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1.
PLoS Biol ; 18(3): e3000470, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32150534

RESUMEN

In the spinal cord, the central canal forms through a poorly understood process termed dorsal collapse that involves attrition and remodelling of pseudostratified ventricular layer (VL) cells. Here, we use mouse and chick models to show that dorsal ventricular layer (dVL) cells adjacent to dorsal midline Nestin(+) radial glia (dmNes+RG) down-regulate apical polarity proteins, including Crumbs2 (CRB2) and delaminate in a stepwise manner; live imaging shows that as one cell delaminates, the next cell ratchets up, the dmNes+RG endfoot ratchets down, and the process repeats. We show that dmNes+RG secrete a factor that promotes loss of cell polarity and delamination. This activity is mimicked by a secreted variant of Crumbs2 (CRB2S) which is specifically expressed by dmNes+RG. In cultured MDCK cells, CRB2S associates with apical membranes and decreases cell cohesion. Analysis of Crb2F/F/Nestin-Cre+/- mice, and targeted reduction of Crb2/CRB2S in slice cultures reveal essential roles for transmembrane CRB2 (CRB2TM) and CRB2S on VL cells and dmNes+RG, respectively. We propose a model in which a CRB2S-CRB2TM interaction promotes the progressive attrition of the dVL without loss of overall VL integrity. This novel mechanism may operate more widely to promote orderly progenitor delamination.


Asunto(s)
Proteínas de la Membrana/metabolismo , Médula Espinal/citología , Médula Espinal/embriología , Animales , Adhesión Celular , Embrión de Pollo , Perros , Regulación del Desarrollo de la Expresión Génica , Células HEK293 , Humanos , Células de Riñón Canino Madin Darby , Proteínas de la Membrana/genética , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Factores de Transcripción SOXB1/genética , Factores de Transcripción SOXB1/metabolismo , Uniones Estrechas/metabolismo , Imagen de Lapso de Tiempo
2.
J Toxicol Environ Health A ; 86(6): 198-215, 2023 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-36803253

RESUMEN

The widespread use of 17α-ethinylestradiol (EE2), and other estrogenic endocrine disruptors, results in a continuous release of estrogenic compounds into aquatic environments. Xenoestrogens may interfere with the neuroendocrine system of aquatic organisms and may produce various adverse effects. The aim of the present study was to expose European sea bass larvae (Dicentrarchus labrax) to EE2 (0.5 and 50 nM) for 8 d and determine the expression levels of brain aromatase (cyp19a1b), gonadotropin-releasing hormones (gnrh1, gnrh2, gnrh3), kisspeptins (kiss1, kiss2) and estrogen receptors (esr1, esr2a, esr2b, gpera, gperb). Growth and behavior of larvae as evidenced by locomotor activity and anxiety-like behaviors were measured 8 d after EE2 treatment and a depuration period of 20 d. Exposure to 0.5 nM EE2 induced a significant increase in cyp19a1b expression levels, while upregulation of gnrh2, kiss1, and cyp19a1b expression was noted after 8 d at 50 nM EE2. Standard length at the end of the exposure phase was significantly lower in larvae exposed to 50 nM EE2 than in control; however, this effect was no longer observed after the depuration phase. The upregulation of gnrh2, kiss1, and cyp19a1b expression levels was found in conjunction with elevation in locomotor activity and anxiety-like behaviors in larvae. Behavioral alterations were still detected at the end of the depuration phase. Evidence indicates that the long-lasting effects of EE2 on behavior might impact normal development and subsequent fitness of exposed fish.


Asunto(s)
Lubina , Animales , Lubina/metabolismo , Kisspeptinas/metabolismo , Etinilestradiol/toxicidad , Etinilestradiol/metabolismo , Larva , Sistemas Neurosecretores
3.
Community Dent Health ; 40(1): 30-36, 2023 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-36696469

RESUMEN

BACKGROUND: The Black population has poorer oral health than other racial groups; however, little is known about the mechanisms that explain this difference. OBJECTIVE: To study the association between race and tooth loss and map the evidence on factors associated with tooth loss in Black older populations. METHODS: Scoping review following the PRISMA Extension for Scoping Reviews conducted according to the recommendations of the Joanna Briggs Institute. A three-step search strategy was applied, and data were collected between April and July 2021. Searches were performed in the PubMed, Lilacs, and SciELO databases. The grey literature was searched using Google Scholar (https://www.scholar.google.com/). The reference lists of included studies were used as additional sources. Studies published in English and Portuguese of the association between tooth loss and different racial groups and the factors associated with tooth loss and tooth retention in Black older adult populations were included. RESULTS: Twenty-one of 913 original articles published between 1995 and 2020 were included. Of these, 75% were research articles, 15% were reports, and 10% dissertations. Eighty per cent reported cross-sectional and 20% longitudinal data. African ancestry was associated with increased odds of tooth loss in older adult populations. Periodontal disease, female sex, and advanced age were the exposures most frequently associated with tooth loss. CONCLUSION: Race, educational level, advanced age, and oral diseases such as periodontitis are associated with increased tooth loss in Afro-descendant older populations.


