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1.
Mol Psychiatry ; 2024 Mar 07.
Article in English | MEDLINE | ID: mdl-38454085

ABSTRACT

Adult cytogenesis, the continuous generation of newly-born neurons (neurogenesis) and glial cells (gliogenesis) throughout life, is highly impaired in several neuropsychiatric disorders, such as Major Depressive Disorder (MDD), impacting negatively on cognitive and emotional domains. Despite playing a critical role in brain homeostasis, the importance of gliogenesis has been overlooked, both in healthy and diseased states. To examine the role of newly formed glia, we transplanted Glial Restricted Precursors (GRPs) into the adult hippocampal dentate gyrus (DG), or injected their secreted factors (secretome), into a previously validated transgenic GFAP-tk rat line, in which cytogenesis is transiently compromised. We explored the long-term effects of both treatments on physiological and behavioral outcomes. Grafted GRPs reversed anxiety-like deficits and demonstrated an antidepressant-like effect, while the secretome promoted recovery of only anxiety-like behavior. Furthermore, GRPs elicited a recovery of neurogenic and gliogenic levels in the ventral DG, highlighting the unique involvement of these cells in the regulation of brain cytogenesis. Both GRPs and their secretome induced significant alterations in the DG proteome, directly influencing proteins and pathways related to cytogenesis, regulation of neural plasticity and neuronal development. With this work, we demonstrate a valuable and specific contribution of glial progenitors to normalizing gliogenic levels, rescuing neurogenesis and, importantly, promoting recovery of emotional deficits characteristic of disorders such as MDD.

2.
Res Sq ; 2023 Mar 31.
Article in English | MEDLINE | ID: mdl-37034743

ABSTRACT

Adult cytogenesis, the continuous generation of newly-born neurons (neurogenesis) and glial cells (gliogenesis) throughout life, is highly impaired in several neuropsychiatric disorders, such as Major Depressive Disorder (MDD), impacting negatively on cognitive and emotional domains. Despite playing a critical role in brain homeostasis, the importance of gliogenesis has been overlooked, both in healthy and diseased states. To examine the role of newly formed glia, we transplanted Glial Restricted Precursors (GRPs) into the adult hippocampal dentate gyrus (DG), or injected their secreted factors (secretome), into a previously validated transgenic GFAP-tk rat line, in which cytogenesis is transiently compromised. We explored the long-term effects of both treatments on physiological and behavioral outcomes. Grafted GRPs reversed anxiety-like and depressive-like deficits, while the secretome promoted recovery of only anxiety-like behavior. Furthermore, GRPs elicited a recovery of neurogenic and gliogenic levels in the ventral DG, highlighting the unique involvement of these cells in the regulation of brain cytogenesis. Both GRPs and their secretome induced significant alterations in the DG proteome, directly influencing proteins and pathways related to cytogenesis, regulation of neural plasticity and neuronal development. With this work, we demonstrate a valuable and specific contribution of glial progenitors to normalizing gliogenic levels, rescueing neurogenesis and, importantly, promoting recovery of emotional deficits characteristic of disorders such as MDD.

3.
Cells ; 12(3)2023 01 20.
Article in English | MEDLINE | ID: mdl-36766724

ABSTRACT

Major depressive disorder (MDD) is a multidimensional psychiatric disorder that is estimated to affect around 350 million people worldwide. Generating valid and effective animal models of depression is critical and has been challenging for neuroscience researchers. For preclinical studies, models based on stress exposure, such as unpredictable chronic mild stress (uCMS), are amongst the most reliable and used, despite presenting concerns related to the standardization of protocols and time consumption for operators. To overcome these issues, we developed an automated system to expose rodents to a standard uCMS protocol. Here, we compared manual (uCMS) and automated (auCMS) stress-exposure protocols. The data shows that the impact of the uCMS exposure by both methods was similar in terms of behavioral (cognition, mood, and anxiety) and physiological (cell proliferation and endocrine variations) measurements. Given the advantages of time and standardization, this automated method represents a step forward in this field of preclinical research.


