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1.
Biophys J ; 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38902924

RESUMEN

Plant development relies on the precise coordination of cell growth, which is influenced by the mechanical constraints imposed by rigid cell walls. The hormone auxin plays a crucial role in regulating this growth by altering the mechanical properties of cell walls. During the postembryonic formation of lateral roots, pericycle cells deep within the main root are triggered by auxin to resume growth and divide to form a new root. This growth involves a complex interplay between auxin, growth, and the resolution of mechanical conflicts with the overlying endodermis. However, the exact mechanisms by which this coordination is achieved are still unknown. Here, we propose a model that integrates tissue mechanics and auxin transport, revealing a connection between the auxin-induced relaxation of mechanical stress in the pericycle and auxin signaling in the endodermis. We show that the endodermis initially limits the growth of pericycle cells, resulting in a modest initial expansion. However, the associated stress relaxation is sufficient to redirect auxin to the overlying endodermis, which then actively accommodates the growth, allowing for the subsequent development of the lateral root. Our model uncovers that increased pericycle turgor and decreased endodermal resistance license expansion of the pericycle and how the topology of the endodermis influences the formation of the new root. These findings highlight the interconnected relationship between mechanics and auxin flow during lateral root initiation, emphasizing the vital role of the endodermis in shaping root development through mechanotransduction and auxin signaling.

2.
Stroke ; 55(7): 1767-1775, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38748598

RESUMEN

BACKGROUND: Studies comparing bridging intravenous thrombolysis (IVT) with direct endovascular therapy (EVT) in patients with acute ischemic stroke who present late are limited. We aimed to compare the clinical outcomes and safety of bridging IVT in patients with acute ischemic stroke due to anterior circulation large vessel occlusion who underwent EVT 6 to 24 hours after time last known well. METHODS: We enrolled patients with anterior circulation large vessel occlusion stroke and a National Institutes of Health Stroke Scale score of ≥6 from 20 centers across 10 countries in the multicenter retrospective CLEAR study (CT for Late Endovascular Reperfusion) between January 2014 and May 2022. We used inverse probability of treatment weighting modeling adjusted for clinical and imaging confounders to compare functional outcomes, reperfusion success, symptomatic intracranial hemorrhage, and mortality between EVT patients with and without prior IVT. RESULTS: Of 5098 patients screened for eligibility, we included 2749 patients, of whom 549 received bridging IVT before EVT. The timing of IVT was not recorded. Witnessed stroke onset and transfer rates were higher in the bridging IVT group (25% versus 12% and 77% versus 55%, respectively, P value for both <0.0001), and time intervals between stroke onset and treatment were shorter (time last known well-start of EVT median 560 minutes [interquartile range, 432-791] versus 724 minutes [interquartile range, 544-912]; P<0.0001). After adjustment for confounders, there was no difference in functional outcome at 3 months (adjusted common odds ratio for modified Rankin Scale shift, 1.03 [95% CI, 0.89-1.19]; P=0.72) or successful reperfusion (adjusted odds ratio, 1.19 [95% CI, 0.81-1.75]; P=0.39). There were no safety concerns associated with bridging IVT versus direct EVT (symptomatic intracranial hemorrhage: adjusted odds ratio, 0.75 [95% CI, 0.38-1.48]; P=0.40; mortality: adjusted odds ratio, 1.14 [95% CI, 0.89-1.46]; P=0.31). Results were unchanged when the analysis was limited to patients who received IVT >6 hours after last known well. CONCLUSIONS: In patients with an anterior circulation large vessel occlusion stroke who underwent EVT 6 to 24 hours from last known well, bridging IVT was not associated with a difference in outcomes compared with direct EVT. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04096248.


Asunto(s)
Procedimientos Endovasculares , Accidente Cerebrovascular Isquémico , Terapia Trombolítica , Humanos , Masculino , Femenino , Anciano , Accidente Cerebrovascular Isquémico/terapia , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Accidente Cerebrovascular Isquémico/cirugía , Procedimientos Endovasculares/métodos , Persona de Mediana Edad , Terapia Trombolítica/métodos , Resultado del Tratamiento , Estudios Retrospectivos , Anciano de 80 o más Años , Fibrinolíticos/uso terapéutico , Fibrinolíticos/administración & dosificación , Tiempo de Tratamiento , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/terapia
3.
Stroke ; 55(2): 278-287, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38252759

