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We introduce a new modelling for long-term survival models, assuming that the number of competing causes follows a mixture of Poisson and the Birnbaum-Saunders distribution. In this context, we present some statistical properties of our model and demonstrate that the promotion time model emerges as a limiting case. We delve into detailed discussions of specific models within this class. Notably, we examine the expected number of competing causes, which depends on covariates. This allows for direct modeling of the cure rate as a function of covariates. We present an Expectation-Maximization (EM) algorithm for parameter estimation, to discuss the estimation via maximum likelihood (ML) and provide insights into parameter inference for this model. Additionally, we outline sufficient conditions for ensuring the consistency and asymptotic normal distribution of ML estimators. To evaluate the performance of our estimation method, we conduct a Monte Carlo simulation to provide asymptotic properties and a power study of LR test by contrasting our methodology against the promotion time model. To demonstrate the practical applicability of our model, we apply it to a real medical dataset from a population-based study of incidence of breast cancer in São Paulo, Brazil. Our results illustrate that the proposed model can outperform traditional approaches in terms of model fitting, highlighting its potential utility in real-world scenarios.

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O conceito de fantasma possui uma importância crucial para o enquadramento da experiência em psicanálise. Este artigo pretende situar o lugar e a função do fantasma neurótico na experiência analítica partindo da função da fala, tal como proposto por Lacan. Para tanto, selecionamos alguns textos e seminários de Lacan situados entre os anos de 1953 a 1964. Nossa hipótese de trabalho consiste na suposição de que, ao enquadrar uma realidade constituída inconscientemente enquanto resposta ao desejo do Outro, o fantasma serve para perpetuar ao neurótico um senso de ser idêntico a si mesmo à medida em que tende a promover um apagamento de contradições provenientes da posição que, como sujeito, ocupa em relação a este desejo. Ao ser concebida como irrupção de um objeto com valor de não-eu no enquadre fantasmático, a angústia produz um efeito reverso, constituindo, por conseguinte, tanto uma contraprova quanto um apoio na demonstração dessa hipótese.

Le concept de fantôme revêt une importance cruciale pour encadrer l'expérience en psychanalyse. Cet article veut situer la place et la fonction du fantasme névrotique dans l'expérience analytique à partir de la fonction de la parole, comme le propose Lacan. Pour cela, nous avons sélectionné quelques textes et séminaires de Lacan situés entre les années 1953 et 1964. Notre hypothèse de travail est qu'en encadrant une réalité inconsciemment constituée en réponse au désir de l'Autre, le fantôme sert à perpétuer chez le névrosé un sentiment d'être identique à lui-même dans la mesure où il tend à favoriser un effacement des contradictions nées de la position qu'il occupe, en tant que sujet, par rapport à ce désir. Conçue comme l'irruption d'un objet ayant valeur de non-moi dans le cadre fantasmatique, l'angoisse produit un effet inverse, constituant donc à la fois une contre-preuve et un support à la démonstration de cette hypothèse.

The concept of the phantasm holds a crucial importance for framing the experience in psychoanalysis. This article aims to situate the place and function of the neurotic phantasm in the analytical experience, starting from the function of speech as proposed by Lacan. To do so, we have selected some texts and seminars by Lacan between the years of 1953 to 1964. Our working hypothesis is that by framing an unconsciously constituted reality as a response to the Other's desire, the phantasm serves to perpetuate in the neurotic subject a sense of being identical to themselves as it tends to promote an erasure of contradictions arising from the subject's position in relation to this desire. When conceived as the irruption of an object with a non-ego value in the phantasmatic frame, anxiety produces a reverse effect, thereby constituting both a counterproof and a support in demonstrating this hypothesis.

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The radiological protection has the purpose of safeguarding the physical well-being of the user, preventing exposure to detrimental levels of ionizing radiation. This study introduces a novel, cost-effective category of lead-free elastomeric material designed for radiation shielding. The filler compounds utilized are notably lighter than conventional lead-based materials, enhancing user ergonomics during application. They comprise of a blend of barium sulfate combined or not with magnesium oxide with addition-cure liquid silicone rubber. To ensure the effectiveness of the radiation shielding, X-ray transmission measurements were performed for the different thicknesses of the materials and the results compared with Monte Carlo simulations. Additionally, the physical properties of the new materials, such as density, homogeneity, tensile strength, viscosity, and wettability, were also evaluated. The findings indicate that both materials fulfill the requirement for application in radiation protection garments.

