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1.
Phys Med Biol ; 68(24)2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37549670

RESUMO

Objective. Non-primary radiation doses to normal tissues from proton therapy may be associated with an increased risk of secondary malignancies, particularly in long-term survivors. Thus, a systematic method to evaluate if the dose level of non-primary radiation meets the IEC standard requirements is needed.Approach. Different from the traditional photon radiation therapy system, proton therapy systems are composed of several subsystems in a thick bunker. These subsystems are all possible sources of non-primary radiation threatening the patient. As a case study, 7 sources in the P-Cure synchrotron-based proton therapy system are modeled in Monte Carlo (MC) code: tandem injector, injection, synchrotron ring, extraction, beam transport line, scanning nozzle and concrete reflection/scattering. To accurately evaluate the synchrotron beam loss and non-primary dose, a new model called the torus source model is developed. Its parametric equations define the position and direction of the off-orbit particle bombardment on the torus pipe shell in the Cartesian coordinate system. Non-primary doses are finally calculated by several FLUKA simulations.Main results. The ratios of summarized non-primary doses from different sources to the planned dose of 2 Gy are all much smaller than the IEC requirements in both the 15-50 cm and 50-200 cm regions. Thus, the P-Cure synchrotron-based proton therapy system is clean and patient-friendly, and there is no need an inner shielding concrete between the accelerator and patient.Significance. Non-primary radiation dose level is a very important indicator to evaluate the quality of a PT system. This manuscript provides a feasible MC procedure for synchrotron-based proton therapy with new beam loss model. Which could help people figure out precisely whether this level complies with the IEC standard before the system put into clinical treatment. What' more, the torus source model could be widely used for bending magnets in gantries and synchrotrons to evaluate non-primary doses or other radiation doses.


Assuntos
Terapia com Prótons , Humanos , Doses de Radiação , Terapia com Prótons/efeitos adversos , Terapia com Prótons/métodos , Síncrotrons , Método de Monte Carlo , Dosagem Radioterapêutica
2.
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
3.
Nat Prod Res ; 35(24): 5778-5785, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33107331

RESUMO

Two new polyphenols, talaversatilis A (1) and B (2), together with fifteen known compounds (3-17) were isolated from the extract of the culture broth of a soft coral-derived fungus Talaromyces sp. SCSIO 041201. The structures of these compounds were elucidated by the extensive analyses of spectroscopic data and by comparison with the reported literature. Antifouling and antibacterial activities of all purified compounds were tested and evaluated. Compounds 5 and 6 showed antifouling activity towards Bugula neritina larva, with LC50 values of 3.86 µg/mL and 3.05 µg/mL, respectively. Compounds 7, 8, 10 and 13 exhibited significant antibacterial activities against E. coli, MRSA, S. aureus and E. faecalis, with MIC values ranging from 0.45 to 15.6 µg/mL.


Assuntos
Antozoários , Talaromyces , Animais , Escherichia coli , Polifenóis/farmacologia , Staphylococcus aureus
4.
Chin J Nat Med ; 18(4): 250-255, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32402400

RESUMO

Penicildiones A-D (1-4), four new steroids derivatives together with three known compounds including 16α-methylpregna-17α,19-dihydroxy-(9,11)-epoxy-4-ene-3,18-dione-20-acetoxy (5), stachybotrylactone B (6) and stachybotrin (7) were isolated from the soft coral-derived fungus Penicillium sp. SCSIO41201, cultured in the 1% NaCl PDB substrate. Their structures were determined through spectroscopic methods and X-ray crystallography. Biological evaluation results revealed that 6 exhibited significant cytotoxic activity against HL-60, K562, MOLT-4, ACHN, 786-O, and OS-RC-2 cell lines with IC50 values of 5.23, 4.12, 4.31, 23.55, 7.65 and 10.81 µmol·L-1, respectively, while other compounds showed weak or no cytotoxicity at 50 µmol·L-1.


