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3.
Sci Rep ; 9(1): 6991, 2019 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-31061445

RESUMO

Angelica sinensis (Oliv.) Diels is a widely-used traditional Chinese herbal medicine in treating osteoporosis. Ligustilide (LIG) is the main component of A. sinensis and is considered to be the most effective biologically active ingredient in this plant. LIG has been found to have multiple pharmacological activities, such as anti-atherosclerosis, neuroprotection, anticancer, anti-inflammatory and analgesic. However, little is known regarding its anti-osteoporotic effects. The aims of this study were to investigate any protective effect of LIG on bone formation. The results showed that LIG significantly ameliorated inhibition of bone formation in zebrafish caused by prednisolone. LIG promoted osteoblast differentiation, including that of the pre-osteoblastic cell line MC3T3-E1 and bone marrow mesenchymal stem cells. LIG greatly improved the viability of MC3T3-E1 cells exposed to H2O2, attenuated H2O2-induced apoptosis and increased the expression of Bcl-2. Furthermore, LIG treatment lead to marked activation of phosphorylated EGFR and ERK1/2. These effects could be obviously inhibited by blocking GPR30 signaling with the specific inhibitor G15. Collectively, the results reveal that GPR30 is a positive switch for LIG to increase bone formation via regulation of EGFR, and these results provide evidence for the potential of LIG to treat osteoporosis.


Assuntos
4-Butirolactona/análogos & derivados , Conservadores da Densidade Óssea/farmacologia , Proteínas de Fluorescência Verde/genética , Osteoblastos/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Receptores Acoplados a Proteínas G/genética , Proteínas de Peixe-Zebra/genética , 4-Butirolactona/farmacologia , Angelica sinensis/química , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Linhagem Celular , Modelos Animais de Doenças , Embrião não Mamífero , Regulação da Expressão Gênica , Proteínas de Fluorescência Verde/metabolismo , Larva , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Osteoblastos/citologia , Osteoblastos/metabolismo , Osteoporose/genética , Osteoporose/metabolismo , Osteoporose/patologia , Prednisolona/antagonistas & inibidores , Prednisolona/farmacologia , Cultura Primária de Células , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Receptores Acoplados a Proteínas G/metabolismo , Peixe-Zebra , Proteínas de Peixe-Zebra/metabolismo
4.
Health Phys ; 106(4): 459-65, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24562066

RESUMO

Current methods of evaluating radiation-induced cancer risk depend on the organ dose but not explicitly on extensive quantities such as the organ mass. However, at the same organ dose, one may expect the larger number of cells in a larger organ to lead to a higher cancer risk. Here the author introduces organ- and radiation type-specific cell cancer risk coefficients and obtains analytical relations between cancer risk and the radiation environment, which contains the dependence of cancer risk on organ masses. The excess cancer risk induced by low dose radiation for an organ is shown to be directly proportional to the organ mass. Therefore the total excess risk for all solid cancers depends directly on organ masses and consequently on body weight or size. This method is also being compared with three existing methods of evaluating the radiation-induced cancer risk, and special cases where this formulation matches each method are demonstrated. The results suggest that the direct dependence of cancer risk on organ masses needs to be checked against existing epidemiological data and, if verified, should be included in the methodology for the evaluation of radiation-induced cancer risk, in particular the individual risk. This dependence is also expected to affect the cancer risk transport from one population group to another that is different in organ mass, body weight or height.


Assuntos
Neoplasias Induzidas por Radiação/epidemiologia , Doses de Radiação , Tamanho Corporal , Peso Corporal , Relação Dose-Resposta à Radiação , Feminino , Humanos , Masculino , Modelos Teóricos , Neoplasias Induzidas por Radiação/etiologia , Tamanho do Órgão , Medição de Risco
5.
Dis Esophagus ; 27(3): 294-302, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23822165

RESUMO

CXCR4 belongs to a family of G protein-coupled cell surface receptors and has been proved to a prognostic marker in a various tumors, including esophageal squamous cell cancer. In this study, we analyzed CXCR4 expression in tumor tissue and metastatic tumor tissues of lymph node by immunohistochemistry. CXCR4 was found to be an independent factor of patients' survival and heterogeneously expressed in tumor tissues. Compared with the primary tumor tissues, the scores of CXCR4 expression were significantly higher in corresponding metastatic tumor tissues of lymph nodes (P < 0.01). It was suggested CXCR4-positive cells were prone to migrate to lymph nodes. In the further experiments in vitro, we confirmed heterogeneous expression of CXCR4 in esophageal squamous cell cancer cell lines (KYSE70, Ec109, and CaES17) by flow cytometry analysis. Meanwhile, two subpopulations were isolated from Ec109 based on CXCR4 membrane expression by fluorescence-activated cell sorting. CXCR4-positive cells showed stronger migration ability in Boyden chamber assay than CXCR4 negative ones (P < 0.01). However, no significant difference of cell proliferation was found between the two subpopulations in colony formation assay (P > 0.05). We concluded that CXCR4 might be a key molecule in esophageal squamous cell cancer metastasis.