Asunto(s)
Enfermedades Periodontales , Periodontitis , Pérdida de Diente , Anciano , Femenino , Humanos , Estudios Transversales , Etnicidad , Pérdida de Diente/epidemiología
4.
Med Oral Patol Oral Cir Bucal ; 28(5): e450-e456, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37622431

RESUMEN

BACKGROUND: Studies try to explain the hypothesis that maternal periodontitis may be associated with preterm birth. MATERIAL AND METHODS: This is a case-control study with 120, 40 cases (gestational age <37 weeks) and 80 controls (gestational age ≥37 weeks), that were submitted to the clinical periodontal examination and subgingival biofilm collection. Bacterial DNA of subgingival biofilm was performed and processed by qPCR. RESULTS: Periodontitis was statistically significant in the Case group (35%) when compared to the Control group (11.2%) and Gingival Bleeding Index (GBI), sites with PS ≥ 4mm and sites with CAL ≥ 5mm were statistically higher in the Case group (p < 0.05). The proportions of Pi (p = 0.026) and Fn (p = 0.041) of subgingival biofilm were higher in the Case group. A greater number of sites with PS ≥ 4mm (r = -0.202; p = 0.026) and CAL ≥ 5mm (r = -0.322; p < 0.001) were correlated to lower gestational age. CONCLUSIONS: Periodontitis, preterm delivery, and/or low birth weight may have a possible relationship based on clinical parameters and the ratio of Pi and Fn at periodontal sites.


Asunto(s)
Periodontitis , Nacimiento Prematuro , Recién Nacido , Humanos , Femenino , Lactante , Fusobacterium nucleatum , Prevotella , Estudios de Casos y Controles , Periodontitis/complicaciones
5.
Med Oral Patol Oral Cir Bucal ; 28(2): e191-e198, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36565222

RESUMEN

BACKGROUND: This study aimed to characterize the barriers faced by Brazilian dentists to deliver bad news (DBN) about oral and oropharyngeal cancer diagnoses to patients by using a questionnaire based on the guidelines of the SPIKES protocol. MATERIAL AND METHODS: This was an observational cross-sectional study. The questionnaire contained 27 questions based on the SPIKES protocol, which were answered in the SurveyMonkey platform. RESULTS: A total of 186/249 dentists answered the questionnaire. The main specialties reported were 36.02% oral medicine, 21.5% oral pathology, and 9.13% oral and maxillofacial surgery. A total of 44.6% expressed concern about the patient's emotional reactions, and 46.24% of respondents had never participated in any specific training to communicate bad news. CONCLUSIONS: The lack of training and low confidence in dealing with patients' emotional reactions dentists were considered the greatest barriers to DBNs. Moreover, most dentists who participated in the survey believe that a protocol to guide the communication of bad news would be useful for clinical practice. For those protocols to be used by dentists, training is critical for these protocols to be incorporated by professionals.


Asunto(s)
Neoplasias Orofaríngeas , Revelación de la Verdad , Humanos , Estudios Transversales , Odontólogos/psicología , Autoevaluación (Psicología) , Encuestas y Cuestionarios
6.
Hum Mol Genet ; 28(1): 105-123, 2019 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-30239717

RESUMEN

Variations in the human Crumbs homolog-1 (CRB1) gene lead to an array of retinal dystrophies including early onset of retinitis pigmentosa (RP) and Leber congenital amaurosis (LCA) in children. To investigate the physiological roles of CRB1 and CRB2 in retinal Müller glial cells (MGCs), we analysed mouse retinas lacking both proteins in MGC. The peripheral retina showed a faster progression of dystrophy than the central retina. The central retina showed retinal folds, disruptions at the outer limiting membrane, protrusion of photoreceptor nuclei into the inner and outer segment layers and ingression of photoreceptor nuclei into the photoreceptor synaptic layer. The peripheral retina showed a complete loss of the photoreceptor synapse layer, intermingling of photoreceptor nuclei within the inner nuclear layer and ectopic photoreceptor cells in the ganglion cell layer. Electroretinography showed severe attenuation of the scotopic a-wave at 1 month of age with responses below detection levels at 3 months of age. The double knockout mouse retinas mimicked a phenotype equivalent to a clinical LCA phenotype due to loss of CRB1. Localization of CRB1 and CRB2 in non-human primate (NHP) retinas was analyzed at the ultrastructural level. We found that NHP CRB1 and CRB2 proteins localized to the subapical region adjacent to adherens junctions at the outer limiting membrane in MGC and photoreceptors. Our data suggest that loss of CRB2 in MGC aggravates the CRB1-associated RP-like phenotype towards an LCA-like phenotype.


