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1.
Nature ; 623(7989): 927-931, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37968403

RESUMO

In recent years, certain luminous extragalactic optical transients have been observed to last only a few days1. Their short observed duration implies a different powering mechanism from the most common luminous extragalactic transients (supernovae), whose timescale is weeks2. Some short-duration transients, most notably AT2018cow (ref. 3), show blue optical colours and bright radio and X-ray emission4. Several AT2018cow-like transients have shown hints of a long-lived embedded energy source5, such as X-ray variability6,7, prolonged ultraviolet emission8, a tentative X-ray quasiperiodic oscillation9,10 and large energies coupled to fast (but subrelativistic) radio-emitting ejecta11,12. Here we report observations of minutes-duration optical flares in the aftermath of an AT2018cow-like transient, AT2022tsd (the 'Tasmanian Devil'). The flares occur over a period of months, are highly energetic and are probably nonthermal, implying that they arise from a near-relativistic outflow or jet. Our observations confirm that, in some AT2018cow-like transients, the embedded energy source is a compact object, either a magnetar or an accreting black hole.

2.
Part Fibre Toxicol ; 20(1): 4, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36650530

RESUMO

BACKGROUND: Acute phase response (APR) is characterized by a change in concentration of different proteins, including C-reactive protein and serum amyloid A (SAA) that can be linked to both exposure to metal oxide nanomaterials and risk of cardiovascular diseases. In this study, we intratracheally exposed mice to ZnO, CuO, Al2O3, SnO2 and TiO2 and carbon black (Printex 90) nanomaterials with a wide range in phagolysosomal solubility. We subsequently assessed neutrophil numbers, protein and lactate dehydrogenase activity in bronchoalveolar lavage fluid, Saa3 and Saa1 mRNA levels in lung and liver tissue, respectively, and SAA3 and SAA1/2 in plasma. Endpoints were analyzed 1 and 28 days after exposure, including histopathology of lung and liver tissues. RESULTS: All nanomaterials induced pulmonary inflammation after 1 day, and exposure to ZnO, CuO, SnO2, TiO2 and Printex 90 increased Saa3 mRNA levels in lungs and Saa1 mRNA levels in liver. Additionally, CuO, SnO2, TiO2 and Printex 90 increased plasma levels of SAA3 and SAA1/2. Acute phase response was predicted by deposited surface area for insoluble metal oxides, 1 and 28 days post-exposure. CONCLUSION: Soluble and insoluble metal oxides induced dose-dependent APR with different time dependency. Neutrophil influx, Saa3 mRNA levels in lung tissue and plasma SAA3 levels correlated across all studied nanomaterials, suggesting that these endpoints can be used as biomarkers of acute phase response and cardiovascular disease risk following exposure to soluble and insoluble particles.


Assuntos
Nanoestruturas , Óxido de Zinco , Camundongos , Animais , Reação de Fase Aguda/induzido quimicamente , Óxido de Zinco/toxicidade , Óxido de Zinco/metabolismo , Pulmão/metabolismo , Nanoestruturas/toxicidade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
3.
BMC Ophthalmol ; 23(1): 216, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37189079

RESUMO

BACKGROUND: To describe the ocular features of a cohort of children with Down Syndrome (DS) in Bogotá, Colombia. METHODS: We performed a cross-sectional study, evaluating 67 children with DS. A pediatric ophthalmologist performed a complete optometric and ophthalmological evaluation of each child, including visual acuity, ocular alignment, external eye examination, biomicroscopy, auto-refractometry, retinoscope in cycloplegia, and fundus examination. Results were reported as frequency distribution tables with percentages for categorical variables and means and standard deviation or median and interquartile ranges for continuous variables, according to their distribution. We used the Chi-square test or Fisher's exact test for categorical variables and ANOVA or Kruskal-Wallis for continuous variables when indicated. RESULTS: A total of 134 eyes from 67 children were evaluated. Males represented 50.7%. The children's age ranged from 8-16 years, with a mean of 12.3 (SD 2.30). The most frequent refractive diagnosis per eye was hyperopia (47%), followed by myopia (32.1%) and mixed astigmatism (18.7%). The most frequent ocular manifestations were oblique fissure (89.6%), followed by amblyopia (54.5%) and lens opacity (39.4%). Female sex was associated with strabismus (P = 0.009) and amblyopia (P = 0.048). CONCLUSION: Our cohort had a high prevalence of disregarded ophthalmological manifestations. Some of these manifestations, such as amblyopia, can be irreversible and severely affect the neurodevelopment of DS children. Therefore, ophthalmologists and optometrists should be aware of the visual and ocular affection of children with DS to assess and provide appropriate management. This awareness could improve rehabilitation outcomes for these children.


