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1.
Pharmaceuticals (Basel) ; 17(7)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-39065722

RESUMO

Mefloquine (MQ) is an antimalarial medication prescribed to treat or malaria prevention.. When taken by children, vomiting usually occurs, and new doses of medication frequently need to be taken. So, developing pediatric medicines using taste-masked antimalarial drug complexes is mandatory for the success of mefloquine administration. The hypothesis that binding mefloquine to an ion-exchange resin (R) could circumvent the drug's bitter taste problem was proposed, and solid-state 13C cross-polarization magic angle spinning (CPMAS) NMR was able to follow MQ-R mixtures through chemical shift and relaxation measurements. The nature of MQ-R complex formation could then be determined. Impedimetric electronic tongue equipment also verified the resinate taste-masking efficiency in vitro. Variations in chemical shifts and structure dynamics measured by proton relaxation properties (e.g., T1ρH) were used as probes to follow the extension of mixing and specific interactions that would be present in MQ-R. A significant decrease in T1ρH values was observed for MQ carbons in MQ-R complexes, compared to the ones in MQ (from 100-200 ms in MQ to 20-50 ms in an MQ-R complex). The results evidenced that the cationic resin interacts strongly with mefloquine molecules in the formulation of a 1:1 ratio complex. Thus, 13C CPMAS NMR allowed the confirmation of the presence of a binding between mefloquine and polacrilin in the MQ-R formulation studied.

2.
Medicina (B.Aires) ; Medicina (B.Aires);84(supl.1): 37-42, mayo 2024.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1558482

RESUMO

Resumen El autismo es un trastorno del neurodesarrollo de base neurobiológica con alta prevalencia y claro predo mino en varones. Se caracteriza por déficits en la cog nición social y la comunicación, intereses restringidos y conductas estereotipadas, frecuentemente asociado a disfunciones sensoriales, otras condiciones del neuro desarrollo, trastornos neuropsiquiátricos, epilepsia y/o trastornos de sueño. Esta condición acompañará a las personas a lo largo de toda la vida, lo cual generará diversas necesidades de apoyo y tratamientos. Las personas con autismo muchas veces necesitan "encajar", para ello utilizan técnicas como el camuflaje, también denominada enmascara miento. Esta actitud se ha observado en personas con desarrollo típico y en personas con autismo en la infan cia, adolescencia y vida adulta, aunque en los autistas esta conducta es más intensa y lleva más tiempo, y se la identifica con más frecuencia e intensidad en mujeres adultas autistas. Esto podría explicar el subregistro de autismo, el diagnóstico más tardío, el retraso en el abordaje tera péutico y la mayor presencia de trastornos de ansiedad y depresión relacionados al esfuerzo que implica "pa recer normal". Si bien las personas al camuflar parecen ser "normales" y encajan perfectamente, ésta no es una actitud que debiera propiciarse, por el contrario es imperativo trabajar para mejorar el entorno y la com prensión de cada persona. En este trabajo analizamos los aspectos clínicos, su relación con la edad, sexo, y formas de detección del mismo.


Abstract Autism is a neurobiologically based neurodevelop mental disorder with high prevalence and a clear pre dominance in males. It is characterized by deficits in social cognition and communication, restricted inter ests, and stereotyped behaviors, frequently associated with sensory dysfunction others neurodevelopmental conditions, neuropsychiatric disorders, epilepsy, and/or sleep disorders. This condition will accompany people throughout their lives, which will generate various sup port and treatment needs. People with autism often need to "fit in" and for this they use techniques such as camouflage, also called masking. This attitude has been observed in people with typical development and in people with autism in childhood, adolescence and adult life, although in autistic people this behavior is more intense and takes longer and with more frequency and intensity in autistic adult women. This could explain the underreporting of autism, the later diagnosis, the delay in the therapeutic approach, and the greater presence of anxiety and depression disorders related to the effort that "appearing normal" implies. Even though camouflage people appear to be "normal" and fit in perfectly, this is not an attitude that we should promote and, on the contrary, it is imperative to work to improve the environment and the under standing of each person. In this paper we will analyze the clinical aspects, their relationship with age, sex, and ways of detecting it.