Subject(s)
Depressive Disorder, Major , Rats , Animals , Anxiety , Cognition
4.
Saúde Soc ; 32(supl.1): e220918pt, 2023. tab, graf
Article in English, Portuguese | LILACS | ID: biblio-1530436

ABSTRACT

Resumo Este artigo apresenta os resultados da revisão narrativa sobre as fake news ocorridas durante o período mais crítico da pandemia de covid-19. Foi realizada uma busca por palavras nas bases de dados da BVSMS, BVSalud e Scielo, utilizando-se a expressão fake news AND covid-19, notícia falsa AND covid-19 e desinformación AND Covid-19, por ser expressões que atendiam aos dois idiomas selecionados para a revisão: português e espanhol. O critério de inclusão privilegiou os artigos que utilizaram a web como fonte das pesquisas, publicados entre 2020 e 2022. Foram analisados 24 artigos, sendo 14 escritos em língua portuguesa e 10 em espanhol. O ano de 2022 concentrou o maior número de publicações (n=11), e concluiu-se que as redes sociais são os veículos de maior disseminação desse tipo de desinformação. A disseminação das fake news durante o segundo ano da pandemia de covid-19 foi tão preocupante quanto a própria doença, mas a literatura ainda não explorou suficiente o fenômeno que ainda acompanha a pandemia ainda não finalizada. A maioria dos textos analisados aconselham a utilização da estratégia disseminadora de notícias para divulgar informações úteis sobre saúde, concluindo-se que os estudos analisados demonstraram que as notícias falsas estavam incompletas ou enganosas, mas a maioria foi não intencional.


Abstract This article presents the results of the narrative review on fake news that occurred during the most critical period of the COVID-19 pandemic. A word search was carried out in the BVSMS, BVSalud, and Scielo databases, using the expression fake news AND COVID-19, notícia falsa AND COVID-19, and desinformación AND COVID-19, since these expressions addressed the two languages selected for the review: Portuguese and Spanish. The inclusion criterion favored articles that used the web as a source of research, published between 2020 and 2022. A total of 24 articles were analyzed, 14 written in Portuguese and 10 in Spanish. The year 2022 concentrated the largest number of publications (n=11), and we concluded that social networks are the vehicles for the greatest dissemination of this type of information. The spread of fake news during the second year of the COVID-19 pandemic was as worrying as the disease itself, but the literature has not explored sufficiently the phenomenon that still follows the pandemic still underway. Most of the analyzed texts advised to the use of the news dissemination strategy to disseminate useful information about health, concluding that the analyzed studies demonstrated that the false news were incomplete or misleading, but most were unintentional.


Subject(s)
Health Communication , Social Media , Disinformation
5.
Sensors (Basel) ; 22(24)2022 Dec 12.
Article in English | MEDLINE | ID: mdl-36560107

ABSTRACT

This paper presents a generic framework for fault prognosis using autoencoder-based deep learning methods. The proposed approach relies upon a semi-supervised extrapolation of autoencoder reconstruction errors, which can deal with the unbalanced proportion between faulty and non-faulty data in an industrial context to improve systems' safety and reliability. In contrast to supervised methods, the approach requires less manual data labeling and can find previously unknown patterns in data. The technique focuses on detecting and isolating possible measurement divergences and tracking their growth to signalize a fault's occurrence while individually evaluating each monitored variable to provide fault detection and prognosis. Additionally, the paper also provides an appropriate set of metrics to measure the accuracy of the models, which is a common disadvantage of unsupervised methods due to the lack of predefined answers during training. Computational results using the Commercial Modular Aero Propulsion System Simulation (CMAPSS) monitoring data show the effectiveness of the proposed framework.


Subject(s)
Benchmarking , Neural Networks, Computer , Reproducibility of Results , Prognosis , Computer Simulation
6.
Cell Prolif ; 55(2): e13165, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34970787

ABSTRACT

OBJECTIVES: The action of stress hormones, mainly glucocorticoids, starts and coordinates the systemic response to stressful events. The HPA axis activity is predicated on information processing and modulation by upstream centres, such as the hippocampus where adult-born neurons (hABN) have been reported to be an important component in the processing and integration of new information. Still, it remains unclear whether and how hABN regulates HPA axis activity and CORT production, particularly when considering sex differences. MATERIALS AND METHODS: Using both sexes of a transgenic rat model of cytogenesis ablation (GFAP-Tk rat model), we examined the endocrinological and behavioural effects of disrupting the generation of new astrocytes and neurons within the hippocampal dentate gyrus (DG). RESULTS: Our results show that GFAP-Tk male rats present a heightened acute stress response. In contrast, GFAP-Tk female rats have increased corticosterone secretion at nadir, a heightened, yet delayed, response to an acute stress stimulus, accompanied by neuronal hypertrophy in the basal lateral amygdala and increased expression of the glucocorticoid receptors in the ventral DG. CONCLUSIONS: Our results reveal that hABN regulation of the HPA axis response is sex-differentiated.


