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1.
J. venom. anim. toxins incl. trop. dis ; 30: e20230043, 2024. graf
Article Dans Anglais | LILACS, VETINDEX | ID: biblio-1534803

Résumé

Background: The bioactive peptides derived from snake venoms of the Viperidae family species have been promising as therapeutic candidates for neuroprotection due to their ability to prevent neuronal cell loss, injury, and death. Therefore, this study aimed to evaluate the cytoprotective effects of a synthetic proline-rich oligopeptide 7a (PRO-7a; <EDGPIPP) from Bothrops jararaca snake, on oxidative stress-induced toxicity in neuronal PC12 cells and astrocyte-like C6 cells. Methods: Both cells were pre-treated for four hours with different concentrations of PRO-7a, submitted to H2O2-induced damage for 20 h, and then the oxidative stress markers were analyzed. Also, two independent neuroprotective mechanisms were investigated: a) L-arginine metabolite generation via argininosuccinate synthetase (AsS) activity regulation to produce agmatine or polyamines with neuroprotective properties; b) M1 mAChR receptor subtype activation pathway to reduce oxidative stress and neuron injury. Results: PRO-7a was not cytoprotective in C6 cells, but potentiated the H2O2-induced damage to cell integrity at a concentration lower than 0.38 μM. However, PRO-7a at 1.56 µM, on the other hand, modified H2O2-induced toxicity in PC12 cells by restoring cell integrity, mitochondrial metabolism, ROS generation, and arginase indirect activity. The α-Methyl-DL-aspartic acid (MDLA) and L-NΩ-Nitroarginine methyl ester (L-Name), specific inhibitors of AsS and nitric oxide synthase (NOS), which catalyzes the synthesis of polyamines and NO from L-arginine, did not suppress PRO-7a-mediated cytoprotection against oxidative stress. It suggested that its mechanism is independent of the production of L-arginine metabolites with neuroprotective properties by increased AsS activity. On the other hand, the neuroprotective effect of PRO-7a was blocked in the presence of dicyclomine hydrochloride (DCH), an M1 mAChR antagonist. Conclusions: For the first time, this work provides evidence that PRO-7a-induced neuroprotection seems to be mediated through M1 mAChR activation in PC12 cells, which reduces oxidative stress independently of AsS activity and L-arginine bioavailability.(AU)


Sujets)
Oligopeptides/effets indésirables , Récepteur muscarinique/composition chimique , Venins de crotalidé/synthèse chimique , Proline , Stress oxydatif
2.
Rev. Asoc. Odontol. Argent ; 111(3): 1111212, sept.-dic. 2023. ilus, tab
Article Dans Espagnol | LILACS | ID: biblio-1554482

Résumé

Objetivo: Comparar dos procedimientos de soldadura convencionales empleando una aleación de Cr-Co, para co- nectar barras coladas seccionadas a ser fijadas sobre implantes. Materiales y métodos: A partir de un modelo maes- tro que representa un maxilar desdentado con cuatro implan- tes, se confeccionaron veinte (n=20) probetas seccionadas en tres partes. Se conformaron dos grupos, cada uno con diez (n=10) ejemplares. Una vez acondicionadas, fueron atornilla- das al modelo maestro. Su desajuste inicial se analizó utili- zando una lupa estereoscópica, con una cámara incorporada y un software. Las partes fueron soldadas empleando un pro- cedimiento diferente para cada grupo. Las correspondientes al Grupo I se invistieron en un block refractario a base de sílico-fosfato. Las del Grupo II se montaron en una estructu- ra metálica Clever Spider. El desajuste fue mensurado y los resultados procesados estadísticamente. El nivel de significa- ción fue establecido en p<0,05. Resultados: El Grupo I tuvo un desajuste inicial de 97,30±13,81µm y el Grupo II de 98,53±11,24µm. Luego de la soldadura, el Grupo I registró 98,53±17,17µm, 1,23µm mayor respecto al inicial. En el Grupo II se observó 103,13±17,61µm, 4,60µm por encima del original. Se analizaron mediante prue- ba t de Student; en ambos casos el resultado fue de p>0,05. Al comparar entre sí los grupos I y II, por medio de la prueba t y de comprobación no paramétrica de Mann-Whitney, se ob- servaron diferencias no significativas, p=0,41 y p=0,38 res- pectivamente (AU)


Aim: Compare two conventional welding procedures us- ing a Cr-Co alloy, to connect sectioned cast bars to be fixed on implants. Materials and methods: From a master model representing a toothless jaw with four implants, twenty (n=20) specimens sectioned into three parts were made. Two groups were formed, each with ten (n=10) specimens. Once conditioned, they were screwed to the master mod- el. Its initial mismatch was analyzed using a stereoscop- ic magnifier, with a built-in camera and a software. The parts were welded using a different procedure for each group. Those corresponding to Group I were invested in a refractory block based on silyl-phosphate. Those of Group II were mounted on a Clever Spider metal structure. The mismatch was measured, and the results processed statisti- cally. The level of significance was established at p<0.05. Results: Group I had an initial mismatch of 97.30 ±13.81µm, and Group II of 98.53±11.24µm. After welding, Group I registered 98.53±17.17µm, 1.23µm higher than the initial one. In Group II, 103.13±17.61µm was observed, 4.60µm above the original. They were analyzed using Stu- dent's t test; in both cases the result was p>0.05. When com- paring groups I and II, using the t-test and the Mann-Whitney nonparametric verification, non-significant differences were observed, p=0.41 and p=0.38 respectively. Conclusions: Under the conditions of this study, it was ob- served that the two welding methods analyzed were reliable for joining metallic superstructures without affecting their final fit (AU)


Sujets)
Soudage dentaire , Rétention de prothèse dentaire/méthodes , Essayage de prothèse/méthodes , Prothèse dentaire implanto-portée/méthodes , Interprétation statistique de données , Alliages de chrome/synthèse chimique , Overdenture
3.
Actual. osteol ; 19(2): 128-143, sept. 2023. ilus, tab
Article Dans Espagnol | LILACS, UNISALUD, BINACIS | ID: biblio-1523882

