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1.
J Neuroradiol ; 49(1): 9-16, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34023361

RESUMO

INTRODUCTION: In patients with ulnar neuropathy at the elbow (UNE) the precise determination of the site of lesion is important for subsequent differential diagnostic considerations and therapeutic management. Due to a paucity of comparable data, to better define the role of different diagnostic tests, we performed the first prospective study comparing the diagnostic accuracy of short segment nerve stimulation, nerve ultrasonography, MR neurography (MRN), and diffusion tensor imaging (DTI) in patients with UNE. METHODS: UNE was clinically diagnosed in 17 patients with 18 affected elbows. For all 18 affected elbows in patients and 20 elbows in 10 healthy volunteers, measurements of all different diagnostic tests were performed at six anatomical positions across the elbow with measuring points from distal (D4) to proximal (P6) in relation to the medial epicondyle (P0). Additional qualitative assessment regarding structural changes of surrounding nerve anatomy was conducted. RESULTS: The difference between affected arms of patients and healthy control arms were most frequently the largest at measure intervals D2 to P0 and P0 to P2 for electrophysiological testing, or measure points P0 and P2 for all other devices, respectively. At both levels P0 and at P2, T2 contrast-to-noise ratio (CNR) of MRN and mean diffusivity (MD) of DTI-based MRN showed best accuracies. DISCUSSION: This study revealed differences in diagnostic performance of tests concerning a specific location of UNE, with better results for T2 contrast to noise ratio (CNR) in MRN and mean diffusivity of DTI-based MRN. Additional testing with MRN and nerve ultrasonography is recommended to uncover anatomical changes.


Assuntos
Cotovelo , Neuropatias Ulnares , Imagem de Tensor de Difusão , Cotovelo/diagnóstico por imagem , Eletrodiagnóstico , Humanos , Condução Nervosa , Estudos Prospectivos , Nervo Ulnar , Neuropatias Ulnares/diagnóstico por imagem
2.
J Sep Sci ; 40(11): 2488-2497, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28371325

RESUMO

Capillary electrophoresis analysis of transferrin in human serum is used to assess genetic variants after desialylation with neuraminidase and iron saturation to reduce the complexity of the transferrin pattern and thus facilitate the recognition of transferrin polymorphisms. Asialo-transferrin forms are analyzed by capillary zone electrophoresis using assay conditions as for the monitoring of carbohydrate-deficient transferrin or by capillary isoelectric focusing in a pH 5-8 gradient which requires immunoextraction of transferrin prior to analysis. With the carrier ampholytes used, peaks for iron saturated and iron depleted transferrin are monitored which indicates complexation of iron ions by carrier ampholytes. For BC, CD, and BD genetic variants, the expected peaks for B, C, and D forms of transferrin were detected with both methods. Monitoring of CC patterns revealed three cases, namely those producing double peaks in both methods, a double peak in capillary isoelectric focusing only and a double peak in capillary zone electrophoresis only. For all samples analyzed, data obtained by capillary isoelectric focusing could be confirmed with gel isoelectric focusing. The two capillary electrophoresis methods are shown to represent effective tools to assess unusual transferrin patterns, including genetic variants with dissimilar abundances of the two forms.


Assuntos
Eletroforese Capilar , Focalização Isoelétrica , Transferrina/genética , Misturas Anfolíticas , Variação Genética , Humanos , Soro/química , Transferrina/análise
3.
Addict Biol ; 20(3): 570-9, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-24720731

RESUMO

The compulsion to seek and use heroin is frequently driven by stress and craving during drug-cue exposure. Although previous neuroimaging studies have indicated that craving is mediated by increased prefrontal cortex activity, it remains unknown how heroin administration modulates the prefrontal cortex response. This study examines the acute effects of heroin on brain function in heroin-maintained patients. Using a crossover, double-blind, placebo-controlled design, 27 heroin-maintained patients performed functional magnetic resonance imaging 20 minutes after the administration of heroin or placebo (saline) while drug-related and neutral stimuli were presented. Images were processed and analysed with statistical parametric mapping. Plasma concentrations of heroin and its main metabolites were assessed using high-performance liquid chromatography. Region of interest analyses showed a drug-related cue-associated blood-oxygen-level-dependent activation in the orbitofrontal cortex (OFC) in heroin-dependent patients during both treatment conditions (heroin and placebo). This activation of the OFC was significantly higher after heroin than after placebo administration. These findings may indicate the importance of OFC activity for impulse control and decision-making after regular heroin administration and may emphasize the benefit of the heroin-assisted treatment in heroin dependence.


