Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
1.
Molecules ; 27(21)2022 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-36364408

RESUMEN

There is increasing scientific evidence that some pharmaceuticals are present in the marine ecosystems at concentrations that may cause adverse effects on the organisms that inhabit them. At present, there is still very little scientific literature on the (bio)accumulation of these compounds in different species, let alone on the relationship between the presence of these compounds and the adverse effects they produce. However, attempts have been made to optimize and validate analytical methods for the determination of residues of pharmaceuticals in marine biota by studying the stages of sample treatment, sample clean-up and subsequent analysis. The proposed bibliographic review includes a summary of the most commonly techniques, and its analytical features, proposed to determine pharmaceutical compounds in aquatic organisms at different levels of the trophic chain in the last 10 years.


Asunto(s)
Organismos Acuáticos , Contaminantes Químicos del Agua , Monitoreo del Ambiente/métodos , Contaminantes Químicos del Agua/análisis , Ecosistema , Preparaciones Farmacéuticas
2.
Plant Dis ; 2020 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-32762322

RESUMEN

In Chile, the 2019-2020 sweet cherry season yielded 228,548 t, produced on 38,392 hectares and an average annual crop value about US$1.6 billion (http://www.iqonsulting.com/yb/). Between autumn 2019 and summer of 2020, branch and limbs dieback symptoms were observed in two 12-year-old sweet cherry (Prunus avium L.) orchards located in the O'Higgins region (Chile Central Valley). Furthermore, other symptoms such as wilting leaves, cankers, bark cracking, emission of gum exudates and internal wood necrosis were detected on trees of "Bing", "Santina" and "Sweetheart" cultivars (Cainelli et al. 2017). Wood fragments from symptomatic branches were surface sterilized with 95% ethanol, flaming and placed onto potato dextrose agar (PDA) amended with 0.5 g liter-1 of streptomycin sulfate (Berbegal et al. 2014). After 7 days of incubation at 25°C, pink to red colonies with white margins were isolated. Each isolate was characterized by having hyaline and oblong-ellipsoidal conidia of 5.76 ± 0.88 × 1.76 ± 0.36 µm (n=100) (Trouillas et al. 2012). According to these morphological features, the fungus was identified as Calosphaeria pulchella (Pers.: Fr.) J. Schröt (anamorph Calosphaeriosphora pulchella Réblová,L. Mostert, W. Gams & Crous) (Réblová et al. 2004). ITS (Internal Transcribed Spacer region of the rDNA) sequence comparison using BLAST analysis revealed a 99.48% identity and 100% query coverage between C. pulchella sequence HM237297 and the Chilean isolates. Moreover, the Chilean isolates were confirmed by means of phylogenetic analysis using ITS sequences of C. pulchella available in GenBank database. The maximum-parsimony phylogenetic tree supported the cluster analysis of the Chilean C. pulchella isolates with those obtained in other regions of the world with a bootstrap value of 95% (Berbegal et al. 2014; Trouillas et al. 2012). The Chilean ITS sequences were deposited into GenBank (MT378444 to MT378447). Two-year-old sweet cherry trees cv. Bing were inoculated with the Chilean isolates. Six trees were used as replicates. To accomplish this goal, two punctures of 5mm diameter were made in two branches per tree with a cork borer and a plug of mycelium from 7-day-old colonies was laid on the wound mycelium side down. Six trees were inoculated with sterile agar plugs. Every puncture was sealed with petroleum jelly and wrapped with parafilm. Four months after inoculation, the vascular streaking developing from the inoculated wounds was measured. The average lesion lengths on inoculated and non-inoculated shoots were 43.79 and 21.79 mm, respectively, which were significantly different according LSD Fisher test (p<0.05). C. pulchella was recovered from all the inoculated branches. No fungus was isolated from the controls, confirming Koch's postulates (Trouillas et al. 2012). To our knowledge this is the first report of C. pulchella causing canker and branch dieback in sweet cherry trees in Chile. This new disease represents a serious threat to the Chilean cherry industry, and further research on disease control is needed.

