RESUMO
PURPOSE: This systematic review synthesized and analyzed the scientific evidence on the degree of conversion (DC) obtained by Fourier-transform infrared spectroscopy (FTIR) of light-cured and dual-cured resinous cements, photopolymerized under different thicknesses of vitreous ceramics. STUDY SELECTION: The study protocol of this systematic review was registered at the International Prospective Register of Systematic Reviews (PROSPERO) (CRD42017069319). A comprehensive search (PubMed/MEDLINE, Scopus, EMBASE, and LILACS) was performed for papers including an in vitro design and indexed from January 2007 to December 2020 according to the study purposes. A quality appraisal (specific instrument) and descriptive analysis of the articles that met the inclusion criteria were conducted. RESULTS: Nine included studies were analyzed. Two of them used feldspathic ceramics, six used lithium disilicate, and one used both (comparing different types and opacities of ceramics). Three studies found a higher DC in dual cements, while one did not find any significant differences, and five studies found a higher DC in light-cured resin cements. Light-cured cements showed a better DC in relation to dual-cured cements in vitreous ceramic restorations with thicknesses up to 2 mm. CONCLUSION: According to the findings, the use of good photoactivation is the most relevant variable to achieve an adequate DC in light-cured and dual-cured resin cements. The use of vitreous ceramic restorations with a thickness of less than 2 mm (light-curing cements) shows a better DC. Standardized in vitro studies are required to generate accurate scientific evidence.
Assuntos
Cerâmica , Cimentos de Resina , Cerâmica/química , Teste de Materiais , Cimentos de Resina/químicaRESUMO
Tropical mountain ecosystems are threatened by climate and land-use changes. Their diversity and complexity make projections how they respond to environmental changes challenging. A suitable way are trait-based approaches, by distinguishing between response traits that determine the resistance of species to environmental changes and effect traits that are relevant for species' interactions, biotic processes, and ecosystem functions. The combination of those approaches with land surface models (LSM) linking the functional community composition to ecosystem functions provides new ways to project the response of ecosystems to environmental changes. With the interdisciplinary project RESPECT, we propose a research framework that uses a trait-based response-effect-framework (REF) to quantify relationships between abiotic conditions, the diversity of functional traits in communities, and associated biotic processes, informing a biodiversity-LSM. We apply the framework to a megadiverse tropical mountain forest. We use a plot design along an elevation and a land-use gradient to collect data on abiotic drivers, functional traits, and biotic processes. We integrate these data to build the biodiversity-LSM and illustrate how to test the model. REF results show that aboveground biomass production is not directly related to changing climatic conditions, but indirectly through associated changes in functional traits. Herbivory is directly related to changing abiotic conditions. The biodiversity-LSM informed by local functional trait and soil data improved the simulation of biomass production substantially. We conclude that local data, also derived from previous projects (platform Ecuador), are key elements of the research framework. We specify essential datasets to apply this framework to other mountain ecosystems.
Assuntos
Biodiversidade , Ecossistema , Biomassa , Equador , FlorestasRESUMO
Biodiversity and ecosystem functions are highly threatened by global change. It has been proposed that geodiversity can be used as an easy-to-measure surrogate of biodiversity to guide conservation management. However, so far, there is mixed evidence to what extent geodiversity can predict biodiversity and ecosystem functions at the regional scale relevant for conservation planning. Here, we analyse how geodiversity computed as a compound index is suited to predict the diversity of four taxa and associated ecosystem functions in a tropical mountain hotspot of biodiversity and compare the results with the predictive power of environmental conditions and resources (climate, habitat, soil). We show that combinations of these environmental variables better explain species diversity and ecosystem functions than a geodiversity index and identified climate variables as more important predictors than habitat and soil variables, although the best predictors differ between taxa and functions. We conclude that a compound geodiversity index cannot be used as a single surrogate predictor for species diversity and ecosystem functions in tropical mountain rain forest ecosystems and is thus little suited to facilitate conservation management at the regional scale. Instead, both the selection and the combination of environmental variables are essential to guide conservation efforts to safeguard biodiversity and ecosystem functions.
