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1.
Am J Physiol Endocrinol Metab ; 326(5): E681-E695, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38597829

RESUMEN

Hypothalamic proopiomelanocortin (POMC) neurons are sensors of signals that reflect the energy stored in the body. Inducing mild stress in proopiomelanocortin neurons protects them from the damage promoted by the consumption of a high-fat diet, mitigating the development of obesity; however, the cellular mechanisms behind these effects are unknown. Here, we induced mild stress in a proopiomelanocortin neuron cell line by inhibiting Crif1. In proopiomelanocortin neurons exposed to high levels of palmitate, the partial inhibition of Crif1 reverted the defects in mitochondrial respiration and ATP production; this was accompanied by improved mitochondrial fusion/fission cycling. Furthermore, the partial inhibition of Crif1 resulted in increased reactive oxygen species production, increased fatty acid oxidation, and reduced dependency on glucose for mitochondrial respiration. These changes were dependent on the activity of CPT-1. Thus, we identified a CPT-1-dependent metabolic shift toward greater utilization of fatty acids as substrates for respiration as the mechanism behind the protective effect of mild stress against palmitate-induced damage of proopiomelanocortin neurons.NEW & NOTEWORTHY Saturated fats can damage hypothalamic neurons resulting in positive energy balance, and this is mitigated by mild cellular stress; however, the mechanisms behind this protective effect are unknown. Using a proopiomelanocortin cell line, we show that under exposure to a high concentration of palmitate, the partial inhibition of the mitochondrial protein Crif1 results in protection due to a metabolic shift warranted by the increased expression and activity of the mitochondrial fatty acid transporter CPT-1.


Asunto(s)
Carnitina O-Palmitoiltransferasa , Proteínas de Ciclo Celular , Ácidos Grasos , Mitocondrias , Animales , Ratones , Carnitina O-Palmitoiltransferasa/metabolismo , Carnitina O-Palmitoiltransferasa/genética , Línea Celular , Ácidos Grasos/metabolismo , Hipotálamo/metabolismo , Hipotálamo/efectos de los fármacos , Mitocondrias/metabolismo , Mitocondrias/efectos de los fármacos , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Proopiomelanocortina/metabolismo , Proopiomelanocortina/genética , Especies Reactivas de Oxígeno/metabolismo , Proteínas de Ciclo Celular/antagonistas & inhibidores , Proteínas de Ciclo Celular/metabolismo
2.
Ecotoxicology ; 33(1): 104-118, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38236330

RESUMEN

Aquatic organisms are exposed to several compounds that occur in mixtures in the environment. Thus, it is important to investigate their impacts on organisms because these combined effects can be potentiated. Cobalt (Co) and nickel (Ni) are metals that occur in the environment and are used in human activities. To the best of our knowledge, there are no studies that investigated the combined effects of these metals on a freshwater Chlorophyceae. Therefore, this study analyzed the isolated and combined effects of Co and Ni in cell density, physiological and morphological parameters, reactive oxygen species (ROS), carbohydrates and photosynthetic parameters of the microalga Raphidocelis subcapitata. Data showed that Co affected the cell density from 0.25 mg Co L-1; the fluorescence of chlorophyll a (Chl a) (0.10 mg Co L-1); ROS production (0.50 mg Co L-1), total carbohydrates and efficiency of the oxygen evolving complex (OEC) at all tested concentrations; and the maximum quantum yield (ΦM) from 0.50 mg Co L-1. Ni exposure decreased ROS and cell density (0.35 mg Ni L-1); altered Chl a fluorescence and carbohydrates at all tested concentrations; and did not alter photosynthetic parameters. Regarding the Co-Ni mixtures, our data best fitted the concentration addition (CA) model and dose-ratio dependent (DR) deviation in which synergism was observed at low doses of Co and high doses of Ni and antagonism occurred at high doses of Co and low doses of Ni. The combined metals affected ROS production, carbohydrates, ΦM, OEC and morphological and physiological parameters.


Asunto(s)
Chlorophyceae , Microalgas , Contaminantes Químicos del Agua , Humanos , Níquel/toxicidad , Clorofila A/farmacología , Cobalto/toxicidad , Especies Reactivas de Oxígeno , Metales , Carbohidratos/farmacología , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/análisis
3.
Artículo en Portugués | MEDLINE | ID: mdl-38226153

RESUMEN

Objective: To perform a systematic review of scientific publications addressing the use of stratification methods to define risk areas for measles transmission. Method: Articles published in English, Portuguese, and Spanish in journals indexed in the SciELO, PubMed, and LILACS databases were selected. The search terms risk assessment AND measles were used without date limits. Editorials, opinion articles, individual-level observational studies, and publications that did not focus on the application of methods to stratify measles transmission risk areas were excluded. Year of publication, authorship, country where the study was performed, objective, geographic level of analysis, method used, indicators, and limitations were recorded in a data form. Results: Thirteen articles published between 2011 and 2022 in nine countries from the six World Health Organization (WHO) regions were selected. Of these, 10 referred to the Measles Risk Assessment Tool developed by the WHO/Centers for Disease Control and Prevention. Only one study adapted the tool to the local context. The risk stratification indicators used in the selected studies focused on a combination of the following dimensions: population immunity, quality of surveillance systems, and epidemiologic status. The systematic output of data with adequate quality and coverage was a noteworthy aspect hindering risk stratification. Conclusion: There seems to be limited dissemination of measles risk stratification strategies, especially at local levels. The need to train human resources to process and interpret risk analyses as part of the routine of surveillance services is emphasized.


