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BACKGROUND AND OBJECTIVES: Prior research has shown that temporary deferrals negatively influence donor return rates, but it remains unknown the extent to which these effects vary across reasons for deferral. We investigate whether deferrals differ in their degree of perceived stigmatization and, if so, how being deferred for stigmatizing (vs. non-stigmatizing) reasons affects subsequent donation behaviour. MATERIALS AND METHODS: We examined whether reasons for deferral vary on their perceived level of stigmatization through an online survey (n = 400). Furthermore, we used a dataset encompassing 25 years of donation records from the state-run blood collection agency (BCA) from Rio de Janeiro, Brazil, to investigate how stigmatizing (vs. non-stigmatizing) reasons for deferral affected return rates of 82,648 donors over a 60-month follow-up period. RESULTS: Being deferred for sex- and drug-related reasons was perceived as much more stigmatizing than other reasons for deferral (odds ratio = 3.14, 95% confidence interval [CI]: 2.33-4.25). Controlling for multiple observables, prospective donors were less likely to return to the BCA when deferred for stigmatizing (vs. non-stigmatizing) reasons (adjusted hazard ratio = 0.87, 95% CI: 0.83-0.93). CONCLUSION: Donors perceive deferrals motivated by sex- and drug-related reasons as particularly stigmatizing, which is negatively associated with donor return rates. BCAs may want to pay special attention when communicating stigmatizing reasons for deferral to prospective donors.
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Donantes de Sangre , Humanos , Brasil , Donantes de Sangre/psicología , Masculino , Femenino , Adulto , Encuestas y Cuestionarios , Persona de Mediana Edad , EstereotipoRESUMEN
AIM: The present study investigated the influence of apical periodontitis (AP) on the severity of rheumatoid arthritis (RA) using a Wistar rat model. METHODOLOGY: Forty male Wistar rats were distributed across four groups (n = 10) based on the induction of RA and AP: Control, RA, AP, and RA + AP. RA was induced through two immunisations with type II collagen emulsified in incomplete Freund's adjuvant, followed by one immunisation with complete Freund's adjuvant. After 21 days of RA induction, AP was induced by exposing the pulp of four molars. Animals were euthanized after 28 days of pulp exposure. Through the experiment, visual and behavioural assessments tracked RA development and the knees and hind paw joints were measured. Micro-computed tomography scans of knees and hind paws, as well as mandibles and maxillae, were conducted to evaluate RA severity and the presence of AP, respectively. Serum samples were collected to analyse proinflammatory cytokines (IL-1ß, IL-2, IL-17, and TNF-α). Non-parametric data were analysed using the Kruskal-Wallis test followed by Student-Newman-Keuls test, while one-way anova followed by Tukey's test was performed for parametric data. A significance level of 5% was employed. RESULTS: All molars submitted to access cavity developed AP. All joints subjected to arthritis induction developed the disease, with AP + RA demonstrating a higher arthritis severity when compared to the RA group (p < .05). RA + AP group displayed a significantly larger hind paw and knee circumference compared to the RA group (p < .05). Micro-CT images of RA and RA + AP groups revealed joints with erosions and bone deformities, with a significantly lower bone surface density, lower trabecular number and higher trabecular separation in the hind paw and a significantly lower percent bone volume and higher trabecular separation in the knees of RA + AP group compared to RA group (p < .05). RA + AP group exhibited a significantly higher level of TNF-α and a lower level of IL-2 compared to all other groups (p < .05). Both RA and RA + AP groups had significantly higher IL-17 levels (p < .05), while there was no significant difference in IL-1ß levels among the groups (p > .05). CONCLUSION: The findings from this study underscore a possible relationship between apical periodontitis and the exacerbation of rheumatoid arthritis.
