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1.
J Conserv Dent Endod ; 27(7): 685-694, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39262603

RESUMO

This systematic review evaluated the role of Potassium-titanyl-phosphate (KTP) lasers in dental bleaching by comparing tooth color change and rise in intrapulpal temperature after bleaching with KTP, Neodymium-doped yttrium aluminum garnet (Nd:YAG), Er:YAG, and diode laser system. Following were the inclusion criteria: in vitro studies in English available in full text. Articles published between 2000 and 2021 were selected. The search for was conducted on PubMed, Cochrane library/CENTRAL, Wiley online library, ProQuest, Science Direct, and Hand searching/specialized registers. Keywords were used: "Lasers" [Mesh] and "Tooth bleaching" [Mesh] using Boolean operators. A total of four articles fulfilled the inclusion criteria. The quality assessment of studies included was undertaken independently as part of data extraction process. KTP lasers demonstrated more effectiveness in attaining color change in stained teeth and showed the lowest rise in intrapulpal temperature. Based on the data obtained in the present review, the choice of bleaching treatment is directly related to the type of discoloration, activation of the bleaching agent, and esthetic requirement. Although all bleaching procedures were effective in color change, the KTP laser showed better results when compared to other laser activation. The bleaching treatment protocol is directly related to the type of discoloration, activation of the bleaching agent, and esthetic requirement. It has been demonstrated that a faster change in color can be obtained when bleaching is performed in combination with a light source, i.e., power bleaching aiming for a more in-depth change of color.

2.
Talanta ; 281: 126925, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39305765

RESUMO

On-site quantitative detection of organophosphorus pesticides (OPs) is crucial for safeguarding food and public safety. This study presents a novel acetylcholinesterase (AChE)-mediated paper-based Au3+-etching of gold nanobipyramids (AuNBPs) system. The system employs a long-term storable AuNBPs-deposited nylon membrane embedded within a portable and temperature-controlled paper-based analytical device. This system, coupled with a colorimeter-based quantitative method, enables the development of a practical paper-based multicolor sensor (PMS) for on-site quantitative detection of three common OPs (paraoxon, dichlorvos, and trichlorfon). In the absence of OPs, AChE hydrolyzes acetylthiocholine to thiocholine, which reduces Au3+ to Au+. The presence of OPs inhibits AChE activity, thereby preserving Au3+ to etch AuNBPs on nylon membranes, accompanied by multicolor changes. These color changes can be simply quantified by measuring the a∗ parameter of the CIELab color space using a portable colorimeter. Under optimal conditions, the PMS displayed eight OPs-corresponding color changes with a minimum detectable concentration of 1.0-10 µg/L (visual observation) and limits of detection of 0.8-7.2 µg/L (colorimeter) and 0.2-3.4 µg/L (UV-vis spectrometry). The PMS successfully determined the OPs in vegetable and rice samples with recoveries of 89.0-109 % and RSDs (n = 5) of <6 %. These results were consistent with those obtained using the HPLC-MS method. The PMS demonstrates excellent portability, AuNBPs stability, detection sensitivity, and reproducibility, making it a promising tool for the on-site quantitative detection of OPs residues in food. Furthermore, the paper-based etching system coupled with the colorimeter-based quantitative method provides a valuable reference to develop practical PMSs for various targets in diverse fields.

3.
J Esthet Restor Dent ; 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39189147

RESUMO

OBJECTIVE: This article aims to demonstrate the clinical application of a comprehensive workflow that integrates digital tools for accurate color matching, and its immediate implementation in the restoration of anterior teeth. CLINICAL CONSIDERATIONS: Two patients demonstrating dissatisfaction regarding a maxillary central incisor had an old restoration replaced resorting to a digital workflow to enhance the predictability of the new direct restoration. OptiShade allowed the precise assessment of tooth color and the CompoShade application provided precise color and material selection, as well as the determination of a layering strategy. Precision and accuracy of the colorimeter and the composite layering application were demonstrated clinically in vivo. CONCLUSIONS: Implementing a digital workflow with the integration of OptiShade measurements and the CompoShade layering recipe calculation, as well as the respective realistic try-in, enables the achievement of precise color matching for anterior composite restorations. CLINICAL SIGNIFICANCE: The employment of a digital colorimeter and layering recipes simplify shade matching, and optimizes composite resin clinical use and success. The implementation of a realistic try-in, previous to the definitive restoration, allows the clinician to perform any adjustments if needed.

