Interaction between chlorhexidine and fluoride in a mouthrinse solution-a 4-day and 6-week randomized clinical pilot study.

OBJECTIVE: The aim of the present investigation was to study if there is a reduced clinical effect and fluoride retention of a mouthrinse solution containing both chlorhexidine (CHX) and sodium fluoride (NaF). MATERIAL AND METHODS: Two clinical trials were designed as double-blind, randomized, cross-over studies. In study I, 16 healthy subjects were asked to rinse twice daily for 1 min during 4 days of no tooth brushing with four solutions: (1) 0.12% CHX + 0.2% NaF, (2) 0.2% NaF, (3) 0.12% CHX, and (4) placebo. In study II, another 16 healthy subjects rinsed with the same four solutions twice daily after tooth brushing during a 6-week period. Plaque formation, gingivitis, and microbiological samples from plaque and saliva, as well as fluoride retention, were analyzed. RESULTS: Both studies showed that both CHX + NaF and CHX mouthrinses had the same clinical effect with regards to plaque formation and microflora in plaque and saliva. Similarly, fluoride retention was not altered by the CHX + NaF mouthrinse compared to the NaF solution. CONCLUSION: The combination of CHX and NaF in a mouthrinse showed the same clinical effect as the CHX solution. The retention of fluoride in the oral cavity was not affected by the combination of NaF and CHX. CLINICAL RELEVANCE: A mouthrinse solution containing a mixture of CHX and NaF may be an interesting product for risk patients for caries and periodontal disease. However, this should be verified in further long-term clinical studies.

Induction of Periodontitis via a Combination of Ligature and Lipopolysaccharide Injection in a Rat Model.

Periodontitis (PD) is a highly prevalent, chronic immune-inflammatory disease of the periodontium, that results in a loss of gingival soft tissue, periodontal ligament, cementum, and alveolar bone. In this study, a simple method of PD induction in rats is described. We provide detailed instructions for placement of the ligature model around the first maxillary molars (M1) and a combination of injections of lipopolysaccharide (LPS), derived from Porphyromonas gingivalis at the mesio-palatal side of the M1. The induction of periodontitis was maintained for 14 days, promoting the accumulation of bacteria biofilm and inflammation. To validate the animal model, IL-1ß, a key inflammatory mediator, was determined by an immunoassay in the gingival crevicular fluid (GCF), and alveolar bone loss was calculated using cone beam computed tomography (CBCT). This technique was effective in promoting gingiva recession, alveolar bone loss, and an increase in IL-1ß levels in the GCF at the end of the experimental procedure after 14 days. This method was effective in inducing PD, thus being able to be used in studies on disease progression mechanisms and future possible treatments.

Improved physical and osteoinductive properties of demineralized bone matrix by gelatin methacryloyl formulation.

The demineralized bone matrix (DBM) is the most widely used bone allograft, which is obtained by removing the mineral component of bone, leading to exposure of the proteins responsible for osteoinduction. For clinical use, DBM shall be formulated with a carrier that provides consistency and improves its osteoinduction. In this study, three DBM formulations with glycerol (Gly), hyaluronic acid (HA), and gelatin methacryloyl (GelMA) were evaluated measuring their physicochemical properties (microstructure, compressive strength, and serum cohesivity) and their osteoinductive capacity both in vitro using C2C12 cells and umbilical cord human mesenchymal stem cells and in vivo in an ectopic bone formation model in athymic mice. To assess the effectiveness of DBM in vitro in inducing the differentiation into osteoblasts, alkaline phosphatase (ALP) activity was assessed in combination with a cytotoxicity assay. In vivo, new bone formation was assessed by histological and radiological analysis. In the compression and in the serum cohesive assays, the GelMA DBM formulation showed its superiority over the other formulations. In addition, GelMA showed a more compact structure analysed by scanning electron microscopy. Higher cell toxicity was observed on Gly formulations in vitro, whereas GelMa and HA showed very low toxicity. All formulations significantly improved ALP activity compared with control. In the in vivo studies, GelMA showed the greatest osteoinductive potential with a higher percentage of new bone and bone marrow formation. Our results suggest GelMA is useful as a carrier for DBM designed to promote the formation of the new bone.