Objetivo: Realizar una revisión sistemática de las publicaciones científicas en las que se han abordado experiencias de aplicación de métodos de estratificación para definir las zonas de riesgo de transmisión del sarampión. Métodos: Se seleccionaron artículos publicados en español, inglés o portugués en revistas indizadas en las bases de datos SciELO, PubMed y LILACS. En la búsqueda se utilizaron los descriptores "risk assessment" y "measles", sin limitaciones en la fecha de publicación. Se excluyeron editoriales, artículos de opinión, estudios de observación de pacientes individuales y publicaciones que no tratasen de la aplicación de métodos de estratificación de zonas de riesgo de transmisión del sarampión. Se empleó un formulario para extraer la información sobre año de publicación, autoría, país de realización del estudio, objetivo, escala geográfica, método utilizado, indicadores y limitaciones. Resultados: Se seleccionaron 13 artículos publicados entre el 2011 y el 2022 en nueve países de las seis regiones de la Organización Mundial de la Salud (OMS). En 10 de ellos se utilizó como referencia la herramienta de evaluación del riesgo de sarampión creada por la OMS y los Centros para el Control y la Prevención de Enfermedades de Estados Unidos. Solamente en un estudio se adaptó la herramienta al contexto local. Los indicadores utilizados para la estratificación del riesgo se basaron en una combinación de las dimensiones de inmunidad poblacional, calidad de los sistemas de vigilancia y situación epidemiológica. Entre las dificultades de la estratificación del riesgo se destaca la de generación sistemática de datos con una cobertura y calidad adecuadas. Conclusión: Las estrategias de estratificación del riesgo de transmisión del sarampión siguen sin estar, al parecer, muy extendidas, en especial a nivel local. Cabe reiterar la necesidad de fomentar la capacitación de recursos humanos para procesar e interpretar los análisis de riesgo en las operaciones habituales de los servicios de vigilancia.

4.
J Oral Rehabil ; 51(3): 517-525, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37941125

RESUMEN

BACKGROUND: There is no established protocol for the low doses of cone-beam computed tomography (CBCT) acquisition and filter application on the diagnosis of condylar morphological alterations. OBJECTIVES: The objective of the study was to evaluate the influence of voxel size and filter application on the diagnosis of condylar morphological alterations in CBCT using an ex vivo model. METHODS: CBCT scans of 36 temporomandibular joints were acquired using OP300 Maxio with voxel sizes of 0.085, 0.125 and 0.280 mm. Three radiologists evaluated the condyles in the CBCT volumes under three filter modes: no filter, '1x' sharpen filter and '2x' sharpen filter. The area under the ROC curve, sensitivity and specificity were calculated by comparing the evaluators' responses with the reference standard and compared among experimental groups using analysis of variance (ANOVA) (α = 5%). RESULTS: The area under the ROC curve, sensitivity and specificity were not affected by voxel size and filter application (p > .05). For osteophyte and flattening, there were more true-positive responses in smaller voxel size. For erosion, the increase of true- and false-positive responses occurred with a larger voxel size. Overall, there was a tendency to decrease true positives for osteophyte and erosion and increase false positives for flattening with the '2x' sharpen filter. CONCLUSIONS: The diagnosis of condylar morphological alterations assessed in this ex vivo analysis is not influenced by the voxel size and the application of the filters. However, attention is needed with the occurrence of false-positive diagnosis with a larger voxel size for erosion and '2x' sharpen filter for flattening.


Asunto(s)
Osteofito , Tomografía Computarizada de Haz Cónico Espiral , Humanos , Sensibilidad y Especificidad , Tomografía Computarizada de Haz Cónico/métodos , Huesos
5.
J Oral Rehabil ; 50(1): 1-11, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36271700

