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1.
Phys Chem Chem Phys ; 25(40): 26999-27007, 2023 Oct 18.
Article in English | MEDLINE | ID: mdl-37728416

ABSTRACT

Improving the performance of thin film-based devices is a crucial factor for their successful application, mainly for organic electronic semiconductors. The adjustment of supramolecular structuring of thin films plays a role in the optical and electrical properties. In this sense, we investigated how various pH values, such as 2.5, 6.0, and 9.0, of the solutions influenced the growth of iron tetrasulfonated phthalocyanine (FeTsPc) Layer-by-Layer (LbL) films and their respective supramolecular structures as well as their electrochemical properties. The supramolecular structures were evaluated via UV-vis absorption spectroscopy, quartz crystal microbalance (QCM), micro-Raman spectroscopy, Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and cyclic voltammetry. The different pH values of the solution induce different degrees of molecular aggregation for FeTsPc (monomer, dimer, and aggregate formation). For instance, the higher the pH, the higher the aggregation. Films produced at pH 2.5 were organized preferentially with the molecules perpendicular to the substrate, while films at pH 6.0 and 9.0 were organized preferentially with the molecules parallel to the substrate. Besides, the film produced at pH 2.5 results in higher film thickness, higher stability, and better electrocatalytic behavior for the electrochemical detection of catechol. The results presented here enhance the understanding of nanostructured films, helping to harness supramolecular organization to improve the performance of thin-film devices.

2.
PLoS One ; 16(6): e0252578, 2021.
Article in English | MEDLINE | ID: mdl-34077473

ABSTRACT

BACKGROUND: We performed a systematic review of studies conducted in Latin America and the Caribbean (LAC) to assess the impact of oral diseases on oral health-related quality of life (OHRQoL). MATERIALS AND METHODS: Searches were performed of the following PubMed, EMBASE, CINAHL, Scopus, and LILACS databases. Randomized clinical trials, quasi-experimental studies, cohort studies, case and control studies, and cross-sectional studies which included at least 100 participants evaluating the impact of oral diseases on OHRQoL were included. PROSPERO registry number: CRD42020156098. RESULTS: After exclusion of duplicates, 3310 articles were identified, 40 of which were included in this review. 90% of the studies were conducted in Brazil. The most commonly used OHRQoL measuring instruments were CPQ 11-14 (n = 9), ECOHIS (n-8) and B-ECOHIS (n = 8). The study designs included 32 cross-sectional, 2 cohort and 6 case and control studies. Most of the studies were conducted in children (n = 25) and adolescents (n = 9). Most studies identified an impact on OHRQoL in children, adolescents and adults with oral diseases. Moreover, greater oral disease severity had a greater impact on OHRQoL. CONCLUSIONS: Most studies in LAC report a negative impact of diseases on OHRQoL. More longitudinal studies are required to confirm the results of these studies.


Subject(s)
Oral Health/statistics & numerical data , Adolescent , Adult , Aged , Aged, 80 and over , Caribbean Region , Case-Control Studies , Child , Child, Preschool , Cohort Studies , Cross-Sectional Studies , Humans , Infant , Latin America , Middle Aged , Quality of Life , Surveys and Questionnaires
3.
Biomater Sci ; 7(6): 2511-2519, 2019 May 28.
Article in English | MEDLINE | ID: mdl-30968104

ABSTRACT

Herein, we demonstrate the use of lysozyme (Lys) as a model to fabricate a protein carrier system based on gold nanoparticles (AuNPs) via the Layer-by-Layer (LbL) technology. Poly(ethyleneimine) (PEI) and poly(sodium 4-styrenesulfonate) (PSS) were used as cationic and anionic polymers respectively to grow oppositely charged layers. Mild aqueous conditions were utilized to avoid protein denaturation and activity instead of organic solvents that have been used in other encapsulation systems. Two different strategies were used: (A) lysozyme acting as a reducing and stabilizing agent in the formation of AuNPs at a temperature of 45 ± 2 °C followed by only two subsequent polymeric layers deposited by LbL, and (B) citrate acting as a reducing agent prior to stabilization of the AuNPs by mercaptoundecanoic acid. Dynamic light scattering, UV-vis spectroscopy, IR spectroscopy and transmission electron microscopy were used to characterize the nanoconjugates. Furthermore, the enzymatic activity of the resulting protein/nanoparticle conjugates was evaluated using the bacteria Micrococcus lysodeikticus as a substrate.