Résumé

El presente trabajo muestra la obtención de un material a partir de un polímero sintético (TerP) y otro natural, mediante entrecruzamiento físico y su caracterización fisicoquímica y biológica, con el fin de emplearlos para regeneración de tejido óseo. Las membranas fueron obtenidas por la técnica de evaporación del solvente y caracterizadas por espectroscopia FTIR, ensayos de hinchamiento, medidas de ángulo de contacto y microscopia electrónica de barrido (SEM). Se encontró que la compatibilidad entre los polímeros que la constituyen es estable a pH fisiológico y que, al incorporar mayor cantidad del TerP a la matriz, esta se vuelve más hidrofóbica y porosa. Además, teniendo en cuenta la aplicación prevista para dichos materiales, se realizaron estudios de biocompatibilidad y citotoxicidad con células progenitoras de médula ósea (CPMO) y células RAW264.7, respectivamente. Se evaluó la proliferación celular, la producción y liberación de óxido nítrico (NO) al medio de cultivo durante 24 y 48 horas y la expresión de citoquinas proinflamatorias IL-1ß y TNF-α de las células crecidas sobre los biomateriales variando la cantidad del polímero sintético. Se encontró mayor proliferación celular y menor producción de NO sobre las matrices que contienen menos proporción del TerP, además de poseer una mejor biocompatibilidad. Los resultados de este estudio muestran que el terpolímero obtenido y su combinación con un polímero natural es una estrategia muy interesante para obtener un biomaterial con posibles aplicaciones en medicina regenerativa y que podría extenderse a otros sistemas estructuralmente relacionados. (AU)


In the present work, the preparation of a biomaterial from a synthetic terpolymer (TerP) and a natural polymer, physically crosslinked, is shown. In order to evaluate the new material for bone tissue regeneration, physicochemical and biological characterizations were performed. The membranes were obtained by solvent casting and characterized using FTIR spectroscopy, swelling tests, contact angle measurements, and scanning electron microscopy (SEM). It was found that the compatibility between the polymers is stable at physiological pH and the incorporation of a higher amount of TerP into the matrix increases hydrophobicity and porosity.Furthermore, considering the intended application of these materials, studies of biocompatibility and cytotoxicity were conducted with Bone Marrow Progenitor Cells (BMPCs) and RAW264.7 cells, respectively. Cell proliferation, NO production and release into the culture medium for 24 and 48 hours, and proinflammatory cytokine expression of IL-1ß and TNF-α from cells grown on the biomaterials while varying the amount of the synthetic polymer were evaluated. Greater cell proliferation and lower NO production were found on matrices containing a lower proportion of TerP, in addition to better biocompatibility. The results of this study demonstrate that the obtained terpolymer and its combination with a natural polymer is a highly interesting strategy for biomaterial preparation with potential applications in regenerative medicine. This approach could be extended to other structurally related systems. (AU)


Sujets)
Animaux , Rats , Ostéogenèse , Polymères/composition chimique , Matériaux biocompatibles/synthèse chimique , Os et tissu osseux/composition chimique , Régénération osseuse , Chitosane/composition chimique , Polymères/toxicité , Matériaux biocompatibles/toxicité , Test de matériaux , Différenciation cellulaire , Chromatographie sur gel , Spectroscopie infrarouge à transformée de Fourier , Techniques de culture cellulaire , Résonance magnétique nucléaire biomoléculaire , Chitosane/toxicité
4.
Braz. j. biol ; 83: 1-9, 2023. ilus, tab, graf
Article Dans Anglais | LILACS, VETINDEX | ID: biblio-1468915

Résumé

Many soil microorganisms' i.e., bacteria and fungi produce secondary metabolites called antibiotics. These are used for the treatment of some of the bacterial, fungal and protozoal diseases of humans. There is a need for isolation of a broad spectrum of antibiotics from microorganisms due to the emergence of antibiotic resistance. In the present study two antibiotic producing bacteria Klebsiella pneumoniae and Bacillus cereus were isolated from pharmaceutical and poultry feed industry of Hattar, Haripur Pakistan. Total 10 waste samples were collected from different industries (Marble, Ghee, Soap, Mineral, Steel, Poultry Feed, Pharmaceutical, Qarshi, Cosmetic and Glass). Thirty-three bacterial strains were isolated from industrial wastes of these ten different industries. Fourteen out of thirty-three bacterial strains exhibited antimicrobial activities against at least one of the test microbes considered in this study including Escherchia coli, Staphylococcus aureus and Salmonella typhi. The bacteria were isolated by standard serial dilution spread plate technique. Morphological characterization of the isolates was done by Gram staining. Nine bacterial isolates out of fourteen were initially identified as B. cereus and five as K. pneumoniae through biochemical characterization. The antibacterial activities were tested by well diffusion method. Maximum number of antibiotic producing bacteria were isolated from pharmaceutical and poultry feed industry based on the results of primary screening, the most potential isolates S9, S19, S20, S22 and S23 were selected for secondary screening. The maximum activity against E. coli and S. aureus was recorded by bacterial isolate S19 i.e zones of inhibition of 6.5mm and 9mm while S20 showed 7.5mm and 6mm zones respectively. Molecular identification was carried out on the basis of 16S rRNA sequence [...].


Muitos microrganismos do solo, ou seja, bactérias e fungos produzem metabólitos secundários chamados antibióticos. Eles são usados para tratamento de algumas doenças bacterianas, fúngicas e protozoárias em humanos. Há necessidade de isolamento de um amplo espectro de antibióticos de microrganismos devido ao surgimento de resistência aos antibióticos. No presente estudo, duas bactérias produtoras de antibióticos, Klebsiella pneumoniae e Bacillus cereus, foram isoladas da indústria farmacêutica e de ração avícola de Hattar, Haripur, Paquistão. Um total de 10 amostras de resíduos foi coletado de diferentes indústrias (mármore, ghee, sabão, mineral, aço, ração para aves, farmacêutica, Qarshi, cosmética e vidro). Trinta e três cepas bacterianas foram isoladas de resíduos industriais dessas dez diferentes indústrias. Quatorze das 33 cepas bacterianas exibiram atividades antimicrobianas contra pelo menos um dos micróbios de teste considerados neste estudo, incluindo Escherchia coli, Staphylococcus aureus e Salmonella typhi. As bactérias foram isoladas pela técnica de placa de diluição em série padrão. A caracterização morfológica dos isolados foi feita por coloração de gram. Nove isolados bacterianos de 14 foram inicialmente identificados como B. cereus e cinco como K. pneumoniae por meio de caracterização bioquímica. As atividades antibacterianas foram testadas pelo método de difusão em poço. O número máximo de bactérias produtoras de antibióticos foi isolado da indústria farmacêutica e de ração avícola com base nos resultados da triagem primária, os isolados mais potenciais S9, S19, S20, S22 e S23 foram selecionados para a triagem secundária. A atividade máxima contra E. coli e S. aureus foi registrada pelo isolado bacteriano S19, ou seja, zonas de inibição de 6,5 mm e 9 mm, enquanto S20 mostrou zonas de 7,5 mm e 6 mm, respectivamente. A identificação molecular foi realizada com base na análise da sequência 16S [...].


