirais/química , Antivirais/isolamento & purificação , Antivirais/farmacologia , Benzofuranos/química , Benzofuranos/farmacologia , Dissacarídeos/química , Dissacarídeos/farmacologia , Glicosídeos/química , Antígenos de Superfície da Hepatite B/química , Antígenos E da Hepatite B/química , Vírus da Hepatite B/química , Vírus da Hepatite B/efeitos dos fármacos , Phyllanthus/química , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Compostos de Espiro/química , Compostos de Espiro/farmacologia , Benzofuranos/isolamento & purificação , Dissacarídeos/isolamento & purificação , Antígenos de Superfície da Hepatite B/imunologia , Antígenos E da Hepatite B/imunologia , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Teoria Quântica , Compostos de Espiro/isolamento & purificação , Estereoisomerismo
13.
Org Biomol Chem ; 12(43): 8764-74, 2014 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-25268491

RESUMO

During the process exploring anti-viral compounds from Phyllanthus species, eight new highly oxygenated bisabolane sesquiterpenoid glycoside phyllaemblicins G1­G8 (1­8) were isolated from Phyllanthus emblica, along with three known compounds, phyllaemblicin F (9), phyllaemblic acid (10) and glochicoccin D (11). Phyllaemblicin G2 (2), bearing a tricyclo [3.1.1.1] oxygen bridge ring system, is an unusual sesquiterpenoid glycoside, while phyllaemblicins G6­G8 (6­8) are dimeric sesquiterpenoid glycosides with two norbisabolane units connecting through a disaccharide. All the structures were elucidated by the extensive analysis of HRMS and NMR data. The relative configuration of phyllaemblicin G2 was constructed based on heteronuclear coupling constants measurement, and the absolute configurations for all new compounds were established by calculated electronic circular dichroism (ECD) using time dependent density functional theory. The sesquiterpenoid glycoside dimers 6­9 displayed potential anti-hepatitis B virus (HBV) activities, especially for the new compound 6 with IC50 of 8.53 ± 0.97 and 5.68 ± 1.75 µM towards the HBV surface antigen (HBsAg) and HBV excreted antigen (HBeAg) secretion, respectively.


Assuntos
Antivirais/química , Glicosídeos/química , Vírus da Hepatite B/efeitos dos fármacos , Phyllanthus emblica/química , Sesquiterpenos/química , Antivirais/isolamento & purificação , Antivirais/farmacologia , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Células Hep G2 , Antígenos de Superfície da Hepatite B/análise , Antígenos E da Hepatite B/análise , Vírus da Hepatite B/fisiologia , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Extratos Vegetais/química , Raízes de Plantas/química , Teoria Quântica , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Terpenos/química , Terpenos/isolamento & purificação , Terpenos/farmacologia
14.
Environ Monit Assess ; 186(11): 8037-48, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25112841

RESUMO

Long-distance pipeline construction results in marked human disturbance of the regional ecosystem and brings into question the safety of pipeline construction with respect to the environment. Thus, the direct environmental impact and proper handling of such large projects have received much attention. The potential environmental effects, however, have not been fully addressed, particularly for large linear pipeline projects, and the threshold of such effects is unclear. In this study, two typical eco-fragile areas in western China, where large linear construction projects have been conducted, were chosen as the case study areas. Soil quality indices (SQI) and vegetation indices (VI), representing the most important potential effects, were used to analyze the scope of the effect of large pipeline construction on the surrounding environment. These two indices in different buffer zones along the pipeline were compared against the background values. The analysis resulted in three main findings. First, pipeline construction continues to influence the nearby eco-environment even after a 4-year recovery period. During this period, the effect on vegetation due to pipeline construction reaches 300 m beyond the working area, and is much larger in distance than the effect on soil, which is mainly confined to within 30 m either side of the pipeline, indicating that vegetation is more sensitive than soil to this type of human disturbance. However, the effect may not reach beyond 500 m from the pipeline. Second, the scope of the effect in terms of distance on vegetation may also be determined by the frequency of disturbance and the intensity of the pipeline construction. The greater the number of pipelines in an area, the higher the construction intensity and the more frequent the disturbance. Frequent disturbance may expand the effect on vegetation on both sides of the pipeline, but not on soil quality. Third, the construction may eliminate the stable, resident plant community. During the recovery period, the plant community in the work area of the pipeline is replaced by some species that are rare or uncommon in the resident plant community because of human disturbance, thereby increasing the plant diversity in the work area. In terms of plant succession, the duration of the recovery period has a direct effect on the composition and structure of the plant community. The findings provide a theoretical basis and scientific foundation for improving the environmental impact assessment (EIA) of oil and gas pipeline construction as it pertains to the desert steppe ecosystem, and provide a reference point for recovery and management of the eco-environment during the pipeline construction period.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Monitoramento Ambiental , Campos de Petróleo e Gás , China , Clima , Ecologia , Meio Ambiente , Humanos , Plantas , Medição de Risco , Solo/química
15.
Environ Monit Assess ; 186(3): 1825-35, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24141486

