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1.
Pharmaceutics ; 16(4)2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38675152

RESUMEN

Severe loss of bone mass may require grafting, and, among the alternatives available, there are natural biomaterials that can act as scaffolds for the cell growth necessary for tissue regeneration. Collagen and elastin polymers are a good alternative due to their biomimetic properties of bone tissue, and their characteristics can be improved with the addition of polysaccharides such as chitosan and bioactive compounds such as jatoba resin and pomegranate extract due to their antigenic actions. The aim of this experimental protocol was to evaluate bone neoformation in experimentally made defects in the mandible of rats using polymeric scaffolds with plant extracts added. Thirty rats were divided into group 1, with a mandibular defect filled with a clot from the lesion and no graft implant (G1-C, n = 10); group 2, filled with collagen/chitosan/jatoba resin scaffolds (G2-CCJ, n = 10); and group 3, with collagen/nanohydroxyapatite/elastin/pomegranate extract scaffolds (G3-CHER, n = 10). Six weeks after surgery, the animals were euthanized and samples from the surgical areas were submitted to macroscopic, radiological, histological, and morphometric analysis of the mandibular lesion repair process. The results showed no inflammatory infiltrates in the surgical area, indicating good acceptance of the scaffolds in the microenvironment of the host area. In the control group (G1), there was a predominance of reactive connective tissue, while in the grafted groups (G2 and G3), there was bone formation from the margins of the lesion, but it was still insufficient for total bone repair of the defect within the experimental period standardized in this study. The histomorphometric analysis showed that the mean percentage of bone volume formed in the surgical area of groups G1, G2, and G3 was 17.17 ± 2.68, 27.45 ± 1.65, and 34.07 ± 0.64 (mean ± standard deviation), respectively. It can be concluded that these scaffolds with plant extracts added can be a viable alternative for bone repair, as they are easily manipulated, have a low production cost, and stimulate the formation of new bone by osteoconduction.

2.
BMC Med Educ ; 24(1): 47, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38200477

RESUMEN

BACKGROUND: Medical education has evolved based on the application of pedagogical actions that place the student as the protagonist of the learning process through the use of active teaching methodologies. Within this context, higher education teachers should use strategies that focus on the student and his/her context and avoid traditional teaching methods. Specifically in medical schools, there is an even greater challenge since the teaching methods of medical curricula differ from those used in previous schooling. Consequently, students acquire their own style of processing information that is often incompatible with the profile of medical schools. This may be one of the factors responsible for the lack of motivation among undergraduates. OBJECTIVE: The aim of this study was to characterize the learning styles of students enrolled in a Brazilian medical school using the Felder-Soloman Index of Learning Styles (ILS). METHODS: This was a cross-sectional, descriptive, quantitative study that included students from the 1st to the 6th year of a Brazilian medical school. The students participating in this study voluntarily answered 44 questions about learning styles of the Felder-Silverman instrument validated in Brazil. The instrument was divided so that each domain consisted of 11 questions with two response options in which only one could be selected. For each domain, a score (1 point) was assigned to the selected option (a, b) of the question and the learning style category was determined as the difference between these values. For data collection and tabulation, we used the Learning Syle Platform (EdA Platform) developed based on Felder's studies since this system processes information about the dimension analyzed, the preferred style, and the most striking characteristics of each style. RESULTS: The results showed that sensing was the preferred learning style of the students, followed by the sequential and visual styles. It was not possible to determine whether gender or age influences the choice of learning methods because of the homogeneity of the results. CONCLUSIONS: The present data will enable teachers of the institution involved in this study to plan pedagogical actions that improve the students' self-awareness, as well as their teaching-learning skills, by choosing the most adequate active methodologies for the medical education programs considering the individuality of each student and class.