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Artritis Reumatoide , Modelos Animales de Enfermedad , Periodontitis Periapical , Ratas Wistar , Microtomografía por Rayos X , Animales , Masculino , Periodontitis Periapical/diagnóstico por imagen , Periodontitis Periapical/patología , Ratas , Índice de Severidad de la Enfermedad , Factor de Necrosis Tumoral alfa/sangre , Citocinas/metabolismo , Artritis Experimental/patología , Artritis Experimental/diagnóstico por imagen , Interleucina-1beta/sangre , Interleucina-2/sangre , Interleucina-17RESUMEN
The effects of normal (NA) and controlled atmosphere (CA) storage and postharvest treatment with 1-methylcyclopropene (1-MCP) before CA storage for 5 months on the volatilome, biochemical composition and quality of 'Golden Delicious' (GD) and 'Red Delicious' (RD) apples were studied. Apples stored under NA and CA maintained and 1-MCP treatment increased firmness in both cultivars. NA storage resulted in a decrease of glucose, sucrose and fructose levels in both cultivars. When compared to CA storage, 1-MCP treatment caused a more significant decrease in sucrose levels and an increase in glucose levels. Additionally, 1-MCP-treated apples exhibited a significant decrease in malic acid content for both cultivars. All storage conditions led to significant changes in the abundance and composition of the volatilome in both cultivars. GD and RD apples responded differently to 1-MCP treatment compared to CA storage; higher abundance of hexanoate esters and (E,E)-α-farnesene was observed in RD apples treated with 1-MCP. While 1-MCP was effective in reducing (E,E)-α-farnesene abundance in GD apples, its impact on RD apples was more limited. However, for both cultivars, all storage conditions resulted in lower levels of 2-methylbutyl acetate, butyl acetate and hexyl acetate. The effectiveness of 1-MCP is cultivar dependent, with GD showing better results than RD.
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Almacenamiento de Alimentos , Malus , Malus/química , Malus/metabolismo , Ciclopropanos/farmacología , Compuestos Orgánicos Volátiles/análisis , Compuestos Orgánicos Volátiles/química , Frutas/química , Frutas/metabolismo , Sacarosa/metabolismo , Malatos , Sesquiterpenos/análisis , Glucosa/metabolismo , Fructosa/metabolismo , Fructosa/análisisRESUMEN
Matrix vesicles are a special class of extracellular vesicles thought to actively contribute to both physiologic and pathologic mineralization. Proteomic studies have shown that matrix vesicles possess high amounts of annexin A5, suggesting that the protein might have multiple roles at the sites of calcification. Currently, Annexin A5 is thought to promote the nucleation of apatitic minerals close to the inner leaflet of the matrix vesicles' membrane enriched in phosphatidylserine and Ca2+. Herein, we aimed at unravelling a possible additional role of annexin A5 by investigating the ability of annexin A5 to adsorb on matrix-vesicle biomimetic liposomes and Langmuir monolayers made of dipalmitoylphosphatidylserine (DPPS) and dipalmitoylphosphatidylcholine (DPPC) in the absence and in the presence of Ca2+. Differential scanning calorimetry and dynamic light scattering measurements showed that Ca2+ at concentrations in the 0.5-2.0 mM range induced the aggregation of liposomes probably due to the formation of DPPS-enriched domains. However, annexin A5 avoided the aggregation of liposomes at Ca2+ concentrations lower than 1.0 mM. Surface pressure versus surface area isotherms showed that the adsorption of annexin A5 on the monolayers made of a mixture of DPPC and DPPS led to a reduction in the area of excess compared to the theoretical values, which confirmed that the protein favored attractive interactions among the membrane lipids. The stabilization of the lipid membranes by annexin A5 was also validated by recording the changes with time of the surface pressure. Finally, fluorescence microscopy images of lipid monolayers revealed the formation of spherical lipid-condensed domains that became unshaped and larger in the presence of annexin A5. Our data support the model that annexin A5 in matrix vesicles is recruited at the membrane sites enriched in phosphatidylserine and Ca2+ not only to contribute to the intraluminal mineral formation but also to stabilize the vesicles' membrane and prevent its premature rupture.
