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1.
J Magn Reson Imaging ; 49(6): 1610-1616, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30328211

RESUMEN

BACKGROUND: Conventional diffusion-weighted imaging (DWI) with high b-values may improve lesion conspicuity, but with a low signal intensity and thus a low signal-to-noise ratio (SNR). The voxelwise computed DWI (vcDWI) may generate high-quality images with a strong lesion signal and low background. PURPOSE: To evaluate the feasibility and diagnostic performance of vcDWI. STUDY TYPE: Retrospective. POPULATION: In all, 67 patients with 72 lesions, 33 malignant and 39 benign. FIELD STRENGTH/SEQUENCE: 3T, including T2 /T1 , DWI with two b-values, and dynamic contrast-enhanced MRI (DCE-MRI). ASSESSMENT: Computed DWI (cDWI) with high b-values of 1500, 2000, 2500 s/mm2 (cDWI1500 , cDWI2000 , cDWI2500 ) and vcDWI were generated from measured DWI (mDWI). The mDWI, cDWIs and vcDWI were evaluated by three readers independently to determine lesion conspicuity, background signal suppression, overall image quality using 1-5 rating scales, as well as to give BI-RADS scores. The mean apparent diffusion coefficient (ADC) value for each lesion was measured. STATISTICAL TESTS: Agreement among the three readers was evaluated by the intraclass correlation coefficient. Receiver operating characteristic (ROC) analysis was performed to compare the diagnostic performance based on reading of mDWI, cDWIs, vcDWI, and the measured ADC values. RESULTS: vcDWI provided the best lesion conspicuity compared with mDWI and cDWIs (P < 0.005). For overall image quality, vcDWI was significantly better than cDWI (P < 0.005), but not significantly better compared with mDWI for two readers (P = 0.037 and P = 0.013) and significantly worse for the third reader (P < 0.005). Background signal suppression was the best on cDWI2500 , and better on vcDWI than on mDWI, cDWI1500 , and cDWI2000 . The AUC value for differential diagnosis was 0.868 for mDWI, 0.862 for cDWI1500 , 0.781 for cDWI2000 , 0.704 for cDWI2500 , 0.946 for vcDWI, 0.704 for ADC value, and 0.961 for DCE-MRI. DATA CONCLUSION: vcDWI was implemented without increasing scanning time, and it provided excellent lesion conspicuity for detection of breast lesions and assisted in differentiating malignant from benign breast lesions. LEVEL OF EVIDENCE: 4 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Mama/patología , Imagen de Difusión por Resonancia Magnética , Adolescente , Adulto , Anciano , Algoritmos , Área Bajo la Curva , Biopsia , Medios de Contraste , Estudios de Factibilidad , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Persona de Mediana Edad , Variaciones Dependientes del Observador , Curva ROC , Estudios Retrospectivos , Procesamiento de Señales Asistido por Computador , Relación Señal-Ruido , Adulto Joven
2.
Regul Toxicol Pharmacol ; 65(3): 294-303, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23321397

RESUMEN

High molecular weight chitosan (HMWCS) is effective at hemostasis and wound healing, and will be potentially used on injured internal organs. To study its prenatal and developmental effect in vivo, forty-four ICR pregnant mice per group were singly injected intraperitoneally at 0, 125, 500 or 2000 mg/kg body weight, respectively, on gestation day 6 (GD6). Clinical signs, reproductive capacity, fetus and infant developments, and histopathological changes were then observed. The results showed that the treatment of HMWCS could decrease body weights and food consumptions, and induce diarrhea, vaginal bleeding, and some other adverse effects in F0 mice. For the emaciation and threatened abortion of pregnant mice, the numbers of live fetuses and early resorption were reduced significantly in HMWCS groups. However, the developments of F1 and F2 mice were not affected, except for lower weights of the body and some organs. In addition, the NOAEL of HMWCS in maternal toxicity was considered to be less than 125 mg/kg, and the NOAEL in developmental toxicity was 125 mg/kg.


Asunto(s)
Quitosano/toxicidad , Embrión de Mamíferos/efectos de los fármacos , Desarrollo Embrionario/efectos de los fármacos , Desarrollo Fetal/efectos de los fármacos , Hemostáticos/toxicidad , Teratógenos/toxicidad , Anomalías Inducidas por Medicamentos , Animales , Peso Corporal/efectos de los fármacos , Quitosano/química , Quitosano/clasificación , Diarrea/inducido químicamente , Ingestión de Alimentos/efectos de los fármacos , Femenino , Hemostáticos/química , Hemostáticos/clasificación , Exposición Materna , Ratones , Ratones Endogámicos ICR , Peso Molecular , Embarazo , Teratógenos/química , Teratógenos/clasificación
3.
Mar Drugs ; 8(7): 1962-87, 2010 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-20714418

RESUMEN

Chitosan has received much attention as a functional biopolymer for diverse applications, especially in pharmaceutics and medicine. Our recent efforts focused on the chemical and biological modification of chitosan in order to increase its solubility in aqueous solutions and absorbability in the in vivo system, thus for a better use of chitosan. This review summarizes chitosan modification and its pharmaceutical/biomedical applications based on our achievements as well as the domestic and overseas developments: (1) enzymatic preparation of low molecular weight chitosans/chitooligosaccharides with their hypocholesterolemic and immuno-modulating effects; (2) the effects of chitin, chitosan and their derivatives on blood hemostasis; and (3) synthesis of a non-toxic ion ligand--D-Glucosaminic acid from oxidation of D-Glucosamine for cancer and diabetes therapy.


Asunto(s)
Quitina/química , Quitosano/química , Portadores de Fármacos/química , Animales , Sistemas de Liberación de Medicamentos , Glucosamina/análogos & derivados , Glucosamina/química , Humanos , Oligosacáridos/química , Solubilidad
4.
Diabetes Metab Syndr Obes ; 4: 137-40, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21779145

RESUMEN

BACKGROUND: The purpose of this study was to assess the in vivo ability of glucosaminic acid-cobalt (II) chelate to reduce glycemia. METHODS: Different concentrations of chelate solution were administrated to mice with diabetes induced by streptozotocin. RESULTS: Daily oral administration of chelate solution 0.4 mL at various concentrations (0.32-0.4 g/mL) led to reduction in water intake by the diabetic mice after 5 days of treatment, with a subsequent reduction in glucose levels observed 2 weeks later. Daily food intake was related to both chelate concentration as well as glycemia reduction. The food intake of mice treated with glucosaminic acid-cobalt (II) chelate solution was 1.5-fold that of untreated mice. CONCLUSION: Glucosaminic acid-cobalt chelate was effective as an antidiabetes agent; its efficacy was proportional to treatment period .The chelated form expressed much less toxicity compared to cobalt only, and stimulated subsequent food intake after daily administration.

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