Subject(s)
Hypothalamo-Hypophyseal System/metabolism , Pituitary-Adrenal System/diagnostic imaging , Pituitary-Adrenal System/metabolism , Sex Differentiation/drug effects , Animals , Brain/drug effects , Brain/metabolism , Corticosterone/metabolism , Corticosterone/pharmacology , Female , Hippocampus/drug effects , Hippocampus/metabolism , Hypothalamo-Hypophyseal System/drug effects , Male , Neurons/metabolism , Pituitary-Adrenal System/drug effects , Rats, Transgenic , Receptors, Glucocorticoid/metabolism , Sex Differentiation/physiology
7.
Elife ; 102021 12 03.
Article in English | MEDLINE | ID: mdl-34859784

ABSTRACT

The transcription factor activating protein two gamma (AP2γ) is an important regulator of neurogenesis both during embryonic development as well as in the postnatal brain, but its role for neurophysiology and behavior at distinct postnatal periods is still unclear. In this work, we explored the neurogenic, behavioral, and functional impact of a constitutive and heterozygous AP2γ deletion in mice from early postnatal development until adulthood. AP2γ deficiency promotes downregulation of hippocampal glutamatergic neurogenesis, altering the ontogeny of emotional and memory behaviors associated with hippocampus formation. The impairments induced by AP2γ constitutive deletion since early development leads to an anxious-like phenotype and memory impairments as early as the juvenile phase. These behavioral impairments either persist from the juvenile phase to adulthood or emerge in adult mice with deficits in behavioral flexibility and object location recognition. Collectively, we observed a progressive and cumulative impact of constitutive AP2γ deficiency on the hippocampal glutamatergic neurogenic process, as well as alterations on limbic-cortical connectivity, together with functional behavioral impairments. The results herein presented demonstrate the modulatory role exerted by the AP2γ transcription factor and the relevance of hippocampal neurogenesis in the development of emotional states and memory processes.


Subject(s)
Anxiety/genetics , Memory Disorders/genetics , Transcription Factor AP-2/deficiency , Age Factors , Animals , Male , Mice
8.
Mol Psychiatry ; 26(12): 7154-7166, 2021 12.
Article in English | MEDLINE | ID: mdl-34521994

ABSTRACT

Impaired ability to generate new cells in the adult brain has been linked to deficits in multiple emotional and cognitive behavioral domains. However, the mechanisms by which abrogation of adult neural stem cells (NSCs) impacts on brain function remains controversial. We used a transgenic rat line, the GFAP-Tk, to selectively eliminate NSCs and assess repercussions on different behavioral domains. To assess the functional importance of newborn cells in specific developmental stages, two parallel experimental timeframes were adopted: a short- and a long-term timeline, 1 and 4 weeks after the abrogation protocol, respectively. We conducted in vivo electrophysiology to assess the effects of cytogenesis abrogation on the functional properties of the hippocampus and prefrontal cortex, and on their intercommunication. Adult brain cytogenesis abrogation promoted a time-specific installation of behavioral deficits. While the lack of newborn immature hippocampal neuronal and glial cells elicited a behavioral phenotype restricted to hyperanxiety and cognitive rigidity, specific abrogation of mature new neuronal and glial cells promoted the long-term manifestation of a more complex behavioral profile encompassing alterations in anxiety and hedonic behaviors, along with deficits in multiple cognitive modalities. More so, abrogation of 4 to 7-week-old cells resulted in impaired electrophysiological synchrony of neural theta oscillations between the dorsal hippocampus and the medial prefrontal cortex, which are likely to contribute to the described long-term cognitive alterations. Hence, this work provides insight on how newborn neurons and astrocytes display different functional roles throughout different maturation stages, and establishes common ground to reconcile contrasting results that have marked this field.


