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1.
Lasers Med Sci ; 34(1): 35-40, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29980945

RESUMO

Iron molecule is of great importance in the synthesis of hemoglobin which is essential for oxygen transport. Iron levels are quantified by accurately high sensitivity tests, such as serum ferritin (SF). However, common studies to quantify SF are long and strenuous (~ 5 h), for example enzyme-linked immunosorbent assay (ELISA). In this paper, blood serum samples were analyzed by Raman spectroscopy (RS), and a computational analysis of spectra is proposed to detect differences in SF as an alternative procedure. Serum samples were obtained from 22 patients, 9 who were clinically diagnosed with anemia and 13 controls. Patients with anemia had low levels of SF (< 30 ng/ml), and a control group had levels between 30 and 500 ng/ml. The spectra obtained were conditioned with a baseline correction and smoothing, then evaluated by principal component analysis (PCA), and a predictive model was estimated by lineal discrimination analysis (LDA). The results showed a clear differentiation of the study groups by PCA, also 99.69% sensitivity and 100% specificity by LDA. This study suggest that Raman spectroscopy is a fast (~ 5 min) and a powerful tool capable to qualitative differentiate ferritin concentrations.


Assuntos
Ferritinas/sangue , Análise de Componente Principal , Análise Espectral Raman , Análise Discriminante , Humanos , Ferro , Curva ROC
2.
Int J Phytoremediation ; 16(7-12): 1073-86, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24933903

RESUMO

In order to gain knowledge on the potential use of Helianthus annuus L. for the remediation of Cr(VI) polluted waters, hydroponics experiments were set up to determine Cr uptake and tolerance in different Cr(VI)-sulfate conditions, and Cr biotransformations. Results indicated that Cr(VI) promoted seed germination, and plant tolerance was higher at younger plant stages. Cr uptake was dependent on sulfate concentrations. The highest Cr levels in roots and shoots (13,700 and 2,500 mg kg(-1) dry weight (DW), respectively) were obtained in 1 mM sulfate. The lowest Cr uptake in roots (10,600 mg kg(-1) DW) was observed in seedlings treated with no sulfate. In shoots, Cr concentration was of 1,500 mg kg(-1)DW for the 1 mM sulfate treatment, indicating a different level of interaction between chromate and sulfate in both tissues. For the first time, using micro X-ray florescence (muXRF), we demonstrated Cr reaches the root stele and is located in the walls of xylem vessels. Bulk and micro X-ray Absorption Near-Edge Structure (muXANES) results showed that Cr in the roots is mostly in the form of Cr(III) phosphate (80%), with the remainder complexed to organic acids. Our results suggest this plant species may serve for Cr(VI) rhizofiltration purposes.


Assuntos
Cromatos/toxicidade , Cromo/metabolismo , Helianthus/metabolismo , Poluentes da Água/metabolismo , Biodegradação Ambiental , Transporte Biológico , Cromo/análise , Cromo/toxicidade , Germinação/efeitos dos fármacos , Helianthus/efeitos dos fármacos , Helianthus/crescimento & desenvolvimento , Hidroponia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Espectrometria por Raios X , Sulfatos/farmacologia , Síncrotrons , Água/química , Poluentes da Água/análise , Poluentes da Água/toxicidade , Xilema/efeitos dos fármacos , Xilema/crescimento & desenvolvimento , Xilema/metabolismo
3.
World J Gastroenterol ; 14(37): 5707-11, 2008 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-18837088

RESUMO

AIM: To study the esophageal transit time (ETT) and compare its mean value among three anatomical inclinations of the body; and to analyze the correlation of ETT to body mass index (BMI). METHODS: A biomagnetic technique was implemented to perform this study: (1) The transit time of a magnetic marker (MM) through the esophagus was measured using two fluxgate sensors placed over the chest of 14 healthy subjects; (2) the ETT was assessed in three anatomical positions (at upright, fowler, and supine positions; 90 degrees , 45 degrees and 0 degrees , respectively). RESULTS: ANOVA and Tuckey post-hoc tests demonstrated significant differences between ETT mean of the different positions. The ETT means were 5.2 +/- 1.1 s, 6.1 +/- 1.5 s, and 23.6 +/- 9.2 s for 90 degrees , 45 degrees and 0 degrees , respectively. Pearson correlation results were r = -0.716 and P < 0.001 by subjects' anatomical position, and r = -0.024 and P > 0.05 according the subject's BMI. CONCLUSION: We demonstrated that using this biomagnetic technique, it is possible to measure the ETT and the effects of the anatomical position on the ETT.