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Anexinas , Liposomas , Anexina A5/química , Anexina A5/metabolismo , Fosfatidilserinas/química , Fosfatidilserinas/metabolismo , Biomimética , Proteómica , Calcio/metabolismoRESUMEN
BACKGROUND: The results of vital pulp treatments in permanent teeth have been encouraging. Currently, pulpotomy treatment for permanent teeth primarily utilizes mineral trioxide aggregate (MTA) as the dressing material, followed by calcium hydroxide. While other calcium-silicate-based cements have been suggested for pulpotomy, there is a limited number of studies evaluating their long-term effectiveness. OBJECTIVES: The objective of this systematic review and meta-analysis was to evaluate the success rate of pulpotomies performed on permanent teeth, comparing the use of ProRoot MTA with that of calcium hydroxide and other bioceramic materials. METHODS: A comprehensive search was conducted in several electronic databases, including PubMed, Cochrane Library, Scopus, Web of Science, Embase and Science Direct until December 2022. The search was guided by PICOS criteria, including only randomized clinical trials (RCTs) that evaluated the success rate of pulpotomy treatments in permanent teeth using ProRoot MTA in comparison to calcium hydroxide and other bioceramic materials. The quality of the included studies was assessed using the RoB-2 tool to evaluate the risk of bias, and relevant data were extracted and analysed in RevMan software 5.3 using fixed-effect models. The GRADE tool was used to determine the overall quality of evidence. RESULTS: The initial search retrieved 1072 studies and, after eliminating duplicates, 677 studies were screened and 28 studies were considered for eligibility. In the final selection process, 16 studies were included in the systematic review, with 10 being determined as having a high risk of bias. Pulpotomy showed an overall mean success rate of 92% after 1 year. The meta-analysis indicated a significantly higher success rate for pulpotomies utilizing MTA in comparison with calcium hydroxide, while no significant difference was seen between MTA and calcium-enriched mixture (CEM) or Biodentine. The GRADE assessment revealed an overall low level of evidence for the included studies. DISCUSSION: Most randomized controlled trials exhibited a significant absence of control over confounding factors. CONCLUSIONS: This systematic review and meta-analysis demonstrate that pulpotomy is a highly effective treatment for managing permanent teeth. The results indicate that the success rate of pulpotomy using ProRoot MTA is significantly higher than when using calcium hydroxide. However, the certainty of evidence supporting these findings is low, and there is a need for well-designed RCTs to assess the long-term outcomes of pulpotomy using newer bioceramic materials. REGISTRATION: This systematic review was registered in the PROSPERO database (registration number CRD42023393970).
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Hidróxido de Calcio , Pulpotomía , Humanos , Hidróxido de Calcio/uso terapéutico , Pulpotomía/métodos , Calcio , Compuestos de Aluminio/uso terapéutico , Combinación de Medicamentos , Óxidos/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto , Compuestos de Calcio/uso terapéutico , Resultado del Tratamiento , Silicatos/uso terapéuticoRESUMEN
AIM: This study aimed to evaluate the volumetric change of root canal sealers through micro-computed tomographic analysis using a novel in vivo model and to compare the results with those obtained using an ex vivo test. METHODOLOGY: Eighteen single-rooted teeth were cut to 5 mm length from the root apex. The root canals were uniformly enlarged and filled with EndoSequence BC Sealer or AH Plus Jet root canal sealers. Samples were stored at 37°C and 95% relative humidity for 24 h and then scanned with a micro-CT device. Twelve samples (n = 6 for each sealer) were implanted in the subcutaneous tissue of Wistar rats, while six samples (n = 3 for each sealer) were immersed in 20 mL of phosphate-buffered saline (PBS) at 37°C at neutral pH. After 7 and 30 days, teeth were removed from subcutaneous tissue or PBS and rescanned. Statistical analysis of volume changes was performed using Shapiro-Wilk's test and independent t-test (p < .05). RESULTS: AH Plus Jet had smaller volume changes (-2.2 to +0.77%) than EndoSequence BC Sealer (-2.0 to +4.0%) (p < .05), in the two tested models. The volume of the root canal sealers decreased over time (p < .05), in vivo. AH Plus Jet results varied between the in vivo and ex vivo results (p < .05), while EndoSequence BC Sealer presented similar volume losses for both experimental models (p > .05). CONCLUSION: EndoSequence BC Sealer lost more volume than AH Plus Jet. The experimental conditions influenced the volumetric change of AH Plus Jet but not the EndoSequence BC Sealer. The ex vivo model should be further explored as a methodological alternative to assess the volumetric changes of root canal sealers without causing harm to animals.