Sujets)
Antibactériens/synthèse chimique , Bacillus cereus/isolement et purification , Klebsiella/isolement et purification , Aliment pour animaux/analyse , Déchets industriels/analyse
5.
Braz. j. oral sci ; 22: e231137, Jan.-Dec. 2023. ilus
Article Dans Anglais | LILACS, BBO | ID: biblio-1523140

Résumé

The purpose of this in vitro study was to analyze the influence of nicotine on the extracellular polysaccharides in Fusobacterium nucleatum biofilm. Methods: F. nucleatum (ATCC 10953) biofilms supplemented with different concentrations of nicotine (0, 0.5, 1, 2, 4, and 8 mg/mL) were grown in two different BHI broth conditions [no sucrose and 1% sucrose]. Extracellular polysaccharides assay, pH measurements, and a spectrophotometric assay were performed. Data were submitted for ANOVA and Tukey honestly significant difference analyses (HSD) tests (α =.05). Results: Extracellular polysaccharides synthesis was influenced by an interaction between nicotine concentrations and growth medium solution containing sucrose (P<.05). The pH values declined in the sucrose-exposed biofilm were greater than in the group exposed only to nicotine (P<.05). The biofilm exposed to sucrose and nicotine had a higher total biofilm growth (P<.05) than the nicotine-treated biofilm without sucrose. Conclusions: Regardless of sucrose exposure, biofilms exposed to different nicotine concentrations influenced the amount of extracellular polysaccharides


Sujets)
Humains , Polyosides bactériens/synthèse chimique , Fusobacterium nucleatum/croissance et développement , Biofilms/croissance et développement , Nicotine/pharmacologie , Maladies parodontales/microbiologie , Spectrophotométrie , Saccharose/administration et posologie , Milieux de culture , Caries dentaires/microbiologie , Nicotine/administration et posologie
6.
Braz. J. Pharm. Sci. (Online) ; 59: e21508, 2023. tab, graf
Article Dans Anglais | LILACS | ID: biblio-1439512

Résumé

Abstract Ellagic acid (EA) is a phenolic biomolecule. For its biosynthesis, a source of ellagitannins is required, such as strawberries and yeasts, as precursors of the tannase and ß-glucosidase enzymes responsible for hydrolysis of ellagitannins. Two experimental mixture designs were applied., varying the yeast concentration and the number of ellagitannins in the culture medium, evaluating the enzymatic activity and ellagic acid biosynthesis. Aiming to find the optimal compositions of the non-conventional yeasts assessed in the research to biosynthesize ellagic acid feasibly and efficiently using a response surface performing the statistical analysis in the StatGraphics® program for obtaining a higher yield and optimizing the ellagic acid synthesis process, the results indicate that the strains Candida parapsilosis ITM LB33 and Debaryomyces hansenii ISA 1510 have a positive effect on the synthesis of ellagic acid, since as its concentration increases in the mixture the concentration of ellagic acid in the medium also increases; on the other hand, the addition of Candida utilis ITM LB02 causes a negative effect, resulting in the compositions of 0.516876, 0.483124 and 2.58687E-9 respectively, for a treatment under the same conditions, an optimal value of ellagic acid production would be obtained. With an approximate value of 7.33036 mg/mL


Sujets)
Levures/classification , Bioréacteurs/classification , Acide ellagique/synthèse chimique , Optimisation du Processus , Debaromyces/classification , Candida parapsilosis/classification
7.
Actual. osteol ; 18(2): 60-74, oct. 2022. graf, ilus, tab
Article Dans Espagnol | LILACS, UNISALUD, BINACIS | ID: biblio-1437640

Résumé

Introducción: Los GOS son prebióticos naturales presentes en la leche materna que pue-den obtenerse enzimáticamente a partir de la lactosa de leche de vaca durante la fabricación de yogur. El producto lácteo resultante será reducido en lactosa y contendrá prebióticos y bacterias potencialmente probióticas. Sin embargo, mantendrá la baja relación Ca/Pi que aporta la leche de vaca, lo que podría alterar el remodelamiento óseo y la mineralización. Objetivo: comparar si un yogur reducido en lactosa que contiene GOS (YE) ofrece ventajas adicionales respecto de un yogur regular sin GOS (YR) sobre las absorciones (Abs) de Ca y Pi, retención y calidad ósea durante el crecimiento normal. Al destete, ratas machos fueron divididas en 3 grupos alimentados con AIN ́93-G (C), YE o YR durante 28 días. Resultados: YE mostró el mayor aumento de lactobacilos fecales; producción de ácidos grasos de cadena corta especialmente p, profundidad de las criptas colónicas y menor pH cecal. El %AbsCa y %AbsPi aumentó en el siguiente órden: YE> YR> C (p < 0,05). El contenido de Ca y Pi en fémur, la densidad y contenido mineral óseos y los parámetros biomecánicos fueron similares en YE y C, mientras que YR mostró valores significativa-mente menores (p < 0,05). Conclusiones: YE aumentó las Abs y biodisponibilidad de minerales, alcanzando la retención y calidad ósea de C. El aumento en las Abs observado en YR no logró obtener la retención y calidad ósea de C. Conclusión: YE habría contrarrestado el efecto negativo del mayor aporte de Pi de la leche de vaca y sería una buena estrategia para lograr el pico de masa ósea y calidad del hueso adecuados, especialmente en individuos intolerantes a la lactosa. (AU)


Breast milk contains an optimal calcium/phosphate (Ca/Pi) ratio and GOS. These natural prebiotics can be enzymatically produced via cow's milk lactose inyogurt manufacture. This milk product is low in lactose and contains prebiotics and potentially probiotic bacteria but maintains a low Ca/Pi ratio that could alter bone remodeling and mineralization. We evaluated if a lactose-reduced yogurt containing GOS (YE) offers additional advantages over regular yogurt without GOS (YR) on Ca and Pi absorption (Abs), bone retention and quality during normal growth. Weaning male rats were divided into 3 groups fed AIN'93-G (C), YE or YR for 28 days. Results: YE showed the highest increase in fecal lactobacilli; short-chain fatty acids production, especially propionate and butyrate; intestine crypt depth, and the lowest cecal pH. AbsCa% and AbsPi% increased in this order: YE> YR> C (p <0.05). Ca and Pi content in femur, bone density and mineral content, and biomechanical parameters were similar in YE and C, while YR showed the significantly lowest value (p < 0.05). Conclusions: YE increased mineral Abs reaching the retention and bone quality of C. Although YR increased Abs, bone retention and quality did not achieve C values. Seemingly, YE compensated for the negative effect of the higher Pi supply and would be a good strategy to achieve adequate peak bone mass and bone quality, especially in lactose intolerant individuals. (AU)