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Hepatitis B Surface Antigen (HBsAg) seroclearance is the highest treatment goal recommended by the current guidelines for hepatitis B. Levels of antibodies to HBsAg (anti-HBs) are strongly associated with HBsAg recurrence, but hepatitis B vaccination may increase the anti-HBs seroconversion rate and reduce recurrence. We conducted a retrospective clinical study to ascertain the effect of this vaccination on the seroconversion rate and levels of protective anti-HBs after HBsAg. In this retrospective study, we distributed a questionnaire through an online survey platform to collect information related to hepatitis B vaccination in patients with functional cure of hepatitis B with Interferon-α (IFNα) therapy. We enrolled 320 patients who achieved functional cure from IFNα therapy. Of these, 219 patients had received hepatitis B vaccination according to their personal preference and drug accessibility after HBsAg seroclearance, whereas the remaining 101 patients did not receive hepatitis B vaccination. The anti-HBs seroconversion rate of 78.1% in the vaccinated group was significantly greater than that in the unvaccinated group (41.6%) (p < 0.001). Stratified comparisons with anti-HBs of ≥ 100 IU/L and ≥ 300 IU/L showed that both proportions in the vaccinated group were greater than those in the unvaccinated group (71.2% vs. 32.7% and 56.2% vs. 17.8%, respectively, all p-values < 0.001). Logistic regression analysis showed that the odds ratio of vaccination was 4.427, which was the strongest influencing factor for anti-HBs, reaching 100 IU/L or higher. Hepatitis B vaccination in patients after HBsAg seroclearance not only increased the anti-HBs seroconversion rate but also significantly increased antibody levels, with good safety, indicating the clinical value of vaccine therapy for patients with functional cure.

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OBJECTIVES: To investigate the changes in the coagulation function and hemodynamic parameters in patients with Hemorrhagic Traumatic Shock (HTS) after restrictive fluid resuscitation. METHODS: A total of 139 patients with HTS admitted to our hospital were enrolled, among which 69 HTS patients were divided into the control group and the remaining 70 HTS patients as the observation group. Patients in the control group underwent regular fluid resuscitation, while those in the observation group underwent restrictive fluid resuscitation. RESULTS: During treatment, 70 patients in the observation group had a lower bleeding amount, infusion amount, and blood transfusion volume than those in the control group (p < 0.05). After treatment, patients in the observation group had better hemodynamic parameters and blood coagulation than those in the control group (p < 0.05), and the incidence rate in the observation group was only 12.9%, which was significantly lower than 60.87% in the control group, while the cure rate in the observation group was 100%, which was significantly higher than that in the control group (p < 0.05). CONCLUSIONS: Restrictive fluid resuscitation could remarkably increase the cure rate and reduce the bleeding amount during HTS treatment, thereby benefiting the recovery of the patient's blood coagulation.

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Achieving a cure for HIV infection is a global priority. There is substantial evidence supporting a central role for CD8+ T cells in the natural control of HIV, suggesting the rationale that these cells may be exploited to achieve remission or cure of this infection. In this work, we review the major challenges for achieving an HIV cure, the models of HIV remission, and the mechanisms of HIV control mediated by CD8+ T cells. In addition, we discuss strategies based on this cell population that could be used in the search for an HIV cure. Finally, we analyze the current challenges and perspectives to translate this basic knowledge toward scalable HIV cure strategies.