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Materiales de Obturación del Conducto Radicular , Ratas , Animales , Resinas Epoxi , Cavidad Pulpar , Ratas Wistar , Concentración de Iones de Hidrógeno , Silicatos , Ensayo de MaterialesRESUMEN
BACKGROUND: Previous studies that describe the negative association between temporary deferrals and donor return rates commonly come from settings where mechanisms are in place to win back lapsing donors. There is little evidence on the size and prevalence of this negative association in settings with no such retention activities. STUDY DESIGN AND METHODS: We use data from more than 2 million donation attempts made at a blood collection agency in Brazil over a 26-year period. We describe the distribution of deferrals across donor demographic and behavioral characteristics, and estimate multivariate survival analysis models with matched samples to measure the impact of deferrals on return rates. We control for sex, race, age, education, donation type, number of previous attempts, previous donations, and previous deferrals. We test for heterogeneous effects in interaction models with selected donor demographic and behavioral characteristics. RESULTS: Temporary deferrals were associated with a 50% decrease in the likelihood of return. Although the effect was observed for all population subgroups and across the full length of the dataset, it varied in magnitude. The influence of deferrals was more negative among older donors and those reporting replacement motives, and less negative among more educated donors and those with a previous donation. DISCUSSION: We found that temporary deferrals meaningfully harm donor careers in a setting where specific retention activities are absent. Although the effects are widespread across the population and persistent in time, there are also heterogeneities, which must be considered when designing interventions targeted at wining-back specific groups of deferred donors.
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Donantes de Sangre , Motivación , Brasil , Humanos , Análisis Multivariante , PrevalenciaRESUMEN
Bone biomineralization is an exquisite process by which a hierarchically organized mineral matrix is formed. Growing evidence has uncovered the involvement of one class of extracellular vesicles, named matrix vesicles (MVs), in the formation and delivery of the first mineral nuclei to direct collagen mineralization. MVs are released by mineralization-competent cells equipped with a specific biochemical machinery to initiate mineral formation. However, little is known about the mechanisms by which MVs can trigger this process. Here, we present a combination of in situ investigations and ex vivo analysis of MVs extracted from growing-femurs of chicken embryos to investigate the role played by phosphatidylserine (PS) in the formation of mineral nuclei. By using self-assembled Langmuir monolayers, we reconstructed the nucleation core - a PS-enriched motif thought to trigger mineral formation in the lumen of MVs. In situ infrared spectroscopy of Langmuir monolayers and ex situ analysis by transmission electron microscopy evidenced that mineralization was achieved in supersaturated solutions only when PS was present. PS nucleated amorphous calcium phosphate that converted into biomimetic apatite. By using monolayers containing lipids extracted from native MVs, mineral formation was also evidenced in a manner that resembles the artificial PS-enriched monolayers. PS-enrichment in lipid monolayers creates nanodomains for local increase of supersaturation, leading to the nucleation of ACP at the interface through a multistep process. We posited that PS-mediated nucleation could be a predominant mechanism to produce the very first mineral nuclei during MV-driven bone/cartilage biomineralization.
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Biomineralización/fisiología , Fosfatos de Calcio/metabolismo , Lípidos/fisiología , Fosfatidilserinas/metabolismo , Animales , Apatitas/metabolismo , Biomimética/métodos , Calcificación Fisiológica/fisiología , Calcio/metabolismo , Cartílago/metabolismo , Pollos , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Vesículas Extracelulares/metabolismo , Fémur/metabolismo , Microscopía Electrónica de Transmisión/métodosRESUMEN
The mechanisms driving pathological beta-amyloid (Aß) generation in late-onset Alzheimer's disease (AD) are unclear. Two late-onset AD risk factors, Bin1 and CD2AP, are regulators of endocytic trafficking, but it is unclear how their endocytic function regulates Aß generation in neurons. We identify a novel neuron-specific polarisation of Aß generation controlled by Bin1 and CD2AP We discover that Bin1 and CD2AP control Aß generation in axonal and dendritic early endosomes, respectively. Both Bin1 loss of function and CD2AP loss of function raise Aß generation by increasing APP and BACE1 convergence in early endosomes, however via distinct sorting events. When Bin1 levels are reduced, BACE1 is trapped in tubules of early endosomes and fails to recycle in axons. When CD2AP levels are reduced, APP is trapped at the limiting membrane of early endosomes and fails to be sorted for degradation in dendrites. Hence, Bin1 and CD2AP keep APP and BACE1 apart in early endosomes by distinct mechanisms in axon and dendrites. Individuals carrying variants of either factor would slowly accumulate Aß in neurons increasing the risk for late-onset AD.