Subject(s)
Biocompatible Materials/chemistry , Gold/chemistry , Metal Nanoparticles/chemistry , Muramidase/chemistry , Biocompatible Materials/chemical synthesis , Chemistry Techniques, Synthetic , Citric Acid/chemistry , Micrococcus/enzymology , Models, Molecular , Molecular Conformation , Muramidase/metabolism , Polyethyleneimine/chemistry , Polystyrenes/chemistry , Temperature
4.
Front Chem ; 6: 131, 2018.
Article in English | MEDLINE | ID: mdl-29740576

ABSTRACT

The maturity of grapes is usually monitored by means of the sugar concentration. However, the assessment of other parameters such as the phenolic content is also important because the phenolic maturity has an important impact on the organoleptic characteristics of wines. In this work, voltammetric sensors able to detect phenols in red grapes have been developed. They are based on metal oxide nanoparticles (CeO2, NiO, and TiO2,) whose excellent electrocatalytic properties toward phenols allows obtaining sensors with detection limits in the range of 10-8 M and coefficients of variation lower than 7%. An electronic tongue constructed using a combination of the nanoparticle-based sensors is capable to monitor the phenolic maturity of red grapes from véraison to maturity. Principal Component Analysis (PCA) can be successfully used to discriminate samples according to the ripeness. Regression models performed using Partial Least Squares (PLS-1) have established good correlations between voltammetric data obtained with the electrochemical sensors and the Total Polyphenolic Index, the Brix degree and the Total Acidity, with correlation coefficients close to 1 and low number of latent variables. An advantage of this system is that the electronic tongue can be used for the simultaneous assessment of these three parameters which are the main factors used to monitor the maturity of grapes. Thus the electronic tongue based on metal oxide nanoparticles can be a valuable tool to monitor ripeness. These results demonstrate the exciting possible applications of metal oxide nanoparticles in the field of electronic tongues.

5.
Article in English | MEDLINE | ID: mdl-27826547

ABSTRACT

The quality of wines is usually evaluated by a sensory panel formed of trained experts or traditional chemical analysis. Over the last few decades, electronic noses (e-noses) and electronic tongues have been developed to determine the quality of foods and beverages. They consist of arrays of sensors with cross-sensitivity, combined with pattern recognition software, which provide a fingerprint of the samples that can be used to discriminate or classify the samples. This holistic approach is inspired by the method used in mammals to recognize food through their senses. They have been widely applied to the analysis of wines, including quality control, aging control, or the detection of fraudulence, among others. In this paper, the current status of research and development in the field of e-noses and tongues applied to the analysis of wines is reviewed. Their potential applications in the wine industry are described. The review ends with a final comment about expected future developments.

6.
J Am Soc Nephrol ; 26(1): 220-9, 2015 Jan.
Article in English | MEDLINE | ID: mdl-24970885

ABSTRACT

Diabetic kidney disease (DKD) is the leading cause of ESRD. We conducted an open-label, prospective, randomized trial to determine whether pentoxifylline (PTF), which reduces albuminuria, in addition to renin-angiotensin system (RAS) blockade, can slow progression of renal disease in patients with type 2 diabetes and stages 3-4 CKD. Participants were assigned to receive PTF (1200 mg/d) (n=82) or to a control group (n=87) for 2 years. All patients received similar doses of RAS inhibitors. At study end, eGFR had decreased by a mean±SEM of 2.1±0.4 ml/min per 1.73 m(2) in the PTF group compared with 6.5±0.4 ml/min per 1.73 m(2) in the control group, with a between-group difference of 4.3 ml/min per 1.73 m(2) (95% confidence interval [95% CI], 3.1 to 5.5 ml/min per 1.73 m(2); P<0.001) in favor of PTF. The proportion of patients with a rate of eGFR decline greater than the median rate of decline (0.16 ml/min per 1.73 m(2) per month) was lower in the PTF group than in the control group (33.3% versus 68.2%; P<0.001). Percentage change in urinary albumin excretion was 5.7% (95% CI, -0.3% to 11.1%) in the control group and -14.9% (95% CI, -20.4% to -9.4%) in the PTF group (P=0.001). Urine TNF-α decreased from a median 16 ng/g (interquartile range, 11-20.1 ng/g) to 14.3 ng/g (interquartile range, 9.2-18.4 ng/g) in the PTF group (P<0.01), with no changes in the control group. In this population, addition of PTF to RAS inhibitors resulted in a smaller decrease in eGFR and a greater reduction of residual albuminuria.


Subject(s)
Albumins/analysis , Diabetic Nephropathies/drug therapy , Diabetic Nephropathies/urine , Kidney/drug effects , Pentoxifylline/therapeutic use , Aged , Diabetes Mellitus, Type 2/complications , Disease Progression , Female , Glomerular Filtration Rate , Humans , Inflammation , Male , Middle Aged , Prospective Studies , Research Design , Treatment Outcome
7.
J Clin Pharmacol ; 53(4): 421-6, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23426718