4.
J Funct Biomater ; 15(8)2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39194666

RESUMO

Multilayer monolithic zirconia, which incorporates polychromatic layers that mimic natural tooth gradients, offers enhanced aesthetics and functionality while reducing debonding risks and improving fabrication efficiency. However, uncertainties remain regarding the fracture characteristics of multilayer monolithic zirconia crowns under occlusal loading, whether composed of uniform or combined yttria levels. The current study investigated how variations in yttria levels and thicknesses affected the optical properties and fracture loads of multilayer monolithic zirconia. Samples of multilayer monolithic zirconia in the Vita A1 shade were used, while employing 3Y (SZ) and 4Y + 5Y (AZ) yttria levels. The optical properties, including the color difference (ΔEWS) and translucency parameters (TP00), were measured using a digital colorimeter. The fracture loads were analyzed using a universal testing machine, and fractured surfaces were examined under a stereomicroscope. Statistical analyses assessed the impacts of the yttria levels and sample thicknesses on the optical properties. The ΔEWS values of SZ ranged 3.6 to 4.0, while for AZ, ΔEWS at 0.5 mm was 3.9 and <2.6 for other thicknesses. The TP00 values decreased with an increased thickness, with AZ generally exhibiting greater translucency than SZ. In the fracture load investigations, SZ (>1600 N) generally exceeded AZ (>1260 N), with fracture loads notably increasing with thickness, particularly for premolars (SZ > 3270 N, AZ > 2257 N). SZ predominantly exhibited partial and complete fractures, whereas AZ showed fewer non-fracture categorizations. Complete fractures began with dense, irregular cracks that extended outward to reveal smooth surfaces, while premolars subjected to higher loads exhibited concentric ripple-like structures. Partial fractures revealed radial textures indicative of areas of stress concentration. In summary, higher yttria levels were correlated with increased translucency, while variations in the fracture loads primarily stemmed from differences in the tooth position or thickness. Overall, multilayer monolithic zirconia incorporating combined yttria levels of 4Y + 5Y (AZ) offered high translucency, precise color matching, and substantial fracture resistance, rendering it highly suitable for aesthetic and functional dental applications.

5.
Int J Clin Pediatr Dent ; 17(3): 274-278, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-39144518

RESUMO

Physical development and growth are significantly influenced by adequate nutrition. Enamel, dentin, and dental pulp are among the tissues that contain iron, which is regarded as a necessary element for human health. The disadvantages of the available iron drops include bad taste and black discoloration of primary teeth. In areas that are decalcified and hypomineralized, this discoloration is more noticeable. Therefore, efforts are being made to create iron drops that have a more pleasant taste and minimal adverse effects (i.e., no or minimal tooth discoloration). Liposomes are minuscule vesicles made of the bilayer of phospholipids that can encase both hydrophilic and hydrophobic drugs to boost their effectiveness and lessen side effects (color staining). Therefore, the goal of the study is to compare the color stability of cosmetic materials with that of pediatric liposomal iron supplements and regular pediatric iron supplements. How to cite this article: Lokhande RS, PJ N, Deoghare A,et al. Effect of Different Iron Supplements on Color Stability of Nanocomposite Restorative Materials. Int J Clin Pediatr Dent 2024;17(3):274-278.

6.
J Conserv Dent Endod ; 27(5): 552-555, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38939539

RESUMO

Objective: The purpose of this study is to comparatively evaluate the effect of discoloration of nanohybrid composite by four different phytopigments. Materials and Methods: Fifty disk-shaped samples of nanohybrid (3M Filtek Z350) resin composites were prepared using an acrylic template of dimension 5 mm × 3 mm. They were randomly divided into five groups and immersed in solutions of tomato powder, beetroot powder, java plum powder, and turmeric powder. Distilled water was used as the control group. The samples were placed in respective solutions for 3 h daily and stored in artificial saliva for the rest of the day for 28 days. Color values (L*, a*, b*) were measured by colorimeter using the CIE L*a*b* system at the end of the 7th and 28th days of immersion. Color differences ΔE*ab were statistically analyzed. Results: All the samples showed a change in color of nanohybrid composite resin to varying degrees. The mean ΔE*ab value obtained with beetroot solution was the highest among all the groups at the end of the 7th and 28th days, depicting that beetroot solution showed maximum mean color variation, followed by java plum solution, turmeric solution, and tomato solution. Conclusion: All the phytopigments used in this study have the potential to discolor the nanohybrid composite resin, with beetroot causing the most severe discoloration.