Asunto(s)
Estudiantes de Medicina , Femenino , Humanos , Masculino , Brasil , Estudios Transversales , Aprendizaje , Escolaridad
3.
Int J Mol Sci ; 23(12)2022 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-35742948

RESUMEN

Biomaterials have been investigated as an alternative for the treatment of bone defects, such as chitosan/carbon nanotubes scaffolds, which allow cell proliferation. However, bone regeneration can be accelerated by electrotherapeutic resources that act on bone metabolism, such as low-level laser therapy (LLLT). Thus, this study evaluated the regeneration of bone lesions grafted with chitosan/carbon nanotubes scaffolds and associated with LLLT. For this, a defect (3 mm) was created in the femur of thirty rats, which were divided into 6 groups: Control (G1/Control), LLLT (G2/Laser), Chitosan/Carbon Nanotubes (G3/C+CNTs), Chitosan/Carbon Nanotubes with LLLT (G4/C+CNTs+L), Mineralized Chitosan/Carbon Nanotubes (G5/C+CNTsM) and Mineralized Chitosan/Carbon Nanotubes with LLLT (G6/C+CNTsM+L). After 5 weeks, the biocompatibility of the chitosan/carbon nanotubes scaffolds was observed, with the absence of inflammatory infiltrates and fibrotic tissue. Bone neoformation was denser, thicker and voluminous in G6/C+CNTsM+L. Histomorphometric analyses showed that the relative percentage and standard deviations (mean ± SD) of new bone formation in groups G1 to G6 were 59.93 ± 3.04a (G1/Control), 70.83 ± 1.21b (G2/Laser), 70.09 ± 4.31b (G3/C+CNTs), 81.6 ± 5.74c (G4/C+CNTs+L), 81.4 ± 4.57c (G5/C+CNTsM) and 91.3 ± 4.81d (G6/C+CNTsM+L), respectively, with G6 showing a significant difference in relation to the other groups (a ≠ b ≠ c ≠ d; p < 0.05). Immunohistochemistry also revealed good expression of osteocalcin (OC), osteopontin (OP) and vascular endothelial growth factor (VEGF). It was concluded that chitosan-based carbon nanotube materials combined with LLLT effectively stimulated the bone healing process.


Asunto(s)
Quitosano , Terapia por Luz de Baja Intensidad , Nanotubos de Carbono , Animales , Regeneración Ósea , Ratas , Ratas Wistar , Andamios del Tejido , Factor A de Crecimiento Endotelial Vascular/metabolismo
4.
Polymers (Basel) ; 14(1)2022 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-35012210

RESUMEN

The aim of the present study was to evaluate the use of collagen, elastin, or chitosan biomaterial for bone reconstruction in rats submitted or not to experimental alcoholism. Wistar male rats were divided into eight groups, submitted to chronic alcohol ingestion (G5 to G8) or not (G1 to G4). Nasal bone defects were filled with clot in animals of G1 and G5 and with collagen, elastin, and chitosan grafts in G2/G6, G3/G7, and G4/G8, respectively. Six weeks after, all specimens underwent radiographic, tomographic, and microscopic evaluations. Bone mineral density was lower in the defect area in alcoholic animals compared to the abstainer animals. Bone neoformation was greater in the abstainer groups receiving the elastin membrane and in abstainer and alcoholic rats receiving the chitosan membrane (15.78 ± 1.19, 27.81 ± 0.91, 47.29 ± 0.97, 42.69 ± 1.52, 13.81 ± 1.60, 18.59 ± 1.37, 16.54 ± 0.89, and 37.06 ± 1.17 in G1 to G8, respectively). In conclusion, osteogenesis and bone density were more expressive after the application of the elastin matrix in abstainer animals and of the chitosan matrix in both abstainer and alcoholic animals. Chronic alcohol ingestion resulted in lower bone formation and greater formation of fibrous connective tissue.

5.
Hig. aliment ; 33(288/289): 403-407, abr.-maio 2019. ilus
Artículo en Portugués | LILACS, VETINDEX | ID: biblio-1481965

RESUMEN

O objetivo do estudo foi mapear o processo de fabricação do pão francês em uma indústria de massas congeladas de Fortaleza–CE. Foram realizadas análise dos documentos e ficha técnica, observação das etapas de fabricação para a elaboração do fluxo de produção, mapeamento e desenho do processo utilizando a planilha 5W2H e aplicação da árvore decisória como ferramenta para análise de perigos e pontos críticos de controle (APPCC). Quanto a identificação dos pontos críticos de controle (PCC), foram observados nas etapas de homogeneização e embalagem/detector de metais do fluxo de produção. Contudo, o estudo possibilitou ainda, a adoção das medidas de controle em tempo hábil, minimizando os riscos de contaminação do alimento, tornando-se viável a implantação do Sistema APPCC, de modo a assegurar a qualidade do produto final.


