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1.
Biotech Histochem ; 96(2): 117-124, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32615821

RESUMEN

Bone cements were prepared by mixing calcium sulfate and copper sulfate in various proportions. We examined physical and physicochemical properties of the copper doped calcium sulfates and the effects of the cements on angiogenesis in vivo. Rod shaped calcium sulfate crystals were visible by scanning electron microscopy in the cement that contained no copper sulfate, whereas plate-like crystals covered the surface of the cement with high copper content. After immersion of the cements in simulated body fluid (SBF) for 1 day, X-ray diffractometric analysis showed that gypsum precipitates had formed in the copper doped calcium sulfate. The compressive strength of the cements increased from 3.3 MPa for pure calcium sulfate to 6.4 MPa for samples with copper sulfate added. Calcium ion release was greatest from pure calcium sulfate, and the rate of copper ion release was higher for cements containing the most copper. We found that 6 weeks after implantation, more blood vessels had formed around the high copper cement than for the copper-free cement. Copper doped calcium sulfate appears to be useful for application to regenerative medicine including wound healing and bone tissue engineering.


Asunto(s)
Cementos para Huesos , Sulfato de Calcio , Fosfatos de Calcio , Fuerza Compresiva , Microscopía Electrónica de Rastreo , Difracción de Rayos X
2.
Extremophiles ; 17(5): 757-65, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23818107

RESUMEN

The fungal communities associated with three bryophytes species (the liverwort Barbilophozia hatcheri, the mosses Chorisodontium aciphyllum and Sanionia uncinata) in the Fildes Region, King George Island, maritime Antarctica, were studied using clone library analysis. Fungal communities showed low diversity; the 680 clones belonged to 93 OTUs. Of these, 78 belonged to the phylum Ascomycota, 13 to the phylum Basidiomycota, 1 to the phylum Zygomycota, and 1 to an unknown phylum. Among the OTUs, the most common orders in the Ascomycota were Helotiales (42 OTUs) and Chaetothyriales (14 OTUs) and the most common orders in the Basidiomycota were Sebacinales (3 OTUs) and Platygloeales (3 OTUs). Most OTUs clustered within clades that contained phylotypes identified from samples in Antarctic or Arctic ecosystems or from bryophytes in other ecosystems. In addition, we found that host-related factor may shape the fungal communities associated with bryophytes in this region. This is the first systematic study of the fungal community in Antarctic bryophytes to be performed using culture-independent method and the results may improve understanding of the endophytic fungal evolution and ecology in the Antarctic ecosystem.


Asunto(s)
Biodiversidad , Briófitas/microbiología , Hongos/clasificación , Regiones Antárticas , Ecosistema , Hongos/genética , Hongos/aislamiento & purificación , Genes Fúngicos , Filogenia , ARN Ribosómico/genética
3.
J Enzyme Inhib Med Chem ; 22(4): 433-8, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17847709

RESUMEN

The whitening effects of the flavonoid constituents of Alpinia officinarum Hance were investigated on melanin biosynthesis in B 16 mouse melanoma cells, tyrosinase inhibition and UV absorption. The melanin content was reduced to 1.276 microg /10(5) cell for flavonoid mixture and 1.161 microg /10(5) cell for galangin while the melanin control was 1.632 microg/10(5) cell. Both flavonoid mixture and galangin reduced melanin production with an inhibition of 21.81% and 28.86% at a concentration of 26.5 microg/mL and 29 microg/mL (107.4 microM), respectively. Tyrosinase inhibition by the flavonoid mixture and galangin were higher at lower concentrations and galangin showed competitive inhibition at a concentration less than 21.23 microg/mL which was soluble. In addition, the flavonoid mixture and galangin showed a broad absorption band at 270 approximately 290 nm related to the UV-B area. These observations suggest that galangin may be a whitening agent and a promising candidate for prevention of skin cancer. This is the first full scale report on the evaluation of the whitening effect of galangin.


Asunto(s)
Flavonoides/química , Agaricales , Alpinia , Animales , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Flavonoides/farmacología , Melaninas/química , Melanoma Experimental , Ratones , Modelos Químicos , Monofenol Monooxigenasa/antagonistas & inhibidores , Monofenol Monooxigenasa/química , Mutágenos , Sales de Tetrazolio/farmacología , Tiazoles/farmacología , Rayos Ultravioleta
4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 24(5): 628-30, 2004 May.
Artículo en Chino | MEDLINE | ID: mdl-15769066

RESUMEN

The combination of mid-IR fiber optics and FTIR has made the non-invasive determination of samples in situ, with long distances, and in vivo possible. In this paper domestic mid-IR fiber optics was improved to investigate the transmission ability of fiber optics and its application to the sample determination. New design was applied to obtaining one bare fiber optics, which has a minor energy loss and higher signal-to-noise ratio. The spectra of H2O/EtOH and tissue samples were measured using the new designed fiber optics and the results show that home-made mid-IR fiber optics can be applied to the field of determination of general and biological samples.

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