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1.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1390292

RESUMO

RESUMEN Introducción: los anticuerpos antinucleares son muy utilizados en la práctica médica como marcadores de autoinmunidad y en el diagnóstico de enfermedades autoinmunes. Sin embargo, estos anticuerpos son la expresión de otros trastornos más allá de las colagenopatías e incluso pueden estar presentes en la población aparentemente sana sin representar un riesgo para la salud de estos en el futuro. Objetivo: determinar la prevalencia de anticuerpos antinucleares en médicos residentes aparentemente sanos del Hospital de Clínicas, San Lorenzo, en el año 2021. Material y métodos: se realizó un estudio descriptivo prospectivo y transversal en 150 médicos residentes aparentemente sanos en el Hospital de Clínicas de la ciudad de San Lorenzo, Paraguay, en el periodo de junio a septiembre de 2021. Se determinaron los anticuerpos antinucleares tipo inmunoglobulina G mediante inmunofluorescencia indirecta en células HEp-2. Resultados: la prevalencia de anticuerpos antinucleares fue 11,3%. La mayoría de los sujetos con resultados positivos fueron mujeres (76,5%, p<0,05). Las titulaciones más frecuentes fueron 1:80 y 1:160 por igual (35,3% cada una) y entre los sujetos reactivos el patrón nuclear granular fino denso (AC2) fue el más prevalente (52,9%). Conclusión: la prevalencia de anticuerpos nucleares fue 11,3%, la mayor frecuencia se vio en mujeres, las titulaciones más comunes fueron 1:80 y 1:160 y el patrón más habitual fue el nuclear granular fino denso.


ABSTRACT Introduction: Antinuclear antibodies are widely used in medical practice as autoimmunity markers and in the diagnosis of autoimmune diseases. However, these antibodies are the expression of other disorders beyond collagenopathies and may even be present in the apparently healthy population without representing a risk to their health in the future. Objective: To determine the prevalence of antinuclear antibodies in apparently healthy residents of the Hospital de Clínicas, San Lorenzo, in 2021. Material and methods: A descriptive, prospective and cross-sectional study was carried out in 150 apparently healthy resident physicians at the Hospital de Clínicas in the city of San Lorenzo, Paraguay, from June to September 2021. Immunoglobulin G-type antinuclear antibodies were determined using Indirect immunofluorescence in HEp-2 cells. Results: The prevalence of antinuclear antibodies was 11.3%. Most of the subjects with positive results were women (76.5%, p <0.05). The most frequent titrations were 1:80 and 1:160 equally (35.3% each) and among the reactive subjects the nuclear dense fine speckled pattern (AC2) was the most prevalent (52.9%). Conclusion: The prevalence of nuclear antibodies was 11.3%, the highest frequency was seen in women, the most common titers were 1:80 and 1: 160 and the most common pattern was the nuclear dense fine speckled.

2.
Access Microbiol ; 3(11): 000280, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35018325

RESUMO

INTRODUCTION: Infections caused by fast growing mycobacteria have increased markedly worldwide. They are normally associated with trauma, surgery or cosmetic interventions. Paraguay has a deficit in sanitary control including clinics, private practices, and aesthetic centres. This situation is accompanied by the easy access to drugs, which leads to the performance of exclusively medical aesthetic procedures by people without professional knowledge or training. CASE REPORT: A 26-year-old female patient comes to a medical consultation with pain and bruising in the abdominal area with more than 3 months of progression, without fever or apparent cause. Later, she confessed to the application of subcutaneous injections of 'growth hormones' at the gym. Excisional biopsy of the lesions was carried out for anatomopathological and microbiological studies. In addition, the use of polymerase chain reaction analysis was indicated because of the strong suspicion of an atypical mycobacterial infection. The Ziehl-Neelsen staining was negative for BAAR, and the PAS-Hematoxylin negative for fungal elements. When performing the culture, the growth of atypical mycobacteria was observed on chocolate and blood agar medium culture. Through the polymerase chain reaction study, it was possible to identify the atypical mycobacterium as 'Mycobacterium abscessus'. CONCLUSION: The irresponsible application of medications by people without professional authorization or biosafety precautions can lead to the development atypical infections that are difficult to diagnose and treat. This situation could lead to serious complications and even death.

