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1.
Pharmaceuticals (Basel) ; 17(6)2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38931382

RESUMO

The aim of this review is to present the potential application of camphor-a bicyclic monoterpene ketone-in the prevention of skin infections. Skin diseases represent a heterogeneous group of disorders characterized by prolonged symptoms that significantly diminish the quality of life. They affect the dermis, the epidermis, and even subcutaneous tissue. They very often have a bacterial or fungal background. Therapy for dermatological skin disorders is difficult and long-term. Therefore, it is important to find a compound, preferably of natural origin, that (i) prevents the initiation of this infection and (ii) supports the skin's repair process. Based on its documented anti-inflammatory, antibacterial, antifungal, anti-acne, anesthetic, strengthening, and warming properties, camphor can be used as a preventative measure in dermatological infectious diseases and as a component in medical and cosmetic products. This work discusses the structure and physicochemical properties of camphor, its occurrence, and methods of obtaining it from natural sources as well as through chemical synthesis. The use of camphor in industrial preparations is also presented. Additionally, after a detailed review of the literature, the metabolism of camphor, its interactions with other medicinal substances, and its antimicrobial properties against bacteria and fungi involved in skin diseases are discussed with regard to their resistance.

2.
Molecules ; 29(12)2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38930886

RESUMO

The aim of this study was to obtain new halolactones with a gem-dimethyl group in the cyclohexane ring (at the C-3 or C-5 carbon) and a methyl group in the lactone ring and then subject them to biotransformations using filamentous fungi. Halolactones in the form of mixtures of two diasteroisomers were subjected to screening biotransformations, which showed that only compounds with a gem-dimethyl group located at the C-5 carbon were transformed. Strains from the genus Fusarium carried out hydrolytic dehalogenation, while strains from the genus Absidia carried out hydroxylation of the C-7 carbon. Both substrates and biotransformation products were then tested for antimicrobial activity against multidrug-resistant strains of both bacteria and yeast-like fungi. The highest antifungal activity against C. dubliniensis and C. albicans strains was obtained for compound 5b, while antimicrobial activity against S. aureus MRSA was obtained for compound 4a.


Assuntos
Antibacterianos , Biotransformação , Lactonas , Testes de Sensibilidade Microbiana , Lactonas/química , Lactonas/farmacologia , Lactonas/metabolismo , Antibacterianos/farmacologia , Antibacterianos/química , Fusarium/efeitos dos fármacos , Antifúngicos/farmacologia , Antifúngicos/química , Absidia/metabolismo , Estrutura Molecular , Candida albicans/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos
3.
Molecules ; 29(7)2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38611862

RESUMO

The current research is an attempt to analyze on-site selenium(IV) ions in environmental water samples using an eco-friendly miniaturized sensor developed by deposition of a very thin amount of metallic bismuth in a solid Bi electrode tightly closed in miniaturized housing. Numerous experimental variables are optimized, including the composition of the supporting electrolyte and its pH, as well as activation and accumulation conditions. Under optimized measurement conditions, the method shows high sensitivity, permitting a very low limit of detection equal to 7 × 10-10 mol L-1 to be achieved in a short accumulation time of 50 s. The performance of this microsensor was investigated against numerous interference factors and its good anti-interference capability was demonstrated. A series of voltammetric experiments by differential pulse cathodic stripping voltammetry (DPCSV) were carried out and they proved that the miniaturized sensor is characterized by very good accuracy and precision as well as long-term stability. The solid bismuth microelectrode displays a good voltammetric response in the analysis of diverse samples with a complex matrix and demonstrates a good recovery rate.

4.
Molecules ; 29(6)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38542835

RESUMO

A simple and fast stripping voltammetric procedure for trace determination of Ce(III) in environmental water samples has been developed. The procedure of cerium determination in the presence of Alizarin S and acetate buffer was employed as the initial method. The adsorption material, multi-walled carbon nanotubes, was used as a screen-printed electrode modifier ensuring efficient accumulation of the Ce(III)-Alizarin S complex. The calibration graph for Ce(III) for an accumulation time of 60 s was linear in the range from 1 × 10-8 to 7 × 10-7 mol L-1 with the linear correlation coefficient r = 0.997. The detection limit was estimated from three times the standard deviation of low Ce(III) concentration and an accumulation time of 60 s was about 3.5 × 10-9 mol L-1. The proposed method was successfully applied to Ce(III) determination at trace levels in environmental water samples, such as river, lake and rain water with recoveries ranged from 93% to 98%.