Assuntos
Ambliopia , Síndrome de Down , Erros de Refração , Estrabismo , Masculino , Criança , Humanos , Feminino , Adolescente , Ambliopia/diagnóstico , Ambliopia/epidemiologia , Ambliopia/etiologia , Erros de Refração/diagnóstico , Colômbia/epidemiologia , Síndrome de Down/complicações , Síndrome de Down/epidemiologia , Estudos Transversais , Estrabismo/epidemiologia , Prevalência
4.
Can J Anaesth ; 70(11): 1776-1788, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37853279

RESUMO

PURPOSE: Myocardial injury after noncardiac surgery is common and mostly asymptomatic. The ideal target population that will benefit from routine troponin measurements in low and middle income countries (LMICs) is unclear. This study aims to evaluate the clinical outcomes of a cohort of high-risk surgical patients according to high-sensitivity troponin T (hsTnT) in an LMIC setting. METHODS: We conducted a prospective cohort study of 442 high-risk patients undergoing noncardiac surgery at a Brazilian hospital between February 2019 and March 2020. High-sensitivity troponin T levels were measured preoperatively, 24 hr, and 48 hr after surgery and stratified into three groups: normal (< 20 ng·L-1); minor elevation (20-65 ng·L-1); and major elevation (> 65 ng·L-1). We performed survival analysis to determine the association between myocardial injury and one-year mortality. We described medical interventions and evaluated unplanned intensive care unit (ICU) admission and complications using multivariable models. RESULTS: Postoperative myocardial injury occurred in 45% of patients. Overall, 30-day mortality was 8%. Thirty-day and one-year mortality were higher in patients with hsTnT ≥ 20 ng·L-1. One-year mortality was 18% in the unaltered troponin group vs 31% and 41% for minor and major elevation groups, respectively. Multivariable analysis of one-year survival showed a hazard ratio (HR) of 1.94 (95% confidence interval [CI], 1.22 to 3.09) for the minor elevation group and a HR of 2.73 (95% CI, 1.67 to 4.45) for the troponin > 65 ng·L-1 group. Patients with altered troponin had more unplanned ICU admissions (13% vs 5%) and more complications (78% vs 48%). CONCLUSION: This study supports evidence that hsTnT is an important prognostic marker and a strong predictor of all-cause mortality after surgery. Troponin measurement in high-risk surgical patients could potentially be used as tool to scale-up care in LMIC settings. STUDY REGISTRATION: ClinicalTrials.gov (NCT04187664); first submitted 5 December 2019.


RéSUMé: OBJECTIF: Les lésions myocardiques après une chirurgie non cardiaque sont courantes et la plupart du temps asymptomatiques. Nous ne connaissons pas la population cible idéale qui bénéficierait de mesures régulières de la troponine dans les pays à revenu faible et intermédiaire (PRFI). Cette étude vise à évaluer les issues cliniques d'une cohorte de patient·es de chirurgie à haut risque grâce à la troponine T à haute sensibilité (hsTnT) dans un contexte de PRFI. MéTHODE: Nous avons mené une étude de cohorte prospective auprès de 442 patient·es à haut risque bénéficiant d'une chirurgie non cardiaque dans un hôpital brésilien entre février 2019 et mars 2020. Les taux de troponine T à haute sensibilité ont été mesurés avant l'opération, 24 heures et 48 heures après la chirurgie, et stratifiés en trois groupes : normaux (< 20 ng·L−1), élévation mineure (20­65 ng·L−1) et élévation majeure (> 65 ng·L−1). Nous avons réalisé une analyse de survie pour déterminer l'association entre les lésions myocardiques et la mortalité à un an. Nous avons décrit les interventions médicales et évalué les admissions non planifiées à l'unité de soins intensifs (USI) ainsi que les complications à l'aide de modèles multivariables. RéSULTATS: Une lésion myocardique postopératoire est survenue chez 45 % des patient·es. La mortalité globale à 30 jours était de 8 %. La mortalité à trente jours et à un an était plus élevée chez les patient·es avec une hsTnT ≥ 20 ng·L−1. La mortalité à un an était de 18 % dans le groupe troponine inchangée vs 31 % et 41 % pour les groupes à élévation mineure et majeure de la troponine, respectivement. L'analyse multivariée de la survie à un an a montré un rapport de risque (RR) de 1,94 (intervalle de confiance [IC] à 95 %, 1,22 à 3,09) pour le groupe d'élévation mineure et un RR de 2,73 (IC 95 %, 1,67 à 4,45) pour le groupe avec une troponine > 65 ng·L−1. Les admissions non planifiées à l'USI étaient plus fréquentes chez les patient·es présentant une troponine altérée (13 % vs 5 %), tout comme les complications (78 % vs 48 %). CONCLUSION: Cette étude soutient les données probantes selon lesquelles la hsTnT est un marqueur pronostique important et un prédicteur fort de la mortalité toutes causes confondues après la chirurgie. La mesure de la troponine chez la patientèle chirurgicale à risque élevé pourrait potentiellement être utilisée comme outil pour intensifier les soins dans les PRFI. ENREGISTREMENT DE L'éTUDE: ClinicalTrials.gov (NCT04187664); soumis pour la première fois le 5 décembre 2019.