3.
J Hazard Mater ; 479: 135586, 2024 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-39191017

RESUMEN

Antibiotics are among the emerging contaminants of greatest concern to the scientific community. However, the occurrence and behaviour of their metabolites in soils have been scarcely studied. To address this research gap, this study investigates the occurrence, sorption, dissipation kinetics, and environmental risk of highly important antibiotics (sulfamethazine, sulfadiazine, sulfamethoxazole, trimethoprim) and their main metabolites in Mediterranean agricultural soils. Batch experiments were conducted under natural conditions for 120 days. Five different dissipation kinetics models were applied to elucidate antibiotics degradation. The sorption isotherms were evaluated by three different models. Most of the antibiotics and metabolites tested showed a good fit with the Linear Isotherm model (R2 >0.96) and biphasic dissipation kinetic models (R2 >0.90). The dissipation and the endpoints values (DT50 and DT90) depended on the soil type properties. A Lixisol soil demonstrated reduced degradation of the investigated compounds. Trimethoprim showed the highest persistence, followed by sulfamethazine, sulfamethoxazole, and sulfadiazine. Parent compounds exhibited lower degradation rates than their metabolites. Remaining antibiotic concentrations were found to be below the predicted no-effect concentration in soil, suggesting that they may not pose a risk to terrestrial biota. This study provides valuable insights into the behaviour of these antibiotics and their metabolites in soil.


Asunto(s)
Agricultura , Antibacterianos , Contaminantes del Suelo , Contaminantes del Suelo/análisis , Contaminantes del Suelo/química , Contaminantes del Suelo/metabolismo , Antibacterianos/química , Antibacterianos/análisis , Cinética , Medición de Riesgo , Suelo/química , Monitoreo del Ambiente
4.
Antibiotics (Basel) ; 13(5)2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38786137

RESUMEN

Microplastics (MPs) and antibiotics are emerging pollutants widely found in aquatic environments, potentially causing environmental harm. MPs may act as carriers for antibiotics, affecting their environmental distribution. This study investigates the adsorption of four macrolide antibiotics and a metabolite onto two types of MPs: polyethylene terephthalate (PET) and polyethylene (PE). Results revealed a linear isotherm adsorption model, with higher adsorption to PET than to PE (R2 > 0.936 for PE and R2 > 0.910 for PET). Hydrophobic interactions and hydrogen bonding could be the main adsorption mechanisms, with pore filling potentially involved. Reduced particle size enhances adsorption due to the increase of active adsorption sites. This increasement is more pronounced in PE than in PET, leading to an 11.6% increase in the average adsorption of all macrolides to PE, compared to only 5.1% to PET. Dissolved organic matter inhibits adsorption (azithromycin adsorption to PE was reduced from 12% to 5.1%), while salinity enhances it just until 1% salinity. pH slightly influences adsorption, with maximal adsorption at neutral pH. Results in real samples showed that complexity of the matrix decreased adsorption. Overall, these findings indicate that PE and PET MPs can be a vector of macrolides in aquatic environments.

5.
Environ Pollut ; 349: 123919, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38582188

RESUMEN

Microplastic (MP) contamination is in the spotlight today, yet knowledge of their interaction with other organic contaminants in the soil environment is limited. Concerns extend to endocrine disrupting chemicals (EDCs), known for their potential to interfere with the hormonal systems of organisms and for their persistence and widespread presence in the environment. In this study, the most frequently occurring EDCs were monitored both in alluvial soil and in soil contaminated with different MPs commonly found in soil media, polyethylene, polyamide, and polystyrene. Bisphenol A and parabens were the most rapidly dissipating compounds, followed by triclosan and triclocarban, with the latter showing poor degradation. Per- and polyfluoroalkyl substances (PFAS) showed high persistence as concentrations remained nearly constant throughout the experiment. Although they fitted well with first-order dissipation kinetics, most showed biphasic behavior. The co-occurrence of MPs in the soil influenced the kinetic behavior in most cases although the differences were not very marked. MPs could impact sorption-desorption processes, affecting contaminant mobility and bioavailability to organisms in soil. These findings strengthen evidence for the influence of MPs on the behavior of soil contaminants such as EDCs, not only as vectors or sources of contaminants but by affecting dissipation kinetics.


Asunto(s)
Compuestos de Bencidrilo , Disruptores Endocrinos , Monitoreo del Ambiente , Microplásticos , Contaminantes del Suelo , Suelo , Contaminantes del Suelo/análisis , Disruptores Endocrinos/análisis , Microplásticos/análisis , Suelo/química , Compuestos de Bencidrilo/análisis , Triclosán/análisis , Fenoles/análisis , Parabenos/análisis , Carbanilidas/análisis
6.
J Chromatogr A ; 1701: 464064, 2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37201430

