RESUMO
Autism spectrum disorder (ASD) is a complex developmental disorder in which communication and behavior are affected. A number of studies have investigated potential biomarkers, including uremic toxins. The aim of our study was to determine uremic toxins in the urine of children with ASD (143) and compare the results with healthy children (48). Uremic toxins were determined with a validated high-performance liquid chromatography coupled to mass spectrometry (LC-MS/MS) method. We observed higher levels of p-cresyl sulphate (pCS) and indoxyl sulphate (IS) in the ASD group compared to the controls. Moreover, the toxin levels of trimethylamine N-oxide (TMAO), symmetric dimethylarginine (SDMA), and asymmetric dimethylarginine (ADMA) were lower in ASD patients. Similarly, for pCS and IS in children classified, according to the intensity of their symptoms, into mild, moderate, and severe, elevated levels of these compounds were observed. For mild severity of the disorder, elevated levels of TMAO and comparable levels of SDMA and ADMA for ASD children as compared to the controls were observed in the urine. For moderate severity of ASD, significantly elevated levels of TMAO but reduced levels of SDMA and ADMA were observed in the urine of ASD children as compared to the controls. When the results obtained for severe ASD severity were considered, reduced levels of TMAO and comparable levels of SDMA and ADMA were observed in ASD children.
Assuntos
Transtorno do Espectro Autista , Toxinas Urêmicas , Humanos , Criança , Cromatografia Líquida , Espectrometria de Massas em Tandem , Sulfatos , ArgininaRESUMO
In this study, the levels of concentration of homocysteine thiolactone (HTL), cysteine (Cys), and cysteinylglycine (CysGly) in the urine of autistic and non-autistic children were investigated and compared. HTL has never been analyzed in autistic children. The levels of low molecular weight sulfur compounds in the urine of both groups were determined by validated methods based on high-performance liquid chromatography with spectrofluorometric and diode-array detectors. The statistical data show a significant difference between the examined groups. Children with autism were characterized by a significantly higher level of HTL (p = 5.86 × 10-8), Cys (p = 1.49 × 10-10) and CysGly (p = 1.06 × 10-8) in urine compared with the control group. A difference in the p-value of <0.05 is statistically significant. Higher levels of HTL, Cys, and CysGly in the urine of 41 children with autism, aged 3 to 17, were observed. The obtained results may indicate disturbances in the metabolism of methionine, Cys, and glutathione in some autistic patients. These preliminary results suggest that further research with more rigorous designs and a large number of subjects is needed.
Assuntos
Transtorno Autístico/urina , Cisteína/urina , Homocisteína/análogos & derivados , Compostos de Enxofre/urina , Adolescente , Transtorno Autístico/patologia , Criança , Pré-Escolar , Dipeptídeos/urina , Feminino , Homocisteína/urina , Humanos , Masculino , Peso MolecularRESUMO
The aim of this study was to investigate and compare the levels of concentration of modified nucleosides in the urine of autistic and healthy children. The compounds have never been analyzed before. The levels of nucleosides in the urine of both groups were determined by validated high performance liquid chromatography coupled to mass spectrometry (LC-MS/MS) method using multiple reaction monitoring (MRM) mode. Chromatographic separation was achieved with HILIC column and tubercidin was used as the internal standard for the quantification of urinary nucleosides. The within run accuracy and precision ranged from 89 to 106% and from 0.8% to 4.9%, respectively. Lower levels of O-methylguanosine, 7-methylguanosine, 1-methyladenosine, 1-methylguanine, 7-methylguanine and 3-methyladenine in the urine of 22 children with autism, aged 3 to 16 were observed. The differences were not observed in 20 healthy volunteers, in a similar age group. These findings show that modified nucleosides there are metabolic disturbances and nutritional deficiencies in autistic children.
Assuntos
Adenina/análogos & derivados , Adenosina/análogos & derivados , Transtorno Autístico/urina , Guanina/análogos & derivados , Guanosina/análogos & derivados , Adenina/urina , Adenosina/urina , Adolescente , Transtorno Autístico/diagnóstico , Criança , Pré-Escolar , Cromatografia Líquida , Feminino , Guanina/urina , Guanosina/urina , Humanos , Masculino , Espectrometria de MassasRESUMO
The number of pollutants and chemicals with the potential to reach the environment is still largely unknown, which poses great challenges for researchers in various fields of science, environmental scientists, and analytical chemists. Chromatographic techniques, both gas chromatography (GC) and liquid chromatography (LC) coupled with different types of detection, are now invaluable tools for the identification of a wide range of chemical compounds and contaminants in water. This review is devoted to chromatographic techniques GC-MS, GC-Orbitrap-MS, GC-MS/MS, GC-HRMS, GC × GC-TOFMS, GC-ECD, LC-MS/MS, HPLC-UV, HPLC-PDA, UPLC-QTOFMS, used to determinate emerging organic contaminants in aquatic media, mainly in urban water, published in the scientific literature over the past several years. The article also focuses on sample preparation methods used in the analysis of aqueous samples. Most research focuses on minimizing the number of sample preparation steps, reducing the amount of solvents used, the speed of analysis, and the ability to apply it to a wide range of analytes in a sample. This is extremely important in the application of sensitive and selective methods to monitor the status of urban water quality and assess its impact on human health.
