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1.
Methods Appl Fluoresc ; 12(1)2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-37956440

RESUMO

In this study, QuEChERS extraction was combined with dispersive liquid-liquid microextraction (DLLME) to extract pesticides from tropical fruits for determination by a highly accurate and sensitive liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-QTOF-MS/MS) system. The QuEChERS method served as a matrix clean-up tool and the DLLME method preconcentrated the analytes for their determination at trace levels. All parameter variables of the DLLME method were optimized to improve the extraction output and lower the limits of detection and quantification (LOD and LOQ) for all the analytes. Under the optimum experimental conditions, the LOD and LOQ values were found in the range of 0.004-0.013 and 0.27-0.61µg l-1, respectively. The detection limits achieved by direct LC-QTOF-MS/MS analysis were increased by about 10-260 folds using the optimized DLLME method. To assess the accuracy and applicability of the developed method, spike recovery experiments on tropical fruits were carried out. The matrix matching calibration method was used to enhance the quantification accuracy of the analytes in kiwi, pineapple, and mango matrices, with percent recoveries ranging between 89 and 117%.


Assuntos
Microextração em Fase Líquida , Praguicidas , Praguicidas/análise , Espectrometria de Massas em Tandem/métodos , Microextração em Fase Líquida/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Frutas/química , Cromatografia Líquida
2.
Environ Monit Assess ; 191(11): 692, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31667640

RESUMO

In this study, a rapid and effective dispersive solid-phase microextraction (d-SPME) method was developed to preconcentrate Pd from aqueous extract of soil samples by slotted quartz tube-flame atomic absorption spectrometry (SQT-FAAS). The unique properties of magnetic nanoparticles (MNPs) were used to directly isolate Pd from the sample solutions without the need for complexation. Significant parameters of the extraction method such as magnetic nanoparticle type and amount, pH and amount of buffer solution, amount of eluent, and mixing type and period were optimized together with other instrumental parameters to boost the absorbance signal of Pd. An SQT was fitted onto the burner head to boost the interaction between Pd atoms and hollow cathode lamp radiation to enhance absorbance signals. The limit of detection (LOD) and limit of quantification (LOQ) values for Pd determined (d-SPME-MNP-SQT-FAAS) were 6.4 and 21.4 ng/mL, respectively. The percentage relative standard deviation of the developed method was calculated as 6.6%. The method was applied to soil samples taken from the campus area and spiked recovery experiments were performed to evaluate the method's accuracy/applicability. Satisfactory percent recovery results (90-101%) were obtained for different spiked concentrations and this proved the accuracy/applicability of the method.


Assuntos
Paládio/análise , Poluentes do Solo/análise , Monitoramento Ambiental/métodos , Limite de Detecção , Microextração em Fase Líquida/métodos , Magnetismo , Nanopartículas de Magnetita , Quartzo/química , Solo , Microextração em Fase Sólida , Espectrofotometria Atômica/métodos , Água/análise
3.
Environ Monit Assess ; 190(7): 437, 2018 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-29951716

RESUMO

This study describes the determination of trace levels of copper by slotted quartz tube atomic absorption spectrometry after dispersive liquid-liquid microextraction. A ligand synthesized from the reaction of salicylaldehyde and 1-naphthylamine was used to form coordinate copper complex prior to extraction. All parameters that influence the output of complex formation, extraction, and instrumental measurement were optimized to enhance the absorbance signal of copper. Under the optimum conditions, about 104-fold enhancement in sensitivity was recorded over the conventional flame atomic absorption spectrometer, corresponding to a 0.51 ng/mL detection limit. The percent relative standard deviation calculated for the lowest concentration (4.8%) indicated high precision for the experimental procedure. Accuracy and applicability of the optimum method were determined by performing spiked recovery tests on urine, lake water, and mineral water samples. Satisfactory recovery results were obtained between 82.2 and 106.3% at four different concentrations. Matrix matching method was also performed to increase the accuracy of quantification, and the percent recovery calculated for 175 ng/mL was 105.14%.


