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Background: Xylazine is an increasingly common adulterant in the North American unregulated drug supply that is associated with adverse health outcomes (e.g., skin infections, overdose). However, there are significant knowledge gaps regarding how xylazine was initially identified and how syringe services program (SSP) staff and clients (people who use drugs) responded to its emergence. Methods: From June-July 2023, we conducted qualitative interviews with medical (e.g., clinicians) and frontline SSP staff (e.g., outreach workers) and adult clients with a history of injection drug use at a Miami-based SSP. Inductive memos identified emergent codes; thematic analysis involving team consensus established final themes. Results: From interviews with SSP staff (n = 8) and clients (n = 17), xylazine emergence was identified at different times, in various ways. Initially, during summer 2022, clients identified a "tranquilizer-like substance" that worsened sedation and withdrawal and caused wounds. SSP medical staff later identified this adulterant as xylazine by treating new medical cases and through diverse information-sharing networks that included professional societies and news sources; however, frontline SSP staff and clients needed additional educational resources about xylazine and its side effects. With limited guidance on how to reduce harm from xylazine, SSP clients altered their drug consumption routes, reduced drug use, and relied on peers' experiences with the drug supply to protect themselves. Some individuals also reported preferring xylazine-adulterated opioids and increasing their drug use, including the use of stimulants to avoid over sedation. Conclusions: Xylazine's emergence characterizes the current era of unprecedented shifts in the unregulated drug supply. We found that xylazine spurred important behavioral changes among people who use drugs (e.g., transitioning from injecting to smoking). Incorporating these experiences into early drug warning surveillance systems and scaling up drug-checking services and safer smoking supply distribution could help mitigate significant health harms caused by xylazine and other emergent adulterants.
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BACKGROUND: Femoral fractures in children have the highest probability for abuse after skull fractures and humeral shaft fractures. However, the reported proportion of pediatric femur fractures that result from nonaccidental trauma (NAT) varies in the literature from 2% to 60%. The purpose of this study was to determine the patient characteristics associated with a physician's decision to conduct a NAT workup and challenge universal clinical practice guidelines stating that all children younger than 3 years with a diaphyseal femur fracture be evaluated for NAT. METHODS: A retrospective review was conducted on patients aged 0 to 36 months diagnosed with a femur fracture between January 1, 2004, and April 9, 2019, at our institution. NAT was defined as a diagnosis of trauma that was nonaccidental in the medical chart after a positive workup by skeletal survey, ophthalmological examination, or other appropriate referral made by the institution's child abuse and neglect team. Patients with incomplete medical records were excluded. RESULTS: A total of 299 patients were identified, and 22 were excluded. 71% (197/277) were screened for NAT. Patients younger than 1 year were significantly more likely to undergo a NAT workup (P = 0.009; Odds Ratio [OR], 2.3; 95% CI, 1.2 to 4.4) and receive a positive result from the NAT workup (P < 0.0005; OR, 11.3; 95% CI, 4.6 to 27.4). Additional injuries were also a significant predictor of a positive NAT workup (P < 0.001; OR, 5.3; 95% CI, 2.4 to 11.9). Patient race/ethnicity, sex, and fracture type were not markedly associated with the physician's decision to conduct a NAT workup. CONCLUSIONS: Infants younger than 1 year with a femur fracture and children younger than 3 years presenting with a femur fracture and another injury are at increased risk of possible NAT. While clinical practice guidelines may minimize racial bias in NAT evaluation, this study demonstrates that universal NAT workups for walking-age children in the absence of other evidence of abuse may be unnecessary. LEVEL OF EVIDENCE: This is a Level III retrospective cohort study.