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Proteínas Adaptadoras Transductoras de Señales/metabolismo , Péptidos beta-Amiloides/metabolismo , Proteínas del Citoesqueleto/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Animales , Ácido Aspártico Endopeptidasas/metabolismo , Axones/metabolismo , Membrana Celular/metabolismo , Endocitosis , Endosomas , Femenino , Regulación de la Expresión Génica , Técnicas de Silenciamiento del Gen , Masculino , Ratones , Proteínas del Tejido Nervioso/genética , Neuronas/metabolismo , Transporte de Proteínas , Proteínas Supresoras de Tumor/genéticaRESUMEN
OBJECTIVE: To assess the short- and long-term effectiveness of a lottery incentive intervention to promote the purchase of healthy products in school cafeterias. DESIGN: A quasi-experiment in which students' purchases in intervention schools were analysed in a pre-post analysis and also compared with a control school in a difference-in-differences model. A hierarchical linear model assessed the mean number of promoted healthy products purchased daily per participant before (twenty-six weekdays), during (nine weekdays) and after (twenty-eight weekdays) the intervention period. Sex, age and prior purchasing behaviour served as covariates. SETTING: Convenience sample of school cafeterias using a debit-card payment method that allowed for the assessment of students' purchasing behaviour.ParticipantsStudents who used the pre-paid card to buy snacks at the school cafeteria. A total of 352 students (208 in intervention schools and 144 in control school) were included in the final analyses. RESULTS: The incentives programme significantly increased the purchase of promoted healthy products during (v. before) the intervention period in intervention schools (P<0·001), especially among younger children (P=0·036). Among the students who purchased the promoted healthier products during the intervention, there was an increase in total number of purchased products (healthy non-promoted, but also of less healthy products). Sex and past consumption behaviour did not influence the response to incentives in the short term. On average, no long-term effect was observed. CONCLUSIONS: Long-term and negative spillover effects must be taken into consideration for a complete understanding of the effects of incentives on healthier eating.
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Dieta Saludable , Conducta Alimentaria , Promoción de la Salud , Instituciones Académicas , Brasil , Niño , Comportamiento del Consumidor , Femenino , Servicios de Alimentación , Conductas Relacionadas con la Salud , Humanos , Masculino , EstudiantesRESUMEN
A pentafluorobenzamide stationary phase was synthesized by an easy method with no intermediate purification steps. Physicochemical characterization (elemental analysis, fourier transform infrared spectroscopy, 29 Si and 13 C nuclear magnetic resonance spectroscopy) confirmed the presence of pentafluorobenzamide functionalization on the surface of the silica particles. The pentafluorobenzamide stationary phase proved to be quite versatile as it can be used in two different modes in liquid chromatography: reversed phase and hydrophilic interaction liquid chromatography. Chromatographic characterizations in both modes confirmed the multiple interactions established by the new stationary phase, such as hydrogen bonding and π-π and ion-exchange interactions. The pentafluorobenzamide stationary phase was successfully employed for the separation of nucleosides and antihypertensive drugs under hydrophilic interaction liquid chromatography conditions, as well as pesticides and benzodiazepine using reversed phase conditions. The stationary phase showed significant potential when compared with commercial columns.