Assuntos
Penicillium/química , Esteroides/química , Esteroides/isolamento & purificação , Organismos Aquáticos , Linhagem Celular Tumoral , Humanos , Estrutura Molecular
5.
Innate Immun ; 26(6): 505-513, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32456598

RESUMO

Allergic rhinitis (AR) is a nasal mucosal inflammatory disease mediated by environmental allergens. At present, the relationship between the IL-33/ST2 axis, ERK1/2 pathway and AR progression needs further exploration. In our study, an AR model was constructed in vitro by treating HNEpC cells with Der p1. qRT-PCR was applied to assess the mRNA levels of IL-33, ST2, TNF-α, IL-6, and IL-8. Western blotting was used to measure the protein levels of IL-33, ST2, and the downstream proteins p-ERK1/2, ERK1/2, p-RSK, and RSK. IL-6, IL-8, IL-33, and TNF-α protein levels in cell supernatants were evaluated by ELISA. Flow cytometry was performed to check cell apoptosis of HNEpC in the presence or absence of Der p1. Our results indicate that the relative levels of IL-33, ST2, TNF-α, IL-6, and IL-8 were increased significantly in the AR model group. The above effects were notably reversed after transfection with shIL-33 or shST2. IL-33 stimulation further resulted in the increase in both ST2 and inflammation-associated cytokines, and these effects were restored after shST2 treatment. Also, the levels of inflammatory factors induced by IL-33 stimulation or ST2 overexpression were reversed after applying an ERK1/2 pathway blocker. In conclusion, IL-33/ST2 mediated inflammation of nasal mucosal epithelial cells by inducing the ERK1/2 pathway.


Assuntos
Antígenos de Dermatophagoides/imunologia , Proteínas de Artrópodes/imunologia , Cisteína Endopeptidases/imunologia , Células Epiteliais/imunologia , Inflamação/imunologia , Proteína 1 Semelhante a Receptor de Interleucina-1/metabolismo , Interleucina-33/metabolismo , Mucosa Nasal/imunologia , Rinite Alérgica/imunologia , Apoptose , Células Cultivadas , Citocinas/metabolismo , Progressão da Doença , Humanos , Mediadores da Inflamação/metabolismo , Proteína 1 Semelhante a Receptor de Interleucina-1/genética , Interleucina-33/genética , Sistema de Sinalização das MAP Quinases , RNA Interferente Pequeno/genética
6.
J Asian Nat Prod Res ; 17(8): 800-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25628037

RESUMO

Two new triterpenoid saponins, oleiferoside N and oleiferoside O, were isolated from the EtOH extract from the roots of Camellia oleifera C. Abel. Their structures were elucidated as 16α-acetoxy-21ß,22α-O-diangeloyloxy-23,28-dihydroxyolean-12-ene 3ß-O-ß-D-xylopyranosyl-(1 → 3)-α-L-arabinopyranosyl-(1 → 3)-ß-D-glucuronopyranoside (1), 16α-acetoxy-21ß-O-angeloyloxy-23,28-dihydroxy-22α-O-(2-methylbutanoyloxy)olean-12-ene 3ß-O-ß-D-xylopyranosyl-(1 → 3)-α-L-arabinopyranosyl-(1 → 3)-ß-D-glucuronopyranoside (2), on the basis of spectroscopic analyses (IR, ESI-MS, HR-ESI-MS, 1D and 2D NMR) and acid hydrolysis. Both were characterized to be oleanane-type saponins with sugar moieties linked to C-3 of the aglycone. Cytotoxic activities of two saponins were evaluated against four human tumor cell lines (A549, B16, BEL-7402, and MCF-7) by using the MTT in vitro assay. Compounds 1 and 2 showed moderate cytotoxic activities toward the tested cell lines.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Camellia/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Saponinas/isolamento & purificação , Saponinas/farmacologia , Triterpenos/isolamento & purificação , Triterpenos/farmacologia , Antineoplásicos Fitogênicos/química , Ensaios de Seleção de Medicamentos Antitumorais , Medicamentos de Ervas Chinesas/química , Humanos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Raízes de Plantas/química , Saponinas/química , Triterpenos/química
7.
Chem Pharm Bull (Tokyo) ; 56(6): 858-60, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18520096

RESUMO

Two new triterpenoid saponins, zygophylosides O (1) and P (2), have been isolated from the barks of Zygophyllum fabago L. Their structures were elucidated as 3beta-[(2-O-sulfo-beta-D-xylopyranosyl)oxy]urs-12-ene-27,28-dioic acid and 3beta-[(2-O-sulfo-beta-D-xylopyranosyl)oxy]urs-12-ene-27,28-dioic acid 28-beta-D-glucopyranoside, respectively, by spectral and chemical evidence. Compound 1 showed weaker Nitric Oxide (NO) inhibitory activity.


Assuntos
Saponinas/isolamento & purificação , Triterpenos/isolamento & purificação , Zygophyllum/química , Animais , Linhagem Celular , Hidrólise , Macrófagos/metabolismo , Espectroscopia de Ressonância Magnética , Camundongos , Conformação Molecular , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Casca de Planta/química , Extratos Vegetais/química , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Infravermelho , Sais de Tetrazólio , Tiazóis
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