RESUMEN

BACKGROUND: There is no established acquisition protocol based on scientific evidence for the acquisition of cone-beam computed tomography (CBCT) exams to evaluate the temporomandibular joint (TMJ). OBJECTIVES: To evaluate the influence of acquisition protocols and jaw positioning on the diagnostic accuracy of TMJ condylar morphological alterations (CMA), dimension, position and excursion. METHODS: Thirty-six TMJs on 18 dry skulls were imaged using a CBCT unit (OP300 Maxio, Instrumentarium, Tuusula, Finland) at two exposure settings (4.5 and 6.3 mA), three voxel resolutions (0.085, 0.125 and 0.280 mm), three jaw positions (concentric, anteriorised and posteriorised) and three jaw excursions (normoexcursion, hyperexcursion and hypoexcursion). The macroscopic anatomy examination and high-resolution CBCT images were used as ground truth for CMA. Twenty-five TMJs had at least one CMA with 11 healthy TMJs serving as controls. Three experienced oral and maxillofacial radiologists evaluated the parasagittal images for the presence of CMA, position and excursion and measured dimensions. The area under the ROC curve, sensitivity and specificity were calculated. Weighted Kappa (α = 0.05) was used to determine intra- and interexaminer reliability and comparisons between dependent variables analysed by Analysis of Variance at an a prior level of significance of 0.05. RESULTS: The agreement of the evaluation of the position and excursion with the reference standard was high, independent of the protocol (range, 0.75-0.91). Various combinations of acquisition protocols and jaw position did not influence the CMA evaluation. Erosion was overdiagnosed in protocols with larger voxel sizes and the detection of osteophytes greater in images with smaller voxel sizes. The anteroposterior dimension was greater in the open jaw position (p < .05). CONCLUSION: CBCT protocols using reduced radiation exposure from the CBCT machine evaluated in this study can be used to assess condylar morphology, dimension, position and excursion, without compromising diagnostic performances for these parameters.


Asunto(s)
Trastornos de la Articulación Temporomandibular , Humanos , Trastornos de la Articulación Temporomandibular/diagnóstico por imagen , Reproducibilidad de los Resultados , Articulación Temporomandibular/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico/métodos , Sensibilidad y Especificidad
6.
Artículo en Inglés | MEDLINE | ID: mdl-36966237

RESUMEN

This systematic review provides a comprehensive assessment of risk factors related to early sexual intercourse (ESI) among adolescents. We used PRISMA guidelines to identify eligible cohort studies published between January 1999 and December 2020. We searched on three databases: PubMed, Embase and LILACS. Studies were screened for quality and eligibility. Of 2787 identified studies, seven met our inclusion criteria. The studies examined a range of factors, which were organized into four dimensions - individual, family, social and environmental, and sociodemographic. Risk factors with strong associations for ESI were: adolescent and parental substance use, aggression and conduct disorders, family attachment, school achievement, family living situation, and maternal education. Three studies were birth cohorts. This review demonstrates the important roles of substance use, family attachment and academic factors in shaping adolescents' sexual behavior. A strength of this review is its focus on longitudinal studies, enabling exploration of exposures collected before initiation of sexual intercourse.

7.
J Environ Manage ; 335: 117539, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-36841003

RESUMEN

The achievement of the Sustainable Development Goals is being pursued worldwide. While energy production and consumption are to be oriented towards renewable energies, ecologically and socially sustainable agriculture is also a target for science and society. Due to the expansion of renewable energies, agricultural land in particular is the focus of various interest groups, from food production to energy production. In this interdisciplinary study, we show the opportunities and limits of joint synergies from the nexus of food production, energy production, energy consumption, biodiversity protection and social acceptance of renewable energies in a scenario. Biodiversity agriphotovoltaics, i.e. agriphotovoltaics in combination with biodiversity protection measures, such as flower strips, can make a valuable contribution to promoting biotope connectivity in addition to significant energy production. We show this in a GIS-based regional assessment for Lower Saxony in northern Germany. This rough spatial assessment is followed by a modelling of energy production and consumption during the cultivation of a characteristic agricultural field in the loess region of Lower Saxony. Our focus here is on the possibilities of using cable electricity or battery storage for carrying out the cultivation. In an accompanying survey of farmers regarding the use of agriphotovoltaics, we collected and evaluated their prior knowledge, experiences, and attitudes towards this technology. Finally, we show which advantages agriphotovoltaics and electrified agricultural machinery can also have for the sustainable transformation of agriculture and which challenges exist for a truly sustainable use of these technologies.


Asunto(s)
Agricultura , Conservación de los Recursos Naturales , Biodiversidad , Desarrollo Sostenible , Tecnología
8.
Clin Oral Investig ; 26(2): 1199-1215, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34800204

RESUMEN

OBJECTIVE: To determine the prevalence of the elongated styloid process (ESP) and its characteristics, such as sex and age of the patient, unilateral and bilateral incidence, besides variations between different populations and panoramic and CBCT examinations. MATERIALS AND METHODS: A search was performed in six databases (PubMed, Web of Science, Scopus, Cochrane, Lilacs, and Embase) to identify observational studies that used imaging exams and assessed ESP prevalence among panoramic radiograph CBCT examinations, whose transversal prevalence studies were included. Furthermore, studies with a specific group of patients or symptomatic patients were excluded. Additionally, Joanna Briggs Institute checklist was used to evaluate the quality of the studies. A meta-analysis was conducted, then subgroup analyses were performed by grouping studies according to the secondary outcomes, with a significance level set at 5%. The Grading of Recommendations Assessment, Development, and Evaluation system was used to rate the certainty in the evidence. RESULTS: The initial search resulted in 1635 studies, from which 39 articles met the inclusion criteria, encompassing 50,655 participants. The sample size varied between 82 and 5,000 participants. The prevalence of the ESP ranged from 1.3 to 94.8%, with an overall prevalence of 30.2%. The bilateral occurrence was higher than the unilateral one, but no significant predilection was observed according to sex, age, or population. The type of imaging examination also showed no difference in its detection. CONCLUSION: The overall prevalence of ESP was 30.2%, with a propensity for bilaterality, but not for any sex, age, or population geographic location. The imaging examination modality did not influence the diagnosis of ESP. However, the quality level of the studies evaluated was very low, demonstrating the need for more homogeneous primary studies on the prevalence of the ESP with a more standardized methodology. CLINICAL RELEVANCE: There is no consensus in the literature regarding the prevalence of the ESP and the characteristics of the affected patients that can cause chronic and debilitating discomfort in the head and neck region. Therefore, knowledge about the prevalence and characteristics of this condition would help dental clinicians reach the correct diagnosis.