RESUMEN

BACKGROUND: The association between sex and outcome after endovascular thrombectomy of acute ischemic stroke is unclear. The aim of this study was to compare the clinical and safety outcomes between men and women treated with endovascular thrombectomy in the late 6-to-24-hour window period. METHODS: This multicenter, retrospective observational cohort study included consecutive patients who underwent endovascular thrombectomy of anterior circulation stroke in the late window from 66 clinical sites in 10 countries from January 2014 to May 2022. The primary outcome was the 90-day ordinal modified Rankin Scale score. Secondary outcomes included 90-day functional independence (FI), return of Rankin (RoR) to prestroke baseline, FI or RoR, symptomatic intracranial hemorrhage, and mortality. Multivariable and inverse probability of treatment weighting methods were used. We explored the interaction of sex with baseline characteristics on the outcomes ordinal modified Rankin Scale and FI or RoR. RESULTS: Of 1932 patients, 1055 were women and 877 were men. Women were older (77 versus 69 years), had higher rates of atrial fibrillation, hypertension, and greater prestroke disability, but there was no difference in baseline National Institutes of Health Stroke Scale score. Inverse probability of treatment weighting analysis showed no difference between women and men in ordinal modified Rankin Scale (odds ratio, 0.98 [95% CI, 0.79-1.21]), FI or RoR (odds ratio, 0.98 [95% CI, 0.78-1.22]), severe disability or mortality (odds ratio, 0.99 [95% CI, 0.80-1.23]). The multivariable analysis of the above end points was concordant. There were no interactions between baseline characteristics and sex on the outcomes of ordinal modified Rankin Scale and FI or RoR. CONCLUSIONS: In late presenting patients with anterior circulation stroke treated with endovascular thrombectomy in the 6 to 24-hour window, there was no difference in clinical or safety outcomes between men and women.


Asunto(s)
Fibrilación Atrial , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Estados Unidos , Humanos , Femenino , Masculino , Caracteres Sexuales , Estudios Retrospectivos , Accidente Cerebrovascular/cirugía
4.
Bioinformatics ; 39(1)2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36661327

RESUMEN

SUMMARY: Here, we present sbml2hyb, an easy-to-use standalone Python tool that facilitates the conversion of existing mechanistic models of biological systems in Systems Biology Markup Language (SBML) into hybrid semiparametric models that combine mechanistic functions with machine learning (ML). The so-formed hybrid models can be trained and stored back in databases in SBML format. The tool supports a user-friendly export interface with an internal format validator. Two case studies illustrate the use of the sbml2hyb tool. Additionally, we describe HMOD, a new model format designed to support and facilitate hybrid models building. It aggregates the mechanistic model information with the ML information and follows as close as possible the SBML rules. We expect the sbml2hyb tool and HMOD to greatly facilitate the widespread usage of hybrid modeling techniques for biological systems analysis. AVAILABILITY AND IMPLEMENTATION: The Python interface, source code and the example models used for the case studies are accessible at: https://github.com/r-costa/sbml2hyb. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Asunto(s)
Lenguajes de Programación , Biología de Sistemas , Biología de Sistemas/métodos , Modelos Biológicos , Programas Informáticos , Lenguaje
5.
Biotechnol Bioeng ; 121(5): 1554-1568, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38343176

RESUMEN

The combination of physical equations with deep learning is becoming a promising methodology for bioprocess digitalization. In this paper, we investigate for the first time the combination of long short-term memory (LSTM) networks with first principles equations in a hybrid workflow to describe human embryonic kidney 293 (HEK293) culture dynamics. Experimental data of 27 extracellular state variables in 20 fed-batch HEK293 cultures were collected in a parallel high throughput 250 mL cultivation system in an industrial process development setting. The adaptive moment estimation method with stochastic regularization and cross-validation were employed for deep learning. A total of 784 hybrid models with varying deep neural network architectures, depths, layers sizes and node activation functions were compared. In most scenarios, hybrid LSTM models outperformed classical hybrid Feedforward Neural Network (FFNN) models in terms of training and testing error. Hybrid LSTM models revealed to be less sensitive to data resampling than FFNN hybrid models. As disadvantages, Hybrid LSTM models are in general more complex (higher number of parameters) and have a higher computation cost than FFNN hybrid models. The hybrid model with the highest prediction accuracy consisted in a LSTM network with seven internal states connected in series with dynamic material balance equations. This hybrid model correctly predicted the dynamics of the 27 state variables (R2 = 0.93 in the test data set), including biomass, key substrates, amino acids and metabolic by-products for around 10 cultivation days.