Efecto de un tratamiento contextual para la regulación de la ira y la inflexibilidad psicológica en adultos jóvenes colombianos

Antecedentes: en la actualidad, son escasas las intervenciones para el manejo de la regulación problemática de la ira y la inflexibilidad psicológica en adultos jóvenes afectados. Objetivo: evaluar la eficacia de una intervención breve, en formato grupal y virtual para la regulación problemática de la ira y la reducción de la inflexibilidad psicológica. Método: un grupo de 40 adultos jóvenes colombianos (40% hombres; 60%mujeres; M = 25.3 años; DE = 3.35) fueron asignados aleatoriamente a una de dos condiciones: intervención basada en la terapia de aceptación y compromiso (ACT) para regulación de la ira y la reducción de la inflexibilidad psicológica y lista de espera. Se evaluaron la evitación experiencial, la fusión cognitiva, la conexión con el momento presente, los valores y la percepción de efectos de la expresión problemática de la ira. Resultados: se encontraron diferencias significativas contamaños de efecto grandes en las variables de evitación experiencial, defusión cognitiva, contacto con el momento presente y obstrucción en valores. Las variables de progreso en valores y percepción de efectos de la ira presentaron cambios en el grupo experimental, pero no en su comparación con el grupo control. Conclusión: los resultados aportaron evidencia sobre la eficacia de esta intervención, aunque se requieren más estudios que así lo confirmen. Palabras clave: terapia de aceptación y compromiso;regulación de la ira; inflexibilidad psicológica; adultos jóvenes;intervención virtual.

Background: At present, interventions for the management of problematic anger regulation and psychological inflexibility inaffected young adults are scarce. Objetive: to evaluate the efficacy of a brief intervention, in a group and virtual format, for anger regulation and psychological inflexibility reduction. Method: A group of 40 Colombian young adults (40% male; 60% female; M = 25.3 years; SD = 3.35) were randomly assigned to one of two conditions: Acceptance and Commitment Therapy-based intervention for anger regulation andpsychological inflexibility reduction and waiting list. Experiential avoidance, cognitive fusion, connection to thepresent moment, values, and perception of negative effects of problematic anger expression were assessed. Results: Significant differences with large effect sizes were found in the experiential avoidance, cognitive defusion, contact with the present moment, and obstruction in values variables. The variables of progressin values and perception of the effects of anger presented changes in the experimental group, but not in their comparison with the control group. Conclusions: the results provide devidence on the efficacy of this intervention, although more studies are required to confirm this. Keywords: Acceptance and Commitment Therapy; Angerregulation; Psychological inflexibility; Young adults; Virtualintervention.

EMD in periodontal regenerative surgery modulates cytokine profiles: A randomised controlled clinical trial.

The enamel matrix derivative (EMD) contains hundreds of peptides in different levels of proteolytic processing that may provide a range of biological effects of importance in wound healing. The aim of the present study was to compare the effect of EMD and its fractions on the cytokine profiles from human gingival fibroblasts in vitro and in gingival crevicular fluid (GCF) in a randomized controlled split-mouth clinical study (n = 12). Levels of cytokines in cell culture medium and in GCF were measured by Luminex over a 2-week period. In the clinical study, levels of pro-inflammatory cytokines and chemokines were increased, whereas the levels of transforming growth factor-α (TGF-α) and platelet-derived growth factor-BB (PDGF-BB) were reduced. The in vitro study showed that EMD and its high and low molecular weight fractions reduced the secretion of pro-inflammatory cytokines and chemokines compared to untreated cells. EMD had an effect on levels of cytokines related to fibroplasia, angiogenesis, inflammation and chemotaxis both in vitro and in vivo, however, the anti-inflammatory effect induced by EMD observed in the in vitro study could not be confirmed clinically.

Subfractions of enamel matrix derivative differentially influence cytokine secretion from human oral fibroblasts.