RESUMO

Disturbance to the physical-chemical properties of soil caused by pipeline installation was evaluated using two soil quality indices to identify the scale of disturbance and the restoration cycle. The integrated soil quality index (SQI) was used to evaluate soil property changes in different pipeline zones (0, 10, 20, and 50 m from the pipeline) at sites 1 and 2. The soil restoration index (SRI) was used to estimate soil recovery from three pipelines with different recovery periods (2, 6, and 8 years) at site 3. The results showed that the adverse effects of pipeline construction on soil properties mainly occurred in the right-of-way (ROW) areas and the impaired zones were in the order trench > piling and working areas > 20 and 50 m. The soil restoration cycle may be complete within 6 years of construction. At site 3, the SRI in the ROW area of a pipeline after 6 years of restoration was close to 100 %, showing full soil recovery. However, the SRI in the disturbed areas of a pipeline after 2 years of restoration was much lower than that after 6 years of restoration, indicating that the soil was still recovering from the disturbance. The topography may change the intensity of disturbance in different areas due to the movement patterns of heavy machinery and traffic routes. There were local variations in the SQI within the pipeline zones, with flat areas suffering greater disturbance than hilly areas, indicating that topography should be considered in a pipeline's environmental impact assessment.


Assuntos
Monitoramento Ambiental , Campos de Petróleo e Gás , Poluentes do Solo/análise , Solo/química , Conservação dos Recursos Naturais , Indústria da Construção , Ecossistema , Recuperação e Remediação Ambiental , Indústrias Extrativas e de Processamento
16.
Tumour Biol ; 34(3): 1685-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23430585

RESUMO

The aim of this study was to investigate the association between keratin 17 (K17) expression and the clinicopathological features of patients with epithelial ovarian cancer (EOC). K17 expression was detected by real-time quantitative RT-PCR in EOC and adjacent noncancerous tissues. In addition, K17 expression was analyzed by immunohistochemistry in 104 clinicopathologically characterized EOC cases. The expression levels of K17 mRNA and protein in EOC tissues were both significantly higher than those in noncancerous tissues. In addition, positive expression of K17 correlated with the clinical stage (p=0.001). Furthermore, Kaplan-Meier survival analysis showed that a high expression level of K17 resulted in a significantly poor prognosis of EOC patients. Multivariate analysis revealed that EOC expression level was an independent prognostic parameter for the overall survival rate of EOC patients. Our data are the first to suggest that increased K17 expression in EOC is significantly associated with aggressive progression and poor prognosis. K17 may be an important molecular marker for predicting the carcinogenesis, progression, and prognosis of EOC.


Assuntos
Biomarcadores Tumorais/genética , Cistadenocarcinoma Seroso/genética , Perfilação da Expressão Gênica , Queratina-17/genética , Neoplasias Ovarianas/genética , Ovário/metabolismo , Biomarcadores Tumorais/metabolismo , Estudos de Casos e Controles , Cistadenocarcinoma Seroso/metabolismo , Cistadenocarcinoma Seroso/mortalidade , Feminino , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Queratina-17/metabolismo , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Análise de Sequência com Séries de Oligonucleotídeos , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/mortalidade , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida
17.
J Basic Microbiol ; 53(7): 622-9, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22961592