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This study addresses the challenge of low blood donation rates in developing countries by examining the effectiveness of a barrier-removal incentive-a one-day transportation voucher-to promote blood donation. Utilizing a longitudinal dataset of 23,750 donors from a Brazilian blood collection agency (BCA) collected between March 2018 and May 2020, we examine the short and long-term effects of this campaign on donation rates. Our results show that the incentive had a large positive influence on both donation attempts and successful donations on the day of the campaign. However, the short-term success of the intervention had an unintended consequence: the significant increase in prospective donors' waiting time at the BCA during the intervention day, which may help explain the negative impact on return rates in the 24-month follow-up. Despite these opposing outcomes, the net effect of the one-day blood donation incentive was still positive, offering valuable insights for BCAs aiming to enhance donor recruitment and retention strategies and emphasizing the need to balance immediate benefits with potential long-term impacts.
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Donantes de Sangre , Motivación , Humanos , Donantes de Sangre/psicología , Donantes de Sangre/estadística & datos numéricos , Masculino , Femenino , Adulto , Brasil , Persona de Mediana Edad , Estudios Longitudinales , Conducta SocialRESUMEN
Bats are the second most diverse order of mammals and play a central role in ecosystem dynamics. They are also important reservoirs of potentially zoonotic microorganisms, of which rabies virus is the most lethal among the bat-transmitted zoonotic pathogens. Importantly, recent outbreaks of human rabies have been reported from the Brazilian Amazon. Here we present a survey of bat species and rabies virus (RABV) circulation in a bat assemblage in the Marajó region, northern Brazil. Using data from mist-net captures and bioacoustic sampling, 56 bat species were recorded along the Jacundá River basin over a 10-day expedition in November 2022. For the investigation of RABV, we used the direct fluorescent antibody test (DFAT) and the rapid fluorescent focus inhibition test (RFFIT). In total, 159 bat individuals from 22 species were investigated for RABV. Five adults of the common vampire bat, Desmodus rotundus, showed RABV-specific antibodies in serum samples. Additionally, we report on local residents with injuries caused by D. rotundus bites and the occurrence of colonies of non-hematophagous bats from different species roosting inside human residences. This scenario raises concerns about the risks of new cases of human rabies and other zoonotic diseases associated with bats in the region and highlights the need for epidemiological surveillance and mitigation measures to prevent outbreaks of emerging infectious diseases.
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Anticuerpos Antivirales , Quirópteros , Brotes de Enfermedades , Virus de la Rabia , Rabia , Zoonosis , Quirópteros/virología , Animales , Brasil/epidemiología , Virus de la Rabia/inmunología , Virus de la Rabia/aislamiento & purificación , Virus de la Rabia/clasificación , Rabia/epidemiología , Rabia/veterinaria , Rabia/virología , Humanos , Zoonosis/epidemiología , Zoonosis/virología , Anticuerpos Antivirales/sangre , Femenino , Masculino , Adulto , Persona de Mediana Edad , AdolescenteRESUMEN
Introduction: To assess the methodological quality of systematic reviews (SRs) that evaluated the association between apical periodontitis (AP) and chronic diseases. Materials and Methods: A systematic search was performed in the databases PubMed, Virtual Health Library, Scopus, Cochrane Library, Embase, Web of Science and Open Grey. SRs that evaluated the association between any chronic disease and AP, and that had performed a valid risk of bias assessment were included. The AMSTAR-2 tool was used for quality assessment and each included systematic review received a final categorization as having "high", "moderate", "low", or "critically low" quality. Results: Nine studies that met the eligibility criteria were included. The diseases investigated were cardiovascular diseases, diabetes mellitus, HIV, osteoporosis, chronic liver disease, blood disorders and autoimmune diseases. The systematic reviews included in this umbrella review showed a 'low' to 'high' quality of evidence. Conclusion: There are substantial heterogeneity and several methodological concerns in the included studies. It was observed a positive association between diabetes mellitus and apical periodontitis with limited evidence, no association between HIV and apical periodontitis and a positive association between apical periodontitis and cardiovascular disease, blood disorders, chronic liver disease, osteoporosis and autoimmune diseases with moderate evidence.
