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1.
Sensors (Basel) ; 24(2)2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38257510

RESUMO

Seven increasing levels of water salinity from 0.029 to 0.600 M (as NaCl) were used to investigate the dependence of pH measurement, performed using colorimetric sensor arrays (CSAs), on ionic strength. The CSAs were arrays of sensing spots prepared in the form of sol-gel-embedding Bromothymol Blue (BB) and Bromocresol Green (BCG) in a porous nitrocellulose support. The support was impregnated over the entire thickness (≈100 µm), allowing for the signal (Hue) acquisition on the opposite side to the contact with the sample solution. Three CSAs were prepared, M1, M2, and M3. M1 contained a free cationic surfactant, hexadecyltrimethylammonium p-toluenesulfonate (CTApTs), for modulating the pKa of the indicators. In M2, the surfactant dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride (DTSACl) was covalently bonded to the sol-gel. M3 was prepared like M2 but using a larger amount of ethanol as the solvent for the synthesis. The modulation of the CTApTs or the DTSACl concentration enabled the tuning of the pKa. In general, the pKa modulation ability decreased with the increase in salinity. The presence of a surfactant covalently linked to the backbone partially reduced the competitiveness of the anionic species, improving the results. Nevertheless, the salt effect was still present, and a correction algorithm was required. Between pH 5.00 and 12.00, this correction could be made automatically by using spots taken as references to produce sensors independent of salinity. As the salt effect is virtually absent above 0.160 M, M2 and M3 can be used for future applications in seawater.

2.
Stat Methods Appt ; : 1-15, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36311812

RESUMO

Morbidity is one of the key aspects for assessing populations' well-being. In particular, chronic diseases negatively affect the quality of life in the old age and the risk that more years added to lives are years of disability and illness. Novel analysis, interventions and policies are required to understand and potentially mitigate this issue. In this article, we focus on investigating whether in Italy the compression of morbidity is in act in the recent years, parallely to an increase of life expectancy. Our analysis rely on large repeated cross-sectional data from the national surveillance system passi, providing deep insights on the evolution of morbidity together with other socio-demographical variables. In addition, we investigate differences in morbidity across subgroups, focusing on disparities by gender, level of education and economic difficulties, and assessing the evolution of these differences across the period 2013-2019.

3.
Sensors (Basel) ; 20(21)2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33114126

RESUMO

A pH colorimetric sensor array was prepared and characterized by combining tetrabromophenol blue (TBB) and bromothymol blue (BB) embedded in organically modified silicate (OrMoSil) spots polyvinylidene fluoride (PVDF)-supported. The signal was based on the Hue profile (H). The individual calibrations of TBB and BB showed precisions with minimum values of 0.012 pH units at pH = 2.196 for TBB and 0.018 at pH = 6.692 for BB. The overall precision of 10 spots of the mixture TBB/BB increased in the pH range of 1.000-8.000 from a minimum value of pH precision of 0.009 at pH = 2.196 to 0.012 at pH = 6.692, with the worst value of 0.279 pH units at pH = 4.101. The possibility to produce an array with much more than 10 spots allows for improving precision. The H analytical performance was compared to those of other color spaces such as RGB, Lab, and XYZ. H was the best one, with prediction error in the range of 0.016 to 0.021 pH units, at least three times lower than the second-best (x coordinate), with 0.064 pH units. These results were also confirmed by the calculation of the main experimental contributions to the pH prediction error, demonstrating the consistency of the proposed calculation approach.

4.
Neurol Sci ; 39(5): 835-839, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29445989

RESUMO

Parkinson's disease (PD) is a neurodegenerative disorder which affects the quality of life of patient and their family. Sleep disorders appear in 80-90% of PD patients and have a great impact on the PD well-being. We examined the relationship of patients' sleep quality and depression on burden, mood, quality of life, and quality of sleep of their caregivers. A multicenter, regional (Veneto), observational, cross-sectional study that included 55 patient-caregiver pairs was conducted. Patients were assessed using Parkinson's Disease Sleep Scale (PDSS) and Epworth Sleepiness Scale (ESS) for sleep disorders, Beck Depression Inventory (BDI) as a measure of depression, and Parkinson's Disease Questionnaire (PDQ-39) as a measure of quality of life. Caregivers were evaluated by the Caregiver Burden Inventory (CBI) a measure of burden, BDI, SF-36 Health Survey as measures of HRQoL, and Medical Outcomes Study-Sleep Scale (MOS-SS) for quality of sleep. CBI, HRQoL, MOS-SS, and BDI scores displayed no association with patients' age, cognition (Mini Mental State Examination (MMSE) and Frontal Assessment Battery (FAB)), disease duration, and Hoehn and Yahr (H&Y), and UPDRS III scales whereas were significantly correlated with patients' quality of sleep, depression, and quality life. CBI and HRQoL were also associated respectively with patients' ESS and L-dopa daily dose. This study underscores the presence of a significant relationship between patient and caregiver quality of life. Interestingly, sleep quality and depression rather than motor disability best predicted caregivers' well-being.