Assuntos
Técnicas de Diagnóstico do Sistema Digestório , Esôfago/fisiologia , Trânsito Gastrointestinal , Magnetismo , Postura , Índice de Massa Corporal , Feminino , Humanos , Masculino , Processamento de Sinais Assistido por Computador , Decúbito Dorsal , Adulto Jovem
4.
Acta Gastroenterol Latinoam ; 38(4): 240-5, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19157378

RESUMO

BACKGROUND/AIMS: evidence of gender-related differences in gastric emptying have been reported in the literature. Usually, those researches have focusing only with solid or liquid meal and invasive techniques. The objective of this study was to know the differences in the half time of gastric emptying and frequency of peristaltic contractions measured with magnetogastrography (MGG) on healthy subjects, using a semi-solid test meal. METHODS: the study was carried out in 16 healthy subjects without gastrointestinal disease history they were divided in two groups, 8 male and 8 female. A test meal composed by 250 ml of yogurt and 3 grs of magnetite (Fe3O4), was employed. RESULTS: the gastric emptying half times were found to be 32.3 +/- 10.8 and 36.0 +/- 6.7 minutes, for men and women, respectively. Magnetogastrography modality presented in this study is a useful technique to measure the gastric emptying and the peristaltic contractions frequency. The studies were performed in healthy subjects without side effects. Using this technique a significant statistical difference (p<0.05) on gastric emptying from healthy volunteers was obtained between men and women. CONCLUSIONS: a contribution of this study was to demonstrate the feasibility of magnetogastrography to analyze gender differences in the gastric emptying half time using a semi-solid test meal.


Assuntos
Esvaziamento Gástrico/fisiologia , Trânsito Gastrointestinal/fisiologia , Adulto , Campos Eletromagnéticos , Eletrofisiologia , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Fatores Sexuais , Fatores de Tempo , Adulto Jovem
5.
Magn Reson Imaging ; 24(2): 195-200, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16455409

RESUMO

In this study, seven fruits have been tested on their magnetic properties, paramagnetic metal content and contrast enhancement in magnetic resonance imaging (MRI) of phantom and in vivo. Magnetic susceptibility was determined for the fruit pulps, as well as the contents of paramagnetic metals; iron, manganese and copper. The total content of these metals was 4.3, 8.6, 11.1, 10.9, 12.3, 8.3 and 29.3 mg/kg of fruit for plum, blueberry, apple (red), pineapple, beet, grape, blackberry, respectively, and with magnetic susceptibility of -2.29+/-0.07, -2.43+/-0.07, -2.13+/-0.07, -1.84+/-0.02, -1.75+/-0.01, -1.78+/-0.06, -2.18+/-0.07 SI, respectively. T(1)- and T(2)-weighted MR images were performed for the seven fruits and water (chi= -9.98 x 10(-3) SI) and in one subject. While there was no correlation between the magnetic susceptibility and contrast enhancement, there is a correlation with the total paramagnetic metal content determined with contrast enhancement in MRI. Thus, blackberry (Rubus spp.) contrast enhancement was the highest among the fruits in T(1)-weighted images. Furthermore, this fruit's contrast enhancement shows to be pH-dependent. These characteristics and the wide availability of the Rubus spp. suggest that it should be implemented as an oral contrast agent in images by MR to assess the function of the gastric section of the GI tract. Furthermore, it has the advantage of being a natural meal, so that it can be well tolerated by the patients and use as much as it is needed without side effects.


Assuntos
Meios de Contraste/administração & dosagem , Frutas , Gastroenteropatias/diagnóstico , Imageamento por Ressonância Magnética/métodos , Administração Oral , Humanos , Concentração de Íons de Hidrogênio , Imagens de Fantasmas
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