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Glucagon is critical for the maintenance of blood glucose, however nutrient regulation of pancreatic α-cells remains poorly understood. Here, we identified a role of leucine, a well-known ß-cell fuel, in the α-cell-intrinsic regulation of glucagon release. In islet perifusion assays, physiologic concentrations of leucine strongly inhibited alanine- and arginine-stimulated glucagon secretion from human and mouse islets under hypoglycemic conditions. Mechanistically, leucine dose-dependently reduced α-cell cAMP, independently of Ca2+, ATP/ADP, or fatty acid oxidation. Leucine also reduced α-cell cAMP in islets treated with somatostatin receptor 2 antagonists or diazoxide, compounds that limit paracrine signaling from ß/δ-cells. Studies in dispersed mouse islets confirmed an α-cell-intrinsic effect. The inhibitory effect of leucine on cAMP was mimicked by glucose, α-ketoisocaproate, succinate, and the glutamate dehydrogenase activator BCH and blocked by cyanide, indicating a mechanism dependent on mitochondrial metabolism. Glucose dose-dependently reduced the impact of leucine on α-cell cAMP, indicating an overlap in function; however, leucine was still effective at suppressing glucagon secretion in the presence of elevated glucose, amino acids, and the incretin GIP. Taken together, these findings show that leucine plays an intrinsic role in limiting the α-cell secretory tone across the physiologic range of glucose levels, complementing the inhibitory paracrine actions of ß/δ-cells.
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AMP Cíclico , Células Secretoras de Glucagón , Glucagón , Leucina , Comunicación Paracrina , Animales , Glucagón/metabolismo , AMP Cíclico/metabolismo , Células Secretoras de Glucagón/metabolismo , Células Secretoras de Glucagón/efectos de los fármacos , Ratones , Humanos , Leucina/farmacología , Comunicación Paracrina/efectos de los fármacos , Glucosa/metabolismo , Cetoácidos/farmacología , Masculino , Islotes Pancreáticos/metabolismo , Islotes Pancreáticos/efectos de los fármacos , Ratones Endogámicos C57BL , Células Secretoras de Insulina/efectos de los fármacos , Células Secretoras de Insulina/metabolismoRESUMEN
INTRODUCTION: The COVID-19 pandemic changed the work routine of professionals at the family healthcare center (Núcleo de Atenção à Saúde da Família - NASF-AB), providing new conditions and work overload. OBJECTIVE: The purpose of this study was to explore factors associated with work overload in NASF-AB professionals during the COVID-19 pandemic. METHODS: A cross-sectional study was carried out with NASF-AB workers in the city of Salvador, Bahia, Brazil, from May to August 2021. Working conditions and overload were assessed using the National Program for Improving Access and the Quality of Primary Care questionnaire (Programa Nacional de Melhoria do Acesso e da Qualidade da Atenção Básica - PMAQ) and the scale measuring burden of professionals in mental health services (Escala de Avaliação da Sobrecarga de Profissionais em Serviços de Saúde Mental - IMPACTO-BR), respectively. A multivariate linear regression model was used. A total of 68 health professionals participated in the study, including 19 physiotherapists, 13 occupational therapists, 10 social workers, 10 nutritionists, 9 psychologists and 7 physical education professionals. RESULTS: There was a significant association between overall overload and being female (p=<0.005), having spaces for reflection on the work process (p=0.027), and having difficulty moving around to conduct activities in the territory (p=0.002) for increasing the chance of work overload. CONCLUSIONS: Our findings encourage workers' health policies and closer ties and negotiation with local management, as well as the return of the institutional support figure for the effectiveness and resolution of actions in primary healthcare units.
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BACKGROUND: DNA methylation plays an important role in studying the epigenetics of various biological processes including many diseases. Although differential methylation of individual cytosines can be informative, given that methylation of neighboring CpGs are typically correlated, analysis of differentially methylated regions is often of more interest. RESULTS: We have developed a probabilistic method and software, LuxHMM, that uses hidden Markov model (HMM) to segment the genome into regions and a Bayesian regression model, which allows handling of multiple covariates, to infer differential methylation of regions. Moreover, our model includes experimental parameters that describe the underlying biochemistry in bisulfite sequencing and model inference is done using either variational inference for efficient genome-scale analysis or Hamiltonian Monte Carlo (HMC). CONCLUSIONS: Analyses of real and simulated bisulfite sequencing data demonstrate the competitive performance of LuxHMM compared with other published differential methylation analysis methods.