Subject(s)
Cognitive Dysfunction , Hippocampus , Neural Stem Cells , Prefrontal Cortex , Animals , Cognition/physiology , Cognitive Dysfunction/pathology , Emotions , Hippocampus/pathology , Neural Stem Cells/pathology , Neurons/pathology , Prefrontal Cortex/pathology , Rats , Rats, Transgenic
9.
Rom J Intern Med ; 58(1): 13-19, 2020 Mar 01.
Article in English | MEDLINE | ID: mdl-31446430

ABSTRACT

INTRODUCTION: Diabetic neuropathy (DN) is one of the most devastating complications of diabetes mellitus; however, in contrast to other countries, there are no scientific studies in Portugal evaluating the impact of demographic and clinical characteristics of this pathological entity. The aim of this study was to evaluate the impact of gender, metabolic control, age of diabetic patients, as well as time of disease progression, the appearance of complaints related to neuropathic pain. MATERIAL AND METHODS: A multicentre study with a non-probabilistic, convenience sample of 359 patients was performed employing the quantitative method, using the Statistical Package for Social Science 24 software. The p-value of p < 0.05 was defined to consider a result statistically significant. The Spearman correlation coefficient (r) was determined to determine the relationship between categorical variables. RESULTS: There was no statistically significant difference in the prevalence of DN between genders (p = 0.633 and r = 0.025). There was a statistically significant relationship between the value of HbA1c and DN, with p = 0.010 and r = 0.136. There is a relationship between age and complaints of neuropathic pain, with p = 0.034 and r = 0.112. The variable, time of disease progression, is also correlated with the appearance of complaints of neuropathic pain with p = 0.020 and r = 0.112. CONCLUSION: The prevalence of neuropathic pain in subjects with diabetes is not negligible and is associated with modifiable risk factors that can be identified, possibly modified and prevented. The correct approach for these patients, which involves screening and early treatment, is decisive improving functionality and quality of life.


Subject(s)
Diabetic Neuropathies/diagnosis , Age of Onset , Aged , Diabetic Neuropathies/blood , Diabetic Neuropathies/therapy , Disease Progression , Female , Glycated Hemoglobin/metabolism , Humans , Male , Middle Aged , Quality of Life , Risk Factors , Sex Factors , Time Factors
10.
Braz Oral Res ; 292015.
Article in English | MEDLINE | ID: mdl-25627883

ABSTRACT

This study investigated the presence of the Treponema species in longstanding endodontic retreatment-resistant lesions of teeth with apical periodontitis, the association of this species with clinical/radiographic features, and the association among the different target species. Microbial samples of apical lesions were collected from twenty-five adult patients referred to endodontic surgery after unsuccessful root canal retreatment. Nested-PCR and conventional PCR were used for Treponema detection. Twenty-three periradicular tissue samples showed detectable levels of bacterial DNA. Treponema species were detected in 28% (7/25) of the cases. The most frequently detected species were T. socranskii (6/25), followed by T. maltophilum (3/25), T. amylovorum (3/25), T. lecithinolyticum (3/25), T. denticola (3/25), T. pectinovorum (2/25) and T. medium (2/25). T. vicentii was not detected in any sample. Positive statistical association was found between T. socranskii and T. denticola, and between T. maltophilum and T. lecithinolyticum . No association was detected between the presence of any target microorganism and the clinical or radiographic features. Treponema spp. are present, in a low percentage, in longstanding apical lesions from teeth with endodontic retreatment failure.


Subject(s)
Periapical Periodontitis/microbiology , Periapical Periodontitis/therapy , Periapical Tissue/microbiology , Treponema/isolation & purification , Treponemal Infections/microbiology , Adolescent , Adult , Aged , Chi-Square Distribution , DNA, Bacterial/analysis , Female , Humans , Male , Middle Aged , Periapical Periodontitis/diagnostic imaging , Periapical Periodontitis/pathology , Periapical Tissue/diagnostic imaging , Periapical Tissue/pathology , Polymerase Chain Reaction , Radiography , Retreatment , Root Canal Therapy , Treatment Failure , Treponemal Infections/diagnostic imaging , Young Adult
11.
Braz. oral res. (Online) ; 29(1): 1-1, 2015. tab
Article in English | LILACS | ID: lil-777182