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Objetivo: Avaliar a profundidade de polimerização em diferentes espessuras da resina composta Tetric® N-Flow Bulk Fill com adição de xilitol em diferentes concentrações. Metodologia: A resina Tetric® N-Flow Bulk Fill foi misturada às concentrações do xilitol (0% [Controle], 2,5% e 5% g/g) por espatulação manual durante 1 min em uma câmara escura. Amostras cilíndricas foram confeccionadas em moldes de polimetilmetacrilato de 5 mm de diâmetro x 1 mm, 2 mm, 3 mm e 4 mm de espessura nas concentrações de xilitol propostas totalizando 12 grupos (n=3), fotoativadas por 10 s e armazenadas a 37º C por 24 h. Os espécimes foram submetidos ao teste de microdureza Vickers, sendo a profundidade de polimerização obtida por meio da razão base/topo. Foram utilizados testes não paramétricos de Kruskal Wallis para comparação das diferentes espessuras na mesma concentração e das diferentes concentrações na mesma espessura (p<0,05) através do software BioEstat 5.3. Resultados: Não houve diferença estatisticamente significativa entre as diferentes espessuras na mesma concentração, bem como entre as diferentes concentrações na mesma espessura (p=1,000). Todos os espécimes apresentaram profundidade de polimerização adequada (razão de dureza ≥80%), com exceção das amostras com 4 mm de espessura contendo 2,5 e 5% de xilitol, que apresentaram razão de dureza média de 79% e 74%, respectivamente. Conclusão: Nas condições deste estudo, pode-se concluir que a adição de xilitol a uma resina bulk fill fluida pode afetar a profundidade de polimerização em 4 mm (AU).

Objective: To evaluate the depth of cure at different thicknesses of the Tetric® NFlow Bulk Fill composite resin with the addition of xylitol at different concentrations. Materials and Methods: The Tetric™ N-Flow Bulk Fill resin was mixed with xylitol concentrations (0% [Control], 2.5%, and 5% g/g) by manual spatulation for 1 minute in a portable darkroom. Cylindrical samples were prepared in polymethyl methacrylate molds with diameters of 5 mm and thicknesses of 1 mm, 2 mm, 3 mm, and 4 mm at the proposed xylitol concentrations, totaling 12 groups (n=3), photoactivated for 10 seconds, and stored at 37°C for 24 hours. The specimens were subjected to Vickers microhardness testing, and the depth of cure was obtained by calculating the base/top ratio. Non-parametric Kruskal-Wallis tests were used to compare different thicknesses at the same concentration and different concentrations at the same thickness (p<0,05) using BioEstat 5.3 software. Results: There was no statistically significant difference between different thicknesses at the same concentration, as well as between different concentrations at the same thickness (p=1,000). All specimens exhibited adequate depth of cure (hardness ratio ≥80%), except for the samples with 4 mm thickness containing 2.5% and 5% xylitol, which showed average hardness ratios of 79% and 74%, respectively. Conclusion: Under the conditions of this study, it can be concluded that the addition of xylitol to a fluid bulk fill resin can affect the depth of cure at 4 mm (AU).

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Background: Plasmodium vivax malaria is challenging to control and eliminate. Treatment with radical cure drugs fails to target the hidden asymptomatic and hypnozoite reservoirs in populations. PvSeroTAT, a novel serological test-and-treat intervention using a serological diagnostic to screen hypnozoite carriers for radical cure eligibility and treatment, could accelerate P. vivax elimination. Methods: Using a previously developed mathematical model of P. vivax transmission adapted to the Brazilian context as a case study for implementation, we evaluate the public health impact of various deployment strategies of PvSeroTAT as a mass campaign. We compare relative reductions in prevalence, cases averted, glucose-6-phosphate dehydrogenase (G6PD) tests, and treatment doses of PvSeroTAT campaigns to strengthened case management alone or mass drug administration (MDA) campaigns across different settings. Findings: Deploying a single round of PvSeroTAT with 80% coverage to treat cases with a high efficacy radical cure regimen with primaquine is predicted to reduce point population prevalence by 22.5% [95% UI: 20.2%-24.8%] in a peri-urban setting with high transmission and by 25.2% [95% UI: 9.6%-42.2%] in an occupational setting with moderate transmission. In the latter example, while a single PvSeroTAT achieves 9.2% less impact on prevalence and averts 300 less cases per 100,000 than a single MDA (25.2% [95% UI: 9.6%-42.2%] point prevalence reduction versus 34.4% [95% UI: 24.9%-44%]), PvSeroTAT requires 4.6 times less radical cure treatments and G6PD tests. Layering strengthened case management and deploying four rounds of PvSeroTAT six months apart is predicted to reduce point prevalence by a mean of 74.1% [95% UI: 61.3%-86.3%] or more in low transmission settings with less than 10 cases per 1000 population. Interpretation: Modelling predicts that mass campaigns with PvSeroTAT are predicted to reduce P. vivax parasite prevalence across a range of transmission settings and require fewer resources than MDA. In combination with strengthened case management, mass campaigns of serological test-and-treat interventions can accelerate towards P. vivax elimination. Funding: This project was funded in part by the Bill and Melinda Gates Foundation and the National Health and Medical Research Council.

