Este trabalho teve como objetivo preparar e caracterizar um compósito de colágeno com silicato e hidroxiapatita a ser possivelmente utilizado para capeamento pulpar direto e em pulpotomia como material endodôntico em prevenção ao tratamento radical de canais radiculares que em virtude de suas anatomias dificultam a utilização de biomateriais no interior dos mesmos. Embora materiais para este fim estejam disponíveis no mercado, na maioria dos casos não são isentos de agressão na zona do reparo. O colágeno utilizado foi do tipo I na forma aniônica que foi misturado com silicato (cimento Portland branco) e hidroxiapatita em proporções variadas. Os materiais obtidos foram caracterizados por técnicas de calorimetria exploratória diferencial (DSC), termogravimetria (TG), microscopia eletrônica de varredura (MEV), espectrometria de dispersão de energia de Raios-X (EDX) e espectroscopia na região do infravermelho (FTIR). A presença de colágeno no compósito foi demonstrada por transições térmicas típicas daquelas encontradas para o colágeno do tipo I ('APROXIMADAMENTE' 48 graus Celsius), independentemente da proporção utilizada, e também por MEV, onde as fibras colagênicas também puderam ser observadas interligando as partículas de silicato. Em função das quantidades de colágeno utilizadas, a composição química dos compósitos foi praticamente aquela descrita para o silicato inicial utilizado. Estes resultados mostraram que a estrutura da matriz colagênica nos compósitos estudados não foi alterada, uma característica importante para a utilização dos materiais propostos na endodontia objetivando uma reparação dos tecidos envolvidos de uma forma “mais natural” / In this work was prepared and characterized collagen composites with silicate and hydroxyapatite for pulp capping; post pulpotomy usage, as endodontic material. Even though materials for this purpose are available, in most case they suffer degradation in the repair zone when. Was used type I collagen in the form anionic mixed with silicate (white Portland cement) and hydroxyapatite in various proportions. The materials were characterized by standard differential scanning calorimetry (DSC), thermogravimetry (TG), scanning electronic microscopy (SEM) and infrared spectroscopy (FTIR), energy dispersion X-Ray (EDX). The presence of the collagen in the composite was checked via the thermal transitions typical for collagen type I ('APPROXIMATE' 48 Celsius degrees), independently of the proportion used and also via MEV, in which the collagenic fibers could also be seen interconnecting the silicate particles. For the amounts of collagen used, we find the chemical composition of the composites is essentially the same as that of the silicate we started with. This results showed that the structure of the collagenic matrix in the composite studied is not altered – an important feature for the use of the proposed materials in endodontic applications aiming at repairing the relevant tissues in a “more natural way”

A relação entre as propriedades mecânicas de fêmures de celhos obtidas nos ensaios de flexão em três pontos e impacto, e a orientação das fibras de colágeno foi estudada, bem como a relação entre a energia absorvida nos dois ensaios. O limite máximo, limite proporcional, rigidez, resiliência e tenacidade foram obtidos a partir de ensaio de flexão em três pontos de 20 fêmures esquerdos de coelhos. A energia absorvida (tenacidade) no impacto foi obtida utilizando os 20 fêmures direitos. A orientação das fibras de colágeno foi estimada utilizando a técnica de polarização da luz incidente. A análise de regressão mostrou que no ensaio de flexão, a rigidez teve correlação positiva (R=0,43) e a resiliência, correlação negativa (R=-0,46) com a orientação das fibras de colágeno. A energia absorvida no impacto não apresentou índice de correlação significativo (p<0,05). A energia absorvida no ensaio de impacto pelos fêmures foi 4,73 vezes a energia absorvida ensaio de flexão, havendo diferença significativa entre os dois valores / The relationship between the mechanical properties of rabbit femurs in three-point bending and impact tests and collagen fiber orientation was studied, as well as the proportion between absorbed energy in both tests. Maximum limit, proportional limit, stiffness and resiliency were measured in 20 left rabbit femurs by three point bending tests and the absorbed energy was measured in 20 right rabbit femurs by impact tests. Collagen fiber orientation was estimated using polarized light. Regression analysis showed that in bending, stiffness has significant positive correlation (R=0,43) and resiliency has significant negative correlation (R=-0,46) with collagen fiber orientation. Absorbed energy in impact showed no significant correlation with collagen fiber orientation. The absorbed energy in impact tests was 4,73 times the absorbed energy in three point bending tests, with significant difference between the two values