Asunto(s)
Memoria a Corto Plazo , Redes Neurales de la Computación , Humanos , Células HEK293 , Riñón
6.
J Esthet Restor Dent ; 36(5): 746-760, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38130045

RESUMEN

OBJECTIVE: This scoping review aims to assess the influence of air abrasion with aluminum oxide and bioactive glass on dentin bond strength. MATERIALS AND METHODS: An electronic search was conducted in three databases (PubMed, Cochrane Library, and Embase), on March 3rd, 2023, with previously identified MeSH Terms. A total of 1023 records were screened. Exclusion criteria include primary teeth, air abrasion of a substrate other than sound dentin, use of particles apart from aluminum oxide or bioactive glass, and studies in which bond strength was not assessed. RESULTS: Out of the 1023 records, title and abstract screening resulted in the exclusion of 895 and 67 studies, respectively, while full-text analysis excluded another 25 articles. In addition, 5 records were not included, as full texts could not be obtained after requesting the authors. Two cross-references were added. Thus, 33 studies were included in this review. It is important to emphasize the absence of standardization of air abrasion parameters. According to 63.6% of the studies, air abrasion does not influence dentin bond strength. Moreover, 30.3% suggest improving bonding performance, and 6.1% advocate a decrease. CONCLUSIONS: Air abrasion with aluminum oxide does not enhance or impair dentin bond strength. The available data on bioactive glass are limited, which hinders conclusive insights. CLINICAL SIGNIFICANCE: Dentin air abrasion is a widely applied technique nowadays, with numerous clinical applications. Despite the widespread adoption of this procedure, its potential impact on bonding performance requires a thorough analysis of the existing literature.


Asunto(s)
Resinas Compuestas , Recubrimiento Dental Adhesivo , Resinas Compuestas/química , Recubrimiento Dental Adhesivo/métodos , Abrasión Dental por Aire/métodos , Ensayo de Materiales , Propiedades de Superficie , Óxido de Aluminio/química , Dentina , Cementos de Resina/química
7.
J Esthet Restor Dent ; 36(4): 606-619, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37698359

RESUMEN

OBJECTIVE: This review aims to assess structural, chemical, and mechanical properties of coronal dentin after endodontic irrigation. MATERIALS AND METHODS: Reporting followed the PRISMA extension for scoping reviews. An electronic search was carried out in PubMed, Embase, and Cochrane Library. Records filtered by language and published up to November 4, 2022 were independently screened by two researchers. Studies evaluating structural, chemical, or mechanical properties of human permanent coronal dentin after irrigation within the scope of nonsurgical root canal treatment were included. Data were extracted regarding study type, sample description and size, experimental groups, outcome, evaluation method, and main findings. RESULTS: From the initial 1916 studies, and by adding 2 cross-references, 11 in vitro studies were included. Seven studies provide ultrastructural and/or chemical characterization, and six assessed microhardness and/or flexural strength. One percent to 8% sodium hypochlorite (NaOCl) and 1%-17% ethylenediaminetetraacetic acid (EDTA) were the most commonly tested solutions, with contact times of 2-240 min (NaOCl) and 1-1440 min (EDTA) being evaluated. CONCLUSIONS: Overall, the literature is consensual regarding the inevitable impact of NaOCl and chelating agents on coronal dentin, with both deproteinizing and decalcifying effects being concentration- and time-dependent. The alteration of mechanical parameters further confirmed the surface and subsurface ultrastructural and chemical changes. CLINICAL SIGNIFICANCE: Endodontic treatment success highly depends on restorative sealing. Understanding the result of exposing coronal dentin, the main substrate for bonding, to irrigants' action is crucial. The deproteinizing and decalcifying effects of NaOCl and chelating agents are both concentration- and time-dependent, causing surface and subsurface ultrastructural, chemical, and mechanical alterations.


Asunto(s)
Cavidad Pulpar , Dentina , Humanos , Ácido Edético/análisis , Ácido Edético/farmacología , Dentina/química , Irrigantes del Conducto Radicular/análisis , Irrigantes del Conducto Radicular/farmacología , Quelantes/análisis , Quelantes/farmacología
8.
Trop Anim Health Prod ; 56(4): 126, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38625501