Assuntos
Dependência de Heroína/fisiopatologia , Heroína/farmacologia , Entorpecentes/farmacologia , Córtex Pré-Frontal/efeitos dos fármacos , Adulto , Encefalopatias/patologia , Encefalopatias/fisiopatologia , Fissura/efeitos dos fármacos , Sinais (Psicologia) , Feminino , Substância Cinzenta/efeitos dos fármacos , Substância Cinzenta/patologia , Heroína/administração & dosagem , Heroína/farmacocinética , Dependência de Heroína/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Entorpecentes/administração & dosagem , Entorpecentes/farmacocinética , Testes Neuropsicológicos , Tamanho do Órgão , Córtex Pré-Frontal/patologia
4.
Int J Mol Sci ; 16(4): 7057-76, 2015 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-25826533

RESUMO

The endocannabinoid (EC) system is implicated in many chronic liver diseases, including hepatitis C viral (HCV) infection. Cannabis consumption is associated with fibrosis progression in patients with chronic hepatitis C (CHC), however, the role of ECs in the development of CHC has never been explored. To study this question, anandamide (AEA) and 2-arachidonoyl glycerol (2-AG) were quantified in samples of HCV patients and healthy controls by gas and liquid chromatography mass spectrometry. Fatty acid amide hydrolase (FAAH) and monoaclyglycerol lipase (MAGL) activity was assessed by [3H]AEA and [3H]2-AG hydrolysis, respectively. Gene expression and cytokine release were assayed by TaqMan PCR and ELISpot, respectively. AEA and 2-AG levels were increased in plasma of HCV patients, but not in liver tissues. Hepatic FAAH and MAGL activity was not changed. In peripheral blood mononuclear cells (PBMC), ECs inhibited IFN-γ, TNF-α, and IL-2 secretion. Inhibition of IL-2 by endogenous AEA was stronger in PBMC from HCV patients. In hepatocytes, 2-AG induced the expression of IL-6, -17A, -32 and COX-2, and enhanced activation of hepatic stellate cells (HSC) co-cultivated with PBMC from subjects with CHC. In conclusion, ECs are increased in plasma of patients with CHC and might reveal immunosuppressive and profibrogenic effects.


Assuntos
Ácidos Araquidônicos/metabolismo , Endocanabinoides/metabolismo , Glicerídeos/metabolismo , Células Estreladas do Fígado/patologia , Hepatite C Crônica/imunologia , Hepatite C Crônica/patologia , Alcamidas Poli-Insaturadas/metabolismo , Adulto , Amidoidrolases/metabolismo , Ácidos Araquidônicos/sangue , Células Cultivadas , Citocinas/metabolismo , Endocanabinoides/sangue , Feminino , Glicerídeos/sangue , Células Estreladas do Fígado/metabolismo , Hepatite C Crônica/enzimologia , Humanos , Imunidade Celular , Masculino , Pessoa de Meia-Idade , Monoacilglicerol Lipases/metabolismo , Alcamidas Poli-Insaturadas/sangue
5.
J Sep Sci ; 37(13): 1663-70, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24737700

RESUMO

High-resolution capillary zone electrophoresis in the routine arena with stringent quality assurance is employed for the determination of carbohydrate-deficient transferrin in human serum. The assay comprises mixing of human serum with a Fe(III) -containing solution prior to analysis of the iron-saturated mixture in a dynamically double-coated capillary using a commercial buffer at alkaline pH. In contrast to other assays, it provides sufficient resolution for proper recognition of genetic transferrin variants. Analysis of 7290 patient sera revealed 166 isoform patterns that could be assigned to genetic variants, namely, 109 BC, 53 CD, one BD and three CC variants. Several subtypes of transferrin D can be distinguished as they have large enough differences in pI values. Subtypes of transferrin C and B cannot be resolved. However, analysis of the detection time ratios of tetrasialo isoforms of transferrin BC and transferrin CD variants revealed multimodal frequency histograms, indicating the presence of subtypes of transferrin C, B and D. The data gathered over 11 years demonstrate the robustness of the high-resolution capillary zone electrophoresis assay. This is the first account of a capillary zone electrophoresis based carbohydrate-deficient transferrin assay with a broad overview on transferrin isoform patterns associated with genetic transferrin variants.