Asunto(s)
Análisis de Peligros y Puntos de Control Críticos , Flujo de Trabajo , Industria de Alimentos , Pan , Alimentos Congelados , Pastas Alimenticias
6.
Arch Biochem Biophys ; 658: 46-53, 2018 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-30222952

RESUMEN

Plant ribosome-inactivating proteins (RIPs) are a family of toxins that inhibit protein synthesis. In this study, we have isolated a novel type 2 ribosome-inactivating protein (RIP) present in seeds of the Abrus fruticulosus, named of fruticulosin. Fruticulosin, shows characteristics common to other type 2 RIPs, as specificity by galactosides (d-galactose, N-acetyl-d-galactosamine, and d-lactose), mass of approximately 60 kDa and presence of the of disulfide bonds. The N-terminal amino acid sequence (26 residues) of A-chain fruticulosin, determined by Edman degradation, revealed high similarity of the A-chain with those of other type 2 RIPs. The secondary structure of fruticulosin was analysed by circular dichroism, which showed that fruticulosin contains α-helices (22.3%), ß-sheets (43.5%), and random coils and corners (34.2%). Furthermore, fruticulosin showed high toxicity in Artemia sp. (3.12 µg/mL), inhibited in vitro protein synthesis by a cell-free system and showed RNA N-glycosidase activity. Fruticulosin presented biological activities such as agglutination and antileishmanial activity on promastigote forms of Leishmania major.


Asunto(s)
Abrus/química , Proteínas de Plantas/farmacología , Proteínas Inactivadoras de Ribosomas/farmacología , Tripanocidas/farmacología , Secuencia de Aminoácidos , Animales , Artemia/efectos de los fármacos , Hemaglutininas/química , Hemaglutininas/aislamiento & purificación , Hemaglutininas/farmacología , Hemaglutininas/toxicidad , Leishmania major/efectos de los fármacos , Ratones , Pruebas de Sensibilidad Parasitaria , Proteínas de Plantas/química , Proteínas de Plantas/aislamiento & purificación , Proteínas de Plantas/toxicidad , Inhibidores de la Síntesis de la Proteína/química , Inhibidores de la Síntesis de la Proteína/aislamiento & purificación , Inhibidores de la Síntesis de la Proteína/farmacología , Inhibidores de la Síntesis de la Proteína/toxicidad , Conejos , Proteínas Inactivadoras de Ribosomas/química , Proteínas Inactivadoras de Ribosomas/aislamiento & purificación , Proteínas Inactivadoras de Ribosomas/toxicidad , Semillas/química , Homología de Secuencia de Aminoácido , Tripanocidas/química , Tripanocidas/aislamiento & purificación , Tripanocidas/toxicidad
7.
Arq. Inst. Biol ; 82: 1-7, 2015. tab, graf
Artículo en Portugués | LILACS, VETINDEX | ID: biblio-1025980

RESUMEN

O objetivo deste trabalho foi avaliar a qualidade da água de granjas de postura comercial da região Sul de Santa Catarina e contextualizá-la com o Ofício Circular Conjunto DFIP/DSA nº 1/2008. Em fevereiro de 2012 foram coletadas amostras de água de 31 granjas localizadas nos municípios de São Ludgero, Orleans, Grão Pará e Braço Norte. Os parâmetros químicos e microbiológicos avaliados foram os estabelecidos no anexo II do Oficio Circular Conjunto DFIP/DSA nº 1/2008. Sendo assim foram analisados cloreto, dureza, nitrato, sulfato, pH e sólidos dissolvidos totais (SDT) e Escherichia coli no que se refere à análise bacteriológica. Quantificou-se a adequação das amostras em relação ao Ofício Circular Conjunto DFIP/DSA nº 1/2008 e avaliou-se a qualidade da água de acordo com o tipo de fonte e número de aves em produção por meio da análise de variância. Os resultados indicaram que as águas apresentaram adequação para SDT, cloreto e sulfato. Foi encontrada inadequação nos parâmetros: pH (em 26% das amostras), dureza (6,5%), nitrato (54,8%) e presença de Escherichia coli (46,2%). As análises de acordo com o número de aves e tipo de fonte não apresentaram diferença estatística significativa (p > 0,05). Observaram-se que 93,5% das amostras não se enquadraram em pelo menos um parâmetro. Concluíram-se que as águas das granjas da Região Sul de SC não estão totalmente de acordo com o Ofício Circular Conjunto DFIP/DSA nº 1/2008, apresentando problemas no que se refere ao pH, dureza, nitrato e E. coli; a qualidade da água independe do número de aves em produção e do tipo de fonte que abastece a granja.(AU)