Assuntos
Países em Desenvolvimento , Troponina , Humanos , Troponina T , Estudos Prospectivos , Medição de Risco , Biomarcadores
5.
Int J Educ Dev ; 101: 102835, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37361921

RESUMO

This systematic review describes the effects of COVID-19 lockdowns on children's learning and school performance. A systematic search was conducted using three databases. A total of 1787 articles were found, and 24 articles were included. Overall, academic performance was negatively affected by COVID-19 lockdowns, with lower scores in standardized tests in the main domains compared to previous years. Academic, motivational, and socio-emotional factors contributed to lower performance. Educators, parents, and students reported disorganization, increased academic demands, and motivational and behavioral changes. Teachers and policymakers should consider these results in developing future education strategies.

6.
Curr Issues Mol Biol ; 44(5): 2054-2068, 2022 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-35678668

RESUMO

Cervical cancer (CC) is one of the most common cancers in women, and is linked to human papillomavirus (HPV) infection. The virus oncoprotein E6 binds to p53, resulting in its degradation and allowing uncontrolled cell proliferation. Meanwhile, the HPV E7 protein maintains host cell differentiation by targeting retinoblastoma tumor suppressor. The host cell can ubiquitinate E6 and E7 through UBE2L3, whose expression depends on the interaction between the aryl hydrocarbon receptor (AhR) with Xenobiotic Responsive Elements (XREs) located in the UBE2L3 gene promoter. In this study, we used cell culture to determine the effect of indole-3-carbinol (I3C) over cellular viability, apoptosis, cell proliferation, and mRNA levels of UBE2L3 and CYP1A1. In addition, patients' samples were used to determine the mRNA levels of UBE2L3 and CYP1A1 genes. We found that I3C promotes the activation of AhR and decreases cell proliferation, possibly through UBE2L3 mRNA induction, which would result in the ubiquitination of HPV E7. Since there is a strong requirement for selective and cost-effective cancer treatments, natural AhR ligands such as I3C could represent a novel strategy for cancer treatment.

7.
J Vector Borne Dis ; 59(1): 86-90, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35708409

RESUMO

The recently described Triatoma huehuetenanguensis, has been reported in Mexico, Guatemala, Belize and Honduras. In Mexico, the species has been collected primarily in rural areas; it has the potential to colonize human dwellings, however, its contribution to Chagas outbreaks remains unclear. In 2021, T. huehuetenanguensis was first observed at Tuxtla Gutierrez city, Chiapas; then a collection for the species was performed. A total of 308 houses were inspected in the intra and peridomestic structures. Only 3 houses (0.97%) were infested. Triatoma huehuetenangensis was the only triatomine specie recorded and four males were collected. None of the bugs tested positive for Trypanosoma infection. We do not have evidence to suggest that urban human-vector contact still limited, and a possible domestication process is possible. The presence of reservoirs, the vector species and the parasite demonstrate that Tuxtla Gutierrez could be at risk of a Chagas disease outbreak.


