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1.
Phys Med Biol ; 68(24)2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-37549670

RESUMEN

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.


Asunto(s)
Terapia de Protones , Humanos , Dosis de Radiación , Terapia de Protones/efectos adversos , Terapia de Protones/métodos , Sincrotrones , Método de Montecarlo , Dosificación Radioterapéutica
2.
Molecules ; 26(2)2021 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-33440779

RESUMEN

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.


Asunto(s)
Taninos Hidrolizables/análisis , Polygonaceae/química , Proantocianidinas/análisis , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Polifenoles/análisis , Rizoma/química
3.
Nat Prod Res ; 35(24): 5778-5785, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33107331

RESUMEN

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.


Asunto(s)
Antozoos , Talaromyces , Animales , Escherichia coli , Polifenoles/farmacología , Staphylococcus aureus
4.
Chin J Nat Med ; 18(4): 250-255, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32402400

RESUMEN

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.


Asunto(s)
Penicillium/química , Esteroides/química , Esteroides/aislamiento & purificación , Organismos Acuáticos , Línea Celular Tumoral , Humanos , Estructura Molecular
5.
Innate Immun ; 26(6): 505-513, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32456598

RESUMEN

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.


Asunto(s)
Antígenos Dermatofagoides/inmunología , Proteínas de Artrópodos/inmunología , Cisteína Endopeptidasas/inmunología , Células Epiteliales/inmunología , Inflamación/inmunología , Proteína 1 Similar al Receptor de Interleucina-1/metabolismo , Interleucina-33/metabolismo , Mucosa Nasal/inmunología , Rinitis Alérgica/inmunología , Apoptosis , Células Cultivadas , Citocinas/metabolismo , Progresión de la Enfermedad , Humanos , Mediadores de Inflamación/metabolismo , Proteína 1 Similar al Receptor de Interleucina-1/genética , Interleucina-33/genética , Sistema de Señalización de MAP Quinasas , ARN Interferente Pequeño/genética
6.
Diabetes Ther ; 9(6): 2393-2398, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30377995

RESUMEN

INTRODUCTION: Conbercept is a new anti-vascular endothelial growth factor drug approved for the treatment of age-related macular degeneration by the China Food and Drug Administration (CFDA) in 2013. In this study, we for the first time evaluated the concentrations of vascular endothelial growth factor (VEGF) and placental growth factor (PlGF) after patients with proliferative diabetic retinopathy were treated with intravitreal conbercept (IVC) injection. METHODS: Sixteen patients with proliferative diabetic retinopathy were randomly divided into two equal groups (A and B). Nine patients with rhegmatogenous retinal detachment were used as the control group. The patients in group A received 0.5 mg IVC and their aqueous humor was collected. After 7 days, all patients underwent vitrectomy, and their aqueous and vitreous humor were collected. RESULTS: In the aqueous humor, the concentrations of VEGF and PlGF were higher pre- than post-IVC injection in group A. Similarly, the concentrations of VEGF and PlGF in group A (pre-IVC) and group B were higher than those in the control group. In vitreous humor, the concentrations of VEGF and PlGF were higher in group B than those in the control group, and the concentrations of VEGF were lower in group A (post-IVC) than those in group B. CONCLUSIONS: Our study proved that the concentration of VEGF and PlGF reduced after IVC injection in aqueous humor. However, the concentration of PlGF did not reduce after IVC injection in vitreous humor.

7.
J Asian Nat Prod Res ; 17(9): 908-14, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25978098

RESUMEN

Two new triterpenoid saponins (1 and 2) were isolated from the stems of Ilex cornuta, along with two known triterpenoids (3 and 4). The structures of compounds 1 and 2 were determined as ursane-12,19-diene-28-oic acid 3ß-O-ß-D-glucuronopyranoside-6-O-methyl ester (1), 3α,23α-dihydroxy-olean-9(11),12-diene-28-oic acid 28-O-ß-D-glucopyranosyl ester (2), on the basis of hydrolysis and spectral evidence, including 1D and 2D NMR and high resolution electrospray ionization mass spectrometry (HR-ESI-MS) analyses. Protective effects of compounds 1-4 were tested against H(2)O(2)-induced H9c2 cardiomyocyte injury, and the data showed that all these compounds had no cell-protective effect.


Asunto(s)
Ilex/química , Saponinas/aislamiento & purificación , Triterpenos/aislamiento & purificación , Peróxido de Hidrógeno/farmacología , Estructura Molecular , Miocitos Cardíacos/efectos de los fármacos , Resonancia Magnética Nuclear Biomolecular , Raíces de Plantas/química , Saponinas/química , Estereoisomerismo , Triterpenos/química
8.
J Asian Nat Prod Res ; 17(8): 800-7, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25628037

RESUMEN

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.