3.
Medicina (B Aires) ; 84 Suppl 1: 37-42, 2024 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-38350623

RESUMO

Autism is a neurobiologically based neurodevelopmental disorder with high prevalence and a clear predominance in males. It is characterized by deficits in social cognition and communication, restricted interests, and stereotyped behaviors, frequently associated with sensory dysfunction others neurodevelopmental conditions, neuropsychiatric disorders, epilepsy, and/or sleep disorders. This condition will accompany people throughout their lives, which will generate various support and treatment needs. People with autism often need to "fit in" and for this they use techniques such as camouflage, also called masking. This attitude has been observed in people with typical development and in people with autism in childhood, adolescence and adult life, although in autistic people this behavior is more intense and takes longer and with more frequency and intensity in autistic adult women. This could explain the underreporting of autism, the later diagnosis, the delay in the therapeutic approach, and the greater presence of anxiety and depression disorders related to the effort that "appearing normal" implies. Even though camouflage people appear to be "normal" and fit in perfectly, this is not an attitude that we should promote and, on the contrary, it is imperativeto work to improve the environment and the understanding of each person. In this paper we will analyze the clinical aspects, their relationship with age, sex, and ways of detecting it.


El autismo es un trastorno del neurodesarrollo de base neurobiológica con alta prevalencia y claro predomino en varones. Se caracteriza por déficits en la cognición social y la comunicación, intereses restringidos y conductas estereotipadas, frecuentemente asociado a disfunciones sensoriales, otras condiciones del neurodesarrollo, trastornos neuropsiquiátricos, epilepsia y/o trastornos de sueño. Esta condición acompañará a las personas a lo largo de toda la vida, lo cual generará diversas necesidades de apoyo y tratamientos. Las personas con autismo muchas veces necesitan "encajar", para ello utilizan técnicas como el camuflaje, también denominada enmascaramiento. Esta actitud se ha observado en personas con desarrollo típico y en personas con autismo en la infancia, adolescencia y vida adulta, aunque en los autistas esta conducta es más intensa y lleva más tiempo, y se la identifica con más frecuencia e intensidad en mujeres adultas autistas. Esto podría explicar el subregistro de autismo, el diagnóstico más tardío, el retraso en el abordaje terapéutico y la mayor presencia de trastornos de ansiedad y depresión relacionados al esfuerzo que implica "parecer normal". Si bien las personas al camuflar parecen ser "normales" y encajan perfectamente, ésta no es una actitud que debiera propiciarse, por el contrario es imperativo trabajar para mejorar el entorno y la comprensión de cada persona. En este trabajo analizamos los aspectos clínicos, su relación con la edad, sexo, y formas de detección del mismo.


Assuntos
Transtorno Autístico , Masculino , Adulto , Adolescente , Humanos , Feminino , Transtorno Autístico/psicologia , Comportamento Estereotipado , Comunicação , Transtornos de Ansiedade , Ansiedade
4.
J Esthet Restor Dent ; 36(5): 761-769, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38010079

RESUMO

OBJECTIVE: Demonstrate the ability of 0.5 mm thickness lithium disilicate laminates associated with resin cement to mask different substrate saturations. METHODS: 60 specimens (n = 5) were prepared with CAD/CAM lithium disilicate glass-ceramic IPS e.max CAD, 0.5 mm thick, in three degrees of translucency (HT, MT and LT); cemented by Variolink Esthetic LC Light+ (L) and Neutral (N) on composite resin substrates A1 and A4 shades. Color measurements were performed by a spectrophotometer (CM-3700d -Konica Minolta). The L*, a*, b* parameters of the tri-layer structure (laminate/ resin cement/ substrate) were used to calculate color difference ( ∆ E 00 ) by CIEDE2000 formula and Translucency Parameter ( TP 00 ). This study adopted ∆ E 00 = 0.8, as perceptibility threshold (PT), and ∆ E 00 = 1.8, as acceptability threshold (AT). Statistical analyses were performed by one-way ANOVA and Tukey tests (a = 0.05). RESULTS: Color difference between resin cement shades showed statistical differences (p < 0.0001) and ∆ E 00 > 1.8 for all groups. Color difference between substrates saturations showed a significant statistical difference (p < 0.0001) and ∆ E 00 values above AT for all groups. The TP 00 demonstrated significant statistical differences (p < 0.0001). The LTL combination, the opaquest set, showed the smallest ∆ E 00 values between substrate shades differences, however, above AT. CONCLUSION: The translucency of the lithium disilicate, the substrate saturation and the resin cement opacity influenced final color of restoration. The ceramic translucency impact on final color was reduced by opaque resin cement. Furthermore, the LT lithium disilicate and the Light+ resin cement reduced the translucency of the restoration, contributing to mask saturated substrate. CLINICAL RELEVANCE: This study shows the influence of conservative lithium disilicate laminates with different degrees of translucency associated with resin cement on final color of saturated substrate restorations. A minimally invasive esthetic protocol for masking substrates is demonstrated by associating low translucency ceramic laminates and opaque resin cement.