RESUMEN

Due to the growing trend of organic food, there is still concern over the use of chemicals and pesticides in agriculture. In recent years, several procedures have been validated for the control of pesticides in food. In the present research, a comprehensive two-dimensional liquid chromatography coupled with tandem mass spectrometry is proposed for the first time for a multi-class analysis of 112 pesticides in corn-based products. Notably, a "reduced" QuEChERS-based method as extraction and clean-up procedure prior to the analysis, was successfully employed. Limits of quantification values were lower than the ones fixed by the European legislation; intra-day and inter-day precision were lower than 12.9% and 15.1%, respectively (at the 500 µg/kg concentration levels). Over 70% of the analytes provided recoveries between 70% and 120% range (at 50, 500 and 1000 µg/kg concentration levels) with standard deviation values below 20%. In addition, matrix effect values were in the range between 13% to 161%. The method was applied to the analysis of real samples, and three pesticides were detected at trace levels in both samples. The findings of this work pave the way for the treatment of complex matrices such as corn products.


Asunto(s)
Residuos de Plaguicidas , Plaguicidas , Plaguicidas/análisis , Espectrometría de Masas en Tándem/métodos , Zea mays , Cromatografía Liquida/métodos , Agricultura , Residuos de Plaguicidas/análisis
7.
Talanta ; 262: 124687, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37229817

RESUMEN

Antibiotics are a group of drugs used for the treatment of bacterial diseases. They are used in both human and veterinary medicine and, although they are not permitted, they are sometimes used as growth promoters. The present research compares two extraction techniques: ultrasound-assisted extraction (UAE) and microwave-assisted extraction (MAE) in order to evaluate their efficiency in the determination of 17 usually prescribed antibiotics in human nails. The extraction parameters were optimized using multivariate techniques. Once both techniques were compared, MAE was selected as optimal due to its greater experimental practicability together with the better extraction efficiencies it provides. Target analytes were detected and quantified by ultra-high performance liquid chromatography with tandem mass spectrometry detection (UHPLC-MS/MS). The run time was 20 min. The methodology was then successfully validated, obtaining acceptable analytical parameters according to the guide used. Limits of detection were between 0.3 and 3 ng g-1 and limits of quantification were in the range from 1.0 to 4.0 ng g-1. Recovery percentages ranged from 87.5% to 114.2%, and precision (in terms of standard deviation) was less than 15% in all cases. Finally, the optimized method was applied to nails taken from 10 volunteers and the results revealed the presence of one or more antibiotics in all the samples examined. The most commonly found antibiotic was sulfamethoxazole, followed by danofloxacin and levofloxacin. The results demonstrated, on the one hand, the presence of these compounds in the human body and, on the other hand, the suitability of nails as a non-invasive biomarker of exposure.


Asunto(s)
Antibacterianos , Espectrometría de Masas en Tándem , Humanos , Antibacterianos/análisis , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida de Alta Presión/métodos , Uñas/química , Extracción en Fase Sólida/métodos
8.
Pediatr Infect Dis J ; 42(12): e473-e475, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37670468

RESUMEN

We analyzed the frequency, clinical impact and severity of respiratory syncytial virus (RSV) and SARS-CoV-2 coinfections in a single pediatric center between March 2020 and January 2023. Compared to single RSV infections, RSV/SARS-CoV-2 coinfections were uncommon (2.1%), occurred more frequently during circulation of omicron, and were associated with increased disease severity as defined by longer hospitalization and increased need for high-flow nasal cannula.


Asunto(s)
COVID-19 , Coinfección , Infecciones por Virus Sincitial Respiratorio , Virus Sincitial Respiratorio Humano , Lactante , Niño , Humanos , Preescolar , SARS-CoV-2 , Relevancia Clínica , COVID-19/epidemiología , COVID-19/complicaciones , Hospitalización
9.
Talanta ; 234: 122642, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34364451

RESUMEN

Personal care products (PCPs) and cosmetics are indispensable product in our daily routine. Their widespread use makes them a potential route of exposure for certain contaminants to which human would not be normally exposed. One of these contaminants includes endocrine disrupting chemicals, molecules capable of mimicking the body's natural hormones and interfering with the endocrine system. Some of them are ingredients included in the product's formulation, such as UV-filters (sunscreens), phthalates (plasticizers and preservatives), synthetic musks (fragrances), parabens and other antimicrobial agents (antimicrobial preservatives). Others are non-intended added substances that may result from the manufacturing process or migration from the plastic packaging, as with bisphenols and perfluorinated compounds. Some of these endocrine disruptors have been restricted or even banned in cosmetics and PCPs given the high risk they pose to health. Thus, the development of fast, sensitive and precise methods for the identification and quantification of these compounds in cosmetics is a substantial need in order to ensure consumer safety and provide insight into the real risk of human exposure. The present work aims at reviewing the more recently developed analytical methods published in the literature for the determination of endocrine disrupting chemicals in cosmetics and PCPs using chromatographic techniques, with a focus on sample treatment and the quality of analytical parameters.