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Algoritmos , Metilación de ADN , Teorema de Bayes , Epigénesis Genética , Sulfitos , Análisis de Secuencia de ADN/métodosRESUMEN
Background: We aimed to report the preliminary xylazine prevalence among people who inject drugs (PWID) treated at a student-run free clinic in Miami, FL, USA and to identify characteristics associated with screening positive for xylazine. Methods: A retrospective chart review of 59 patients presenting to a syringe services program (SSP) clinic in was conducted between April 27th and August 17th, 2023. We measured presence of xylazine with rapid visual immunoassay strips on patient urine samples. Results: Xylazine was present in 55.9 % (33/59) of urine samples including 2 without detected opioids. Xylazine presence was significantly associated with unsheltered homelessness (p = 0.018), presence of wound(s) (p = 0.008), and testing positive for hepatitis C antibody (p = 0.014), fentanyl (p = 0.005) and MDMA (p = 0.002). Conclusions: A high prevalence of xylazine in the Southeastern United States furthers evidence of the geographical spread of xylazine and rapidly evolving illicit drug supply. Widespread xylazine screening is urgently needed to inform people who inject drugs and to studyinterventions to minimize harms associated with xylazine.
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BACKGROUND: DNA methylation is commonly measured using bisulfite sequencing (BS-seq). The quality of a BS-seq library is measured by its bisulfite conversion efficiency. Libraries with low conversion rates are typically excluded from analysis resulting in reduced coverage and increased costs. RESULTS: We have developed a probabilistic method and software, LuxRep, that implements a general linear model and simultaneously accounts for technical replicates (libraries from the same biological sample) from different bisulfite-converted DNA libraries. Using simulations and actual DNA methylation data, we show that including technical replicates with low bisulfite conversion rates generates more accurate estimates of methylation levels and differentially methylated sites. Moreover, using variational inference speeds up computation time necessary for whole genome analysis. CONCLUSIONS: In this work we show that taking into account technical replicates (i.e. libraries) of BS-seq data of varying bisulfite conversion rates, with their corresponding experimental parameters, improves methylation level estimation and differential methylation detection.
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Análisis de Datos , Sulfitos , Metilación de ADN , Secuenciación de Nucleótidos de Alto Rendimiento , Análisis de Secuencia de ADNRESUMEN
CLINICAL RELEVANCE: Custom-made post-and-cores of polyetheretherketone (PEEK) and nano-ceramic composite showed good fracture resistance and failure mode. Clinicians should be aware that these materials might be an efficient alternative for post-and-cores, because they promote esthetics while reducing the risk of root fractures. SUMMARY: Purpose: The purpose of this study was to evaluate the fracture resistance and failure mode of custom-made post-and-cores manufactured with different esthetic materials.Methods and Materials: A total of 48 mandibular premolar extracted teeth were selected, endodontically treated, and prepared to receive the posts. Specimens were randomly divided into four groups (n=12/group): group 1, polyetheretherketone (PEEK, Degos; G1); group 2, nano-ceramic composite (Lava Ultimate, 3M ESPE; G2); group 3, cast metal post (NiCr alloy, control; G3); group 4, fiberglass post (Whitepost, FGM, control; G4) customized with a nano-hybrid resin composite (Z250, 3M ESPE). Experimental post-and-cores (G1 and G2) were manufactured with a computer-aided design/computer-aided manufacturing system. All posts were cemented with self-adhesive resin cement (Rely X U200, 3M ESPE), and specimens were stored in distilled water at 37°C for 60 days. A universal testing machine was used to measure the fracture resistance (0.5 mm/min at an angle of 45° to the long axis of the tooth). Fractures were classified as repairable or catastrophic. One-way analysis of variance with Tukey post hoc and χ2 tests for independence and Bonferroni adjustments were applied (α=0.05).Results: The fracture resistance values (mean ± SD, in newtons) were 379.4 ± 119.8 (G1), 506.4 ± 138 (G2), 939.6 ± 146.5 (G3), and 449.6 ± 66.5 (G4). Only G3 exhibited a significant difference (p<0.05). The χ2 test showed an association between failure mode and post-and-core material [χ2(3) = 23.65; p<0.001]. After Bonferroni adjustment, only G3 presented a higher than expected incidence of catastrophic failures (p<0.001). In the remaining groups, most failures were repairable and related to debonding.Conclusions: Customized post-and-cores of PEEK and nano-ceramic composites exhibited good mechanical performance. Their fracture resistance was comparable to that observed for fiberglass customized posts, yet lower than that for cast metal posts. For PEEK post-and-cores, in particular, additional studies are needed to improve adhesiveness and reduce the risk of debonding.