O Callithrix jacchus é uma espécie nativa do Brasil que vem sendo amplamente utilizada nas pesquisas biomédicas como modelo experimental, além de estar sofrendo significativas baixas na natureza, especialmente, pela destruição de seu habitat. Assim, estudou-se corações de 11 espécimes de Callithrix jacchus oriundos do Centro de Primatas da Alemanha (DPZ), para a caracterização biométrica, morfométrica macroscópica e quantificação de colágeno dos ventrículos direito e esquerdo corados com finalidade de identificar o padrão primário deste tecido para a espécie e compará-lo com outras espécies domésticas e o homem. Com base nos resultados, concluiu-se que não há diferenças biométricas significativas entre machos e fêmeas, exceto pelo perímetro torácico que evidenciou dimorfismo sexual para a espécie. Os pesos relativos dos corações foram semelhantes aos encontrados na espécies humana, bovina e eqüina. A morfometria média do coração foi estabelecida sem diferenças significativas entre machos e fêmeas. A quantificação de colágeno apresentou diferenças significativas entre as duas colorações utilizadas, sendo o picrosírius modificado o método que apresentou maiores valores. O ventrículo direito continha maior percentagem de colágeno quando comparado ao ventrículo esquerdo o que sugere que o ventrículo direito está mais predisposto a alterações decorrentes de modificações do tecido conjuntivo / The Callithrix jacchus is Brazil native species wich is being widely used as experimental model in biomedical research, besides facing great losses, especially through the destruction of its habitat. Accordingly, 11 hearts of Callitrix jacchus from the Center of Primates in Germany (DPZ) have been studied, in order to establish a biometrical characterization, gross morphometry and collagen quantification of the left and the right ventricle to establish a prime pattern for this species and compare it with other domestic species and human. Based on the obtained results, no significant biometrical difference was found between male and female, just the thoracic perimeter showed sexual dimorphism. The relative heart weight was similar to the one measured in human, bovine and equine species. The average morphometry of the hearts did not show any significant difference between male and female. The collagen quantification established a difference between the used colorings, evidencing the modified picrosirius presented higher values. The right ventricle contained a higher percentage of collagen compared with the left one, indicating the right ventricle to be more predisposed to alterations of the modified connective tissue

Recentemente, pesquisadores têm descrito resultados promissores oriundos da Biomembrana de Látex Natural (BML). Estudos vêm sendo desenvolvidos para comprovar as características indutoras de neovascularização e regeneração tecidual que foram atribuídas a esse material. Entretanto, a biocompatibilidade tem sido considerada um dos mais importantes itens para validar um biomaterial para sua aplicação em humanos. A proposta deste estudo foi investigar qualitativa e quantitativamente os efeitos deste biopolímero, confeccionado à partir da extração de látex vegetal oriundos da árvore da borracha, Hevea brasiliensis, em pele de ratos escaldados. Foram usados 22 ratos, Wistar machos, com pesos entre 200 e 300g, divididos em três grupos: Controle negativo - normais (GI), Controle positivo - queimados (GII) e Tratados com a BML (GIII). A lesão térmica foi realizada por escaldamento (LTE), padronizada pelo peso corpóreo e usando água quente (85ºC for 10 segundos), e a ortoeutanásia dos animais ocorreu nos períodos de 4 e 14 dias pós-lesão. Os animais foram mantidos sob as mesmas condições de alojamento, alimentação, temperatura, umidade e luz. O grupo GIII apresentou melhor cicatrização comparado àqueles do grupo GII. Observou-se que as fibras colágenas e elásticas apresentaram-se em uma rede melhor organizada no grupo GIII e observou-se, ainda, que o número de vasos também foi maior neste grupo. Como vistos em estudos anteriores, a BML favoreceu a cicatrização em áreas queimadas e a neoangiogênese, sugerindo que este biomaterial é um promissor recurso terapêutico para a cicatrização da pele, particularmente nos casos em que a revascularização tecidual seja importante. / Recent investigations have described promising results obtained with the Natural Latex Biomembrane (BML). Several studies had been performed to prove the inductive characteristics of vascularization and tissue regeneration that has been attributed to this material. However biocompatibility has been considered one of the most important items to validate a biomaterial for its application in human beings. The aim of this study was to investigate qualitatively and quantitatively the effects of a biopolymer based on vegetal latex extracted from the Hevea brasiliensis rubber tree in scalded rat skin. Twenty two male Wistar rats weighing between 200 300 g, were divided in three groups: Negative control - normal (GI), Positive control - scalded (GII), and Treated with the BML (GIII). The thermal burn standardized with the body weight, was made using hot water (85ºC for 10 seconds). Euthanasia was performed at 4, and 14 days pos-burn. Animals were kept under the same conditions of accommodation, feeding, temperature, humidity, and light. The burn area with satisfactory healing was greater in GIII than in GII. Collagen and elastic fibers could be seen in a very organized fashion in GIII group, in a similar arrangement that GI. The number of vessels was higher in GIII that others groups. Similar to earlier studies, the BML seemed to benefit cicatrization and neoangiogenesis in the burn skin, suggesting that this biomaterial might be a new type of therapeutic resource for skin burn replacement, especially in cases of desirable tissue revascularization.

