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1.
J Trace Elem Med Biol ; 60: 126478, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32146340

RESUMO

Alkali metals (AMs) and alkali earth metals (AEMs) affect levels and signaling of neurotransmitters, which potentially play a role in the etiology of schizophrenia (SCZ). The current case-control study aims to explore how AMs [i.e. Potassium (K), sodium (Na), rubidium (Rb), cesium (Cs)] and AEMs [i.e. magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba)] in serum could associate with SCZ. One hundred and five inpatients with SCZ and 106 age- and sex-matched healthy controls (HCs) were recruited from Weifang, China. Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) was used to evaluate serum concentrations of Na, K, Ca, Mg and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) was for Rb, Cs, Sr, Ba. Subjects with SCZ had significantly higher Mg and Sr serum concentrations than HCs (20.86 vs. 19.73 µg/mL of Mg, p < 0.001; 53.14 vs. 42.26 ng/mL of Sr, p < 0.001). After adjusting for confounders, the odds ratio of Mg and Sr remain significantly higher in the SCZ group (Mg: OR = 2.538, 95 % CI: 1.254-5.136, p=0.010; Sr: OR = 3.798, 95 % CI: 1.769-8.153, p = 0.001). No significant differences between SCZ subjects and HCs were observed for other AMs and AEMs. Higher serum concentrations of Mg and Sr were associated with SCZ. Studies are suggested to find the related mechanisms and provide clues for pathogenesis of SCZ, which would impact prevention and treatments of SCZ.


Assuntos
Metais Alcalinos/efeitos adversos , Metais Alcalinoterrosos/efeitos adversos , Esquizofrenia/induzido quimicamente , Adolescente , Adulto , Estudos de Casos e Controles , China , Feminino , Humanos , Masculino , Metais Alcalinos/sangue , Metais Alcalinoterrosos/sangue , Fatores de Risco , Esquizofrenia/patologia , Adulto Jovem
2.
Biol Trace Elem Res ; 194(1): 13-23, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31073699

RESUMO

Human blood is a complex sample matrix when elemental analysis is considered. In this study, the effects of Na, a natural component of serum samples, was investigated in the quantitative determination of Ca, K, Mg, Cu, Zn, and Fe by microwave plasma atomic emission spectrometry. The robustness of the microwave plasma was tested by evaluating MgII 280.271 nm/MgI 285.213 nm by varying two adjustable operating parameters, the read time, and the nebulizer pressure. The read time has no influence on the robustness while the MgII/MgI ratio decreased when the nebulizer pressure was increased during the analysis. The threshold concentrations of the interfering Na were determined at the analytical lines used for the measurement of other elements. The matrix effect of the commercially available microwave plasma was studied by a series of model experiments with human blood. The increasing concentration of Na in the matrix within the normal ranges reported for blood serum increased the intensities of the measured atomic lines. According to a factorial design-where two applied factors were the concentration of Na matrix and the measured elements as well as their levels were considered as factorial points-it was found that the Na concentration in a serum sample after acid digestion and 10 times dilution affected the intensity values of the measured elements. For Ca, Cu, and Fe, a statistically significant effect was observed, while for Zn, Mg, and K, an interaction effect was also found. However, after calculating the percentage errors caused by the shift, the relative difference was observed to be quite small (< 10%).


Assuntos
Metais Alcalinos/sangue , Metais Alcalinoterrosos/sangue , Metais Pesados/sangue , Micro-Ondas , Humanos , Modelos Moleculares , Soluções
4.
An Acad Bras Cienc ; 89(1 Suppl 0): 445-456, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28492734

RESUMO

This study investigated the anesthetic potential of the essential oil (EO) of Aloysia polystachya in juveniles of dusky grouper (Epinephelus marginatus). Fish were exposed to different concentrations of EO of A. polystachya to evaluate time of induction and recovery from anesthesia. In the second experiment, fish were divided into four groups: control, ethanol and 50 or 300 µL L-1 EO of A. polystachya, and each group was submitted to induction for 3.5 min and recovery for 5 or 10 min. The blood gases and glucose levels showed alterations as a function of the recovery times, but Na+ and K+ levels did not show any alteration. In conclusion, the EO from leaves of A. polystachya is an effective anesthetic for dusky grouper, because anesthesia was reached within the recommended time at EO concentrations of 300 and 400 µL L-1. However, most evaluated blood parameters showed compensatory responses due to EO exposure.