7.
Plant Methods ; 20(1): 78, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38812007

RESUMO

BACKGROUND: Red raspberry fruit color is a key driver of consumer preference and a major target of breeding programs worldwide. Screening for fruit color typically involves the determination of anthocyanin content and/or the assessment of color through a colorimeter. However, both procedures are time-consuming when the analyses involve hundreds or thousands of samples. The objectives of this study were to develop a high-throughput method for red raspberry puree color measurement and to test the correlations between color parameters and total anthocyanin content. Color coordinates were collected with a colorimeter on 126 puree samples contained in Petri dishes and with the Tomato Analyzer Color Test (TACT) module to assess the same samples prepared in Petri dishes and in 96-well plates. An additional 425 samples were analyzed using only 96-well plates. Total anthocyanins were extracted from all 551 samples. RESULTS: Regression models for L*, a*, b* measured with the colorimeter and TACT using Petri dishes were all significant (p < 0.001), but very consistent only for L* (R2 = 0.94). Significant (p < 0.001) and very consistent regressions (R2 = 0.94 for L* and b*, R2 = 0.93 for a*) were obtained for color parameters measured with TACT using Petri dishes and TACT using plates. Of the color parameters measured with the colorimeter, only L*, a*/b*, and hue significantly correlated with total anthocyanins (p < 0.05), but, except for L* (R = - 0.79), the correlations were weak (R = - 0.23 for a*/b* and R = 0.22 for hue). Conversely, all correlations with total anthocyanins and color parameters measured with TACT were significant (p < 0.001) and moderately strong (e.g., R = - 0.69 for L* and R = 0.55 for a*/b*). These values were indicative of darker colors as total anthocyanin content increased. CONCLUSIONS: While the colorimeter and TACT-based methods were not fully interchangeable, TACT better captured color differences among raspberry genotypes than the colorimeter. The correlations between color parameters measured with TACT and total anthocyanins were not strong enough to develop prediction models, yet the use of TACT with 96-well plates instead of Petri dishes would enable the high-throughput measurement of red raspberry puree color.

8.
J Dent ; 145: 105023, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38670331

RESUMO

OBJECTIVES: Multilayer monolithic zirconia (M-Zr) crowns can be engineered to achieve gradational translucency and color intensity. However, this modification may compromise the mechanical strength, raising concerns regarding the ability of M-Zr crowns to withstand occlusal stresses. The effects of M-Zr crown thickness on translucency and ability to endure occlusal forces were investigated at different tooth positions (incisors, premolars, and molars). The objective was to determine the minimal thickness of M-Zr crowns used in tooth preparation to meet aesthetic and functional demands. METHODS: M-Zr samples (Vita A1) with four thicknesses (0.5, 1.0, 1.5, and 2.0 mm) were prepared and subjected to translucency testing using a digital colorimeter by 3-third and 9-square division methods. Crown-shaped M-Zr samples with three thicknesses (1.0, 1.5, and 2.0 mm) and three tooth positions (incisor, premolar, and molar) were digitally designed, and 2.0 mm metal abutments were fabricated. The samples were bonded to the abutments; their fracture characteristics were evaluated using a universal testing machine, and their fracture surfaces examined using an optical microscope. Statistical analyses included the Shapiro-Wilk test, Pearson correlation, and one-way and two-way ANOVA with a post hoc Tukey HSD test (α = 0.05). RESULTS: Color analysis results revealed a significant negative correlation between thickness and translucency (r < -0.96, P < 0.01), with the highest values in the incisal region. Cross-sectional profiles confirmed the uniform thickness and morphology of the digitally designed M-Zr crowns. The results of fracture strength analysis showed position-dependent variability, a strong positive correlation with thickness (r > 0.96, P < 0.01), and fracture strengths consistently exceeding 1200 N across all tooth positions. Fracture patterns indicated that thinner crowns at the incisors and molars were more prone to cracking, whereas those at the premolars demonstrated significantly higher strength (4872.51 N, P < 0.05), only with crack or even no fracture occurring at 2.0 mm. CONCLUSIONS: Thickness significantly influenced both the translucency and fracture strength of M-Zr, with the tooth position playing an additional role, albeit to a lesser extent. Although thinner crowns exhibited lower strength at each tooth position, even at a thickness of 1.0 mm, fracture strength exceeding 1200 N was maintained, surpassing the typical occlusal forces. Thus, it can be asserted that M-Zr crowns with a minimum thickness of 1.0 mm can meet both aesthetic and functional requirements.