Asunto(s)
Osificación Heterotópica , Humanos , Prevalencia , Radiografía Panorámica , Hueso Temporal/anomalías , Hueso Temporal/diagnóstico por imagen
9.
Clin Oral Investig ; 26(1): 159-169, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34050829

RESUMEN

OBJECTIVES: The aim of this study was to evaluate the mandibular condyles of neurofibromatosis 1 (NF1) individuals without facial plexiform neurofibroma using cone beam computed tomography images. MATERIALS AND METHODS: Eighty cone beam computed tomography scans (160 mandibular condyles) were analyzed: 40 from NF1 individuals (study group) and 40 from individuals without NF1 (control group). The anteroposterior and mediolateral dimensions, height, and volume of the mandibular condyles were measured. The mandibular condyles were classified according to their morphology: healthy (absence of morphological changes), with flattening (loss of rounded contour of at least one of the surfaces), with erosion (loss of continuity of the cortical bone), with osteophyte (exophytic formation of the condyle surface), and with sclerosis (any increase in the cortical thickness in the load-bearing areas). Furthermore, the position of the mandibular condyles in relation to the joint fossa in an anteroposterior view was classified as anterior, concentric, or posterior. RESULTS: The study group had a higher anteroposterior dimension of the mandibular condyles compared with the control group (p < 0.05). There were no differences in condylar morphology and position between both groups (p > 0.05). The morphological alterations were not associated with sex or age in any group evaluated (p > 0.05). For both groups, the concentric position was the most common. For the study group, there was a significant difference in the condylar position between the sides (p < 0.05). CONCLUSIONS: NF1 individuals without facial plexiform neurofibroma present a high prevalence of condyles with a large anteroposterior dimension and asymmetric position in the joint fossa. However, no morphological and volumetric changes were observed in the mandibular condyles of them. CLINICAL RELEVANCE: The knowledge of the TMJ alterations in individuals with NF1 is important to establish an evaluation protocol, which would allow early intervention if indicated.


Asunto(s)
Cóndilo Mandibular , Neurofibromatosis 1 , Estudios de Casos y Controles , Tomografía Computarizada de Haz Cónico , Humanos , Cóndilo Mandibular/diagnóstico por imagen , Neurofibromatosis 1/diagnóstico por imagen , Articulación Temporomandibular
10.
J Pharmacol Exp Ther ; 376(1): 51-63, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33115824

RESUMEN

Asthma is still an incurable disease, and there is a recognized need for novel small-molecule therapies for people with asthma, especially those poorly controlled by current treatments. We previously demonstrated that calcium-sensing receptor (CaSR) negative allosteric modulators (NAMs), calcilytics, uniquely suppress both airway hyperresponsiveness (AHR) and inflammation in human cells and murine asthma surrogates. Here we assess the feasibility of repurposing four CaSR NAMs, which were originally developed for oral therapy for osteoporosis and previously tested in the clinic as a novel, single, and comprehensive topical antiasthma therapy. We address the hypotheses, using murine asthma surrogates, that topically delivered CaSR NAMs 1) abolish AHR; 2) are unlikely to cause unwanted systemic effects; 3) are suitable for topical application; and 4) inhibit airway inflammation to the same degree as the current standard of care, inhaled corticosteroids, and, furthermore, inhibit airway remodeling. All four CaSR NAMs inhibited poly-L-arginine-induced AHR in naïve mice and suppressed both AHR and airway inflammation in a murine surrogate of acute asthma, confirming class specificity. Repeated exposure to inhaled CaSR NAMs did not alter blood pressure, heart rate, or serum calcium concentrations. Optimal candidates for repurposing were identified based on anti-AHR/inflammatory activities, pharmacokinetics/pharmacodynamics, formulation, and micronization studies. Whereas both inhaled CaSR NAMs and inhaled corticosteroids reduced airways inflammation, only the former prevented goblet cell hyperplasia in a chronic asthma model. We conclude that inhaled CaSR NAMs are likely a single, safe, and effective topical therapy for human asthma, abolishing AHR, suppressing airways inflammation, and abrogating some features of airway remodeling. SIGNIFICANCE STATEMENT: Calcium-sensing receptor (CaSR) negative allosteric modulators (NAMs) reduce airway smooth muscle hyperresponsiveness, reverse airway inflammation as efficiently as topical corticosteroids, and suppress airway remodeling in asthma surrogates. CaSR NAMs, which were initially developed for oral therapy of osteoporosis proved inefficacious for this indication despite being safe and well tolerated. Here we show that structurally unrelated CaSR NAMs are suitable for inhaled delivery and represent a one-stop, steroid-free approach to asthma control and prophylaxis.