Assuntos
Estética Dentária , Cimentos de Resina , Cimentos de Resina/química , Porcelana Dentária/química , Cerâmica/química , Teste de Materiais , Cor , Propriedades de Superfície
5.
Distúrb. comun ; 35(1): e57675, 01/06/2023.
Artigo em Português | LILACS | ID: biblio-1436211

RESUMO

Introdução: O zumbido é uma ilusão auditiva consciente, uma sensação sonora não relacionada com uma fonte externa de estimulação. Objetivos: Caracterizar a Acufenometria, Limiar Diferencial de Mascaramento, o questionário de qualidade de vida Inventário de Desvantagem do Zumbido e Potencial Auditivo de Tronco Encefálico em adultos normo-ouvintes com zumbido, com a finalidade de comparar seus achados. Método: Vinte indivíduos do sexo feminino e masculino, entre 20 e 60 anos de idade, normo-ouvintes com queixa de zumbido, foram submetidos ao Acufenometria, Limiar Diferencial de Mascaramento, Inventário de Desvantagem do Zumbido e Potencial Evocado Auditivo de Tronco Encefálico. Resultados: AAcufenometriarevelou que o pitch médio foi de 4,3 KHz à orelha direita e 4,6 KHz à orelha esquerda. O loudness médio foi de 21,7 dBNS à orelha direita e 23,5 dBNS à orelha esquerda. O Limiar Diferencial de Mascaramento médio mostrou-se alterado. O Inventário de Desvantagem do Zumbido médio correspondeu à classificação de grau leve. O Potencial Evocado Auditivo de Tronco Encefálico apresentou parâmetros dentro da normalidade bilateralmente. Conclusão: Constatou-se que adultos normo-ouvintes com queixa de zumbido apresentam zumbido de pitch agudo bilateral com discreto impacto na qualidade de vida, condução adequada das vias auditivas até o tronco encefálico e comprometimento na identificação de sons na presença de ruído, demonstrando que o zumbido pode ter repercussões nas habilidades auditivas centrais. (AU)


Introduction: Tinnitus is a conscious auditory illusion, a sound perception unrelated to any external stimulus source. Objectives: To characterize the Acuphenometry, Masking Level Difference, the quality of life questionnaire Tinnitus Handicap Inventory and Auditory Brainstem Response in normal hearing adults with tinnitus, with the purpose of comparing the findings. Method: Twenty female and male individuals, between 20 and 60 years of age, normal hearing with complaints of tinnitus, underwent Acuphenometry, Masking Level Difference, Tinnitus Handicap Inventory and Auditory Brainstem Response. Results: The Acuphenometry showed the average pitch was 4.3 KHz to the right ear and 4.6 KHz to the left ear. The average loudness was 21.7 dBSL to the right ear and 23.5 dBs to the left ear. The average Masking Level Difference was altered. The average Tinnitus Handicap Inventory corresponded to the classification of mild grade. Auditory Brainstem Response showed parameters within normal range bilaterally. Conclusion: It was found that normal hearing adults with tinnitus complaints have bilateral acute pitch tinnitus with a slight impact on quality of life, appropriate conduction of auditory pathways to the brainstem and impaired identification of sounds in the presence of noise, demonstrating that tinnitus can have repercussions on central auditory skills. (AU)


Introducción: El tinnitus es una ilusión auditiva consciente, una sensación de sonido no relacionada con una fuente externa de estimulación. Objetivos: Caracterizar la coincidencia de tono y volumen, el umbral de enmascaramiento diferencial, el inventario de minusvalía para acúfenos y el potencial auditivo del tronco encefálico en adultos normoyentes con acúfenos, con el fin de comparar sus hallazgos. Método:Veinte sujetos masculinos y femeninos, con edades entre 20 y 60 años, audición normal con tinnitus, fueron sometidos a acúfenos, Umbral de Enmascaramiento Diferencial, Inventario de Desventajas de Tinnitus y Potenciales Evocados Auditivos del Tronco Encefalico. Resultados: La combinación de tono y volumen reveló que el tono promedio era de 4,3 KHz en el oído derecho y de 4,6 KHz en el oído izquierdo. Mientras que el volumen medio fue de 21,7 dBNS para el oído derecho y de 23,5 dBNS para el oído izquierdo. Se modificó el umbral diferencial de enmascaramiento promedio. El Inventario de Desventajas de Tinnitus promedio correspondió a la clasificación de grado leve. El Potenciales Evocados Auditivos del Tronco Encefalico presentó parámetros dentro del rango normal bilateralmente. Conclusión:Se encontró que los adultos normooyentes con quejas de tinnitus presentan tinnitus de tono alto bilateral con leve impacto en la calidad de vida, conducción adecuada de las vías auditivas al tronco encefálico y deterioro en la identificación de sonidos en presencia de ruido, demostrando que Tinnitus puede tener repercusiones en las habilidades auditivas centrales. (AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Zumbido/etiologia , Testes Auditivos , Mascaramento Perceptivo , Limiar Auditivo , Inquéritos e Questionários , Potenciais Evocados Auditivos do Tronco Encefálico
6.
Front Neurosci ; 17: 1151776, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37139520

