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1.
Ann Pediatr Endocrinol Metab ; 20(2): 102-5, 2015 06.
Artigo em Inglês | MEDLINE | ID: mdl-26191515

RESUMO

Vitamin D deficient rickets is generally known to occur in breast fed infants. And excessive phosphate ingestion is a main cause of late onset hypocalcemia in formula fed infants. Here we introduce 45-day-old formula fed hypocalcemic twins with recurrent seizure attacks. They were diagnosed as having both of vitamin D deficient rickets and hyperphosphatemia. Radiologic findings indicated mild rickets and the twins were treated with calcium and alfacalcidol. After 3-5 months of oral supplementation, medication was discontinued in both twins. They showed normal growth and calcium, phosphorus, and vitamin D levels during the 6-month follow-up period. Twins can be at risk for hypocalcemia because of their high risk of vitamin D deficiency, low birth weight, and premature birth. Therefore twin pregnant women need ingestion of sufficient vitamin D and calcium.

2.
Carbohydr Polym ; 111: 822-9, 2014 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-25037421

RESUMO

A fucoidan extracted from Sargassum fulvellum, was degraded by ultrasound (US) or electron beam (EB) irradiation in the presence of hydrogen peroxide aqueous solution. From the energetic point of view, the most effective method for the fucoidan degradation was found to be EB radiation method in H2O2 with a yield of scission Gs 3.310 × 10(-8)mol/J at the reaction condition of 1.5% hydrogen peroxide and irradiation 2.5 kGy. The degradation took place by the formation of a reactive hydroxyl radical due to the dissociation of H2O2 in the presence of US or EB. The low molecular weight fucoidans (LMWFs) prevented P-selectin binding to Sialyl Lewis X with an IC50 (inhibitory concentration 50) of 20 nM as compared to 400 nM for heparin and 25,000 nM for dextran sulfate. The LMWFs showed no hemolytic activity at concentrations up to 950 µg/ml.


Assuntos
Polissacarídeos/química , Polissacarídeos/farmacologia , Sargassum/química , Sobrevivência Celular/efeitos dos fármacos , Elétrons , Hemólise/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana , Humanos , Peróxido de Hidrogênio/química , Selectina-P/metabolismo , Polissacarídeos/isolamento & purificação , Sonicação
3.
Molecules ; 16(10): 8143-51, 2011 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-21952496

RESUMO

DNA-mediated gold nanoparticles were prepared by chemical reduction of DNA-Au(III) complex. The DNA-Au(III) was first formed by reacting DNA with HAuCl4 at a pH of 5.6. The complex in solution was reacted with hydrazine reducing Au(III) to Au. The reduced Au formed nanodimensional aggregates. The particle distributions were obtained by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). This method resulted in a rather uniform dispersion of Au nanoparticles of near-spherical shape and 45~80 nm in diameter. Gold nanoparticles were embedded and stabilized by DNA.


Assuntos
DNA/química , Ouro/química , Nanopartículas Metálicas/química , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão
4.
J Nanosci Nanotechnol ; 10(5): 3478-83, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20358982

RESUMO

A fluorescence susceptible water-soluble paclitaxel was synthesized by a condensation reaction between PEGylated paclitaxel (namely, PP7) and 1-pyrene butyric acid (PBA) in order to obtain a better understanding of the mechanism of action of paclitaxel as well as of the environment of the paclitaxel-binding site. The reaction was performed successfully and the resulting paclitaxel was characterized by FT-NMR, analytical-HPLC, UV spectro photometry, and fluorescence spectrometry. The synthesized paclitaxel analogue showed a high susceptibility to fluorescence in both excitation and emission spectra. And we have investigated the time-resolved fluorescence behavior of them in different solvents and at different excitation wavelengths.


Assuntos
Corantes Fluorescentes/química , Paclitaxel/química , Pró-Fármacos/química , Água/química , Antineoplásicos Fitogênicos/química , Solubilidade , Coloração e Rotulagem/métodos
5.
J Biomater Sci Polym Ed ; 19(3): 311-24, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18325233

RESUMO

A new series of poly(ethylene glycol)(PEG)-paclitaxel conjugates that increases water solubility of paclitaxel was synthesized. We developed well-designed self-immolating linkers between a drug and a water-soluble polymer moiety which gave an extremely rapid hydrolysis rate to convert a pro-drug into a parent drug without any reduction in drug efficacy. The self-immolating spacer groups were introduced between the solubilizing PEG and C7-OH of paclitaxel in order to control the rate of enzymatic hydrolysis. All these pro-drugs had a water-solubility of 400 mg/ml or more compared with a solubility of about 0.01 mg/ml. The rate of hydrolysis for the pro-drugs in rat plasma showed considerable variation of t((1/2)) ranging from 0.94 min to 42.7 min. To evaluate the anti-tumor efficacy of the pro-drug which had the fastest enzymatic hydrolysis rate, the growth inhibitory effect (IC(50)), the anti-tumor activity and the anti-metastatic potential of the pro-drug were examined. The pro-drug was potent to inhibit the growth of various cancer cell lines, such as human lung, ovarian, colon and melanoma cancer cells. On the development of melanoma lung colonies in C57B/6 mice following intravenous administration of metastatic murine B16/F10 melanoma cells, the pro-drug seems to be more efficacious than paclitaxel. The reduction of the number of melanoma lung colonies was 46.9% (dose: 5 mg/kg) with pure paclitaxel, and 24.5%, and 40.0% with the pro-drug in the dose of 0.71 mg paclitaxel equivalent/kg and 1.42 mg paclitaxel equivalent/kg, respectively.


Assuntos
Antineoplásicos Fitogênicos/síntese química , Paclitaxel/química , Pró-Fármacos/síntese química , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Portadores de Fármacos , Humanos , Hidrólise , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Polietilenoglicóis/química , Pró-Fármacos/química , Pró-Fármacos/farmacologia , Solubilidade , Água/química
6.
J Nanosci Nanotechnol ; 8(10): 5479-84, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19198481

RESUMO

Poly(ethylene vinylacetate)/clay nanocomposites were prepared by a "one pot" method, using Cloisite-Na+ with a compatibilizer at different ratios. The nano-composite prepared was used to prepare a flame retarding polymeric foams. Flame retarding properties were examined by the limiting oxygen index and cone calorimetry. CO and CO2 production were reduced remarkably by using the nanocomposite in EVA blends.

7.
J Nanosci Nanotechnol ; 8(10): 5610-3, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19198510

RESUMO

Cross-linking of low-density polyethylene (PE)/organo-nanocomposite blends by electron beam irradiation was studied with the aim of flame retarding foam production by thermal expansion. Flammability and thermal properties of the obtained foams were studied and it was found that relatively low doses up to 42.5 kGy could be used leading to a product with excellent surface appearance and flame retardancy.

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