RESUMEN

The objective of this study was to compare the indirect methods of obtaining digestibility with the direct method of total fecal collection to estimate the apparent digestibility of nutrients in sheep and goats supplemented with non-protein nitrogen. Five goats and five sheep with no defined racial pattern were used, distributed in two 5 × 5 Latin squares, with split plots, considering the diets as plots and the apparent digestibility determination methodologies as subplots. The diets were composed of buffelgrass hay and the addition, via ruminal infusion, of increasing amounts of nitrogen supplementation in order to gradually raise the CP level of the basal diet in intervals of 2% points, that is, + 2, +4, + 6 and + 8%. Samples of the feeds offered, and the leftovers were collected daily during the five days of collection to determine the nutrient intake, as well as the total collection of feces to determine the apparent digestibility of the nutrients. The amount of fecal dry matter excreted was estimated by the concentration of Indigestible Acid Detergent Fiber (ADFi), Indigestible Neutral Detergent Fiber (NDFi), Indigestible Dry Matter at 244 h (DMi 244 h) and Indigestible Dry Matter at 264 h (DMi 264 h). Among the evaluated markers, DMi 264 h had the lowest accuracy in estimating fecal excretion and nutrient digestibility. For the goat species, the markers ADFi and DMi 244 h proved to be able to adequately predict fecal excretion and digestibility indices, while NDFi stood out for both species. Among the evaluated markers, NDFi is the one that most accurately estimates the nutrient digestibility of the diet for goats and sheep.


Asunto(s)
Detergentes , Cabras , Animales , Ovinos , Nutrientes , Suplementos Dietéticos , Nitrógeno
9.
Stroke ; 54(7): 1708-1717, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37222709

RESUMEN

BACKGROUND: The optimal management of patients with isolated posterior cerebral artery occlusion is uncertain. We compared clinical outcomes for endovascular therapy (EVT) versus medical management (MM) in patients with isolated posterior cerebral artery occlusion. METHODS: This multinational case-control study conducted at 27 sites in Europe and North America included consecutive patients with isolated posterior cerebral artery occlusion presenting within 24 hours of time last well from January 2015 to August 2022. Patients treated with EVT or MM were compared with multivariable logistic regression and inverse probability of treatment weighting. The coprimary outcomes were the 90-day modified Rankin Scale ordinal shift and ≥2-point decrease in the National Institutes of Health Stroke Scale. RESULTS: Of 1023 patients, 589 (57.6%) were male with median (interquartile range) age of 74 (64-82) years. The median (interquartile range) National Institutes of Health Stroke Scale was 6 (3-10). The occlusion segments were P1 (41.2%), P2 (49.2%), and P3 (7.1%). Overall, intravenous thrombolysis was administered in 43% and EVT in 37%. There was no difference between the EVT and MM groups in the 90-day modified Rankin Scale shift (aOR, 1.13 [95% CI, 0.85-1.50]; P=0.41). There were higher odds of a decrease in the National Institutes of Health Stroke Scale by ≥2 points with EVT (aOR, 1.84 [95% CI, 1.35-2.52]; P=0.0001). Compared with MM, EVT was associated with a higher likelihood of excellent outcome (aOR, 1.50 [95% CI, 1.07-2.09]; P=0.018), complete vision recovery, and similar rates of functional independence (modified Rankin Scale score, 0-2), despite a higher rate of SICH and mortality (symptomatic intracranial hemorrhage, 6.2% versus 1.7%; P=0.0001; mortality, 10.1% versus 5.0%; P=0.002). CONCLUSIONS: In patients with isolated posterior cerebral artery occlusion, EVT was associated with similar odds of disability by ordinal modified Rankin Scale, higher odds of early National Institutes of Health stroke scale improvement, and complete vision recovery compared with MM. There was a higher likelihood of excellent outcome in the EVT group despite a higher rate of symptomatic intracranial hemorrhage and mortality. Continued enrollment into ongoing distal vessel occlusion randomized trials is warranted.


Asunto(s)
Isquemia Encefálica , Procedimientos Endovasculares , Accidente Cerebrovascular , Humanos , Masculino , Anciano , Anciano de 80 o más Años , Femenino , Isquemia Encefálica/terapia , Trombectomía , Estudios de Casos y Controles , Arteria Cerebral Posterior/diagnóstico por imagen , Procedimientos Endovasculares/efectos adversos , Hemorragias Intracraneales/etiología , Resultado del Tratamiento
10.
Magn Reson Med ; 90(3): 1041-1052, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37183485