Asunto(s)
Proteínas de la Membrana/genética , Proteínas del Tejido Nervioso/genética , Retinitis Pigmentosa/genética , Animales , Proteínas Portadoras/genética , Proteínas Portadoras/fisiología , Modelos Animales de Enfermedad , Electrorretinografía , Células Ependimogliales/metabolismo , Células Ependimogliales/fisiología , Proteínas del Ojo/genética , Proteínas del Ojo/fisiología , Amaurosis Congénita de Leber/genética , Amaurosis Congénita de Leber/fisiopatología , Macaca fascicularis , Proteínas de la Membrana/fisiología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mutación , Proteínas del Tejido Nervioso/fisiología , Neuroglía/fisiología , Fenotipo , Células Fotorreceptoras/metabolismo , Células Fotorreceptoras de Vertebrados/metabolismo , Retina/metabolismo , Distrofias Retinianas/metabolismo , Retinitis Pigmentosa/metabolismo , Retinitis Pigmentosa/fisiopatología
7.
Eur J Immunol ; 50(2): 245-255, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31778214

RESUMEN

IL-23 plays an important role in the development of arthritis and the IL-23 receptor (IL-23R) is expressed on different types of T cells. However, it is not fully clear which IL-23R+ T cells are critical in driving T cell-mediated synovitis. We demonstrate, using knock-in IL-23R-GFP reporter (IL-23RGFP/+ ) mice, that CD4+ CCR6+ T cells and γδ T cells, but not CD8+ T cells, express the IL-23R(GFP). During early arthritis, IL-23R(GFP)+ CD4+ CCR6+ T cells, but not IL-23R(GFP)+ γδ T cells, were present in the inflamed joints. IL-23RGFP/+ mice were bred as homozygotes to obtain IL-23RGFP/GFP (IL-23R deficient/IL-23R-/- ) mice, which express GFP under the IL-23R promotor. Arthritis progression and joint damage were significantly milder in IL-23R-/- mice, which revealed less IL-17A+ cells in their lymphoid tissues. Surprisingly, IL-23R-/- mice had increased numbers of IL-23R(GFP)+ CD4+ CCR6+ and CCR7+ CD4+ CCR6+ T cells in their spleen compared to WT, and IL-23 suppressed CCR7 expression in vitro. However, IL-23R(GFP)+ CD4+ CCR6+ T cells were present in the synovium of IL-23R-/- mice at day 4. Finally, adoptive transfer experiments revealed that CD4+ CCR6+ T cells and not γδ T cells drive arthritis progression. These data suggest that IL-23R-dependent T cell-mediated synovitis is dependent on CD4+ CCR6+ T cells and not on γδ T cells.


Asunto(s)
Artritis/inmunología , Linfocitos T CD4-Positivos/inmunología , Inflamación/inmunología , Receptores de Antígenos de Linfocitos T gamma-delta/inmunología , Receptores CCR6/inmunología , Receptores de Interleucina/inmunología , Traslado Adoptivo/métodos , Animales , Modelos Animales de Enfermedad , Femenino , Interleucina-17/inmunología , Interleucina-23/inmunología , Tejido Linfoide/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Células Th17/inmunología
8.
J Investig Allergol Clin Immunol ; 31(6): 471-480, 2021 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-32694095

RESUMEN

BACKGROUND AND OBJECTIVES: Data on risk factors for uncontrolled asthma in preschool children are controversial. Objective: This study aims to explore the association between clinical and functional parameters and the lack of asthma control in preschool children. METHODS: Children aged 3-5 years with asthma and healthy controls were recruited. A questionnaire was used to identify potential risk factors for uncontrolled asthma, as defined by the Global INitiative for Asthma criteria. Lung function and bronchial reversibility were evaluated through impulse oscillometry and spirometry. Adjusted odds ratios were estimated based on multivariable generalized additive regression models. The discriminative ability of the models was measured by the area under the receiver operating characteristic curve (AUC). RESULTS: The study population comprised 121 children (107 with asthma and 14 healthy controls). Fifty-three patients (50%) had uncontrolled asthma. After adjustment, the variables associated with an increased risk of lack of control were as follows: "More than 3 flare-ups in the last 12 months", "Moderate to severe rhinitis", and "Relative variation in postbronchodilator FVC and FEV1". The AUC of the final models that included variation in FVC or FEV1 were 0.82 and 0.81, respectively. The R5-20, R5-20%, and AX z-score values of the healthy group were lower than those of children with asthma. CONCLUSION: In preschool children, clinical and functional parameters are associated with uncontrolled asthma. More studies are needed to confirm the usefulness of impulse oscillometry.