Assuntos
Eletroforese Capilar/métodos , Variação Genética , Soro/química , Transferrina/genética , Humanos , Isoformas de Proteínas/sangue , Isoformas de Proteínas/genética , Transferrina/análise
6.
Front Psychol ; 15: 1252277, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38487661

RESUMO

Sensory processing is often altered in individuals with autism; thus, it is essential to develop reliable measurement tools to assess sensory perception. The Sensory Perception Quotient (SPQ) quantifies basic sensory sensitivities in adults via self-report. Adopting an expert by experience perspective, this study aimed to evaluate a German translation of the SPQ for its use in clinical and research applications, especially for autistic adults. 108 adults (n = 54 autistic) completed the German SPQ in an online assessment. A 92-item and a 35-item version of the German SPQ were analyzed for group differences and internal consistency. Our results show that adults with autism reported greater sensory sensitivity compared to non-autistic adults. Results further suggest good to excellent internal consistency for the 95-item and 35-item SPQ translations. This finding was supported by the correlative relationship between sensory sensitivity and autistic traits. These findings confirm the reliability of our SPQ translation, making it a suitable German assessment tool for basic sensory sensitivity in autistic adults.

7.
Electrophoresis ; 34(11): 1563-71, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23512316

RESUMO

The performance of high-resolution CZE for determination of carbohydrate-deficient transferrin (CDT) in human serum based on internal and external quality data gathered over a 10-year period is reported. The assay comprises mixing of serum with a Fe(III) ion-containing solution prior to analysis of the iron saturated mixture in a dynamically double-coated capillary using a commercial buffer at alkaline pH. CDT values obtained with a human serum of a healthy individual and commercial quality control sera are shown to vary less than 10%. Values of a control from a specific lot were found to slowly decrease as function of time (less than 10% per year). Furthermore, due to unknown reasons, gradual changes in the monitored pattern around pentasialo-transferrin were detected, which limit the use of commercial control sera of the same lot to less than 2 years. Analysis of external quality control sera revealed correct classification of the samples over the entire 10-year period. Data obtained compare well with those of HPLC and CZE assays of other laboratories. The data gathered over a 10-year period demonstrate the robustness of the high-resolution CZE assay. This is the first account of a CZE-based CDT assay with complete internal and external quality assessment over an extended time period.


Assuntos
Eletroforese Capilar/métodos , Transferrina/análogos & derivados , Eletroforese Capilar/normas , Humanos , Controle de Qualidade , Padrões de Referência , Sensibilidade e Especificidade , Transferrina/análise
8.
J Clin Psychopharmacol ; 33(2): 193-8, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23422375

RESUMO

Heroin dependence is associated with a stressful environment and with dysfunction of the hypothalamic-pituitary-adrenal (HPA) axis. The present study examined the acute effects of intravenous heroin versus placebo on the HPA axis response in heroin-dependent patients. Twenty-eight heroin-dependent patients in heroin-assisted treatment and 20 age- and sex-matched healthy participants were included in a controlled trial in which patients were twice administered heroin or saline in a crossover design, and healthy controls were only administered saline. The HPA axis response was measured by adrenocorticotropic hormone (ACTH) levels and by cortisol levels in serum and saliva before and 20 and 60 minutes after substance administration. Craving, withdrawal, and anxiety levels were measured before and 60 minutes after substance application. Plasma concentrations of heroin and its main metabolites were assessed using high-performance liquid chromatography. Heroin administration reduces craving, withdrawal, and anxiety levels and leads to significant decreases in ACTH and cortisol concentrations (P < 0.01). After heroin administration, cortisol concentrations did not differ from healthy controls, and ACTH levels were significantly lower (P < 0.01). In contrast, when patients receive saline, all hormone levels were significantly higher in patients than in healthy controls (P < 0.01). Heroin-dependent patients showed a normalized HPA axis response compared to healthy controls when they receive their regular heroin dose. These findings indicate that regular opioid administration protects addicts from stress and underscore the clinical significance of heroin-assisted treatment for heroin-dependent patients.