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Violence is a significant social problem in many cities throughout the world. In seeking to prevent or control violence, communities have put in place a variety of interventions. Many of these rely on the formal criminal justice process to arrest, prosecute, and imprison offenders. However, formal social control is well known to be an incomplete solution to violence. As a result, some communities have experimented with community-based solutions. One such approach is Cure Violence, an initiative that treats violence as a public health issue. Based on methods used to prevent the spread of infectious disease, Cure Violence seeks to stop the spread of violence within communities. This study presents qualitative results on the implementation of Cure Violence in Trinidad and Tobago, a two-island nation in the southeastern Caribbean near Venezuela. We conducted 36 in-depth semi-structured interviews and two focus groups with a variety of stakeholders, including program staff, residents, family members of victims, and police. Our findings suggest that the implementation of Cure Violence in Trinidad and Tobago led to educational and employment support for community members and a reduction in violence, particularly retaliation killings in the target communities. Our results are useful for understanding the factors that shape the implementation of community-based violence reduction initiatives like Cure Violence.

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OBJECTIVE: To evaluate the effect of delayed light-curing of dual-cure bulk-fill composites on internal adaptation and microhardness (KHN) in depth. MATERIALS AND METHODS: Bulk-fill composites were placed in 35 box-shaped preparations and cured according to the following protocols (n = 5): Filtek Bulk-Fill light-cured immediately after insertion (FBF); Bulk-EZ light-cured immediately after insertion (BEZ-I); Bulk-EZ light-cured 90 s after insertion (BEZ-DP); Bulk-EZ self-cured (BEZ-SC); HyperFIL light-cured immediately after insertion (HF-I); HyperFIL light-cured 90 s after insertion (HF-DP); HyperFIL self-cured (HF-SC). After 24 h, the samples were axially sectioned, and the internal adaptation was evaluated using replicas under a scanning electron microscope. The KHN was evaluated at six depths (0.3 mm, 1 mm, 2 mm, 3 mm, 4 mm, and 5 mm). The statistical analysis was performed using α = 0.05. RESULTS: The KHN significantly decreased with depth, except in self-curing mode, when it was similar at all depths. Delayed light-curing significantly increased the KHN at higher depths. The internal adaptation was material-dependent. Light-curing did not influence the internal adaptation of HyperFIL, whereas delayed light-curing significantly reduced the internal gaps (%) of Bulk-EZ. CONCLUSION: Delayed light-curing improved the depth of cure of dual-cure resin composites. Light-curing did not influence the internal adaptation of HyperFIL, but delayed light-curing improved the internal adaptation of Bulk-EZ. CLINICAL SIGNIFICANCE: Light-curing is fundamental for improving the mechanical properties of dual-cure resin composites. Moreover, depending on the dual-cure resin composite, the delay in light-curing can reduce the internal gaps.

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Over the last decades, the challenges in survival models have been changing considerably and full probabilistic modeling is crucial in many medical applications. Motivated from a new biological interpretation of cancer metastasis, we introduce a general method for obtaining more flexible cure rate models. The proposal model extended the promotion time cure rate model. Furthermore, it includes several well-known models as special cases and defines many new special models. We derive several properties of the hazard function for the proposed model and establish mathematical relationships with the promotion time cure rate model. We consider a frequentist approach to perform inferences, and the maximum likelihood method is employed to estimate the model parameters. Simulation studies are conducted to evaluate its performance with a discussion of the obtained results. A real dataset from population-based study of incident cases of melanoma diagnosed in the state of São Paulo, Brazil, is discussed in detail.