Assuntos
Dente Pré-Molar , Coroas , Materiais Dentários , Planejamento de Prótese Dentária , Teste de Materiais , Zircônio , Zircônio/química , Humanos , Materiais Dentários/química , Propriedades de Superfície , Dente Molar , Análise do Estresse Dentário , Falha de Restauração Dentária , Cor , Dente Suporte , Força de Mordida , Incisivo , Porcelana Dentária/química , Estresse Mecânico
9.
Talanta ; 274: 126006, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38569371

RESUMO

This study proposes an efficient method for monitoring the submerged fermentation process of Tremella fuciformis (T. fuciformis) by integrating electronic nose (e-nose), electronic tongue (e-tongue), and colorimeter sensors using a data fusion strategy. Chemometrics was employed to establish qualitative identification and quantitative prediction models. The Pearson correlation analysis was applied to extract features from the e-nose and tongue sensor arrays. The optimal sensor arrays for monitoring the submerged fermentation process of T. fuciformis were obtained, and four different data fusion methods were developed by incorporating the colorimeter data features. To achieve qualitative identification, the physicochemical data and principal component analysis (PCA) results were utilized to determine three stages of the fermentation process. The fusion signal based on full features proved to be the optimal data fusion method, exhibiting the highest accuracy across different models. Notably, random forest (RF) was shown to be the most accurate pattern recognition method in this paper. For quantitative prediction, partial least squares regression (PLSR) and support vector regression (SVR) were employed to predict the sugar content and dry cell weight during fermentation. The best respective predictive R2 values for reducing sugar, tremella polysaccharide and dry cell weight were found to be 0.965, 0.988, and 0.970. Furthermore, due to its ability to capture nonlinear data relationships, SVR had superior performance in prediction modeling than PLSR. The results demonstrated that the combination of electronic sensor fusion signals and chemometrics provided a promising method for effectively monitoring T. fuciformis fermentation.


Assuntos
Basidiomycota , Colorimetria , Nariz Eletrônico , Fermentação , Basidiomycota/metabolismo , Colorimetria/métodos , Quimiometria/métodos , Análise de Componente Principal , Análise dos Mínimos Quadrados
10.
Biosensors (Basel) ; 14(2)2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38391989

RESUMO

This paper presents a cost-effective, quantitative, point-of-care solution for urinalysis screening, specifically targeting nitrite, protein, creatinine, and pH in urine samples. Detecting nitrite is crucial for the early identification of urinary tract infections (UTIs), while regularly measuring urinary protein-to-creatinine (UPC) ratios aids in managing kidney health. To address these needs, we developed a portable, transmission-based colorimeter using readily available components, controllable via a smartphone application through Bluetooth. Multiple colorimetric detection strategies for each analyte were identified and tested for sensitivity, specificity, and stability in a salt buffer, artificial urine, and human urine. The colorimeter successfully detected all analytes within their clinically relevant ranges: nitrite (6.25-200 µM), protein (2-1024 mg/dL), creatinine (2-1024 mg/dL), and pH (5.0-8.0). The introduction of quantitative protein and creatinine detection, and a calculated urinary protein-to-creatinine (UPC) ratio at the point-of-care, represents a significant advancement, allowing patients with proteinuria to monitor their condition without frequent lab visits. Furthermore, the colorimeter provides versatile data storage options, facilitating local storage on mobile devices or in the cloud. The paper further details the setup of the colorimeter's secure connection to a cloud-based environment, and the visualization of time-series analyte measurements in a web-based dashboard.


Assuntos
Nitritos , Urinálise , Humanos , Creatinina/urina , Proteinúria/diagnóstico , Proteinúria/urina , Concentração de Íons de Hidrogênio
11.
Genes (Basel) ; 14(12)2023 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-38137056