京都大学 / 0048 / 新制・論文博士 / 博士(医学) / 乙第13265号 / 論医博第2179号 / 新制||医||1038(附属図書館) / (主査)教授 別所 和久, 教授 安達 泰治, 教授 戸口田 淳也 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM

El presente estudio se desarrolló con el propósito de implementar una idea de negocio escalable, visionaria y atractiva / a raíz de esto, se realizó una investigación de mercado a fin de obedecer las tendencias y responder a las demandas insatisfechas. Los resultados del análisis señalaron que: las personas se mantienen en constante búsqueda de productos saludables y de fácil consumo, aprecian más los alimentos naturales que los procesados, prestan especial atención al valor nutricional de lo que ingieren y demuestran empatía de cara al medio ambiente. Ante esto, se consolidó la propuesta referida al lanzamiento de una bebida frutada 100% natural a base de colágeno, con la particularidad de poseer un proceso de elaboración artesanal y de contar con envases de vidrio con el objetivo de no solo generar un impacto positivo en la sociedad, sino también en el medio ambiente. En tal sentido, tomando en consideración el contexto actual, se optó por el método de venta online de manera que sea más accesible su comercialización. De forma consecuente, se procedió a redefinir nuestro radio de atención para el primer año en base a nuestra capacidad operativa y cercanía / dirigiéndonos así, a diez distritos pertenecientes a Lima Metropolitana Moderna. En el transcurso de la investigación, se efectuaron encuestas para precisar el precio y tamaño de presentación, se consultó fuentes respaldadas para el sustento de los presupuestos y proyecciones exhibidas, se ejecutaron acciones de marketing para impulsar las ventas, entre otras actividades que nos permitieron preparar un ensayo acertado.