ABSTRACT

This study investigated the presence of the Treponema species in longstanding endodontic retreatment-resistant lesions of teeth with apical periodontitis, the association of this species with clinical/radiographic features, and the association among the different target species. Microbial samples of apical lesions were collected from twenty-five adult patients referred to endodontic surgery after unsuccessful root canal retreatment. Nested-PCR and conventional PCR were used for Treponema detection. Twenty-three periradicular tissue samples showed detectable levels of bacterial DNA. Treponema species were detected in 28% (7/25) of the cases. The most frequently detected species were T. socranskii (6/25), followed by T. maltophilum (3/25), T. amylovorum (3/25), T. lecithinolyticum(3/25), T. denticola (3/25), T. pectinovorum (2/25) and T. medium(2/25). T. vicentii was not detected in any sample. Positive statistical association was found between T. socranskiiand T. denticola,and between T. maltophilumand T. lecithinolyticum. No association was detected between the presence of any target microorganism and the clinical or radiographic features. Treponemaspp.are present, in a low percentage, in longstanding apical lesions from teeth with endodontic retreatment failure.


Subject(s)
Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , Periapical Periodontitis/microbiology , Periapical Periodontitis/therapy , Periapical Tissue/microbiology , Treponema/isolation & purification , Treponemal Infections/microbiology , Chi-Square Distribution , DNA, Bacterial/analysis , Polymerase Chain Reaction , Periapical Periodontitis/pathology , Periapical Periodontitis , Periapical Tissue/pathology , Periapical Tissue , Retreatment , Root Canal Therapy , Treatment Failure , Treponemal Infections
12.
J Appl Oral Sci ; 22(1): 61-7, 2014.
Article in English | MEDLINE | ID: mdl-24626250

ABSTRACT

UNLABELLED: A calcium aluminate-based endodontic material, EndoBinder, has been developed in order to reduce MTA negative characteristics, preserving its biological properties and clinical applications. OBJECTIVES: The aim of this study was to evaluate the cytotoxicity, antimicrobial activity, pH, solubility and water sorption of EndoBinder and to compare them with those of white MTA (WMTA). MATERIAL AND METHODS: Cytotoxicity was assessed through a multiparametric analysis employing 3T3 cells. Antimicrobial activity against Enterococcus faecalis (ATCC 29212), Staphylococcus aureus. (ATCC 25923) and Candida albicans (ATCC 10556) was determined by the agar diffusion method. pH was measured at periods of 3, 24, 72 and 168 hours. Solubility and water sorption evaluation were performed following ISO requirements. Data were statistically analyzed by ANOVA and Tukey`s test with a significance level of 5%. RESULTS: EndoBinder and WMTA were non-cytotoxic in all tested periods and with the different cell viability parameters. There was no statistical differences between both materials (P>.05). All tested materials were inhibitory by direct contact against all microbial strains tested. EndoBinder and WMTA presented alkaline pH in all tested times with higher values of pH for WMTA (P<.05). Both materials showed values complying with the solubility minimum requirements. However, EndoBinder showed lower solubility than WMTA (P<.05). No statistical differences were observed regarding water sorption (P>.05). CONCLUSION: Under these experimental conditions, we concluded that the calcium aluminate-based endodontic material EndoBinder demonstrated suitable biological and physicochemical properties, so it can be suggested as a material of choice in root resorption, perforations and root-end filling.


Subject(s)
Aluminum Compounds/toxicity , Calcium Compounds/toxicity , Oxides/toxicity , Root Canal Filling Materials/toxicity , Silicates/toxicity , 3T3 Cells , Aluminum Compounds/chemistry , Animals , Calcium Compounds/chemistry , Candida albicans/drug effects , Candida albicans/isolation & purification , Drug Combinations , Enterococcus faecalis/drug effects , Enterococcus faecalis/isolation & purification , Hydrogen-Ion Concentration , Materials Testing , Mice , Oxides/chemistry , Reproducibility of Results , Root Canal Filling Materials/chemistry , Silicates/chemistry , Solubility , Staphylococcus aureus/drug effects , Staphylococcus aureus/isolation & purification , Time Factors , Water/chemistry
13.
J. appl. oral sci ; 22(1): 61-67, Jan-Feb/2014. tab, graf
Article in English | LILACS, BBO - Dentistry | ID: lil-699911