4.
Sci Total Environ ; 687: 355-368, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31207525

RESUMO

A single workflow based on three approaches (target, suspected and non-target screening) using liquid chromatography coupled to quadrupole-time-of-flight mass spectrometry (LC-QTOF-MS) in data independent acquisition mode (DIA) was developed to assess the presence of emerging pollutants (EPs) in water and sediments from a Mediterranean River Basin. Identification of potential contaminants was based on mass accuracy, isotopic ratio pattern, theoretical fragmentation, and retention time using Waters UNIFI software. In the suspect screening against a library containing 2200 components, 68 contaminants were tentatively identified, 6 of which were confirmed and quantified with analytical standards. Non-target screening (NTS) required additional manual processing and the aid of an on-line database (ChemSpider) to tentatively identify compounds. Eprosartan, an antihypertensive drug not included in the library used for suspected screening, was confirmed and semi-quantified. The identification of Eprosartan proved the workflow to be functional for NTS. Target screening of 171 pesticides and 33 pharmaceuticals and personal care products (PPCPs) including the compounds confirmed using suspect (6) and non target (1) screening achieved monitoring of the most abundant contaminants from the head to the mouth of the Turia basin to establish their spatial distribution. QTOF-MS screening versatility with its high-resolution capability allows for a comprehensive assessment of EPs in the aquatic environment.

5.
Environ Toxicol Chem ; 38(10): 2137-2144, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31233235

RESUMO

Microcystin-LR is a toxin commonly produced by the cyanobacterium Microcystis aeruginosa. It is present in harmful algal blooms and is a concern for both human and environmental health in Canadian freshwater systems. Previous studies have investigated the toxicity of microcystin-LR to other organisms such as fish; however, it is important to assess its toxicity to native freshwater mussels (family Unionidae), which are considered imperiled. The present study examined the toxicity of microcystin-LR to fatmucket mussels (Lampsilis siliquoidea) at 2 different life stages. Juvenile mussels were exposed to microcystin-LR in a 28-d chronic test, and glochidia underwent a 72-h acute toxicity test. There was no significant relationship between glochidia viability and microcystin-LR concentration. The median lethal concentration (LC50) value for juvenile mussels after 28 d of exposure was 2.1 µg/L. To determine the environmental relevance of the observed toxicity, an environmental exposure distribution was created using Canadian and Canadian-US Great Lakes microcystin measurements. The 28-d LC50 value (2.1 µg/L) was greater than those values that occurred in the environment 95% of the time; however, the LC10 (0.45 µg/L) and LC25 (0.97 µg/L) values were not greater than the measured microcystin environmental values. This finding indicates that microcystins may exert toxic effects on juvenile mussels at environmentally relevant concentrations. Further investigation should be considered in terms of prolonged exposure to persistent microcystin-LR, and toxicity to sensitive species at different life stages. Environ Toxicol Chem 2019;38:2137-2144. © 2019 SETAC.


Assuntos
Bivalves/efeitos dos fármacos , Microcistinas/toxicidade , Microcystis/metabolismo , Animais , Bivalves/crescimento & desenvolvimento , Canadá , Proliferação Nociva de Algas , Dose Letal Mediana , Toxinas Marinhas , Testes de Toxicidade Aguda , Testes de Toxicidade Crônica
6.
Mar Pollut Bull ; 131(Pt A): 174-179, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29886934

RESUMO

Two Guillemot carcases were dissected, each providing 12 discrete tissue samples and 3 samples of partially digested food. One hundred and five PCBs from the 209 PCBs determined by GCxGC-ToFMS were detected. The relative proportions of individual PCBs did not vary greatly within tissue types, although the PCB profile from undigested food could be distinguished. Enantiomer fractions (EFs) were determined for CB-95, CB-136 and CB-149 by GC-HRqToFMS. EFs in the partially digested food were near racemic, with high levels of enrichment for E1 CB-95 in the kidneys and liver (EF of 0.80 and 0.84 respectively). This provides some of the clearest evidence to date that fractionation takes place in the organs where metabolic biotransformation and elimination of PCBs occurs. Our findings also confirm the ability of non-lethal sampling techniques, such as collection of small (<1 g) blood samples, to provide PCB signatures that are representative of an individual organism.


Assuntos
Aves/metabolismo , Bifenilos Policlorados/análise , Bifenilos Policlorados/farmacocinética , Animais , Biotransformação , Bifenilos Policlorados/química , Estereoisomerismo , Distribuição Tecidual , Reino Unido , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Poluentes Químicos da Água/farmacocinética
7.
J Chromatogr A ; 1536: 88-95, 2018 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-28712554

RESUMO

This study reports the first application of comprehensive two-dimensional gas chromatography coupled to a high-resolution quadrupole time-of-flight mass spectrometer (GC×GC/HRQTOF-MS) for the characterization of naphthenic acid fraction compounds (NAFCs) from the Alberta Oil Sands. High resolution mass spectrometry (HRMS) significantly increased the coverage of NAFCs in the mixture and allowed the differentiation of NAFCs from several chemical classes. It was demonstrated that GC×GC, in combination with the high mass accuracy and precision of the HRQTOF-MS, could distinguish chemical species with the C3 vs SH4 mass split at a much lower resolving power than required with direct infusion experiments. Mass defect plots were useful for visualizing the complex datasets generated by GC×GC/HRQTOF-MS and led to the identification of 1105 chemical species with unique elemental compositions (<5ppm mass accuracy). Mass defect plots were shown to be a powerful screening tool and enabled the detection of extensive isomer series from the SO2 chemical class, some of which have not been previously reported in oil sands related samples. The GC×GC/HRQTOF-MS approach is expected to improve NAFC monitoring programs since the technique allows the qualitative analysis of individual NAFCs and provides unique fingerprints via isomer distributions which may assist in future fingerprinting studies.