The aim of this study was to evaluate the water quality of laying hen farms in the South of Santa Catarina and contextualize them with the report DFIP/DSA 1/2008. Water samples were collected in February, 2012, from 31 farms located in the cities of São Ludgero, Orleans, Grão Para and Braço Norte. The chemical and microbiological parameters were set out in Attachment II, in the report DFIP/DSA 1/2008. Thus, the following were analyzed: chloride, hardness, nitrate, sulfate, pH and total dissolved solids (TDS) and Escherichia coli regarding the bacteriological analysis. The suitable samples were quantified for the report DFIP/DSA 1/2008 and water quality was evaluated according to the font type and number of birds in production by analysis of variance. The results indicated that water presented suitability to SDT, chloride and sulfate. Inadequacy was found in pH (in 26% of samples), hardness (6.5%), nitrate (54.8%) and the presence of Escherichia coli (46.2%). The analysis according to the number of birds and font type showed no statistically significant differences (p > 0.05). It was observed that 93.5% of the samples did not fit in at least one criterion. It is concluded that the waters from farms in the southern region of SC are not fully in accordance with the report DFIP/DSA 1/2008, presenting problems with regard to pH, hardness, nitrate and E. coli; the water quality is independent of the number of birds in production and type of source that supplies the farm.(AU)


Asunto(s)
Aves de Corral , Criterios de Calidad del Agua , Control de la Calidad del Agua , Escherichia coli , Fenómenos Biológicos
8.
Surg Endosc ; 26(11): 3195-200, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22609982

RESUMEN

BACKGROUND: Elevations of intraabdominal pressure during laparoscopic procedures may lead to oliguria or anuria in mammals. Despite this, previous research has not been able to confirm an associated kidney injury. This study aimed to investigate the occurrence of an early kidney lesion secondary to surgical pneumoperitoneum in a rat model using the expression of neutrophil gelatinase-associated lipocalin (N-GAL) as a biomarker for early kidney injury. METHODS: In this study, 20 male Sprague-Dawley rats under general anesthesia and mechanically ventilated were allocated to one of five experimental time-dependent groups: group 1 (1-h control), group 2 (1-h pneumoperitoneum), group 3 (2-h control), group 4 (2-h pneumoperitoneum), and group 5 (positive kidney injury group induced by intravenous administration of cisplatin 7.5 mg/kg). To evaluate the renal expression of N-GAL 24 h after the procedure, all the rats underwent a 2-h urine output evaluation as well as laparotomy and bilateral nephrectomy performed sequentially to investigate the presence of renal injury using immunofluorescence qualification and western blotting. RESULTS: Urine output was reduced and N-GAL expression was increased in the animals from the cisplatin group. The animals undergoing 1- or 2-h pneumoperitoneum displayed urine output and N-GAL expression similar to that of the animals from the matching control groups. CONCLUSIONS: Under the experimental conditions of this study, the animals with normal preoperative renal function did not show any type of acute kidney injury associated with the presence of a stabilized surgical pneumoperitoneum.


Asunto(s)
Lesión Renal Aguda/etiología , Neumoperitoneo Artificial/efectos adversos , Lesión Renal Aguda/metabolismo , Proteínas de Fase Aguda/análisis , Proteínas de Fase Aguda/biosíntesis , Animales , Biomarcadores/análisis , Lipocalina 2 , Lipocalinas/análisis , Lipocalinas/biosíntesis , Masculino , Proteínas Proto-Oncogénicas/análisis , Proteínas Proto-Oncogénicas/biosíntesis , Ratas , Ratas Wistar , Orina
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