Asunto(s)
Asma , Asma/diagnóstico , Asma/epidemiología , Preescolar , Volumen Espiratorio Forzado , Humanos , Oportunidad Relativa , Oscilometría , Pruebas de Función Respiratoria , Espirometría
9.
Community Dent Health ; 38(3): 192-197, 2021 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-33934580

RESUMEN

AIM: To assess the prevalence of temporomandibular disorder (TMD) in adolescents and estimate possible associations with poverty. BASIC RESEARCH DESIGN: A cross-sectional study nested within a prospective birth cohort study conducted in São Luís, Maranhão, Brazil. PARTICIPANTS: 2,412 adolescents aged 18-19 years. MATERIAL AND METHODS: The presence of TMD, classified according to the Fonseca Anamnestic Index, was used as the outcome. The following explanatory variables were assessed: gender, household head, paved/asphalted street, piped water, and socioeconomic background, based on the Brazilian Association of Market Research criteria and the poverty income ratio (PIR). Logistic regression analysis was performed with the estimation of odds ratios (OR) and 95% confidence intervals. RESULTS: TMD was common (51.4%) and was associated with poverty, as it was more frequent among adolescents from social classes D-E (OR=2.60; 95% CI: 1.48-4.55) and C (OR=1.82; 95% CI: 1.12-2.99) compared to A/B, and among poor adolescents using the PIR (OR=1.50; 95% CI: 1.02-2.33). CONCLUSIONS: The prevalence of TMD in socioeconomically disadvantaged adolescents in São Luís is high, and these data allow the early identification of at-risk groups. We recommend carrying out other population-based studies, using diagnostic strategies with greater accuracy.


Asunto(s)
Trastornos de la Articulación Temporomandibular , Adolescente , Brasil/epidemiología , Estudios de Cohortes , Estudios Transversales , Humanos , Prevalencia , Estudios Prospectivos , Factores Socioeconómicos , Trastornos de la Articulación Temporomandibular/epidemiología
10.
Clin Oral Investig ; 25(10): 5855-5865, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33759000

RESUMEN

OBJECTIVES: To analyze the association between systemic inflammatory burden of cardiovascular disease (CVD) risk and periodontitis in adolescents, including mediating pathways triggered by their common risk factors. MATERIALS AND METHODS: Using a population-based sample study (n = 405) of Brazilian adolescents (17-18 years old), direct and mediation pathways triggered by "Socioeconomic Status," "Adiposity," Smoking, and "Blood Pressure" were modelled for the association between the "Systemic Circulating Inflammatory Burden of CVD Risk" (IL-1ß, IL-6, IL-8, TNF-α) and the "Initial Periodontitis" (bleeding on probing (BoP), probing depth (PD) ≥ 4 mm, clinical attachment loss (CAL) ≥ 4 mm), both as continuous latent variables, using structural equation modeling. Sensitivity analysis was performed for the outcomes "Gingivitis" (visible plaque; BoP); "Moderate Periodontitis" (PD ≥ 5 mm and CAL ≥ 5 mm) and periodontitis (CDC-AAP case definition). RESULTS: Higher "Systemic Circulating Inflammatory Burden of CVD Risk" was directly associated with higher "Initial Periodontitis" (standardized coefficient [SC] = 0.178, P value < 0.001). Lower "Socioeconomic Status" (SC = - 0.022, P value = 0.015) and Smoking (SC = 0.030, P value = 0.021) triggered the "Initial Periodontitis", mediated by "Systemic Circulating Inflammatory Burden of CVD Risk". Sensitivity analysis showed a dose-response relationship between "Systemic Circulating Inflammatory Burden of CVD Risk" and "Moderate Periodontitis" (SC = 0.323, P value = 0.021). CONCLUSIONS: "Systemic Circulating Inflammatory Burden of CVD Risk" appeared as an underlying mechanism of early periodontal breakdown in adolescents, also triggered by social vulnerability and smoking. CLINICAL RELEVANCE: The association between periodontitis and CVD in adulthood seems to establish much earlier in life than had been previously studied, giving impetus to preventive approaches focused on their common risk factors.