Asunto(s)
Antineoplásicos Fitogénicos/aislamiento & purificación , Antineoplásicos Fitogénicos/farmacología , Camellia/química , Medicamentos Herbarios Chinos/aislamiento & purificación , Medicamentos Herbarios Chinos/farmacología , Saponinas/aislamiento & purificación , Saponinas/farmacología , Triterpenos/aislamiento & purificación , Triterpenos/farmacología , Antineoplásicos Fitogénicos/química , Ensayos de Selección de Medicamentos Antitumorales , Medicamentos Herbarios Chinos/química , Humanos , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Raíces de Plantas/química , Saponinas/química , Triterpenos/química
9.
Chem Pharm Bull (Tokyo) ; 58(10): 1391-4, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20930410

RESUMEN

A chemical investigation on a South China Sea gorgonian, Menella sp. resulted in the isolation and elucidation of menellin A (1), a highly oxygenated racemate with C(8) skeleton, and a polyhydroxylated steroid, menellsteroid C (2), along with eight known compounds (3-10). The structures of the new compounds were elucidated by means of MS, 1D and 2D NMR spectra, and the relative stereochemistry of 1 was determined by X-ray single-crystal diffraction analysis. In addition, compound 7 was isolated as a new natural product. Compounds 1-3 and 7 were selected to test the anti-inflammatory inhibition against lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW264.7 macrophages. 1 and 3 exhibited modest inhibitory effects with IC(50) of 71.3, 33.9 µM, respectively, compared to the positive control aminoguanidine (IC(50) 25.0 µM).


Asunto(s)
Antozoos/química , Antiinflamatorios/química , Ciclopentanos/química , Esteroides/química , Animales , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/farmacología , Línea Celular , China , Cristalografía por Rayos X , Ciclopentanos/aislamiento & purificación , Ciclopentanos/farmacología , Lipopolisacáridos/farmacología , Espectroscopía de Resonancia Magnética , Ratones , Conformación Molecular , Óxido Nítrico/metabolismo , Esteroides/aislamiento & purificación , Esteroides/farmacología
10.
Zhong Yao Cai ; 33(4): 545-6, 2010 Apr.
Artículo en Chino | MEDLINE | ID: mdl-20845780

RESUMEN

OBJECTIVE: To study the chemical constituents from the marine sponge Iotrochota sp. METHODS: The compounds were isolated and purified by various column chromatography methods, and their structure wer identified cholesterol (1), nonadecyl ethers of glycerol (2), p-hydroxybenzaldehyde (3), (E)-4-(3,4-dihydroxyphenyl) but-3-en-2-one (4), 3,4-dihydroxybenzaldehyde (5), ethyl vanillin (6), hendecanoic acid (7), tricosane (8). CONCLUSION: All compounds are isolated from marine sponge Iotrochota sp. for the first time.


Asunto(s)
Alcanos/aislamiento & purificación , Benzaldehídos/aislamiento & purificación , Colesterol/aislamiento & purificación , Poríferos/química , Alcanos/química , Animales , Benzaldehídos/química , Catecoles/química , Catecoles/aislamiento & purificación , Colesterol/química , Espectroscopía de Resonancia Magnética , Estructura Molecular
11.
Zhong Yao Cai ; 33(1): 60-1, 2010 Jan.
Artículo en Chino | MEDLINE | ID: mdl-20518307

RESUMEN

OBJECTIVE: To study the chemical constituents in the fresh marine sponge Spongilla Wagner. METHODS: Compounds were separated and purified through various chromatographic methods and their structures were identified by spectroscopic data. RESULTS: Seven compounds were isolated and identified as 4-hydroxybenzoic acid (I), p-hydroxycinnamic acid (II), Pyrimidine-2, 4 (1H, 3H)-dione (III), Ferulic acid methyl ester (IV), Dodecyl ethers of glycerol (V), Tetracosane( VI). CONCLUSION: All compounds are isolated from this sponge for the first time.


