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1.
Sci Total Environ ; 642: 842-853, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30045524

RESUMO

In this work, the presence of 20 pharmaceuticals in wastewater from Colombia is investigated. Several widely consumed compounds have been detected in wastewater samples from different origins and geographical areas in Colombia. The studied pharmaceuticals included antibiotics, analgesics and anti-inflammatories, cholesterol lowering statin drugs, lipid regulators, and anti-depressants. The investigated samples were urban wastewater collected during one whole week before (influent) and after treatment (effluent) in the wastewater treatment plants (WWTPs) of Bogotá and Medellin. Raw wastewater from the Hospital of Tumaco and from the city of Florencia were also collected. Analyses performed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) revealed that most of the target analytes were present in all the wastewater samples. The highest concentrations (up to 50 µg/L) corresponded to acetaminophen, but several antibiotics, such as azithromycin, ciprofloxacin and norfloxacin, and antihypertensive drugs, such as losartan and valsartan, were commonly present in influent wastewater (IWW) at levels above 1 µg/L. Moreover, the treatment applied in WWTPs seemed to not efficiently remove the compounds under study, because most pharmaceuticals were also present in effluent wastewater (EWW) at concentrations close to those of the IWW. Special emphasis was made in this work on the quality of data reported, performing a detailed study of quality control (QC) samples. The analytical approach used -direct injection of 5-fold diluted samples without any additional treatment - is simpler and faster than the commonly applied solid phase extraction (SPE). The use of 12 isotope-labelled internal standards ensured the satisfactory correction of matrix effects for the corresponding analytes. For the remaining 8 compounds, no drastic matrix effects were observed, and only four compounds (cloxacillin, doxycycline, losartan, tetracycline) presented QC recoveries near or slightly below 60%, revealing ionization suppression, particularly in the IWW. Data on the occurrence of pharmaceuticals reported in this paper are the basis for current studies that aim to develop efficient systems for the degradation/removal of these compounds from the aquatic environment.


Assuntos
Preparações Farmacêuticas/análise , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Poluentes Químicos da Água/análise , Cromatografia Líquida de Alta Pressão , Cidades , Colômbia , Monitoramento Ambiental , Extração em Fase Sólida , Espectrometria de Massas em Tandem
2.
Dalton Trans ; 46(17): 5680-5688, 2017 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-28220915

RESUMO

While bimetallic azacryptands are known to selectively coordinate CO2, there is little knowledge on how different substitution patterns of the azacryptand cage structure influence CO2 coordination. Stopped-flow UV-vis spectroscopy, electrochemical analysis and DFT calculations were performed on a series of dinickel azacryptands and showed different rates of CO2 coordination to the complexes. We herein present data showing that the different flexibility of the azacryptands is directly responsible for the difference in the CO2 uptake capability of dinickel azacryptand complexes.

3.
Anal Chim Acta ; 706(2): 275-84, 2011 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-22023862

RESUMO

Molecularly imprinted polymers (MIPs) are currently used to provide selectivity in chemical sensors. In this context, a non-covalent bisphenol-A (BPA)-imprinted polymer using 4-vinylpyridine (4-Vpy) as the functional monomer, ethylene glycol dimethacrylate (EGDMA) as crosslinker and a low volatile solvent, triethylene glycol dimethyl ether (TRIGLYME), in combination with a non-reactive linear polymer, poly (vinyl acetate) (PVAc), as porogen, was synthesized with a simple polymerization procedure. Batch rebinding experiments were carried out to evaluate the binding and selectivity properties of the BPA-MIP. The experimental adsorption isotherms were fitted and a heterogeneous distribution of the binding sites was found. The selectivity of MIP demonstrated higher affinity for target BPA and BPA-analogues over other common water pollutants. The adsorption kinetics followed the pseudo-second-order kinetic model so that the specific adsorption in the imprinted cavities by two strong hydrogen bonds could be described as a chemisorption process. The diffusion mechanism was determined by the intra-particle diffusion and Boyd models, both of them revealing that the adsorption was mainly governed by intra-particle diffusion. MIP was shown to be promising for regeneration without significant loss in adsorption capacity.