Assuntos
Biodiversidade , Ecossistema , Meio Ambiente , Clima Tropical , Clima , Florestas , Modelos Teóricos , SoloRESUMO
Introducción y objetivos: La cirugía radioguiada es una técnica de tratamiento quirúrgico mínimamente invasivo del hiperparatiroidismo primario. Los objetivos de este estudio fueron estudiar el porcentaje de éxito de esta técnica y realizar una comparación de la misma con el estudio histológico intraoperatorio. Métodos: Estudiamos retrospectivamente a 84 pacientes con hiperparatirodismo primario con gammagrafía paratiroidea positiva. Se administró una dosis de Tc-99 m sestamibi previa a la cirugía y se utilizó una sonda gammadetectora intraoperatoria para detectar el tejido paratiroideo anómalo, siguiendo la «regla del 20%». En todos los casos se realizó estudio anatomopatológico intraoperatorio y seguimiento clínico y analítico durante al menos 6 meses. Asimismo, se comparó el valor predictivo positivo de la ecografía cervical respecto a la gammagrafía paratiroidea. Resultados: El porcentaje de éxito de la cirugía radioguiada fue 99%. La sonda gammadetectora intraoperatoria tuvo una sensibilidad, especificidad, valores predictivos positivo y negativo respecto al estudio histológico intraoperatorio de 99, 73, 97 y 89%, respectivamente. La calcemia se normalizó en 83 de 84 pacientes (99%) y la paratohormona se normalizó en 77 de los 84 pacientes (92%). La ecografía mostró un bajo valor predictivo positivo (41%) comparada con la gammagrafía. Conclusiones: La cirugía radioguiada es una técnica con excelentes resultados en el tratamiento quirúrgico mínimamente invasivo del hiperparatiroidismo primario y podría sustituir tanto al estudio anatomopatológico intraoperatorio como a la determinación intraoperatoria de paratohormona. Esta última posibilidad debe ser demostrada en futuros estudios (AU)
Introduction and objectives: Radioguided surgery is a minimally invasive surgical technique for the treatment of primary hyperparathyroidism. The goals of our study were to evaluate the rate of success and compare the results with intraoperative histological analysis. Methods: We retrospectively studied 84 patients with primary parathyroidism who had undergone radioguided surgery. All the patients had a positive parathyroid scintigraphy prior to surgery. An intravenous injection of Tc-99 m sestamibi was administered before surgery, and radioguided location of the pathologic parathyroid tissue was performed using an intraoperative gamma probe, applying the "20% rule". All resected specimens underwent intraoperative histologic analysis. All patients were followed up for at least 6 months. Positive predictive values of both parathyroid scintigraphy and cervical ultrasonography were also compared. Results: Radioguided surgery success rate was 99%. Sensitivity, specificity, positive and negative predictive values for gamma probe were 99, 73, 97 and 89%, respectively. After surgery, 83 of 84 patients were eucalcaemic (99%) and parathyroid hormone normalised in 77 of 84 patients (92%). Ultrasonography showed low positive predictive value (41%) when compared with scintigraphy. Conclusions: Radioguided surgery is a minimally invasive surgical technique with excellent results for the treatment of primary hyperparathyroidism and could replace both intraoperative histological analysis and intraoperative parathyroid hormone assay. Further studies are needed to confirm these findings (AU)
Assuntos
Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Hiperparatireoidismo Primário/diagnóstico , Hiperparatireoidismo Primário/patologia , Hiperparatireoidismo Primário/cirurgia , Cintilografia/tendências , Ultrassonografia/tendências , Hiperparatireoidismo Primário/complicações , Hiperparatireoidismo Primário/diagnóstico por imagem , Hiperparatireoidismo Primário/etiologia , Cirurgia Assistida por Computador/métodosRESUMO
INTRODUCTION AND OBJECTIVES: Radioguided surgery is a minimally invasive surgical technique for the treatment of primary hyperparathyroidism. The goals of our study were to evaluate the rate of success and compare the results with intraoperative histological analysis. METHODS: We retrospectively studied 84 patients with primary parathyroidism who had undergone radioguided surgery. All the patients had a positive parathyroid scintigraphy prior to surgery. An intravenous injection of Tc-99m sestamibi was administered before surgery, and radioguided location of the pathologic parathyroid tissue was performed using an intraoperative gamma probe, applying the "20% rule". All resected specimens underwent intraoperative histologic analysis. All patients were followed up for at least 6 months. Positive predictive values of both parathyroid scintigraphy and cervical ultrasonography were also compared. RESULTS: Radioguided surgery success rate was 99%. Sensitivity, specificity, positive and negative predictive values for gamma probe were 99, 73, 97 and 89%, respectively. After surgery, 83 of 84 patients were eucalcaemic (99%) and parathyroid hormone normalised in 77 of 84 patients (92%). Ultrasonography showed low positive predictive value (41%) when compared with scintigraphy. CONCLUSIONS: Radioguided surgery is a minimally invasive surgical technique with excellent results for the treatment of primary hyperparathyroidism and could replace both intraoperative histological analysis and intraoperative parathyroid hormone assay. Further studies are needed to confirm these findings.