Assuntos
Biota , Cobre/análise , Monitoramento Ambiental/métodos , Ligantes , Microextração em Fase Líquida/métodos , Poluentes Químicos da Água/análise , Limite de Detecção , Quartzo , Espectrofotometria Atômica/métodos
4.
Bioelectromagnetics ; 39(4): 299-311, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29446477

RESUMO

Diabetes mellitus is a metabolic disease that causes increased morbidity and mortality in developed and developing countries. With recent advancements in technology, alternative treatment methods have begun to be investigated in the world. This study aims to evaluate the effect of pulsed magnetic field (PMF) on vascular complications and contractile activities of aortic rings along with Kir6.1 and Kir6.2 subunit expressions of ATP-sensitive potassium channels (KATP ) in aortas of controlled-diabetic and non-controlled diabetic rats. Controlled-diabetic and non-controlled diabetic adult male Wistar rats were exposed to PMF for a period of 6 weeks according to the PMF application protocol (1 h/day; intensity: 1.5 mT; consecutive frequency: 1, 10, 20, and 40 Hz). After PMF exposure, body weight and blood glucose levels were measured. Then, thoracic aorta tissue was extracted for relaxation-contraction and Kir6.1 and Kir6.2 expression experiments. Blood plasma glucose levels, body weight, and aortic ring contraction percentage decreased in controlled-diabetic rats but increased in non-controlled diabetic rats. PMF therapy repressed Kir6.1 mRNA expression in non-controlled diabetic rats but not in controlled diabetic rats. Conversely, Kir6.2 mRNA expressions were repressed both in controlled diabetic and non-controlled diabetic rats by PMF. Our findings suggest that the positive therapeutic effects of PMF may act through (KATP ) subunits and may frequently occur in insulin-free conditions. Bioelectromagnetics. 39:299-311, 2018. © 2018 Wiley Periodicals, Inc.


Assuntos
Aorta/fisiopatologia , Diabetes Mellitus Experimental/fisiopatologia , Canais KATP/metabolismo , Campos Magnéticos , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Vasoconstrição , Animais , Glicemia/metabolismo , Peso Corporal , Diabetes Mellitus Experimental/metabolismo , Canais KATP/genética , Masculino , Músculo Liso Vascular/fisiopatologia , Canais de Potássio Corretores do Fluxo de Internalização/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar
5.
J Sep Sci ; 40(24): 4740-4746, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29071784

RESUMO

A highly sensitive and simple diode-array high-performance liquid chromatography and liquid chromatography with quadrupole time-of-flight tandem mass spectrometry method was developed for the simultaneous determination of niacin and pyridoxine in pharmaceutical drugs, tap water, and wastewater samples. To determine the in vivo behavior of niacin and pyridoxine, analytes were subjected to simulated gastric conditions. The calibration plots of the diode-array high-performance liquid chromatography and liquid chromatography with quadrupole time-of-flight tandem mass spectrometry method showed good linearity over a wide concentration range with close to 1.0 correlation coefficients for both analytes. The limit of detection/limit of quantitation values for liquid chromatography quadrupole time-of-flight tandem mass spectrometry analysis were 1.98/6.59 and 1.3/4.4 µg/L for niacin and pyridoxine, respectively, while limit of detection/limit of quantitation values for niacin and pyridoxine in high-performance liquid chromatography analysis were 3.7/12.3 and 5.7/18.9 µg/L, respectively. Recovery studies were also performed to show the applicability of the developed methods, and percentage recovery values were found to be 90-105% in tap water and 94-97% in wastewater for both analytes. The method was also successfully applied for the qualitative and quantitative determination of niacin and pyridoxine in drug samples.


