Comparative Analysis between Conventional Acrylic, CAD/CAM Milled, and 3D CAD/CAM Printed Occlusal Splints.

The development of digital technologies has allowed for the fabrication of new materials; however, it makes it difficult to choose the best methods to obtain occlusal splints with optimal properties, so it is essential to evaluate the effectiveness of these materials. The aim of the study is to compare the fracture resistance of occlusal splints made of different materials after thermo-mechanical aging. METHODS: A total of 32 samples were made from 4 materials (two 3D printed polymeric materials, a PMMA disc for CAD/CAM, and a conventional heat-cured acrylic resin); subsequently, the fracture test was performed using the load compression mode applied occlusally on the splint surface. STATISTICAL ANALYSIS: Four statistical tests were used (Shapiro-Wilk, Levene's test, ANOVA, and Tukey's HSD test). RESULTS: The following study showed that there are differences in fracture strength among the four materials investigated, where the highest strength was observed in the milled splint, with a mean of 3051.2 N (newton) compared to the strength of the flexible splint with 1943.4 N, the printed splint with 1489.9 N, and the conventional acrylic splint with 1303.9 N. CONCLUSIONS: The milled splints were the most resistant to fracture. Of the printed splints, the splint made with flexural rigid resin withstood the applied forces in acceptable ranges, so its clinical indication may be viable. Although the results of this research indicated differences in the mechanical properties between the CAD/CAM and conventional fabrication methods, the selection may also be influenced by processing time and cost, since with a CAD/CAM system there is a significant reduction in the production time of the splint material.

C-2 Thiophenyl Tryptophan Trimers Inhibit Cellular Entry of SARS-CoV-2 through Interaction with the Viral Spike (S) Protein.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes COVID-19, by infecting cells via the interaction of its spike protein (S) with the primary cell receptor angiotensin-converting enzyme (ACE2). To search for inhibitors of this key step in viral infection, we screened an in-house library of multivalent tryptophan derivatives. Using VSV-S pseudoparticles, we identified compound 2 as a potent entry inhibitor lacking cellular toxicity. Chemical optimization of 2 rendered compounds 63 and 65, which also potently inhibited genuine SARS-CoV-2 cell entry. Thermofluor and microscale thermophoresis studies revealed their binding to S and to its isolated receptor binding domain (RBD), interfering with the interaction with ACE2. High-resolution cryoelectron microscopy structure of S, free or bound to 2, shed light on cell entry inhibition mechanisms by these compounds. Overall, this work identifies and characterizes a new class of SARS-CoV-2 entry inhibitors with clear potential for preventing and/or fighting COVID-19.

Determining the Potential of Haematococcus pluvialis Oleoresin as a Rich Source of Antioxidants.

Haematococcus pluvialis is known to be a natural source of antioxidants for numerous applications. In this study, an oleoresin rich in carotenoids extracted by supercritical CO2 treatment of H. pluvialis was extensively characterized for its antioxidant capacity. Carotenoid content, fatty acid profile, total phenol content, antioxidant capacity, and viscosity of the oleoresin were determined with the aim of ascertaining the potential of the oleoresin in terms of its antioxidant content for food applications. The oleoresin contained 96.22 mg/g of total astaxanthin (which includes free astaxanthin and astaxanthin esters) and mostly included unsaturated fatty acids (~78% of total fatty acids). High total phenol content and ferric reducing antioxidant potential indicated high antioxidant capacity, but oxygen radical absorbance capacity was lower compared to the oleoresin samples obtained from other species. The oleoresin was a non-Newtonian fluid since it had shear-thinning (pseudoplastic) and shear-thickening (dilatant) flow. Therefore, the H. pluvialis oleoresin is a potential alternative in developing functional ingredients for designing healthy food products. To the best of our knowledge, this is the first study that has reported an extensive characterization of the antioxidant properties of a microalgal oleoresin obtained by means of supercritical CO2 fluid extraction.

Análisis de haplotipos de la tortuga cabezona Caretta caretta (Testudines: Cheloniidae) en dos playas del Caribe colombiano / Analysis of haplotypes of the loggerhead turtle, Caretta caretta (Testudines: Cheloniidae), on two beaches of the Colombian Caribbean / Análise de haplotipos da tartaruga cabeçona, Caretta caretta (Testudines: Cheloniidae) em duas praias do Caribe colombiano