Assuntos
Hiperparatireoidismo Primário/patologia , Hiperparatireoidismo Primário/cirurgia , Compostos Radiofarmacêuticos , Cirurgia Assistida por Computador , Tecnécio Tc 99m Sestamibi , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Hiperparatireoidismo Primário/diagnóstico por imagem , Período Intraoperatório , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Adulto JovemRESUMO
La especie Bifidobacterium scardovii está constituida por bacilos gram positivos anaerobios facultativos, cuyo desarrollo es estimulado por el CO2 y la anaerobiosis. Excepcionalmente se la ha asociado a infecciones humanas. Se presenta el caso de un paciente anoso con infección urinaria por B. scardovii y Enterococcus faecalis, ambos microorganismos aislados en 2 urocultivos consecutivos. El bacilo no desarrolló en los medios de cultivo habituales, pero sí en agar chocolate en CO2 y en agar Brucella suplementado, incubados durante 72 h a 35°C. La coloración de Gram alertó acerca de su presencia al observarse abundantes bacilos gram positivos irregulares con extremos bifurcados en forma de Y, y escasos cocos gram positivos. Es importante la coloración de Gram en orinas con piuria y la siembra en medios enriquecidos por tiempos prolongados. En este caso, sin el resultado del Gram y con el desarrollo de E. faecalis, no hubiésemos advertido la presencia del agente mayoritario.
Bifidobacterium scardovii species consists of facultative anaerobic gram-positive rods whose growth is stimulated by CO2 and anaerobiosis. Exceptionally it has been associated with infections in humans. An elderly male patient with a urinary tract infection due to B. scardovii and Enterococcus faecalis is presented here; both microorganisms were isolated from two consecutive urine samples. The bacillus did not grow on standard media, but on chocolate agar incubated in CO2 and on supplemented Brucella agar in an anaerobic atmosphere, incubated for 72 h at 35°C. Gram staining with abundant irregular gram-positive rods with Y-shaped ends and some gram-positive cocci alerted to its presence. The importance of the Gram stain test in urine samples with pyuria and the growth on enriched media for long periods is highlighted here. In this case, if we had not had the Gram stain test results, and had considered only the E. faecalis growth, we would have lost the major etiologic agent.
Assuntos
Idoso , Humanos , Masculino , Infecções Urinárias , Bifidobacterium , Infecções por Bifidobacteriales , Infecções Urinárias/microbiologia , Urina , Bifidobacterium/isolamento & purificação , Infecções por Bifidobacteriales/microbiologia , AnaerobioseRESUMO
Bifidobacterium scardovii species consists of facultative anaerobic gram-positive rods whose growth is stimulated by CO2 and anaerobiosis. Exceptionally it has been associated with infections in humans. An elderly male patient with a urinary tract infection due to B. scardovii and Enterococcus faecalis is presented here; both microorganisms were isolated from two consecutive urine samples. The bacillus did not grow on standard media, but on chocolate agar incubated in CO2 and on supplemented Brucella agar in an anaerobic atmosphere, incubated for 72h at 35°C. Gram staining with abundant irregular gram-positive rods with Y-shaped ends and some gram-positive cocci alerted to its presence. The importance of the Gram stain test in urine samples with pyuria and the growth on enriched media for long periods is highlighted here. In this case, if we had not had the Gram stain test results, and had considered only the E. faecalis growth, we would have lost the major etiologic agent.
Assuntos
Infecções por Bifidobacteriales , Bifidobacterium , Infecções Urinárias , Idoso , Anaerobiose , Infecções por Bifidobacteriales/microbiologia , Bifidobacterium/isolamento & purificação , Humanos , Masculino , Infecções Urinárias/microbiologia , UrinaRESUMO
Se presentan 2 casos de bacteriemias insidiosas por bacilos gram negativos anaerobios curvos, espiralados, móviles e infrecuentes en pacientes atendidos en un hospital de la ciudad de Buenos Aires. Estas bacteriemias, asociadas al aislamiento de Anaerobiospirillum y Desulfovibrio, fueron de origen poco claro y afectaron a pacientes inmunocomprometidos, con patologías simultáneas. Pruebas claves en la identificación del género Anaerobiospirillum fueron el estudio de la micromorfología, su carácter de anaerobio estricto, el resultado negativo en la prueba de catalasa, el patrón de discos de interés taxonómico, la fermentación de glucosa y la producción de β-N-acetilglucosaminidasa. El género Desulfovibrio se diferenció por el perfil presentado en las pruebas con discos, por ser asacarolítico, sin actividad de enzimas glucosídicas, y por producir desulfoviridina y H2S. Se alerta sobre la resistencia o sensibilidad intermedia de Anaerobiospirillum succiniciproducens (especie a la que correspondió el aislado de Anaerobiospirillum) a algunos de los antimicrobianos de primera línea frente a bacilos gram negativos anaerobios, como el metronidazol; fueron activas las combinaciones de aminopenicilinas con inhibidores de β-lactamasas y el imipenem. Desulfovibrio desulfuricans (especie a la que correspondió el aislado de Desulfovibrio) fue productora de β-lactamasas y resistente a las cefalosporinas; en cambio, fueron activos el metronidazol, el imipenem y la levofloxacina. La identificación confiable de estos microorganismos orienta hacia el mejor esquema terapéutico.