Assuntos
Cuidadores , Efeitos Psicossociais da Doença , Doença de Parkinson/complicações , Transtornos do Sono-Vigília/complicações , Idoso , Antiparkinsonianos/uso terapêutico , Cuidadores/psicologia , Estudos Transversais , Depressão/complicações , Depressão/terapia , Avaliação da Deficiência , Dopaminérgicos/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/psicologia , Doença de Parkinson/terapia , Qualidade de Vida , Sono , Transtornos do Sono-Vigília/psicologia , Transtornos do Sono-Vigília/terapia
5.
Genet Epidemiol ; 37(2): 205-13, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23307621

RESUMO

Biological plausibility and other prior information could help select genome-wide association (GWA) findings for further follow-up, but there is no consensus on which types of knowledge should be considered or how to weight them. We used experts' opinions and empirical evidence to estimate the relative importance of 15 types of information at the single-nucleotide polymorphism (SNP) and gene levels. Opinions were elicited from 10 experts using a two-round Delphi survey. Empirical evidence was obtained by comparing the frequency of each type of characteristic in SNPs established as being associated with seven disease traits through GWA meta-analysis and independent replication, with the corresponding frequency in a randomly selected set of SNPs. SNP and gene characteristics were retrieved using a specially developed bioinformatics tool. Both the expert and the empirical evidence rated previous association in a meta-analysis or more than one study as conferring the highest relative probability of true association, whereas previous association in a single study ranked much lower. High relative probabilities were also observed for location in a functional protein domain, although location in a region evolutionarily conserved in vertebrates was ranked high by the data but not by the experts. Our empirical evidence did not support the importance attributed by the experts to whether the gene encodes a protein in a pathway or shows interactions relevant to the trait. Our findings provide insight into the selection and weighting of different types of knowledge in SNP or gene prioritization, and point to areas requiring further research.


Assuntos
Seguimentos , Pesquisa em Genética , Polimorfismo de Nucleotídeo Único , Biologia Computacional/métodos , Estudo de Associação Genômica Ampla , Humanos , Metanálise como Assunto , Probabilidade
6.
Genet Epidemiol ; 37(2): 214-21, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23280596

RESUMO

Prioritization is the process whereby a set of possible candidate genes or SNPs is ranked so that the most promising can be taken forward into further studies. In a genome-wide association study, prioritization is usually based on the P-values alone, but researchers sometimes take account of external annotation information about the SNPs such as whether the SNP lies close to a good candidate gene. Using external information in this way is inherently subjective and is often not formalized, making the analysis difficult to reproduce. Building on previous work that has identified 14 important types of external information, we present an approximate Bayesian analysis that produces an estimate of the probability of association. The calculation combines four sources of information: the genome-wide data, SNP information derived from bioinformatics databases, empirical SNP weights, and the researchers' subjective prior opinions. The calculation is fast enough that it can be applied to millions of SNPS and although it does rely on subjective judgments, those judgments are made explicit so that the final SNP selection can be reproduced. We show that the resulting probability of association is intuitively more appealing than the P-value because it is easier to interpret and it makes allowance for the power of the study. We illustrate the use of the probability of association for SNP prioritization by applying it to a meta-analysis of kidney function genome-wide association studies and demonstrate that SNP selection performs better using the probability of association compared with P-values alone.


Assuntos
Teorema de Bayes , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único , Bases de Dados Genéticas , Humanos , Rim/fisiologia , Metanálise como Assunto , Modelos Genéticos , Probabilidade
7.
Food Chem ; 452: 139513, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38713982

RESUMO

The real-time monitoring of the pH values of alcoholic beverages was performed with a compact wireless device based on a colorimetric detection method with the Hue (H) as the analytical signal working in a pH range of 2.50-6.50. This device represents the first colorimetric pH meter reported in the literature monitoring in real-time the pH value of colored solutions. This pH meter consists of I) a nitrocellulose membrane impregnated with a pH-sensitive gel; II) a CCD camera for color acquisition; III) an electronic board with the calibration profiles of H vs. pH, and IV) a display to read the measured pH. It was applied to the pH determination of a white wine, a prosecco white wine, and a double malt beer leading to the values of pHwine= 3.30, pHprosecco= 3.33, pHbeer = 4.29. The analytical performance is comparable to the glass electrode with an accuracy error ≤ 0.05 pH units.