Sujets)
Animaux , Rats , Oligosaccharides/métabolisme , Ostéogenèse/physiologie , Calcium alimentaire/pharmacocinétique , Phosphore alimentaire/pharmacocinétique , Absorption intestinale/physiologie , Lactose/métabolisme , Magnésium/pharmacocinétique , Tibia/anatomie et histologie , Yaourt/analyse , Calcium alimentaire/métabolisme , Absorptiométrie photonique , Densité osseuse , Interprétation statistique de données , Phosphore alimentaire/métabolisme , beta-Galactosidase/synthèse chimique , Rat Wistar , Lactobacillus delbrueckii/isolement et purification , Fémur/anatomie et histologie , Gros intestin/anatomie et histologie , Magnésium/métabolisme , Valeur nutritive
8.
J. oral res. (Impresa) ; 11(4): 1-12, jul. 21, 2022. ilus, tab
Article Dans Anglais | LILACS | ID: biblio-1427279

Résumé

Aim: To investigate the precipitate formed from the interaction between 2% lidocaine hydrochloride with adrenaline (LA) with 2.5% sodium hypochlorite (NaOCl) and 0.2% chitosan nanoparticles on root canal dentin, using scanning electron microscopy (SEM). Material and Methods: Sixty mandibular premolars were decoronated, and the root length standardised. The specimens were randomly distributed into the following groups: Group 1 (control): 2% LA mixed with sterile water without root canal instrumentation, Group 2: 2% LA with 2.5% NaOCl in water without root canal instrumentation, and Group 3: 2% LA with 0.2% chitosan nanoparticles in water without root canal instrumentation. Teeth specimens were split and subjected to SEM analysis at cervical, middle, and apical root thirds. On observing precipitate formation in Group 2, 10 premolars were decoronated and treated with 2% LA and 2.5% NaOCl and subjected to root canal instrumentation. Results: Group 1 and Group 3 showed patent dentinal tubules and no precipitate formation. Group 2 showed precipitate blocking dentinal tubules in all the three sections, and the precipitate could not be removed completely after cleaning and shaping. Conclusion: NaOCl forms an insoluble precipitate on interaction with local anaesthetic solution that cannot be removed after chemo-mechanical preparation. Chitosan nanoparticles do not form any such precipitate and show patent dentinal tubules. Hence, chitosan can be used as a flushing irrigant.


Objetivo: Investigar el precipitado formado a partir de la interacción entre el clorhidrato de lidocaína al 2% con adrenalina (LA), el hipoclorito de sodio al 2,5% (NaOCl) y nanopartículas de quitosano al 0,2% en la dentina del conducto radicular, mediante microscopía electrónica de barrido (SEM). Material y Métodos: Se decoraron 60 premolares mandibulares y se estandarizó la longitud de la raíz. Los especímenes se distribuyeron aleatoriamente en los siguientes grupos: Grupo 1 (control): 2% la que fue mezclado con agua estéril sin instrumentación del conducto radicular, Grupo 2: 2% LA con 2,5% de NaOCl sin instrumentación del conducto radicular y Grupo 3: 2 % LA con 0,2% de nanopartículas de quitosano sin instrumentación del conducto radicular. Las muestras de dientes se dividieron y se sometieron a análisis SEM en los tercios radiculares cervical, medio y apical. Al observar la formación de precipitado en el Grupo 2, 10 premolares fueron decorados y tratados con LA al 2% y NaOCl al 2,5% y sometidos a instrumentación de conductos radiculares. Resultado: El Grupo 1 y el Grupo 3 mostraron túbulos dentinarios permeables y sin formación de precipitados. El grupo 2 mostró precipitado que bloqueaba los túbulos dentinarios en las tres secciones, y el precipitado no se pudo eliminar por completo después de limpieza y conformación. Conclusión: el NaOCl forma un precipitado insoluble al interactuar con la solución anestésica local que no se puede eliminar después de la preparación quimiomecánica. Las nanopartículas de quitosano no forman ningún precipitado de este tipo y muestran túbulos dentinarios permeables. Por lo tanto, el quitosano se puede utilizar como irrigante para el lavado.


Sujets)
Humains , Liquides d'irrigation endocanalaire/synthèse chimique , Hypochlorite de sodium/synthèse chimique , Chitosane/synthèse chimique , Lidocaïne/synthèse chimique , Prémolaire , Techniques in vitro , Boue dentinaire
9.
J. oral res. (Impresa) ; 11(1): 1-13, may. 11, 2022. ilus
Article Dans Anglais | LILACS | ID: biblio-1398893

Résumé

Introduction: This study aimed to prepare a new root repair material including Portland cement, bismuth oxide, and nano-hydroxyapatite and analyze its physicochemical properties and its effects on the proliferation and differentiation of human dental pulp stem cells (hDPSCs). Material and Methods: Bismuth oxide as a radiopaque component and nano-hydroxyapatite particles were added to white Portland cement at 20% and 5% weight ratio, respectively. Characterization of the prepared cement was done using conventional methods. To examine the bioactivity of this new material, atomic absorption spectroscopy (AAS) was used for the investigation of the rate of calcium ions dissolution in simulated body fluid media. The viability of hDPSCs was assessed by an MTT assay after 1, 3 and 7 days. The odontogenic potential of this substance was evaluated by measuring alkaline phosphatase activity and alizarin red S staining. Results: Based on the bioactivity results, the cement presented high bio-activity, corroborating sufficiently with the calcium release patterns. The cell viability was significantly increased in new root repair material containing hydroxyapatite nanoparticles after 3 and 7 days (p<0.05). Conclusion: Moreover, alkaline phosphatase activity increased over 7 days in all experimental groups. The new cement containing nano-hydroxyapatite particles could be a good root repair material.


Objetivo: Este estudio tuvo como objetivo preparar un nuevo material de reparación de raíces que incluye cemento Portland, óxido de bismuto y nano-hidroxiapatita y analizar sus propiedades fisicoquímicas y sus efectos sobre la proliferación y diferenciación de células madre de pulpa dental humana. Material y Métodos: El óxido de bismuto como compo-nente radiopaco y las partículas de nano-hidroxiapatita se agregaron al cemento Portland blanco en una proporción en peso del 20 % y el 5 %, respectivamente. La caracterización del cemento preparado se realizó utilizando métodos con-vencionales. Para examinar la bioactividad de este nuevo material, se utilizó la espectroscopia de absorción atómica para investigar la velocidad de disolución de los iones de calcio en medio fluido corporal simulado. La viabilidad de las células madre de pulpa dental humana se evaluó mediante un ensayo MTT después de 1, 3 y 7 días. El potencial odontogénico de esta sustancia se evaluó midiendo la actividad de la fosfatasa alcalina y la tinción con rojo de alizarina S.Resultados: Con base en los resultados de bioactividad, el cemento presentó alta bioactividad, corroborando suficientemente con los patrones de liberación de calcio. La viabilidad celular aumentó significativamente en el nuevo material de reparación de raíces que contenía nanopartículas de hidroxiapatita después de 3 y 7 días (p<0,05). Conclusión: Además, la actividad de la fosfatasa alcalina aumentó durante 7 días en todos los grupos experimentales. El nuevo cemento que contiene partículas de nanohidroxiapatita podría ser un buen material de reparación radicular.