5.
Medicina (Kaunas) ; 60(3)2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38541119

RESUMO

This review summarizes the complex relationship between medications used to treat type 2 diabetes and bone health. T2DM patients face an increased fracture risk despite higher bone mineral density; thus, we analyzed the impact of key drug classes, including Metformin, Sulphonylureas, SGLT-2 inhibitors, DPP-4 inhibitors, GLP-1 agonists, and Thiazolidinediones. Metformin, despite promising preclinical results, lacks a clear consensus on its role in reducing fracture risk. Sulphonylureas present conflicting data, with potential neutral effects on bone. SGLT-2 inhibitors seem to have a transient impact on serum calcium and phosphorus, but evidence on their fracture association is inconclusive. DPP-4 inhibitors emerge as promising contributors to bone health, and GLP-1 agonists exhibit positive effects on bone metabolism, reducing fracture risk. Thiazolidinediones, however, demonstrate adverse impacts on bone, inducing loss through mesenchymal stem cell effects. Insulin presents a complex relationship with bone health. While it has an anabolic effect on bone mineral density, its role in fracture risk remains inconsistent. In conclusion, a comprehensive understanding of diabetes medications' impact on bone health is crucial. Further research is needed to formulate clear guidelines for managing bone health in diabetic patients, considering individual profiles, glycemic control, and potential medication-related effects on bone.


Assuntos
Diabetes Mellitus Tipo 2 , Inibidores da Dipeptidil Peptidase IV , Fraturas Ósseas , Metformina , Inibidores do Transportador 2 de Sódio-Glicose , Tiazolidinedionas , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Densidade Óssea , Hipoglicemiantes/uso terapêutico , Inibidores da Dipeptidil Peptidase IV/farmacologia , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Fraturas Ósseas/etiologia , Fraturas Ósseas/prevenção & controle , Metformina/uso terapêutico , Compostos de Sulfonilureia/efeitos adversos , Peptídeo 1 Semelhante ao Glucagon/farmacologia , Peptídeo 1 Semelhante ao Glucagon/uso terapêutico , Tiazolidinedionas/uso terapêutico
6.
Materials (Basel) ; 17(4)2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38399216

RESUMO

This work presents a proposal for an adsorptive stripping voltammetric (AdSV) method for gallium(III) determination at an eco-friendly multiwall carbon nanotube/spherical glassy carbon (MWCNT/SGC) electrode modified with a lead film. The operational factors influencing the sensitivity of the AdSV procedure were thoroughly investigated, and their most favorable values were chosen (0.1 mol L-1 acetate buffer solution pH = 5.6; 7 × 10-5 mol L-1 Pb(II); 2 × 10-4 mol L-1 cupferron; potential/time of lead film formation: -1.9 V/30 s; potential/time of Ga(III)-cupferron adsorption: -0.75 V/30 s). The newly developed MWCNT/SGCE has proven to be a competitive substrate to the glassy carbon electrode to create a lead film electrode, since it allows the determination of gallium in a wider range of concentrations from 3 × 10-9 to 4 × 10-7 mol L-1 with a lower limit of detection equal to 9.5 × 10-10 mol L-1. The elaborated procedure has been shown to be highly selective and insensitive to the presence of an even 100-fold excess of most of the ions commonly found in environmental waters. The MWCNT/SGC sensor, which can maintain >95% of its original response after 70 days of use, has been successfully applied for the detection of gallium in water samples with the relative standard deviation (RSD) ranging from 4.5% to 6.2% (n = 3) and recoveries in the range from 95.3% to 104.9%.

7.
Membranes (Basel) ; 14(2)2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38392680

RESUMO

A copper film-modified, carboxyl-functionalized, and multi-walled carbon nanotube (MWCNT-COOH)-modified screen-printed carbon electrode (CuF/MWCNTs/SPCE) was used for lead determination using anodic stripping voltammetry. The main parameters were investigated and optimized during the development of the research procedure. The most optimal electrolyte concentrations were determined to be 0.4 M HCl and 6.3 × 10-5 M Cu(II). The optimal parameters for voltammetric stripping measurements are as follows: an accumulation potential of -0.7 V; an accumulation time of 120 s; and a pulse amplitude and pulse time of 120 mV and 2 ms, respectively. The effect of surface active substances and humic substances as potential interferents present in aqueous environmental samples was investigated. The validation of the procedure was carried out using certified reference materials, like waste water SPS-WW1 and environmental matrix TM-25.5. In addition, the developed procedure was applied to investigate lead recovery from natural environmental water, such as rivers and lakes.