Asunto(s)
Cosméticos , Disruptores Endocrinos , Perfumes , Humanos , Parabenos , Conservadores Farmacéuticos
10.
Chemosphere ; 273: 128603, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33082003

RESUMEN

Ultraviolet filters (UV-filters) are specific chemicals that absorb and reflect UVA and UVB radiation from the sun. They are regularly used in sunscreens and in other personal care products (PCPs), and in products like plastics, adhesives, toys, or furniture finishes. This work develops and validates a new method to determine concentrations of UV-filters (BP-1, BP-2, BP-3, BP-6, BP-8, 4-OH-BP, THB, AVB) in human nail samples. Nails are easily available and are considered to be suitable indicators of cumulative and continued exposure to harmful chemicals. The treatment of nail samples includes microwave assisted digestion/extraction (MAE) in a methanolic solution of o-phosphoric acid (0.05 mol L-1) followed by analyte determination using ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS/MS) in multiple reaction monitoring mode. The analytes were separated in less than 10 min. The digestion procedure was optimized using multivariate techniques. Matrix-matched calibration with a pig hoof matrix was used for validating the method. A study of accuracy with spiked blank samples was also conducted. The calculated detection limits varied between 0.2 and 1.5 ng g-1, and quantification limits between 1.0 and 5.0 ng g-1. The trueness of the method was an estimation of the recovery, which was between 90.2% and 112.2%; with an estimated precision (relative standard deviation, % RSD) lower than 12.3% for all UV-filters. Nail samples were obtained from 22 volunteers (male and female). The results showed that BP-1 and BP-3 mainly bioaccumulate in human nails.


Asunto(s)
Uñas , Espectrometría de Masas en Tándem , Animales , Cromatografía Líquida de Alta Presión , Digestión , Femenino , Humanos , Masculino , Protectores Solares , Porcinos
11.
Talanta ; 208: 120429, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-31816786

RESUMEN

Rapid industrialization has resulted in a progressive increase in human exposure to hazardous chemicals. The present work develops and validates a new method to determinate 18 endocrine disrupting chemicals (EDCs) in human nail samples. In contrast to other common biological samples, nail sampling is non-invasive and since they take several months to grow out, they are well suited for measuring and reflecting the cumulative exposure to harmful substances in the long term. A digestion of samples with a 0.04 M solution of sodium hydroxide is carried out followed by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS), working in multiple-reaction-monitoring (MRM) mode. The compounds were separated in 8 min. Multivariate optimization strategies were used for the optimization of the parameters that affects the digestion procedure. The validation was developed using a matrix-matched calibration and a recovery assay with spiked samples. The limits of detection and quantification ranged from 0.3 to 1.2 ng g-1 and from 1 to 5 ng g-1, respectively. Recovery rates for spiked samples were between 88% and 113% and the relative standard deviation (% RSD) was lower than 12.7% for all studied EDCs. The method was applied for the analysis of these compounds in human nail samples from volunteers. All samples tested positive for several of the analyzed EDCs.


Asunto(s)
Disruptores Endocrinos/análisis , Uñas/química , Adulto , Compuestos de Bencidrilo/análisis , Monitoreo Biológico , Carbanilidas/análisis , Niño , Cromatografía Líquida de Alta Presión/métodos , Femenino , Fluorocarburos/análisis , Humanos , Masculino , Parabenos/análisis , Fenoles/análisis , Espectrometría de Masas en Tándem/métodos
12.
Talanta ; 192: 508-533, 2019 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-30348425

RESUMEN

Emerging contaminants are a heterogeneous group of chemicals that includes daily personal care products and pharmaceuticals (PPCPs), flame retardants, endocrine disrupting chemicals (EDCs) and nanoparticles (NPs). The present work is an overview focused in the research published in the scientific literature for the determination of this type of pollutants in sewage sludge samples in the last 5 years. Instrumental and sample preparation methods for the detection and quantification of the analytes of interest are reviewed, with an emphasis on the sample treatment techniques. Liquid chromatography (LC) and gas chromatography (GC) coupled to mass spectrometry are generally employed as the analytical technique of preference. Sample preparation techniques include conventional methods such as Soxhlet, solid-phase extraction (SPE), pressurized liquid extraction (PLE) or ultrasound-assisted extraction (UAE), but also other recent techniques, including novel microextraction techniques such as microextraction by packed sorbent (MEPS) or solid-phase microextraction (SPME).