Sujets)
Humains , Bismuthum Oxydatum , Silicates/synthèse chimique , Durapatite/synthèse chimique , Cément dentaire/composition chimique , Produits d'obturation des canaux radiculaires , Cellules souches , Pulpe dentaire , Nanoparticules
10.
Biomedical and Environmental Sciences ; (12): 215-224, 2022.
Article Dans Anglais | WPRIM | ID: wpr-927655

Résumé

Objective@#To develop effective alternatives to natural enzymes, it is crucial to develop nanozymes that are economical, resource efficient, and environmentally conscious. Carbon nanomaterials that have enzyme-like activities have been extensively developed as substitutes for traditional enzymes.@*Methods@#Carbide-derived carbons (CDCs) were directly synthesized via a one-step electrochemical method from a MAX precursor using an ammonium bifluoride electrolyte at ambient conditions. The CDCs were characterized by systematic techniques.@*Results@#CDCs showed bienzyme-like activities similar to that of peroxidase and superoxide dismutase. We systematically studied the dependence of CDC enzyme-like activity on different electrolytes and electrolysis times to confirm activity dependence on CDC content. Additionally, the synthesis mechanism and CDC applicability were elaborated and demonstrated, respectively.@*Conclusion@#The demonstrated synthesis strategy eliminates tedious intercalation and delamination centrifugation steps and avoids using high concentrations of HF, high temperatures, and halogen gases. This study paves the way for designing two-dimensional material-based nanocatalysts for nanoenzyme and other applications.


Sujets)
Humains , Composés d'ammonium/synthèse chimique , Carbone/composition chimique , Techniques électrochimiques , Enzymes , Fluorures/synthèse chimique , Nanostructures , Oxydoréduction
11.
Braz. J. Pharm. Sci. (Online) ; 58: e19494, 2022. tab, graf
Article Dans Anglais | LILACS | ID: biblio-1384024

Résumé

Abstract The aim of this paper is to study the chemical composition of alkaloids present in Haloxylon scoparium Pomel extracts and to evaluate their antioxidant capacity. The alkaloids were isolated from two parts of Haloxylon scoparium plant by two extraction protocols. and The quantitative study made it possible to propose the best protocol for the extraction of the alkaloids. Moreover, GC-MS analysis of alkaloid extracts allowed us to determine their chemical composition. Haloxylon scoparium contains four types of alkaloids: tetraisoquinolines, phenylethylamines, tryptolines and tryptamines. The main compounds are the tetraisoquinolines type, the predominant product of which was N-methylsalsoline. These compounds present a great interest for the researchers due to their various pharmacological and biological activities. The antioxidant effect of the different plant extracts was studied by two methods: the ferric reducing antioxidant power (FRAP) and 1,1-diphenyl-2-picryl hydrazyl free radical (DPPH·) scavenging tests. The results show that extracts of root part are more active than those from aerial part; the acetone/water extract is the most powerful. The interesting results obtained in this study will be supplemented by other analyses and biological tests in order to better valorize this plant.


Sujets)
Amaranthaceae/anatomie et histologie , Alcaloïdes/synthèse chimique , Maroc/ethnologie , Antioxydants/analyse , Extraits de plantes/analyse , Redistribution de fluorescence après photoblanchiment/méthodes
12.
Braz. J. Pharm. Sci. (Online) ; 58: e191120, 2022. tab, graf
Article Dans Anglais | LILACS | ID: biblio-1394048

Résumé

Abstract The aim of the current study was to assess the physicochemical characteristics and wound healing activity of chitosan-polyvinyl alcohol (PVA) crosslinked hydrogel containing recombinant human epidermal growth factor (rh-EGF) or recombinant mouse epidermal growth factor (rm-EGF). The hydrogels were prepared and analyses were made of the morphological properties, viscosity, water absorption capacity, mechanical and bio-adhesive properties. The viscosity of the formulations varied between 14.400 - 48.500 cPs, with the greatest viscosity values determined in K2 formulation. F2 formulation showed the highest water absorption capacity. According to the studies of the mechanical properties, H2 formulation (0.153±0.018 N.mm) showed the greatest adhesiveness and E2 (0.245±0.001 mj/cm2) formulation, the highest bio-adhesion values. Hydrogels were cytocompatible considering in vitro cell viability values of over 76% on human keratinocyte cells (HaCaT, CVCL-0038) and of over 84% on human fibroblast cells (NIH 3T3, CRL-1658) used as a model cell line. According to the BrdU cell proliferation results, B1 (197.82±2.48%) formulation showed the greatest NIH 3T3 and C1 (167.43±5.89%) formulation exhibited the highest HaCaT cell proliferation ability. In addition, the scratch closure assay was performed to assess the wound healing efficiency of formulation and the results obtained in the study showed that F2 formulation including PEGylated rh-EGF had a highly effective role.


Sujets)
Cicatrisation de plaie , Hydrogels/analyse , Chitosane/synthèse chimique , Facteur de croissance épidermique , Poly(alcool vinylique)/pharmacologie , Plaies et blessures/classification , Techniques in vitro/méthodes , Techniques de culture cellulaire/méthodes , Prolifération cellulaire/génétique , Absorption
13.
Braz. J. Pharm. Sci. (Online) ; 58: e191142, 2022. tab, graf
Article Dans Anglais | LILACS | ID: biblio-1394056

Résumé

A series of N-(benzoylphenyl)-carboxamide derivatives (2a, 2b, 3a, 3b, 4a, 4b, 5a, 5b, 6a and 6b) was prepared with good yields by reacting the corresponding carbonyl chlorides with aminobenzophenones at room temperature. This was followed by evaluating the hypotriglyceridemic and hypocholesterolemic effects of 3b, 5a and 5b. Triton WR-1339 (300 mg/kg) was intraperitoneally administered to overnight-fasted rats to induce hyperlipidemia. Rats were divided into six groups: control, hyperlipidemic, hyperlipidemic plus compounds 3b, 5a and 5b and hyperlipidemic plus bezafibrate. Results showed that after 18 h of treatment at a dose of 15 mg/kg body weight of each of the test compounds, the elevated plasma levels of triglycerides (TG) and total cholesterol (TC) were significantly lowered by compounds 5b and 3b (p < 0.001) and by 5a (p < 0.0001), compared to the hyperlipidemic control group. Compounds 3b and 5a significantly increased levels of high-density lipoprotein cholesterol (HDL-C) by 58 and 71%, respectively. In addition, compounds 3b and 5a caused significant reduction (p < 0.0001) of low-density lipoprotein cholesterol (LDL-C) levels compared to the control group. These results suggest a promising potential for compounds 3b, 5a and 5b as lipid-lowering agents, which may contribute to reducing the risk of atherosclerosis and cardiovascular disease