9.
Chemphyschem ; 25(2): e202300633, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37921492

RESUMO

A method for the voltammetric determination of tin using a multiwall carbon nanotubes/spherical glassy carbon (CNTs/SGC) electrode is described. The new procedure is based on the adsorptive accumulation of the Sn(II)-cupferron complex on a CNTs/SGC electrode modified with a lead film, followed by electrochemical reduction of the adsorbed species. The optimal experimental conditions include the use of 0.10 mol L-1 acetate buffer (pH 5.7), 4.0×10-4 M cupferron and 1.0×10-4 M Pb(II). The peak current is proportional to the concentration of Sn(II) over the range of 1.0×10-9 -1.0×10-7 M and the detection limit is 3.1×10-10 M for a 95 s accumulation time. The proposed method was used to determine tin in real samples and certified reference materials.

10.
Molecules ; 28(23)2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38067485

RESUMO

This paper presents an overview of approaches proposed in the scientific literature for the voltammetric determination of rare earth elements (mainly cerium and europium individually, as well as various lanthanides simultaneously) in manifold kinds of samples. The work is divided into chapters describing the most important aspects affecting the sensitivity of the proposed methods: the technique adopted (AdSV, ASV, CSV), complexing agents used, the kind of working electrode (mercury-based, noble metal or carbon electrodes) and the most popular electrode modifiers (e.g., metal film, carbon nanotubes, molecularly imprinted polymers). Analytical parameters of the procedures presented in the paper are collected in tables. The subsequent chapters are devoted to a detailed discussion of potential inorganic and organic interfering factors. The possibilities of simultaneous determination of several lanthanides in one sample and the influence of other lanthanides on the determined rare earth element were also discussed. Finally, the applications of the voltammetric procedures to the determination of rare earth metals in real samples with miscellaneous matrix is described. All analytical results were tabulated in order to compare the analytical suitability of the proposed procedures.

11.
Materials (Basel) ; 16(24)2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38138688

RESUMO

Tin determination allows for the monitoring of pollution and assessment of the impact of human activities on the environment. The determination of tin in the environment is crucial for the protection of human health and ecosystems, and for maintaining sustainability. Tin can be released into the environment from various sources, such as industry, transportation, and electronic waste. The concentration of tin in the environment can be determined by different analytical methods, depending on the form of tin present and the purpose of the analysis. The choice of an appropriate method depends on the type of sample, concentration levels, and the available instrumentation. In this paper, we have carried out a literature review of electrochemical methods for the determination of tin. Electrochemical methods of analysis such as polarography, voltammetry, and potentiometry can be used for the determination of tin in various environmental samples, as well as in metal alloys. The detection limits and linearity ranges obtained for the determination of tin by different electrochemical techniques are collected and presented. The influence of the choice of base electrolyte and working electrode on signals is also presented. Practical applications of the developed tin determination methods in analyzing real samples are also summarized.

12.
J Cardiovasc Dev Dis ; 10(8)2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37623342

RESUMO

Hypercholesterolemia is the main cardiovascular (CV) risk factor with a large body of evidence. Our aim was to assess the achievement of the main therapeutic goal of Low-Density Lipoprotein Cholesterol (LDL-C) in patients with a very high CV risk and a high-dose statin therapy. The study group consisted of 1413 consecutive patients hospitalised at the Upper-Silesian Medical Centre in Katowice due to acute myocardial infarction (AMI) treated with atorvastatin ≥ 40 mg or rosuvastatin ≥ 20 mg. The lipid profile was performed on admission and within 12 months after AMI. The main therapeutic goal was defined as LDL-C < 55 mg%. The study group (n = 1413) included 979 males (69.3%) with arterial hypertension (83.3%), diabetes (33.5%), peripheral artery disease (13.6%) and nicotinism (46.2%). In the study group, only 61 patients (4.3%) were additionally taking ezetimibe. During hospitalisation, the primary LDL-C goal was found in only 186 patients (13.2%). Subsequently, a follow-up lipidogram within 12 months was performed in 652 patients (46%), and the therapeutic goal was achieved in 255 patients (39%). There were 258 (18.26%) patients who died within 12 months after myocardial infarction. The lowest mortality rate was found in the subgroup of patients with LDL-C < 55 mg% during follow-up (11.02%). The primary lipid goal attainment among patients with a high-dose statin and a very high CV risk is low and far from the expected rate. Patients hospitalised for AMI should be given a combination of statin and ezetimibe more frequently. Low LDL-C levels measured at follow-up predict a lower risk of death at 12-month follow-up in a large group of patients.