Asunto(s)
Antiasmáticos/uso terapéutico , Asma/tratamiento farmacológico , Indanos/uso terapéutico , Naftalenos/uso terapéutico , Fenilpropionatos/uso terapéutico , Quinazolinonas/uso terapéutico , Receptores Sensibles al Calcio/agonistas , Regulación Alostérica , Animales , Antiasmáticos/efectos adversos , Antiasmáticos/farmacología , Bronquios/efectos de los fármacos , Bronquios/metabolismo , Reposicionamiento de Medicamentos , Células HEK293 , Humanos , Indanos/efectos adversos , Indanos/farmacología , Masculino , Ratones , Ratones Endogámicos BALB C , Naftalenos/efectos adversos , Naftalenos/farmacología , Fenilpropionatos/efectos adversos , Fenilpropionatos/farmacología , Quinazolinonas/efectos adversos , Quinazolinonas/farmacología , Receptores Sensibles al Calcio/metabolismo
11.
Pharm Res ; 38(2): 277-288, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33575958

RESUMEN

PURPOSE: Computational Fluid Dynamics (CFD) simulations are performed to investigate the impact of adding a grid to a two-inlet dry powder inhaler (DPI). The purpose of the paper is to show the importance of the correct choice of closure model and modeling approach, as well as to perform validation against particle dispersion data obtained from in-vitro studies and flow velocity data obtained from particle image velocimetry (PIV) experiments. METHODS: CFD simulations are performed using the Ansys Fluent 2020R1 software package. Two RANS turbulence models (realisable k - ε and k - ω SST) and the Stress Blended Eddy Simulation (SBES) models are considered. Lagrangian particle tracking for both carrier and fine particles is also performed. RESULTS: Excellent comparison with the PIV data is found for the SBES approach and the particle tracking data are consistent with the dispersion results, given the simplicity of the assumptions made. CONCLUSIONS: This work shows the importance of selecting the correct turbulence modelling approach and boundary conditions to obtain good agreement with PIV data for the flow-field exiting the device. With this validated, the model can be used with much higher confidence to explore the fluid and particle dynamics within the device.


Asunto(s)
Administración por Inhalación , Aerosoles/química , Inhaladores de Polvo Seco , Diseño de Equipo , Polvos/química , Química Farmacéutica , Simulación por Computador , Hidrodinámica , Modelos Químicos , Tamaño de la Partícula , Reología
12.
Arch Sex Behav ; 50(6): 2371-2382, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34318392

RESUMEN

Sexual risk behaviors are closely related to the use of alcohol, tobacco, and other illicit drugs as well as teen dating violence. School-based drug prevention programs that teach social and personal skills could potentially also reduce sexual risk behaviors. We examined the effects of the #Tamojunto program on youth sexual risk behaviors. A randomized controlled trial was conducted with 6391 7th and 8th grade students in 72 public schools in six Brazilian cities. Baseline data were collected prior to program implementation. Two waves of follow-up assessments occurred after 9 and 21 months. Analyses were performed taking into account the multilevel structure of the data. We used intention-to-treat to evaluate changes in the prevalence of sexual risk behaviors over time and between groups. Adolescent age ranged from 11 to 15 years, with a mean of 12.6 ± 0.8 years, and 51.0% were female. Among all participants, receipt of #Tamojunto was associated with higher risk of lifetime sex at 21 months follow-up (OR 1.27, 95% CI [1.03, 1.56]). Among girls, at 9 months follow-up, the program was associated with higher likelihood of having engaged in sex in the last month (OR 1.76, 95% CI [1.13, 2.74]). At 21 months follow-up, girls receiving the program were more likely to report engaging in condomless sex in the last month (OR 1.64, 95% CI [1.07, 2.50]). #Tamojunto may be ineffective and possibly harmful for preventing sexual risk behaviors, especially among girls. We suggest further investigation of the possible mediating role of life skills intervention components on girl's sexual behaviors.


