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Endodontic microsurgery guided by navigation systems represents a precise and minimally invasive approach for retreatment of apical periodontitis following failed conventional endodontic therapy. Accurate localization and minimal access to the root apex are paramount for successful outcomes and preservation of anatomical structures. Workflow considerations, such as three-dimensional (3D) virtual planning and endodontic guidance represent new crucial aspects for addressing complex cases. This clinical case report presents the successful reintervention of a complex case using a Zekrya bur, operative microscopy, cone beam computed tomography and biocompatible materials. After a 48-month follow-up, complete healing of the treated area was observed. This minimally invasive technique, employing a simple instrument widely available globally, underscores the potential for efficient and predictable outcomes in complex endodontic microsurgical retreatment.

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This study evaluated the bone incorporation process of a screw-shaped internal fixation device made of poly (L-lactide-co-D, L-lactide) (PLDLLA). Thirty-two male Wistar rats received 32 fixation devices (2 mm × 6 mm) randomly assigned to either the right or left tibia and one implant in each animal. After 7, 14, 28, and 42 days, the rats were euthanized and the specimens were subjected to microtomographic computed tomography (microCT) and histomorphometric analyses to evaluate bone interface contact (BIC%) and new bone formation (NBF%) in cortical and cancellous bone areas. The animals euthanized on days 28 and 42 were treated with calcein and alizarin red, and confocal LASER microscopy was performed to determine the mineral apposition rate (MAR). Micro-CT revealed a higher percentage of bone volume (p < 0.006), trabecular separation (p < 0.001), and BIC in the cortical (p < 0.001) and cancellous (p = 0.003) areas at 28 and 42 days than at 7 and 14 days. The cortical NBF at 42 days was greater than that at 7 and 14 days (p = 0.022). No statistically significant differences were observed in cancellous NBF or MAR at 28 and 42 days. Based on these results, it can be seen that the PLDLLA internal fixation device is biocompatible and allows new bone formation around the screw thread.

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A 2-piece premanufactured glass-fiber post-and-core for a child with a severely compromised endodontically treated tooth to restore dental form, function, and esthetics, is described. A shorter chair time than for the conventional options was needed, and the post provided an adequate biomechanical response with a reduced intracanal cement thickness.

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Coralsnakes of the genus Micrurus are a diverse group of venomous snakes ranging from the southern United States to southern South America. Much uncertainty remains over the genus diversity, and understanding Micrurus systematics is of medical importance. In particular, the widespread Micrurus nigrocinctus spans from Mexico throughout Central America and into Colombia, with a number of described subspecies. This study provides new insights into the phylogenetic relationships within M. nigrocinctus by examining sequence data from a broad sampling of specimens from Mexico, Guatemala, Honduras, Nicaragua, Costa Rica, and Panama. The recovered phylogenetic relationships suggest that M. nigrocinctus is a species complex originating in the Pliocene and composed of at least three distinct species-level lineages. In addition, recovery of highly divergent clades supports the elevation of some currently recognized subspecies to the full species rank while others may require synonymization.

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In this work, we examined the action of two South American coralsnake (Micrurus corallinus and Micrurus dumerilii carinicauda) venoms on rat heart function in the absence and presence of treatment with Brazilian coralsnake antivenom (CAV) and varespladib (VPL), a potent phospholipase A2 inhibitor. Anesthetized male Wistar rats were injected with saline (control) or a single dose of venom (1.5 mg/kg, i.m.) and monitored for alterations in echocardiographic parameters, serum CK-MB levels and cardiac histomorphology, the latter using a combination of fractal dimension and histopathological methods. Neither of the venoms caused cardiac functional alterations 2 h after venom injection; however, M. corallinus venom caused tachycardia 2 h after venom injection, with CAV (given i.p. at an antivenom:venom ratio of 1:1.5, v/w), VPL (0.5 mg/kg, i.p.) and CAV + VPL preventing this increase. Both venoms increased the cardiac lesional score and serum CK-MB levels compared to saline-treated rats, but only the combination of CAV + VPL prevented these alterations, although VPL alone was able to attenuate the increase in CK-MB caused by M. corallinus venom. Micrurus corallinus venom increased the heart fractal dimension measurement, but none of the treatments prevented this alteration. In conclusion, M. corallinus and M. d. carinicauda venoms caused no major cardiac functional alterations at the dose tested, although M. corallinus venom caused transient tachycardia. Both venoms caused some cardiac morphological damage, as indicated by histomorphological analyses and the increase in circulating CK-MB levels. These alterations were consistently attenuated by a combination of CAV and VPL.