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This study assessed the influence of pH variation on the volumetric change of EndoSequence BC Sealer compared to AH Plus Jet. Eighteen single-rooted teeth were uniformly prepared and filled with one of the sealers. After 24-h storing, samples were scanned in a micro-CT device. Then, roots were immersed in 20 ml phosphate-buffered saline (PBS) with pH of 5, 7 or 12 at 37°C for 7 and 30 days and rescanned. Statistical analysis was performed using Shapiro-Wilk's test, one-way ANOVA and Tukey's or Student's t-tests (p < 0.05). Differences between sealers were observed only at neutral pH and after 30 days of acidic pH exposure, with a higher loss of EndoSequence (p < 0.05). After 7 days, alkaline pH reduced and increased the volumetric loss of EndoSequence and AH Plus, respectively, compared to neutral pH (p < 0.05). It can be concluded that the pH directly influenced the volumetric change of both tested root canal sealers in different ways.
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Resinas Epoxi , Materiales de Obturación del Conducto Radicular , Humanos , Microtomografía por Rayos X , Compuestos de Calcio , Silicatos , Concentración de Iones de Hidrógeno , Ensayo de Materiales , Cavidad Pulpar/diagnóstico por imagenRESUMEN
This report describes the innovative application of high sensitivity Boron-doped nanocrystalline diamond microelectrodes for tracking small changes in Ca2+ concentration due to binding to Annexin-A5 inserted into the lipid bilayer of liposomes (proteoliposomes), which could not be assessed using common Ca2+ selective electrodes. Dispensing proteoliposomes to an electrolyte containing 1 mM Ca2+ resulted in a potential jump that decreased with time, reaching the baseline level after ~300 s, suggesting that Ca2+ ions were incorporated into the vesicle compartment and were no longer detected by the microelectrode. This behavior was not observed when liposomes (vesicles without AnxA5) were dispensed in the presence of Ca2+. The ion transport appears Ca2+-selective, since dispensing proteoliposomes in the presence of Mg2+ did not result in potential drop. The experimental conditions were adjusted to ensure an excess of Ca2+, thus confirming that the potential reduction was not only due to the binding of Ca2+ to AnxA5 but to the transfer of ions to the lumen of the proteoliposomes. Ca2+ uptake stopped immediately after the addition of EDTA. Therefore, our data provide evidence of selective Ca2+ transport into the proteoliposomes and support the possible function of AnxA5 as a hydrophilic pore once incorporated into lipid membrane, mediating the mineralization initiation process occurring in matrix vesicles.
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Diamante , Liposomas , Anexina A5/química , Anexina A5/metabolismo , Diamante/metabolismo , Membrana Dobles de Lípidos , Liposomas/química , MicroelectrodosRESUMEN
The surface of gutta-percha cones was evaluated after using five different cutting methods, including a new TipSnip device. The gutta-percha cones were cut off using: 1) TipSnip, 2) a single cut with a scalpel blade using a gauge, 3) two cuts with a scalpel blade using a gauge, 4) a razor blade against a glass slab or 5) scissors. Samples were examined under stereomicroscopy and observed by three highly qualified evaluators. The Kappa coefficient with a 95% confidence interval was used and all scores were tabulated and analyzed statistically using a nonparametric Kruskal-Wallis test with a 5% significance level. Cutting with scissors produced significant irregularities in the cone surface, providing the worst result. TipSnip, two cuts with scalpel blade, and cut with a razor against a glass slab provided the best results. A regular surface on the tips of gutta-percha cones improves apical fit, and may be achieved by means of different cutting methods.
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Gutapercha , Obturación del Conducto Radicular/métodos , Diseño de Equipo , Obturación del Conducto Radicular/instrumentaciónRESUMEN
This study aimed to evaluate the efficacy of supplementary methods to remove the remaining root filling material from root canals. Twenty mandibular single-rooted teeth were instrumented with Reciproc 25/0.08 and filled with gutta-percha and AH-Plus sealer, followed by a micro-CT scanning. The retreatment procedures were performed, the samples were rescanned and divided into two groups (n = 10) according to the supplementary method: XP-endo Finisher R and Clearsonic tip. The samples were rescanned and the volume of remaining root filling material was quantified. Data were analysed statistically (P < 0.05). The amount of filling material removed after supplementary methods was higher compared with retreatment procedure (P < 0.05). XP-endo Finisher R promoted a greater percentage of filling materials reduction in the entire root canal and apical third compared with Clearsonic tip (P < 0.05). Supplementary methods were effective in the reduction of root filling materials. XP-endo Finisher R removed more root filling material than Clearsonic tip.