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Técnica de Perno Muñón , Fracturas de los Dientes , Diente no Vital , Benzofenonas , Resinas Compuestas , Fracaso de la Restauración Dental , Análisis del Estrés Dental , Vidrio , Humanos , Cetonas , Polietilenglicoles , PolímerosRESUMEN
Desde tempos remotos, a pelagem é valorizada no agronegócio equestre. Em animais Campolina, objetivou-se avaliar a ocorrência de pelagens e a distribuição entre sexos nos estados do Brasil, assim como verificar a frequência desse fenótipo nos acasalamentos e associá-lo com medidas lineares e qualidade da marcha. Foram selecionados 44.437 registros definitivos e utilizaram-se testes de qui-quadrado para avaliar a distribuição de pelagens entre sexos, estados e décadas. Por análise descritiva, foi obtida frequência de acasalamento dos fenótipos e proporções resultantes nos filhos. Foram contabilizados os indivíduos acasalados e os mais usados por décadas de nascimento e de registro. Pelagens baia, alazã e castanha predominaram, com 20.422; 11.941 e 5.256 animais, respectivamente. O fenótipo baio representou 45,21% em Minas Gerais; 46,98% no Rio de Janeiro e 48,98% em São Paulo. Para machos e fêmeas constatou-se maior frequência de pelagens baia, alazã e castanha. Os acasalamentos mais frequentes foram alazã x baia, baia x baia e baia x castanha. Este é o primeiro artigo a avaliar a ocorrência das pelagens em equinos da raça Campolina, sendo baia a mais prevalente em ambos os sexos. A qualidade da marcha ao registro não está associada à pelagem. Esse fenótipo deve ser usado com cautela na seleção.(AU)
Since ancient times, coat colors are valued in the equestrian business. The objective of this study was to evaluate the occurrence of coat colors and distribution among sexes in Brazil and also verify the frequency of this phenotype in reproduction to associate it with linear measurements and functionality. 44,437 definitive records were selected, and chi-square tests were used to evaluate coat colors and distribution between sexes, states and decades. By descriptive analysis the phenotypes breeding frequency and proportions in the offspring were obtained. Breeding and most used individuals were accounted by decade of birth and registration. Dun, chestnut and bay coat colors predominated, with 20,422; 11,941 and 5,256 animals, respectively. Dun represented 45.21% in Minas Gerais; 46.98% in Rio de Janeiro and 48.98% in São Paulo. For males and females there was a higher frequency of dun, chestnut and bay. The most frequent breeding colors were chestnut x dun, dun x dun and dun x bay. This is the first article to evaluate the coat colors in the Campolina population, dun being the most prevalent coat color in both sexes. The gait quality at the register is not associated with the coat color. This phenotype should be used with caution in selection.(AU)
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Animales , Fenotipo , Pelaje de Animal/anatomía & histología , Frecuencia de los Genes , CaballosRESUMEN
The objective of this study was to evaluate the effect of surface sealants and polishing delay time on a nanohybrid resin composite roughness and microhardness. Eighty disc specimens were made with a nanohybrid resin (Esthet-X HD, Dentsply). The specimens were divided into two groups (n=40) according to polishing time: immediate, after 10 minutes; delayed, after 48 hours. Each group was subdivided into four groups (n=10), according to the surface treatment: CG, control-rubber points (Jiffy Polishers, Ultradent); PP, rubber points + surface sealant (PermaSeal, Ultradent); PF, rubber points + surface sealant (Fortify, Bisco); PB, rubber points + surface sealant (BisCover, Bisco). Surface roughness (Ra) and microhardness (50 g/15 seconds) were measured. Surface morphology was analyzed by scanning electron microscopy and atomic force microscopy. The data were analyzed statistically using one-way analysis of variance and the Games-Howell post hoc test (α=0.05). PermaSeal roughness (G2) in the delayed polishing group was significantly higher ( p=0.00) than that of the other groups. No difference was observed among the groups between immediate and delayed polishing ( p=1.00), except for PermaSeal ( p=0.00). Moreover, PermaSeal showed the lowest microhardness values ( p=0.00) for immediate polishing. Microhardness was higher at delayed polishing for all the surface treatments ( p=0.00) except Fortify ( p=0.73). Surface smoothness similar to polishing with rubber points was achieved when surface sealants were used, except for PermaSeal surface sealant, which resulted in a less smooth resin composite surface. However, surface sealant application did not significantly improve composite resin microhardness.