RESUMO

Among the many questions regarding the ability to effortlessly name musical notes without a reference, also known as absolute pitch, the neural processes by which this phenomenon operates are still a matter of debate. Although a perceptual subprocess is currently accepted by the literature, the participation of some aspects of auditory processing still needs to be determined. We conducted two experiments to investigate the relationship between absolute pitch and two aspects of auditory temporal processing, namely temporal resolution and backward masking. In the first experiment, musicians were organized into two groups according to the presence of absolute pitch, as determined by a pitch identification test, and compared regarding their performance in the Gaps-in-Noise test, a gap detection task for assessing temporal resolution. Despite the lack of statistically significant difference between the groups, the Gaps-in-Noise test measures were significant predictors of the measures for pitch naming precision, even after controlling for possible confounding variables. In the second experiment, another two groups of musicians with and without absolute pitch were submitted to the backward masking test, with no difference between the groups and no correlation between backward masking and absolute pitch measures. The results from both experiments suggest that only part of temporal processing is involved in absolute pitch, indicating that not all aspects of auditory perception are related to the perceptual subprocess. Possible explanations for these findings include the notable overlap of brain areas involved in both temporal resolution and absolute pitch, which is not present in the case of backward masking, and the relevance of temporal resolution to analyze the temporal fine structure of sound in pitch perception.

7.
J Esthet Restor Dent ; 35(2): 333-344, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36260930

RESUMO

OBJECTIVE: To map the existing evidence regarding the masking ability of resin composites. OVERVIEW: The literature search was conducted electronically, based on the PRISMA Extension for Scoping Reviews-online protocol at https://osf.io/m2h67/ with no language or time restrictions. Two independent reviewers conducted the screening, and a third reviewer was consulted in case of disagreement. Studies that evaluated resin composite masking ability regardless of background, application technique, thickness, or number of layers were selected. The search found 2995 potentially eligible studies. After removal of duplicates (657), irrelevant articles (2323), 15 citations met the eligibility criteria based on title and abstract, and eight studies were included based on full text analysis (seven in vitro, and one case report). Acceptable masking ability is obtained by one layer of opaque shade resin composite or by the layering technique. A black background is masked with 1.0- to 2.0 mm-thick layers of opaque shade resin composites. Masking of the C4 background is achieved with one layer of 0.5- to 1.5 mm-thick opaque shade resin composite or by the layering technique using different combinations of enamel body and dentin shades with a final thickness of 1.5 mm. CONCLUSIONS: Acceptable masking of C4 shade background is achieved with one layer of opaque shade composite at least 0.5 mm-thick or by different combinations of the layering technique, with a final thickness of 1.5 mm. Acceptable masking of the black background of the oral cavity is achieved with a resin composite of at least 1.0 mm opaque shade. CLINICAL SIGNIFICANCE: The thickness of the resin composite layer required to achieve adequate masking is variable and depends on the translucency/opacity of the tested resin composites and the background shade.


Assuntos
Colorimetria , Resinas Compostas , Humanos , Cor , Esmalte Dentário , Teste de Materiais
8.
CoDAS ; 35(1): e20200334, 2023. tab, graf
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1421277

RESUMO

RESUMO Objetivo analisar o efeito do mascaramento estável e modulado no Potencial Evocado Auditivo Cortical com estímulo de fala em adultos-jovens. Método participaram 14 indivíduos com idades entre 19 e 28 anos de ambos os sexos e sem perda auditiva. O exame de Potencial Evocado Auditivo Cortical foi realizado com estímulo de fala sintética /ba/ simultâneo ao ruído Speech Shaped Noise apresentado em três condições: ruído estável com intensidade de 30 dB NPSpe (ruído estável fraco), ruído estável com intensidade de 65 dB NPSpe (ruído estável forte) e ruído modulado em intensidade de 30 dB NPSpe e 65 dB NPSpe em 25Hz e com período de modulação de 40 ms. Resultados foram observadas maiores latências nos componentes corticais, exceto P2, na condição de ruído estável forte e medidas mais robustas de amplitude dos componentes corticais P1, N1 e P2 na condição de ruído modulado com diferença estatística significativa na comparação com a condição de ruído estável forte. Houve pior morfologia na condição de ruído estável forte, quando comparado aos demais registros. Os limiares eletrofisiológicos médios para as condições de ruído estável forte e ruído modulado foram 60 dB NPSpe e 49 dB NPSpe, respectivamente, mostrando 11,7 dB de diferença média. Conclusão podemos inferir que houve um menor efeito mascarante do ruído modulado, comparado à condição de ruído estável forte, nas medidas de amplitude dos componentes corticais e uma diferença média de 11,7 dB entre os limiares eletrofisiológicos (interpretado como a medida do Benefício do Mascaramento Modulado).