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Materiales de Obturación del Conducto Radicular , UltrasonidoRESUMEN
This study evaluated the impact of COVID-19 on the endodontic treatment routine. It was a cross-sectional study using an online questionnaire applied to endodontists to collect information about practical modifications during endodontic treatment to protect professionals and patients against the COVID-19 outbreak. A total 1105 participants from Brazil participated in the survey. More than 90% of respondents identify the high risk of COVID-19 infection to dentists and the need to change some clinical practices. Most respondents (60.1%) are partially following social isolation. The need for a change in Personal Protective Equipment (PPE) during dental appointments was mentioned by 97.1% of respondents. The use of minimal adequate PPE during the pandemic period was associated with the area of residence and marital status of participants. Only 30% of respondents say they use the minimal adequate PPE. Most respondents will change cavity access preparation to reduce virus dissemination. Other changes in endodontic appointments were described in the survey: greater attention to biosafety measures, duration of dental appointments, and duration of intervals between appointments. Endodontists still need to identify the best arrangement for performing their procedures safely during the COVID-19 pandemic. Specific guidelines require detailed information for each specialty and its procedures.
Este estudo transversal foi realizado por meio de um questionário online. O questionário foi aplicado a endodontistas e coletou informações sobre modificações práticas durante o tratamento endodôntico para combater o surto de COVID-19 e proteger profissionais e pacientes. Um total de 1105 participantes do Brasil participaram da pesquisa. Mais de 90% dos entrevistados identificam o alto risco de infecção por COVID-19 para os dentistas e a necessidade de mudar algumas práticas clínicas. A maioria dos entrevistados (60,1%) segue parcialmente o isolamento social. A necessidade de mudanças dos Equipamentos de Proteção Individual (EPIs) durante as consultas odontológicas foi referida por 97,1% dos entrevistados. O uso de EPIs mínimos adequados durante o período pandêmico foi associado à área de residência e ao estado civil dos participantes. Apenas 30% dos participantes afirmou usar os EPIs mínimos durante a pandemia. A maioria dos entrevistados mudará a preparação do acesso à cavidade para reduzir a disseminação do vírus. Outras mudanças nas consultas endodônticas foram descritas na pesquisa: maior atenção às medidas de biossegurança, duração das consultas odontológicas e intervalos entre as consultas. Os endodontistas ainda precisam distinguir a melhor maneira para realizar seus procedimentos com segurança, durante a pandemia de COVID-19. Diretrizes específicas requerem informações detalhadas para cada especialidade e seus procedimentos.
Asunto(s)
COVID-19 , Endodoncistas , Brasil/epidemiología , Estudios Transversales , Humanos , Pandemias , Percepción , SARS-CoV-2 , Encuestas y CuestionariosRESUMEN
The genua Roquettea Mello-Leitão, hitherto monotypic and known from Brazilian state of Pará, is rediagnosed, the type species, Roquettea singularis is redescribed, including a report on two male morphs, being the second record of male polymorphism in Cosmetidae, the first in South America. Three new species are described from northern Brazil - Roquettea taurine n. sp. (which possesses a unique horned ocularium) and Roquettea jalapensis n. sp. (without notable scutal structures), both from the state of Tocantins, being the first record of the family Cosmetidae from Tocantins; and Roquettea scrotalis n. sp. (with a unique 2-balled dorsal tuberous complex) from Amapá state, being the first record of the subfamily Discosomaticinae from Amapá. Roquettea is compared to the closely related genus Gryne, both currently placed in Discosomaticinae, and also to Profus, the type genus of the subfamily. The unity of Discosomaticinae is discussed, and evidence for the monophyly of this subfamily is weak at best. Male genitalia are for the first time illustrated and described for genera Protus, Roquettea and Gryne, and SEM micrographs are used for the first time in descriptions of Cosmetidae.