RESUMEN

PURPOSE: To develop and evaluate a 3D sector-wise golden-angle (3D-SWIG) profile ordering scheme for cardiovascular MR cine imaging that maintains high k-space uniformity after electrocardiogram (ECG) binning. METHOD: Cardiovascular MR (CMR) was performed at 1.5 T. A balanced SSFP pulse sequence was implemented with a novel 3D-SWIG radial ordering, where k-space was divided into wedges, and each wedge was acquired in a separate heartbeat. The high uniformity of k-space coverage after physiological binning can be used to perform functional imaging using a very short acquisition. The 3D-SWIG was compared with two commonly used 3D radial trajectories for CMR (i.e., double golden angle and spiral phyllotaxis) in numerical simulations. Free-breathing 3D-SWIG and conventional breath-held 2D cine were compared in patients (n = 17) referred clinically for CMR. Quantitative comparison was performed based on left ventricular segmentation. RESULTS: Numerical simulations showed that 3D-SWIG both required smaller steps between successive readouts and achieved better k-space sampling uniformity after binning than either the double golden angle or spiral phyllotaxis trajectories. In vivo evaluation showed that measurements of left ventricular ejection fraction calculated from a 48 heart-beat free-breathing 3D-SWIG acquisition were highly reproducible and agreed with breath-held 2D-Cartesian cine (mean ± SD difference of -3.1 ± 3.5% points). CONCLUSIONS: The 3D-SWIG acquisition offers a simple solution for highly improved k-space uniformity after physiological binning. The feasibility of the 3D-SWIG method is demonstrated in this study through whole-heart cine imaging during free breathing with an acquisition time of less than 1 min.


Asunto(s)
Corazón , Imagenología Tridimensional , Imagen por Resonancia Cinemagnética , Humanos , Electrocardiografía , Respiración , Corazón/diagnóstico por imagen , Frecuencia Cardíaca , Volumen Sistólico , Función Ventricular Izquierda
11.
Mol Psychiatry ; 27(5): 2485-2491, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35256746

RESUMEN

Genetic and environmental factors contribute to the etiology of Attention Deficit-Hyperactivity Disorder (ADHD). In this sense, the study of epigenetic mechanisms could contribute to the understanding of the disorder's neurobiology. Global DNA methylation (GMe) evaluated through 5-methylcytosine levels could be a promising epigenetic biomarker to capture long-lasting biological effects in response to environmental and hormonal changes. We conducted the first assessment of GMe levels in subjects with ADHD (n = 394) and its main comorbidities in comparison to populational controls (n = 390). Furthermore, given the high genetic contribution to ADHD (heritability of 80%), polygenic risk scores (PRS) were calculated to verify the genetic contribution to GMe levels in ADHD and the comorbidities associated with GMe levels. The GMe levels observed in patients were lower than controls (P = 1.1e-8), with women being significantly less globally methylated than men (P = 0.002). Regarding comorbidities, the presence of bipolar disorder (BD) among patients with ADHD was associated with higher methylation levels compared to patients with ADHD without BD (P = 0.031). The results did not change when pharmacological treatment was accounted for in the analyses. The ADHD and BD most predictive PRSs were negatively (P = 0.0064) and positively (P = 0.0042) correlated with GMe, respectively. This study is the first to report an association between GMe, ADHD, and its comorbidity with BD and associations between PRSs for specific psychiatric disorders and GMe. Our findings add to previous evidence that GMe may be a relevant piece in the psychiatric disorders' etiological landscape.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad , Trastorno Bipolar , Adulto , Trastorno por Déficit de Atención con Hiperactividad/complicaciones , Trastorno por Déficit de Atención con Hiperactividad/epidemiología , Trastorno por Déficit de Atención con Hiperactividad/genética , Trastorno Bipolar/complicaciones , Trastorno Bipolar/epidemiología , Trastorno Bipolar/genética , Comorbilidad , Metilación de ADN/genética , Femenino , Humanos , Masculino , Herencia Multifactorial/genética
12.
Neurol Sci ; 44(7): 2617-2619, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36862200

RESUMEN

Polymicrogyria (PMG) is a malformation of cortical development that occurs mostly in the perisylvian region bilaterally (60-70%), most often presenting with epilepsy. Unilateral cases are much rarer with hemiparesis being the predominant symptom. We report a case of a 71-year-old man with right perirolandic PMG with ipsilateral hypoplasia and contralateral hyperplasia of the brainstem, with only non-progressive left-sided mild spastic hemiparesis. This imaging pattern is thought to occur due to the normal process of withdrawal of the axons of the corticospinal tract (CST) connected to aberrant cortex, possibly with compensatory contralateral CST hyperplasia. However, the majority of cases is additionally present with epilepsy. We believe it is worthwhile to investigate imaging patterns of PMG with symptoms' correlation, particularly with the help of techniques such as advanced brain imaging to assist in the study of cortical development along with adaptive somatotopic organization of the cerebral cortex in MCD with possible clinical applications.