Asunto(s)
Placa Dental , Gingivitis , Periodontitis , Adolescente , Adulto , Humanos , Pérdida de la Inserción Periodontal , Periodontitis/epidemiología , Factor de Necrosis Tumoral alfa
11.
Eur Ann Allergy Clin Immunol ; 53(5): 214-220, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33182989

RESUMEN

SUMMARY: Introduction. The Test for Respiratory and Asthma Control in Kids (TRACK) is a tool to assess asthma control in preschool children. This study aims to validate the Portuguese from Portugal version of the TRACK questionnaire. Methods. A prospective cohort study was carried out to assess their psychometric characteristics. Caregivers of 141 children under age 5 with asthma symptoms were enrolled. Results. Internal reliability was close to 0.70 (Cronbach's α). The test-retest reliability was 0.87. TRACK scores were different between well, partially, and non-controlled asthma groups (p less than 0.001). Patients rated as having better control showed an increase in TRACK scores. Conclusions. The Portuguese version of the TRACK questionnaire is accurate and reliable for monitoring asthma control. Its use may help to overcome challenges with the management of this age group.


Asunto(s)
Asma , Comparación Transcultural , Asma/diagnóstico , Preescolar , Humanos , Portugal , Estudios Prospectivos , Reproducibilidad de los Resultados , Encuestas y Cuestionarios
12.
Int J Mol Sci ; 22(7)2021 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-33808129

RESUMEN

Mutations in the Crumbs homologue 1 (CRB1) gene cause inherited retinal dystrophies, such as early-onset retinitis pigmentosa and Leber congenital amaurosis. A Brown Norway rat strain was reported with a spontaneous insertion-deletion (indel) mutation in exon 6 of Crb1. It has been reported that these Crb1 mutant rats show vascular abnormalities associated with retinal telangiectasia and possess an early-onset retinal degenerative phenotype with outer limiting membrane breaks and focal loss of retinal lamination at 2 months of age. Here, we further characterized the morphological phenotype of new-born and adult Crb1 mutant rats in comparison with age-matched Brown Norway rats without a mutation in Crb1. A significantly decreased retinal function and visual acuity was observed in Crb1 mutant rats at 1 and 3 months of age, respectively. Moreover, in control rats, the subcellular localization of canonical CRB1 was observed at the subapical region in Müller glial cells while CRB2 was observed at the subapical region in both photoreceptors and Müller glial cells by immuno-electron microscopy. CRB1 localization was lost in the Crb1 mutant rats, whereas CRB2 was still observed. In addition, we determined the tropism of subretinal or intravitreally administered AAV5-, AAV9- or AAV6-variant ShH10Y445F vectors in new-born control and Crb1 mutant rat retinas. We showed that subretinal injection of AAV5 and AAV9 at postnatal days 5 (P5) or 8 (P8) predominantly infected the retinal pigment epithelium (RPE) and photoreceptor cells; while intravitreal injection of ShH10Y445F at P5 or P8 resulted in efficient infection of mainly Müller glial cells. Using knowledge of the subcellular localization of CRB1 and the ability of ShH10Y445F to infect Müller glial cells, canonical hCRB1 and hCRB2 AAV-mediated gene therapy were explored in new-born Crb1 mutant rats. Enhanced retinal function after gene therapy delivery in the Crb1 rat was not observed. No timely rescue of the retinal phenotype was observed using retinal function and visual acuity, suggesting the need for earlier onset of expression of recombinant hCRB proteins in Müller glial cells to rescue the severe retinal phenotype in Crb1 mutant rats.


Asunto(s)
Proteínas de Unión al Calcio/genética , Dependovirus/fisiología , Terapia Genética/métodos , Proteínas del Tejido Nervioso/genética , Distrofias Retinianas/genética , Animales , Animales Recién Nacidos , Proteínas de Unión al Calcio/metabolismo , Proteínas Portadoras/genética , Dependovirus/genética , Células Ependimogliales/metabolismo , Proteínas del Ojo/genética , Vectores Genéticos/administración & dosificación , Vectores Genéticos/farmacología , Inyecciones Intravítreas , Proteínas de la Membrana/genética , Mutación , Proteínas del Tejido Nervioso/metabolismo , Fenotipo , Ratas , Ratas Mutantes , Retina/fisiopatología , Distrofias Retinianas/etiología , Distrofias Retinianas/terapia , Epitelio Pigmentado de la Retina/metabolismo , Tropismo Viral
13.
Hum Mol Genet ; 27(18): 3137-3153, 2018 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-29893966