RESUMO

In our previous study, the sequence of a matrix attachment region binding protein (MBP) cDNA was cloned from the unicellular green alga Dunaliella salina. However, the nucleotide sequence of this gene has not been reported so far. In this paper, the nucleotide sequence of MBP was cloned and characterized, and its gene copy number was determined. The MBP nucleotide sequence is 5641 bp long, and interrupted by 12 introns ranging from 132 to 562 bp. All the introns in the D. salina MBP gene have orthodox splice sites, exhibiting GT at the 5' end and AG at the 3' end. Southern blot analysis showed that MBP only has one copy in the D. salina genome.


Assuntos
Clorófitas/metabolismo , Proteínas Fúngicas/genética , Proteínas de Ligação à Região de Interação com a Matriz/genética , Sequência de Bases , Southern Blotting , Clonagem Molecular , DNA de Algas/química , DNA de Algas/metabolismo , DNA Complementar/química , DNA Complementar/metabolismo , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Genoma de Planta , Genômica , Íntrons , Proteínas de Ligação à Região de Interação com a Matriz/química , Proteínas de Ligação à Região de Interação com a Matriz/metabolismo , Regiões de Interação com a Matriz , Dados de Sequência Molecular
18.
Mitochondrial DNA B Resour ; 8(2): 236-239, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36816059

RESUMO

Castanopsis fordii Hance 1884 is a typical evergreen broad-leaved forest plant in the south subtropical and middle subtropical regions of China. It has high utilization value in wood production and soil erosion protection. Here, we first reported and characterized the complete chloroplast (cp) genome sequence of C. fordii based on Illumina paired-end sequencing data. The complete cp genome sequence of C. fordii was 160,853 base pairs (bp) in length which contained two inverted repeats (IRs) of 25,699 bp separated by a large single-copy (LSC) and a small single copy (SSC) of 90,474 bp and 18,981 bp, respectively. The cpDNA contained 129 genes, comprising 85 protein-coding genes, 36 tRNA genes, 8 rRNA genes. The overall GC content of the plastome was 36.8%. Phylogenetic analysis base on 14 chloroplast genomes indicated that C. fordii was closely related to the species C. tibetana and C. concinna in Fagaceae.

19.
Nat Prod Res ; 37(14): 2383-2389, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35300550

RESUMO

Two new isoflavone compounds, Dalhancei A (1) and Dalhancei B (2), along with a known compound epicatechin (3) were isolated from 80% methanol extract of the barks of Dalbergia hancei Benth. The structures of compounds 1-3 were elucidated by comparison with the literature and physical data analysis, including optical rotation, MS, 1D and 2D NMR spectra. Compounds 1 and 2 showed weak inhibitory activity against tyrosinase at 16.22 mmol/L, with inhibition rates of 42.23 ± 0.18% and 45.68 ± 0.17%, respectively; compound 1 exhibited weak inhibitory activity against α-glucosidase with the inhibition rate of 43.72 ± 0.22% at 5.41 mmol/L, compounds 2 and 3 had better α-glucosidase inhibitory activity than compound 1 with IC50 values of 0.90 ± 0.18 and 0.41 ± 0.17 mmol/L, respectively.


Assuntos
Dalbergia , Isoflavonas , Dalbergia/química , Estrutura Molecular , Isoflavonas/farmacologia , Isoflavonas/química , alfa-Glucosidases , Extratos Vegetais/farmacologia , Extratos Vegetais/química
20.
Nat Prod Res ; 37(21): 3605-3609, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35787070

RESUMO

Phytochemical investigation of the Leaves of Castanopsis eyrei led to the isolation of two new natural truxinate derivatives and a new phenyldilactone. The structures of the new natural compounds were determined by spectroscopic methods and chemical evidence as 3,3',4,4'-tetrahydroxy-ß-truxillic acid (1), 3,3',4,4'-tetrahydroxy-δ-truxillic acid (2), 3'-hydroxymaysedilactone A (3). Establishment of a Caenorhabditis elegans lipid metabolism model using GFP and mCherry fluorescently labeled lipid droplets to screen compound 3 for its activity in reducing lipid accumulation.

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