RESUMO
Clay vessels have a wide variety of functions in social activities in the Hallstatt period. In addition to food storage and processing, they were used for ritual purposes and as funerary vessels. The paper presents the results of archaeological and chromatographic studies of 31 vases from two different Hallstatt culture sites in lower Silesia (Poland). The investigations included vessels fragments from the Domaslaw cemetery and from the Milejowice settlement. The chromatographic analyses focused on fatty acids and biomarkers and made it possible to identify the most likely sources of substances they came into contact with during use. The c-means and hierarchical cluster analyses showed that grave vessels differed from settlement ceramics. Thus, conclusions on the diverse vessel functions could be made.
Assuntos
Cemitérios , Cerâmica , Polônia , Cerâmica/história , Humanos , Arqueologia , História Antiga , Ácidos Graxos/metabolismoRESUMO
The aim of this research was to explore the innovative use of natural additives, containing phytochemicals with proven antimicrobial effects, in the production of epoxy-glass composites. This study was based on information regarding the antimicrobial effects of phytochemicals present in Cistus incanus, Zingiber officinale, and Armoracia rusticana. The additives were subjected to a gas chromatography (GC) analysis to determine their composition, and, subsequently, they were used to prepare resin mixtures and to produce epoxy-glass composites. Samples of the modified materials were tested against E. coli, S. aureus, and C. albicans. In addition, flammability and durability tests were also performed. It was found that the strongest biocidal properties were demonstrated by the material with the addition of cistus, which caused a reduction of microorganisms by 2.13 log units (S. aureus), 1.51 log units (E. coli), and 0.81 log units (C. albicans). The same material also achieved the most favorable results of strength tests, with the values of flexural strength and tensile strength reaching 390 MPa and 280 MPa, respectively. Public transport is a place particularly exposed to various types of pathogens. Currently, there are no solutions on the railway market that involve the use of composites modified in this respect.
RESUMO
Metabolic disorders and nutritional deficiencies in ASD children may be identified by the determination of urinary-modified compounds. In this study, levels of selected seven modified compounds: O-methylguanosine, 7-methylguanosine, 1-methyladenosine, 1-methylguanine, 7-methylguanine, 3-methyladenine, and 8-hydroxy-2`-deoxyguanosine in the group of 143 ASD children and 68 neurotypical controls were analyzed. An ancillary aim was to verify if the reported levels differed depending on the pathogenetic scoring of ASD (mild deficit, moderate deficit, severe deficit). Elevated O-methylguanosine and 7-methylguanosine levels and significantly lower levels of 3-methyladenine, 1-methylguanine, 1-methyladenosine, 7-methylguanine, and 8-hydroxy-'2'-deoxyguanosine were observed in ASD children compared to controls. O-methylguanosine levels were elevated in the mild and moderate groups, while the levels of 1-methylguanine, 1-methyladenosine, 7-methylguanine, and 8-hydroxy-'2'-deoxyguanosine in the same groups were lower than in neurotypical controls. The reported evidence shows that modified nucleosides/bases can play a potential role in the pathophysiology of ASD and that each nucleoside/base shows a unique pattern depending on the degree of the deficit.
Assuntos
Transtorno do Espectro Autista , Nucleosídeos , Humanos , Criança , Nucleosídeos/urina , Transtorno do Espectro Autista/urina , 8-Hidroxi-2'-DesoxiguanosinaRESUMO
Food ingredients which were prepared or stored in the archeological ceramics are the most frequently used in the study of ceramic vessels with the use of various types of gas chromatographic methods. These include lipids which contain fatty acids and compounds characteristic of various types of food known as archeological biomarkers. The paper shows how the lipid profile analysis and its interpretation can be helpful to explain the source of organic substances preserved in archeological ceramic vessels. The presence of characteristic sterols discriminates between plant (phytosterols) and animal (zoosterols) residues. Based on the calculated proportions of selected fatty acids, the animal residues can be precisely identified as originating from fish, ruminants or monogastric animals. Many authors have created their own methods of interpretation and conclusion, which makes it possible to sort out all the information gathered about the historical purpose of clay vessels. Due to the fact that the presented research still raises some doubts and questions, it is important for the interpretation of the results of chemical analysis to be considered in the archeological context. The ability to properly explain the meaning of the results of analyses is crucial for a better understanding of the life and customs of our ancestors.
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Arqueologia/métodos , Cerâmica/química , História AntigaRESUMO
Modern analytical methods play an important role in archaeological objects, including ceramics. This review focuses on the use of analytical methods such as: gas chromatography coupled mass spectrometry, Fourier transform infrared spectroscopy, time-of-flight secondary ion mass spectrometry (ToF-SIMS), powder X-ray diffraction with thermal analysis to study the chemical and mineralogical composition of archaeological samples and organic residues preserved inside. In this paper, special attention was paid to the ToF-SIMS method, which allows the determination of characteristic ions on the surface of ceramic samples.
Assuntos
Arqueologia , Cerâmica/análise , Cerâmica/normas , Cromatografia Gasosa-Espectrometria de Massas/normas , Controle de Qualidade , Espectrometria de Massa de Íon Secundário/normas , Espectroscopia de Infravermelho com Transformada de Fourier/normas , Temperatura , Difração de Raios XRESUMO
The analysis of the composition of organic residues present in pottery is an important source of information for historians and archeologists. Chemical characterization of the materials provides information on diets, habits, technologies, and original use of the vessels. This review presents the problem of analytical studies of archeological materials with a special emphasis on organic residues. Current methods used in the determination of different organic compounds in archeological ceramics are presented. Particular attention is paid to the procedures of analysis of archeological ceramic samples used before gas chromatography-mass spectrometry. Advantages and disadvantages of different extraction methods and application of proper quality assurance/quality control procedures are discussed.