RESUMEN

The mammalian apical-basal determinant Crumbs homolog-1 (CRB1) plays a crucial role in retinal structure and function by the maintenance of adherens junctions between photoreceptors and Müller glial cells. Patients with mutations in the CRB1 gene develop retinal dystrophies, including early-onset retinitis pigmentosa and Leber congenital amaurosis. Previously, we showed that Crb1 knockout mice developed a slow-progressing retinal phenotype at foci in the inferior retina, although specific ablation of Crb2 in immature photoreceptors leads to an early-onset phenotype throughout the retina. Here, we conditionally disrupted one or both alleles of Crb2 in immature photoreceptors, on a genetic background lacking Crb1, and studied the retinal dystrophies thereof. Our data showed that disruption of one allele of Crb2 in immature photoreceptors caused a substantial aggravation of the Crb1 phenotype in the entire inferior retina. The photoreceptor layer showed early-onset progressive thinning limited to the inferior retina, although the superior retina maintained intact. Surprisingly, disruption of both alleles of Crb2 in immature photoreceptors further aggravated the phenotype. Throughout the retina, photoreceptor synapses were disrupted and photoreceptor nuclei intermingled with nuclei of the inner nuclear layer. In the superior retina, the ganglion cell layer appeared thicker because of ectopic nuclei of photoreceptors. In conclusion, the data suggest that CRB2 is required to maintain retinal progenitor and photoreceptor cell adhesion and prevent photoreceptor ingression into the immature inner retina. We hypothesize, from these animal models, that decreased levels of CRB2 in immature photoreceptors adjust retinitis pigmentosa because of the loss of CRB1 into Leber congenital amaurosis phenotype.


Asunto(s)
Amaurosis Congénita de Leber/genética , Proteínas de la Membrana/genética , Proteínas del Tejido Nervioso/genética , Retina/fisiopatología , Uniones Adherentes/genética , Alelos , Animales , Adhesión Celular/genética , Modelos Animales de Enfermedad , Células Ependimogliales/metabolismo , Células Ependimogliales/patología , Humanos , Amaurosis Congénita de Leber/fisiopatología , Ratones , Ratones Noqueados , Células Fotorreceptoras/metabolismo , Células Fotorreceptoras/patología , Retina/crecimiento & desarrollo , Sinapsis/genética , Sinapsis/patología
14.
BMC Med Educ ; 20(1): 449, 2020 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-33225951

RESUMEN

BACKGROUND: Electives are perceived by medical students as a valuable, highly regarded experience, allowing them to customize learning experiences and enabling them to early differentiate during medical training. The present work aims to uncover students' major determinants of satisfaction and how they interfere with their future elective choices in order to identify the best approach to implement electives in medical curricula. METHODS: A cross-sectional study was conducted through a written evaluation survey concerning the electives available in the academic year 2015-2016. Our institution provides 106 electives to students from the 2nd to the 5th year. Students' satisfaction was assessed through a validated questionnaire with eight sentences expressing opinions related to electives global satisfaction. Data from 538 inquiries from 229 students were analyzed quantitatively using regression and correlation models, and qualitatively through phenomenography. RESULTS: Quantitative analysis of the questionnaires allowed to establish both: 1) The determinants of students' satisfaction with electives, which were Agreement with teaching and learning methodologies, followed by Agreement with assessment methodologies employed, Perception of the workload demanded and Requirement for continuous work and 2) The predictors of students preferences in the following years, namely, Agreement with assessment methodologies employed, Classes attendance and Ranking of the allocated elective established in the previous year. Qualitative analysis of questionnaires revealed that students consider electives as being innovative and interesting, claiming that some, for their relevant content, could be integrated into the medical core curriculum. CONCLUSIONS: Our work raises awareness on the best practices when it comes to electives' organization to meet students' satisfaction. We can conclude that medical schools should measure students satisfaction as a tool to organize and predict future needs of electives and placements when designing and implementing this alternative student-centred curriculum or even to improve the existing practices regarding electives in medical courses.


Asunto(s)
Educación de Pregrado en Medicina , Estudiantes de Medicina , Estudios Transversales , Curriculum , Humanos , Satisfacción Personal
15.
Adv Exp Med Biol ; 1185: 159-163, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31884605

RESUMEN

Inherited retinal diseases encompass a large group of clinically and genetically heterogeneous diseases estimated to affect two million people worldwide. Among these people, approximately 80,000 are or will become blind in their first decades of life due to mutations in both alleles of the Crumbs homologue-1 (CRB1) gene. Microglia are the resident immune surveyor cells in the retina, and their roles have been heavily studied in several retinal diseases, including retinitis pigmentosa (RP), age-related macular degeneration, and diabetic retinopathy. However, very little is known about the role of microglia in CRB1-associated retinopathies. Thus, we here summarize the main findings described in the literature concerning inflammation and the role of microglia in CRB1-patients and CRB1-rodent models.