Sujets)
Animaux , Mâle , Rats , Pyridines/pharmacologie , Hyperlipidémies/induit chimiquement , Lipides/sang , Hypolipémiants/pharmacologie , Polyéthylène glycols , Pyridines/synthèse chimique , Triglycéride/sang , Cholestérol/sang , Rat Wistar , Modèles animaux de maladie humaine , Lipoprotéines HDL/effets des médicaments et des substances chimiques , Lipoprotéines LDL/effets des médicaments et des substances chimiques , Hypolipémiants/synthèse chimique
14.
Electron. j. biotechnol ; 50: 23-28, Mar. 2021. graf, ilus
Article Dans Anglais | LILACS | ID: biblio-1292311

Résumé

BACKGROUND: H2S is proved to be functioning as a signaling molecule in an array of physiological processes in the plant and animal kingdom. However, the H2S synthesis pathway and the responses to cold conditions remain unclear in postharvest mushroom. RESULTS: The biosynthesis of H2S in the Agaricus bisporus mushroom tissues exhibited an increasing tendency during postharvest storage and was significantly triggered by cold treatment. The cystathionine clyase (AbCSE) and cystathionine b-synthase (AbCBS) genes were cloned and proved responsible for H2S biosynthesis. Furthermore, transcriptional and posttranscriptional regulation of AbCSE and AbCBS were crucial for the enzyme activities and subsequent H2S levels. However, the AbMST was not involved in this process. Moreover, the AbCSE and AbCBS genes displayed low identity to the characterized genes, but typical catalytic domains, activity sites, subunit interface sites, and cofactor binding sites were conserved in the respective protein sequences, as revealed by molecular modeling and docking study. The potential transcription factors responsible for the H2S biosynthesis in cold conditions were also provided. CONCLUSIONS: The H2S biosynthetic pathway in postharvest mushroom was unique and distinct to that of other horticultural products.


Sujets)
Agaricus/composition chimique , Cystathionine beta-synthase/métabolisme , Cystathionine gamma-lyase/métabolisme , Sulfure d'hydrogène/synthèse chimique , Production végétale , Agaricus campestris , Basse température , Stockage des aliments
15.
Braz. arch. biol. technol ; 64: e21190750, 2021. tab, graf
Article Dans Anglais | LILACS | ID: biblio-1249207

Résumé

Abstract In this paper, the antibacterial activity of triazole functionalized cyclodextrin (CD.Click) and cyclodextrin-triazole-titanium based nanocomposite (CD.COM) was evaluated. The results indicated that CD.Click and CD.COM perform a wide range of antibacterial activity against both gram positive (Staphylococcus aureus and Bacillus subtilis) and gram negative (Escherichia coli and Pseudomonas aeruginosa) bacteria. The cytotoxic effect of CD.COM was investigated in vitro on cancerous cell lines (cervical cancer, breast carcinoma and sarcoma osteogenic) and fibroblast cells by MTT assay. The cell viability evaluation confirmed that the growth of cancerous cells is inhibited in a dose and time dependent way without any significant effect on the normal fibroblast cells.


Sujets)
Triazoles/synthèse chimique , Cyclodextrines bêta/synthèse chimique , Techniques in vitro/instrumentation , Antibiotiques antinéoplasiques
16.
Cienc. tecnol. salud ; 8(1)2021. il 27 c
Article Dans Espagnol | LILACS, DIGIUSAC, LIGCSA | ID: biblio-1352956

Résumé

Polymeric membrane technologies demand the synthesis of new polymers to enhance their equilibrium, thermal, and transport properties. Therefore, the focus of this investigation was the evaluation of the equilibrium and thermal properties of a sulfonated fluoroblock copolymer blend membrane composed of sulfonated poly(styre-ne-isobutylene-styrene) (SIBS SO3H) and a novel sulfonated fluoroblock copolymer composed of poly(4-fluo-rostyrene) (P4FS), poly(styrene) (PS) and poly(isobutylene) (PIB). The fluoroblock copolymer was synthesized using Atom Transfer Radical Polymerization (ATRP) and cationic polymerization. First, the molecular weight and the thermal stability of the block copolymer were determined using Gel Permeation Chromatography (GPC) and Thermogravimetric Analysis (TGA). Second, the chemical composition was monitored utilizing Fourier Transform Infrared spectroscopy (FTIR) and Nuclear Magnetic Resonance (NMR) spectroscopy. The molecular weight of P4FS-b-PS was Mn ~ 36,100; this value increased 8% after the cationic polymerization. The equilibrium properties of the membrane were evaluated using the water uptake and Ion-Exchange Capacity. The degradation behavior and the thermal transitions were determined using TGA and Differential Scanning Calorimetry (DSC), respectively. This newly membrane exhibited water uptake higher than 608% related to the improvement of 36% in the ion-exchange capacity and the increment of 25.31% and 25.24% in the energy required to produce the thermal transitions induced by the addition of the sulfonated fluoroblock copolymer.


La tecnología de membranas poliméricas requiere de la síntesis de nuevos polímeros que mejoren sus propiedades de equilibrio, térmicas y de transporte. Esta investigación tuvo como objetivo determinar las pro-piedades de equilibrio y térmicas de una membrana compuesta de poli(estireno-isobutileno-estireno) sulfonado (SIBS SO3H) y un fluoropolímero en bloque sulfonado compuesto de poli(4-fluorostireno) (P4FS), poli(estireno) (PS) y poli(isobutileno) (PIB). El fluoropolímero en bloque se sintetizó utilizando la técnica de polimerización radical por transferencia atómica (ATRP por sus siglas en inglés) y polimerización catiónica. El peso molecular y la estabilidad térmica del fluoropolímero en bloque fueron determinadas por medio de Cromatografía de Permeación en Gel (GPC) y un análisis termogravimétrico (TGA). La composición química se monitorizó utilizando espectroscopía infrarroja por transformada de Fourier (FTIR) y espectroscopía de Resonancia Magnética Nuclear (RMN). El peso molecular de P4FS-b-PS fue Mn ~ 36,100; este valor aumentó un 8% después de la polimerización catiónica. Las propiedades de equilibrio de la membrana fueron evaluadas por medio de la absorción de agua y la capacidad de intercambio iónico. El comportamiento de degradación y las transiciones térmicas se determinaron utilizando TGA y Calorimetría Diferencial de Barrido (DSC). Esta nueva membrana exhibió una absorción de agua mayor del 608% relacionada con la mejora del 36% en la capacidad de intercambio iónico y el incremento en 25.31% y 25.24% en la energía requerida para producir las transiciones termales inducidas por la adición del fluoropolímero sulfonado en bloque.