Assuntos
Dependência de Heroína/fisiopatologia , Heroína/farmacologia , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Hormônio Adrenocorticotrópico/metabolismo , Adulto , Estudos de Casos e Controles , Cromatografia Líquida de Alta Pressão , Estudos Cross-Over , Método Duplo-Cego , Feminino , Heroína/administração & dosagem , Heroína/farmacocinética , Humanos , Hidrocortisona/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Masculino , Pessoa de Meia-Idade , Sistema Hipófise-Suprarrenal/metabolismo , Abuso de Substâncias por Via Intravenosa , Adulto Jovem
9.
Mass Spectrom Rev ; 29(3): 503-21, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19890938

RESUMO

Radiation metabolomics can be defined as the global profiling of biological fluids to uncover latent, endogenous small molecules whose concentrations change in a dose-response manner following exposure to ionizing radiation. In response to the potential threat of nuclear or radiological terrorism, the Center for High-Throughput Minimally Invasive Radiation Biodosimetry was established to develop field-deployable biodosimeters based, in part, on rapid analysis by mass spectrometry of readily and easily obtainable biofluids. In this review, we briefly summarize radiation biology and key events related to actual and potential nuclear disasters, discuss the important contributions the field of mass spectrometry has made to the field of radiation metabolomics, and summarize current discovery efforts to use mass spectrometry-based metabolomics to identify dose-responsive urinary constituents, and ultimately to build and deploy a noninvasive high-throughput biodosimeter.


Assuntos
Espectrometria de Massas/métodos , Metabolômica , Lesões por Radiação/prevenção & controle , Lesões por Radiação/terapia , Biomarcadores , Biologia Computacional , Relação Dose-Resposta à Radiação , Humanos , Guerra Nuclear , Liberação Nociva de Radioativos , Terrorismo
10.
Radiat Res ; 172(2): 198-212, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19630524

RESUMO

Abstract Radiation metabolomics employing mass spectral technologies represents a plausible means of high-throughput minimally invasive radiation biodosimetry. A simplified metabolomics protocol is described that employs ubiquitous gas chromatography-mass spectrometry and open source software including random forests machine learning algorithm to uncover latent biomarkers of 3 Gy gamma radiation in rats. Urine was collected from six male Wistar rats and six sham-irradiated controls for 7 days, 4 prior to irradiation and 3 after irradiation. Water and food consumption, urine volume, body weight, and sodium, potassium, calcium, chloride, phosphate and urea excretion showed major effects from exposure to gamma radiation. The metabolomics protocol uncovered several urinary metabolites that were significantly up-regulated (glyoxylate, threonate, thymine, uracil, p-cresol) and down-regulated (citrate, 2-oxoglutarate, adipate, pimelate, suberate, azelaate) as a result of radiation exposure. Thymine and uracil were shown to derive largely from thymidine and 2'-deoxyuridine, which are known radiation biomarkers in the mouse. The radiation metabolomic phenotype in rats appeared to derive from oxidative stress and effects on kidney function. Gas chromatography-mass spectrometry is a promising platform on which to develop the field of radiation metabolomics further and to assist in the design of instrumentation for use in detecting biological consequences of environmental radiation release.


Assuntos
Algoritmos , Inteligência Artificial , Biomarcadores/urina , Cromatografia Gasosa-Espectrometria de Massas/métodos , Metaboloma/efeitos da radiação , Urinálise/métodos , Irradiação Corporal Total , Animais , Raios gama , Masculino , Metaboloma/fisiologia , Ratos , Ratos Wistar , Software
11.
J Chromatogr A ; 1206(1): 33-40, 2008 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-18533168

RESUMO

Capillary zone electrophoresis (CZE) in fused-silica capillaries is an effective analytical approach for the separation and determination of the transferrin (Tf) isoforms and thus carbohydrate-deficient transferrin (CDT) in human serum. Sera of patients with progressed liver cirrhosis are prone to interferences in the beta region which prevent the proper determination of CDT by CZE without additional sample preparation. Efforts to identify, reduce or even eliminate these interferences have been undertaken. Data obtained by ultrafiltration, affinity subtraction procedures using protein A, protein L and antibodies against immunoglobulins or Tf, and immunopurification of Tf suggest that the interferences in the patient sera are caused by increased levels of IgA and IgM and are best eliminated by immunopurification. Avian IgY antibody spin column immunocapture of serum Tf followed by CZE analysis of the stripped and concentrated fraction is shown to provide an attractive approach for CDT monitoring in sera with beta region interferences.