Asunto(s)
Proteínas del Ojo/genética , Proteínas de la Membrana/genética , Microglía/patología , Proteínas del Tejido Nervioso/genética , Enfermedades de la Retina/patología , Animales , Humanos , Mutación , Retinitis Pigmentosa/patología
16.
Int J Mol Sci ; 20(17)2019 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-31438467

RESUMEN

Variations in the Crumbs homolog-1 (CRB1) gene are associated with a wide variety of autosomal recessive retinal dystrophies, including early onset retinitis pigmentosa (RP) and Leber congenital amaurosis (LCA). CRB1 belongs to the Crumbs family, which in mammals includes CRB2 and CRB3. Here, we studied the specific roles of CRB2 in rod photoreceptor cells and whether ablation of CRB2 in rods exacerbates the Crb1-disease. Therefore, we assessed the morphological, retinal, and visual functional consequences of specific ablation of CRB2 from rods with or without concomitant loss of CRB1. Our data demonstrated that loss of CRB2 in mature rods resulted in RP. The retina showed gliosis and disruption of the subapical region and adherens junctions at the outer limiting membrane. Rods were lost at the peripheral and central superior retina, while gross retinal lamination was preserved. Rod function as measured by electroretinography was impaired in adult mice. Additional loss of CRB1 exacerbated the retinal phenotype leading to an early reduction of the dark-adapted rod photoreceptor a-wave and reduced contrast sensitivity from 3-months-of-age, as measured by optokinetic tracking reflex (OKT) behavior testing. The data suggest that CRB2 present in rods is required to prevent photoreceptor degeneration and vision loss.


Asunto(s)
Sensibilidad de Contraste/fisiología , Amaurosis Congénita de Leber/metabolismo , Proteínas de la Membrana/metabolismo , Retina/metabolismo , Retina/patología , Células Fotorreceptoras Retinianas Bastones/metabolismo , Animales , Sensibilidad de Contraste/genética , Modelos Animales de Enfermedad , Electrorretinografía , Inmunohistoquímica , Amaurosis Congénita de Leber/patología , Proteínas de la Membrana/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Microscopía Electrónica de Transmisión , Degeneración Retiniana/metabolismo , Degeneración Retiniana/patología , Retinitis Pigmentosa/metabolismo , Retinitis Pigmentosa/patología
17.
Med Oral Patol Oral Cir Bucal ; 24(6): e776-e781, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31655839

RESUMEN

BACKGROUND: The present study aims to estimate the possible relationship between periodontal pathogens in the oral cavity and the birth of Preterm Birth (PTB) and/or Low Birth Weight (LBW). MATERIAL AND METHODS: It's a case- control study with the subgengival biofilm samples were collected from four sites up deeper until 48 hours postpartum and were processes by Polymerase Chain Reaction (PCR) for presence the periodontal pathogens Prevotella intermedia (Pi), Fusobacterium nucleatum (Fn), Porphyromonas gingivalis (Pg), Treponema denticola (Td), Tannerella forsythia (Tf) e Aggregatibacter actinomycetemcomitans (Aa). The mothers were divided into case grup (babies weighing < 2500g and/or gestational age < 37 weeks) and control group (babies weighing ≥ 2500g and gestational age ≥ 37 weeks). Chi-square test and the measure of association obtained by Odds Ratio (OR) were used to estimate the association between the variables. RESULTS: Microbial analyses results showed no significant association between PTB and LBW with most periodontal pathogens in the oral cavity, even with association with the clinical presence of periodontitis. CONCLUSIONS: given the high presence of periodontal pathogens in the biofilm subgengival of recent mothers, it is suggested that the findings of this research serve as the basis for future studies on the pathophysiology involved in the relationship between periodontitis and PTB and/or LBW.


Asunto(s)
Nacimiento Prematuro , Aggregatibacter actinomycetemcomitans , Femenino , Humanos , Recién Nacido , Madres , Porphyromonas gingivalis , Embarazo , Prevotella intermedia , Treponema denticola
18.
Med Oral Patol Oral Cir Bucal ; 24(2): e211-e216, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30818314

RESUMEN

BACKGROUND: The purpose of this study was to assess the association between chronic kidney diseases (CKD) and dental caries. MATERIAL AND METHODS: 107 patients with CKD and 107 with no systemic alteration were randomly included. DMFT (decayed, missing, and filled teeth), plaque index, colony-forming units (CFU) of Streptococcus mutans and salivary composition (IgA total, IgA anti- Streptococcus mutans, calcium and urea) were evaluated. McNemar and Wilcoxon tests were used to compare test and control groups. Spearman test was used to correlate time of hemodialysis and variables studied. Associations between variables were evaluated by logistic regression analysis. RESULTS: The number of filled teeth, the amount of IgA anti-Streptococcus mutans, salivary urea, education level, monthly income and the amount of CFU of Streptococcus mutans were statistically different between groups. There was a positive correlation between the duration of hemodialysis (Hd) and the amount of IgA anti-Streptococcus mutans, urea in saliva, and the number of CFU of Streptococcus mutans. In the adjusted model, a higher incidence of CFU mutans streptococci, elevated salivary urea, smaller number of filled teeth, lower DMFT, and less calcium salivary were associated with CKD. CONCLUSIONS: Programs to prevent and treat oral problems and regular follow-up at the beginning of dialysis are necessary to increase patients' awareness of their condition.