RESUMO

Color can be an indicator of plant health, quality, and productivity, and is useful to researchers to understand plant nutritional content in their studies. Color may be related to chlorophyll content and photosynthetic activity and provides information for those studying diseases and mineral nutrition because every nutrient deficiency and many diseases produce symptoms that affect color. In order to identify significant loci related to both leaf and pod color in a snap bean (Phaseolus vulgaris L.) diversity panel, a genome-wide association study (GWAS) was carried out. Leaf color in one and pod traits in multiple environments were characterized using a colorimeter. L*a*b* color data were recorded and used to calculate chroma (C*) and hue angle (H°). Leaves were evaluated at three positions (lower, middle, and upper) in the canopy and both pod exterior and interior colors were obtained. GWAS was conducted using two reference genomes that represent the Andean (G19833) and Middle American (5-593) domestication centers. Narrow sense heritabilities were calculated using the mixed linear model (MLM) method in genome association and prediction integrated tool (GAPIT), and significant single nucleotide polymorphisms (SNPs) for each color parameter were obtained using the Bayesian-information and linkage-disequilibrium iteratively nested keyway (BLINK) GWAS model with two principal components (PCAs). In comparison to pod color traits, narrow sense heritabilities of leaf traits were low and similar for both reference genomes. Generally, narrow sense heritability for all traits was highest in the lower, followed by middle, and then upper leaf positions. Heritability for both pod interior and exterior color traits was higher using the G19833 reference genome compared to 5-593 when evaluated by year and means across years. Forty-five significant SNPs associated with leaf traits and 872 associated with pods, totaling 917 significant SNPs were identified. Only one SNP was found in common for both leaf and pod traits on Pv03 in the 5-593 reference genome. One-hundred thirteen significant SNPs, 30 in leaves and 83 in pods had phenotypic variation explained (PVE) of 10% or greater. Fourteen SNPs (four from G19833 and ten from 5-593) with ≥10 PVE%, large SNP effect, and largest p-value for L* and H° pod exterior was identified on Pv01, Pv02, Pv03, and Pv08. More SNPs were associated with pod traits than with leaf traits. The pod interior did not exhibit colors produced by anthocyanins or flavonols which allowed the differentiation of potential candidate genes associated with chloroplast and photosynthetic activity compared to the pod exterior where candidate genes related to both flavonoids and photosynthesis affected color. Several SNPs were associated with known qualitative genes including the wax pod locus (y), persistent color (pc), purple pods (V), and two genes expressed in seeds but not previously reported to affect other plant tissues (B and J). An evaluation of significant SNPs within annotated genes found a number, within a 200 kb window, involved in both flavonoid and photosynthetic biosynthetic pathways.


Assuntos
Estudo de Associação Genômica Ampla , Phaseolus , Estados Unidos , Antocianinas , Teorema de Bayes , Phaseolus/genética , Folhas de Planta/genética
12.
Leg Med (Tokyo) ; 69: 102343, 2023 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-37923590

RESUMO

Bloodstain age estimation is important in forensic science. Although several studies have used spectroscopy to estimate bloodstain ages, this method has not yet been practically applied due to the need for expensive equipment and low reproducibility. Thus, we aimed to develop a bloodstain age estimation model that can be easily performed using a spectrophotometric colorimeter. First, bloodstains were prepared by placing blood obtained from five healthy volunteers on a plastic plate. The bloodstains were kept on conditions with various brightness and temperatures. Then, each bloodstain was dissolved in saline every 24 h to a final concentration of 1%, measured with a spectrophotometric colorimeter, and subjected to machine learning to generate a random forest regression (RFR) model, and finally, the prediction accuracy of the bloodstain age was verified. We also elucidated the mechanism of the color changes utilizing aminoguanidine, which is an inhibitor of Maillard reaction. Finally, we measured the time-dependent color changes of the blood fluids obtained from healthy volunteers and examined if the method could be potentially applied to estimate postmortem interval (PMI). Our results showed that the RFR model estimated the bloodstain age with no substantial assessment, and it was applicable to bloodstains, regardless of the brightness or temperature. The color changes were affected by the addition of aminoguanidine. Furthermore, the method could be applied to blood fluids, suggesting its potential usefulness for PMI estimation. Considering its feasibility, the present method could potentially be introduced to practical forensic sciences in the near future.