Assuntos
Cerveja , Colorimetria , Vinho , Vinho/análise , Cerveja/análise , Colorimetria/instrumentação , Colorimetria/métodos , Concentração de Íons de Hidrogênio
8.
ACS Sens ; 9(3): 1482-1488, 2024 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-38416572

RESUMO

A pH colorimetric sensor array (CSA) was prepared on a nitrocellulose membrane and used for accurate pH measurement in highly concentrated saline solutions. The CSAs consisted of sensing spots made of a suitable OrMoSil polymer prepared from organo-fluorinated-silane precursors and/or organosilane with tetraethyl orthosilicate hosting an acid-base indicator. Four CSAs were prepared: D, 1F, 2F, and 3F. In D, a nonfluorinated organosilane was present. From 1F to 3F, the concentration of the fluorinated organosilane increased and improved the pH measurement accuracy in highly saline concentrations. No recalibrations were required, and the analytical signal was stable in time. D, 1F, 2F, and 3F were deposited in triplicate, and they were prepared to work in the seawater pH interval (7.50-8.50). The use of fluorinated precursors led to a lower pH prediction error and tailored the interval of the CSA at more basic pH values so that the inflection points of the sigmoidal calibrations of D, 1F, 2F, and 3F moved from 6.97 to 7.98. The overall pH prediction error was 0.10 pH (1F), 0.02 pH (2F), and 0.04 pH units (3F). The CSAs were stable, reversible, reusable, and independent of salinity (S) between 20 and 40. The performances of the CSA were compared with those of a glass electrode, whose pHNIST values were converted in the pHSWS scale through a conversion equation. Being unaffected by the typical drawback of the glass electrode, the CSAs can be used directly in seawater real samples, and it validated the proposed conversion equation.


Assuntos
Colorimetria , Compostos de Organossilício , Concentração de Íons de Hidrogênio , Água do Mar , Eletrodos , Solução Salina
9.
Talanta ; 225: 122051, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33592773

RESUMO

The seawater pH measurement is usually quite complicated because that matrix is characterized by a high ionic strength leading to calibration errors if NIST standards are used. For this matrix, different pH scales like the "total hydrogen ion concentration scale" (TOT) and the "seawater scale" (SWS), are defined, and suitable synthetic seawater solutions must be prepared according to standard procedures to calibrate the glass electrode. This work provides a new approach to make seawater pH measurements by using the glass electrode calibrated with the NIST standards (pHNIST) converting the pHNIST into the right TOT or SWS scales by using empirical equations derived from theoretical thermodynamic data: pHTOT=pHNIST+0.10383+4.33⋅10-5TS+3.633⋅10-5T2-4.921⋅10-5S2, and pHSWS=pHNIST+0.097733+4.1059⋅10-5TS+3.5437⋅10-5T2-4.941⋅10-5S2, for the TOT and SWS scales, respectively. These equations are functions of two simple experimental parameters, namely, T = temperature (°C) and S = salinity (PSU, (g/L), Practical Salinity Units). These equations were experimentally validated and the uncertainty of pHTOT and pHSWS was demonstrated to have no statistical difference with the corresponding values obtained following the standard operative procedure (SOP) using commercially unavailable seawater-like buffers. The proposed method has therefore the same performances and it is largely preferable as it avoids long and tedious procedures of the synthetic seawater preparations.

10.
Talanta ; 213: 120840, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32200928

RESUMO

pH colorimetric sensors with prediction error comparable to the potentiometric measurements in the working range of the indicator employed, were prepared. Bromothymol Blue (BB), Tetrabromophenol Blue (TBB), Cresol Red (CR) and Brilliant Yellow (BY) in PVDF (Polyvinylidene Fluoride)-supported OrMoSil (organically modified silicate) matrix, were used. Sensor preparation was reproducible. Signal was based on a suitably modified Hue coordinate from HSV (Hue, Saturation, Value) color space, H. Although H profile was not influenced by the indicator concentrations, the prediction error depended on the product of saturation and luminance, Δ. By using H, the response of every spot was less affected by shape and optical inhomogeneity. The H calibration held for all the spots of the same lot and remained identical in time giving an advantage with respect to a glass electrode requiring calibration before each set of measurements. The prediction errors both in solution and in the OrMoSil matrix were similar: for BB, [Formula: see text]  = 0.03 in both environments; for TBB, [Formula: see text]  = 0.02 in the sensing spot and 0.05 in solution; for CR, [Formula: see text]  = 0.11 in the sensing spot and 0.04 in solution; for BY, [Formula: see text]  = 0.17 in the sensing spot and 0.07 in solution. Indeed, H values of TBB and BB increased their variances near the inflection point where Δ has the minimum value (heteroscedastic behavior).