13.
Sensors (Basel) ; 23(12)2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37420564

RESUMO

Sumatriptan is an organic chemical compound from the tryptamine group. It is used as a medicine for migraine attacks and in the treatment of cluster headaches. In this work, a new voltammetric method is proposed for highly sensitive SUM determination, using glassy carbon electrodes modified with carbon black and titanium dioxide suspension. The novelty of the presented work is the usage of the mixture of carbon black and TiO2 as glassy carbon electrode modifier for the first time for SUM determination. The mentioned sensor was characterized by great repeatability and sensitivity of measurements, which resulted in the obtention of a wide range of linearity and a low detection limit. The electrochemical properties of the CB-TiO2/GC sensor was characterized using the LSV and EIS method. The effect of different factors on the SUM peak, such as supporting electrolyte type, preconcentration time and potential, or influence of interferents, were tested using the square wave voltammetry technique. The linear voltammetric response for the analyte was obtained in the concentration range of 5 nmol L-1 to 150 µmol L-1 with a detection limit of 2.9 nmol L-1 for a preconcentration time of 150 s in the 0.1 mol L-1 phosphate buffer pH 6.0. The proposed method was successfully applied for highly sensitive sumatriptan determination in complex matrices, such as tablets, urine, and plasma, with a good recovery parameter (94-105%). The presented CB-TiO2/GC electrode is characterized by great stability, it was used for 6 weeks without significant changes in the SUM peak current. Amperometric and voltammetric measurements of SUM under the flow injection conditions were also performed to indicate the possibility of its fast and accurate determination with a time of single analysis of approx. 30 s.


Assuntos
Carbono , Sumatriptana , Carbono/química , Análise de Injeção de Fluxo , Fuligem , Eletrodos , Fosfatos , Técnicas Eletroquímicas
14.
Sensors (Basel) ; 23(13)2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37447689

RESUMO

Potentiometric sensors are the largest and most commonly used group of electrochemical sensors. Among them, ion-selective electrodes hold a prominent place. Since the end of the last century, their re-development has been observed, which is a consequence of the introduction of solid contact constructions, i.e., electrodes without an internal electrolyte solution. Research carried out in the field of potentiometric sensors primarily focuses on developing new variants of solid contact in order to obtain devices with better analytical parameters, and at the same time cheaper and easier to use, which has been made possible thanks to the achievements of material engineering. This paper presents an overview of new materials used as a solid contact in ion-selective electrodes over the past several years. These are primarily composite and hybrid materials that are a combination of carbon nanomaterials and polymers, as well as those obtained from carbon and polymer nanomaterials in combination with others, such as metal nanoparticles, metal oxides, ionic liquids and many others. Composite materials often have better mechanical, thermal, electrical, optical and chemical properties than the original components. With regard to their use in the construction of ion-selective electrodes, it is particularly important to increase the capacitance and surface area of the material, which makes them more effective in the process of charge transfer between the polymer membrane and the substrate material. This allows to obtain sensors with better analytical and operational parameters. Brief characteristics of electrodes with solid contact, their advantages and disadvantages, as well as research methods used to assess their parameters and analytical usefulness were presented. The work was divided into chapters according to the type of composite material, while the data in the table were arranged according to the type of ion. Selected basic analytical parameters of the obtained electrodes have been collected and summarized in order to better illustrate and compare the achievements that have been described till now in this field of analytical chemistry, which is potentiometry. This comprehensive review is a compendium of knowledge in the research area of functional composite materials and state-of-the-art SC-ISE construction technologies.