13.
Poult Sci ; 102(11): 103052, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37734360

RESUMO

The BG line, originated by crossing 2 Chinese indigenous breeds, Dongxiang blue eggshell and Jiangshan black-bone, has been bred for black carcass and blue-greenish eggs. Aiming to study the genetic parameters and selection aspects of these eggshell colors, the 4 colorimeter parameters (L*, a*, b*, SCI = L*-a*-b*) were measured on ∼5 eggs/hen/age (200 d and 300 d) from each hen in 3 generations (G4 = 452, G5 = 508, G6 = 498). Visual eggshell color was classified as either "Light," "Blue," "Green," or "Olive," and data from G4 and G5 indicated that visual eggshell color was more accurately determined by combining the classifications of single representative egg/hen by 4 independent observers. Based on the apparent gradual variation in visual color, the 4 colors were expressed numerically (Light = 1, Blue = 2, Green = 3, Olive = 4) and the averages of the 4 observers (AveObs) were used as quantitative expression of the visual color of each egg. This expression, in the range from Blue to Olive, was highly significantly correlated with L*, b* and SCI. The a* values were also associated with AveObs, but not linearly; AveObs between 2 (Blue) and 3 (Green) had lowest a*, and it increased as AveObs was more Light (<2) or more Olive (>3). The heritability estimates of the colorimeter parameters were mostly very high; those of b* and SCI ranged between 0.7 and 0.8, and those of L* and a* between 0.6 and 0.7, indicating that they can serve as criterions to select for blue and/or green eggshells. The phenotypic and genetic correlations between the colorimeter parameters were highly significant and favorable. It is suggested that effective breeding for blue eggs can be done by selecting hens laying eggs with highest SCI/L* or lowest b* (against green and olive shades), followed by selection for low a* (against light shades). Breeding for green eggs can be done by selecting hens laying eggs with SCI ≈ 75 and/or L* ≈ 80 and/or b* ≈ 12. Breeding for hens that lay either blue or green eggs can be done by selection for low a* values.

14.
Spectrochim Acta A Mol Biomol Spectrosc ; 302: 123009, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37330334

RESUMO

Novel spectrophotometric and smartphone-based colorimetric methods were developed and validated for the estimation of atenolol (ATE) in pharmaceutical formulations. The measurement procedure is based on the de-diazotization reaction, in which ATE is able to inhibit the diazotized sulfanilic acid from reacting with 8-hydroxy quinoline (8-HQ) in a basic medium. As a result, the formation of red-orange color azo-dye is hindered, and the color intensity is decreased proportionally to concentration of ATE. In spectrophotometric method the azo-dye color fate was monitored at 495 nm. While in smartphone-based colorimetric (SBC) method the captured image in the design processed by RGB App and transferred to the absorbance. The reactant concentrations were optimized using a central composite design (CCD) and response surface method. The methods exhibit good linearity in the 8.0 to 60.0 µg mL-1 range with no significant effect of interferences. The spectrophotometric method yields a linear equation with a slope of 0.0187 (R2 = 0.9993), a limit of detection (LOD) of 1.28 µg mL-1, and a limit of quantification (LOQ) of 4.28 µg mL-1. On the other hand, the smartphone-based colorimetric (SBC) method demonstrates a linear equation with a slope of 0.0127 (R2 = 0.9965), an LOD of 2.13 µg mL-1, and an LOQ of 7.09 µg mL-1. Analyzing ATE in pharmaceutical tablets was utilized to validate the applicability of the developed methods, and the results were statistically compared with those obtained by the HPLC method using the t-test and F-test.


Assuntos
Atenolol , Colorimetria , Colorimetria/métodos , Composição de Medicamentos , Smartphone , Comprimidos
15.
Artigo em Inglês | MEDLINE | ID: mdl-37317735

RESUMO

Background Sturge-Weber syndrome (SWS) is a rare condition associated with a GNAQ gene mutation, which affects neural crest cells. A pulsed dye laser (PDL) is a first-line therapy for SWS, but its outcomes are worse than those in patients with port-wine stains (PWS). Photodynamic therapy (PDT) is a promising therapeutic option for PWS. However, its use for PWS associated with SWS has rarely been studied. Aims To investigate the therapeutic and adverse effects of photodynamic therapy in treating SWS-associated PWS. Methods Patients with SWS and matched patients with large size facial PWS were included in this study. Both colorimetric assessment and visual evaluation were conducted to evaluate patients' responses to treatment. Results Colorimetric assessment (blanching rate) and visual evaluation (scores of colour improvement) showed that after two PDT treatments, the SWS and PWS groups had similar treatment responses (21.2% vs. 29.8%; 3.39 vs. 3.65; P = 0.18, P = 0.37). However, there was a significant difference in efficacy between patients with SWS with and without a treatment history (12.4 and 34.9%, respectively; P = 0.02), as well as between patients with lesions located on the central and lateral faces (18.5 and 36.8%, respectively; P = 0.01). Both the SWS and PWS groups experienced minor adverse effects, and the frequency of these effects was not significantly different between the two groups. Limitation The study was limited by a small sample size and the possibility of later onset of glaucoma. In addition, false-negative magnetic resonance imaging screening results for SWS could not be ruled out due to the young age of some participants. Conclusion Photodynamic therapy is a safe and effective therapeutic option for SWS-associated PWS. Patients without a treatment history, and lesions on the lateral face, responded well, demonstrating good efficacy.