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In this work, we reported the efficacy of a combination of Brazilian therapeutic coralsnake antivenom (CAV) and varespladib (phospholipase A2 inhibitor - VPL) in partially neutralizing selected toxic effects of Micrurus dumerilii carinicauda coralsnake venom in rats. Venom caused local myonecrosis and systemic neurotoxicity, nephrotoxicity, and hepatotoxicity within 2 h of injection. CAV and VPL administered separately failed to prevent most of these alterations. However, a combination of CAV plus VPL offered variable protection against venom-induced coagulation disturbances, leukocytosis, and renal-hepatic morphological alterations.

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In this study, we investigated the action of varespladib (VPL) alone or in combination with a coral snake antivenom (CAV) on the local and systemic effects induced by Micrurus corallinus venom in rats. Adult male Wistar rats were exposed to venom (1.5 mg/kg - i.m.) and immediately treated with CAV (antivenom:venom ratio 1:1.5 'v/w' - i.p.), VPL (0.5 mg/kg - i.p.), or both of these treatments. The animals were monitored for 120 min and then anesthetized to collect blood samples used for haematological and serum biochemical analysis; after euthanasia, skeletal muscle, renal and hepatic tissue samples were collected for histopathological analysis. M. corallinus venom caused local oedema without subcutaneous haemorrhage or apparent necrosis formation, although there was accentuated muscle morphological damage; none of the treatments prevented oedema formation but the combination of CAV and VPL reduced venom-induced myonecrosis. Venom caused neuromuscular paralysis and respiratory impairment in approximately 60 min following envenomation; CAV alone did not prevent the neurotoxic action, whereas VPL alone prevented neurotoxic symptoms developing as did the combination of CAV and VPL. Venom induced significant increase of serum CK and AST release, mostly due to local and systemic myotoxicity, which was partially prevented by the combination of CAV and VPL. The release of hepatotoxic serum biomarkers (LDH and ALP) induced by M. corallinus venom was not prevented by CAV and VPL when individually administered; their combination effectively prevented ALP release. The venom-induced nephrotoxicity (increase in serum creatinine concentration) was prevented by all the treatments. VPL alone or in combination with CAV significantly prevented the venom-induced lymphocytosis. In conclusion, VPL shows to be effective at preventing the neurotoxic, nephrotoxic, and inflammatory activities of M. corallinus venom. In addition, VPL acts synergistically with antivenom to prevent a number of systemic effects caused by M. corallinus venom.

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The prognostic value of atrial thrombi (AT) among elective patients with atrial fibrillation (AF) referred for a rhythm control strategy is unclear. In this study, clinical variables were correlated with the presence of AT and long term survival among 205 patients submitted to transesophageal echocardiography before elective AF cardioversion or ablation. Atrial thrombi were present in 7.8% of cases and were significantly associated with reduced survival. Obesity was the only independent clinical predictor of AT [OR 4.27 (1.15-15.79), p = 0.03]. In patients with AF, AT appear to be associated with adverse outcomes, possibly indicating more advanced atrial cardiomyopathy.