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Resinas Compuestas/química , Materiales Dentales/química , Pulido Dental/métodos , Cementos de Resina/química , Acrilatos , Dureza , Curación por Luz de Adhesivos Dentales , Ensayo de Materiales , Propiedades de Superficie , Factores de TiempoRESUMEN
Rehydration of the tooth remnant and complete polymerization of the composite resin are aspects that should be considered in shade selection of composite resin. This article presents a case series of Class IV restorations performed to evaluate the color match between the composite resin and the tooth remnant. Thirteen Class IV restorations were performed in maxillary central incisors and evaluated according to the period following the restorative procedure: 10 minutes (baseline), 48 hours before and after finishing and polishing, and seven, 14, and 28 days. The color match of the restorations was evaluated by the ΔE values of the tooth remnant (TR) and the composite resin (CR) in each evaluation period using a spectrophotometer. The translucency, luminosity, and saturation were analyzed qualitatively in digital photographs of the restorations. The CR ΔE was statistically similar to the TR ΔE at 14 and 28 days ( p>0.05). The saturation and luminosity of most of the restorations remained unchanged, but there was a greater change in the translucency. The color match of the composite resin in Class IV restorations was observed after 14 days of clinical assessment in this case series.
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Resinas Compuestas/uso terapéutico , Restauración Dental Permanente/métodos , Incisivo/anatomía & histología , Coloración de Prótesis/métodos , Adulto , Color , Femenino , Humanos , Incisivo/cirugía , Masculino , Fotografía Dental , Espectrofotometría , Adulto JovenRESUMEN
OBJECTIVE: To describe the perceptions of patients, their caregivers, and their healthcare providers to the development of a new specific instrument for assessment of the quality of life (QoL) in patients with mucopolysaccharidoses (MPS) using a qualitative focus group (FG) design. FGs were held in two Brazilian states (Rio Grande do Sul and Rio de Janeiro). RESULTS: Three versions of the new instrument were developed, each for a different age group: children (age 8-12 years), adolescents (age 13-17), and adults (age ≥ 18). The FGs mostly confirmed the relevance of items. All FGs unanimously agreed on the facets: School, Happiness, Life Prospects, Religiosity, Pain, Continuity of Treatment, Trust in Treatment, Relationship with Family, Relationship with Healthcare Providers, Acceptance, and Meaning of Life. The overall concept of QoL (as proposed by the WHO-World Health Organization) and its facets apply to this patient population. However, other specific facets-particularly concerning clinical manifestations and the reality of the disease-were suggested, confirming the need for the development of a specific QoL instrument for MPS.
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Mucopolisacaridosis/psicología , Psicometría/métodos , Calidad de Vida/psicología , Adolescente , Adulto , Brasil , Cuidadores , Niño , Femenino , Grupos Focales , Personal de Salud , Humanos , Masculino , Persona de Mediana Edad , Psicometría/instrumentación , Adulto JovenRESUMEN
Early dietary treatment of phenylketonuria (PKU), an inborn error of phenylalanine (Phe) metabolism, results in normal cognitive development. Although health-related quality of life (HRQoL) of PKU patients has been reported as unaffected in high-income countries, there are scarce data concerning HRQoL and adherence to treatment of PKU children and adolescents from Brazil. The present study compared HRQoL scores in core dimensions of Brazilian early-treated PKU pediatric patients with those of a reference population, and explored possible relationships between adherence to treatment and HRQoL. Early-treated PKU pediatric patient HRQoL was evaluated by self- and parent-proxy reports of the Pediatric Quality of Life Inventory (PedsQL) core scales. Adherence to treatment was evaluated by median Phe levels and percentage of results within the therapeutic target range in two periods. Means for total and core scales scores of PedsQL self- and parent proxy-reports of PKU patients were significantly lower than their respective means for controls. Adequacy of median Phe concentrations and the mean percentage of values in the target range fell substantially from the first year of life to the last year of this study. There was no significant difference in mean total and core scale scores for self- and parent proxy-reports between patients with adequate and those with inadequate median Phe concentrations. The harmful consequences for intellectual capacity caused by poor adherence to dietary treatment could explain the observed decrease in all HRQoL scales, especially in school functioning. Healthcare system and financial difficulties may also have influenced negatively all HRQoL dimensions.