Resumen Introducción. La tortuga Caretta caretta habita los mares tropicales y subtropicales. Es una especie en vía de extinción que anida las playas en Colombia y hace extensas migraciones. Los haplotipos mitocondriales de esta tortuga se han utilizado para estudios de genética poblacional, filogeografía y estado de las especies con el objetivo de desarrollar planes de conservación de la especie. Objetivo. Identificar haplotipos mitocondriales en tortugas cabezonas anidantes del Caribe colombiano. Materiales y Métodos. Se recolectaron muestras de sangre periférica de esta especie en dos sitios del Caribe colombiano: Don Diego (playa de anidación) y la Isla San Martin de Pajarales (localidad de alimentación). El ADN total fue extraído a partir de las células sanguíneas, y utilizado para amplificar por PCR la región control mitocondrial (398 pb). Estos productos fueron purificados y secuenciados. Se realizó un alineamiento básico buscando regiones de similitud local entre las secuencias obtenidas y las descritas previamente para la especie. Se hicieron análisis filogenéticos utilizando los criterios de máxima parsimonia (MP) y máxima verosimilitud (ML). Resultados. Se identificaron tres haplotipos, CC-A1 y CC-A2 comúnmente encontrados en poblaciones reproductivas de México, el Mediterráneo y el sudeste de Estados Unidos, y un nuevo haplotipo CC-SM1 en la playa Don Diego (Magdalena). Los árboles filogenéticos muestran relación de una porción de los individuos anidantes y de forrajeo de las agregaciones del Caribe colombiano con las súper-agregaciones del Atlántico y el Mediterráneo, sugiriendo que estas podrían ser algunas de las fuentes importantes de individuos presentes en Colombia. Conclusiones. Es necesario estudiar una muestra más grande para poder confirmar hipótesis planteadas. Se identificó un nuevo haplotipo denominado CC-SM1. Este es el primer estudio sobre haplotipos mitocondriales de C. caretta realizado en Colombia.

Abstract Introduction. The Caretta caretta turtle inhabits tropical and subtropical seas. It is an endangered species that nests on Colombian beaches and makes long migrations. The mitochondrial haplotypes of this turtle have been used for population genetics, phylogeography and species status studies with the aim of developing species conservation plans. Objective. Identify mitochondrial haplotypes in nesting loggerhead turtles from the Colombian Caribbean. Materials and Methods. Peripheral blood samples from this species were collected in two sites of the Colombian Caribbean: Don Diego (nesting beach) and San Martin de Pajarales island (feeding ground). The total DNA was extracted from blood cells and used to amplify the mitochondrial control region by PCR (398 bp). These products were purified and sequenced. A basic alignment was performed looking for local similarity regions between the sequences obtained and those previously described for the species. Phylogenetic analyses were conducted by using the maximum parsimony (MP) and maximum likelihood (ML) criteria. Results. Three haplotypes were identified: CC-A1 and CC-A2, which are commonly found in breeding populations in Mexico, the Mediterranean and southeast U.S.; and a new haplotype, CC-SM1, on the Don Diego beach (Magdalena). The phylogenic trees show a relationship between a portion of the nesting and feeding individuals from the Colombian Caribbean aggregations and the Atlantic and Mediterranean super-aggregations, suggesting that these could be some of the important sources for individuals inhabiting Colombia. Conclusions. It is necessary to study a larger sample to be able to confirm the proposed hypotheses. A new haplotype called CC-SM1was identified. This is the first study on C. caretta mitochondrial haplotypes conducted in Colombia.

Resumo Introdução. A tartaruga Caretta caretta habita os mares tropicais e subtropicais. É uma espécie em via de extinção que enraíza as praias na Colômbia e faz extensas migrações. Os haplotipos mitocondriais desta tartaruga se há utilizado para estudos de genética populacional, fílogeografía e estado das espécies com o objetivo de desenvolver planos de conservação da espécie. Objetivo. Identificar haplotipos mitocondriais em tartarugas cabeçonas enraizada no Caribe colombiano. Materiais e Métodos. Se coletaram amostras de sangue periférica desta espécie em dois lugares do Caribe colombiano: Don Diego (praia de enraizamento) e a Ilha San Martin de Pajarales (localidade de alimentação). O DNA total foi extraído a partir das células sanguíneas, e utilizado para amplificar por PCR a região controle mitocondrial (398 pb). Estes produtos foram purificados e sequenciados. Se realizou um alinhamento básico buscando regiões de semelhança local entre as sequências obtidas e as descritas previamente para a espécie. Se fez análise filogenéticos utilizando os critérios de máxima parcimônia (MP) e máxima verossimilitude (ML). Resultados. Se identificaram três haplotipos, CC-A1 e CC-A2 comumente encontrados nas populações reprodutivas do México, o Mediterráneo e o sudeste de Estados Unidos, e um novo haplotipo CC-SM1 na praia Don Diego (Magdalena). As árvores filogenéticos mostram relação de uma porção dos indivíduos enraizados e de forragem das agregações do Caribe colombiano com as super-agregações do Atlântico e o Mediterrâneo, sugerindo que estas poderiam ser algumas das fontes importantes de indivíduos presentes na Colômbia. Conclusões. É necessário estudar uma amostra maior para poder confirmar hipótese proposta. Se identificou um novo haplotipo denominado CC-SM1. Este é o primeiro estudo sobre haplotipos mitocondriais de C. caretta realizado na Colômbia.

Infant difficulty and early weight gain: does fussing promote overfeeding?