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In this study, we examined the potential use of N-acetyl-L-cysteine (NAC) in association with a polyvalent antivenom and as stand-alone therapy to reduce the acute local and systemic effects induced by Lachesis muta muta venom in rats. Male Wistar rats (300-350 g) were exposed to L. m. muta venom (1.5 mg/kg - i.m.) and subsequently treated with anti-Bothrops/Lachesis serum (antivenom:venom ratio 1:3 'v/w' - i.p.) and NAC (150 mg/kg - i.p.) separately or in association; the animals were monitored for 120 min to assess changes in temperature, locomotor activity, local oedema formation and the prevalence of haemorrhaging. After this time, animals were anesthetized in order to collect blood samples through intracardiac puncture and then euthanized for collecting tissue samples; the hematological-biochemical and histopathological analyses were performed through conventional methods. L. m. muta venom produced pronounced local oedema, subcutaneous haemorrhage and myonecrosis, with both antivenom and NAC successfully reducing the extent of the myonecrotic lesion when individually administered; their association also prevented the occurrence of subcutaneous haemorrhage. Venom-induced creatine kinase (CK) release was significantly prevented by NAC alone or in combination with antivenom; NAC alone failed to reduce the release of hepatotoxic (alanine aminotransferase) and nephrotoxic (creatinine) serum biomarkers induced by L. m. muta venom. Venom induced significant increase of leucocytes which was also associated with an increase of neutrophils, eosinophils and monocytes; antivenom and NAC partially reduced these alterations, with NAC alone significantly preventing the increase of eosinophils whereas neither NAC or antivenom prevented the increase in monocytes. Venom did not induce changes in the erythrogram parameters. In the absence of a suitable antivenom, NAC has the potential to reduce a number of local and systemic effects caused by L. m. muta venom.

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In animal models, exposure to excess testosterone during gestation induces polycystic ovary syndrome (PCOS)-like reproductive and metabolic traits in female offspring, suggesting that the hyperandrogenemic intrauterine environment may have a role in the etiology of PCOS. Additionally, few studies have also addressed metabolic and reproductive outcomes in male offspring. In the present study, the intravenous glucose tolerance test (IGTT) was used to assess the insulin-glucose homeostasis at various ages during sexual development in male sheep born to testosterone-treated ewes. To further analyze the programming effect of testosterone on insulin-glucose homeostasis, indexes of insulin sensitivity were assessed in orchidectomized post-pubertal males born to testosterone-treated ewes (Torq-males) and orchidectomized post-puberal controls (Corq-males) before and 48 h after a testosterone injection. There was no difference in insulin sensitivity indexes between males born to testosterone-treated ewes (T-males) and control males born to control ewes (C-males) at 5, 10, 20 and 30 weeks of age, representing the infantile, early and late pre-pubertal, and early post-pubertal stage of sexual development, respectively. In orchidectomized males, basal levels of insulin and glucose were not different between both groups before and after the testosterone injection; however, Torq-males released more insulin before and after T challenge during the first 20 min of the test. Despite this, plasma glucose concentrations were not different in both groups during IVGTT, resulting in an insulin sensitivity index composite similar between groups. We concluded that the effect of prenatal exposure to excess testosterone may reprogram the pancreatic ß-cells insulin release in ovine males, with effects more evident in castrated males versus intact males.

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Varespladib (VPL) was primarily developed to treat inflammatory disturbances associated with high levels of serum phospholipase A2 (PLA2). VPL has also demonstrated to be a potential antivenom support agent to prevent PLA2-dependent effects produced by snake venoms. In this study, we examined the action of VPL on the coagulant, haemorrhagic and enzymatic activities of Lachesis muta rhombeata (South-American bushmaster) venom. Conventional colorimetric enzymatic assays were performed for PLA2, caseinolytic and esterasic activities; in vitro coagulant activities for prothrombin time (PT) and activated partial thromboplastin time (aPTT) were performed in rat citrated plasma through a quick timer coagulometer, whereas the dimensions of haemorrhagic haloes obtained after i.d. injections of venom in Wistar rats were determined using ImageJ software. Venom (1 mg/ml) exhibited accentuated enzymatic activities for proteases and PLA2 in vitro, with VPL abolishing the PLA2 activity from 0.01 mM; VPL did not affect caseinolytic and esterasic activities at any tested concentrations (0.001-1 mM). In rat citrated plasma in vitro, VPL (1 mM) alone efficiently prevented the venom (1 mg/ml)-induced procoagulant disorder associated to extrinsic (PT) pathway, whereas its association with a commercial antivenom successfully prevented changes in both intrinsic (aPTT) and extrinsic (PT) pathways; commercial antivenom by itself failed to avoid the procoagulant disorders by this venom. Venom (0.5 mg/kg)-induced hemorrhagic activity was slightly reduced by VPL (1 mM) alone or combined with antivenom (antivenom:venom ratio 1:3 'v/w') in rats, with antivenom alone producing no protective action on this parameter. In conclusion, VPL does not inhibit other major enzymatic groups of L. m. rhombeata venom, with its high PLA2 antagonize activity efficaciously preventing the venom-induced coagulation disturbances.