Assuntos
Carcinoma de Células Escamosas/química , Carcinoma de Células Escamosas/secundário , Neoplasias Esofágicas/química , Neoplasias Esofágicas/patologia , Expressão Gênica , Linfonodos/química , Receptores CXCR4/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Intervalo Livre de Doença , Neoplasias Esofágicas/genética , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Receptores CXCR4/genética , Taxa de Sobrevida
6.
Phys Rev Lett ; 106(21): 217001, 2011 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-21699329

RESUMO

We report on the interplane c-axis electronic response of FeTe(0.55)Se(0.45) investigated by infrared spectroscopy. We find that the normal-state c-axis electronic response of FeTe(0.55)Se(0.45) is incoherent and bears significant similarities to those of mildly underdoped cuprates. The c-axis optical conductivity σ(c)(ω) of FeTe(0.55)Se(0.45) does not display well-defined Drude response at all temperatures. As temperature decreases, σ(c)(ω) is continuously suppressed. The incoherent c-axis response is found to be related to the strong dissipation in the ab-plane transport: a pattern that holds true for various correlated materials as well as FeTe(0.55)Se(0.45).

7.
Radiat Res ; 173(2): 238-44, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20095856

RESUMO

We calculated how the radiation environment in a habitat on the surface of the Moon would have depended on the thickness of the habitat in the 1977 galactic cosmic-ray environment. The Geant4 Monte Carlo transport code was used, and a hemispherical dome made of lunar regolith was used to simulate the lunar habitat. We investigated the effective dose from primary and secondary particles including nuclei from protons up to nickel, neutrons, charged pions, photons, electrons and positrons. The total effective dose showed a strong decrease with the thickness of the habitat dome. However, the effective dose values from secondary neutrons, charged pions, photons, electrons and positrons all showed a strong increase followed by a gradual decrease with the habitat thickness. The fraction of the summed effective dose from these secondary particles in the total effective dose increased with the habitat thickness, from approximately 5% for the no-habitat case to about 47% for the habitat with an areal thickness of 100 g/cm(2).


Assuntos
Radiação Cósmica , Lua , Método de Monte Carlo
8.
Radiat Res ; 167(3): 330-7, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17316078

RESUMO

The radiation hazard for astronauts from galactic cosmic rays (GCR) is a major obstacle to long-duration human space exploration. Space radiation transport codes have been developed to calculate the radiation environment on missions to the Moon, Mars, and beyond. We have studied how uncertainties in fragmentation cross sections at different energies affect the accuracy of predictions from such radiation transport calculations. We find that, in deep space, cross sections at energies between 0.3 and 0.85 GeV/nucleon have the largest effect in solar maximum GCR environments. At the International Space Station, cross sections at higher energies have the largest effect due to the geomagnetic cutoff.


Assuntos
Radiação Cósmica , Astronautas , Humanos , Sensibilidade e Especificidade , Voo Espacial , Astronave
9.
Adv Space Res ; 35(2): 236-42, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15934200

RESUMO

We investigated the spatial distribution of the induction of the phosphorylated form of the histone protein H2AX (gamma-H2AX), known to be activated by DSBs. Following irradiation of human fibroblast cells with 600 MeV/nucleon silicon and 600 MeV/nucleon iron ions we observed the formation of gamma-H2AX aggregates in the shape of streaks stretching over several micrometers in an x/y plane. Polyethylene shielding was used to achieve a Bragg curve distribution with beam geometry parallel to the monolayer of cells. We present data that highlights the formation of immunofluorescent gamma-H2AX tracks showing the ion trajectories across the Bragg peak of irradiated human fibroblast cells. Qualitative analyses of these distributions indicated potentially increased clustering of DNA damage before the Bragg peak, enhanced gamma-H2AX distribution at the peak, and provided visual evidence of high-linear energy transfer particle traversal of cells beyond the Bragg peak in agreement with one-dimensional transport approximations. Spatial assessment of gamma-H2AX fluorescence may provide direct insights into DNA damage across the Bragg curve for high charge and energy ions including the biological consequences of shielding and possible contributors to bystander effects.