Assuntos
Água Potável/química , Niacina/análise , Preparações Farmacêuticas/química , Piridoxina/análise , Águas Residuárias/química , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em Tandem
6.
Int J Biol Macromol ; 104(Pt A): 515-520, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28634058

RESUMO

Perfluorinated compounds (PFCs) such as PFOS and PFOA, are xenobiotics that can be detected worldwide in the environment and humans. PFOS (C8F17SO3-) is a fluorinated organic compound has been used for decades in industrial and commercial products. We investigated the genotoxic and apoptotic impact of PFOS in rat liver using comet assay, micronucleus test and apoptotic gene expression methods for caspase 3, caspase 8 and the protective role of curcumin on the PFOS- induced damage under chronic exposure. In this study, rats were treated either with three different PFOS doses only (0.6, 1.25 and 2.5mg/kg) or one dose of curcumin (80mg/kg) or three different doses of PFOS combined with 80mg/kg dose of curcumin by gavage for 30days at 48h intervals. We evaluated the DNA damage via comet assay and micronucleus test. Doses of PFOS increased micronucleus frequency (p<0.05) and strongly induced DNA damage in liver in two different parameters; i: the damaged cell percentage and ii: genetic damage index. Curcumin prevented the formation of DNA damage induced by PFOS and curcumin substance applied with PFOS caused a decrease in the micronucleus frequency. PFOS increased apoptotic gene expression but curcumin decreased the expression levels of caspase 3 and 8.


Assuntos
Ácidos Alcanossulfônicos/toxicidade , Apoptose/efeitos dos fármacos , Apoptose/genética , Curcumina/farmacologia , Dano ao DNA , Fluorocarbonos/toxicidade , Fígado/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Animais , Caspase 3/genética , Caspase 8/genética , Citoproteção/efeitos dos fármacos , Relação Dose-Resposta a Droga , Poluentes Ambientais/toxicidade , Fígado/metabolismo , Masculino , Ratos , Ratos Wistar
7.
Noro Psikiyatr Ars ; 53(2): 115-119, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28360782

RESUMO

INTRODUCTION: This study aimed to analyze the genotypic characteristics of Friedreich's ataxia (FA) and autosomal dominant ataxias [such as spinocerebellar ataxia (SCA) types 1, 2, 3, and 6] using molecular and biological methods in hereditary cerebellar ataxia considering both clinical and electrophysiological findings. METHODS: The study included 129 indexed cases, who applied to the neurology department and were diagnosed with hereditary cerebellar ataxia through clinical, laboratory, and electrophysiological findings, and 15 sibling patients who were diagnosed through family scanning (144 cases in total); their genetic analyses were also performed. Detailed physical and neurological examinations, pedigree analyses, electroneurography, evoked potentials, cerebral-spinal magnetic resonance imaging, and echocardiographic analyses were performed for all cases. Blood samples were collected from patients, and the genotypic characteristics of autosomal dominant SCA types 1, 2, 3, and 6 were investigated. Statistical analyses were performed with the Statistical Package for the Social Sciences (SPSS Inc; Chicago, IL, USA) 17.0. RESULTS: Almost 50% of patients were defined as FA. Moreover, two SCA1 cases and one SCA6 case were detected. CONCLUSION: In our study, 47.2% of patients with FA had developed hereditary cerebellar ataxia. Ground and autosomal dominant-linked SCA1 and SCA6 were each detected in one family. These data suggest that patients with cerebellar ataxia of hereditary origin should be primarily examined for FA.