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BACKGROUND: Studies with integrative approaches (based on different lines of evidence) are fundamental for understanding the diversity of organisms. Different data sources can improve the understanding of the taxonomy and evolution of snakes. We used this integrative approach to verify the taxonomic status of Hydrodynastes gigas (Duméril, Bibron & Duméril, 1854), given its wide distribution throughout South America, including the validity of the recently described Hydrodynastes melanogigas Franco, Fernandes & Bentim, 2007. METHODS: We performed a phylogenetic analysis of Bayesian Inference with mtDNA 16S and Cytb, and nuDNA Cmos and NT3 concatenated (1,902 bp). In addition, we performed traditional morphometric analyses, meristic, hemipenis morphology and coloration pattern of H. gigas and H. melanogigas. RESULTS: According to molecular and morphological characters, H. gigas is widely distributed throughout South America. We found no evidence to support that H. gigas and H. melanogigas species are distinct lineages, therefore, H. melanogigas is a junior synonym of H. gigas. Thus, the melanic pattern of H. melanogigas is the result of a polymorphism of H. gigas. Melanic populations of H. gigas can be found in the Tocantins-Araguaia basin.

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OBJECTIVES: Controversy exists about whether the elastic modulus (E) mismatch between the loading indenter and ceramic materials influences fatigue testing results. The research hypotheses were that for porcelain veneered Y-TZP crowns 1) A low modulus Steatite indenter (SB) leads to higher fatigue reliability compared to a high modulus tungsten carbide indenter (WC); 2) Different surface damage patterns are expected between low and high modulus indenters after sliding contact fatigue testing. All ceramic crowns will exhibit similar step-stress accelerated life testing (SSALT) contact fatigue reliability (hypothesis 1) and failure characteristics (hypothesis 2) when using high stiffness tungsten carbide (WC, E = 600 GPa) vs. enamel like steatite (SB, E = 90 GPa) indenters. METHODS: Manufacturer (3M Oral Care) prepared Y-TZP-veneered all-ceramic molar crowns were bonded to aged resin composite reproductions of a standard tooth preparation and subjected to mouth-motion SSALT fatigue (n = 18 per indenter type). Failure was defined either as initial inner cone crack (IC), or final fracture (FF) when porcelain fractured (chipping). Selected IC specimens that did not progress to FF were embedded in epoxy resin and sectioned for fractographic analysis. RESULTS: The distribution of failures across the load and cycle profiles lead to similar calculated Weibull Use Level Probability Plots with overlap of the 2-sided 90% confidence bounds. The calculated reliability for IC and FF was equivalent at a mission of 300 N or 700 N load and 50,000 cycles, although the WC indenter had a trend for lower reliability for IC at 700 N. Both indenters produced similar patterns of wear and cracking on crown surfaces. Fractographic landmarks showed competing failure modes, but sliding contact partial inner cone cracks were the most dominant for both groups. SIGNIFICANCE: The more compliant Steatite indenter had similar veneered crown fatigue reliability and failure modes to those found with use of a high stiffness tungsten carbide indenter (hypotheses 1 and 2 rejected).