ABSTRACT Purpose To analyze the effect of masking on the Cortical Auditory Evoked Potential with speech stimulus in young adults. Methods Fourteen individuals aged between 19 and 28 years of both sexes with no hearing loss participated in the study. The Cortical Auditory Evoked Potential examination was performed with synthetic speech stimulus /ba/ simultaneous to Speech Shaped Noise presented under three conditions: steady noise with a 30 dB SPLep intensity (weak steady noise), steady noise with a 65 dB SPLep intensity o (strong steady noise) and modulated noise with 30 dB SPLep and 65 dB SPLep intensities at 25Hz and modulation period of 40 ms. Results Higher latencies were observed in the cortical components, except P2, in the condition of strong steady noise and more meaningful measures of amplitude of the cortical components P1, N1 and P2 in the condition of modulated noise with statistically significant difference in comparison to the strong steady noise condition. There was worse wave morphology in the condition of strong steady noise, when compared to the other records. The average electrophysiological thresholds for the conditions of strong steady noise and modulated noise were 60 dB SPLep and 49 dB SPLep, respectively, showing a 11.7 dB mean difference. Conclusion We could infer that there was a lower masking effect of modulated noise when compared to the strong steady noise condition, in the amplitude measurements of the cortical components and an average difference of 11.7 dB between the electrophysiological thresholds (interpreted as the measure of the Masking Release).

9.
Vis Neurosci ; 39: E006, 2022 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-36226362

RESUMO

Aging causes impairment of contrast sensitivity and chromatic discrimination, leading to changes in the perceptual interactions between color and luminance information. We aimed to investigate the influence of chromatic noise on luminance contrast thresholds in young and older adults. Forty participants were divided equally into Young (29.6 ± 6.3-year-old) and Elderly Groups (57.8 ± 6.6-year-old). They performed a luminance contrast discrimination task in the presence of chromatic noise maskers using a mosaic stimulus in a mosaic background. Four chromatic noise masking protocols were applied (protan, deutan, tritan, and no-noise protocols). We found that luminance contrast thresholds were significantly elevated by the addition of chromatic noise in both age groups (P < 0.05). In the Elderly group, but not the younger group, thresholds obtained in the tritan protocol were lower than those obtained from protan and deutan protocols (P < 0.05). For all protocols, the luminance contrast thresholds of elderly participants were higher than in young people (P < 0.01). Tritan chromatic noise was less effective in inhibiting luminance discrimination in elderly participants.


Assuntos
Percepção de Cores , Sensibilidades de Contraste , Adolescente , Adulto , Idoso , Humanos , Pessoa de Meia-Idade , Ruído , Estimulação Luminosa/métodos , Limiar Sensorial , Visão Ocular , Adulto Jovem
10.
J Clin Med ; 11(17)2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-36078863

RESUMO

There are still no valid, clinically feasible instruments to assess backward masking (BM), an auditory temporal processing (ATP) phenomenon. The aim of this study was to develop, standardize and present evidence of validity for a behavioral test for BM assessment. Young adults were submitted to a BM test (BMT), where they were asked to identify a 1000 Hz pure tone followed by a narrowband noise with interstimulus intervals of 0 to 400 ms and signal-to-noise ratio (SNR) between -20 and -30 dB. The correct response rate and target sound detection threshold were calculated, and the results compared with those of young adults with abnormal ATP tests and older adults. Diagnostic accuracy analyses were carried out. Young adults with normal ATP obtained an average correct response rate of 89 and 87% for SNR -20 and -30 dB, respectively, with average thresholds between 10 and 15 ms and no difference between the left and right ears. Results were more consistent at SNR -20 dB, and the best diagnostic accuracy was obtained for SNR -20 dB, with good specificity, but low sensitivity. Normative values were obtained for the BMT, which proved to be clinically feasible, with preliminary evidence of validity.

11.
J Clin Med ; 11(18)2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36142927

RESUMO

The Masking Level Difference (MLD) test is one of the main instruments for investigating binaural interaction. Studies with children aged 7-12 years still disagree about the influence of age on test performance and present discordant reference values. This study aimed to verify the effect of age on the performance of children aged 7-12 years in the MLD test and to establish reference values and cutoff criteria for this age group. Fifty-nine children with normal hearing were organized in three groups according to their age: 7-8 (n = 20), 9-10 (n = 20), and 11-12 (n = 19) years. The participants completed the MLD test by Auditec®. The Kruskal-Wallis statistical test was used to compare groups. Reference values were obtained by calculating mean, standard deviation, median, mode, and percentiles, while the cutoff criterion was obtained by subtracting two standard deviations from the mean. No statistically significant differences were observed between the groups regarding the MLD test measures. The mean MLD was 10.51 ± 1.84 dB and the cutoff point was set at 7 dB. Thus, reference values for the MLD test were established for children aged 7-12 years, who presented no effect of age on test performance.