El presente estudio se desarrolló con el propósito de implementar una idea de negocio escalable, visionaria y atractiva; a raíz de esto, se realizó una investigación de mercado a fin de obedecer las tendencias y responder a las demandas insatisfechas. Los resultados del análisis señalaron que: las personas se mantienen en constante búsqueda de productos saludables y de fácil consumo, aprecian más los alimentos naturales que los procesados, prestan especial atención al valor nutricional de lo que ingieren y demuestran empatía de cara al medio ambiente. Ante esto, se consolidó la propuesta referida al lanzamiento de una bebida frutada 100% natural a base de colágeno, con la particularidad de poseer un proceso de elaboración artesanal y de contar con envases de vidrio con el objetivo de no solo generar un impacto positivo en la sociedad, sino también en el medio ambiente. En tal sentido, tomando en consideración el contexto actual, se optó por el método de venta online de manera que sea más accesible su comercialización. De forma consecuente, se procedió a redefinir nuestro radio de atención para el primer año en base a nuestra capacidad operativa y cercanía; dirigiéndonos así, a diez distritos pertenecientes a Lima Metropolitana Moderna. En el transcurso de la investigación, se efectuaron encuestas para precisar el precio y tamaño de presentación, se consultó fuentes respaldadas para el sustento de los presupuestos y proyecciones exhibidas, se ejecutaron acciones de marketing para impulsar las ventas, entre otras actividades que nos permitieron preparar un ensayo acertado. / The present study was developed with the purpose of implementing a scalable, visionary and attractive business idea; Following this, a market research was conducted to obey trends and respond to the demands. The results of the analysis indicated that: people are constantly searching for healthy and easy-to-eat products, they appreciate natural foods more than processed ones, they pay special attention to the nutritional value of what they eat and they show empathy towards the environment. Because of this, the proposal regarding the launch of a 100% natural collagen-based fruit drink was consolidated, with the particularity of having an artisanal manufacturing process and having glass containers with the aim of not only generating a positive impact on society, but also in the environment. In this sense, taking into account the current context, the online sales method was chosen so that its commercialization is more accessible. Consequently, we proceeded to redefine our service radius for the first year based on our operational capacity and proximity; addressing us to ten districts belonging to Modern Metropolitan Lima. In the course of the investigation, surveys were conducted to specify the price and size of the presentation, we consulted backed sources for the livelihood of the budgets and projections exhibited, marketing actions were carried out to boost sales, among other activities that allowed us to prepare a successful essay. / Trabajo de investigación

The use of 3D printing in biological applications is a new field of study given that 3D printing technology has become more available and user friendly. Possible uses include using existing 3D printing polymers to use in extracorporeal or in vitro devices, like Lab-on-a-Chip, and the development of new biologically derived materials to print cell-containing constructs. The latter concept is what is more commonly known as bioprinting. Our research had the goal of developing a bioprinting system including the printer, a bioink, and a feedback system for printing parameter optimization which could be done cheaply and within the reach of nearly any research lab. To make the bioprinter, we were able to take a popular plastic 3D printer and convert it to a bioprinter with 3D printed parts and the addition of a new motherboard. This came with great contribution from Carnegie Melon University. We were also able to improve upon the original design and, along with the new bioprinting capabilities, maintain the original capabilities of the plastic 3D printer. A new bioink was developed to work in coordination with this bioprinting system. Our lab has the luxury of having access to decellularized tissue, which provided a unique material to create a bioink which is derived from the extra-cellular matrix of porcine hearts. The final bioink protocol allows the users to make their own bioink, from easily obtainable tissue and determine their own concentration of the extra-cellular matrix/collagen within a range. Lastly, a feedback system was developed using a Raspberry Pi and camera module to provide real-time visual feedback of the bioprinting process which is otherwise very difficult to see and optimize parameters from. A protocol was developed to sequentially optimize the parameters for an open-source slicing software which governs the resolution of the bioprinter itself. In related research, the cytotoxicity and cell adherence properties of a printing resin for a microfluidic 3D printer were evaluated for use in Lab-on-a-Chip applications. The existing resin was tested and determined to be cytotoxic to cells and therefore not suitable for biological applications. We showed that a simple ethanol washing step and plasma treatment pulled the cytotoxic elements out of the polymer and modified the surface such that cells could attach and proliferate on the printed resin. Another printed resin was also tested which was determined to have no natural cytotoxicity, but the same plasma treatment was needed to allow for cell adherence.