ABSTRACT

A calcium aluminate-based endodontic material, EndoBinder, has been developed in order to reduce MTA negative characteristics, preserving its biological properties and clinical applications. Objectives: The aim of this study was to evaluate the cytotoxicity, antimicrobial activity, pH, solubility and water sorption of EndoBinder and to compare them with those of white MTA (WMTA). Material and Methods: Cytotoxicity was assessed through a multiparametric analysis employing 3T3 cells. Antimicrobial activity against Enterococcus faecalis (ATCC 29212), Staphylococcus aureus. (ATCC 25923) and Candida albicans (ATCC 10556) was determined by the agar diffusion method. pH was measured at periods of 3, 24, 72 and 168 hours. Solubility and water sorption evaluation were performed following ISO requirements. Data were statistically analyzed by ANOVA and Tukey`s test with a significance level of 5%. Results: EndoBinder and WMTA were non-cytotoxic in all tested periods and with the different cell viability parameters. There was no statistical differences between both materials (P>.05). All tested materials were inhibitory by direct contact against all microbial strains tested. EndoBinder and WMTA presented alkaline pH in all tested times with higher values of pH for WMTA (P<.05). Both materials showed values complying with the solubility minimum requirements. However, EndoBinder showed lower solubility than WMTA (P<.05). No statistical differences were observed regarding water sorption (P>.05). Conclusion: Under these experimental conditions, we concluded that the calcium aluminate-based endodontic material EndoBinder demonstrated suitable biological and physicochemical properties, so it can be suggested as a material of choice in root resorption, perforations and root-end filling. .


Subject(s)
Animals , Mice , Aluminum Compounds/toxicity , Calcium Compounds/toxicity , Oxides/toxicity , Root Canal Filling Materials/toxicity , Silicates/toxicity , Aluminum Compounds/chemistry , Calcium Compounds/chemistry , Candida albicans/drug effects , Candida albicans/isolation & purification , Drug Combinations , Enterococcus faecalis/drug effects , Enterococcus faecalis/isolation & purification , Hydrogen-Ion Concentration , Materials Testing , Oxides/chemistry , Reproducibility of Results , Root Canal Filling Materials/chemistry , Silicates/chemistry , Solubility , Staphylococcus aureus/drug effects , Staphylococcus aureus/isolation & purification , Time Factors , Water/chemistry
14.
Indian J Dent Res ; 25(6): 698-701, 2014.
Article in English | MEDLINE | ID: mdl-25728099

ABSTRACT

INTRODUCTION: The aim of this study was to evaluate the quality and bond strength of three root filling techniques (lateral compaction, continuous wave of condensation and Tagger's Hybrid technique [THT]) using micro-computed tomography (CT) images and push-out tests, respectively. MATERIALS AND METHODS: Thirty mandibular incisors were prepared using the same protocol and randomly divided into three groups (n=10): Lateral condensation technique (LCT), continuous wave of condensation technique (CWCT), and THT. All specimens were filled with Gutta-percha (GP) cones and AH Plus sealer. Five specimens of each group were randomly chosen for micro-CT analysis and all of them were sectioned into 1 mm slices and subjected to push-out tests. RESULTS: Micro-CT analysis revealed less empty spaces when GP was heated within the root canals in CWCT and THT when compared to LCT. Push-out tests showed that LCT and THT had a significantly higher displacement resistance (P<0.05) when compared to the CWCT. Bond strength was lower in apical and middle thirds than in the coronal thirds. CONCLUSIONS: It can be concluded that LCT and THT were associated with higher bond strengths to intraradicular dentine than CWCT. However, LCT was associated with more empty voids than the other techniques.