11.
Talanta ; 212: 120739, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32113529

RESUMO

An in-depth study was conducted to determine the influence of some important parameters to produce a pH colorimetric sensor characterized by long-term stability, lack of leaching, high reversibility, repeatability and extended working range. Bromothymol Blue (BB) was used as pH sensitive molecule. Its performance was monitored while tailoring the concentration of some added cationic surfactants, together with the organic fraction of the sol-gel composition to avoid leaching phenomena, low homogeneity and to increase reversibility. Five cationic surfactants with different linear alkyl chain length (from C8 to C18) were added to a sol-gel containing BB. The C16 was chosen as optimal. The effect of the surfactant counterion was also investigated. The C16 surfactant had a pH working interval of 3 pH unit by using chloride, 1.5 with bromide and 1 pH unit with p-toluenesulfonate as counterions, respectively. Chloride was characterized by a larger inhomogeneity while p-toluenesulfonate gave homogeneity and high repeatability. The hexadecyltrimethylammonium p-toluenesulfonate was therefore chosen as the best surfactant. Leaching in alkaline medium was avoided by using the dodecyl moiety among three organic groups linked to the OrMoSil matrix (dodecyl, phenyl and methyl). Colorimetric sensor arrays made with these specifications remained stable and reversible for months.

12.
Talanta ; 219: 121251, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32887142

RESUMO

A pH colorimetric sensor array (CSA) with fast response time (<1 min) using only one acid-base indicator, Bromothymol Blue (BB), was prepared and characterized by modulating the amount, C, of the surfactant Hexadecyltrimethylammonium p-toluenesulfonate between 0 and 0.3725 gCTApTs/gprecursor with a constant amount of the OrMoSil precursors. The effect of the C increase is a continuous acidic shift of the calibration position, i.e. a huge variation of the pKa value of BB in the pH range 5.80-13.50. The precision error decreased with increasing C from 0.096 pH units (lower C values) to 0.023 pH units (larger C values). This result led to the development of a model to determine the number of spots with suitable C values required for having a similar value of precision in the entire working interval of the CSA. By selecting only 4 spots the precision error is < 0.100 pH units in the pH range 5.80-13.50. With 256 spots (diameter of each spot ≈ 3 mm), the model predicted an error almost constant (≈0.010) in the entire pH range.

14.
J Bras Nefrol ; 32(2): 195-200, 2010.
Artigo em Inglês, Português | MEDLINE | ID: mdl-21103679

RESUMO

OBJECTIVE: To study two different models of obesity, exocrine and endocrine, and its association on tail arterial pressure (TAP), body weight (BW), glucose metabolism and visceral fat content. METHODS: Male Wistar rats were studied. The MSG group was composed by rats that received of MSG in neonatal period. At the 3rd month of life, part of these animals received cafeteria diet. Animals received saline control in the neonatal period. In the 12 weeks of study, body weight and blood pressure were measured twice a week. In the end of this period on, Oral Glucose Tolerance Test (OGTT) was performed and the Insulin Sensitivity Index (ISI) was calculated, also the left Relative Ventricular Weight (RLW) and Relative Epididimal Fat Weight (REFW) were obtained. RESULTS: No changes on BW and TAP were verified. The obesity induced by MSG and CAF, individually, let to increases on insulin resistance (WST = 23,25 ± 9,31; CAF = 15,92 ± 9,10*; MSG = 13,41 ± 3,84* mg-1mU-1, p < 0,05 vs WST) and relative epididimal fat content (WST = 6,20 ± 0,57; CAF = 8,27 ± 1,53*; MSG = 8,23 ± 1,98* g/100 g, *p < 0,05) when these rats were compared to control rats. An enhanced effect upon these parameters was observed with the association of both obesity models (MSG+CAF = 9,34 ± 5,77 mg-1mU-1, p < 0,05 vs MSG and CAF) and visceral fat content (MSG+CAF = 11,12 ± 3,85 g/100g, p < 0,05 vs MSG and CAF). CONCLUSION: The association of these two experimental models of obesity aggravates insulin resistance that probably is due at least in part to the increase of visceral fat content.