8.
Brain Res ; 1624: 479-488, 2015 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-26300221

RESUMO

Early adverse life experiences have been associated with anxiety-like behavior and memory impairment. N-methyl-d-aspartate receptors (NMDARs) play an important role in brain development. Enriched environments are known to positively influence emotional and cognitive functions in the brain. We examined the effects of maternal deprivation (MD) on NMDAR subunits in the hippocampus, locomotor activity, anxiety behaviors, and learning-memory performance of Balb/c mice. We also examined whether these effects could be reversed by raising the offspring in an enriched environment. The mice were separated from their mothers for a single 24h episode on postnatal day (PND) 9. The mice were weaned on day 21 and were housed under either standard (SE) or enriched (EE) environmental conditions. Emotional behaviors and cognitive processes of mice were evaluated using an open field (OF) test, an elevated plus maze (EPM) test, and a Morris water-maze (MWM). NMDAR subunits (GluN1, GluN2A, and GluN2B) mRNA expression levels in the hippocampus were examined by real-time PCR. In OF, MD had no effect on horizontal locomotor activity. MD increased anxiety-like behaviors in the EPM and decreased spatial learning performance in MWM; however, these effects were not reversed by EE. MD (in SE and EE conditions) increased GluN1, GluN2A, and GluN2B mRNA expressions in the hippocampus. In conclusion, MD led to the deterioration of the emotional and cognitive processes during adulthood. Moreover, environmental enrichment did not reverse the deleterious effects of the MD on emotional and cognitive functions and increased the NMDAR levels.


Assuntos
Meio Ambiente , Privação Materna , Transtornos do Humor/etiologia , Receptores de N-Metil-D-Aspartato/metabolismo , Animais , Animais Recém-Nascidos , Peso Corporal , Regulação da Expressão Gênica/fisiologia , Hipocampo/metabolismo , Aprendizagem em Labirinto/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Transtornos do Humor/patologia , Desempenho Psicomotor , RNA Mensageiro/metabolismo , Receptores de N-Metil-D-Aspartato/genética
9.
Indian J Hum Genet ; 19(4): 408-11, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24497704

RESUMO

OBJECTIVES: Estrogen is one of the most crucial hormones participating in the proliferation and carcinogenesis of the prostate glands. Genetic polymorphisms in the estrogen metabolism pathway might be involved in the risk of prostate carcinoma development. We evaluated the association between genetic polymorphisms in estrogen receptor alpha (ESR1) and catechol-O-methyltransferase (COMT) genes and the risk of developing familial prostate carcinoma. MATERIALS AND METHODS: In this study, 34 cases with prostate carcinoma whose first-degree relatives had prostate carcinoma and 30 healthy age-matched male controls were enrolled. The genotypes of ESR1 and COMT genes were analyzed employing polymerase chain reaction-restriction fragment length polymorphism method. 34 cases with prostate carcinoma, whose first degree relatives had prostate carcinoma and 14 age-matched male controls were enrolled to analyze the genotype of these two genes. RESULTS: Among control patients, the ESR1 PvuII genotypes of C/C, C/T and T/T were observed in 37%, 26% and 37%, respectively, whereas the C/C, C/T and T/T genotypes were observed in 18%, 41% and 41% of case patients, respectively. Among controls, the ESR1 PvuII allele frequencies of C and T were equally observed, whereas the C and T allele frequencies were observed in 38% and 62% of patients, respectively. Among ESR1 PvuII genotypes there were not any significant difference in terms of genotype (P = 0.199) and allele (P = 0.181) frequencies. Among controls, the ESR1 XbaI genotypes of G/G, G/A and A/A were observed in 33%, 37% and 33%, respectively, whereas the G/G, G/A and A/A genotypes were observed in 12%, 47% and 41% of patients, respectively. Among controls, the ESR1 XbaI allele frequencies of A and G were observed equally, respectively, whereas the A and G frequencies were observed in 65% and 35% of patients, respectively. Among ESR1 Χ baI, there was not any significant difference in terms of genotype (P = 0.111) and allele (P = 0.093) frequencies. But the C/C genotype of the PvuII site and G/G genotype of the XbaI site in the ESR1 gene were associated significantly with the risk of developing prostate carcinoma. The G/G, G/A and A/A genotypes of the COMT gene were observed in 50%, 29% and 21% of control patients and in 53%, 21% and 26% of case patients, respectively. The A and G allele frequencies of the COMT gene were observed in 36.7%, 63.3% of control patients and in 36.8%, 63.2% of case patients, respectively. In COMT gene, there was not any significant difference in terms of genotype (P = 0.843) and allele (P = 0.991) frequencies. But the G/A genotype of the COMT gene had a weak tendency toward increased risk. CONCLUSION: Polymorphisms of ESR1 gene in the estrogen metabolism pathway were associated significantly with familial prostate carcinoma risk. Single nucleotide polymorphisms of low-penetrance genes are targets for understanding the genetic susceptibility of familial prostate carcinoma.