Sujets)
Polymères/composition chimique , Membrane artificielle , Polymères/synthèse chimique , Polystyrènes/composition chimique , Polymérisation , Absorption physico-chimique , Échange ionique , Masse moléculaire
17.
Electron. j. biotechnol ; 47: 10-16, sept. 2020. graf, tab
Article Dans Anglais | LILACS | ID: biblio-1224608

Résumé

BACKGROUND: Liquid wax esters are widely used in cosmetic as well as pharmaceutical and other industries. The demand of organic and natural products is increasing nowadays. Coconut oil contains benefit fatty acids and has been mainly used for oil-based and moisturizer products. Liquid wax esters from coconut oil and unsaturated fatty alcohol can be synthesized by enzymatic reaction; and it is interesting for using as an alternative natural ingredient in these industries. RESULTS: Optimal condition for coconut oil based wax ester synthesis by immobilized lipase EQ3 was 10 U of enzyme, temperature at 30°C and molar ratio of coconut oil to oleyl alcohol at 1:3 (mol/mol) (0.33X) dissolved in isooctane for 12 h, while for Lipozyme RM IM optimal condition was 10 U of enzyme, temperature at 45°C and oil/alcohol molar ratio at 1:3 (0.33X) dissolved in isooctane for 3 h. Percentage of wax esters synthesized by both lipases reached more than 88%. Both immobilized lipases catalyzed high yield of wax esters within the 2nd batch; after that, the immobilized lipases showed reduced activity and synthesized b60% of wax esters from the 3rd to 5th batch. The main composition of wax esters was ~48% oleyl laurate with 10% degradation at ~250°C. CONCLUSIONS: The liquid wax ester synthesis by commercial Lipozyme RM IM had higher effect than immobilized lipase EQ3, but both catalysts were stable within 2 batches in the optimum condition. The characteristic properties of wax esters showed potential for use as components in cosmetics and skin care products.


Sujets)
Cires , Esters/métabolisme , Huile de palme/synthèse chimique , Triacylglycerol lipase/métabolisme , Température , Enzymes immobilisées , Industrie Cosmétique
18.
Rev. colomb. anestesiol ; 48(2): 85-90, Jan.-June 2020. tab, graf
Article Dans Anglais | LILACS, COLNAL | ID: biblio-1115561

Résumé

Abstract Introduction: Orthotopic liver transplantation (OLT) is a procedure characterized by high bleeding rates and a significant likelihood of exposure to blood products. Objectives: This case series shows the experience at a referral center for Jehovah's Witnesses (JW) with end-stage liver disease, undergoing OLT. Materials and methods: A search was conducted in our database of JW undergoing OLT between July 2007 and August 2012. The information about their pre-operative condition and progress up to 30 days post-transplantation. Results: Four subjects were identified (3F/1M) with an average age of 42 years (range 22-55). All of them received a multidisciplinary management which included pre-operative optimization of red cell mass, antifibrinolytic prophylaxis, and cell salvage (mean volume of 344mL [range 113-520]). The average intraoperative bleeding volume was of 625mL (range 300-1000). One of the patients presented with a primary graft dysfunction and died, while the rest had a normal postoperative course. Conclusion: It is possible to offer OLT to patients who refuse to receive allogeneic blood transfusions, through a comprehensive approach that includes perioperative hematologic optimization and the use of blood conservation measures, without a significant impact on the outcomes.


Resumen Introducción: El trasplante hepático ortotópico (THO) es un procedimiento caracterizado por índices significativos de sangrado y alta probabilidad de exposición a hemocomponentes. Objetivos: Esta serie de casos muestra la experiencia de un centro de referencia en la atención de testigos de Jehová (TJ) con enfermedad hepática terminal llevados a THO. Materiales y métodos: Se realizó una búsqueda en nuestra base de datos de TJ que hubiesen sido llevados a THO entre julio de 2007 y agosto de 2012. Se registraron datos correspondientes a su estado preoperatorio, manejo perioperatorio y evolución hasta los 30 días postrasplante. Resultados: Se encontraron cuatro sujetos (3M/1H) con una edad promedio de 42 años (rango de 22-55). Todos recibieron un manejo multidisciplinario que incluyó la optimización preoperatoria de su masa eritrocitaria, profilaxis antifibrinolítica y salvamento celular [volumen promedio de 344 ml (rango de 113-520)]. El volumen promedio de sangrado intraoperatorio fue de 625 ml (rango de 300-1000). Uno de los pacientes presentó disfunción primaria del injerto y muerte, mientras que los demás tuvieron un curso posoperatorio convencional. Conclusiones: Es posible ofrecer la posibilidad de THO para sujetos que se niegan a recibir transfusiones alogénicas, por medio de un abordaje integral que incluya la optimización hematológica perioperatoria y la utilización de medidas de conservación sanguínea, sin que esto afecte significativamente los resultados.


Sujets)
Humains , Mâle , Femelle , Adulte d'âge moyen , Transplantation hépatique , Témoins de Jéhovah , Transfusion sanguine , Insuffisance hépatique , Substances viscoélastiques/synthèse chimique
19.
Rev. bras. ciênc. vet ; 27(2): 93-101, abr./jun. 2020. tab
Article Dans Portugais | LILACS, VETINDEX | ID: biblio-1491666

Résumé

During the Gorgonzola-type cheese preparation there are proteolysis and lipolysis which may be influenced by the type of starter culture chosen. Six manufacturing steps were selected to identify which of them is most suitable for biogenic amines (BA) formation (1- milk, 2- lactic acid bacterial culture and fungus addition, 3- curd, 4- dry salting, 5- maturation at 30 days and maturation at 60 days); perform research on enterobacteria; accomplish the research of BA-producing bacteria (BAPB); detect and quantify the most abundant BA (putrescine, cadaverine, tyramine, histamine, spermidine and spermine) in the six steps of Gorgonzola cheese production and in bacterial isolates using high performance liquid chromatography and UV-Vis SPD/10AV detector and define if the presence of enterobacteria and BAPB would be correlated with BA production in this cheese. The bacterial culture used increased its log population by 7 log cycles and reached its highest level in batch 2 during cheese maturation. There was a decrease in the enterobacterial population in 2 log cycles after 60 days of maturation in batch 1. Tyramine was the BA with the highest concentration 306.32 mg.Kg-1 quantified in step 6 (60 days maturation) in batch 1. Criterion is requiered in bacterial starter culture selection because it is a quality determinant factor in relation to BA production and more rigor in raw material