Assuntos
Eletroforese Capilar/métodos , Imunoglobulinas/sangue , Cirrose Hepática/sangue , Transferrina/análogos & derivados , Humanos , Espectrofotometria Ultravioleta/métodos , Transferrina/análise , Ultrafiltração
12.
Med Cannabis Cannabinoids ; 1(1): 9-18, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34676317

RESUMO

BACKGROUND: The endocannabinoids anandamide (N-arachidonoyl ethanolamide [AEA]) and 2-arachidonoyl glycerol (2-AG) are involved in the regulation of neuronal, immune, metabolic, vascular, and reproductory functions. METHODS: The development and validation of an analytical method for the determination of AEA and 2-AG in human plasma based on liquid-liquid extraction and gas chromatography-mass spectrometry after silylation is described and (pre)-analytical pitfalls are identified. RESULTS: In contrast to 2-AG, AEA was unstable in whole blood and increased by a factor of 2.3 within 3 h on ice. AEA was stable in plasma on ice for 4 h while 2-AG tended to decrease. Excellent stability at room/ambient temperature was found for both derivatized compounds over 45 h. Furthermore, 3 freeze-thaw cycles revealed a complex pattern: endogenous AEA was stable in plasma but slightly increased in spiked samples (+12.8%), while endogenous 2-AG concentrations increased by 51% and declined by 24% in spiked samples. A long-term study over 4 weeks at -80°C showed that low endogenous AEA and spiked 2-AG concentrations were stable. However, spiked AEA tended to increase (+19%) and endogenous 2-AG significantly increased by 50% after 2 weeks. Food intake 2 h before blood collection showed no effect on AEA concentrations, whereas 2-AG increased significantly by a factor of 3. CONCLUSIONS: Overall, limited in vitro and/or in vivo/ex vivo chemical stability of endocannabinoids has to be taken into account.

14.
J Chromatogr A ; 1130(2): 272-80, 2006 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-16777120

RESUMO

Capillary zone electrophoresis (CZE) with a dynamic double coating based on the new CEofix reagents is shown to provide high-resolution separations of serum transferrin (Tf) isoforms, a prerequisite for the monitoring of unusual and complex Tf patterns, including those seen with genetic variants and disorders of glycosylation. A 50 microm I.D. fused-silica capillary of 60 cm total length, an applied voltage of 20 kV and a capillary temperature of 30 degrees C results in 15 min CZE runs of high assay precision and thus provides a robust approach for the determination of carbohydrate-deficient transferrin (CDT, sum of asialo-Tf and disialo-Tf in relation to total Tf) in human serum. Except for selected samples of patients with severe liver diseases and sera with high levels of paraproteins, interference-free Tf patterns are detected. Compared with the use of the previous CEofix reagents for CDT under the same instrumental conditions, the resolution between disialo-Tf and trisialo-Tf is significantly higher (1.7 versus 1.4). The CDT levels of reference and patient sera are comparable, suggesting that the new assay can be applied for screening and confirmation analyses. The high-resolution CZE assay represents an attractive alternative to HPLC and can be regarded as a candidate of a reference method for CDT.


Assuntos
Eletroforese Capilar/métodos , Transferrina/análogos & derivados , Humanos , Indicadores e Reagentes/química , Isoformas de Proteínas/análise , Isoformas de Proteínas/sangue , Reprodutibilidade dos Testes , Transferrina/análise
15.
PLoS One ; 11(1): e0147286, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26784441

RESUMO

Inhalation by vaporization is a promising application mode for cannabis in medicine. An in vitro validation of 5 commercial vaporizers was performed with THC-type and CBD-type cannabis. Gas chromatography/mass spectrometry was used to determine recoveries of total THC (THCtot) and total CBD (CBDtot) in the vapor. High-performance liquid chromatography with photodiode array detection was used for the quantitation of acidic cannabinoids in the residue and to calculate decarboxylation efficiencies. Recoveries of THCtot and CBDtot in the vapor of 4 electrically-driven vaporizers were 58.4 and 51.4%, 66.8 and 56.1%, 82.7 and 70.0% and 54.6 and 56.7% for Volcano Medic®, Plenty Vaporizer®, Arizer Solo® and DaVinci Vaporizer®, respectively. Decarboxylation efficiency was excellent for THC (≥ 97.3%) and CBD (≥ 94.6%). The gas-powered Vape-or-Smoke™ showed recoveries of THCtot and CBDtot in the vapor of 55.9 and 45.9%, respectively, and a decarboxylation efficiency of ≥ 87.7 for both cannabinoids. However, combustion of cannabis was observed with this device. Temperature-controlled, electrically-driven vaporizers efficiently decarboxylate inactive acidic cannabinoids and reliably release their corresponding neutral, active cannabinoids. Thus, they offer a promising application mode for the safe and efficient administration of medicinal cannabis.