Asunto(s)
Conducta del Adolescente , Preparaciones Farmacéuticas , Adolescente , Niño , Femenino , Humanos , Asunción de Riesgos , Servicios de Salud Escolar , Instituciones Académicas , Conducta Sexual
13.
Int Endod J ; 54(10): 1769-1781, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34003491

RESUMEN

BACKGROUND: The effectiveness of the metal artefact reduction (MAR) tool for the detection of vertical root fracture (VRF) by cone beam computed tomography (CBCT) images is controversial. OBJECTIVE: To evaluate the effectiveness of the MAR tool on VRF detection involving teeth with intracanal materials in CBCT images. METHODOLOGY: In September 2019, an electronic search was performed in six databases (PubMed, Scopus, Web of Science, Cochrane, Lilacs and Embase). The electronic search was updated in May 2020 through searches in Google Scholar and references of included studies (embracing the electronic and gray literature searches). No language or year restrictions were applied. Independently, two reviewers examined titles, abstracts and full texts according to the eligibility criteria that were as follows: diagnostic studies that evaluated the effectiveness of the MAR tool on the diagnosis of VRF in human teeth (laboratory or in vivo studies) on CBCT images. The risk of bias was evaluated using the Quality Assessment Tool for Diagnostic of Accuracy Studies-2 (QUADAS-2). For conducting the meta-analysis, the values of sensitivity, specificity, diagnostic odds ratio (DOR) and area under the ROC curve (AUC) were obtained, considering the subgroups with and without MAR active. The Grading of Recommendation, Assessment, Development and Evaluation instrument was applied to assess the level of evidence across the studies using GRADEpro software. RESULTS: A total of 8 laboratory studies were included in both systematic review and meta-analysis. The values of sensitivity, specificity, DOR and AUC to VRF diagnosis with and without MAR active were, respectively, 0.586 and 0.603; 0.699 and 0.713, 3.037 and 3.767; 0.67 and 0.71. The quality of the evidence suggested low confidence in estimating the outcomes. DISCUSSION: The MAR tool decreased slightly the diagnostic values of VRF involving teeth with intracanal materials in laboratory studies. However, it is important to highlight that most studies had an uncertain risk of bias. CONCLUSIONS: Although a low level of evidence and high heterogeneity were observed in the included studies, the meta-analysis revealed better diagnosis values for VRF detection when the MAR was deactivated when analysing extracted teeth in a laboratory setting. REGISTRATION: PROSPERO-CRD42020145222. FUNDING: This study was financed in party by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior-Brasil (CAPES).


Asunto(s)
Fracturas de los Dientes , Diente no Vital , Artefactos , Tomografía Computarizada de Haz Cónico , Humanos , Fracturas de los Dientes/diagnóstico por imagen , Raíz del Diente
14.
Ecotoxicol Environ Saf ; 208: 111628, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396148

RESUMEN

Metals may cause damage to the biota of contaminated environments. Moreover, using multiple endpoints in ecotoxicological studies is useful to better elucidate the mechanisms of toxicity of these compounds. Therefore, this study aimed to evaluate the effects of cadmium (Cd) and cobalt (Co) on growth, biochemical and photosynthetic parameters of the microalgae Raphidocelis subcapitata, through quantification of lipid classes composition, chlorophyll a (Chl a) content, maximum (ΦM) and effective (Φ'M) quantum yields and efficiency of the oxygen-evolving complex (OEC). Both metals affected the algal population growth, with an IC50-96h of 0.67 and 1.53 µM of Cd and Co, respectively. Moreover, the metals led to an increase in the total lipid content and reduced efficiency of OEC and ΦM. Cell density was the most sensitive endpoint to detect Cd toxicity after 96 h of treatment. Regarding Co, the photosynthetic parameters were the most affected and the total lipid content was the most sensitive endpoint as it was altered by the exposure to this metal in all concentrations. Cd led to increased contents of the lipid class wax esters (0.89 µM) and phospholipids (PL - at 0.89 and 1.11 µM) and decreased values of triglycerides (at 0.22 µM) and acetone-mobile polar lipids (AMPL - at 0.44 and 1.11 µM). The percentage of free fatty acids (FFA) and PL of microalgae exposed to Co increased, whereas AMPL decreased in all concentrations tested. We were able to detect differences between the toxicity mechanisms of each metal, especially how Co interferes in the microalgae at a biochemical level. Furthermore, to the best of our knowledge, this is the first study reporting Co effects in lipid classes of a freshwater Chlorophyceae. The damage caused by Cd and Co may reach higher trophic levels, causing potential damage to the aquatic communities as microalgae are primary producers and the base of the food chain.


Asunto(s)
Cadmio/toxicidad , Chlorophyceae/fisiología , Cobalto/toxicidad , Contaminantes Químicos del Agua/toxicidad , Chlorophyceae/efectos de los fármacos , Clorofila A , Ecotoxicología , Agua Dulce/química , Metales/farmacología , Microalgas/efectos de los fármacos , Fotosíntesis/efectos de los fármacos , Complejo de Proteína del Fotosistema II
15.
Genet Mol Biol ; 44(2): e20200014, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33821877

RESUMEN

Tuberous sclerosis complex (TSC) is an autosomal dominant genetic disorder caused by germline mutations in TSC1 or TSC2 genes, which leads to the hyperactivation of the mTORC1 pathway, an important negative regulator of autophagy. This leads to the development of hamartomas in multiple organs. The variability in symptoms presents a challenge for the development of completely effective treatments for TSC. One option is the treatment with mTORC1 inhibitors, which are targeted to block cell growth and restore autophagy. However, the therapeutic effect of rapamycin seems to be more efficient in the early stages of hamartoma development, an effect that seems to be associated with the paradoxical role of autophagy in tumor establishment. Under normal conditions, autophagy is directly inhibited by mTORC1. In situations of bioenergetics stress, mTORC1 releases the Ulk1 complex and initiates the autophagy process. In this way, autophagy promotes the survival of established tumors by supplying metabolic precursors during nutrient deprivation; paradoxically, excessive autophagy has been associated with cell death in some situations. In spite of its paradoxical role, autophagy is an alternative therapeutic strategy that could be explored in TSC. This review compiles the findings related to autophagy and the new therapeutic strategies targeting this pathway in TSC.