4.
Talanta ; 85(4): 2080-8, 2011 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-21872061

RESUMO

Capacity to migrate of a representative group of polymeric additives, dyes, antioxidants, hindered amine light stabilizers (HALS) or antistatics, from plastic toys to saliva was analyzed to protect children in their habits of sucking and biting. Most of target additives appear no-regulated in toys normative but adverse effects on human health of some of them have been demonstrated and their presence in others commercial articles normative has been included. In order to offer an effective and easy tool to perform these controls, migration tests by dynamic and static contact, followed by a preconcentration step by liquid-liquid extraction (LLE) and ultra performance liquid chromatographic analysis with ultraviolet-visible and evaporative light scattering detections (UPLC-UV/Vis-ELSD) have been optimized to evaluate the migrated amounts of the additives in saliva simulant. The detection limits of the migration methodologies were ranged from 8.68 × 10(-2) to 1.30 × 10(-3)mg migrated (L simulant)(-1). Influence of several variables on this mass transport, as time, temperature and friction, was also analyzed to achieve the most aggressive methodology to protect consumers. Migration of several studied additives, whose presence has been demonstrated in several purchased commercial toys, has been observed.


Assuntos
Testes de Química Clínica/métodos , Movimento (Física) , Jogos e Brinquedos , Polímeros/análise , Saliva/química , Fricção , Humanos , Polímeros/química , Polímeros/isolamento & purificação , Polímeros/toxicidade , Temperatura , Fatores de Tempo
5.
J Chromatogr A ; 1179(2): 152-60, 2008 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-18093605

RESUMO

Two high-performance liquid chromatographic methods, with ultraviolet-visible spectrophotometry detection (HPLC-UV/Vis) and with tandem mass spectrometry triple quadrupole interfaced with positive ion mode electrospray ionization detection (HPLC-ESI+-QqQ-MS/MS), for determination and quantification of ten commercial dyes are proposed for control in commercial products. Multiple peaks observed for some of the studied dyes in HPLC-UV/Vis chromatograms forced to obtain structural information by HPLC-ESI-MS/MS method with scan mode. The quality parameters of the two proposed chromatographic methods were evaluated for different requirements of normative, showing detection (LODs) and quantification (LOQs) limits around 60-890 and 200-2990 microg L(-1) for HPLC-UV/Vis, and 4.54-14.3 and 15.0-47.6 microg L(-1) for HPLC-ESI+-QqQ-MS/MS.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Corantes/análise , Manufaturas/análise , Corantes/toxicidade , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrofotometria Ultravioleta , Espectrometria de Massas em Tandem
6.
Mol Plant Microbe Interact ; 17(3): 254-62, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15000392

RESUMO

The hrp pathogenicity island of Pseudomonas syringae encodes a type III secretion system (TTSS) that translocates effectors into plant cells. Most genes encoding effectors are dispersed in the P. syringae genome. Regardless of location, all are regulated coordinately by the alternative sigma factor HrpL. An HrpL-dependent promoter-trap assay was developed to screen genomic libraries of P. syringae strains for promoters whose activity in Escherichia coli is dependent on an inducible hrpL construct. Twenty-two HrpL-dependent promoter fragments were isolated from P. syringae Psy61 that included promoters for known HrpL-dependent genes. One fragment also was isolated that shared no similarity with known genes but retained a near consensus HrpL-dependent promoter. The sequence of the region revealed a 375-amino acid open reading frame encoding a 40.5-kDa product that was designated HopPsyL. HopPsyL was structurally similar to other secreted effectors and carried a putative chloroplast-targeting signal and two predicted transmembrane domains. HopPsyL':'AvrRpt2 fusions were translocated into host cells via the P. syringae pv. tomato DC3000 hrp TTSS. A hopPsyL::kan mutant of Psy61 exhibited strongly reduced virulence in Phaseolus vulgaris cv. Kentucky Wonder, but did not appear to act as a defense response suppressor. The ectopically expressed gene reduced the virulence of Pseudomonas syringae DC3000 transformants in Arabidopsis thaliana Col-0. The gene was shown to be conserved in 6 of 10 P. syringae pv. syringae strains but was not detected in 35 strains of other pathovars. HopPsyL appears to be a novel TTSS-dependent effector that functions as a host-species-specific virulence factor in Psy61.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Ligação a DNA/genética , Genoma Bacteriano , Proteínas de Membrana/genética , Pseudomonas syringae/genética , Fator sigma/genética , Arabidopsis/microbiologia , Proteínas de Bactérias/metabolismo , Transporte Biológico , Proteínas de Ligação a DNA/metabolismo , Regulação Bacteriana da Expressão Gênica , Proteínas de Membrana/metabolismo , Dados de Sequência Molecular , Mutação , Fases de Leitura Aberta/genética , Phaseolus/microbiologia , Regiões Promotoras Genéticas/genética , Pseudomonas syringae/metabolismo , Pseudomonas syringae/patogenicidade , Fator sigma/metabolismo , Virulência
8.
Rev Iberoam Micol ; 16(S): S26-30, 1999 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-18473601

RESUMO

We revised the most important antifungal drugs used in cutaneous mycosis. We emphasize in pharmacokinetics, drug adverse reactions and its management in the different types of pathology.