Assuntos
Maconha Medicinal/análise , Nebulizadores e Vaporizadores , Administração por Inalação , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Maconha Medicinal/administração & dosagem
16.
Swiss Med Wkly ; 145: w14098, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25665070

RESUMO

OBJECTIVE: Regular checking of the fitness to drive of elderly car-license holders is required in some countries, and this will become increasingly important as more countries face aging populations. The present study investigated whether the analysis of saccadic eye movements could be used as a screening method for the assessment of driving ability. METHODS: Three different paradigms (prosaccades, antisaccades, and visuovisual interactive (VVI) saccades) were used to test saccadic eye movements in 144 participants split into four groups: elderly drivers who came to the attention of road authorities for suspected lack of fitness to drive, a group of elderly drivers who served as a comparison group, a group of neurology patients with established brain lesion diagnoses, and a young comparison group. The group of elderly drivers with suspected deficits in driving skills also underwent a medical examination and a practical on-road driving test. The results of the saccadic eye tests of the different groups were compared. RESULTS: Antisaccade results indicated a strong link to driving behaviour: elderly drivers who were not fit to drive exhibited a poor performance on the antisaccade task and the performance in the VVI task was also clearly poorer in this group. CONCLUSIONS: Testing saccadic eye movements appears to be a promising and efficient method for screening large numbers of people such as elderly drivers. This study indicated a link between antisaccade performance and the ability to drive. Hence, measuring saccadic eye movements should be considered as a tool for screening the fitness to drive.


Assuntos
Aptidão/fisiologia , Exame para Habilitação de Motoristas , Condução de Veículo/psicologia , Movimentos Sacádicos/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Suíça
17.
J Chromatogr A ; 1013(1-2): 131-47, 2003 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-14604115

RESUMO

Capillary zone electrophoresis (CZE) with a dynamic double coating permits the simultaneous, individual, quantitative determination of transferrin (Tf) isoforms in human serum and thus carbohydrate-deficient transferrin (CDT), the most specific marker available today for the detection of chronic, excessive alcohol intake. CZE of serum Tf was carefully evaluated using the P/ACE MDQ with fused-silica capillaries of 50 microm I.D. and 60.2 cm total length, the CEofix CDT kit and the instrumental conditions recommended by the kit manufacturer. The precision performance assessed over a 20-day period according to the internationally accepted NCCLS EP5-A guidelines revealed the CZE assay as being highly reproducible with within-run and total precision being dependent on the Tf isoform level and RSD values ranging between 2.2 and 17.6%. Inter-day RSD values for asialo-Tf were noted to be between 9.8 and 11.5% and for disialo-Tf between 3.8 and 8.6%, whereas those for CDT levels of 0.87 and 4.31% of total Tf were determined to be 8.6 and 3.4%, respectively. The RSD values for trisialo-Tf, tetrasialo-Tf, pentasialo-Tf and hexasialo-Tf were found to be between 0.4 and 4.1%. Tf patterns are recognized and identified via detection times of Tf isoforms (intra-day and inter-day RSD values < 1.0% and < 1.7%, respectively), immunosubtraction of Tf and enzymatic sequential cleavage of sialic acid residues. Furthermore, heterozygous Tf BC and Tf CD variants are assigned via spiking with a known mixture of Tf isoforms (e.g. the serum of a healthy Tf C homozygote). Among the non-Tf peaks monitored, the CRP peak detected shortly before disialo-Tf was identified by immunosubtraction and peak magnitudes were found to correlate well with immunochemically determined CRP serum levels. The CZE assay with dynamic double coating could thereby be shown to be sensitive enough to determine elevated CRP levels in human serum. Furthermore, unusual peaks in the gamma-region were identified by customary serum protein CZE, immunosubtraction CZE and immunofixation.


