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1.
Appl Radiat Isot ; 127: 35-40, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28501718

RESUMEN

Several ZnB2O4 powder samples having dopants concentrations of 0.1, 0.01, 0.04wt% Ce and La were prepared using the nitric acid method via the starting oxides. Several complementary methods such as powder X-ray diffraction (XRD), thermal analyses environmental scanning electron microscopy (ESEM), Radioluminescence (RL) and Cathodoluminescence (CL) techniques were used. Unique luminescence properties of Ce doped ZnB2O4 powder samples are reported for the first time. A new luminescence bands appearing in red part of the spectrum and having all the characteristics of Ce3+ were obtained from RL results. Changing the Ce and La concentration of 0.01-0.1wt% leads to an increase in RL and CL intensities of Ce3+ and La3+ ions and also CL emission spectra of ZnB2O4 show gradual shift towards longer wavelength. When we compare the luminescence intensity of the samples it is seen that Ce doped ZnB2O4 has the highest intense whereas La doped ZnB2O4 has the lowest one. However, emission spectra of both Ce and La doped samples kept unchanged.

2.
Appl Radiat Isot ; 114: 114-20, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27235885

RESUMEN

Here, we report our results referring to the preparation of Ce doped Y2.22MgGa2Al2SiO12, Y1.93MgAl4SiO12 and Y2.22Gd0.75Ga2Al3O12 using solid state reaction at high temperature. Several complementary methods (i.e. powder x-ray diffraction (XRPD), energy dispersive analysis of X-rays (EDX), scanning electron microscopy (SEM) and Fourier transforms infrared spectroscopy (FTIR)) were studied to examine the effects of the synthesis procedure on the morphology and structure. XRD analyses revealed that all compounds include yttrium aluminate phase with garnet structure. Cathodoluminescence (CL), radioluminescence (RL) and photoluminescence (PL) measurements were carried out for clarification of relationship between host lattice defects and the spectral luminescence emissions. Luminescence emission of phosphors is peaked at 530nm assigned to 5d-4f transitions of the dopant Ce(3+) ions with a broad emission band in 400-700nm range. Under electron irradiation, the emission spectrum of Ce doped (YGd)3Ga2Al3O12 is well defined and has a characteristic fairly narrow and sharp emission band peaking at 312nm and 624nm corresponding to transition of (6)P7/2 →(8)S7/2 and (6)GJ→(6)PJ (Gd(3+)), respectively. We suggest some of phosphors might be excellent phototherapy phosphor materials under electron excitation.

3.
Antimicrob Agents Chemother ; 60(6): 3291-300, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26976872

RESUMEN

Candida glabrata isolates have reduced in vitro susceptibility to azoles, which raises concerns about the clinical effectiveness of fluconazole for treating bloodstream infection (BSI) by this Candida species. We aimed to evaluate whether the choice of initial antifungal treatment (fluconazole versus echinocandins or liposomal amphotericin B [L-AmB]-based regimens) has an impact on the outcome of C. glabrata BSI. We analyzed data from a prospective, multicenter, population-based surveillance program on candidemia conducted in 5 metropolitan areas of Spain (May 2010 to April 2011). Adult patients with an episode of C. glabrata BSI were included. The main outcomes were 14-day mortality and treatment failure (14-day mortality and/or persistent C. glabrata BSI for ≥48 h despite antifungal initiation). The impact of using fluconazole as initial antifungal treatment on the patients' prognosis was assessed by logistic regression analysis with the addition of a propensity score approach. A total of 94 patients with C. glabrata BSI were identified. Of these, 34 had received fluconazole and 35 had received an echinocandin/L-AmB-based regimen. Patients in the echinocandin/L-AmB group had poorer baseline clinical status than did those in the fluconazole group. Patients in the fluconazole group were more frequently (55.9% versus 28.6%) and much earlier (median time, 3 versus 7 days) switched to another antifungal regimen. Overall, 14-day mortality was 13% (9/69) and treatment failure 34.8% (24/69), with no significant differences between the groups. On multivariate analysis, after adjusting for baseline characteristics by propensity score, fluconazole use was not associated with an unfavorable evolution (adjusted odds ratio [OR] for 14-day mortality, 1.16, with 95% confidence interval [CI] of 0.22 to 6.17; adjusted OR for treatment failure, 0.83, with 95% CI of 0.27 to 2.61). In conclusion, initial fluconazole treatment was not associated with a poorer outcome than that obtained with echinocandins/L-AmB regimens in patients with C. glabrata BSI. (This study has been registered at ClinicalTrials.gov under registration no. NCT01236261.).