Assuntos
Dano ao DNA , Íons Pesados , Histonas/efeitos da radiação , Transferência Linear de Energia , Fosfoproteínas/efeitos da radiação , Efeito Espectador , Radiação Cósmica , Fibroblastos/efeitos da radiação , Imunofluorescência , Humanos , Ferro , Fosforilação , Polietileno , Doses de Radiação , Proteção Radiológica , Silício
10.
Fitoterapia ; 72(7): 832-3, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11677026

RESUMO

The isolation from the acetone extract of Lethariella cladonioides of the new compound cladonioidesin (1) and 10 other constituents is reported.


Assuntos
Ascomicetos , Ácidos Ftálicos/química , Fitoterapia , Extratos Vegetais/química , Humanos
11.
Phytochemistry ; 58(1): 179-83, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11524129

RESUMO

Four 7,20-epoxy ent-kaurane diterpenoids, xerophilusins G (1) and I-K (2-4), were isolated from the leaves of Isodon xerophilus, along with four known ones, enanderianin C (5), rosthorin A (6), longikaurin B (7), and rabdoternin D (8). Their structures were determined primarily using NMR spectroscopic techniques. The structure and stereochemistry of 3 were confirmed by X-ray crystallography. Compounds 4 and 7 exhibited broad cytotoxicity against four kinds of human tumor cells (K562, HL-60, HCT, and MKN-28 cells) in the range of 2.23-15.35 and 0.30-8.61 microg/ml, respectively.


Assuntos
Antineoplásicos Fitogênicos/química , Diterpenos do Tipo Caurano , Diterpenos/química , Lamiaceae/química , Plantas Tóxicas/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/toxicidade , Cristalografia por Raios X , Diterpenos/isolamento & purificação , Diterpenos/toxicidade , Ensaios de Seleção de Medicamentos Antitumorais , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Modelos Moleculares , Conformação Molecular
12.
Phytochemistry ; 56(8): 801-6, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11324907

RESUMO

Seven ergostane-type sterols and two mono-glucosides were isolated from the ethyl acetate soluble fraction of Lactarium rolemus. Three are previously unknown, i.e. 3-O-beta-D-glucopyranosyl-22E,24R-5alpha,8alpha-epidioxyergosta-6,22-diene, 3-O-beta-D-glucopyranosyl-22E,24R-5beta,8beta-epidioxyergosta-6,22-diene and 22E,24R-ergosta-7,22-diene-3beta,5alpha,6beta,9alpha-tetraol. The structural elucidation of these compounds was mainly achieved by spectroscopic methods.


Assuntos
Agaricales/química , Fitosteróis/isolamento & purificação , Espectroscopia de Ressonância Magnética , Conformação Molecular , Fitosteróis/química
13.
J Asian Nat Prod Res ; 3(4): 299-311, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11783584

RESUMO

A new indole alkaloid, crenulatine (1), along with twenty known compounds, was isolated from the stems of Limonia Crenulata. Their structures were identified by spectral means. Those compounds include four alkaloids, four coumarins, two flavanones, three tetranortriterpenoids, one triterpenoid, three steroids, two lignans and two aromatic compounds.


Assuntos
Alcaloides/isolamento & purificação , Indóis/isolamento & purificação , Rutaceae/química , Alcaloides/química , Cromatografia em Gel , Cromatografia Gasosa-Espectrometria de Massas , Indóis/química , Modelos Moleculares , Ressonância Magnética Nuclear Biomolecular , Rotação Ocular , Caules de Planta/química , Espectrofotometria Ultravioleta
14.
Planta Med ; 66(7): 624-6, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11105566

RESUMO

Two new gallotannins, pistafolins A (1) and B (2), were isolated from the leaf extract of Pistacia weinmannifolia. Their structures were determined by spectral methods. Four known gallotannins (3-6), seven known flavonoid glycosides (7-13), along with 1-O-beta-D-(6'-O-galloyl)-glucopyranosyl-3-methoxy-5-hydroxybenzen e (14), gallic acid (15), methyl gallate (16), (+)-catechin (17), and (+)-gallocatechin (18), were also isolated. Some of these compounds were tested for their cytotoxicity toward K562 cells, and two small molecular phenolic compounds, 15 and 18, showed significant inhibitory effects with IC50 values less than 5 micrograms/ml.