Subject(s)
Dental Bonding , Dental Pulp Cavity/diagnostic imaging , Root Canal Filling Materials/chemistry , Root Canal Obturation/methods , X-Ray Microtomography , Dental Stress Analysis , Epoxy Resins/chemistry , Gutta-Percha/chemistry , Humans , In Vitro Techniques , Incisor/diagnostic imaging , Materials Testing
15.
Microsc Res Tech ; 76(12): 1292-6, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24123537

ABSTRACT

The aim of this study was to evaluate the biocompatibility in rat subcutaneous connective tissue of a new zinc oxide endodontic sealer (Endomethasone N) compared to those provided by Endofill and Sealer 26. Polyethylene tubes containing the test materials were implanted into dorsal subcutaneous connective tissue of Wistar albino rats. After 7 and 42 days, the implants with the surrounding tissue were collected, fixed, and processed for histologic evaluation. Sections were evaluated for the presence of inflammatory cells (poly or monomorfonuclear), blood vessels, necrosis area, and thickness of fibrous capsule. Comparisons between groups and time-periods were performed with Kruskal-Wallis and Mann-Whitney U non-parametric tests for 5% significance level. No differences in the biocompatibility patterns among the materials for the 2 experimental periods were observed. Independently of the sealer, the tissue behavior showed a tendency to decrease the irritation effect over time. It can be concluded that all sealers are irritant, but its toxicity decreased with time. Endomethásone N showed biocompatible characteristics comparable with those provided by Endofill and Sealer 26.


Subject(s)
Connective Tissue/drug effects , Dexamethasone/pharmacology , Formaldehyde/pharmacology , Hydrocortisone/pharmacology , Subcutaneous Tissue/drug effects , Thymol/analogs & derivatives , Zinc Oxide-Eugenol Cement/pharmacology , Animals , Biocompatible Materials/pharmacology , Bismuth/pharmacology , Calcium Hydroxide/pharmacology , Drug Combinations , Inflammation/chemically induced , Male , Materials Testing , Rats , Rats, Wistar , Root Canal Filling Materials/pharmacology , Thymol/pharmacology
16.
Gen Dent ; 61(2): 45-9, 2013.
Article in English | MEDLINE | ID: mdl-23454321

ABSTRACT

This study used differential root weakening to evaluate the fracture resistance of bovine teeth restored using glass fiber posts (with or without accessory glass fiber posts). Fifty bovine mandibular incisors were sectioned 14 mm from the apex, fixed in acrylic resin blocks, and divided into 5 groups: healthy roots with a glass fiber post (Group 1), partially weakened teeth with a glass fiber post (Group 2), partially weakened teeth with a glass fiber post and 2 accessory glass fiber posts (Group 3), extensively weakened teeth with a glass fiber post (Group 4), and extensively weakened teeth with a glass fiber post and 5 accessory glass fiber posts (Group 5). Posts were luted with resin cement, cores were prepared using composite resin, and metallic crowns were cemented. The specimens were stored in distilled water at 37°C for more than 72 hours until the fracture resistance test. Specimens were loaded at 135 degrees relative to the long axis of the tooth at a crosshead speed of 0.5 mm/minute in a universal testing machine. All groups predominantly exhibited favorable failure patterns and there were no statistically significant differences between groups (two-way ANOVA, α = 0.05).


Subject(s)
Dental Stress Analysis , Glass , Post and Core Technique , Tooth Fractures , Tooth Root , Analysis of Variance , Animals , Cattle , Dental Materials , Resin Cements
17.
J Endod ; 39(2): 274-7, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23321245

ABSTRACT

INTRODUCTION: The aim of the study was to evaluate the cytotoxicity, radiopacity, pH, and flow of a calcium silicate-based and an epoxy resin-based endodontic sealer, MTA Fillapex (Angelus, Londrina, PR, Brazil) and AH Plus (Dentsply, Konstanz, Germany), respectively. METHODS: Cytotoxicity, radiopacity, and flow evaluation were performed following ISO requirements. The pH level was measured at periods of 3, 24, 72, and 168 hours. Cytotoxicity was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay to check the Balb/c 3T3 cells viability at 1- to 4-week periods. Data were statistically analyzed by analysis of variance and the Tukey test with a significance level of 5%. RESULTS: In all tested periods, MTA Fillapex was more cytotoxic than AH Plus (P < .05). Although AH Plus presented higher radiopacity than MTA Fillapex (P < .05), both sealers showed minimum required values. MTA Fillapex presented alkaline pH in all experimental times, whereas AH Plus cement showed a slightly neutral pH and a flow significantly lower than that of MTA Fillapex (P < .05). CONCLUSIONS: Although MTA Fillapex was more cytotoxic than AH Plus, it showed suitable physicochemical properties for an endodontic sealer.