Asunto(s)
Epilepsia , Polimicrogiria , Masculino , Humanos , Anciano , Polimicrogiria/complicaciones , Polimicrogiria/diagnóstico por imagen , Polimicrogiria/patología , Hiperplasia/complicaciones , Hiperplasia/diagnóstico por imagen , Hiperplasia/patología , Corteza Cerebral/patología , Epilepsia/patología , Tronco Encefálico/diagnóstico por imagen , Paresia , Imagen por Resonancia Magnética
13.
J Esthet Restor Dent ; 35(1): 48-55, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36325593

RESUMEN

OBJECTIVE: To evaluate the effect of rubber dam isolation on shear bond strength of two different adhesive systems to enamel. MATERIALS AND METHODS: The mesial, distal, lingual, and vestibular enamel surfaces of thirty human third molars were prepared (total n = 120). A custom splint was made to fit a volunteer's maxilla, holding the specimens in place in the oral cavity. Four composite resin cylinders were bonded to each tooth with one of two bonding agents (OptiBond FL and Prime&Bond active) with or without rubber dam isolation. Shear bond strength was tested in a universal testing machine and failure modes were assessed. Significance level for statistical analyses was set at 5%. RESULTS: All pairwise comparisons revealed statistical differences (p < 0.05). The highest mean shear bond strength values were obtained in rubber dam experimental groups, regardless of the adhesive system. Group OptiBond FL with rubber dam presented the highest mean bond strength values. Fracture modes for specimens bonded without rubber dam isolation were adhesive and cohesive within enamel, while rubber dam experimental groups revealed only cohesive fractures. CONCLUSIONS: Absolute isolation with rubber dam increases bond strength to enamel, independent of the adhesive system. The three-step total-etch system OptiBond FL provided significantly higher bond strength values than Prime&Bond active under both experimental conditions. CLINICAL SIGNIFICANCE: Rubber dam isolation has a significant effect on bond strengths to enamel, independent of the adhesive system. Its application is, therefore, advised whenever adhesive procedures are performed. A filled three-step etch-and-rinse adhesive performed superiorly, with or without rubber dam isolation, when bonding to enamel compared to an isopropanol-based universal adhesive.


Asunto(s)
Recubrimiento Dental Adhesivo , Humanos , Dique de Goma , Cementos de Resina/química , Resinas Compuestas/química , Esmalte Dental , Ensayo de Materiales , Recubrimientos Dentinarios/química
14.
Bioprocess Biosyst Eng ; 45(11): 1889-1904, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36245012

RESUMEN

Flux balance analysis (FBA) is currently the standard method to compute metabolic fluxes in genome-scale networks. Several FBA extensions employing diverse objective functions and/or constraints have been published. Here we propose a hybrid semi-parametric FBA extension that combines mechanistic-level constraints (parametric) with empirical constraints (non-parametric) in the same linear program. A CHO dataset with 27 measured exchange fluxes obtained from 21 reactor experiments served to evaluate the method. The mechanistic constraints were deduced from a reduced CHO-K1 genome-scale network with 686 metabolites, 788 reactions and 210 degrees of freedom. The non-parametric constraints were obtained by principal component analysis of the flux dataset. The two types of constraints were integrated in the same linear program showing comparable computational cost to standard FBA. The hybrid FBA is shown to significantly improve the specific growth rate prediction under different constraints scenarios. A metabolically efficient cell growth feed targeting minimal byproducts accumulation was designed by hybrid FBA. It is concluded that integrating parametric and nonparametric constraints in the same linear program may be an efficient approach to reduce the solution space and to improve the predictive power of FBA methods when critical mechanistic information is missing.


Asunto(s)
Redes y Vías Metabólicas , Modelos Biológicos , Cricetinae , Animales , Cricetulus , Células CHO
15.
J Esthet Restor Dent ; 34(4): 641-649, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34897958

RESUMEN

OBJECTIVE: This study aims to evaluate and compare the film thickness obtained with a resin cement and two composite resins, preheated and/or ultrasonically vibrated, as luting agents. MATERIALS AND METHODS: One hundred and twenty-six (126) pairs of resin discs were randomly assigned to six experimental groups (n = 21) according to luting agent (Variolink Esthetic LC, IPS Empress Direct or Estelite Omega) and cementation technique (preheating at 68°C and/or ultrasonic vibration). Specimens were luted by applying a controlled force. Following sectioning and film thickness measurement through field emission gun scanning electron microscopy, statistical analysis was carried out considering a 5% significance level. RESULTS: Statistically significant lower film thickness was observed in Variolink Esthetic LC group when compared to all composite resin groups (p < 0.001), except IPS Empress Direct preheated and ultrasonically vibrated group (p = 0.073). IPS Empress Direct with ultrasonic vibration yielded statistically lower film thickness values than Estelite Omega groups, regardless of luting technique (p < 0.05). Ultrasonically vibrated Estelite Omega groups showed statistically lower film thickness values than solely preheated groups (p < 0.05). CONCLUSIONS: Both Variolink Esthetic LC and IPS Empress Direct preheated and ultrasonically vibrated provided the lowest film thickness. The addition of ultrasonic vibration during cementation proved to be effective in reducing film thickness of both tested composite resins. CLINICAL SIGNIFICANCE: The cementation technique will have variable results depending on the luting material. Adhesive cementation protocols with composite resins should mainly consider ultrasonic vibration, but also preheating, as strategies for reducing film thickness. The tested resin cement, alongside with IPS Empress Direct composite resin preheated and ultrasonically vibrated, provided the lowest film thickness among the tested materials and techniques.