Assuntos
Ácidos Carboxílicos/química , Técnicas de Química Analítica/métodos , Cromatografia Gasosa-Espectrometria de Massas , Alberta , Ácidos Carboxílicos/análise , Campos de Petróleo e Gás , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química
8.
Anal Bioanal Chem ; 409(21): 4959-4969, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28634756

RESUMO

Microcystins are cyclic heptapeptide hepatotoxins produced by cyanobacteria in freshwater. Sample preparation for the analysis of these cyanotoxins in water from algal blooms can take up to several days due to the matrix complexity and the low detection limits required to comply with current legislation. Moreover, there is a large number of unknown microcystins that could potentially exist in the environment resulting from different amino acid substitutions into the microcystin skeletal structure. To tackle these problems, the present study involved the development of a high throughput method based on on-line solid phase extraction coupled to liquid chromatography that could provide quantitative results for 12 microcystin variants (LR, YR, RR, HtyR, HilR, WR, LW, LA, LF, LY, Dha7-LR, and Dha7-RR) and anatoxin-A in less than 3 h with detection limits between 0.004 and 0.01 µg L-1 and expanded uncertainty between 4 and 14%. Data-dependent acquisition was employed for the non-targeted analysis of these cyanotoxins. Filtering the data based on structure diagnostic fragments, two unknown microcystin variants not previously reported in the literature were detected. The structures Leu1-microcystin-Met(O)R and Leu1-microcystin-LY were fully characterized by accurate mass measurement, collision-induced dissociation, and fragmentation prediction software.


Assuntos
Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Microcistinas/análise , Extração em Fase Sólida/métodos , Tropanos/análise , Toxinas de Cianobactérias , Limite de Detecção
9.
Environ Sci Technol ; 51(3): 1518-1526, 2017 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-28004576

RESUMO

The study of not only main flame retardants but also of related degradation products or impurities has gained attention in the last years and is relevant to assess the safety of our consumer products and the emission of potential contaminants into the environment. In this study, we show that plastics casings of electric/electronic devices containing TBBPA contain also a complex mixture of related brominated chemicals. These compounds were most probably coming from impurities, byproducts, or degradation products of TBBPA and TBBPA derivatives. A total of 14 brominated compounds were identified based on accurate mass measurements (formulas and tentative structures proposed). The formulas (or number of bromine elements) for 19 other brominated compounds of minor intensity are also provided. A new script for the recognition of halogenated compounds based on combining a simplified isotope pattern and mass defect cluster analysis was developed in R for the screening. The identified compounds could be relevant from an environmental and industrial point of view.


Assuntos
Retardadores de Chama , Plásticos , Bromo/química , Eletrônica , Hidrocarbonetos Bromados , Isótopos , Bifenil Polibromatos
10.
Environ Sci Technol ; 50(23): 12678-12685, 2016 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-27791360

RESUMO

Chemical pollution is hypothesized to be one of the factors driving the strong decline of the critically endangered European eel population. Specifically, the impact of contaminants on the quality of spawning eels and subsequent embryo survival and development has been discussed as crucial investigation point. However, so far, only very limited information on potential negative effects of contaminants on the reproduction of eels is available. Through the combination of nontargeted ultrahigh-resolution mass spectrometry and multidimensional gas chromatography, combined with more-conventional targeted analytical approaches and multimedia mass-balance modeling, compounds of particular relevance, and their maternal transfer in artificially matured European eels from the German river Ems have been identified. Substituted diphenylamines were, unexpectedly, found to be the primary organic contaminants in the eel samples, with concentrations in the µg g-1 wet weight range. Furthermore, it could be shown that these contaminants, as well as polychlorinated biphenyls (PCBs), organochlorine pesticides, and polyaromatic hydrocarbons (PAHs), are not merely stored in lipid rich tissue of eels but maternally transferred into gonads and eggs. The results of this study provide unique information on both the fate and behavior of substituted diphenylamines in the environment as well as their relevance as contaminants in European eels.