Enamel matrix derivative is used to promote periodontal regeneration during the corrective phase of the treatment of periodontal defects. Our main goal was to analyze the bioactivity of different molecular weight fractions of enamel matrix derivative. Enamel matrix derivative, a complex mixture of proteins, was separated into 13 fractions using size-exclusion chromatography and characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and liquid chromatography-electrospray ionization-tandem mass spectrometry. Human periodontal ligament fibroblasts were treated with either enamel matrix derivative or the different fractions. Proliferation and cytokine secretion to the cell culture medium were measured and compared to untreated cells. The liquid chromatography-electrospray ionization-tandem mass spectrometry analyses revealed that the most abundant peptides were amelogenin and leucine-rich amelogenin peptide related. The fractions containing proteins above 20 kDa induced an increase in vascular endothelial growth factor and interleukin-6 secretion, whereas lower molecular weight fractions enhanced proliferation and secretion of interleukin-8 and monocyte chemoattractant protein-1 and reduced interleukin-4 release. The various molecular components in the enamel matrix derivative formulation might contribute to reported effects on tissue regeneration through their influence on vascularization, the immune response, and chemotaxis.

Suture materials affect peri-implant bone healing and implant osseointegration.

The aim of this study was to evaluate the effects of the remnants of two suture materials on osseointegration of titanium implants in a rabbit tibial model. Calibrated defects were prepared in the tibia of five Chinchilla rabbits. Filaments of nonresorbable (NR) nylon or resorbable (R) chitosan were placed at the bone to implant interface, whereas control sites had no suture material. After a healing period of 4 weeks, a pull-out test procedure was performed followed by enzymatic analyses of the wound fluid and relative quantification of mRNA levels for bone-related and cytokine markers from the peri-implant bone. A trend toward a reduced pull-out force was observed in the NR group (NR: 23.0 ± 12.8 N; R: 33.9 ± 11.3 N; control: 33.6 ± 24.0 N). Similarly, the bone resorption marker vacuolar type H+-ATPase was increased in the NR group compared with that in the control group (P = 0.041). The R group showed trends for lower alkaline phosphatase activity and osteocalcin expression and higher total protein content and RNA compared with the control group. In this submerged healing model, peri-implant bone healing was marginally affected by the two suture materials tested. However, there was a tendency toward better osseointegration and lower expression of bone resorption markers in the R group compared with the control group.

Proline-Rich Peptide Mimics Effects of Enamel Matrix Derivative on Rat Oral Mucosa Incisional Wound Healing.

BACKGROUND: Proline-rich peptides have been shown to promote periodontal regeneration. However, their effect on soft tissue wound healing has not yet been investigated. The aim of this study is to evaluate the effect of enamel matrix derivative (EMD), tyrosine-rich amelogenin peptide (TRAP), and a synthetic proline-rich peptide (P2) on acute wound healing after a full-thickness flap procedure in an incisional rat model. METHODS: This experimental study has a split-mouth, randomized, placebo-controlled design. Test and control wounds were created on the palatal mucosa of 54 Sprague-Dawley rats. Wounds were histologically processed, and reepithelialization, leukocyte infiltration, and angiogenesis were assessed at days 1, 3, and 7 post-surgery. RESULTS: EMD and P2 significantly promoted early wound closure at day 1 (P <0.001 and P = 0.004, respectively). EMD maintained a significant acceleration of reepithelialization at day 3 (P = 0.004). Wounds treated by EMD and P2 showed increased angiogenesis during the first 3 days of healing (P = 0.03 and 0.001, respectively). Leukocyte infiltration was decreased in EMD-treated wounds at day 1 (P = 0.03), and P2 and TRAP induced a similar effect at days 3 (P = 0.002 and P <0.0001, respectively) and 7 (P = 0.005 and P <0.001). CONCLUSION: EMD and P2 promoted reepithelialization and neovascularization in full-thickness surgical wounds on rat oral mucosa.

Factores que impulsan la internacionalización en las pymes industriales del Eje Cafetero colombiano: estudio de caso / Factors driving industrial SMEs in the Colombian Coffee Region towards internationalization / Fatores que impulsionam a Internacionalização nas PMEs Industriais da Região cafeeira colombiana