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Plastic is an allochthonous material to marine ecosystems but is rapidly colonized by marine microbial communities, with an as yet unclear contribution to biogeochemical cycles. In this study, we investigated the influence of an active microbial community grown on microplastic particles (the plastisphere) on CO2 and N2O recycling and its potential role in greenhouse gas inventories and air-sea exchange. Microplastics were collected during two cruises (Cimar 21 and FIP Montes Submarinos) from the surface layer (5 m depth) from several contrasting trophic regions of the South Pacific Ocean, i.e., from a transition zone off the eutrophic coastal upwelling of Chile, to a mesotrophic transition area of oceanic seamounts and, finally, to an oligotrophic zone in the South Pacific Subtropical Gyre. . Experiments were carried out onboard to evaluate CO2 and N2O production/consumption by the plastisphere. The active microbial community and its specific quantification were determined for Cimar 21 using iTag 16 S rRNA. The experiments showed that the plastisphere generally contributed to CO2 and N2O production/consumption, with rates ranging from -20.5 (consumption) to +4.5 (production) µmol/m2/d. The seamounts and the transition zone presented the highest production/consumption rates. The experiments performed in the two seamount stations showed that production and consumption of CO2 were related to the environmental nutrient concentration. Both stations presented N2O consumption that was associated with the high nitrogen deficit of the subantarctic water mass. The transition zone presented CO2 and N2O production in a plastisphere dominated by heterotrophic communities. The plastisphere in oligotrophic waters was diverse and active. The experiments, however, presented low or no production of greenhouse gases. Our results show a contribution of CO2 and N2O to the global gas surface inventories and air-sea exchange is lower than 1% of the global sources. These results highlight different critical impacts of plastic pollution on the environment that have, until now, not been considered.

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Different restorative techniques have been proposed for the treatment of posterior teeth affected by cracked tooth syndrome (CTS). However, the literature is scarce in protocols of how to solve CTS using ceramic restorations made by computer aided design-computer aided manufacturing (CAD-CAM) system. CAD-CAM provides a fast and efficient restorative treatment usually in a single visit, reducing the risk of contamination and micro-infiltration of the cracked line. The objective of this work was to describe 3 clinical cases of cracked teeth, which presented vertical fracture lines in different directions and extension through the pulp, restored by CAD-CAM system, with 5-year follow-up. Patients with short-term spontaneous masticatory pain, cold sensibility and restored teeth without cuspal coverage were selected. Digital radiographs (DR) were taken to confirm the pulp and periapical status. Periodontal probing depth, sensitivity, percussion, and occlusion tests were performed. The fracture lines with their direction and extension were identified under dental optical microscope (DOM). The treatment plan was performed in two stages: immediate treatment to stabilize the tooth and minimize pain, and final restorative treatment by CAD-CAM system to stabilize the crack. Patients were between the ages of 37 and 45 years. Most of the studied teeth presented extensive restorations without cuspal coverage. The presence of occlusal interference, in lateral movement, was a constant finding. Endodontic treatment was performed in cases of irreversible pulpitis or pulpal necrosis. In all three cases, cavity preparation was performed for full coverage restorations, as the fracture lines extended in several directions, requiring a re-enforcement of the cervical region of the teeth in question. The survival rate of the reported cases was 100% with 5-year clinical and radiographic follow-up, suggesting that CAD-CAM system may be a promising alternative treatment in the management of CTS, improving tooth longevity.

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ABSTRACT This study goal is to present a case report of tooth bleaching treatment with the combination of the custom tray and in-office techniques, and to discuss about the considerations for result maintenance. A treatment approach was planned involving exogenous bleaching with custom trays with 7.5% hydrogen peroxide, and in-office bleaching with 35% hydrogen peroxide. The in-office bleaching agent was applied in two 15-minute applications, without led light. The patient was instructed to use the custom trays only a day after, with one drop of the bleaching agent for each tooth space. After the application of the bleaching agent, the patient used the trays for 1 hour per day, continuously for 30 days, 15 days for each arch. Considering the executed treatment approach, we may conclude that when correctly indicated, tooth bleaching with the combination of the in-office and custom trays techniques can be an acceptable choice of treatment, capable of enhancing the smile esthetics with a simple technique that preserves the sound dental structure. The patient should be instructed for the maximum color preservation and esthetic result maintenance, and should be advised that retreatments may become necessary depending on the oral hygiene and frequence of coloured food and drinks intake.