Assuntos
Flavonoides , Taninos Hidrolisáveis/isolamento & purificação , Fenóis/isolamento & purificação , Polímeros/isolamento & purificação , Rosales/química , Sobrevivência Celular/efeitos dos fármacos , Humanos , Taninos Hidrolisáveis/química , Taninos Hidrolisáveis/farmacologia , Células K562 , Fenóis/química , Fenóis/farmacologia , Polímeros/química , Polímeros/farmacologia , Polifenóis
15.
Fitoterapia ; 71(6): 623-6, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11077166

RESUMO

Nine phenolic compounds, including a new one, were isolated from 70% acetone extract of Craspedolobium schochii. The new compound was identified as 3-(3,4-dimethoxy-2-hydroxyphenyl)-7-hydroxy-coumarin (1) on the basis of spectroscopic evidence.


Assuntos
Cumarínicos/química , Medicamentos de Ervas Chinesas/química , Fenóis/química , Plantas Medicinais/química , Humanos
16.
Fitoterapia ; 71(6): 641-8, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11077170

RESUMO

Five new steroids, colebrin A-E (1-5) were isolated from the aerial parts of Clerodendrum colebrookianum. The structures of the new compounds were elucidated on the basis of spectral evidence.


Assuntos
Medicamentos de Ervas Chinesas/química , Plantas Medicinais/química , Saponinas/química , Humanos
17.
Fitoterapia ; 71(4): 417-9, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10925014

RESUMO

A new ent-kaurane diterpenoid, phyllostachysin C (1), together with five known compounds, sculponeatins B and C, nodosin, ursolic acid and 2 alpha-hydroxyursolic acid, were isolated from the leaves of Isodon phyllostachys. The structure of 1 was elucidated on the basis of its spectral properties.


Assuntos
Diterpenos/química , Lamiaceae , Plantas Medicinais , Medicamentos de Ervas Chinesas/química , Humanos , Folhas de Planta
18.
J Nat Prod ; 63(5): 599-601, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10843567

RESUMO

Three new 7,20:14,20-diepoxy-ent-kaurane diterpenoids, xerophilusins A-C (1-3), together with a known one, macrocalin B (4), were isolated from the leaves of Isodon xerophilus. Their structures were elucidated on the basis of their spectral properties and X-ray crystallographic analysis. Compounds 1, 2, and 4 showed significant cytotoxic activity against K562, HL-60, and MKN-28 cells.


Assuntos
Diterpenos/isolamento & purificação , Plantas Medicinais/química , Antineoplásicos Fitogênicos/farmacologia , Cristalografia por Raios X , Diterpenos/química , Diterpenos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Mitoxantrona/farmacologia , Folhas de Planta/química , Células Tumorais Cultivadas
19.
J Asian Nat Prod Res ; 2(3): 177-85, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11256691

RESUMO

Colebroside A (1), a new diglucoside of fatty acid ester of glycerin, was isolated from the aerial parts of Clerodendrum colebrookianum Walp., along with nine known compounds (2-10). Their structures were elucidated by spectroscopic and chemical methods. Compounds 2, 3, 4, 5, 7, 8, 9 and 10 have been obtained from this plant for the first time.


Assuntos
Medicamentos de Ervas Chinesas , Glucosídeos/isolamento & purificação , Lamiaceae/química , China , Glucosídeos/química , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Estruturas Vegetais/química
20.
J Asian Nat Prod Res ; 2(3): 205-12, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11256694

RESUMO

Eucaglobulin (1), a new complex of gallotannin and monoterpene, was isolated from the leaves of Eucaloptus globulus. Its structure was elucidated on the basis of spectral data. Four known hydrolyzable tannins [tellimagrandin I (2), eucalbanin C (3), 2-O-digalloyl-1,3,4-tri-O-galloyl-beta-D-glucose (4), 6-O-digalloyl-1,2,3-tri-O-galloyl-beta-D-glucose (5)], as well as gallic acid (6) and (+)-catechin (7), were also isolated. The antibacterial effects of some of these compounds were examined.


Assuntos
Medicamentos de Ervas Chinesas , Eucalyptus/química , Taninos Hidrolisáveis , Monoterpenos , Plantas Medicinais , Taninos/isolamento & purificação , Terpenos/isolamento & purificação , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Cromatografia , Humanos , Hidrólise , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Estrutura Molecular , Folhas de Planta/química , Taninos/química , Taninos/farmacologia , Terpenos/química , Terpenos/farmacologia
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