Two cases of insidious bacteremia by uncommon curve and spiral-shaped, motile anaerobic gram-negative rods are presented. Both of them were of an unclear origin and occurred in immunosuppressed patients with simultaneous diseases. The key tests for the identification of Anaerobiospirillum were its micromorphology, a strictly anaerobic condition, negative catalase activity, the special-potency disk profile, glucose fermentation, and β-NAG production. Desulfovibrio species was identified by all the above preliminary tests but with a different disk profile, as well as for being asaccharolytic and desulfoviridin and H2S producer. We here alert about the resistance or intermediate susceptibility of Anaerobiospirillum succiniciproducens against antimicrobial agents, such as metronidazole, one of the first-line drugs used for the treatment of anaerobic gram-negative infections. Aminopenicillins with β-lactamase-inhibitor combinations and imipenem were active for this agent. Desulfovibrio desulfuricans was β-lactamase producer and resistant to cephalosporins, while metronidazole, imipenem and levofloxacin were active. A reliable identification of these microorganisms is important for establishing the best therapeutic scheme.
Assuntos
Humanos , Infecções por Bactérias Gram-Negativas , Bacteriemia/microbiologia , Anaerobiospirillum , Desulfovibrio desulfuricans , Hospedeiro Imunocomprometido , Infecções por Bactérias Gram-Negativas/diagnóstico , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Anaerobiospirillum/isolamento & purificação , Desulfovibrio desulfuricans/isolamento & purificação , AntibacterianosRESUMO
Two cases of insidious bacteremia by uncommon curve and spiral-shaped, motile anaerobic gram-negative rods are presented. Both of them were of an unclear origin and occurred in immunosuppressed patients with simultaneous diseases. The key tests for the identification of Anaerobiospirillum were its micromorphology, a strictly anaerobic condition, negative catalase activity, the special-potency disk profile, glucose fermentation, and ß-NAG production. Desulfovibrio species was identified by all the above preliminary tests but with a different disk profile, as well as for being asaccharolytic and desulfoviridin and H2S producer. We here alert about the resistance or intermediate susceptibility of Anaerobiospirillum succiniciproducens against antimicrobial agents, such as metronidazole, one of the first-line drugs used for the treatment of anaerobic gram-negative infections. Aminopenicillins with ß-lactamase-inhibitor combinations and imipenem were active for this agent. Desulfovibrio desulfuricans was ß-lactamase producer and resistant to cephalosporins, while metronidazole, imipenem and levofloxacin were active. A reliable identification of these microorganisms is important for establishing the best therapeutic scheme.
Assuntos
Anaerobiospirillum , Bacteriemia/microbiologia , Desulfovibrio desulfuricans , Infecções por Bactérias Gram-Negativas , Anaerobiospirillum/isolamento & purificação , Antibacterianos , Desulfovibrio desulfuricans/isolamento & purificação , Infecções por Bactérias Gram-Negativas/diagnóstico , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Humanos , Hospedeiro ImunocomprometidoRESUMO
BACKGROUND: CD44s (standard isoform) is a cell adhesion molecule belonging to the family of the hyaluronan-binding proteins. The CD44 family has been found to be overexpressed in epithelial tumors, where they are generally in relationship with tumor growth and metastasic properties. The aim of this work was to evaluate the membranous CD44s content in colorectal cancer and in healthy surrounding mucosa, its possible relationship with clinicopathological parameters, and its potential prognostic significance. MATERIALS AND METHODS: Membranous CD44s levels were measured by an immunoenzymatic assay in tumors and surrounding mucosa samples from 72 patients with resectable colorectal carcinomas. The patients were followed for a mean time period of 30 months. RESULTS: There was a wide variability of CD44s levels in tumor-surrounding mucosal samples (26.6-727 ng/mg protein) as well as in tumors (28.5-381 ng/mg protein). Tumor samples showed significantly higher CD44s levels (median: 99.1 ng/mg protein) than surrounding mucosal samples (81 ng/mg protein) (p=0.03). In the same way, CD44s levels in tumors as well as in surrounding mucosal samples were significantly higher in high S-phase tumors than in low S-phase tumors (p=0.001 for both). There was no significant relationship between tumor CD44s levels and patient's outcome. However, high levels of the glycoprotein in nonneoplastic surrounding mucosa were significantly (p=0.018) associated with a poor overall patient survival. CONCLUSION: CD44s may play a role in the tumorogenesis of colorectal carcinomas. In addition, CD44s levels in tumor-surrounding mucosa may provide, in concert with some clinicopathological parameters, important information about prognostic evaluation of patients with resectable colorectal carcinomas.