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Abstract Objectives To investigate the changes in the coagulation function and hemodynamic parameters in patients with Hemorrhagic Traumatic Shock (HTS) after restrictive fluid resuscitation. Methods A total of 139 patients with HTS admitted to our hospital were enrolled, among which 69 HTS patients were divided into the control group and the remaining 70 HTS patients as the observation group. Patients in the control group underwent regular fluid resuscitation, while those in the observation group underwent restrictive fluid resuscitation. Results During treatment, 70 patients in the observation group had a lower bleeding amount, infusion amount, and blood transfusion volume than those in the control group (p < 0.05). After treatment, patients in the observation group had better hemodynamic parameters and blood coagulation than those in the control group (p < 0.05), and the incidence rate in the observation group was only 12.9%, which was significantly lower than 60.87% in the control group, while the cure rate in the observation group was 100%, which was significantly higher than that in the control group (p < 0.05). Conclusions Restrictive fluid resuscitation could remarkably increase the cure rate and reduce the bleeding amount during HTS treatment, thereby benefiting the recovery of the patient's blood coagulation.

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ABSTRACT This work aims to explore the dynamics of the cure in psychoanalysis, passing through a literary perspective. We begin by locating the idea of cure in psychoanalysis as the cure of the intractable, by thinking the logic of the cure through an aesthetic dimension. Next, we advance the idea of a literary subject, with the myth as a guiding element of a literary body that sustains its own existence. We adopt Kafka's idea of minor literature to understand the fragmented subject inserted in the culture. We then propose the neologism 'vereedades', playing on the proximity of the words 'truth' and 'path' in Portuguese ('verdade' and 'veredas') to explore curative dynamics, in which the subject explores his/her own style.

RESUMO Este trabalho visa explorar a dinâmica da cura em psicanálise, passando por uma perspectiva literária. Iniciamos localizando a ideia de cura em psicanálise como a cura do intratável, pensando a lógica da cura via uma dimensão estética. Na sequência, seguimos com a noção de sujeito literário, com o mito como um norte de um corpo literário que sustenta a própria existência do sujeito. Adotamos a ideia de uma literatura menor de Kaka para compreender o sujeito fragmentado em sua inserção na cultura. Então propomos o neologismo 'veredades', brincando com a proximidade das palavras 'verdade' e 'veredas' para explorar a dinâmica da cura, em que o sujeito explora seu próprio estilo.

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Abstract Hepatitis B Surface Antigen (HBsAg) seroclearance is the highest treatment goal recommended by the current guidelines for hepatitis B. Levels of antibodies to HBsAg (anti-HBs) are strongly associated with HBsAg recurrence, but hepatitis B vaccination may increase the anti-HBs seroconversion rate and reduce recurrence. We conducted a retrospective clinical study to ascertain the effect of this vaccination on the seroconversion rate and levels of protective anti-HBs after HBsAg. In this retrospective study, we distributed a questionnaire through an online survey platform to collect information related to hepatitis B vaccination in patients with functional cure of hepatitis B with Interferon-α (IFNα) therapy. We enrolled 320 patients who achieved functional cure from IFNα therapy. Of these, 219 patients had received hepatitis B vaccination according to their personal preference and drug accessibility after HBsAg seroclearance, whereas the remaining 101 patients did not receive hepatitis B vaccination. The anti-HBs seroconversion rate of 78.1% in the vaccinated group was significantly greater than that in the unvaccinated group (41.6%) (p < 0.001). Stratified comparisons with anti-HBs of ≥ 100 IU/L and ≥ 300 IU/L showed that both proportions in the vaccinated group were greater than those in the unvaccinated group (71.2% vs. 32.7% and 56.2% vs. 17.8%, respectively, all p-values < 0.001). Logistic regression analysis showed that the odds ratio of vaccination was 4.427, which was the strongest influencing factor for anti-HBs, reaching 100 IU/L or higher. Hepatitis B vaccination in patients after HBsAg seroclearance not only increased the anti-HBs seroconversion rate but also significantly increased antibody levels, with good safety, indicating the clinical value of vaccine therapy for patients with functional cure.