10.
Santiago; DIGEDER; 1997. 26 p.
Monografia em Espanhol | LILACS, MINSALCHILE | ID: lil-388010
12.
Santiago; DIGEDER; 1996. 22 p.
Monografia em Espanhol | LILACS, MINSALCHILE | ID: lil-388007
14.
CM publ. méd ; 8(1): 15-21, ago. 1995. tab
Artigo em Espanhol | LILACS | ID: lil-154592

RESUMO

El objetivo de este trabajo fue determinar la prevalencia de bocio en escolares de la ciudad de Mar del Plata. Se seleccionó una muestra entre alumnos de 6 a 14 años de edad de escuelas urbanas y periurbanas de la ciudad de Mar del Plata; la muestra se realizó por conglomerados y posteriormente por métodos aleatorios. Se encuestaron 889 alumnos, 54,1 por ciento de sexo masculino y 45,9 por ciento del femenino, y se recolectó orina en un 8,7 por ciento de los varones. Se detectó un 17,2 por ciento del nivel Ia, 1,7 por ciento Ib y 0,1 por ciento II Total = 19 por ciento (según clasificación OPS). No se observaron diferencias significativas respecto al sexo y edad, ni a la provisión de agua corriente y/o de pozo ni a residencia urbana o rural. Si se observó diferencia significativa entre escuelas Estatales y Privadas : 21,2 por ciento y 11,6 por ciento respectivamente. Dado las diferencias observadas entre los distintos equipos de trabajo (todos los profesionales intervinientes con experiencia en palpación de tiroides), se resolvió efectuar ecografía a un 20 por ciento de los positivos más un 10 por ciento de normales : los resultados de las ecografías avalan ampliamente los hallazgos palpatorios. De las 53 muestras de orina procesadas, se observó un promedio de 21,1 mcg/dl de iodo con un desvío standar de 6,7 mcg/dl (es decir, iodurias altamente satisfactorias). Se ha decidido profundizar la investigación, determinando anticuerpos TPO y medición TSH, para destacar tiroiditis crónica e hipotiroidismo subclínico


Assuntos
Humanos , Criança , Adolescente , Bócio Endêmico/epidemiologia , Serviços de Saúde Escolar , Argentina/epidemiologia , Estudos Transversais , Prevalência
15.
CM publ. méd ; 8(1): 15-21, ago. 1995. tab
Artigo em Espanhol | BINACIS | ID: bin-23546

RESUMO

El objetivo de este trabajo fue determinar la prevalencia de bocio en escolares de la ciudad de Mar del Plata. Se seleccionó una muestra entre alumnos de 6 a 14 años de edad de escuelas urbanas y periurbanas de la ciudad de Mar del Plata; la muestra se realizó por conglomerados y posteriormente por métodos aleatorios. Se encuestaron 889 alumnos, 54,1 por ciento de sexo masculino y 45,9 por ciento del femenino, y se recolectó orina en un 8,7 por ciento de los varones. Se detectó un 17,2 por ciento del nivel Ia, 1,7 por ciento Ib y 0,1 por ciento II Total = 19 por ciento (según clasificación OPS). No se observaron diferencias significativas respecto al sexo y edad, ni a la provisión de agua corriente y/o de pozo ni a residencia urbana o rural. Si se observó diferencia significativa entre escuelas Estatales y Privadas : 21,2 por ciento y 11,6 por ciento respectivamente. Dado las diferencias observadas entre los distintos equipos de trabajo (todos los profesionales intervinientes con experiencia en palpación de tiroides), se resolvió efectuar ecografía a un 20 por ciento de los positivos más un 10 por ciento de normales : los resultados de las ecografías avalan ampliamente los hallazgos palpatorios. De las 53 muestras de orina procesadas, se observó un promedio de 21,1 mcg/dl de iodo con un desvío standar de 6,7 mcg/dl (es decir, iodurias altamente satisfactorias). Se ha decidido profundizar la investigación, determinando anticuerpos TPO y medición TSH, para destacar tiroiditis crónica e hipotiroidismo subclínico


Assuntos
Humanos , Criança , Adolescente , Bócio Endêmico/epidemiologia , Estudos Transversais , Argentina/epidemiologia , Prevalência
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