Assuntos
Eletroforese Capilar/métodos , Transferrina/análogos & derivados , Transferrina/metabolismo , Humanos , Reprodutibilidade dos Testes
18.
J Chromatogr A ; 979(1-2): 43-57, 2002 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-12498232

RESUMO

Serum transferrin (Tf) comprises several isoforms with up to two complex oligosaccharide chains containing zero to eight sialic acid residues and neutral sugars. The major glycoform, known as tetrasialo-Tf, contains four sialic acid residues and accounts for about 80% of whole Tf in human serum. Carbohydrate-deficient transferrin (CDT) encompasses isoforms that are deficient in carbohydrate chains and consequently in sialic acid residues (including asialo-, monosialo- and disialo-Tf) and is a well known marker for chronic alcohol abuse. Recently capillary zone electrophoresis (CZE) has been reported as a tool extremely effective for the simultaneous, individual, quantitative determination of CDT isoforms. Three CZE methods that feature different dynamic capillary coatings were evaluated and optimized for CDT determination in human serum of alcohol abusers and control subjects. CZE separation was performed in alkaline borate buffers after serum sample saturation with iron, electropherograms were detected at 200 nm, data were evaluated as % area of disialo-Tf in relation to tetrasialo-Tf and peak identification was accomplished via relative migration times to tetrasialo-Tf, immunosubtraction and enzymatic sequential cleavage of sialic acid residues. Dynamic capillary coatings with diaminobutane, spermine and a double coating produced by commercially available proprietary agents were investigated and found to be suitable for determination of CDT in human serum. For all three approaches, best results were obtained in 50 microm I.D. fused-silica capillaries of 50 cm effective length and a capillary cartridge temperature of 20-25 degrees C. Using 3 mM 1,4-diaminobutane or 0.02 mM spermine in a borate-based running buffer of pH 8.3 provided data of remarkable similarity with resolution of di-, tri-, tetra- and pentasialo-Tf within 15-18 min. With the double coating, asialo-Tf and Tf isoforms with two to six sialic acid residues were baseline separated. Compared to the two amine-based procedures, the run times were found to be somewhat shorter, the detector signals higher, the applied power level significantly lower and the reproducibility better.


Assuntos
Eletroforese Capilar/métodos , Transferrina/análogos & derivados , Transferrina/análise , Sangue , Humanos , Espectrofotometria Ultravioleta , Espermina/análise
19.
Iran J Pharm Res ; 13(4): 1425-30, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25587333

RESUMO

Phytochemical investigation of a dichloromethane-methanol (1:1) extract of the fruit pericarp of Omphalocarpum procerum which exhibited antiplasmodial activity during preliminary screening led to the isolation of the new fatty ester triterpenoid 3ß-hexadecanoyloxy-28-hydroxyolean-12-en-11-one (1), together with five known compounds 2-6. The structure of the new compound as well as those of the known compounds was established by means of spectroscopic methods and by comparison with previously reported data. Compounds 1- 4 were evaluated in-vitro for their cytotoxicity against L6 cell lines and antiprotozoal activities against Plasmodium falciparum, Leishmania donovani, Trypanosoma brucei rhodesiense and Trypanosoma cruzi (species responsible for human malaria, visceral leishmaniasis, African trypanosomiasis and Chagas disease, respectively). The tested compounds showed weak to moderate antiprotozoal activity and, no significant effect was detected regarding their cytotoxic potency.

20.
J Forensic Leg Med ; 20(7): 870-4, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24112339

RESUMO

OBJECTIVES: The influence of low-dose alcohol intake on reflexive visually guided saccades was investigated. METHODS: 40 healthy human subjects were orally given alcohol resulting in low-dose alcohol concentration (less than 0.8‰) blood alcohol concentration. Before and after exposure, horizontal saccadic eye movements were recorded at several points in time. The recordings were evaluated with regard to accuracy of the eye movements, latency, the peak eye velocity and the time constant that characterizes the main sequence. The results were compared to recordings from a reference group. RESULTS: It was found that the saccadic eye movement was clearly altered by low-dose alcohol intake. However, its characteristics were not unambiguously pathological when compared to the reference group, even though the subjects reported a moderate to strong effect of alcohol and there were clear signs of inebriation. CONCLUSIONS: The findings render the evaluation of saccades unsuitable as a simple test for the detection of low-dose alcohol intake.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Depressores do Sistema Nervoso Central/administração & dosagem , Etanol/administração & dosagem , Movimentos Sacádicos/efeitos dos fármacos , Administração Oral , Adolescente , Adulto , Depressores do Sistema Nervoso Central/efeitos adversos , Depressores do Sistema Nervoso Central/sangue , Relação Dose-Resposta a Droga , Etanol/efeitos adversos , Etanol/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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