Assuntos
Doença de Chagas , Triatoma , Trypanosoma cruzi , Animais , Doença de Chagas/epidemiologia , Humanos , Insetos Vetores/parasitologia , Masculino , México/epidemiologia , Triatoma/parasitologia
8.
Rev Argent Microbiol ; 54(4): 293-298, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35725665

RESUMO

The aim of this study was to characterize phenotypically and genotypically 27 mecA positive Staphylococcus aureus strains with oxacillin MICs of ≤2µg/ml by Vitek 2, isolated in different regions of Uruguay. Susceptibility to oxacillin and cefoxitin was studied by gradient diffusion, disk diffusion to cefoxitin, and Phoenix and MicroScan systems. PBP2a was determined. SCCmec typing was performed and the isolates were compared by PFGE. Twenty-six isolates were susceptible to oxacillin; one strain was susceptible to cefoxitin by disk diffusion and 3 strains by gradient diffusion. Phoenix and MicroScan panels detected methicillin resistance in 25 and 27 strains, respectively. Twenty-six strains tested positive for PBP2a. Twenty-six strains carried SCCmec V and 24 belonged to pulsotype A. One strain carried SCCmec IV and did not belong to pulsotype A. Cefoxitin disk diffusion test and PBP2a detection correctly identified 26 of these 27 strains as MRSA. PFGE results suggest the dissemination of a cluster of MRSA carrying SCCmec V.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Humanos , Oxacilina/farmacologia , Staphylococcus aureus , Cefoxitina/farmacologia , Uruguai , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Testes de Sensibilidade Microbiana , Staphylococcus aureus Resistente à Meticilina/genética
9.
BMC Neurosci ; 22(1): 60, 2021 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-34627165

RESUMO

BACKGROUND: Autism spectrum disorder (ASD) is a complex neurodevelopmental condition characterized by persistent deficits in social communication and interaction. Common genetic variation appears to play a key role in the development of this condition. In this systematic review, we describe the relationship between genetic variations and autism. We created a gene dataset of the genes involved in the pathogenesis of autism and performed an over-representation analysis to evaluate the biological functions and molecular pathways that may explain the associations between these variants and the development of ASD. RESULTS: 177 studies and a gene set composed of 139 were included in this qualitative systematic review. Enriched pathways in the over-representation analysis using the KEGG pathway database were mostly associated with neurotransmitter receptors and their subunits. Major over-represented biological processes were social behavior, vocalization behavior, learning and memory. The enriched cellular component of the proteins encoded by the genes identified in this systematic review were the postsynaptic membrane and the cell junction. CONCLUSIONS: Among the biological processes that were examined, genes involved in synaptic integrity, neurotransmitter metabolism, and cell adhesion molecules were significantly involved in the development of autism.


Assuntos
Transtorno do Espectro Autista/genética , Predisposição Genética para Doença/genética , Aprendizagem/fisiologia , Polimorfismo Genético/genética , Testes Genéticos/métodos , Variação Genética/genética , Humanos
10.
Br J Anaesth ; 126(2): 525-532, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33127046

RESUMO

BACKGROUND: The development of feasible preoperative risk tools is desirable, especially for low-middle income countries with limited resources and complex surgical settings. This study aimed to derive and validate a preoperative risk model (Ex-Care model) for postoperative mortality and compare its performance with current risk tools. METHODS: A multivariable logistic regression model predicting in-hospital mortality was developed using a large Brazilian surgical cohort. Patient and perioperative predictors were considered. Its performance was compared with the Charlson comorbidity index (CCI), Revised Cardiac Risk Index (RCRI), and the Surgical Outcome Risk Tool (SORT). RESULTS: The derivation cohort included 16 618 patients. In-hospital death occurred in 465 patients (2.8%). Age, with adjusted splines, degree of procedure (major vs non-major), ASA physical status, and urgency were entered in a final model. It showed high discrimination with an area under the receiver operating characteristic curve (AUROC) of 0.926 (95% confidence interval [CI], 0.91-0.93). It had superior accuracy to the RCRI (AUROC, 0.90 vs 0.76; P<0.01) and similar to the CCI (0.90 vs 0.82; P=0.06) and SORT models (0.90 vs 0.92; P=0.2) in the temporal validation cohort of 1173 patients. Calibration was adequate in both development (Hosmer-Lemeshow, 9.26; P=0.41) and temporal validation cohorts (Hosmer-Lemeshow 5.29; P=0.71). CONCLUSIONS: The Ex-Care risk model proved very efficient at identifying high-risk surgical patients. Although multicentre studies are needed, it should have particular value in low resource settings to better inform perioperative health policy and clinical decision-making.