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Fenilcetonurias/dietoterapia , Calidad de Vida , Cumplimiento y Adherencia al Tratamiento/estadística & datos numéricos , Adolescente , Factores de Edad , Análisis de Varianza , Brasil , Niño , Femenino , Humanos , Pruebas de Inteligencia , Modelos Lineales , Masculino , Padres , Fenilalanina/sangre , Fenilcetonurias/psicología , Apoderado , Calidad de Vida/psicología , Prevención Secundaria , Autoinforme , Factores Socioeconómicos , Factores de Tiempo , Cumplimiento y Adherencia al Tratamiento/psicología , Resultado del TratamientoRESUMEN
OBJECTIVE: To assess the influence of adhesive core buildup designs (4-mm buildup, 2-mm buildup, and no buildup/endocrown) on the fatigue resistance and failure mode of endodontically treated molar teeth restored with lithium disilicate computer-aided design/computer-aided manufacturing (CAD/CAM) complete crowns placed with self-adhesive cement. METHODS AND MATERIALS: Forty-five extracted molars were decoronated at the level of the cementoenamel junction and endodontically treated. Specimens received different Filtek Z100 adhesive core buildups (4-mm buildup; 2-mm buildup; and no buildup endocrown preparation) and were restored with Cerec 3 CAD/CAM lithium disilicate crowns (IPS e.max CAD). The intaglio surfaces of restorations (n=15) were conditioned by hydrofluoric acid etching and silane, and prepared teeth were treated with airborne-particle abrasion, followed by cementation with RelyX Unicem 2 Automix. Specimens were then subjected to cyclic isometric loading at 10 Hz, beginning with a load of 200 N (×5000 cycles), followed by stages of 400, 600, 800, 1000, 1200, and 1400 N at a maximum of 30,000 cycles each. Specimens were loaded until failure or to a maximum of 185,000 cycles. The chewing cycle was simulated by an isometric contraction (load control) applied through a 10-mm in diameter composite resin sphere (Filtek Z100). Surviving specimens were axially loaded until failure or to a maximum load of 4500 N (crosshead speed 0.5 mm/min). The failure mode was assessed, and fractures were designated as catastrophic (tooth/root fracture that would require tooth extraction) or reparable (cohesive or cohesive/adhesive fracture of restoration only). Groups were compared using the life table survival analysis (log-rank test at p=0.05). Surviving specimens were loaded to failure and compared with one-way analysis of variance. RESULTS: The survival rates after the fatigue test were 100%, 93%, and 100% for 4-mm, 2-mm, and no buildup (endocrown), respectively and were not statistically different (only one specimen failed with a 2-mm buildup under a crown that cohesively fractured at 1,400 N). Postfatigue load to failure averaged 3181 N for 4-mm buildups (15 specimens), 3759 N for 2-mm buildups (12 specimens), and 3265 N for endocrowns (14 specimens). The 2-mm buildups were associated with higher loads to failure than endocrowns and 4-mm buildups, but no differences were found between 4-mm buildups and endocrowns (p<0.05.) One endocrown and 2 restorations with a 2-mm buildup survived the load-to-failure test (at 4500 N). Only catastrophic fractures occurred after the load-to-failure test. CONCLUSIONS: The buildup design influenced the performance of endodontically treated molars restored with lithium disilicate CAD/CAM complete crowns placed with self-adhesive resin cement. The 2-mm buildups were associated with higher loads to failure than the endocrown and the 4-mm buildup, but all restoration designs survived far beyond the normal range of masticatory forces.