Asunto(s)
Recubrimiento Dental Adhesivo , Cementos de Resina , Cementación , Resinas Compuestas , Recubrimiento Dental Adhesivo/métodos , Cementos Dentales , Porcelana Dental , Ensayo de Materiales , Propiedades de Superficie
16.
Public Health Nurs ; 39(4): 752-759, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-34935199

RESUMEN

OBJECTIVE: There is still a lack of health indicators for monitoring and evaluating health planning at the local level. In Portugal, local health plans (LHP) include a prioritized set of health priorities, which should be monitored and evaluated. This study is an example of a low-resource method to identify and reuse indicators for LHP monitoring and evaluation already collected for other purposes. DESIGN AND SAMPLE: A modified Delphi consensus method was applied, with three rounds of email rating questionnaires and a final meeting, between January 2018 and January 2019. The Delphi panel consisted of eight members from the Planning and Administration Group of the Espinho/Gaia Local Public Health Unit. MEASUREMENTS: Panelists were asked to assess the indicators' validity for monitoring diseases/determinants from a pre-selected list of potential binomials between 140 PHC indicators and 15 diseases/determinants. RESULTS: After four rounds, there was consensus in considering 141 binomials (34.0%) as appropriate, diabetes mellitus being the disease with more appropriate indicators. CONCLUSION: This study portrays the applicability of a commonly used, easy and low-resource method in a Portuguese Local Public Health Unit to select and reuse primary health care indicators for LHP monitoring and evaluation.


Asunto(s)
Planificación en Salud , Indicadores de Calidad de la Atención de Salud , Consenso , Técnica Delphi , Humanos , Encuestas y Cuestionarios
17.
Medicina (Kaunas) ; 58(1)2022 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-35056421

RESUMEN

Background and Objectives: Peri-implantitis treatment is still undefined. Regenerative treatment is expensive and technically demanding due to the need to handle biomaterials, membranes and different methodologies of decontamination. Resective treatment and implantoplasty might be a viable solution. This case series presents a 24 month retrospective observational study of 10 peri-implantitis patients treated with implantoplasty. Materials and Methods: In the present case series, 10 peri-implantitis patients (20 implants) were treated with a resective approach and implantoplasty. Previous to implantoplasty, all patients underwent non-surgical treatment. This surgery consisted in a full-thickness flap and implant surface exposure. The exposed non-osseointegrated implant body was submitted to implantoplasty. The flap was apically repositioned and sutured. Patients were accompanied for 24 months. Results: The mean initial probing depth (PD) (PD = 5.37 ± 0.86 mm), bleeding on probing (BoP = 0.12 ± 0.06%) and suppuration (Sup = 0.01 ± 0.01%) decreased significantly at the 12 month evaluation (PD = 2.90 ± 0.39 mm; BoP = 0.01 ± 0.01% and Sup = 0.00 ± 0.00%). Between the 12 and 24 month evaluations, there were no significant clinical changes (PD = 2.85 ± 0.45 mm; BoP = 0.01 ± 0.01% and Sup = 0.00 ± 0.00%). Mucosal recession (MR) had a significant increase between the baseline and the first 12 months (0.69 ± 0.99 mm vs. 1.96 ± 1.33 mm), but there were no significant changes between the 12th and 24th month (1.94 ± 1.48 mm). The success rate was 100% without implant fracture or loss. Conclusions: Resective surgery and implantoplasty might be a valid option in some specific peri-implantitis cases. Properly designed clinical trials are needed to confirm this possibility.