16.
Anat Histol Embryol ; 51(4): 542-548, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35726566

RESUMO

The aim of the study is to protect and preserve the cross-sectional diagnostic characteristics of the anatomy samples by using silicone plastination method, to examine them both macroscopically and microscopically, and to use them as an educational material. After the dissection procedures of 10 total sheep heads obtained from the slaughterhouse were completed, they were freshly frozen and sliced to prepare cross-sectional samples. Then, statistical analysis was performed after the colorimetric measurements. For microscopic examination, 30 brain samples were divided into three groups (Fresh-F, plastination-P, plastination/deplastination-P/D). Of the total brain samples, 20 were subject to routine plastination protocol. After the plastination/deplastination procedure, the changes occurring in cerebral histology were compared. In terms of tissue preservation, the effect of plastination and deplastination was examined using a light microscope. Plastinates subject to silicone plastination under room temperature were very similar to their natural appearance, and it was observed that they preserved their morphological features. Colour changes in the tissues were statistically evaluated. Volumetric shrinkages were observed as qualitative, especially in the brain. As a result of the evaluation done, it was seen that deplastination with toluene is not possible for the brain tissues. In addition, it was not possible to take cross sections of the plastinated tissues that were not deplastinated. On the contrary, findings regarding that deplastination with 5% sodium methoxide dissolved in methanol can allow microscopic examination in long-term preserved plastinated brain tissues were obtained.


Assuntos
Plastinação , Animais , Encéfalo , Colorimetria/veterinária , Estudos Transversais , Plastinação/métodos , Plastinação/veterinária , Ovinos , Silicones
17.
Front Pharmacol ; 13: 599979, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35592420

RESUMO

In recent years, the domestic and international trade volumes of Chinese medicinal materials (CMMs) keep increasing. By the end of 2019, the total amount of exported CMMs reached as high as US $1.137 billion, while imported was US $2.155 billion. A stable and controllable quality system of CMMs apparently becomes the most important issue, which needs multifaceted collaboration from harvesting CMMs at a proper season to storing CMMs at a proper temperature. However, due to imperfect storage conditions, different kinds of deteriorations are prone to occur, for instance, get moldy or rancid, which not only causes a huge waste of CMM resources but also poses a great threat to clinical medication safety and public health. The key issue is to quickly and accurately distinguish deteriorated CMM samples so as to avoid consuming low-quality or even harmful CMMs. However, some attention has been paid to study the changing quality of deteriorated CMMs and a suitable method for identifying them. In this study, as a medicine and food material which easily becomes rancid, armeniacae semen amarum (ASA) was chosen as a research objective, and experimental ASA samples of different rancidness degrees were collected. Then, various kinds of analytical methods and technologies were applied to explore the changing rules of ASA quality and figure out the key indicators for the quality evaluation of ASA in the rancid process, including the human panel, colorimeter, electronic nose, and GC/MS. This study aims to analyze the correlation between the external morphological features and the inner chemical compounds, to find out the specific components from "quantitative change" to "qualitative change" in the process of "getting rancid," and to discover the dynamic changes in the aforementioned key indicators at different stages of rancidness. The results showed since ASA samples began to get rancid with the extension of storage time, morphological features, namely, surface color and smell, changed significantly, and the degree of rancidness further deepened at the same time. Based on macroscopic identification accomplished via the human panel, ASA samples with varying degrees of rancidness were divided into four groups. The result of colorimeter analysis was in agreement with that of the human panel, as well as the determination of the amygdalin content and peroxide value. Moreover, there were obvious differences in the amygdalin content and peroxide value among ASA samples with different rancidness degrees. With a higher degree of rancidness, the content of amygdalin decreased, while the peroxide value increased significantly. The rancidness degree of ASA has a negative correlation with the amygdalin content and a positive correlation with the peroxide value. The newly discovered nonanal and 2-bromopropiophenone in rancid ASA samples may be the key components of "rancidity smell," and these two components would be the exclusive components that trigger "quantitative change" to "qualitative change" in the process of rancidness of ASA. This study sheds light on studying the internal mechanism of "rancidness" of CMMs and provides an important basis for the effective storage and safe medication of easy-to-get rancid herbs, and it also plays an important foundation for the establishment of a stable and controllable quality system for CMMs.