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Diseño de Prótesis Dental , Fracaso de la Restauración Dental , Diseño Asistido por Computadora , Coronas , Cementos Dentales , Porcelana Dental , Análisis del Estrés Dental , Ensayo de Materiales , Diente Molar , Cementos de ResinaRESUMEN
OBJECTIVES: To evaluate the influence of adhesive core buildup designs-4-mm buildup, 2-mm buildup, and no buildup (endocrown)-on the fatigue resistance and failure mode of endodontically treated molar teeth restored with resin nanoceramic (RNC) CAD/CAM complete crowns placed with self-adhesive resin cement. METHODS AND MATERIALS: Forty-five extracted molars were decoronated at the level of the cementoenamel junction, and the roots were endodontically treated. Specimens received different Filtek Z100 adhesive core buildups (4-mm buildup, 2-mm buildup, and no buildup, endocrown preparation) and were restored with Cerec 3 CAD/CAM RNC crowns (Lava Ultimate). Restorations (n=15) and prepared teeth were treated with airborne-particle abrasion, followed by cementation with RelyX Unicem 2 Automix. Specimens were then subjected to cyclic isometric loading at 10 Hz, beginning with a load of 200 N (for 5000 cycles), followed by stages of 400, 600, 800, 1000, 1200, and 1400 N at a maximum of 30,000 cycles each. Specimens were loaded until failure or to a maximum of 185,000 cycles (10-mm-diameter composite resin sphere antagonist). The failure mode was assessed: "catastrophic" (tooth/root fracture that would require tooth extraction), "possibly reparable" (cohesive/adhesive failure with fragment and minor damage, chip or crack, of underlying tooth structure), or "reparable" fracture (cohesive or cohesive/adhesive fracture of restoration only). Groups were compared using the life table survival analysis. Intact specimens were loaded to failure and compared with one-way analysis of variance. RESULTS: All specimens survived the fatigue test until the 800 N-step. The survival rates for 4-mm, 2-mm, and no buildup (endocrown) were 53%, 87%, and 87%, respectively, and were not statistically different even though crowns with 2-mm buildups only started to fail at 1200 N. Minor cohesive chips were detected in many samples despite having survived all 185,000 cycles. Postfatigue load-to-failure ranged from 2969 N with 4-mm buildup (eight specimens), 2794 N for 2-mm buildup (13 specimens), and 2606 N for endocrowns (13 specimens) and were also not statistically different. There were only two catastrophic failures during the fatigue test and small subgingival delamination fractures and cracks (only with 4-mm buildup). All specimens in the load-to-failure test exhibited nonrestorable catastrophic fractures. CONCLUSIONS: There was no influence of the buildup design on the performance of endodontically treated molars restored with RNC CAD/CAM complete crowns placed with self-adhesive cement. All restoration designs survived the normal range of masticatory forces. Failure mode tended to be more favorable with the 2-mm buildup or no buildup (endocrown).
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Cerámica , Resinas Compuestas , Coronas , Diente Molar , Nanotecnología , Cementos de Resina , Tratamiento del Conducto Radicular , Humanos , Estrés MecánicoRESUMEN
BACKGROUND: Color assessment in aesthetic dentistry is one of the most challenging steps for direct restorative treatment. Shade selection tools should be able to mimic closely the materials and layering technique used in the final restoration, hence the development of prefabricated anatomic dual-laminate shade guides. OBJECTIVE: This study aims to compare different shade selection techniques and determine the suitability of a prefabricated anatomic dual-laminate shade guide and its best mode of use compared to a conventional guide and a layered custom guide. MATERIALS AND METHODS: CIELab coordinates of different shade guides were assessed: Vitapan Classical (tab A2; Vita); Miris2 prefabricated anatomic dual-laminate shade guide, enamel WR tab on top of dentine S3 tab and nothing in-between (M2air) or glycerin gel (M2gly) or water (M2w); custom shade guide using prefabricated silicon moulds, Miris2 enamel WR composite resin moulded directly on dentine S3 pre-polymerised base (M2cus). The average values were obtained to calculate DE and compare the different shade selection techniques. Additional samples and measurements were made to compare Vitapan Classical shade tabs A1, A2 and A3 and all possible combinations of Miris2 and establish the closest matching shade (DE 3.3). RESULTS: High DE values were found (6.519.11) when comparing M2air to Vita, M2gly M2w M2cus. Differences appeared acceptable (DE 2.092.99) between Vita, M2gly and M2w and M2cus. Seven combinations of M2 were found to match Vita tab A1 and A2 and three Miris2 combinations for Vita A3 (DE 3.3). CONCLUSIONS: The use of Miris2 prefabricated anatomic dual-laminate shade guide with interposition of water or glycerin between the enameldentine tabs demonstrated acceptable DE values when compared to Vitapan Classical and custom guides. A chart for matching Vita shades with various combinations of Miris2 enamel/dentine shades was produced to assist the clinician in obtaining acceptable restorations. CLINICAL SIGNIFICANCE: The prefabricated anatomic dual-laminate shade guide is as efficient as a custom shade guide, facilitating clinical steps and saving material when doing compositeresin restorations.