Authors have recently suggested that difficult temperament in infancy may be associated with rapid weight gain, but no previous studies actually report associations between temperament and feeding as a response to infant distress. The purpose of the present study was to examine whether greater infant difficulty elicits more feeding, which in turn leads to more rapid weight gain in early infancy. One hundred fifty-four mother-infant pairs were visited at 3 and 6 months in their homes. Besides anthropometric measures, mothers kept a 24-h diary of their infants' sleep, cry and feed patterns, and answered questions regarding feeding and infant difficultness. The results showed that feeding occurred as a response to nearly half (48%) of the crying intervals recorded, though it more often occurred in the absence of crying (83%). Mothers were most likely to report holding or rocking their infant as the first strategy they would employ if their baby fussed or cried. A regression analysis that included crying, feeding, weaning, sleep and infant weight revealed maternal reports of numbers of feeds per day as the only variable that predicted weight gain from 3 to 6 months. Infant crying is often followed by feeding, and more frequent feeding may promote more rapid weight gain. However, feeding frequency in the first few months appears to be more a matter of maternal discretion than a yoked response to temperamental difficulty. This does not preclude the possibility that overfeeding in later infancy could be tied to temperamental difficulty and subsequently related to overweight in early childhood.

Child outdoor physical activity is reduced by prevalence of the Asian tiger mosquito, Aedes albopictus.

We tested the hypothesis that day-biting mosquitoes contribute to child obesity by reducing opportunities for summer outdoor play. The influence of Asian tiger mosquito (Aedes albopictus) prevalence on child outdoor physical activity was compared in 2 matched urban communities, one treated for mosquito abatement and one untreated. More time was spent outdoors by children where abatement took place.

Compromiso mamario bilateral por leucemia linfocítica aguda. Hallazgos por mamografía, ultrasonido y resonancia magnética: Presentación de un caso / Bilateral breast involvement in acute lymphoblastic leukemia. Mammographic, ultrasound and magnetic resonance imaging findings: Case report

Presentamos el caso de una paciente de 26 años de edad con antecedente de leucemia linfocítica aguda, tratada con quimioterapia y trasplante de médula ósea, que consultó por nódulos palpables en ambas mamas. Se estudió mediante mamografía, ultrasonido (US) y resonancia magnética (RM), y el diagnóstico anatomopatológico final fue una recaída de la enfermedad de base por compromiso mamario. El caso resulta de interés, ya que se trata de una forma de manifestación muy poco habitual, con escasos reportes en la literatura y ningún trabajo encontrado en el que se describa la utilidad de la resonancia magnética en estos pacientes.

We report a case of a 26-year-old girl with acute lymphoblastic leukemia treated with chemotherapy and bone marrow transplant who presented with palpable lumps in both breasts. Mammography, ultrasound and magnetic resonance imaging were performed, with the final pathological diagnosis being relapse of her underlying disease with breast involvement. The case is worth reporting because it is a very unusual form of presentation, with few reports in medical literature, having found no previous studies discussing the usefulness of magnetic resonance imaging in these cases.

Compromiso mamario bilateral por leucemia linfocítica aguda. Hallazgos por mamografía, ultrasonido y resonancia magnética: Presentación de un caso / Bilateral breast involvement in acute lymphoblastic leukemia. Mammographic, ultrasound and magnetic resonance imaging findings: Case report

Presentamos el caso de una paciente de 26 años de edad con antecedente de leucemia linfocítica aguda, tratada con quimioterapia y trasplante de médula ósea, que consultó por nódulos palpables en ambas mamas. Se estudió mediante mamografía, ultrasonido (US) y resonancia magnética (RM), y el diagnóstico anatomopatológico final fue una recaída de la enfermedad de base por compromiso mamario. El caso resulta de interés, ya que se trata de una forma de manifestación muy poco habitual, con escasos reportes en la literatura y ningún trabajo encontrado en el que se describa la utilidad de la resonancia magnética en estos pacientes.(AU)

We report a case of a 26-year-old girl with acute lymphoblastic leukemia treated with chemotherapy and bone marrow transplant who presented with palpable lumps in both breasts. Mammography, ultrasound and magnetic resonance imaging were performed, with the final pathological diagnosis being relapse of her underlying disease with breast involvement. The case is worth reporting because it is a very unusual form of presentation, with few reports in medical literature, having found no previous studies discussing the usefulness of magnetic resonance imaging in these cases.(AU)

Feeding Practices of Mothers from Varied Income and Racial/Ethnic Groups.

OBJECTIVE: Relatively few investigators have explored the role of maternal control in describing the feeding behavior of nonwhite parents of preschool-age children. The present study was conducted to examine if controlling feeding behaviors (i.e., restriction and pressuring) varied by income (middle vs. low) and race/ethnicity (white vs. Hispanic), and if they were associated with the BMI of their 4-year-old offspring. METHOD: Responses to the "restriction" and "pressure to eat" variables of the Child Feeding Questionnaire were compared between 51 white middle-income mothers and 49 Hispanic low-income mothers. RESULTS: Mothers from both groups gave predominantly "neutral" ratings in their self-reports of feeding practices. However, relative to the Hispanic mothers, white mothers indicated significantly less restriction and pressure to eat. Higher child BMI was predicted by male gender and being Hispanic. CONCLUSION: The utility of maternal feeding practices in predicting child overweight is discussed, and the significant association between the conceptually different constructs of restriction and pressure to eat is examined.