Assuntos
Eletrodos Seletivos de Íons , Polímeros , Eletrodos , Polímeros/química , Óxidos , Potenciometria , Carbono/química
15.
Medicina (Kaunas) ; 59(5)2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37241119

RESUMO

Background and Objectives: It is well established that patients with cognitive impairment are at a higher risk of falls. However, the impact of coexisting neuropsychiatric symptoms on the overall risk of falls in hospitalized geriatric individuals with and without dementia has not been extensively studied. This cross-sectional study will assess the association between neuropsychiatric symptoms and fall risk in geriatric individuals analyzed by sex. Materials and Methods: A total of 234 patients, both with and without dementia, admitted to the geriatric ward at Leszek Giec Upper-Silesian Medical Centre of the Silesian Medical University in Katowice, Poland, between January 2019 and January 2020 were included in this study. The Neuropsychiatric Inventory-Questionnaire was used to assess the presence of neuropsychiatric symptoms. Increased fall risk was defined by Berg scores of ≤40. Results: The mean age of the study group was 80.7 ± 6.6, and women accounted for 62.8% of the study population. Apathy was the most common neuropsychiatric symptom, affecting 58.1% of patients, and it was the most common symptom among people with dementia, affecting 67.80% of patients. The receiver operating characteristics curve analysis revealed that a high fall risk was significantly associated with the total number of neuropsychiatric symptoms (≥4) and the total intensity of these symptoms (≥6). For women, high fall risk was associated with three or more neuropsychiatric symptoms and a total neuropsychiatric symptom intensity score of at least 6. For men, the association of high fall risk with the total number of NPS was not significant; a total NPS intensity score of 10 or more was associated with high fall risk. Multivariate logistic regression analysis identified associations with fall risk for hallucinations. Conclusions: Our results suggest that the presence of neuropsychiatric symptoms, particularly hallucinations is associated with an increased risk of falls in geriatric inpatients. In addition, the cumulative total of NPS and their cumulative intensity are both independently associated with an increased risk of falls. These results suggest that fall prevention strategies should include the management of neuropsychiatric symptoms in hospitalized geriatric individuals.


Assuntos
Disfunção Cognitiva , Demência , Masculino , Humanos , Feminino , Idoso , Pacientes Internados , Estudos Transversais , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/psicologia , Acidentes por Quedas/prevenção & controle , Demência/epidemiologia , Demência/etiologia , Demência/psicologia , Alucinações , Fatores de Risco
16.
Materials (Basel) ; 16(10)2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37241271

RESUMO

The main purpose of this review is to present methods of adsorptive stripping voltammetry that can be used to determine trace amounts of VO2(+) in various types of samples. The detection limits achieved using different working electrodes are presented. The factors influencing the obtained signal, including the selection of the complexing agent and the selection of the working electrode, are shown. For some methods, in order to increase the range of applied concentrations in which vanadium can be detected, a catalytic effect is introduced to adsorptive stripping voltammetry. The influence of the foreign ions and organic matter contained in natural samples on the vanadium signal is analyzed. This paper presents methods of elimination associated with the presence of surfactants in the samples. The methods of adsorptive stripping voltammetry for the simultaneous determination of vanadium with other metal ions are also characterized below. Finally, the practical use of the developed procedures, mainly for the analysis of food and environmental samples, is summarized in a tabular version.

17.
Antibiotics (Basel) ; 12(5)2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37237727

RESUMO

The main purpose of this article is to present the latest research related to selected biological properties of carvacrol, such as antimicrobial, anti-inflammatory, and antioxidant activity. As a monoterpenoid phenol, carvacrol is a component of many essential oils and is usually found in plants together with its isomer, thymol. Carvacrol, either alone or in combination with other compounds, has a strong antimicrobial effect on many different strains of bacteria and fungi that are dangerous to humans or can cause significant losses in the economy. Carvacrol also exerts strong anti-inflammatory properties by preventing the peroxidation of polyunsaturated fatty acids by inducing SOD, GPx, GR, and CAT, as well as reducing the level of pro-inflammatory cytokines in the body. It also affects the body's immune response generated by LPS. Carvacrol is considered a safe compound despite the limited amount of data on its metabolism in humans. This review also discusses the biotransformations of carvacrol, because the knowledge of the possible degradation pathways of this compound may help to minimize the risk of environmental contamination with phenolic compounds.