12.
J Esthet Restor Dent ; 34(8): 1206-1212, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35851989

RESUMO

OBJECTIVE: To evaluate the effect of layering strategy and substrate color on the masking ability of resin composites. MATERIALS AND METHODS: A1-shaded specimens from Charisma Diamond and Filtek Z350XT were produced using different layering strategies. Color measurements were made by a reflectance spectrophotometer over A2, C2, A3.5, C3, C4 substrates. Color differences were calculated and interpreted by the 50%:50% perceptibility and acceptability visual thresholds. Data was analyzed by Kruskal-Wallis and Dunn post hoc test. Chi-square test was used to determine the association between masking ability, and independent variables. RESULTS: Color differences were significantly lower on A2 and C2 in comparison with C4 for the majority of the layering strategies. Acceptable matches were observed on most of the combinations over A2. Moderately unacceptable mismatches were observed in most of the combinations over C2 and A3.5. Clearly unacceptable mismatches were observed on the C3 and C4. The ΔE00 color shifts were predominantly influenced by ΔL00 for all layering strategies and substrate colors. CONCLUSION: Masking ability was affected by the layering strategy and substrate color. Acceptable masking was associated with A2 and C2, and with layering strategy composed of 0.5 mm enamel opacity and 1.0 mm dentin opacity thicknesses, using the Filtek Z350XT. CLINICAL SIGNIFICANCE: Resin composites-shade A1-applied by different layering strategies with a final thickness of 1.5 mm were able to mask mild and moderately discolored substrates. Severely discolored substrates were not masked effectively.


Assuntos
Resinas Compostas , Cor , Teste de Materiais , Espectrofotometria
13.
AAPS PharmSciTech ; 23(2): 69, 2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35112208

RESUMO

In this study, chloroquine resinates were prepared at a 1:1 (w:w) drug-to-resin ratio using the batch method with polacrilex (PC), sodium polystyrene sulfonate (SPS), and polacrilin potassium (PP) ion exchange resins (IER). The influence of drug/resin ratio and pH of the medium on drug loading efficiency was explored. UV-VIS spectrophotometric analysis showed that SPS resin had high loading efficiency for chloroquine diphosphate (CLP), above 89%, regardless of the pH. PP resin was more effective at pH 5.0 (90.68%) than at pH 1.0 (2.09%), and PC resin had only 27.63% of CLP loading efficiency. CLP complexation with IER yielded amorphous mixtures according to results from differential scanning calorimetry (DSC) and X-ray powder diffraction (XRPD), thus indicating drug-resin interaction. The taste masking efficiency was evaluated with in vitro methods using an adapted dissolution test and an electronic tongue system. During dissolution tests, SPS released only 1.0% of CLP after 300 s, while PP released over 10% after 90 s in simulated saliva solution. The electronic tongue distinguished the samples containing CLP, resins, and resinates by using multidimensional projection techniques that indicated an effective drug taste masking. In an accelerated stability study, the drug contents did not decrease in chloroquine resinates, and there was no physical degradation of the resinates after 60 days. Using chloroquine resinates therefore represents a novel way to evaluate taste masking in vitro which is relevant for the early formulation development process.


Assuntos
Resinas de Troca Iônica , Paladar , Administração Oral , Criança , Cloroquina , Estudos de Viabilidade , Humanos
14.
Front Immunol ; 12: 760817, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34950138

