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1.
Environ Sci Pollut Res Int ; 30(56): 118536-118544, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37917255

RESUMO

Ketorolac, a highly persistent NSAID of environmental concern, was significantly removed from water (80% removal) through photoelectrocatalysis where titanium dioxide nanotubes prepared by Ti foil electrochemical anodization at 30 V were used as photoanodes. Fifteen milligrams per liter of ketorolac solutions in a 0.05 M Na2SO4 aqueous medium was subjected to irradiation from a 365-nm light with an intensity of 1 mWcm-2 and under an applied potential of 1.3 V (vs. Hg/Hg2SO4/sat.K2SO4) at pH 6.0. When each process (photo and electrocatalysis) was carried out separately, less than 20% drug removal was achieved as monitored through UV-vis spectrophotometry. Through scavenging experiments, direct oxidation on the photogenerated holes and oxidation by hydroxyl radical formation were found to play a key role on ketorolac's degradation. Chemical oxygen demand (COD) analyses also showed a significant COD decreased (68%) since the initial COD value was 31.3 mg O2/L and the final COD value was 10.1 mg O2/L. A 48% mineralization was also achieved, as shown by total organic carbon (TOC) analyses. These results showed that electrodes based on titania nanotubes are a promising alternative material for simultaneous photocatalytic and electrocatalytic processes in water remediation.


Assuntos
Mercúrio , Nanotubos , Poluentes Químicos da Água , Água , Cetorolaco , Titânio , Oxirredução , Eletrodos , Catálise
2.
RSC Adv ; 11(12): 6509-6516, 2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-35423200

RESUMO

Graphene oxide (GO) has lately become an interesting biomaterial due to its stunning properties and versatility, its claimed antimicrobial activity holds promise for potential health applications. Nonetheless, multiple reports investigating GO antibacterial activity lack rigor and uniformity on several aspects which are crucial when evaluating this effect. In this work, we highlight and address these parameters: morphology of the materials, exposure time, exposure methodology and concentration. We investigate the effect of GO and GO-based metallic composites observing these parameters on two pathogenic bacteria. Our nanomaterials have been characterized by means of SEM, EDX, DLS, FTIR and Raman spectroscopies. Escherichia coli and Salmonella Typhimurium suspended in saline solutions (no growth medium) have been exposed to GO (lateral size = 100 nm), silver nanoparticles, ceria nanoparticles, GO/silver and GO/ceria aqueous solutions for 0, 5, 15, 30, 60 and 90 minutes, before plating. Our experiments indicate that no prior exposure of the materials to bacteria (0 min) results in poor inactivation rates independently of concentration, while increasing times of interaction enhance inactivation. Moreover, our experiments show concentration-dependent results showing higher activity for concentrations of 100 µg mL-1; and prove that 30 minutes of exposure are sufficient to deploy the antimicrobial effects of these materials. GO possesses the lowest inactivation rate, and the presence of silver and ceria nanoparticles in the GO surface boosts its antimicrobial effect. Thus, the enhancement of the antibacterial activity of graphene oxide relies on 30 minutes of interaction in water, concentration of 100 µg mL-1, and its decoration by silver/ceria nanoparticles.

3.
BMC Cardiovasc Disord ; 17(1): 100, 2017 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-28410571

RESUMO

BACKGROUND: The inflammatory process in aortic valvular stenosis persists after surgery to replace the valve in almost half of the patients. No association has been found to its persistence. The main objective of this study was to evaluate the inflammatory response in patients with aortic stenosis through the determination of several biomarkers in plasma measured before and after the valvular replacement and to seek an association with the type of prosthesis used. METHODS: This is an observational study with a follow up of 6 months in subjects with severe aortic stenosis. Seric concentrations of TNFa, IL-1, IL-6 and ICAM and echocardiographic variables were quantified previous to the surgery and a week and 6 months after it. A group of control subjects paired by age and gender was included. RESULTS: Seventy-nine subjects were studied of which 57% were male; the average age was of 59 (± 11.4) years. Previous to surgery, the concentration of cytokines was higher in patients than in control subjects. A biological prosthesis was implanted in 48 patients and a mechanical prosthesis in 31. Both, types of prosthesis have components made of titanium. The echocardiograms 1 week and 6 months after the surgery showed a decrease in the mean aortic gradient and an increase in the valvular area (p = 0.001). Half of the patients still showed high proinflammatory cytokine levels. There were no differences according to the type of prosthesis implanted after adjustments for demographic variables, comorbidities and echocardiographic data. CONCLUSIONS: The inflammatory response caused by both types of valvular prothesis at 6 months after implantation were similar. Both types of prosthesis are recommended, they had similarities in hemodynamic profiles registered with Doppler echocardiography. Age of the patient or the suitability use of anticoagulants determines the type of prosthesis to be used.