ABSTRACT

Inflammation is a strong predictor of increased morbidity and mortality in hemodialysis (HD) patients. Paricalcitol, a selective vitamin D receptor activator used for prevention and treatment of secondary hyperparathyroidism, has shown anti-inflammatory properties in experimental studies, although clinical data are scarce. In an open-label, prospective, single center, pilot study, 25 stable HD patients, previously receiving calcitriol, completed 12 weeks of therapy with oral paricalcitol. Serum and peripheral blood mononuclear cell (PBMC) expression profiles of inflammatory cytokines were analyzed. Serum interleukin (IL)-1, IL-10, and IL-18 did not change, unlike high-sensitivity C-reactive protein (hs-CRP), tumor necrosis factor-α (TNF-α), and IL-6, which experienced a significant mean percent decrease of 14.3%, 4.7%, and 5%, respectively. There was a significant reduction in the TNF-α/IL-10 and the IL-6/IL-10 ratios (P < .05). Serum intact parathyroid hormone concentration experienced a mild but significant reduction. In addition, expression levels of TNF-α and IL-6 decreased by 19.1% (P < .01) and 17.5% (P < .001), respectively, whereas expression of IL-10 increased by 17.7% (P < .01) after treatment. In conclusion, paricalcitol administration to HD patients is associated with a beneficial effect on the inflammatory cytokine serum and gene expression profile of PBMC. This effect may contribute to the survival benefits of paricalcitol observed in clinical studies.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Ergocalciferols/pharmacology , Renal Dialysis , Administration, Oral , Aged , Cytokines/blood , Cytokines/genetics , Female , Humans , Leukocytes, Mononuclear/drug effects , Leukocytes, Mononuclear/metabolism , Male , Middle Aged , Parathyroid Hormone/blood , Phosphates/blood , Pilot Projects , Prospective Studies , RNA, Messenger/metabolism
8.
Phys Chem Chem Phys ; 9(18): 2266-73, 2007 Jun 14.
Article in English | MEDLINE | ID: mdl-17487324

ABSTRACT

Here we report on the electroactivity properties of Langmuir-Blodgett (LB) films of the hole-transport molecule 4,4',4''-tris[3-methylphenyl(phenyl)amino] triphenylamine (m-MTDATA). Fairly stable Langmuir films at the air-water interface are accomplished, despite the non-amphiphilic character of the molecule. The reflection-absorption infrared spectroscopy (RAIRS) and Fourier transform infrared (FT-IR) analysis revealed that the molecules arrange with no neat preferential orientation, in agreement with the amorphous glassy nature of this starburst molecule. However, there is a tendency of the molecules to organize in a more planar conformation due to the intermolecular stacking induced by the LB technique. On the other hand, the fundamental electrochemistry (by cyclic voltammetry, CV) of the films is also analyzed. The CV studies of both solution and films reveal that both the solid state and the electrolyte's anions clearly affect the m-MTDATA's electroactivity, exhibiting a unique and broad redox process instead of the two reversible oxidations observed in solution. The oxidization mechanism is discussed. Finally, the spectroelectrochemistry studies evidence that the oxidization of the films leads to new absorption bands, among which the emerging bands in the NIR region ascribed to intervalence charge transfer (IVCT) between the generated aminyl radical cations should be pointed out.


Subject(s)
Aniline Compounds/chemistry , Chlorates/chemistry , Electrochemistry , Models, Molecular , Molecular Structure , Oxidation-Reduction , Solutions/chemistry , Spectroscopy, Fourier Transform Infrared , Surface Properties
9.
Langmuir ; 23(7): 3712-22, 2007 Mar 27.
Article in English | MEDLINE | ID: mdl-17316034

ABSTRACT

Hydroxygallium phthalocyanine (HOGaPc) and cellulose (from a trimethylsilyl derivative) have been used as native elements for the preparation of a novel family of hybrid films. By spin-coating, both components allow the building of films with different configurations on various substrates in a controlled way. The particularities of these hybrid films have been characterized by a range of techniques such as Fourier transform infrared spectroscopy (FTIRS) in attenuated total reflection using multiple internal reflections (ATR/MIR), absorption ultraviolet and visible spectroscopy (UV-vis), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and surface potential measurements using the Kelvin-Zisman vibrating capacitor probe (KP). This enabled determination of the influence of cellulose on the arrangement of HOGaPc and, consequently, control of the relation between the structure and the properties of the films. Finally, gas sensor tests were performed to check the potentialities of these hybrid films. In particular, the synergetic behavior between the film-forming materials allows a fast and sensible change in surface potential after cyclic exposures to ozone (O3, 100 ppb) and nitrogen. Overall, we present the advantages of combining phthalocyanine with cellulose in enhancing the properties of the final product. Introduction of cellulose as a host material opens up a new area of hybrid films.

10.
Rev. cuba. obstet. ginecol ; 2(4): 315-20, oct. -dic. 1976.
Article in Spanish | CUMED | ID: cum-6871

ABSTRACT

Se mencionan los patrones de clasificación utilizados, las indicaciones que motivaron el empleo de la cardiotacografía, los hallazgos encontrados en la interpretación de los registros obtenidos en la hora que precedióal parto y la relación existente entre "dips" umbilicales, presencia de circulares y estado del recién nacido (así como la presencia de "dips" tardíos y estado del recién nacido) al minuto de vida, valorado por la puntuación de Apgar (AU)


Subject(s)
Heart Rate , Fetal Distress , Fetal Monitoring
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