Assuntos
Anestésicos/farmacologia , Biomarcadores/sangue , Peixes-Gato/sangue , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Verbenaceae/química , Animais , Bicarbonatos/sangue , Gases/sangue , Glucose/análise , Hematócrito , Hemoglobinas/análise , Concentração de Íons de Hidrogênio , Metais Alcalinos/sangue , Folhas de Planta/química
5.
An. acad. bras. ciênc ; 89(1,supl): 445-456, May. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-886648

RESUMO

ABSTRACT This study investigated the anesthetic potential of the essential oil (EO) of Aloysia polystachya in juveniles of dusky grouper (Epinephelus marginatus). Fish were exposed to different concentrations of EO of A. polystachya to evaluate time of induction and recovery from anesthesia. In the second experiment, fish were divided into four groups: control, ethanol and 50 or 300 µL L−1 EO of A. polystachya, and each group was submitted to induction for 3.5 min and recovery for 5 or 10 min. The blood gases and glucose levels showed alterations as a function of the recovery times, but Na+ and K+ levels did not show any alteration. In conclusion, the EO from leaves of A. polystachya is an effective anesthetic for dusky grouper, because anesthesia was reached within the recommended time at EO concentrations of 300 and 400 µL L−1. However, most evaluated blood parameters showed compensatory responses due to EO exposure.


Assuntos
Animais , Peixes-Gato/sangue , Óleos de Plantas/farmacologia , Óleos Voláteis/farmacologia , Biomarcadores/sangue , Verbenaceae/química , Anestésicos/farmacologia , Bicarbonatos/sangue , Hemoglobinas/análise , Folhas de Planta/química , Gases/sangue , Glucose/análise , Hematócrito , Concentração de Íons de Hidrogênio , Metais Alcalinos/sangue
6.
J Trace Elem Med Biol ; 27(4): 273-85, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23643248

RESUMO

A comprehensive review of the analytical literature revealed substantial under-representation of trace element concentrations in fish blood, particularly for marine species. We describe a simple dilution procedure to measure Li, Mg, K, Ca, Mn, Cu, Zn, Se, Rb, Sr, Ba and Pb concentrations in low volumes of blood plasma of adult plaice (Pleuronectes platessa) using high resolution-inductively coupled plasma-mass spectrometry (HR-ICP-MS). Captive male and female plaice (n = 18) were serially sampled for one year and samples collected outside of the spawning season (n = 157) used to estimate reference ranges for this species. Method accuracy was deemed satisfactory, based on its application to the analysis of a certified reference material. Precision was generally <3%, with the most conservative measure of precision being ≤10% for all elements except Pb (∼20%). This is the first study to analyse fish blood plasma by ICP-MS and includes some of the first reference ranges for trace element concentrations in fish blood.


Assuntos
Linguado/sangue , Metais Alcalinos/sangue , Metais Alcalinoterrosos/sangue , Oligoelementos/sangue , Animais , Feminino , Masculino , Espectrometria de Massas
7.
Dement Geriatr Cogn Disord ; 25(6): 508-15, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18463412

RESUMO

BACKGROUND/AIMS: The homeostasis of essential metals such as copper, iron, selenium and zinc may be altered in the brain of subjects with Alzheimer's disease (AD). METHODS: Concentrations of metals (magnesium, calcium, vanadium, manganese, iron, cobalt, nickel, copper, zinc, selenium, rubidium, strontium, molybdenum, cadmium, tin, antimony, cesium, mercury and lead) were determined in plasma and cerebrospinal fluid (CSF) by inductively coupled plasma mass spectrometry in 173 patients with AD and in 87 patients with the combination of AD and minor vascular components (AD + vasc). Comparison was made with 54 healthy controls. RESULTS: The plasma concentrations of manganese and total mercury were significantly higher in subjects with AD (p < 0.001) and AD + vasc (p

Assuntos
Doença de Alzheimer/sangue , Doença de Alzheimer/líquido cefalorraquidiano , Metais/sangue , Metais/líquido cefalorraquidiano , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Metais Alcalinos/sangue , Metais Alcalinos/líquido cefalorraquidiano , Metais Alcalinoterrosos/sangue , Metais Alcalinoterrosos/líquido cefalorraquidiano , Metais Pesados/sangue , Metais Pesados/líquido cefalorraquidiano , Pessoa de Meia-Idade
8.
J Pharm Biomed Anal ; 43(2): 659-65, 2007 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-17079109

RESUMO

A chemometric approach based on experimental design and desirability functions was used to develop and validated a method for the determination of some metals of biological concern by a fast sequential ICP-AES. The elements considered are Al, Fe, Mn, Zn, Li, Na and K. The experimental design was used to investigate the effects of three instrumental most crucial parameters, such as sheath gas flow rate, pump speed and auxiliary gas flow rate. In order to improve the multielemental analysis speed, although a sequential instrument allows the use of a separate parameter set for each wavelength, regression models and desirability functions were applied to find the experimental conditions providing the highest global sensitivity. Validation was performed in terms of limits of detection (LOD), limits of quantitation (LOQ), linearity, precision and recovery. By using the 167.02 nm wavelength, aluminium LOD was 0.5 microg L(-1) while the highest LOD was found for K (65 microg L(-1)). A linear range of at least three orders of magnitude was statistically demonstrated for each element. Precision was evaluated by testing two concentration levels, and good results in terms of intra-day repeatability were obtained, with R.S.D. values lower than 4.1% at the lowest concentration level. Lacking a suitable certified reference material, trueness was estimated using the recovery rate on fortified samples. The validated method was then used in the quantification of the elements considered in a serum sample.