Resumen Se presentan los factores que han impulsado a algunas pymes industriales de los departamentos de Caldas, Quindío y Risaralda a emprender procesos de internacionalización, a partir de un estudio de caso múltiple exploratorio y de corte cualitativo descriptivo. Los resultados sugieren que las pymes industriales exportadoras consultadas hacen alguna adaptación a los productos que exportan y cuentan con políticas de calidad en los procesos de producción. Gran parte de ellas sostiene que no tiene planes para el manejo de conflictos a nivel internacional y que las exportaciones han contribuido a mejorar la productividad de la empresa; otras afirman tener dificultades con la capacidad de negociación internacional, aunque desarrollan productos innovadores y se interesan en conocer a sus competidores en el exterior: Un buen número reconoce que es difícil encontrar personal calificado para laborar en esta área, mientras que unas pocas realizan estudios sobre el mercado extranjero, concluyéndose que aunque la mayor parte de las pymes industriales exportadoras del Eje Cafetero han logrado abrirse a los mercados internacionales gracias al desarrollo competitivo que han tenido inicialmente a nivel regional, debe mejorarse el perfil de los directivos del área internacional e incrementarse las estrategias de promoción y distribución para lograr y mantener ventajas competitivas. Clasificación JEL: F2

Abstract This paper presents the factors which have driven some industrial SMEs (Small and Medium-sized enterprises) in the departments of Caldas, Quindío and Risaralda to start internationalization processes, based on a multiple case study with an exploratory qualitative descriptive scope. The results suggest that industrial and exporting SMEs of this study adapt the products to be exported and follow quality policies in the production processes. Many of these companies have stated that there are no plans for dealing with conflicts at an international level and that exports have contributed to improving the company's productivity of Others have claimed to have difficulties with international negotiation skills, despite having developed innovative products and being interested in knowing their competitors abroad. A large number of these SMEs recognize the difficulties in finding qualified personnel to work in this area, while a small number of them carry out studies on the foreign market. The conclusion is that although most of the industrial & exporting SMEs of the Colombian Coffee Region consulted have managed to open up to international markets, thanks to their initial competitive development at the regional level, the administrative staff profile of the international area must be improved and promotion and distribution strategies increased in order to achieve and maintain competitive advantages. JEL Classification: F2

Resumo Este artigo apresenta os fatores que levaram algumas PMEs industriais dos departamentos de Caldas, Quindío e Risaralda a empreender processos de internacionalização, com base em um estudo de casos múltiplos de natureza exploratória qualitativa descritiva. Os resultados do estudo sugerem que as PMEs Industriais Exportadoras que foram consultadas fazem alguma adaptação aos produtos que exportam e possuem políticas de qualidade nos processos produtivos; Muitas delas sustentam que não têm planos para a gestão de conflitos a nível internacional e que as exportações contribuíram para melhorar a produtividade da empresa; outras afirmam ter dificuldades com as habilidades de negociação internacional, embora desenvolvam produtos inovadores e estejam interessados em conhecer seus concorrentes no exterior: Um bom número dessas PMEs reconhece que é difícil encontrar pessoal qualificado para trabalhar nessa área, enquanto poucas fazem estudos sobre o mercado externo, concluindo que, embora a maioria das PMEs industriais exportadoras da Região Cafeeira consultadas tenham conseguido se abrir aos mercados internacionais graças ao desenvolvimento competitivo que inicialmente tiveram no nível regional, o perfil dos gestores da área internacional deve ser melhorado e as estratégias de promoção e distribuição devem ser aumentadas para alcançar e manter as vantagens competitivas. Classificações JEL: F2

Análisis de los factores asociados a las relaciones de pareja homosexual (gays y lesbianas) en la ciudad de Bogotá / Analysis of factors associated with same-sex relationships (gays and lesbians) in Bogotá

Esta investigación caracteriza las relaciones de pareja entre personas del mismo sexo, en el contexto bogotano, comparando un grupo de personas con pareja actual y otro sin pareja. Mediante un muestreo no probabilístico por conveniencia a través de un diseño de bola de nieve, se aplicó una entrevista en profundidad a una muestra de 60 homosexuales (30 hombres, 30 mujeres) y se indagó sobre aspectos relacionados con la experiencia afectiva (formación de la relación, satisfacción, manejo de conflictos). Los resultados muestran que, en general, los participantes tienen una visión positiva de su vida en pareja, sin diferencias importantes en la percepción de los dos grupos en los aspectos evaluados.

This research characterizes the same sex couple relationships in Bogota’s context by comparing a group of people with current partner and one without a partner. Using a non-probabilistic convenience sampling through a snowball design a in-depth interview was a applied to a sample of 60 homosexual (30 men, 30 women). They were asked about aspects of the affective experience (formation of the relationship, satisfaction, conflict management). The results show the participants have a positive view of their couple’s life, without significant differences in the perception of the two groups in the aspects evaluated.