Durante a elaboração do queijo tipo Gorgonzola ocorre proteólise a partir das bactérias e dos fungos adicionados ao leite que podem levar a formação de aminas biogênicas (AB) neste tipo de queijo. Portanto, no presente estudo foi feito o acompanhamento com coleta de amostras em seis etapas na fabricação deste queijo paraidentificar em qual delas haveria maior formação de aminas biogênicas (AB). As amostras coletadas em três diferentes lotes foram o leite cru (1), leite pasteurizado adicionado de cultura de bactérias ácido-láticas (2), massa coalhada (3), queijo após a etapa de salga seca (4), queijo após 30 dias de maturação (5) e queijo após 60 dias de maturação (6). Também foram realizadas a pesquisa de enterobactérias e bactérias ácido-láticas com característica capacidade de descarboxilação de aminoácidos e produção de aminas biogênicas (BPAB); detecção e quantificação da AB mais abundante (putrescina, cadaverina, tiramina, histamina, espermidina e espermina) nas seis etapas de fabricação do queijo tipo Gorgonzola e nos isolados bacterianos utilizando cromatografia líquida de alta eficiência e detector UV-Vis SPD/10AV e a verificação se a presença de enterobactérias e BPAB estariam correlacionadas com a produção de AB nesse queijo. A cultura bacteriana utilizada cresceu aumentando em sete ciclos logarítmicos sua população e alcançou seu maior nível no lote 2 na etapa de maturação do queijo. Houve diminuição da população enterobactérias em 2 ciclos logarítmicos após 60 dias de maturação no lote 1. A tiramina foi a AB com concentração mais elevada 306,32 mg.Kg-1 quantificada na etapa 6 (60 dias de maturação) no lote 1. É necessário dar mais atenção em duas etapas na elaboração dos queijos: mais critério na seleção da cultura bacteriana iniciadora por ser um fator determinante na qualidade em relação à produção de AB e mais rigor na seleção da matéria-prima.


Sujets)
Amines biogènes/analyse , Amines biogènes/synthèse chimique , Chromatographie , Norme d'Identité et de Qualité pour les Produits et Services , Fromage/analyse
20.
Actual. osteol ; 16(1): 35-46, Ene - abr. 2020. graf, ilus
Article Dans Espagnol | LILACS | ID: biblio-1139966

Résumé

La erupción dental es un proceso estrictamente regulado y programado espacial y temporalmente. El objetivo del trabajo fue estudiar el efecto de la exposición prenatal a fluoruro de sodio (NaF) sobre los eventos morfológicos y celulares que ocurren en el hueso supracoronal del primer molar de crías de rata durante la etapa preeruptiva. Se emplearon crías (n=6-8 por grupo) provenientes de madres que bebieron crónicamente agua con diferentes concentraciones de F- en forma de NaF durante la gestación y lactancia: control y NaF (50 mg/L). En cortes histológicos de la mandíbula de crías de 3 y 10 días se analizaron parámetros de histomorfometría estática en la zona supracoronal de la canastilla ósea a la altura del primer molar inferior: volumen óseo trabecular [BV/TV (%)], número de osteoclastos por milímetro (N.Oc/mm) y las variables indirectas: número de trabéculas [Tb.N (1/mm)], espesor [Tb.Th (µm)] y separación trabecular [Tb.Sp (µm)]. En crías de 15 días se midió el grado de erupción [TED (µm)] del primer molar inferior. Los resultados se analizaron con el test "t" de Student considerando diferencias significativas a p<0,05. El análisis histomorfométrico demostró un incremento en el BV/TV (%) del hueso supracoronal (p<0,01) asociado con disminución del N.Oc/mm (p<0,01) en crías de 3 y 10 días expuestas prenatalmente al F-. El grado de erupción dental fue menor en animales expuestos prenatalmente al F- en comparación con los controles (p<0,01). En conclusión, los resultados observados en la mandíbula de crías expuestas durante la etapa prenatal y posnatal temprana al F- sugieren un efecto disruptivo sobre la actividad resortiva necesaria para formación del canal eruptivo. (AU)


Tooth eruption is a tightly regulated and spatially and temporally programmed process. The aim of this study was to examine the effect of prenatal NaF exposure on the morphological and cellular events that occur in the supracoronal area of bony crypt of the first rat molar during the preeruptive stage. Offspring from two groups of rats were used (6-8 per group): Control and 50 mg/L NaF. The treatment was performed during pregnancy and lactation. Suckling pups were euthanized at 3-, 10- and 15-days-old by cervical dislocation. Mandibles were removed and histologically processed to obtain buccolingual sections stained with H&E. In sections of first mandibular molar of 3- and 10-days-old pups, the following static histomorphometric parameters were evaluated: trabecular bone volume [BV/TV (%)] and number of osteoclasts (N.Oc/mm). Also, indirect parameters were obtained: trabecular number [Tb.N (1/mm)], trabecular thickness [Tb.Th (µm)], and trabecular separation [Tb.Sp (µm)]. The degree of tooth eruption [TED (µm)] was determined. Results are expressed as mean ± SE and analyzed by Student t-test. Histomorphometric analysis showed an increase in the BV/TV (%) of the bone crypt of 3- and 10- days-old pups exposed to NaF (p <0.01); this increase was associated with a decrease in the N.Oc/mm (p <0.01). TED of mandibular first molar was lower in prenatal NaF exposed group than in control group (p<0.01). In conclusion, the increased BV/TV and the lower N.Oc observed in the bone crypt of 3- and 10- days-old pups from mothers treated with NaF suggested a disruptive effect triggered by F- on the formation events of the eruptive pathway in the offspring. (AU)


Sujets)
Humains , Animaux , Mâle , Femelle , Nourrisson , Enfant d'âge préscolaire , Rats , Fluorure de sodium/effets indésirables , Éruption dentaire , Ostéoclastes/cytologie , Effets différés de l'exposition prénatale à des facteurs de risque , Fluorure de sodium/administration et posologie , Fluorure de sodium/métabolisme , Fluorure de sodium/urine , Fluorure de sodium/synthèse chimique , Rat Wistar , Mandibule/anatomie et histologie , Molaire/croissance et développement , Fluorose dentaire/diagnostic
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