Assuntos
Difenilamina , Análise de Fourier , Ciclotrons , Cromatografia Gasosa-Espectrometria de Massas , Praguicidas , Bifenilos Policlorados , Poluentes Químicos da Água
11.
Chemosphere ; 158: 116-23, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27258902

RESUMO

Fresh and used aircraft engine lubricants (Mobil Jet Oil II) were analysed using a Fourier Transform Ion Cyclotron Resonance Mass Spectrometer (FTICRMS) and comprehensive two dimensional gas chromatography with high resolution time of flight mass spectrometry (GCxGC-HRTOFMS). The composition of the fresh oil was established, with special focus to its tricresyl phosphate (TCP) content as this has formed the focus for most investigations into aerotoxic syndrome. The results showed that only four TCP isomers were present at detectable levels in the fresh oil: mmm-TCP, mmp-TCP, ppm-TCP and ppp-TCP. The results indicate that the formulation of Mobile Jet Oil II does not contain the more toxic ortho substituted TCP isomers at concentrations above 0.0005%. The temperatures of jet engines during operation are greater than 200 °C which creates the potential to alter the composition of the original oil and create other toxic compounds. The results show there may be a significant risk from alkylated cresyl phosphates, which were identified in the used oils at concentrations calculated in the range of 0.13-0.69%. w/w. Several xylenyl and ethylphenyl phosphates have been shown to exhibit a similar toxicity to ortho substituted TCP isomers which makes there discovery in used oil significant. These compounds should be included in future aircraft air quality studies and when assessing the risks and causes of aerotoxic syndrome.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Óleos/análise , Tritolil Fosfatos/análise , Poluentes Atmosféricos/análise , Aeronaves , Aviação , Monitoramento Ambiental , Humanos , Exposição por Inalação , Isomerismo , Espectrometria de Massas , Organofosfatos/química , Oxigênio/química , Fosfatos/análise , Reprodutibilidade dos Testes , Risco , Espectroscopia de Infravermelho com Transformada de Fourier , Síndrome
12.
Anal Chem ; 86(15): 7666-73, 2014 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-25001115

RESUMO

During the bitumen extraction from the oil sands of Alberta, large volumes of process water containing naphthenic acids are stored in tailing ponds. The naphthenic acids along with other components in the processed waters are known to be toxic in aquatic environments. In view of the complex matrix and the toxicity of the processed waters, there is a need for complementary analytical techniques for comprehensive characterization of the naphthenic acid mixtures. This study reports the online gas chromatographic separation of naphthenic acid mixtures prior to ultrahigh resolution mass spectrometry detection, using electron and chemical ionization. Two oil sands processed water samples and two groundwater samples were characterized to evaluate the performance of the instrumental technique. The high mass resolution of the system enabled visualization of the data using Kendrick mass defect plots. The addition of gas chromatographic separations enabled visualization of the data as unique compound class elution fingerprints. The technique is demonstrated to be a valuable tool for chemical fingerprinting of naphthenic acids.

13.
Chemosphere ; 82(5): 739-44, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21122893

RESUMO

Fish oils are one of the main sources of ω-3 fatty acids. However, they can present elevated levels of some lipophilic pollutants, such as hexabromocyclododecanes (HBCDs). Since data about HBCDs in fish oil samples are very limited, in this study, 25 samples of fish oil for feed and food have been analyzed. Total HBCDs, as well as, α-, ß- and γ-diastereoisomers have been determined. Total HBCDs ranged from 0.09 to 26.8ngg(-1), with higher concentrations in fish oil for feed (average value of 9.69ngg(-1)) than those for food (1.14ngg(-1)). Concentrations of α-HBCD (average value of 4.12ngg(-1) in feed samples and 0.48ngg(-1) in food samples) and γ-HBCD (5.05 and 0.43ngg(-1) respectively) were higher than that of ß-HBCD (0.52 and 0.19ngg(-1) respectively) in most of the samples. However, none of them was predominant in the samples. Concentrations of HBCDs were compared to concentrations of other pollutants and correlation between dioxin and dioxin-like PCBs levels and HBCDs levels were observed. Intake of HBCDs was calculated for fish oil with human consumption purposes and it ranged from 0.08 to 5.38ng HBCDsd(-1), which could contribute significantly to HBCDs total intake. Enantiomeric fractions were also determined. No clear enrichment was observed for γ-HBCD, while (-)-α-HBCD enrichment was detected in some samples.


Assuntos
Ração Animal/análise , Óleos de Peixe/análise , Retardadores de Chama/análise , Contaminação de Alimentos/análise , Hidrocarbonetos Bromados/análise , Animais , Suplementos Nutricionais/análise , Ácidos Graxos Ômega-3/análise , Humanos , Isomerismo , Poluentes Químicos da Água/análise
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