The occurrence of a functional intracellular renin-angiotensin system (RAS) has emerged as a new paradigm. Recently, we and others demonstrated intracellular synthesis of ANG II in cardiac myocytes and vascular smooth muscle cells that was dramatically stimulated in high glucose conditions. Cardiac fibroblasts significantly contribute to diabetes-induced diastolic dysfunction. The objective of the present study was to determine the existence of the intracellular RAS in cardiac fibroblasts and its role in extracellular matrix deposition. Neonatal rat ventricular fibroblasts were serum starved and exposed to isoproterenol or high glucose in the absence or presence of candesartan, which was used to prevent receptor-mediated uptake of ANG II. Under these conditions, an increase in ANG II levels in the cell lysate represented intracellular synthesis. Both isoproterenol and high glucose significantly increased intracellular ANG II levels. Confocal microscopy revealed perinuclear and nuclear distribution of intracellular ANG II. Consistent with intracellular synthesis, Western analysis showed increased intracellular levels of renin following stimulation with isoproterenol and high glucose. ANG II synthesis was catalyzed by renin and angiotensin-converting enzyme (ACE), but not chymase, as determined using specific inhibitors. High glucose resulted in increased transforming growth factor-β and collagen-1 synthesis by cardiac fibroblasts that was partially inhibited by candesartan but completely prevented by renin and ACE inhibitors. In conclusion, cardiac fibroblasts contain a functional intracellular RAS that participates in extracellular matrix formation in high glucose conditions, an observation that may be helpful in developing an appropriate therapeutic strategy in diabetic conditions.

Introduction: The stabilization of dentinal collagen fibers against enzymatic degradation by the use of biocompatible cross-linker agents is of clinical importance for effective dentin bonding to surpass the test of time. Objective: The present study aims to evaluate and compare the effect of the application of two versions of a desensitizer solution to sound coronal dentin, on the microtensile bond strength (μTBS) of the resin-sound coronal dentin using 4th and 6th generation dentin bonding systems. Materials and Methods: Extracted human third molars were collected from an unidentified bank of teeth followed by IRB approval. A flat surface of all 12 teeth was prepared utilizing a water-cooled high-speed diamond disc, leaving an entire hard sound dentinal area for testing. Subsequently, according to the assigned group, specimens followed specific manufacturer’s instructions for application of dentin bonding systems: specimens were subdivided into 6 groups (n=20). Group 1 (G1) First positive control group. Specimens received an application of a 4th generation dentin bonding system (DBS). Group 2 (G2) Second positive control group. Specimens received an application of a 6th generation DBS. Group 3 (G3) Specimens were exposed to Gluma Desensitizer agent, blot-dried and followed by application of a 4th generation DBS. Group 4 (G4) Specimens were exposed to Gluma Desensitizer agent, blot-dried and followed by application of a 6th generation DBS. Group 5 (G5) Specimens were exposed to Gluma Desensitizer PowerGel agent, blot-dried and followed by application of a 4th generation DBS. Group 6 (G6) Specimens were be exposed to Gluma Desensitizer PowerGel agent, blot-dried and received an application of a 6th generation DBS. After application of the adhesive systems, all specimens were restored using a microhybrid resin composite. The root portion was sectioned 1mm below the CEJ, and discarded. All specimens were thermocycled at 5-55 Cº for 7000 cycles on distilled water. Then each restored tooth was sectioned perpendicular to the bonding interface into 1mm x 1mm x 8mm beams with a slow speed diamond wafering blade under thorough irrigation. Then specimens were subjected to μTBS testing at a crosshead speed of 1mm/min. Subsequently; specimens were subjected to fracture analysis and SEM evaluation of the different failure’s mode of the involved surfaces. Statistical analysis was performed by usingone- way ANOVA, two-way ANOVA and Fisher’s PLSD test (p<0.05). Results: For the first aim of the study and after obtaining the μTBS in MPa: Group G1: 15.50 ± 6.28, Group G2: 13.06 ± 11.53, Group G3: 19.20 ± 9.43, Group G4: 12.76 ± 4.61, Group G5: 14.38 ± 5.95, Group G6: 18.54 ± 9.49. Statistical analysis showed that there is no significant influence of variables on the μTBS (Welch ANOVA [F (5,114) =2.21, p=0.057]). Treatment with Gluma desensitizing agent and Gluma desensitizing PowerGel has no significant influence on the bond strength. For the second aim of the study and to analyze group differences for type of fracture data was first recoded into two groups: (1) Adhesive failure and (2) Cohesive failure. Group differences were analyzed by type of fracture using a Fisher’s exact test. No difference was found between the groups by type offracture (5, N = 120) = 8.62, p = 0.090 Conclusion: Within the limitations of this in vitro study it can be concluded that Gluma desensitizing agent and Gluma desensitizing PowerGel did not significantly affect the μTBS of both 4th and 6th generation bonding system using extracted human teeth.