Assuntos
Estenose da Valva Aórtica/cirurgia , Biomarcadores/sangue , Bioprótese , Próteses Valvulares Cardíacas , Inflamação/sangue , Estenose da Valva Aórtica/sangue , Ecocardiografia Doppler , Feminino , Seguimentos , Humanos , Inflamação/etiologia , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Período Pré-Operatório , Estudos Prospectivos , Desenho de Prótese , Fatores de Tempo
4.
MEDISUR ; 15(2)2017. ilus, tab
Artigo em Espanhol | CUMED | ID: cum-68174

RESUMO

La modernidad se percibió en Cuba en las grandes y medianas ciudades hacia finales de la década del 70 del siglo XIX, extendiéndose hasta 1930 aproximadamente; trajo consigo cambios económicos y sociales. movilidad urbana, tráfico de noticias, desarrollo tecnológico, todo era sinónimo de modernidad. Cienfuegos por estos años tenía su economía totalmente consolidada, en lo que influyó el poderoso desenvolvimiento económico del mundo moderno. La odontología cienfueguera no se quedó al margen de lo que estaba sucediendo y cobró esplendor con la llegada de especialistas de reconocido prestigio. El trabajo ofrece un panorama histórico de esta profesión en Cienfuegos, destacando el desarrollo del arte dental en el contexto de la modernidad. Se exponen los servicios y aportes de los profesionales de esta rama en esa etapa, con énfasis en la personalidad de Serafina C. Daumy Martínez, odontóloga cubana considerada la primera mujer graduada de cirugía dental en Cuba(AU)


Modernity was perceived in Cuba in large and medium-sized cities by the end of the 1970s, extending to about 1930; it brought economic and social changes. Urban mobility, news traffic, technological development, was all synonym of Modernity. By these years Cienfuegos had a totally consolidated economy influenced by powerful economic development of the Modern World. The Cienfuegos Dentistry was not alien to this process and gained splendor with the arrival of specialists of recognized prestige. This paper offers a historical panorama of this profession in Cienfuegos, highlighting the dental art development in the context of Modernity. Services and contributions by the professionals of this branch in this period are presented. With emphasis on the personality of Serafina C. Daumy Martínez, Cuban odontologist considered to be the first woman graduated in Dental Surgery in Cuba(AU)


Assuntos
Humanos , Feminino , História da Odontologia , Cuba
5.
J Water Health ; 10(1): 20-30, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22361699

RESUMO

Sequential helminth egg inactivation using a solar driven advanced oxidation process (AOP) followed by chlorine was achieved. The photo-assisted Fenton process was tested alone under different H(2)O(2) and/or Fe(II) concentrations to assess its ability to inactivate Ascaris suum eggs. The effect of free chlorine alone was also tested. The lowest egg inactivation results were found using Fe(II) or H(2)O(2) separately (5 and 140 mmol L(-1), respectively) in dark conditions, which showed about 28% inactivation of helminth eggs. By combining Fe(II) and H(2)O(2) at the same concentrations described earlier, 55% of helminth egg inactivation was achieved. By increasing the reagent's concentration two-fold, 83% egg inactivation was achieved after 120 min of reaction time. Process efficiency was enhanced by solar excitation. Using solar disinfection only, the A. suum eggs inactivation reached was the lowest observed (58% egg inactivation after 120 min (120 kJ L(-1))), compared with tests using the photo-Fenton process. The use of the photo-Fenton reaction enhanced the process up to over 99% of egg inactivation after 120 kJ L(-1) when the highest Fe(II) and H(2)O(2) concentration was tested. Practically no effect on the helminth eggs was observed with free chlorine alone after 550 mg min L(-1) was used. Egg inactivation in the range of 25-30% was obtained for sequential processes (AOP then chlorine) using about 150 mg min L(-1).


Assuntos
Ascaris/efeitos dos fármacos , Ascaris/efeitos da radiação , Cloro/farmacologia , Peróxido de Hidrogênio/farmacologia , Ferro/farmacologia , Oocistos/efeitos dos fármacos , Oocistos/efeitos da radiação , Luz Solar , Purificação da Água/métodos , Animais , México , Oxirredução/efeitos dos fármacos , Oxirredução/efeitos da radiação , Contagem de Ovos de Parasitas
6.
Appl Environ Microbiol ; 77(19): 6746-54, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21821751

RESUMO

The first ∼10% of spores released from sporangia (early spores) during Bacillus subtilis sporulation were isolated, and their properties were compared to those of the total spores produced from the same culture. The early spores had significantly lower resistance to wet heat and hypochlorite than the total spores but identical resistance to dry heat and UV radiation. Early and total spores also had the same levels of core water, dipicolinic acid, and Ca and germinated similarly with several nutrient germinants. The wet heat resistance of the early spores could be increased to that of total spores if early spores were incubated in conditioned sporulation medium for ∼24 h at 37°C (maturation), and some hypochlorite resistance was also restored. The maturation of early spores took place in pH 8 buffer with Ca(2+) but was blocked by EDTA; maturation was also seen with early spores of strains lacking the CotE protein or the coat-associated transglutaminase, both of which are needed for normal coat structure. Nonetheless, it appears to be most likely that it is changes in coat structure that are responsible for the increased resistance to wet heat and hypochlorite upon early spore maturation.


Assuntos
Bacillus subtilis/fisiologia , Viabilidade Microbiana/efeitos da radiação , Esporos Bacterianos/fisiologia , Estresse Fisiológico , Bacillus subtilis/química , Bacillus subtilis/efeitos dos fármacos , Bacillus subtilis/efeitos da radiação , Cálcio/análise , Temperatura Alta , Ácido Hipocloroso/toxicidade , Ácidos Picolínicos/análise , Esporos Bacterianos/química , Esporos Bacterianos/efeitos dos fármacos , Esporos Bacterianos/efeitos da radiação , Raios Ultravioleta , Água/análise
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