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The study analyzed the influence of temperature on the depth of cure of bulk-fill composite resins. Three discs (ISO 4049/2000) from each group were made, and four restorative materials were investigated: Opus Bulk-Fill Flow, Opus Bulk-Fill APS, Filtek™ One Bulk-Fill, and Filtek™ Bulk-Fill Flow. They were light-cured (Gnatus ± 1,200 mW/cm2) for 20 seconds, varying the temperature (23°C and 5°C) and simulating the use of the product both at room temperature and under refrigeration. The materials were inserted in aluminum matrices with 10 mm in depth and 4 mm in diameter. A clear film strip and a glass microscope slide were positioned at the top and bottom surfaces. The material was condensed and light-cured with the tip of the light source in close contact, for 20 seconds on the top surface. Immediately after irradiation, the samples were removed from the mold, and the uncured part was removed with a plastic spatula. The measurement was performed with a micrometer ± 0.1 mm, and the value was divided by 2. The data were analyzed with two-way ANOVA at a significance of 0.05. There was a statistical difference in the temperature between the results obtained in Opus Bulk-Fill APS (p <0.001) and Filtek™ Bulk-Fill Flow (p = 0.018) resins. For the temperature of 5°C, Filtek™ Bulk-Fill Flow showed a statistical difference compared to the other resins, while Opus Bulk-Fill Flow and Opus Bulk-Fill APS did not. For the temperature of 23°C, Filtek™ Bulk-Fill Flow maintained the statistical difference from the others, but Filtek™ One Bulk-Fill and Opus Bulk-Fill APS did not present statistical differences. Storing the Filtek™ Bulk-Fill Flow composite resin in the refrigerator caused a greater depth of cure than the other resins, and the depth of cure decreased at room temperature. As for Opus Bulk-Fill APS, the depth of cure decreased proportionally to the temperature decrease. The temperature may affect the depth of cure of some composite resins.

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The addition of Superabsorbent Polymer (SAP) decreases the effect of autogenous shrinkage present in pastes, mortars, and concretes. In this study we investigated the influence of the addition of SAP in self-compacting cement paste mixtures. Eighteen 5 × 10 cylindrical specimens were molded in all, three for each mixture (CPII base, CPII 0.15%SAP/600µm, CPII 0.15%SAP/800 µm, CPV base, CPV 0.15%SAP/600 µm, CPV 0.15%SAP/800 µm). Two types of cement were tested, CP II-Z and CP V-ARI with 0.15% of weight replaced per two diameters of SAP (600 µm and 800 µm). The samples followed the standards required. Mini slump tests were carried out in the fresh state, and uniaxial compressive strength, elastic modulus, specific mass, absorption, and air content in the hardened state after 28 days. The results obtained show the SAP is high indicated to replaced cement in small % of weight i/to fresh and hardened paste. Likewise, the group mix n° 3 composed of CPII 0.15% of SAP with 800 µm diameter presented the best result.

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The present study introduces a new multivariate mixture cure rate model based on the Chen probability distribution to model recurrent event data in the presence of cure fraction. In this context, we provide an alternative for the use of some usual modeling approaches as the semiparametric Cox proportional hazards model commonly used in lifetime data analysis, considering a new bivariate parametric model to be used in the data analysis of bivariate lifetime data assuming a mixture structure for the bivariate data in presence of covariates, censored data and cure fraction. Under a Bayesian setting, the proposed methodology was considered to analyze two real medical datasets from a retrospective cohort study related to leukemia and diabetic retinopathy diseases. The model validation process was addressed by using the Cox-Snell residuals, which allowed us to identify the suitability of the new proposed mixture cure rate model.

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This paper aims to discuss the Bayesian estimation approach for the zero-inflated cure class of models, which extends the standard cure model by accommodating zero-inflated data in the survival analysis context. A comprehensive simulation study is carried out to assess the performance of the estimation procedure. A new estimation methodology is illustrated using a real dataset related to women diagnosed with invasive cervical cancer in Brazil.