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Resinas Compuestas/química , Materiales Dentales/química , Coloración de Prótesis/instrumentación , Color , Esmalte Dental , Diseño de Prótesis Dental/instrumentación , Diseño de Prótesis Dental/normas , Dentina , Humanos , Coloración de Prótesis/métodos , Coloración de Prótesis/normas , Estándares de Referencia , Espectrofotometría/instrumentación , Propiedades de SuperficieRESUMEN
O presente artigo visa conhecer o contexto em que surge o curso de enfermagem no Hospital Geral de Santo António no Porto (Portugal) com vista a dotar o pessoal de enfermagem de competências técnicas, melhorando assim a assistência aos doentes deste estabelecimento de saúde. Num segundo momento, analisam-se os traços gerais da prática da enfermagem neste Hospital, incluindo o movimento associativista do pessoal de enfermagem. Pretende-se perceber qual a representação profissional da enfermagem neste contexto, bem como examinar a relevância da criação do curso de enfermagem neste Hospital portuense para a melhoria da prática de cuidados, aplicando uma metodologia qualitativa e quantitativa com base na análise histórica documental de fontes primárias, impressas e manuscritas
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Historia de la Enfermería , PortugalAsunto(s)
Enfermedades de la Coroides/epidemiología , Enfermedades Vasculares Periféricas/epidemiología , Anciano , Anciano de 80 o más Años , Brasil/epidemiología , Membrana Epirretinal/epidemiología , Femenino , Humanos , Degeneración Macular/complicaciones , Masculino , Persona de Mediana Edad , PrevalenciaRESUMEN
The aim of this study was to evaluate the effect of hormone replacement therapy (HRT) on the expression of Ki-67, bcl-2 and c-erb.B2 in endometrial polyps during menopause. Sixteen patients using HRT and 24 untreated controls with endometrial polyps were enrolled in this study. Polypectomy was carried out by hysteroscopy. The presence of c-erb.B2, bcl-2 and Ki-67 expression was determined by immunohistochemistry. HRT was found to decrease Ki-67 and bcl-2 expression in endometrial polyps without affecting the c-erb.B2 staining reaction. HRT may cause endometrial polyp involution by decreasing proliferation and stimulating apoptosis.
Asunto(s)
Neoplasias Endometriales/metabolismo , Terapia de Reemplazo de Estrógeno , Noretindrona/análogos & derivados , Pólipos/metabolismo , Administración Cutánea , Administración Oral , Anciano , Estudios de Casos y Controles , Estradiol/farmacología , Estrógenos Conjugados (USP)/farmacología , Femenino , Humanos , Inmunohistoquímica , Antígeno Ki-67/metabolismo , Acetato de Medroxiprogesterona/farmacología , Menopausia , Persona de Mediana Edad , Noretindrona/farmacología , Acetato de Noretindrona , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Receptor ErbB-2/metabolismo , Estudios RetrospectivosRESUMEN
Our objective was to investigate the presence of focal p53 expression in relation to proliferation rates in adenomyotic lesions during the menstrual cycle and in women on oral contraception. Fifty-nine perimenopausal patients with menorrhagia and adenomyosis were submitted to endometrial resection. The procedure was carried out during menstruation (n = 14), during the proliferative phase (n = 15), during the luteal phase (n = 20) or following the use of oral contraceptives (n = 10). The number of Ki-67-positive cells was low during menstruation, during the luteal phase and following the use of progestins. In the proliferative phase, on the other hand, there was a significant increase in the percentage of Ki-67-positive cells. Focal p53 expression was detected mainly during the proliferative phase of the menstrual cycle when proliferation rates were high. PTEN expression was detected in all cases irrespective of the phase of the menstrual cycle or use of oral contraception. We conclude that proliferation rates in adenomyotic lesions undergo marked cyclic variations and this affects the percentage of cases showing focal p53 expression in the glandular epithelium.