Asunto(s)
Ácidos Cumáricos/aislamiento & purificación , Materia Medica/química , Parabenos/aislamiento & purificación , Poríferos/química , Alcanos/química , Alcanos/aislamiento & purificación , Animales , Cromatografía en Capa Delgada , Ácidos Cumáricos/química , Parabenos/química , Propionatos , Mostaza de Uracilo/química , Mostaza de Uracilo/aislamiento & purificación
12.
J Microencapsul ; 27(4): 345-54, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20380482

RESUMEN

A convenient and effective 'ultrasonic dispersion method' was used to fabricate vector/DNA complexes encapsulated microspheres. Polyamidoamine (PAMAM) dendrimer/DNA complexes protected by a water-soluble polymer, poly-alpha,beta-[N-(2-hydroxyethyl)-L-aspartamide] (PHEA), were encapsulated in a polymer film mainly composed of cholic acid functionalized star poly(DL-lactide), which degraded through surface erosion mechanism with a fast degradation rate. The PAMAM/DNA complexes encapsulated polymer film was then immersed in ethanol and ultrasonicated to afford the microspheres. The in vitro gene transfections showed PAMAM/DNA complexes protected by PHEA exhibited a much higher transfection activity compared with PAMAM/DNA complexes without the protection by PHEA. The expressions of pGL3-Luc in HEK293 cells could be effectively mediated by the polymer film and microspheres with the presence of PHEA. The ultrasonic dispersion method, which did not involve toxic organic solvents, could keep the bioactivity of DNA and offer good control over the size of microspheres.


Asunto(s)
Implantes Absorbibles , ADN/química , Dendrímeros/química , Regulación de la Expresión Génica , Técnicas de Transferencia de Gen , Microesferas , Línea Celular , Humanos , Microscopía Confocal , Estructura Molecular , Tamaño de la Partícula , Propiedades de Superficie
13.
Mol Biosyst ; 5(6): 629-37, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19462020

RESUMEN

Low transfection efficiency and inactivation by serum are the major drawbacks for cationic polymers when used as non-viral gene vectors. Here, a series of N-succinyl-chitosan-graft-polyethylenimine (NSC-g-PEI) copolymers with different compositions were synthesized through grafting low molecular weight PEI (800 Da) to N-succinyl-chitosan. An agarose gel electrophoresis assay showed NSC-g-PEIs had good binding capability with DNA and the particle size of the NSC-g-PEI-DNA complexes was between 150 to 300 nm as determined by a Zeta sizer. In vitro transfection of NSC-g-PEI-DNA complexes for 293T, HeLa and CHO cells was investigated. It was found that the transfection efficiency of NSC-g-PEI-DNA complexes was higher than that of DNA combined PEI (25 kDa) and the transfection efficiency increased with the increasing GD of PEI. More importantly, the NSC-g-PEI-DNA complexes were stable and the transfection efficiency was not affected obviously in the presence of serum with different concentrations. In addition, NSC-g-PEIs had a lower cytotoxicity than PEI (25 kDa) and the toxicity increased with increasing GD of PEI. The NSC-g-PEI copolymers will have a good potential as efficient non-viral gene vectors in the presence of serum.


Asunto(s)
Quitosano/química , ADN/genética , Polietileneimina/química , Transfección/métodos , Animales , Células CHO , Línea Celular , Supervivencia Celular/efectos de los fármacos , Cricetinae , Cricetulus , Medios de Cultivo/farmacología , ADN/química , ADN/ultraestructura , Electroforesis en Gel de Agar , Células HeLa , Humanos , Sustancias Macromoleculares/química , Microscopía Electrónica de Rastreo , Peso Molecular , Tamaño de la Partícula , Reproducibilidad de los Resultados , Suero
14.
Chem Pharm Bull (Tokyo) ; 56(6): 858-60, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18520096

RESUMEN

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.


Asunto(s)
Saponinas/aislamiento & purificación , Triterpenos/aislamiento & purificación , Zygophyllum/química , Animales , Línea Celular , Hidrólisis , Macrófagos/metabolismo , Espectroscopía de Resonancia Magnética , Ratones , Conformación Molecular , Óxido Nítrico/antagonistas & inhibidores , Óxido Nítrico/biosíntesis , Corteza de la Planta/química , Extractos Vegetales/química , Espectrometría de Masa por Ionización de Electrospray , Espectrofotometría Infrarroja , Sales de Tetrazolio , Tiazoles
15.
Chem Pharm Bull (Tokyo) ; 56(2): 189-91, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18239306

RESUMEN

Two new alkaloids, Capparin A (1) and B (2), along with seven known compounds 6-methoxyindoline-2,3-dione (3), wogonin (4), oroxylin A (5), kaempferol (6), apigenin (7), quercetin (8) and luteolin (9), were isolated from the whole plant of Capparis himalayensis. Their structures have been established on the basis of spectral methods and the structure of 1 was confirmed by X-ray crystallographic analysis.


Asunto(s)
Alcaloides/análisis , Capparis/química , Indoles/análisis , Cristalografía por Rayos X , Etanol , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Extractos Vegetales/análisis , Solventes , Espectrometría de Masa por Ionización de Electrospray , Espectrofotometría Ultravioleta
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