RESUMO O objetivo deste estudo é apresentar um relato de caso em que foi realizado o clareamento dentário com a combinação das técnicas de consultório e de moldeiras e discutir sobre considerações para a manutenção do resultado. Um plano de tratamento foi proposto envolvendo clareamento exógeno com moldeiras com peróxido de hidrogênio 7,5% e o clareamento em consultório com peróxido de hidrogênio 35%. O gel clareador de clareamento em consultório foi aplicado 2 vezes, por 15 minutos cada aplicação, sem luz do tipo Led. A paciente foi orientada a usar as moldeiras customizadas para o clareamento caseiro apenas a partir do dia seguinte, sendo uma gota de gel clareador no espaço equivalente a cada dente. Após a dosagem do gel, ela usou as moldeiras por 1 hora por dia, ininterruptamente por 30 dias, sendo 15 dias para cada arco. Diante do planejamento e terapia executados no caso clínico apresentado, pode-se concluir que a técnica clareadora utilizando a combinação de clareamento em consultório e clareamento com moldeiras customizadas, quando corretamente indicada, pode ser considerada uma alternativa de tratamento bastante satisfatória por ser uma técnica simples capaz de melhorar a estética do sorriso preservando a estrutura dental hígida. O paciente deve ser orientado para a máxima preservação da cor e manutenção estética alcançada, e deve ser ressaltado que retratamentos podem ser necessários dependendo da higiene oral e da frequência de ingestão de alimentos e bebidas corantes.

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RESUMO Objetivo Identificar os cuidados concebidos como boas práticas de enfermagem a pacientes em ventilação mecânica invasiva no contexto de emergência hospitalar. Método Estudo descritivo, qualitativo, realizado de junho a setembro de 2017. Participaram 16 enfermeiros da emergência geral de um hospital da região Sul do Brasil. Os cuidados, extraídos da literatura e classificados quanto ao nível de evidência, foram agrupados em categorias por similaridade e selecionados nos Grupos de Discussão. Resultados Os enfermeiros consideraram como boas práticas aos pacientes em ventilação mecânica invasiva um total de 13 cuidados, os quais estão relacionados ao tubo endotraqueal, ao ventilador e circuito, à prevenção de broncoaspiração, ao controle de infecção e à sedação, analgesia/sono, vigília/dor. Os cuidados foram extraídos de estudos com níveis de evidência IIb, IV e VI. Conclusão e implicações para a prática As boas práticas de enfermagem em ventilação mecânica invasiva, concebidas pelos enfermeiros da emergência, respaldam cientificamente a assistência ao paciente em suporte ventilatório invasivo, podendo ser aplicadas em contextos similares.

RESUMEN Objetivo Identificar los cuidados concebidos como buenas prácticas de enfermería a pacientes en ventilación mecánica invasiva en el contexto de emergencia hospitalaria. Método Estudio descriptivo, cualitativo, realizado entre junio y septiembre de 2017. Participaron 16 enfermeros de la emergencia general de un hospital de la región Sur de Brasil. Los cuidados, extraídos de la literatura y clasificados según el nivel de evidencia, se agruparon en categorías por similitud y seleccionados en los grupos de discusión. Resultados Los enfermeros consideraron como buenas prácticas para pacientes con ventilación mecánica invasiva un total de 13 cuidados, relacionados con el tubo endotraqueal, el ventilador y circuito, la prevención de la broncoaspiración, el control de infección y la sedación, la analgesia/el sueño, la vigilia/dolor. Los cuidados fueron extraídos de estudios con niveles de evidencia IIb, IV y VI. Conclusión e implicaciones para la práctica Las buenas prácticas de enfermería en ventilación mecánica invasiva, concebidas por enfermeros de emergencia, respaldan científicamente la atención al paciente con asistencia respiratoria invasiva y pueden aplicarse en contextos similares.

ABSTRACT Objective To identify care conceived as good nursing practices for patients on invasive mechanical ventilation in the context of hospital emergency. Method Descriptive, qualitative study, conducted from June to September 2017 with the participation of 16 nurses from general emergency room of a hospital in Brazil's southern region. Care, extracted from the literature and classified according to evidence level, were grouped into categories by similarity and selected in Discussion Groups. Results The nurses considered a total of 13 care measures as good practices for the patients on mechanical ventilation. These care measures are related to endotracheal tube, ventilator and circuit, prevention of bronchoaspiration, infection control and sedation, analgesia/sleep, wakefulness/pain. Practices were extracted from studies with evidence levels IIb, IV and VI. Conclusion and implications for practice Good nursing practices related to invasive mechanical ventilation, as conceived by nurses from the emergency room, scientifically supportive care towards patients on invasive ventilatory support and may be applied in similar contexts.

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