Asunto(s)
Antifúngicos/uso terapéutico , Candida glabrata/efectos de los fármacos , Candida glabrata/patogenicidad , Candidemia/tratamiento farmacológico , Anciano , Anfotericina B/farmacocinética , Anfotericina B/uso terapéutico , Antifúngicos/farmacocinética , Candidemia/sangre , Equinocandinas/uso terapéutico , Femenino , Fluconazol/farmacocinética , Fluconazol/uso terapéutico , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Estudios Prospectivos
4.
Artículo en Inglés | MEDLINE | ID: mdl-24594886

RESUMEN

This paper reports on both cathodoluminescence (CL) and blue thermoluminescence (TL) emission of well-characterized natural Spanish and Brazilian apatites [Ca5(PO4)3(OH, F, Cl)]. Chemical analyses performed by means of Electron Microprobe Analysis (EMPA) have shown the presence of trace elements that can induce CL bands. In this sense, the apatites shown emission bands peaked at 3.26, 2.86, 2.62, 2.14, 2.02 and 1.94eV are respectively linked to substitutional Ce(3+), Tb(3+), Dy(3+), Pr(3+), Sm(3+) and Mn(2+) in structural Ca(2+) positions. The 3.18eV emission band can be associated with intrinsic electron defects on oxygen of the phosphate group (PO4)(3-). The presence of (UO2)(2+) gives rise to an emission at 2.14eV. All the studied aliquots exhibit one single UV-blue TL peak that modifies the position from one sample to another (370, 256 and 268°C) probably due to (i) the variation in the crystallinity index (from 0.88 to 1.34) and (ii) successive chemical processes such as oxidation, dehydration, dehydroxylation, and fluorine ions losses due to the thermal readout.


Asunto(s)
Apatitas/química , Calcio/análisis , Elementos de la Serie de los Lantanoides/análisis , Luminiscencia , Mediciones Luminiscentes , Manganeso/análisis , Espectrometría Raman , Uranio/análisis , Difracción de Rayos X
5.
Rev. esp. quimioter ; 20(4): 375-386, sept. 2007. ilus, tab
Artículo en Español | IBECS | ID: ibc-74787

RESUMEN

La zigomicosis o mucormicosis es la tercera infección fúngica invasora tras la candidiasis y la aspergilosis. Tradicionalmente se ha consideradouna enfermedad de adquisición comunitaria, pero se está convirtiendo en una infección de frecuente adquisición nosocomial. En los últimosaños, numerosos estudios en instituciones aisladas apuntan a un aumento del número de casos de zigomicosis invasora a raíz de las nuevasterapias antifúngicas e inmunosupresoras, y al aumento de la población inmunodeprimida. Por otro lado, el diagnóstico de la zigomicosismuchas veces es complicado, sobre todo en las formas pulmonares y diseminadas. Uno de los principales problemas que presenta el aislamientode zigomicetos de muestras clínicas en el laboratorio de microbiología es que con frecuencia los resultados tienen una difícil interpretación.Además, el aumento del número de micosis invasoras por hongos resistentes a los antifúngicos ha llevado al desarrollo de nuevasmoléculas con actividad antifúngica y diferentes perfiles de actividad frente a los zigomicetos(AU)


Zygomycosis or mucormycosis is the third most invasive fungal infection after candidiasis and aspergillosis. Traditionally, it has been considereda community-acquired disease, but it is becoming a frequent nosocomial-acquired disease. Recently, several publications from differentinstitutions have reported an increase in the number of cases of invasive zygomycosis as a result of the new antifungal and immunosuppresivetherapies and the emerging immunocompromised population. In addition, the diagnosis of zygomycosis is elusive, mainly in pulmonaryand disseminated forms. One of the main limitations in isolating Zygomycetes from clinical samples is the interpretation of results. The increasingnumber of invasive fungal infections caused by multiresistant fungi has led to the development of new antifungal drugs with variableactivity against Zygomycetes(AU)


Asunto(s)
Humanos , Cigomicosis/epidemiología , Mucormicosis/epidemiología , Hongos/patogenicidad , Infección Hospitalaria/epidemiología , Cigomicosis/terapia , Mucormicosis/terapia , Antifúngicos/uso terapéutico , Factores de Riesgo , Quelantes del Hierro/uso terapéutico , Oxigenoterapia Hiperbárica
6.
Rev Esp Quimioter ; 20(4): 375-86, 2007 Dec.
Artículo en Español | MEDLINE | ID: mdl-18563211