Asunto(s)
Periimplantitis , Humanos , Periimplantitis/cirugía , Índice Periodontal , Investigación , Colgajos Quirúrgicos
18.
Int J Qual Health Care ; 33(1)2021 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-33515245

RESUMEN

BACKGROUND: Clinical pharmacists have an important role in the intensive care unit (ICU) team but are scarce resources. Our aim was to evaluate the impact of on-site pharmacists on medical prescriptions in the ICU. METHODS: This is a retrospective, quasi-experimental, controlled before-after study in two ICUs. Interventions by pharmacists were evaluated in phase 1 (February to November 2016) and phase 2 (February to May 2017) in ICU A (intervention) and ICU B (control). In phase 1, both ICUs had a telepharmacy service in which medical prescriptions were evaluated and interventions were made remotely. In phase 2, an on-site pharmacist was implemented in ICU A, but not in ICU B. We compared the number of interventions that were accepted in phase 1 versus phase 2. RESULTS: During the study period, 8797/9603 (91.6%) prescriptions were evaluated, and 935 (10.6%) needed intervention. In phase 2, there was an increase in the proportion of interventions that were accepted by the physician in comparison to phase 1 (93.9% versus 76.8%, P < 0.001) in ICU A, but there was no change in ICU B (75.2% versus 73.9%, P = 0.845). CONCLUSION: An on-site pharmacist in the ICU was associated with an increase in the proportion of interventions that were accepted by physicians.


Asunto(s)
Servicio de Farmacia en Hospital , Médicos , Estudios Controlados Antes y Después , Humanos , Unidades de Cuidados Intensivos , Farmacéuticos , Estudios Retrospectivos
19.
Clin Oral Investig ; 25(5): 3131-3139, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33047203

RESUMEN

OBJECTIVES: The aim of this study was to evaluate the shear bond strength inherent to immediate and delayed definitive composite resin restorations, over three different biomaterials. METHODS: Fifty-four aluminum blocks were randomly assigned to six experimental groups (n = 9) according to the biomaterial (Biodentine, TotalFill BC Putty, or PCM) and restoration timing (immediate or 7 days delayed). Regarding the restorative procedures, a two-step self-etch bonding system (Clearfil SE Bond) was applied and subsequently restored using a flowable composite resin (SDR). After shear bond strength testing, fracture pattern analysis was performed. The significance level was set at α = 0.05. RESULTS: Within the immediate groups, Biodentine showed the highest mean shear bond strength value, with no statistically significant differences (P > 0.05) being detected when compared with both TotalFill (P = 0.072) and PCM (P = 0.232) groups. Regarding the delayed restoration groups, Biodentine and TotalFill presented the highest mean shear bond strength value, with statistical differences when compared with PCM (P = 0.002 and P = 0.043, respectively). No statistically significant differences (P > 0.05) were verified between both immediate and delayed groups for each tested biomaterial. Also, a statistically significant association was found between the fracture type and the biomaterial (P < 0.001). CONCLUSIONS AND CLINICAL RELEVANCE: Our findings suggest that all tested biomaterials present suitable alternatives which allow to perform restorative procedures immediately after pulp capping biomaterial placement (3 or 12 min, depending on the bioactive cement), therefore requiring one single appointment to complete the procedure. Biodentine and TotalFill BC Putty have shown superior shear bond strength results when compared with PCM, within a delayed timeframe (7 days).


Asunto(s)
Recubrimiento Dental Adhesivo , Cementos Dentales , Compuestos de Calcio , Resinas Compuestas , Análisis del Estrés Dental , Ensayo de Materiales , Cementos de Resina , Resistencia al Corte , Silicatos
20.
Sensors (Basel) ; 21(4)2021 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-33672605

RESUMEN

The demand for online services is increasing. Services that would require a long time to understand, use and master are becoming as transparent as possible to the users, that tend to focus only on the final goals. Combined with the advantages of the unmanned vehicles (UV), from the unmanned factor to the reduced size and costs, we found an opportunity to bring to users a wide variety of services supported by UV, through the Internet of Unmanned Vehicles (IoUV). Current solutions were analyzed and we discussed scalability and genericity as the principal concerns. Then, we proposed a solution that combines several services and UVs, available from anywhere at any time, from a cloud platform. The solution considers a cloud distributed architecture, composed by users, services, vehicles and a platform, interconnected through the Internet. Each vehicle provides to the platform an abstract and generic interface for the essential commands. Therefore, this modular design makes easier the creation of new services and the reuse of the different vehicles. To confirm the feasibility of the solution we implemented a prototype considering a cloud-hosted platform and the integration of custom-built small-sized cars, a custom-built quadcopter, and a commercial Vertical Take-Off and Landing (VTOL) aircraft. To validate the prototype and the vehicles' remote control, we created several services accessible via a web browser and controlled through a computer keyboard. We tested the solution in a local network, remote networks and mobile networks (i.e., 3G and Long-Term Evolution (LTE)) and proved the benefits of decentralizing the communications into multiple point-to-point links for the remote control. Consequently, the solution can provide scalable UV-based services, with low technical effort, for anyone at anytime and anywhere.

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