16.
Genet Mol Biol ; 44(4): e20200475, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34609442

RESUMEN

Tuberous sclerosis complex (TSC) is an autosomal dominant cancer predisposition disorder caused by heterozygous mutations in TSC1 or TSC2 genes and characterized by mTORC1 hyperactivation. TSC-associated tumors develop after loss of heterozygosity mutations and their treatment involves the use of mTORC1 inhibitors. We aimed to evaluate cellular processes regulated by mTORC1 in TSC cells with different mutations before tumor development. Flow cytometry analyses were performed to evaluate cell viability, cell cycle and autophagy in non-tumor primary TSC cells with different heterozygous mutations and in control cells without TSC mutations, before and after treatment with rapamycin (mTORC1 inhibitor). We did not observe differences in cell viability and cell cycle between the cell groups. However, autophagy was reduced in mutated cells. After rapamycin treatment, mutated cells showed a significant increase in the autophagy process (p=0.039). We did not observe differences between cells with distinct TSC mutations. Our main finding is the alteration of autophagy in non-tumor TSC cells. Previous studies in literature found autophagy alterations in tumor TSC cells or knock-out animal models. We showed that autophagy could be an important mechanism that leads to TSC tumor formation in the haploinsufficiency state. This result could guide future studies in this field.

17.
J Biol Chem ; 294(24): 9342-9357, 2019 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-31040181

RESUMEN

Triple-negative breast cancers (TNBCs) lack progesterone and estrogen receptors and do not have amplified human epidermal growth factor receptor 2, the main therapeutic targets for managing breast cancer. TNBCs have an altered metabolism, including an increased Warburg effect and glutamine dependence, making the glutaminase inhibitor CB-839 therapeutically promising for this tumor type. Accordingly, CB-839 is currently in phase I/II clinical trials. However, not all TNBCs respond to CB-839 treatment, and the tumor resistance mechanism is not yet fully understood. Here we classified cell lines as CB-839-sensitive or -resistant according to their growth responses to CB-839. Compared with sensitive cells, resistant cells were less glutaminolytic and, upon CB-839 treatment, exhibited a smaller decrease in ATP content and less mitochondrial fragmentation, an indicator of poor mitochondrial health. Transcriptional analyses revealed that the expression levels of genes linked to lipid metabolism were altered between sensitive and resistant cells and between breast cancer tissues (available from The Cancer Genome Atlas project) with low versus high glutaminase (GLS) gene expression. Of note, CB-839-resistant TNBC cells had increased carnitine palmitoyltransferase 2 (CPT2) protein and CPT1 activity levels. In agreement, CB-839-resistant TNBC cells mobilized more fatty acids into mitochondria for oxidation, which responded to AMP-activated protein kinase and acetyl-CoA carboxylase signaling. Moreover, chemical inhibition of both glutaminase and CPT1 decreased cell proliferation and migration of CB-839-resistant cells compared with single inhibition of each enzyme. We propose that dual targeting of glutaminase and CPT1 activities may have therapeutic relevance for managing CB-839-resistant tumors.


Asunto(s)
Bencenoacetamidas/farmacología , Carnitina O-Palmitoiltransferasa/antagonistas & inhibidores , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Glutaminasa/antagonistas & inhibidores , Glutamina/metabolismo , Tiadiazoles/farmacología , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Femenino , Humanos , Oxidación-Reducción , Neoplasias de la Mama Triple Negativas/enzimología , Neoplasias de la Mama Triple Negativas/patología , Células Tumorales Cultivadas
18.
BMC Cancer ; 20(1): 1069, 2020 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-33167923

RESUMEN

BACKGROUND: Melanoma is the most aggressive type of skin cancer and is associated with environmental and genetic risk factors. It originates in melanocytes, the pigment-producing cells. Single nucleotide polymorphisms (SNPs) in pigmentation genes have been described in melanoma risk modulation, but knowledge in the field is still limited. METHODS: In a case-control approach (107 cases and 119 controls), we investigated the effect of four pigmentation gene SNPs (TYR rs1126809, HERC2 rs1129038, SLC24A5 rs1426654, and SLC45A2 rs16891982) on melanoma risk in individuals from southern Brazil using a multivariate logistic regression model and multifactor dimensionality reduction (MDR) analysis. RESULTS: Two SNPs were associated with an increased risk of melanoma in a dominant model: rs1129038AA and rs1426654AA [OR = 2.094 (95% CI: 1.106-3.966), P = 2.3 10- 2 and OR = 7.126 (95% CI: 1.873-27.110), P = 4.0 10- 3, respectively]. SNP rs16891982CC was associated with a lower risk to melanoma development in a log-additive model when the allele C was inherited [OR = 0.081 (95% CI: 0.008-0.782), P = 3 10- 2]. In addition, MDR analysis showed that the combination of the rs1426654AA and rs16891982GG genotypes was associated with a higher risk for melanoma (P = 3 10- 3), with a redundant effect. CONCLUSIONS: These results contribute to the current knowledge and indicate that epistatic interaction of these SNPs, with an additive or correlational effect, may be involved in modulating the risk of melanoma in individuals from a geographic region with a high incidence of the disease.