RESUMEN

Zygomycosis or mucormycosis is the third most invasive fungal infection after candidiasis and aspergillosis. Traditionally, it has been considered a community-acquired disease, but it is becoming a frequent nosocomial-acquired disease. Recently, several publications from different institutions have reported an increase in the number of cases of invasive zygomycosis as a result of the new antifungal and immunosuppresive therapies and the emerging immunocompromised population. In addition, the diagnosis of zygomycosis is elusive, mainly in pulmonary and disseminated forms. One of the main limitations in isolating Zygomycetes from clinical samples is the interpretation of results. The increasing number of invasive fungal infections caused by multiresistant fungi has led to the development of new antifungal drugs with variable activity against Zygomycetes.


Asunto(s)
Hongos , Cigomicosis/terapia , Antifúngicos/uso terapéutico , Terapia Combinada/métodos , Hongos/aislamiento & purificación , Hongos/patogenicidad , Pruebas de Sensibilidad Microbiana , Factores de Riesgo , Cigomicosis/diagnóstico , Cigomicosis/epidemiología , Cigomicosis/etiología
7.
J Nutr ; 129(5): 1053-9, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10222399

RESUMEN

This study was conducted to determine whether the level of chromic oxide supplemented to diets containing gelatinized starch as the carbohydrate source affects digestibility, body composition, growth performances, and liver enzyme activities in gilthead sea bream, Sparus aurata. Gilthead sea bream fingerlings were fed diets containing gelatinized corn starch as the carbohydrate source and several levels of chromic oxide (0, 5, 10 and 20 g/kg) for 6 wk. No effect of dietary chromium level was detected on carbon, nitrogen, or dry matter digestibility. Calcium and phosphorus digestibility were higher in fish fed the diet supplemented with 5 g/kg chromic oxide than in fish fed the other supplemented diets. Dietary chromium did not affect dry matter, carbon, nitrogen, protein, or lipid concentrations in fish. However, fish fed 5 g/kg chromic oxide generally had higher levels of calcium, phosphorus, and ash than fish fed the other Cr-containing diets. Chromium concentration was significantly higher in fish fed the diets with 0.5 and 1% chromic oxide than in fish fed the control diet. Chromium supplementation of the diets did not affect the specific growth rate, the food efficiency ratio, the protein efficiency ratio, or, protein or nitrogen retention of the fish. Blood glucose and the activity of several liver enzymes involved in carbohydrate metabolism were unaffected by dietary chromic oxide. Alanine aminotransferase was lower in the fish fed the diet with 10 g/kg of chromic oxide than in unsupplemented controls. Our results indicate that chromic oxide can be used as a neutral marker in fish nutrition studies involving organic compounds, but not mineral salts.


Asunto(s)
Compuestos de Cromo/farmacología , Dieta , Minerales/metabolismo , Perciformes/metabolismo , Animales , Glucemia/metabolismo , Calcio/metabolismo , Carbono/metabolismo , Compuestos de Cromo/administración & dosificación , Carbohidratos de la Dieta/administración & dosificación , Carbohidratos de la Dieta/metabolismo , Digestión/efectos de los fármacos , Gelatina , Metabolismo de los Lípidos , Hígado/enzimología , Nitrógeno/metabolismo , Fósforo/metabolismo , Proteínas/metabolismo , Almidón/administración & dosificación , Zea mays
8.
Sangre (Barc) ; 41(1): 25-8, 1996 Feb.
Artículo en Español | MEDLINE | ID: mdl-8779030