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Abstract The aim of this study was to investigate the effect of preheating three bulk-fill and one conventional composite resin on the Vickers microhardness and depth of cure of these composites. In this study, three bulk-fill composites- SDR Plus (SDR), Estelite BULK FILL Flow (EST), Admira® Fusion x-tra (AFX), and one conventional composite resin G-ænial POSTERIOR (GP) were used as the control group. The samples were obtained at room temperature (24°C) and at 55°C in T2 mode after being placed in a heating device for 10 minutes. The samples were divided into eight groups (n=10) according to the type of material and heating process that was utilized (preheated and nonheated). All samples were tested with a Vickers microhardness (VHN) tester on the bottom and top surfaces. The first measurements were obtained at baseline; the second set of measurements was performed after the samples were stored in distilled water at 37°C for 24 hours. The depth of cure was calculated using a bottom/top hardness ratio of measurements. Statistical analysis was performed utilizing the SPSS V23 and Shapiro-Wilk tests. Lastly, the Duncan test was used for multiple comparisons (p<0.05). While the VHN increased after the preheating procedure in bulk-fill composites, it decreased in GP. There was no difference between the baseline and the 24-hour VHN values in SDR and GP. After 24 hours, while the VHN of EST increased, the VHN of AFX decreased. There was no difference between the hardness ratios of the AFX and EST samples (p<0.001) and hardness ratios were greater than GP and SDR. When comparing the baseline and the 24- hour values, the VHN depended on the type of materials. Sufficient curing depth was obtained in all groups with a thickness of 2mm.

Resumen El objetivo fue investigar el efecto del precalentamiento de tres resinas Bulk-fill, una resina compuesta convencional sobre la microdureza Vickers y la profundidad de curado de estas resinas. Se utilizaron tres composites Bulk-Fill-SDR Plus (SDR), Estelite BULK FILL Flow (EST), Admira® Fusion x-tra (AFX), y una resina compuesta convencional G-ænial POSTERIOR (GP) como grupo de control. Las muestras se obtuvieron a temperatura ambiente (24°C) y a 55°C en modo T2 después de haber sido colocadas en un dispositivo de calentamiento durante 10 minutos. Se dividieron en ocho grupos (n=10) según el tipo de material y el proceso de calentamiento que se utilizó (precalentado y no calentado). Se probaron con un medidor de microdureza Vickers (VHN) en las superficies inferior y superior. Las primeras mediciones se obtuvieron en la línea de base; la segunda se realizó después de que las muestras se almacenaran en agua destilada a 37°C durante 24 horas. La profundidad de curado se calculó utilizando una relación de dureza inferior/ superior de las mediciones. El análisis estadístico se realizó utilizando el SPSS V23 y las pruebas de Shapiro-Wilk. Por último, se utilizó la prueba de Duncan para las comparaciones múltiples (p<0,05). VHN aumentó tras el procedimiento de precalentamiento en las resina Bulk-Fill, disminuyó en los GP. No hubo diferencias entre los valores de VHN de referencia y de 24 horas en SDR y GP. Después de 24 horas, mientras que el VHN de EST aumentó, el VHN de AFX disminuyó. No hubo diferencias entre los ratios de dureza de las muestras de AFX y EST (p<0,001) y los ratios de dureza fueron mayores que los de GP y SDR. Al comparar los valores de referencia y los de 24 horas, el VHN dependió del tipo de materiales. Se obtuvo una profundidad de curado suficiente en todos los grupos con un grosor de 2mm.

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Canine cutaneous leishmaniasis (CCL) is an emerging zoonotic infection endemic in several countries of the world. Due to variable response to therapy and frequency of relapses, a more effective, safer, and inexpensive treatment is needed. Recently, it was reported that the hederagenin glucoside saponins (SS) and chromane-derived hydrazone (TC2) combined in a 1:1 ratio has high potential in antileishmanial therapy since both compounds alter the survival of Leishmania and the ability to infect adjacent macrophage. Not only the skin permeation and the absorption of an ointment containing 2% TC2 and 2% SS (w/w) was determined in this work, but also the acute dermal toxicity in both in vitro and in vivo assays. Last, the effectiveness and safety of the topical therapy with 2% TC2-2% SS ointment was evaluated in an observational study in dogs with diagnosis of cutaneous leishmaniasis (CL). Both TC2 and SS diffused through pig ear skin and traces of TC2 (but not SS) were detected in the stratum corneum of mice at 6-24 h. Neither TC2 nor SS was detected in plasma. The acute dermal toxicity was negative. Treatment with 2% TC2-2% SS ointment produced a complete long-term clinical cure in 56 dogs (24 females and 32 males) from the Orinoco and Amazonas regions in southeastern Colombia without adverse effects. All dogs have remained disease-free for the last 24 months. In conclusion, these results support the use of this topical therapy as a safer and new first-line local treatment of CCL that could help limit the spread of CL from dogs to humans.

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