Asunto(s)
Biomarcadores de Tumor/genética , Melanoma/epidemiología , Polimorfismo de Nucleótido Simple , Neoplasias Cutáneas/epidemiología , Pigmentación de la Piel/genética , Antígenos de Neoplasias/genética , Antiportadores/genética , Brasil/epidemiología , Estudios de Casos y Controles , Femenino , Estudios de Seguimiento , Genotipo , Humanos , Incidencia , Masculino , Melanoma/genética , Melanoma/patología , Proteínas de Transporte de Membrana/genética , Persona de Mediana Edad , Monofenol Monooxigenasa/genética , Pronóstico , Factores de Riesgo , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patología , Ubiquitina-Proteína Ligasas/genética
19.
Pharm Res ; 37(10): 186, 2020 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-32888133

RESUMEN

PURPOSE: The aim of this study was to develop a nasal powder formulation of the antifibrinolytic drug, tranexamic acid (TXA), in combination with the wound-healing agent hyaluronic acid (HA) for the local treatment of epistaxis (nose bleeding). METHODS: Formulations of TXA alone and with different concentrations of HA were freeze-dried and characterised according to their physicochemical properties. Aerosol performance was assessed to ensure nasal deposition with minimal lung deposition. Nasal epithelial cells were used to assess cytotoxicity, transport across the nasal epithelium, antioxidant, wound-healing and anti-inflammatory properties of all formulations. RESULTS: Formulations containing TXA and HA were produced and found to be mostly deposited in the nasal cavity (more than 90%). Formulation of TXA + 0.3%HA showed wound reduction of 29.3% when assessed in ALI culture. At this concentration, formulations also reduced ROS production in RPMI 2650, and IL-8 production in primary nasal epithelial cells. Furthermore, for formulations containing HA, the higher viscosity may lead to larger residence time in the nasal cavity. CONCLUSIONS: Combination of TXA with HA shows promising results for the treatment of nasal epistaxis.


Asunto(s)
Antifibrinolíticos/uso terapéutico , Epistaxis/tratamiento farmacológico , Ácido Hialurónico/uso terapéutico , Ácido Tranexámico/uso terapéutico , Administración Intranasal , Aerosoles , Antifibrinolíticos/administración & dosificación , Antifibrinolíticos/química , Línea Celular , Combinación de Medicamentos , Composición de Medicamentos , Liofilización , Humanos , Ácido Hialurónico/administración & dosificación , Ácido Hialurónico/química , Interleucina-8/biosíntesis , Pulmón/metabolismo , Mucosa Nasal/efectos de los fármacos , Mucosa Nasal/metabolismo , Polvos , Especies Reactivas de Oxígeno , Ácido Tranexámico/administración & dosificación , Ácido Tranexámico/química , Cicatrización de Heridas/efectos de los fármacos
20.
BMC Gastroenterol ; 20(1): 394, 2020 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-33225890

RESUMEN

BACKGROUND: Tuberous Sclerosis Complex (TSC) is a complex and heterogeneous genetic disease that has well-established clinical diagnostic criteria. These criteria do not include gastrointestinal tumors. CASE PRESENTATION: We report a 45-year-old patient with a clinical and molecular diagnosis of TSC and a family history of cancer, presenting two rare associated findings: gastrointestinal polyposis and pancreatic neuroendocrine tumor. This patient was subjected to a genetic test with 80 cancer predisposing genes. The genetic panel revealed the presence of a large pathogenic deletion in the TSC2 gene, covering exons 2 to 16 and including the initiation codon. No changes were identified in the colorectal cancer and colorectal polyposis genes. DISCUSSION AND CONCLUSIONS: We describe a case of TSC that presented tumors of the gastro intestinal tract that are commonly unrelated to the disease. The patient described here emphasizes the importance of considering polyposis of the gastrointestinal tract and low grade neuroendocrine tumor as part of the TSC syndromic phenotype.


Asunto(s)
Angiomiolipoma , Neoplasias Renales , Esclerosis Tuberosa , Femenino , Tracto Gastrointestinal , Humanos , Persona de Mediana Edad , Mutación , Esclerosis Tuberosa/complicaciones , Esclerosis Tuberosa/genética , Proteína 2 del Complejo de la Esclerosis Tuberosa/genética
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