Assuntos
Pressão Sanguínea , Glucose/metabolismo , Obesidade/metabolismo , Obesidade/fisiopatologia , Cauda/irrigação sanguínea , Animais , Glândulas Exócrinas , Masculino , Sistemas Neurossecretores , Obesidade/etiologia , Ratos , Ratos Wistar
15.
J. bras. nefrol ; 32(2): 195-200, abr.-jun. 2010. graf, tab
Artigo em Inglês, Português | LILACS | ID: lil-551677

RESUMO

OBJETIVO: Estudar dois modelos de obesidade, exócrina e endócrina, e sua associação sobre a pressão arterial de cauda (PAC), o peso corporal (PC), o metabolismo glicídico (ISI) e gordura epididimal relativa (GER). MÉTODOS: Foram estudados ratos machos da cepa Wistar. O grupo MSG recebeu glutamato monossódico no período neonatal. Aos 3 meses de idade parte desses animais passou a receber dieta cafeteria (CAF). Os animais receberam controle salina no período neonatal. Durante 12 semanas foram pesados (PC) e tiveram a pressão arterial de cauda (PAC) aferida. O Teste de Tolerância Oral à Glicose foi realizado e o Índice de Sensibilidade à Insulina (ISI), calculado. O peso ventricular relativo (PVR) e a gordura epididimal relativa (GER) também foram calculados. RESULTADOS: Não se verificou alterações no PC e na PAC. A obesidade induzida pela administração de MSG e CAF, isoladamente, promoveu aumento da resistência à insulina (WST = 23,25 ± 9,31; CAF = 15,92 ± 9,10*; MSG = 13,41 ± 3,84* mg-1mU-1, p < 0,05 vs WST) e da gordura visceral (WST = 6,20 ± 0,57; CAF = 8,27 ± 1,53*; MSG = 8,23 ± 1,98* g/100 g, *p < 0,05), quando esses animais foram comparados com os controles. A associação de ambos os modelos de obesidade produziu um efeito sinérgico sobre a resistência à insulina (MSG+CAF = 9,34 ± 5,77 mg-1mU-1, p<0,05 vs MSG e CAF) e sobre o conteúdo de gordura visceral (MSG+CAF = 11,12 ± 3,85 g/100g, p < 0,05 vs MSG e CAF). CONCLUSÃO : A associação de dois modelos de obesidade agrava a resistência à insulina e esse fato pode ser atribuído pelo menos em parte ao aumento da GER.


OBJECTIVE: To study two different models of obesity, exocrine and endocrine, and its association on tail arterial pressure (TAP), body weight (BW), glucose metabolism and visceral fat content. METHODS: Male Wistar rats were studied. The MSG group was composed by rats that received of MSG in neonatal period. At the 3rd month of life, part of these animals received cafeteria diet. Animals received saline control in the neonatal period. In the 12 weeks of study, body weight and blood pressure were measured twice a week. In the end of this period on, Oral Glucose Tolerance Test (OGTT) was performed and the Insulin Sensitivity Index (ISI) was calculated, also the left Relative Ventricular Weight (RLW) and Relative Epididimal Fat Weight (REFW) were obtained. RESULTS: No changes on BW and TAP were verified. The obesity induced by MSG and CAF, individually, let to increases on insulin resistance (WST = 23,25 ± 9,31; CAF = 15,92 ± 9,10*; MSG = 13,41 ± 3,84* mg-1mU-1, p < 0,05 vs WST) and relative epididimal fat content (WST = 6,20 ± 0,57; CAF = 8,27 ± 1,53*; MSG = 8,23 ± 1,98* g/100 g, *p < 0,05) when these rats were compared to control rats. An enhanced effect upon these parameters was observed with the association of both obesity models (MSG+CAF = 9,34 ± 5,77 mg-1mU-1, p < 0,05 vs MSG and CAF) and visceral fat content (MSG+CAF = 11,12 ± 3,85 g/100g, p < 0,05 vs MSG and CAF). CONCLUSION: The association of these two experimental models of obesity aggravates insulin resistance that probably is due at least in part to the increase of visceral fat content.


Assuntos
Animais , Masculino , Ratos , Pressão Sanguínea , Glucose/metabolismo , Obesidade/metabolismo , Obesidade/fisiopatologia , Cauda/irrigação sanguínea , Glândulas Exócrinas , Sistemas Neurossecretores , Obesidade/etiologia , Ratos Wistar
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