RESUMEN

PURPOSE: Restrictive erythropoiesis caused by iron deficiency may hinder pre-deposit autotransfusion in surgical procedures. In order to evaluate the response to prophylactic ferrous ascorbate, a prospective study was conducted on patients subjected to orthopaedic surgery and autotransfusion. PATIENTS AND METHODS: Sixty-eight patients were included in the study: hip prostheses 67%, knee prostheses 25%, other procedures 7.4%. Their mean age was 61.3 +/- 10.2 years, and there were 42% male and 57% female. A mean of 2.8 +/- 0.6 units (450 mL) of blood were drawn to each patient in a month. Starting one week before their first blood donation and up to 2 months after surgery, each patient received 99 mg elementary iron per days as oral ferrous ascorbate. Blood cell counts were done at the beginning of the programme and after the first, second, third and fourth blood withdrawal, as well as one month after finishing the treatment. A survey of iron profile including serum iron, total iron binding capacity, transferrin saturation, serum ferritin and free erythrocyte protoporphyrin was carried out at onset and end of the programme in each patient. All data were analysed with the SPSS-PC 4.0 statistical programme. RESULTS: Haemoglobin rates decreased in every control, returning to values close to the initial ones by the end of the programme (mean figures are as follows: 14.63; 13.17; 12.70; 11.88; 14.11 g/dL); and similar changes were seen with respect to the other parameters of blood. The initial and final values for ferritin were 157.32 and 91.06 ng/mL, respectively, and no significant changes were appreciated in the other data from the iron profile, regardless of the number of blood units collected in a given case. Minor intolerance to ferrous ascorbate appeared in 11% of the patients. No significant differences with control patients were seen regarding hospitalization (16.54 vs 19.82 days) or postoperative fever (14.1% vs 17.11%). CONCLUSIONS: As opposed to others, we feel that iron treatment should be maintained up to 2 months after surgery since better results are thus attained. Recombinant erythropoietin is more expensive a method. Ferrous ascorbate is better tolerated than ferrous sulphate plus additives.


Asunto(s)
Anemia/prevención & control , Ácido Ascórbico/uso terapéutico , Transfusión de Sangre Autóloga , Prótesis de Cadera , Prótesis de la Rodilla , Anemia/etiología , Ácido Ascórbico/administración & dosificación , Transfusión de Sangre Autóloga/efectos adversos , Transfusión de Sangre Autóloga/estadística & datos numéricos , Recuento de Eritrocitos , Femenino , Ferritinas/sangre , Hematócrito , Humanos , Hierro/sangre , Masculino , Cuidados Preoperatorios , Estudios Prospectivos , Transferrina/análisis
9.
Antimicrob Agents Chemother ; 35(3): 442-7, 1991 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2039195

RESUMEN

The in vitro and in vivo antibacterial activities of a new tricyclic fluoroquinolone, E-4497 [S(-)-9-fluoro-3-methyl-10-(3-amine-3-methyl-azetidin-1-yl)-7-oxo- 2,3-dihydro- 7H-pyrido-(1,2,3-de)-1,4-benzoxazine-6-carboxylic acid], were evaluated in comparison with those of DR-3355 [S-(-)-ofloxacin], norfloxacin, and ciprofloxacin. E-4497 was more potent than norfloxacin and as potent as or more potent than DR-3355 and ciprofloxacin against Staphylococcus spp., Streptococcus spp., and Enterococcus faecalis. With the exception of Providencia spp., E-4497 inhibited 90% of the Enterobacteriaceae at less than or equal to 0.25 micrograms/ml. Against enteric bacteria, E-4497 was similar in potency to norfloxacin but less potent than DR-3355 and ciprofloxacin. For Pseudomonas aeruginosa, the MICs of E-4497, DR-3355, norfloxacin, and ciprofloxacin for 90% of strains were 2, 2, 4, and 0.5 micrograms/ml, respectively. Against Clostridium perfringens and Bacteroides fragilis, E-4497 (MICs for 90% of strains, 2 and 8 micrograms/ml, respectively) was two- to fourfold more active than norfloxacin and ciprofloxacin. E-4497 activity decreased moderately in the presence of 10 mM Mg2+. Urine at pH 5.5 caused a significant decrease in activity compared with urine at pH 7.2. However, the presence of serum either had no effect or increased the activity of E-4497. In general, E-4497 was bactericidal at the MIC. In systemic infections with Staphylococcus aureus, Streptococcus pyogenes, Escherichia coli, and Pseudomonas aeruginosa in mice, the protective effect of E-4497 was generally greater than that of norfloxacin and comparable to those of DR-3355 and ciprofloxacin.


Asunto(s)
Antiinfecciosos/farmacología , Bacterias/efectos de los fármacos , Infecciones Bacterianas/tratamiento farmacológico , Fluoroquinolonas , Quinolonas , Animales , Ciprofloxacina/farmacología , Evaluación Preclínica de Medicamentos , Interacciones Farmacológicas , Magnesio/farmacología , Masculino , Ratones , Pruebas de Sensibilidad Microbiana , Norfloxacino/farmacología , Ofloxacino/farmacología
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