18.
Biosensors (Basel) ; 12(4)2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35448308

RESUMO

In emergency medicine, the lactate level is commonly used as an indicator of the severity and response to the treatment of hypoperfusion-related diseases. Clinical lactate measurements generally require 3 h for clinical determination. To improve the current gold standard methods, the development of sensor devices that can reduce detection time while maintaining sensitivity and providing portability is gaining great attention. This study aimed to develop a polyaniline (PAni)-based single-sensor platform for sensing lactate in human sweat using a CIELAB color system-based colorimetric device. To establish a lactate sensing platform, PAni nanoparticles were synthesized and adsorbed on the filter paper surface using solvent shift and dip-coating methods, respectively. PAni is characterized by a chemical change accompanied by a color change according to the surrounding environment. To quantify the color change of PAni, a CIELAB color system-based colorimetric device was fabricated. The color change of PAni was measured according to the chemical state using a combination of a PAni-based filter paper sensor platform and a colorimetric device, based on the lactate concentration in deionized water. Finally, human sweat was spiked with lactate to measure the color change of the PAni-based filter paper sensor platform. Under these conditions, the combination of polyaniline-based sensor platforms and colorimetric systems has a limit of detection (LOD) and limit of quantitation (LOQ) of 1 mM, linearity of 0.9684, and stability of 14%. Tbe confirmed that the color of the substrate changes after about 30 s, and through this, the physical fatigue of the individual can be determined. In conclusion, it was confirmed through this study that a combination of the PAni paper sensor platform and colorimeter can detect clinically meaningful lactate concentration.


Assuntos
Nanopartículas , Suor , Compostos de Anilina , Colorimetria/métodos , Humanos , Ácido Láctico/análise , Suor/química
19.
Talanta ; 245: 123489, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35460981

RESUMO

On-site quantitative analysis of pesticides is important for food safety. Colorimetric gold nanobipyramids (AuNBPs) sensors are powerful methods for on-site detection. However, a single quantitative method and the instability of AuNBPs in solution limit the practicability of those sensors. Here, a paper-based multicolor AuNBPs sensor involved a colorimeter-assisted method for quantifying color was developed for quantitative detection of 2,4-dichlorophenoxyacetic acid (2,4-D), a common herbicide. The novelty of this study lies in developing a general paper-based quantitative on-site method (PQOM) for colorimetric AuNBPs sensors. Firstly, a paper-based analytical device (PAD) consisting of a nylon membrane, absorbent cotton layers, and two acrylic plates was fabricated to deposit AuNBPs. We demonstrated the PAD could improve the stability of AuNBPs and the detection sensitivity of AuNBPs sensors. Then, a handheld colorimeter was first used to quantify the color change of AuNBPs on the PAD based on the CIELab color space. Finally, as proof of concept, the PQOM was successfully employed to quantify 2,4-D by combining with an alkaline phosphatase-mediated AuNBPs growth method. In this method, 2,4-D specifically inhibited alkaline phosphatase activity to suppress the generation of l-ascorbic acid, thereby mediating AuNBPs growth. The developed sensor exhibited seven 2,4-D concentration-related colors and detected as low as 50 ng mL-1 2,4-D by naked-eye observation and 18 ng mL-1 2,4-D by a colorimeter. It was applied to detect 2,4-D in the spiked rice and apple samples with good recovery rates (91.8-112.0%) and a relative standard deviation (n = 5) < 5%. The success of this study provides a sensing platform for quantifying 2,4-D on site.


Assuntos
Ouro , Herbicidas , Ácido 2,4-Diclorofenoxiacético , Fosfatase Alcalina , Colorimetria/métodos , Corantes , Limite de Detecção
20.
Arch Microbiol ; 204(5): 282, 2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35471713

RESUMO

Magnetotactic bacteria (MTB) use iron from their habitat to create magnetosomes, a unique organelle required for magnetotaxis. Due to a lack of cost-effective assay methods for estimating iron in magnetosomes, research on MTB and iron-rich magnetosomes is limited. A systemized assay was established in this study to quantify iron in MTB using ferric citrate colorimetric estimation. With a statistically significant R2 value of 0.9935, the iron concentration range and wavelength for iron estimation were optimized using linear regression. This colorimetric approach and the inductively coupled plasma optical emission spectrometry (ICP-OES) exhibited an excellent correlation R2 value of 0.961 in the validatory correlative study of the iron concentration in the isolated magnetotactic bacterial strains. In large-scale screening studies, this less-expensive strategy could be advantageous.


Assuntos
Magnetossomos , Colorimetria , Óxido Ferroso-Férrico/análise , Bactérias Gram-Negativas , Ferro , Modelos Lineares , Magnetossomos/química
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