10.
Genet Test Mol Biomarkers ; 15(10): 701-7, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21699408

RESUMO

AIM: The purpose of this article was to evaluate the reliability of maternal serum triple marker screening of alpha-fetoprotein, human chorionic gonadotropin, and unconjugated estriol for the prenatal diagnosis of fetal chromosomal abnormalities in Turkish pregnant women. METHOD: Medical records were used to analyze indications of amniocentesis and quantitative fluorescent-polymerase chain reaction. Anomaly screening was performed for all patients between 13 and 22 weeks of pregnancy. A total of 1725 pregnancies with chromosomal abnormality risk according to triple test screening were accepted for fetal chromosome analysis and quantitative fluorescent-polymerase chain reaction. RESULTS: Chromosomal aberrations were observed in 56 (3.2%) cases. About 44.6% of the abnormalities detected were numerical aberrations; however, 55.3% of the abnormalities were structural aberrations. Abnormalities detected were inversion of chromosome 9 in 20 cases, trisomy 21 in 14 cases, 46,XX/47,XX, +21 in 1 case, trisomy 18 in 2 cases, trisomy 13 in 1 case, 47,XXY, in 1 case, 45,X, in 1 case, structural abnormalities in 12 cases, and mosaic or tetraploidy in 6 cases. CONCLUSION: Second trimester triple test is an effective screening tool for detecting fetal Down syndrome in Turkish women.


Assuntos
Aberrações Cromossômicas , Análise Citogenética/métodos , Doenças Fetais/diagnóstico , Diagnóstico Pré-Natal/métodos , Adolescente , Adulto , Feminino , Doenças Fetais/genética , Humanos , Recém-Nascido , Masculino , Gravidez , Reprodutibilidade dos Testes , Soro/metabolismo , Turquia , Adulto Jovem
11.
Genet Test Mol Biomarkers ; 13(1): 73-7, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19309277

RESUMO

AIM: To investigate parental origins and cell stage errors of a double nondisjunction in a fetus. METHOD: For the determination of the most common chromosome anomalies, quantitative fluorescent polymerase chain reaction method using short tandem repeat (STR) DNA markers was applied to a fetus with abnormal ultrasonographic findings. Parental origin and cell stage errors of the trisomies were inferred by comparing the inherited STR alleles. Conventional cytogenetic technique was also applied for the confirmation of the aneuploidies. RESULTS: A double nondisjunction including chromosomes 21 and X (48,XXX,+21) was detected prenatally in the fetus. The origin of both chromosomes was maternal, and the errors were in meiosis I for 21 and meiosis II for X. Molecular results were concordant with cytogenetic results. CONCLUSION: Molecular techniques could be useful for the pre- and postnatal diagnosis of the common aneuploidies and determining its parental origin. This kind of study will improve knowledge about the mechanisms of nondisjunction and enable appropriate and rapid genetic counseling.


Assuntos
Não Disjunção Genética , Reação em Cadeia da Polimerase/métodos , Diagnóstico Pré-Natal/métodos , Adulto , Aneuploidia , Cromossomos Humanos Par 21/genética , Cromossomos Humanos X/genética , Síndrome de Down/diagnóstico , Síndrome de Down/genética , Feminino , Humanos , Cariotipagem , Masculino , Meiose/genética , Repetições de Microssatélites , Gravidez , Trissomia/diagnóstico , Trissomia/genética
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