13.
Rev. clín. med. fam ; 5(3): 202-205, oct. 2012. tab
Artículo en Español | IBECS (España) | ID: ibc-111488

RESUMEN

Un paciente sin cita es algo muy frecuente en Atención Primaria (AP) y puede llegar a ser problemático. Estos pacientes ponen a prueba al Médico de Familia, ya que ha de saber valorar si la consulta no debe demorarse, a la vez que ha de hacer educación sanitaria, para que los pacientes sigan los cauces habituales para la demanda de atención. Invitamos a la reflexión y mostramos que no por ser una consulta de última hora tiene menos importancia, por lo que hemos de dedicarle el tiempo necesario para llevar a cabo una entrevista clínica correcta y hacer un diagnóstico diferencial, descartando patologías de gran importancia que pudiera presentar nuestro último paciente de la mañana (AU)


A patient without an appointment is quite a common occurrence in Primary Health care, and can be a problem. These patients test the family doctor, as he/she has to be able to judge whether the appointment should, or should not, be delayed, while at the same time giving healthcare education, so that the patients learn to follow the usual channels to obtain care. We invite reflection and show that in spite of being a last-minute consultation, it is no less important, which is why we should dedicate the necessary time to carry out a proper clinical interview and make a differential diagnosis, ruling out any important pathologies which our last patient of the morning could be suffering from (AU)


Asunto(s)
Humanos , Masculino , Adulto , Citas y Horarios , Educación en Salud/métodos , Educación en Salud/tendencias , Diagnóstico Diferencial , Relaciones Profesional-Paciente , Embolia Pulmonar/complicaciones , Embolia Pulmonar/diagnóstico , Anticoagulantes/uso terapéutico , Atención Primaria de Salud/métodos , Atención Primaria de Salud/tendencias , Medicina Familiar y Comunitaria/métodos , Dolor en el Pecho/epidemiología , Dolor en el Pecho/etiología , Electrocardiografía/tendencias , Electrocardiografía
14.
J Antimicrob Chemother ; 58(5): 1082-5, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16950822

RESUMEN

BACKGROUND: The increasing prevalence of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae will probably trigger a rise in the use of carbapenems. The effect of these antibiotics on the risk of involvement of ESBL-producing organisms in serious infections is unclear. METHODS: Retrospective analysis of 2172 episodes of healthcare-associated bacteraemia diagnosed during a 3 year period in a teaching hospital. Putative risk factors included demographics, co-morbidities, previous isolation of an ESBL-producing organism and exposure to antibiotics. Univariate and multivariate analysis of the association of risk factors with ESBL-producing organisms was performed in the entire series of bacteraemic episodes and in those due to Escherichia coli or Klebsiella spp. RESULTS: In the entire series, prior isolation of an ESBL-producing organism [odds ratio (OR) 5.9 (3.02, 11.5)]; an ultimately/finally fatal co-morbidity [OR 2.8 (1.55, 4.95)]; renal transplantation [OR 4.3 (1.96, 9.63)]; a urinary source [OR 4.2 (2.22, 7.84)]; shock [OR 2.4 (1.35, 4.1)] and previous use of cephalosporins [OR 2.6 (1.54, 4.51)], carbapenems [OR 2.5 (1.24, 5.05)] and glycopeptides [OR 0.4 (0.13, 0.93)] were significantly associated with ESBL-producing E. coli or Klebsiella spp. by multivariate analysis. Prior isolation of an ESBL-producing organism, an ultimately/finally fatal co-morbidity, renal transplantation, and previous use of cephalosporins and carbapenems were also significant in the analysis restricted to episodes due to E. coli or Klebsiella spp. CONCLUSIONS: In patients with healthcare-associated bacteraemia, prior use of carbapenems may be only second to cephalosporins as the most significant antibiotic exposure associated with the involvement of ESBL-producing organisms.


Asunto(s)
Bacteriemia/microbiología , Carbapenémicos/efectos adversos , Infecciones por Escherichia coli/microbiología , Escherichia coli/enzimología , Infecciones por Klebsiella/microbiología , Klebsiella/enzimología , beta-Lactamasas/biosíntesis , Adulto , Anciano , Bacteriemia/etiología , Carbapenémicos/uso terapéutico , Infección Hospitalaria/microbiología , Resistencia a Medicamentos , Escherichia coli/aislamiento & purificación , Infecciones por Escherichia coli/etiología , Femenino , Humanos , Klebsiella/aislamiento & purificación , Infecciones por Klebsiella/etiología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA