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1.
Molecules ; 27(7)2022 Mar 27.
Article in English | MEDLINE | ID: mdl-35408563

ABSTRACT

Spatially resolved information on corrosion reactions operating at the cut edges of coated metals can be obtained using microelectrochemical scanning techniques using a suitable selection of operation modes and scanning probes. The scanning vibrating electrode technique (SVET) provides current density maps with a spatial resolution of the order of the dimensions of the sample, which allows the temporal evolution of the corrosion reactions to be followed over time. This leads to the identification and localization of cathodic and anodic sites, although the technique lacks chemical specificity for the unequivocal identification of the reactive species. The application of scanning electrochemical microscopy (SECM) was previously limited to image cathodic reaction sites, either due to oxygen consumption in the amperometric operation or by the alkalinisation of the electrolyte in potentiometric operation. However, it is shown that anodic sites can be effectively monitored using an ion-selective microelectrode (ISME) as a probe. The ISME probes detected differences in the local concentrations of Zn2+ and OH- ions from the cut edges of a complete coil coating system compared to the same system after the polymeric layers were removed. In this way, it has been shown that the inhibitor loading in the polymer layers effectively contributes to reducing the corrosion rates at the cut edge, thus helping to extend the useful life of the sacrificial galvanized layer bonded directly to the steel matrix. Additionally, these two probe configurations can be integrated into a multi-electrode tip for potentiometric operation to simultaneously monitor localized changes in pH values and metal ion dissolution in a single scan. Spatial and temporal distributions were further investigated using different rastering procedures, and the potential of constructing pseudomaps for 2D-imaging is described.

2.
Sensors (Basel) ; 21(15)2021 Jul 26.
Article in English | MEDLINE | ID: mdl-34372300

ABSTRACT

Diabetes mellitus represents one of the most widespread diseases in civilization nowadays. Since the costs for treating and diagnosing of diabetes represent several billions of dollars per year, a cheap, fast, and simple sensor for diabetes diagnosis is needed. Electrochemical insulin sensors can be considered as a novel approach for diabetes diagnosis. In this study, carbon electrode with electrodeposited NiO nanoparticles was selected as a suitable electrode material for insulin determination. The morphology and surface composition were studied by scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectroscopy, and X-ray photoelectron spectroscopy (XPS). For a better understanding of insulin determination on NiO-modified electrodes, the mechanism of electrochemical reaction and the kinetic parameters were studied. They were calculated from both voltammetric and amperometric measurements. The modified carbon electrode displayed a wide linear range from 600 nM to 10 µM, a low limit of detection of 19.6 nM, and a high sensitivity of 7.06 µA/µM. The electrodes were stable for 30 cycles and were able to detect insulin even in bovine blood serum. Additionally, the temperature stability of this electrode and its storage conditions were studied with appropriate outcomes. The above results show the high promise of this electrode for detecting insulin in clinical samples.


Subject(s)
Electrochemical Techniques , Nanoparticles , Animals , Cattle , Electrodes , Humans , Insulin , Limit of Detection , Nickel
3.
Ann Clin Microbiol Antimicrob ; 16(1): 31, 2017 Apr 14.
Article in English | MEDLINE | ID: mdl-28410611

ABSTRACT

BACKGROUND: Scedosporium apiospermum is an emerging opportunistic filamentous fungus, which is notorious for its high levels of antifungal-resistance. It is able to cause localized cutaneous or subcutaneous infections in both immunocompromised and immunocompetent persons, pulmonary infections in patients with predisposing pulmonary diseases and invasive mycoses in immunocompromised patients. Subcutaneous infections caused by this fungus frequently show chronic mycetomatous manifestation. CASE REPORT: We report the case of a 70-year-old immunocompromised man, who developed a fungal mycetomatous infection on his right leg. There was no history of trauma; the aetiological agent was identified by microscopic examination and ITS sequencing. This is the second reported case of S. apiospermum subcutaneous infections in Hungary, which was successfully treated by surgical excision and terbinafine treatment. After 7 months, the patient remained asymptomatic. Considering the antifungal susceptibility and increasing incidence of the fungus, Scedosporium related subcutaneous infections reported in the past quarter of century in European countries were also reviewed. CONCLUSIONS: Corticosteroid treatment represents a serious risk factor of S. apiospermum infections, especially if the patient get in touch with manure-enriched or polluted soil or water. Such infections have emerged several times in European countries in the past decades. The presented data suggest that besides the commonly applied voriconazole, terbinafine may be an alternative for the therapy of mycetomatous Scedosporium infections.


Subject(s)
Antifungal Agents/administration & dosage , Debridement , Leg/pathology , Mycetoma/diagnosis , Mycetoma/therapy , Naphthalenes/administration & dosage , Scedosporium/isolation & purification , Aged , Cluster Analysis , DNA, Fungal/chemistry , DNA, Fungal/genetics , DNA, Ribosomal Spacer/chemistry , DNA, Ribosomal Spacer/genetics , Dermatomycoses/diagnosis , Dermatomycoses/microbiology , Dermatomycoses/pathology , Dermatomycoses/therapy , Humans , Hungary , Immunocompromised Host , Male , Microscopy , Mycetoma/microbiology , Mycetoma/pathology , Phylogeny , Recurrence , Scedosporium/classification , Scedosporium/cytology , Scedosporium/genetics , Sequence Analysis, DNA , Terbinafine , Treatment Outcome
4.
Data Brief ; 56: 110796, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39263235

ABSTRACT

Monographic processing of Avar Period (6-8th century) glass beads. Approx. 200 glass beads have been selected from 13 archaeological sites in current day Hungary as the representatives of typical Avar glass beads. The beads were analyzed with electron microprobe analyzer attached with wavelength dispersive X-ray spectrometer and/or energy dispersive X-ray spectrometer peripheries for 12-15 elements complemented with archaeological and color description. These beads provide insights primarily into the trade and interactions of the Avar population in the Carpathian Basin with other peoples. Through their analysis, we can learn about the economic systems associated with glass production and the connections between different regions. Furthermore, Avar Age glass beads offer valuable information about craftsmanship and artistic expression. Their diverse shapes, colors, and patterns showcase the skill and creativity of the artisans who made them, as well as hint at the production technology used. The purpose of data collection is to identify the raw materials and coloring agents used in bead production, detect potential chronological changes, internationally explore the identified production technology in terms of space and time, and outline the Avars' trade network, and provide reference for future research. This is the first ever published database of Avar Age glass beads.

5.
Orv Hetil ; 153(27): 1068-76, 2012 Jul 08.
Article in Hungarian | MEDLINE | ID: mdl-22759747

ABSTRACT

UNLABELLED: The objective of the research was to assess the health related quality of life and productivity of women with overactive bladder. METHODS: A cross-sectional survey was performed in 5 outpatient centers. General health status (EQ-5D), disease-specific quality of life (King's Health Questionnaire) and productivity (Work Productivity and Activity Impairment) were assessed. RESULTS: Sixty-one women with mean age of 57.7 (SD = 11.6) years have had symptoms for 6.6 (SD = 6.2) years and 57 (93%) had incontinence. The EQ-5D (mean 0.668, SD = 0.314) was not significantly lower than that of the average population (p>0.05). The impact of incontinence and physical limitation (mean 70.5 and 68.9, respectively) were significant, the King's Health Questionnaire-utility was 0.932 (SD = 0.029). Productivity scores of involved patients were: absenteeism 0.04% (SD = 0.11), presenteeism 43.64% (SD = 28.54), overall work impairment 40.97% (SD = 26.91), and other activities 47.72% (SD = 27.24). CONCLUSIONS: Applicability of the EQ-5D and King's Health Questionnaire as utility measures in overactive bladder deserve further research. Presenteeism should be considered in the evaluation of the therapy.


Subject(s)
Efficiency , Quality of Life , Urinary Bladder, Overactive/epidemiology , Urinary Bladder, Overactive/psychology , Absenteeism , Adult , Aged , Aged, 80 and over , Cross-Sectional Studies , Emotions , Female , Health Status , Humans , Hungary/epidemiology , Interpersonal Relations , Middle Aged , Severity of Illness Index , Sleep , Surveys and Questionnaires , Urinary Incontinence/epidemiology , Urinary Incontinence/psychology
6.
Orv Hetil ; 153(9): 323-9, 2012 Mar 04.
Article in Hungarian | MEDLINE | ID: mdl-22348847

ABSTRACT

Patients with diabetes are approximately 1.5 times more likely to experience cognitive decline than individuals without diabetes mellitus. Most of the data suggest that patients with diabetes have reduced performance in numerous domains of cognitive function. In patients with type 1 diabetes, specific and global deficits involving speed of psychomotor efficiency, information processing, mental flexibility, attention, and visual perception seem to be present, while in patients with type 2 diabetes an increase in memory deficits, a reduction in psychomotor speed, and reduced frontal lobe (executive) functions have been found. The complex pathophysiology of changes in the central nervous system in diabetes has not yet been fully elucidated. It is important to consider the patient's age at the onset of diabetes, the glycemic control status, and the presence of diabetic complications. Neurological consequences of diabetes appear parallel to those observed in the aging brain. Neuroimaging studies highlight several structural cerebral changes, cortical and subcortical atrophy, beside increased leukoaraiosis that occurs in association with diabetes. There is supporting evidence from many hypotheses to explain the pathophysiology of cognitive decline associated with diabetes. The main hypotheses pointing to the potential, implied mechanisms involve hyperglycemia, hypoglycemia, microvascular disease, insulin resistance, hyperinsulinism, hyperphosphorylation of tau protein, and amyloid-ß deposition.


Subject(s)
Brain/pathology , Cognition Disorders/etiology , Cognition , Diabetes Mellitus/pathology , Diabetes Mellitus/psychology , Higher Nervous Activity , Psychomotor Performance , Age of Onset , Animals , Attention , Brain/physiopathology , Cognition Disorders/pathology , Cognition Disorders/physiopathology , Diabetes Complications/pathology , Diabetes Complications/psychology , Diabetes Mellitus/metabolism , Diabetes Mellitus/physiopathology , Diabetes Mellitus, Type 1/psychology , Diabetes Mellitus, Type 2/psychology , Frontal Lobe/pathology , Hippocampus , Humans , Leukoaraiosis , Memory Disorders/etiology , Thinking
7.
World J Diabetes ; 13(10): 835-850, 2022 Oct 15.
Article in English | MEDLINE | ID: mdl-36312000

ABSTRACT

It has been 100 years since the first successful clinical use of insulin, yet it remains the only treatment option for type 1 diabetes mellitus (T1DM) patients. Advances in diabetes care, such as insulin analogue therapies and new devices, including continuous glucose monitoring with continuous subcutaneous insulin infusion have improved the quality of life of patients but have no impact on the pathogenesis of the disease. They do not eliminate long-term complications and require several lifestyle sacrifices. A more ideal future therapy for T1DM, instead of supplementing the insufficient hormone production (a consequence of ß-cell destruction), would also aim to stop or slow down the destructive autoimmune process. The discovery of the autoimmune nature of type 1 diabetes mellitus has presented several targets by which disease progression may be altered. The goal of disease-modifying therapies is to target autoimmune mechanisms and prevent ß-cell destruction. T1DM patients with better ß-cell function have better glycemic control, reduced incidence of long-term complications and hypoglycemic episodes. Unfortunately, at the time symptomatic T1DM is diagnosed, most of the insulin secreting ß cells are usually lost. Therefore, to maximize the salvageable ß-cell mass by disease-modifying therapies, detecting autoimmune markers in an early, optimally presymptomatic phase of T1DM is of great importance. Disease-modifying therapies, such as immuno- and regenerative therapies are expected to take a relevant place in diabetology. The aim of this article was to provide a brief insight into the pathogenesis and course of T1DM and present the current state of disease-modifying therapeutic interventions that may impact future diabetes treatment.

8.
Blood Press ; 20(3): 134-9, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21133825

ABSTRACT

BACKGROUND: The aim of this study was to obtain epidemiological data and to determine the prevalence of adolescent hypertension implementing a blood pressure (BP) screening. METHODS: We performed a cross-sectional, population-based survey in a major Hungarian city (Debrecen, population 230,000). After a 10-min resting period, three consecutive BP measurements were taken. RESULTS: Complete records were obtained for 10,194 subjects (5163 boys and 5031 girls). The mean age was 16.6±1.0 years. BP for boys was higher than for girls (ΔBP(syst)=11 mmHg; ΔBP(diast)=2 mmHg, p<0.001). A significant decrease was observed in BP during the three consecutive measurements (time 1-3: ΔBP(syst)=4 mmHg; ΔBP(diast)=2.5 mmHg; p<0.001). Systolic and/or diastolic BP exceeded the age-, gender- and height-adjusted 90th percentile in 1614 (15.84%) adolescents. Following two lots of three extra measurements on 1461 subjects of this sub-sample, hypertension (systolic and/or diastolic BP exceeded the 95th percentile) was confirmed in 2.12% of the subjects (male: 2.27%, female: 1.97%). Considering there were individuals either already diagnosed with hypertension (n=19) or refusing further participation, the prevalence of hypertension was 2.53% in adolescents in the age range 15-18 years. CONCLUSION: Our population-based study was the first to determine the point-prevalence of adolescent hypertension in Central-Eastern Europe. Identifying and following-up cases of confirmed hypertension is inevitable to prevent or delay the manifestations of target organ damage and reduce hypertension-related mortality.


Subject(s)
Adolescent , Blood Pressure/physiology , Hypertension/diagnosis , Hypertension/physiopathology , Cross-Sectional Studies , Diastole , Female , Humans , Hungary/epidemiology , Hypertension/epidemiology , Male , Prevalence , Sentinel Surveillance , Systole
9.
Orv Hetil ; 152(13): 498-504, 2011 Mar 27.
Article in Hungarian | MEDLINE | ID: mdl-21398210

ABSTRACT

Diabetes mellitus and depression are public health concerns of the present and, as predicted, also the future. The observation that depression is seen more frequently in diabetic patients compared to the non-diabetic population has been proven by several recent studies. The co-occurrence carries further risks for the affected patients, as depression in diabetics may affect sufficient treatment of diabetes and enhance the development of diabetic complications. These may further worsen depressive symptoms causing a vicious cycle in these patients. In the present paper authors discuss in detail the theoretic and practical issues of the complex two directional relationships between diabetes and depression. Their goal is to draw attention to depression as co-morbidity of diabetes that may interfere with the optimization of diabetic patient's carbohydrate metabolism. If sufficient glycaemic control is not achieved using routine clinical methods depression should be evaluated as a probable cause. If needed, depression should be treated to improve the medical outcomes and quality of life of diabetic patients.


Subject(s)
Antidepressive Agents/therapeutic use , Blood Glucose/metabolism , Depression/diagnosis , Depression/therapy , Diabetes Complications/psychology , Diabetes Complications/therapy , Diabetes Mellitus/psychology , Affect , Comorbidity , Depression/blood , Depression/complications , Depression/drug therapy , Depression/epidemiology , Depressive Disorder, Major/diagnosis , Depressive Disorder, Major/therapy , Diabetes Complications/blood , Diabetes Complications/diagnosis , Diabetes Complications/epidemiology , Diabetes Mellitus/blood , Diabetes Mellitus/diagnosis , Diabetes Mellitus/drug therapy , Humans
10.
ACS Appl Mater Interfaces ; 13(36): 43587-43596, 2021 Sep 15.
Article in English | MEDLINE | ID: mdl-34473486

ABSTRACT

Recently, the cytotoxic properties of galvanically coupled Ti-Mg particles have been shown in different cells. This cytotoxic effect has been attributed mainly to Mg due to its tendency to undergo activation when coupled with Ti, forming a galvanic cell consisting of an anode (Mg) and a cathode (Ti). However, the role of the Ti cathode has been ignored in explaining the cytotoxic effect of Ti-Mg particles due to its high resistance to corrosion. In this work, the role of titanium (Ti) in the cytotoxic mechanism of galvanically coupled Ti-Mg particles was examined. A model galvanic cell (MGC) was prepared to simulate the Mg-Ti particles. The electrochemical reactivity of the Ti sample and the pH change in it due to galvanic coupling with Mg were investigated using scanning electrochemical microscopy (SECM). It was observed that the Ti surface changed from passive to electrochemically active when coupled with Mg. Furthermore, after only 15 min of galvanic coupling with Mg, the pH in the electrolyte volume adjacent to the Ti surface increased to an alkaline pH value. The effects of the galvanic coupling of Ti and Mg, as well as those of the alkaline pH environment, on the viability of Hs27 fibroblast cells were investigated. It was shown that the viability of Hs27 cells significantly diminished when Mg and Ti were galvanically coupled compared to when the two metals were electrically disconnected. Thus, although Ti usually exhibited high corrosion resistance when exposed to physiological environments, an electrochemically active surface was observed when galvanically coupled with Mg, and this surface may participate in electron transfer reactions with chemical species in the neighboring environment; this participation resulted in the increased pH values above its surface and enhanced generation of reactive oxygen species. These features contributed to the development of cytotoxic effects by galvanically coupled Ti-Mg particles.


Subject(s)
Magnesium/toxicity , Titanium/toxicity , Cell Line , Cell Survival/drug effects , Humans , Hydrogen-Ion Concentration , Microscopy, Electrochemical, Scanning , Reactive Oxygen Species/metabolism
11.
Diabetes Metab Res Rev ; 26(8): 646-55, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20922819

ABSTRACT

BACKGROUND: Diabetes mellitus results in accelerated atherosclerosis. We evaluated preclinical, morphological and functional vascular changes in type 1 diabetes mellitus. METHODS: Diameter, intima-media thickness, intima-media cross-section area, and elasticity features (compliance, distensibility coefficient, circumferential strain, stiffness index, incremental elastic modulus) of the common carotid arteries and carotid-femoral pulse wave velocity were studied in 42 patients with type 1 diabetes mellitus without macroangiopathy, and 41 control subjects matched for sex, age and body mass index using an ultrasonographic vessel wall-movement tracking system and applanation tonometry. RESULTS: Significantly larger intima-media thickness (523 ± 55 versus 567 ± 89 µm, p < 0.01), intima-media cross-section area (11.60 ± 1.81 versus 13.08 ± 3.02 mm(2) , p < 0.01), SI (5.58 ± 1.24 versus 7.08 ± 2.69, p < 0.01) and pulse wave velocity (6.00 ± 0.82 versus 6.61 ± 1.56 m/s, p < 0.05) were found in type 1 diabetes mellitus patients compared to controls. When type 1 diabetes mellitus patients with short and long disease duration (≤ or > 10 years) were compared, diameter (6450 ± 433 versus 6847 ± 750 µm, p < 0.05), intima-media cross-section area (11.97 ± 1.98 versus 14.01 ± 3.43 mm, p < 0.05) and pulse wave velocity (5.90 ± 0.92 versus 7.20 ± 1.74 m/s, p < 0.01) differed significantly. When multivariate analyses were restricted to type 1 diabetes mellitus patients, age was an independent predictor of stiffness index and pulse wave velocity, the duration of diabetes mellitus of intima-media cross-section area and pulse wave velocity, systolic blood pressure of diameter and pulse wave velocity, and low-density lipoprotein-cholesterol of intima-media thickness, intima-media cross-section area and stiffness index. CONCLUSIONS: There are differences in the time course of evolution and in predictors of morphological and functional changes in arteries in type 1 diabetes mellitus.


Subject(s)
Arteries/pathology , Carotid Artery, Common/physiopathology , Diabetes Mellitus, Type 1/physiopathology , Adult , Blood Flow Velocity , Blood Pressure , Carotid Artery, Common/diagnostic imaging , Diabetes Mellitus, Type 1/blood , Diabetes Mellitus, Type 1/pathology , Female , Humans , Male , Pulsatile Flow/physiology , Tunica Intima/pathology , Tunica Media/pathology , Ultrasonography , Vascular Resistance
12.
Orv Hetil ; 151(22): 899-902, 2010 May 30.
Article in Hungarian | MEDLINE | ID: mdl-20478811

ABSTRACT

UNLABELLED: Dipeptidyl peptidase-4 (DPP-4) has an important role in the carbohydrate metabolism with the degradation of incretin hormones. AIM: We assessed the serum DPP-4 activity both in fasting and postprandial condition in patients with type 1-, type 2 diabetes and healthy controls. METHODS: Serum DPP-4 activities were determined at fasting sate and at 60 and 180 minutes after test meal. DPP-4 activity was measured by microplate-based kinetic assay in 41 type 1-, and in 87 type 2 diabetic patients and in 25 healthy volunteers. RESULTS: Serum DPP-4 activities were found significantly higher both in fasting and postprandial state in patients with type 1 diabetes than in type 2 and control subjects. No change in the enzyme activities was found after test meal. Correlation was neither detected between the fasting plasma glucose nor between the HbA(1C) and the DPP-4 values in any of the groups studied. CONCLUSIONS: RESULTS suggest that it is not the hyperglycemia, rather the type of diabetes which determinates the serum DPP-4 enzymatic activity. The exact background of this phenomenon is not yet clear, however, increased serum DPP-4 enzyme activity in type 1 diabetes mellitus may refer to pancreatic autoimmune process, concomitant autoimmune diseases, hormonal feed back mechanism, or even target organ damage.


Subject(s)
Diabetes Mellitus, Type 1/enzymology , Dipeptidyl Peptidase 4/blood , Adult , Aged , Biomarkers/blood , Blood Glucose/metabolism , Diabetes Mellitus, Type 1/blood , Diabetes Mellitus, Type 2/enzymology , Dipeptidyl Peptidase 4/metabolism , Female , Glucagon-Like Peptide 1/blood , Glycated Hemoglobin/metabolism , Humans , Male , Middle Aged
13.
BMC Med Genet ; 10: 79, 2009 Aug 19.
Article in English | MEDLINE | ID: mdl-19691832

ABSTRACT

BACKGROUND: Hypoxia inducible factor-1 alpha (HIF-1alpha) is a transcription factor that plays an important role in neo-vascularisation, embryonic pancreas beta-cell mass development, and beta cell protection. Recently a non synonymous single nucleotide polymorphism (g.C45035T SNP, rs11549465) of HIF-1alpha gene, resulting in the p.P582S amino acid change has been shown to be associated with type 2 diabetes (T2DM) in a Japanese population. Our aim was to replicate these findings on a Caucasian (Hungarian) population, as well as to study whether this genetic effect is restricted to T2DM or can be expanded to diabetes in general. METHODS: A large Caucasian sample (N = 890) was recruited including 370 T2DM, 166 T1DM and 354 healthy subjects. Genotyping was validated by two independent methods: a restriction fragment analysis (RFLP) and a real time PCR using TaqMan probes. An overestimation of heterozygotes by RFLP was observed as a consequence of a nearby SNP (rs34005929). Therefore genotyping results of the justified TaqMan system were accepted. The measured genotype distribution corresponded to Hardy-Weinberg equilibrium (P = 0.740) RESULTS: As the TT genotype was extremely rare in the population (0.6% in clinical sample and 2.5% in controls), the genotypes were grouped as T absent (CC) and T present (CT and TT). Genotype-wise analysis showed a significant increase of T present group in controls (24.0%) as compared to patients (16.8%, P = 0.008). This genetic effect was demonstrated in the separated samples of type 1 (15.1%, P = 0.020), and also in type 2 (17.6%, P = 0.032) diabetes. Allele-wise analysis gave identical results showing a higher frequency of the T allele in the control sample (13.3%) than in the clinical sample (8.7%, P = 0.002) with similar results in type 1 (7.8%, P = 0.010) and type 2 (9.1%, P = 0.011) diabetes. The odds ratio for diabetes (either type 1 or 2) was 1.56 in the presence of the C allele. CONCLUSION: We confirmed the protective effect of a rare genetic variant of HIF-1alpha gene against type 2 diabetes in a Caucasian sample. Moreover we demonstrated a genetic contribution of the same polymorphism in type 1 diabetes as well, supporting a possible overlap in pathomechanism for T2DM and a T1DM.


Subject(s)
Diabetes Mellitus, Type 1/genetics , Diabetes Mellitus, Type 2/genetics , Hypoxia-Inducible Factor 1, alpha Subunit/genetics , Adolescent , Adult , Aged , Alleles , Amplified Fragment Length Polymorphism Analysis , Cell Hypoxia , Cell Line, Tumor , Female , Genotype , Humans , Hungary , Male , Middle Aged , Polymorphism, Single Nucleotide , Transfection , White People/genetics , Young Adult
14.
Anal Biochem ; 393(1): 8-22, 2009 Oct 01.
Article in English | MEDLINE | ID: mdl-19524544

ABSTRACT

Amadori peptides were enriched using boronate affinity tips and measured by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF/MS). As demonstrated by electrochemical measurements, the tips show the highest binding efficiency for glucose at pH 8.2 employing ammonium chloride/ammonia buffer with ionic strength of 150 mM, exceeding taurine buffer at the same concentration. The bound constituents were released by sorbitol and formic acid. It was also demonstrated that elution with sorbitol at 1.2 M is superior to acidic media. Comparison of results was based on the numbers of detected peptides and their glycated sites. Using sorbitol for elution requires desalting prior to analysis. Therefore, three different sorbents were tested: fullerene-derivatized silica, ZipTip (C18), and C18 silica. Fullerene-derivatized silica and ZipTip showed the same performance regarding the numbers of glycated peptides, and sites were better than C18 silica. The elaborated off-line method was compared with liquid chromatography-tandem mass spectrometry (LC-MS/MS) measurements, by which considerable less modified peptides were detected. Affinity tips used under optimized conditions were tested for the analysis of human serum albumin (HSA) from sera of healthy and diabetic individuals. A peptide with a mass of 1783.9 Da could be detected only in samples of diabetic patients and, therefore, could be a very interesting biomarker candidate.


Subject(s)
Chromatography, Affinity/methods , Glycopeptides/chemistry , Glycopeptides/isolation & purification , Glycoproteins/chemistry , Peptides/isolation & purification , Boronic Acids/chemistry , Chromatography, Affinity/instrumentation , Humans , Molecular Structure , Peptides/chemistry , Ribonuclease, Pancreatic/analysis , Serum Albumin/analysis
15.
Anal Bioanal Chem ; 394(7): 1955-63, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19517100

ABSTRACT

The diffusion coefficient of glucose in different media is an important parameter in life sciences, as well as in biotechnology and microbiology. In this work a simple, fast method is proposed that is based on the electrochemical time of flight principle. In most of the earlier time of flight experiments performed, a constant flight distance was applied. In the present work a scanning electrochemical microscope (SECM) was applied as a measuring tool. With use of the SECM, the flying distance could be changed with high precision, making measurements with several flight distances more accurate and reliable values could be obtained for solutions as well as for gels. The conventional voltammetric methods are not applicable for glucose detection. In our work electrocatalytic copper oxide coated copper microelectrodes and micro-sized amperometric enzyme sensors were used as detectors, while microdroplet-ejecting pneumatically driven micropipettes were used as a source.


Subject(s)
Gels/chemistry , Glucose/analysis , Biosensing Techniques/instrumentation , Biosensing Techniques/methods , Catalysis , Copper/chemistry , Diffusion , Electrochemistry , Flow Injection Analysis/instrumentation , Flow Injection Analysis/methods , Microelectrodes , Particle Size , Sensitivity and Specificity , Solutions , Surface Properties , Time Factors
16.
Orv Hetil ; 160(39): 1554-1562, 2019 Sep.
Article in Hungarian | MEDLINE | ID: mdl-31544495

ABSTRACT

Introduction and aim: Earlier results in the literature suggest that overweight subjects show weaker performance in executive function tasks as compared to normal weight people. Dopaminergic system is strongly linked to executive functions, body mass regulation and ingestion. The aim of the present study was to examine the possible relationship between DRD4 VNTR 7-repeat allele, body mass index and Stroop performance in a healthy adult population, and to draw psychogenetic conclusions. Method: 152 subjects without diabetic or psychiatric history participated in the study. Along with non-invasive DNA sampling, demographic, weight and height data were collected. The participants also solved the computerized Stroop task. 11 subjects belonged to the underweight (mean body mass index = 17.9 kg/m2), 98 subjects to the normal (mean body mass index = 21.8 kg/m2), and 43 subjects to the overweight (mean body mass index = 28.9 kg/m2) category. After grouping participants according to their body mass index and DRD4 VNTR genotype, we compared their mean performance to investigate the possible psychogenetic associations. Results: Body mass index and stimuli type showed significant interaction on error number (p = 0.045): subjects with normal body mass index made significantly less error as compared to under- and overweight subjects in incongruent trials. The 7-repeat allele carriers made tendentiously more errors than non-carriers. Normal weight people made less error - independently from their genotype -, while subjects with either low or high BMI carrying the 7-repeat allele made more errors compared to non-carriers. Conclusion: Under- and overweight subjects perform weaker where inhibition is necessary in the task. This may reflect their reactions to food-related situations. Orv Hetil. 2019; 160(39): 1554-1562.


Subject(s)
Alleles , Body Mass Index , Executive Function/physiology , Polymorphism, Genetic , Receptors, Dopamine D4/genetics , Adult , Genetics, Behavioral , Genotype , Humans , Minisatellite Repeats , Receptors, Dopamine D4/drug effects , Receptors, Dopamine D4/metabolism
17.
Article in English | MEDLINE | ID: mdl-30664971

ABSTRACT

INTRODUCTION: The activation of the ATP-gated P2RX7 (purinergic receptor P2X, ligand-gated ion channel, 7) produces microglial activation, a process which has been demonstrated in depression, bipolar disorder, and schizophrenia. Emerging data over the last years highlighted the importance of P2X7 cation channel as a potential drug target for these central nervous system disorders. The Gln460Arg (rs2230912) polymorphism of the P2RX7 gene has been widely studied in mood disorders, however the results are still controversial. Therefore, we aimed to investigate the C-terminal region of this gene in major depressive and bipolar disorders (MDD and BD) by studying possibly functional, non-synonymous polymorphisms within a 7 kb long region around the Gln460Arg, including Ala348Thr (rs1718119), Thr357Ser (rs2230911), and Glu496Ala (rs3751143) variants. Since Gln460Arg is located at the 3' end of the P2RX7 gene, we included additional, potentially functional single nucleotide polymorphisms (SNPs) from the 3' untranslated region (UTR), which can be in linkage with Gln460Arg. Based on in silico search, we chose two SNPs in putative microRNA target sites which are located in consecutive positions: rs1653625 and rs1718106. METHODS: P2RX7 SNPs from the C-terminal region were selected based on previous functional assays, 3' UTR variants were chosen using PolymiRTS and Patrocles databases. The genotyping of the non-synonymous SNPs was carried out by pre-designed TaqMan® kits, while the 3' UTR variants were analyzed by PCR-RFLP method. Case-control analyses were carried out between 315 inpatients with acute major depressive episode (195 MDD, 120 BD) and 406 healthy control subjects. The two subscales of the Hospital Anxiety and Depression Scale (HADS) self-report questionnaire were used for quantitative analyses, including an additional, "at-risk" population of 218 patients with diabetes mellitus. The in vitro reporter gene assays were carried out on HEK and SK-N-FI cells transiently transfected with pMIR vector constructs containing the P2RX7 3' UTR downstream of the luciferase gene. RESULTS: Haplotype analysis indicated a relatively high linkage between the analyzed P2RX7 SNPs. Our case-control study did not yield any association between P2RX7 gene variants and depression. However, dimensional analyses showed significant associations of the HADS depression severity scores with Gln460Arg (rs2230912) and Ala348Thr (rs1718119) in the depressed and diabetic patient groups. In the in vitro experiments, the P2RX7 3' UTR constructs with the lowest predicted binding efficiency to their miRNAs showed the highest expression of the gene. The combination of the depression-associated P2RX7 C-terminal and 3' UTR SNPs contributed to the highest depression severity score in the haplotype analysis. CONCLUSION: Based on our findings, we propose that a P2RX7 haplotype combination of the Gln460Arg and neighboring SNPs contribute to the observed genetic association with depressive symptoms.


Subject(s)
Bipolar Disorder/genetics , Depressive Disorder, Major/genetics , Genetic Predisposition to Disease , Polymorphism, Single Nucleotide , Receptors, Purinergic P2X7/genetics , Adult , Bipolar Disorder/metabolism , Case-Control Studies , Cell Line , Computer Simulation , Depressive Disorder, Major/metabolism , Diabetes Mellitus/genetics , Diabetes Mellitus/metabolism , Female , Gene Frequency , Genetic Association Studies , Haplotypes , Humans , Linkage Disequilibrium , Male , MicroRNAs/metabolism , Middle Aged , Psychiatric Status Rating Scales , Receptors, Purinergic P2X7/metabolism
18.
Prog Neuropsychopharmacol Biol Psychiatry ; 32(8): 1884-8, 2008 Dec 12.
Article in English | MEDLINE | ID: mdl-18801407

ABSTRACT

AIMS: Both diabetes mellitus and major depression are public health concerns, and the co-occurrence of these illnesses is highly frequent. Acting as a potential risk factor, hyperglycemia might facilitate the manifestation of depression in patients genetically predisposed to affective disorders. In the present study, candidate polymorphisms of the serotonin transporter, the tryptophan hydroxylase 2 (TPH2) genes, as well as of the brain-derived neurotrophic factor BDNF, and the P2RX7 purinergic receptor genes were analyzed in Hungarian diabetic population. We assumed that genetic influence would be stronger on depressive symptoms in the "poor glycemic control" group (PC: HbA1C>7%) compared to the "good glycemic control" group (GC: HbA1C

Subject(s)
Arginine/genetics , Depression/genetics , Diabetes Complications , Glutamine/genetics , Polymorphism, Genetic/genetics , Receptors, Purinergic P2/genetics , Brain-Derived Neurotrophic Factor/genetics , Depression/etiology , Diabetes Mellitus/physiopathology , Gene Frequency , Genetic Predisposition to Disease , Genotype , Humans , Multivariate Analysis , Receptors, Purinergic P2X7 , Serotonin Plasma Membrane Transport Proteins/genetics , Tryptophan Hydroxylase/genetics
19.
J Biochem Biophys Methods ; 70(5): 713-20, 2007 Aug 01.
Article in English | MEDLINE | ID: mdl-17509692

ABSTRACT

Distribution of serotonin (5-HT) content of nervous fibers in both the somatic and the visceral muscle of Eisenia fetida have been investigated using immunocytochemical staining and voltammetric measurements. The somatic muscles in the body wall are richer innervated with serotoninergic fibers than the visceral ones in the pharynx and gizzard. The relative density of immunopositive fibers in the circular muscle layer of the body wall was found to be 2.73% while in the prostomium it was 1.02%. In the case of the muscle in pharynx 1.12% and in gizzard 1.28% density values were found. Differential Pulse Voltammetric (DPV) measurements with carbon fiber electrodes in the above mentioned muscle layers gave 272.5 nA, 135.0 nA, 122.5 nA, 137.5 nA peak heights, respectively. In the statistical analysis T-test was used at a confidence level of 95% (p<0.05). DPV current peak (i(p)) values reflect clearly the 5-HT concentration differences. Significant correlation was found between the innervation density and the i(p) values recorded in different areas. The i(p) values recorded at different times in different locations are determined by instantaneous serotonin concentration of the living tissue. As far as we know this is the first report using in vivo voltammetry investigating serotonin content in earthworm, E. fetida.


Subject(s)
Muscles/metabolism , Oligochaeta/anatomy & histology , Oligochaeta/metabolism , Serotonin/metabolism , Animals , Electrochemistry , Gizzard, Non-avian/innervation , Gizzard, Non-avian/metabolism , Immunohistochemistry , In Vitro Techniques , Muscles/anatomy & histology , Muscles/innervation , Nerve Fibers/metabolism , Pharynx/innervation , Pharynx/metabolism , Tissue Distribution
20.
Physiol Meas ; 28(4): R41-55, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17395989

ABSTRACT

Chemical reactions, including oxidation and reduction of molecules, occur in every cell. These reactions can lead to the production of free radicals. Free radicals react with organic substrates such as lipids, proteins, and DNA. Through oxidation free radicals cause damage to these molecules, disturbing their normal function, and may therefore contribute to a variety of diseases. The anti-oxidation system, which consists of enzymatic antioxidants and non-enzymatic antioxidants, defends against oxidative stress. The aim of this review is to summarize general aspects of methods to measure the antioxidant defence system all in one (total antioxidant capacity) and discuss a number of methods which are currently used for detection of antioxidant properties.


Subject(s)
Antioxidants/analysis , Biological Assay/methods , Biosensing Techniques/methods , Microarray Analysis/methods , Oxidative Stress/physiology , Reactive Oxygen Species/analysis , Oxidation-Reduction
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