Assuntos
Alumínio/sangue , Metais Alcalinos/sangue , Metais Pesados/sangue , Espectrofotometria Atômica/métodos , Humanos , Ferro/sangue , Modelos Lineares , Lítio/sangue , Manganês/sangue , Doenças do Sistema Nervoso/sangue , Potássio/sangue , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Sódio/sangue , Zinco/sangue
9.
Nephron ; 83(3): 226-36, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10529629

RESUMO

BACKGROUND: In the past, nephrologists have been troubled by electrolyte disturbances and consequently focused their attention on the importance of maintaining the concentrations of electrolytes within the normal range. However, information about the potential role of trace elements in chronic renal failure is scarce. METHODS: During hemodialysis sessions, the concentrations of the five alkali metal cations lithium (Li), sodium (Na), potassium (K), rubidium (Rb), and cesium (Cs) have been determined in plasma and dialysis fluids of chronic hemodialysis patients by inductively coupled plasma mass spectrometry (Li, Rb, Cs) and by ion-sensitive electrodes (Na, K). Strict quality control schemes were applied to all analytical procedures to ensure accuracy and precision of the results. RESULTS: The plasma concentrations of the elements Li, Cs, Rb, and K distinctly decreased to 29, 50, 69, and 71%, respectively, of their initial values during hemodialysis. Simultaneously, the concentrations of these elements in dialysis fluids at the outlet of the dialyzer increased approximately 13-fold for Rb, 11-fold for Li, 3-fold for Cs, and 2-fold for K as compared with the inlet values. The concentrations of Na in plasma and dialysis fluids were almost identical and did not change during hemodialysis. CONCLUSIONS: Li, Rb, and Cs were depleted in hemodialysis patients, although the plasma concentrations of these trace elements still remained within the reference ranges for healthy adults. Consequently, further studies are needed to elucidate the clinical importance and long-term effects of these trace element imbalances - for example, CNS disturbances associated with diminished concentrations of Rb - in hemodialysis patients.


Assuntos
Falência Renal Crônica/sangue , Falência Renal Crônica/terapia , Metais Alcalinos/sangue , Potássio/sangue , Diálise Renal , Sódio/sangue , Adulto , Idoso , Césio/análise , Césio/sangue , Química Clínica/normas , Soluções para Diálise/administração & dosagem , Soluções para Diálise/química , Feminino , Humanos , Lítio/análise , Lítio/sangue , Masculino , Metais Alcalinos/análise , Pessoa de Meia-Idade , Potássio/análise , Controle de Qualidade , Rubídio/análise , Rubídio/sangue , Sódio/análise
11.
Acta Physiol Scand ; 108(1): 31-7, 1980 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7376905

RESUMO

This work deals with the possibility that cations may be transported through the human red blood cell membrane as negatively charged ion pairs of the type XCO3-. Passive sodium influx into human erythrocytes was increased 4-fold when 150 mM chloride was substituted with bicarbonate in the medium. This increased permeability to sodium was completely abolished when the cells were pretreated with a specific inhibitor of anion transport (DIDS). Both bicarbonate-induced sodium influx and chloride exchange were linearly related to DIDS-binding. Both transport processes were completely inhibited by the binding of 1.1 X 10(6) DIDS molecules per cell. The presence of bicarbonate and/or pretreatment of the cells with DIDS did not change the permeability of the erythrocyte membrane to K+, Rb+, and Cs+ to any significant extent. The experimental findings support the hypothesis that Li+ and Na+, but not K+, Rb+, and Cs+ form monovalent negatively charged ion pairs with CO3--, which traverse the membrane through the anion exchange system.


Assuntos
Membrana Eritrocítica/metabolismo , Eritrócitos/metabolismo , Metais Alcalinos/sangue , Ácido 4,4'-Di-Isotiocianoestilbeno-2,2'-Dissulfônico , Ácido 4-Acetamido-4'-isotiocianatostilbeno-2,2'-dissulfônico/análogos & derivados , Ácido 4-Acetamido-4'-isotiocianatostilbeno-2,2'-dissulfônico/farmacologia , Bicarbonatos/farmacologia , Transporte Biológico/efeitos dos fármacos , Permeabilidade da Membrana Celular/efeitos dos fármacos , Césio/sangue , Humanos , Técnicas In Vitro , Troca Iônica , Lítio/sangue , Potássio/sangue , Rubídio/sangue , Sódio/sangue
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