18.
Materials (Basel) ; 16(8)2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37110088

RESUMO

The practical application of a novel, eco-friendly electrochemical sensor based on low-dimensional structures, spherical glassy carbon microparticles, and multiwall carbon nanotubes is described. This sensor, modified with a bismuth film, was used for the determination of Cd(II) by the anodic stripping voltammetric method. The instrumental and chemical factors influencing the sensitivity of the procedure were thoroughly investigated and their most favorable values were selected (acetate buffer solution pH = 3 ± 0.1; 0.15 mmol L-1 Bi(III); activation potential/time: -2 V/3 s; accumulation potential/time: -0.9 V/50 s). Under the selected conditions, the method exhibited linearity in the range of 2 × 10-9 to 2 × 10-7 mol L-1 Cd(II) with a detection limit of 6.2 × 10-10 mol L-1 Cd(II). The results obtained also showed that the application of the sensor for Cd(II) detection did not experience any significant interference in the presence of a number of foreign ions. The applicability of this procedure was evaluated using TM-25.5 Environmental Matrix Reference Material and SPS-WW1 Waste Water Certified Reference Material as well as river water samples through addition and recovery tests.

19.
Materials (Basel) ; 16(3)2023 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-36770010

RESUMO

A new solid-contact ion-selective electrode (ISE) sensitive to lead (II) ions, obtained by modifying a polymer membrane with a nanocomposite of carbon nanofibers and an ionic liquid 1-hexyl-3-methylimidazolium hexafluorophosphate, is presented. Electrodes with a different amount of nanocomposite in the membrane (0-9% w/w), in which a platinum wire or a glassy carbon electrode was used as an internal electrode, were tested. Potentiometric and electrochemical impedance spectroscopy measurements were carried out to determine the effect of the ion-sensitive membrane modification on the analytical and electrical parameters of the ion-selective electrode. It was found that the addition of the nanocomposite causes beneficial changes in the properties of the membrane, i.e., a decrease in resistance and an increase in capacitance and hydrophobicity. As a result, the electrodes with the modified membrane were characterized by a lower limit of detection, a wider measuring range and better selectivity compared to the unmodified electrode. Moreover, a significant improvement in the stability and reversibility of the electrode potential was observed, and additionally, they were resistant to changes in the redox potential of the sample. The best parameters were shown by the electrode obtained with the use of a platinum wire as the inner electrode with a membrane containing 6% of the nanocomposite. The electrode exhibited a Nernstian response to lead ions over a wide concentration range, 1.0 × 10-8-1.0 × 10-2 mol L-1, with a slope of 31.5 mV/decade and detection limit of 6.0 × 10-9 mol L-1. In addition, the proposed sensor showed very good long term stability and worked properly 4 months after its preparation without essential changes in the E0 or slope values. It was used to analyze a real sample and correct results of lead content determination were obtained.

20.
Pediatr Endocrinol Diabetes Metab ; 29(4): 259-266, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38282495

RESUMO

DiGeorge syndrome is associated with microdeletion of chromosome 22q11. Hypoplasia of the thymus, hypoparathyroidism, facial malformations and cardiac defects as well as learning difficulties are typical features of the disease. On the other hand hypocalcemia related to hypoparathyroidism is not present in every patient and can develop later and be persistent or transient and is often masked by the other signs or symptoms. We described a 13-year-old boy diagnosed with DiGeorge syndrome, after a few years of nonspecific signs and symptoms, and a microarray examination performed because myopathy was suspected on the basis of elevated creatine kinase activity. Only after molecular confirmation of DiGeorge syndrome the patient was referred to a pediatric endocrinologist and proper therapy started. Looking back to his medical history, low calcium levels were at least 2 times reported in the medical records, the child had learning difficulties, speech disturbances, and submucosal cleft palate suspicion. In conclusion it is important to educate general practitioners and pediatricians to check the serum calcium levels in patients presenting with nonspecific, muscular signs and symptoms.


Assuntos
Síndrome de DiGeorge , Hipoparatireoidismo , Adolescente , Humanos , Masculino , Cálcio , Deleção Cromossômica , Diagnóstico Tardio , Síndrome de DiGeorge/complicações , Síndrome de DiGeorge/diagnóstico , Síndrome de DiGeorge/genética , Hipoparatireoidismo/genética
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