RESUMO

Monoclonal antibodies (mAbs) have been a valuable tool to elucidate several biological processes, such as stem cell differentiation and cancer, and contributed to virtually all areas of biomedical sciences. Yet, it remains a challenge to obtain mAbs specific to poorly expressed epitopes, or to epitopes that are actually involved in important biological phenomena, such as cell differentiation and metastasis. Drug-induced subtractive immunization, and recently the multiple tolerization subtractive immunization (MTSI) technique, reported by our group, have the potential to level up the field, as they direct the host´s immune response towards these epitopes. However, due to cyclophosphamide (CY) treatment, high mice mortality can be observed, and only a few data are available on how these techniques affect the immune system of mice. Tolerogen and immunogen cells, RWPE-1 and PC-3 cells, respectively, were individually seeded at 2 × 104 cells/cm2, and then adjusted to 2 × 106 cells per mouse before immunization, which was conducted in a subtractive approach (MTSI) with CY. Immunosuppression of mice was recorded via total white blood counting, as well the reactivity of circulating polyclonal antibodies (pAbs). General parameters, including weight, physical appearance, and behavior on mice subjected to three different concentrations of CY were recorded. mAbs were obtained using classical hybridoma techniques, using the spleen of immunized mice. After purification, antibodies were characterized by Western blotting, and Indirect immunofluorescence. In conclusion, all CY dosage were efficient in creating an immunosuppression state, but only the 100 mg/kg body weight was feasible, as the others resulted in extensive mice mortality. pAbs obtained in the peripheral blood of mice showed more reactivity towards tumor cells. MAbs 2-7A50 and 2-5C11 recognized antigens from tumor cells, but not from their non-tumor counterparts, as shown in western blotting and immunofluorescence assays. MTSI technique was successful in generating mAbs that recognize tumor-specific antigens.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Ciclofosfamida/administração & dosagem , Terapia de Imunossupressão/métodos , Imunossupressores/administração & dosagem , Animais , Especificidade de Anticorpos , Linhagem Celular , Epitopos/imunologia , Humanos , Contagem de Leucócitos , Masculino , Camundongos Endogâmicos BALB C
15.
Sensors (Basel) ; 21(15)2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34372248

RESUMO

Beamforming is a type of audio array processing techniques used for interference reduction, sound source localization, and as pre-processing stage for audio event classification and speaker identification. The auditory scene analysis community can benefit from a systemic evaluation and comparison between different beamforming techniques. In this paper, five popular beamforming techniques are evaluated in two different acoustic environments, while varying the number of microphones, the number of interferences, and the direction-of-arrival error, by using the Acoustic Interactions for Robot Audition (AIRA) corpus and a common software framework. Additionally, a highly efficient phase-based frequency masking beamformer is also evaluated, which is shown to outperform all five techniques. Both the evaluation corpus and the beamforming implementations are freely available and provided for experiment repeatability and transparency. Raw results are also provided as a complement to this work to the reader, to facilitate an informed decision of which technique to use. Finally, the insights and tendencies observed from the evaluation results are presented.


Assuntos
Acústica , Localização de Som , Percepção Auditiva , Humanos
16.
J Esthet Restor Dent ; 33(8): 1118-1131, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34085377

RESUMO

OBJECTIVE: To conduct a systematic review on the masking ability of discolored substrates, analyzing the capacity and quality of the response produced by the different methodologies and techniques applied to overcome this clinical challenge. MATERIALS AND METHODS: The study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The electronic search was conducted in MEDLINE/PubMed, Scopus and Web of Science databases, without date restriction. In vitro studies, written in English, applying different methodologies to evaluate masking ability were included. The variables of interest were: type, color and thickness of the restorative and/or cement material; use of pigments in the restorative material and/or cement; color of the substrate; and background color used for the evaluations. RESULTS: Database search retrieved 307 eligible papers with a final inclusion of 47 published papers. Approximately 98% of the studies used ΔE, 36% used TP, and only 6% used CR to evaluate the masking ability of restorative materials. CONCLUSIONS: The most appropriate methodology to evaluate the masking ability is using color difference equations (ΔE) associated with the perceptibility and acceptability thresholds. CLINICAL SIGNIFICANCE: As different methodologies have been used to evaluate the masking ability of esthetic restorative materials on colored substrates, there is an urgent need to reach a consensus and propose a method, which is suggested by the present systematic review.


Assuntos
Cerâmica , Porcelana Dentária , Cor , Materiais Dentários , Teste de Materiais
17.
Int J Audiol ; 60(12): 1016-1022, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33856947

RESUMO

OBJECTIVES: The aims of this study were to investigate auditory habits and binaural interaction among pilot and non-pilot military personnel from the Brazilian Air Force. DESIGN: A cross-sectional study using (1) an auditory habits questionnaire to outline the groups auditory profile and (2) the masking level difference test (MLD, Auditec, Saint Louis®) to evaluate and compare the groups. STUDY SAMPLE: Forty military male personnel aged between 30-40 years old, all with normal hearing, comprising 20 pilots in the study group (SG), and 20 non-pilots, not exposed to noise, in the control group (CG). RESULTS: There was no significant difference between groups regarding auditory habits. In the MLD test, a significantly better performance under the homophasic condition (S0N0) was found in the SG. Under the antiphasic condition (SπN0) there were no differences between groups. This combination resulted in a significantly lower MLD in the SG compared to the CG. CONCLUSIONS: Repeated exposure to conditions where active pilots have to learn to recognise speech in noisy backgrounds may lead to a better performance in the MLD's homophasic condition (S0N0).