Asunto(s)
Caries Dental/complicaciones , Caries Dental/microbiología , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/microbiología , Streptococcus mutans/patogenicidad , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Antibacterianos , Calcio/análisis , Estudios de Casos y Controles , Recuento de Colonia Microbiana , Estudios Transversales , Índice de Placa Dental , Femenino , Humanos , Inmunoglobulina A , Modelos Logísticos , Masculino , Persona de Mediana Edad , Salud Bucal , Análisis de Regresión , Diálisis Renal/efectos adversos , Saliva/química , Saliva/inmunología , Factores Socioeconómicos , Streptococcus mutans/inmunología , Urea/análisis , Adulto Joven
19.
Trop Anim Health Prod ; 51(1): 43-47, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29987648

RESUMEN

Although some studies in sheep have indicated leptospire colonization of the genital tract, further studies are needed to clarify the role of genital carriers in this species. Thus, this study aimed to evaluate the colonization of pathogenic leptospires in the genital and urinary tract of slaughtered sheep. Fifty-seven adult, female woolless sheep destined for slaughter were used. Renal (n = 57), bladder (n = 57), ovary (n = 34), uterine tube (n = 44), and uterus (n = 33) samples were collected for molecular detection of Leptospira sp. DNA, and blood samples (n = 57) for serological testing. The molecular testing was performed using polymerase chain reaction (PCR), and the serological testing was performed using microscopic serum agglutination test (MAT). Samples with amplifying DNA were subjected to genetic sequencing. In total, leptospiral DNA was found in the tissues of 44 (77.2%) sheep, whereas only nine animals were positive on both PCR and MAT; there was slight agreement between PCR and MAT techniques (k = 0.0268; p = 0.684). In 61 (54.9%) genital tract and in five (4.4%) urinary tract samples, the leptospiral DNA was detected, with significant difference (p < 0.001). The genes of one sample from the uterine tube and another from the bladder were sequenced and demonstrated 99% similarity to Leptospira interrogans. Anti-Leptospira antibodies were detected in 11 (19.3%) of the tested animals. The results reinforce the importance of the genital tract as an extra-renal site of colonization, suggesting the possibility of venereal transmission in sheep.


Asunto(s)
Genitales/microbiología , Leptospira interrogans/aislamiento & purificación , Leptospirosis/veterinaria , Ovinos/microbiología , Sistema Urinario/microbiología , Pruebas de Aglutinación , Animales , Brasil/epidemiología , Femenino , Riñón/microbiología , Leptospira/inmunología , Leptospira interrogans/genética , Leptospirosis/epidemiología , Reacción en Cadena de la Polimerasa/veterinaria , Ovinos/genética , Útero/microbiología
20.
Arch Virol ; 163(11): 3203-3206, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30097743

RESUMEN

A novel polyomavirus (PyVs) comprising 5,422 bp was identified by high-throughput sequencing (HTS) in pooled organs of nutria (Myocastor coypus). The new genome displays the archetypal organization of PyVs, which includes open reading frames for the regulatory proteins small T antigen (sTAg) and large T antigen (LTAg), as well as for the capsid proteins VP1, VP2 and VP3. Based on the International Committee on Taxonomy of Viruses (ICTV) Polyomaviridae Study Group criteria, this genome comprises a new PyVs species for the Alphapolyomavirus genus and is putatively named "Myocastor coypus Polyomavirus 1" . The complete genome sequence of this Myocastor coypus Polyomavirus 1 (McPyV1) isolate is publically available under the GenBank accession no. MH182627.


Asunto(s)
Infecciones por Polyomavirus/veterinaria , Poliomavirus/aislamiento & purificación , Enfermedades de los Roedores/virología , Roedores/virología , Animales , Antígenos Virales de Tumores/genética , Proteínas de la Cápside/genética , Genoma Viral , Secuenciación de Nucleótidos de Alto Rendimiento , Sistemas de Lectura Abierta , Filogenia , Poliomavirus/clasificación , Poliomavirus/genética , Infecciones por Polyomavirus/virología , Ratas
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