Subject(s)
Aluminum Compounds/toxicity , Calcium Compounds/toxicity , Epoxy Resins/toxicity , Oxides/toxicity , Root Canal Filling Materials/toxicity , Silicates/toxicity , 3T3 Cells , Aluminum Compounds/chemistry , Animals , Calcium Compounds/chemistry , Cell Survival/drug effects , Chemical Phenomena , Coloring Agents , Contrast Media/chemistry , Drug Combinations , Epoxy Resins/chemistry , Fibroblasts/drug effects , Hydrogen-Ion Concentration , Materials Testing , Mice , Mice, Inbred BALB C , Oxides/chemistry , Rheology , Root Canal Filling Materials/chemistry , Silicates/chemistry , Tetrazolium Salts , Thiazoles , Time Factors
18.
Rev. enferm. UFSM ; 1(1): 51-60, jan.-abr. 2011.
Article in Portuguese | BDENF - Nursing | ID: biblio-1033984

ABSTRACT

Este estudo objetivou traçar um perfil dos pacientes atendidos na sala de emergência do Pronto-Socorro de um hospital universitário do Rio Grande do Sul. Este estudo objetivou traçar um perfil dos pacientes atendidos na sala de emergência do Pronto-Socorro de um hospital universitário do Rio Grande do Sul. Estudo transversal com 47 pacientes selecionados por conveniência em que se aplicou um formulário semi-estruturado, contendo variáveis sociodemográficos e relacionadas ao atendimento. A coleta de dados ocorreu em setembro e outubro de 2009. Os dados foram organizados no programa Excel, utilizando-se análise estatística descritiva. Evidenciou-se que 74,5% das pessoas atendidas são do sexo masculino, na faixa etária de 31 a 60 anos (48,9%), casados (61,7%) e com ensino fundamental incompleto (70,2%). A principal causa de atendimento foi por trauma leve (31,9%) e Acidente Vascular Cerebral (8,5%), predominantemente no turno da tarde (49%). A maioria das pessoas atendidas (92%) permaneceu internada no pronto-socorro. O conhecimento do perfil dos pacientes atendidos contribui para o planejamento e execução de ações que visem atender ao ser humano com qualidade.


The following study aims to set a profile of the patients in the emergency room of a university hospital. It is a descriptive field study with a quantitative approach in which a semi-structured survey with socio-demographic variables has been applied and related to the service. The data collection happened from August to October of 2009. The data were organized in Excel, using a descriptive statistical analysis. It is highlighted that 74.5% of the people attended to are male, at an age group ranging from 31 to 60 years old (48.9%), married (61.7%), and with incomplete elementary school (70.2%). The main causes for service were mild trauma (31.9%) and stroke (8.5%), predominantly in the afternoon shift (49%). Most of the people attended (92%) kept hospitalized in the emergency room. The knowledge on the profile of patients attended contributes for the planning and executions of actions aiming to effectively serve the human being with quality.


Este estudio tiene como objetivo trazar un perfil de los pacientes atendidos en la sala de emergencia del Servicio de Emergencias de un hospital universitario. Se trata de un estudio de campo, descriptivo, con un abordaje cualitativo en el cual se aplicó un formulario semi-estructurado con variables socio demográficas y relacionadas con la atención. La recolección de datos se hizo en el periodo de agosto hasta octubre de 2009. Se ordenaron los datos en el programa Excel, utilizándose el análisis estadístico descriptivo. Se evidenció que el 74,5% de las personas atendidas son del sexo masculino, en la franja de edad comprendida entre 31 a 60 años (el 48,9%), casados (el 67,7%) y con la enseñanza primaria incompleta (el 70,2%). La principal causa de la atención fue un trauma suave (el 31,9%) y Accidente Vascular Cerebral (el 8,5%), predominantemente en el turno de la tarde (el 49%). La mayoría de las personas atendidas (el 92%) permanecieron internadas en el centro de emergencias. El conocimiento del perfil de los pacientes atendidos contribuye a la planificación y a la ejecución de acciones que tengan el objetivo de atender al ser humano con calidad.


Subject(s)
Humans , Emergency Nursing , Health Profile , Emergency Service, Hospital
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