Assuntos
Militares , Pilotos , Percepção da Fala , Adulto , Limiar Auditivo , Estudos Transversais , Humanos , Masculino , Mascaramento Perceptivo
18.
Chronobiol Int ; 38(7): 944-949, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33779463

RESUMO

South American night monkeys (genus Aotus) are the only nocturnal simian primates. Early activity recordings in North Colombian A. griseimembra monkeys kept under semi-natural conditions and extensive chronobiological studies carried out in laboratory settings revealed a strictly nocturnal behavior and strong activity enhancing (disinhibiting) effects of moonlight or corresponding luminosities during the dark time. To check whether the results from captive individuals correspond to the behavior of wild monkeys, we carried out long-term activity recordings of a wild female A. griseimembra in a tropical rainforest near San Juan de Carare, Northern Colombia. Our data from about 150 days of continuous activity records with an "Actiwatch Mini" (CamNtech, UK) accelerometer-data logger device, confirmed: (1) strictly nocturnal behavior, (2) a pronounced bimodal activity pattern with prominent peaks during dusk and dawn, and (3) a lunar periodic modulation (masking) of the night monkey's circadian activity rhythm due to distinct activity inhibiting effects of the absence of moonlight throughout the night. The results from this wild-living tropical night monkey are consistent with those from captive conspecifics studied decades earlier.


Assuntos
Ritmo Circadiano , Atividade Motora , Animais , Aotidae , Aotus trivirgatus , Colômbia , Feminino , Luz
19.
Laryngoscope ; 131(4): E1227-E1233, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33009672

RESUMO

OBJECTIVES/HYPOTHESIS: To determine the prevalence and associated risk factors of voice disorders in healthcare workers of high-risk hospital care units during the 2019 coronavirus disease (COVID-19) pandemic. STUDY DESIGN: Cross-sectional study. METHODS: Questionnaire survey to healthcare personnel of COVID-19 high-risk hospital units was conducted, regarding demographic data, clinical activity, the pattern of usage of personal protective equipment, medical and vocal history, vocal symptoms, and Spanish validated Voice Handicap Index (VHI)-10 questionnaire. RESULTS: A total of 221 healthcare workers answered the survey. Nearly 33% of them reported having trouble with their voice during the last month, and 26.24% had an abnormal score in the Spanish validated VHI-10 questionnaire. The mean VHI-10 score was 7.92 (95% confidence interval 6.98-8.85). The number of working hours, the number of hours of mask daily use, simultaneous surgical and self-filtering mask use, and working in intermediate or intensive care units were independent variables significantly associated with a higher VHI-10 score. CONCLUSIONS: Healthcare workers of high-risk hospital care units during the universal masking COVID-19 pandemic are at risk of voice disorders. LEVEL OF EVIDENCE: 3 Laryngoscope, 131:E1227-E1233, 2021.


Assuntos
COVID-19/prevenção & controle , Pessoal de Saúde/estatística & dados numéricos , Doenças Profissionais/epidemiologia , Distúrbios da Voz/diagnóstico , Distúrbios da Voz/epidemiologia , Adulto , COVID-19/epidemiologia , COVID-19/transmissão , Estudos Transversais , Feminino , Humanos , Masculino , Equipamento de Proteção Individual , Prevalência , Fatores de Risco , Inquéritos e Questionários
20.
Biol Conserv ; 255: 108996, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36533085

RESUMO

Noise is one of the fastest growing and most ubiquitous type of environmental pollution, with prevalence in cities. The COVID-19 confinement in 2020 in Colombia led to a reduction in human activities and their associated noise. We used this unique opportunity to measure the impacts of noise on urban soundscapes, and explore the effects of urbanization intensity independently of human activity. We launched a community science initiative inviting participants to collect audio recordings from their windows using smartphones. Recordings were taken during severe mobility restrictions (April), and during a period of lightened restrictions (May-June). From the data collected, we measured changes in sound pressure levels (SPL), acoustic structure (soundscape spectro-temporal characteristics), and human perception between the two periods. A 12% increase in human activities had a detectable acoustic footprint, with a significant increase of SPL (2.15 dB, 128% increase), a shift towards dominance of low-frequency broadband signals, and a perceived dominance of human-made over wildlife sounds. Measured changes in SPL and acoustic structure were directly proportional to urbanization; however, perception of these changes was not. This gap may be associated with a masking effect generated by noise or a disconnect of humans from nature in large cities. The mobility restrictions created a chance to better understand the impacts of urbanization and human activities on the soundscape, while raising public awareness regarding noise pollution effects on people and wildlife. Information analyzed here might serve in urban planning in developing countries where urban expansion is occurring in a rapid, unplanned fashion.

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