Assuntos
Técnicas de Apoio para a Decisão , Mortalidade Hospitalar , Procedimentos Cirúrgicos Operatórios/mortalidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil , Tomada de Decisão Clínica , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Medição de Risco , Fatores de Risco , Resultado do Tratamento , Adulto Jovem
11.
J Oral Maxillofac Surg ; 79(5): 1044.e1-1044.e12, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33359103

RESUMO

PURPOSE: Mandibular reconstitution with bioabsorbable scaffolds seems feasible with the application of 3-dimensional printing combined with bioactive proteins. As yet, previous studies have been limited in number of animals and have avoided a contaminated defect. We present a caprine model of mandibular defect bone regeneration with a 3-dimensionally printed bioabsorbable scaffold contaminated with oral secretions and explore the impact of bone morphogenic protein in mandibular bone reconstitution. METHODS: A 3-cm, contaminated mandibular defect was generated in 18 goats and stabilized with 2 mandibular reconstruction plates. An uncoated scaffold was placed in 6 goats, and in the final 6 goats, the scaffold was coated with bone morphogenic protein-2. In 6 goats, the defect was left empty. After 12 weeks, the operative site, scaffold, and adjacent mandible were plasticized, sectioned, and evaluated histologically to assess for bone regeneration. RESULTS: The specimens revealed only focal (average of 5.8% of the scaffold pores) and early bone formation in the scaffold-only group. In the scaffold + bone morphogenic protein-2 group, there was more (average of 51.4% of the pores) bone formation. In the periosteum-only group, the ratio of the bone thickness of the defect to that of the normal bone ranged from 0.16 to 0.78. No major infections occurred. CONCLUSIONS: This caprine model serves as an excellent method to assess reconstructive options for contaminated mandibular deficits. Bone regeneration was documented in a 3-cm contaminated caprine mandibular defect reconstructed with a 3-dimensionally printed synthetic scaffold with or without the addition of bone morphogenic protein-2. Bone morphogenic protein-2 significantly augments bone generation in the synthetic scaffold. Residual mandibular periosteum generated bone. Future studies will focus on optimizing vascularization.


Assuntos
Reconstrução Mandibular , Alicerces Teciduais , Animais , Regeneração Óssea , Cabras , Mandíbula/cirurgia , Osteogênese , Impressão Tridimensional
12.
Environ Sci Technol ; 54(22): 14432-14441, 2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-33156610

RESUMO

Triclosan is a high-production volume chemical, which has become widely detected in environmental systems because of its widespread usage. Photodegradation has been identified as a major degradation pathway, but the identified photoproducts are also chemicals of concern. In this study, lower chlorinated derivatives of triclosan were synthesized to investigate the impact the chlorine substituents have on the photodegradation rate and the photoproducts produced. In addition, the photodegradation of two classes of photoproducts-dibenzo-p-dioxins (DDs) and 2,2'-dihydroxylated biphenyls-was also investigated. Degradation of triclosan in near-surface sunlit waters was relatively fast (t1/2 < 5 h). Calculated degradation rates were slower for DDs and faster for dihydroxylated biphenyls in comparison to that for triclosan. In addition, the 2'-Cl substituent was critical for the high quantum yield measured for triclosan and necessary for the photodegradation mechanism that forms DDs and dihydroxylated biphenyls. The 4-Cl substituent was responsible for higher rates of light absorption and the environmentally relevant pKa. Without either of these substituents, the environmental fate of triclosan would be markedly different.


Assuntos
Triclosan , Poluentes Químicos da Água , Fotólise , Triclosan/análise , Poluentes Químicos da Água/análise
13.
Am J Otolaryngol ; 41(3): 102414, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32093975

RESUMO

PURPOSE: This study summarizes the treatment modalities of basal cell adenocarcinoma (BCAC) of the parotid gland and subsequent outcome at a single institution to better define the treatment of this rare tumor. MATERIAL AND METHODS: A retrospective review of patients treated for BCAC of the parotid gland from 1/01/1996 to 08/1/2018 was performed. Patients were identified using our institution's Cancer Registry. RESULTS: A total of thirteen patients (46% female, median age of 56) treated for BCAC of the parotid gland were identified. Eight patients (57%) were staged as T1, four were staged as T2 (29%), and two were stage T4a (14%) due to tumor involvement of the facial nerve. None of the patients had nodal involvement or distant metastases. Three patients (21%) underwent radiation therapy ranging from 60-70Gy for positive margin or facial nerve involvement by tumor. Five patients (36%) underwent a neck dissection (ND) ranging from just a level IIb dissection up to levels IIa, IIb, and III with none of the nodes being positive for disease. The remainder of patients did not undergo a neck dissection. Follow-up was 8.1 ± 6.2 (mean ± SD) years with no local or regional recurrence at time of last follow-up in any patient cohort. CONCLUSIONS: Our review suggests that elective neck dissections are not necessary following resection of T1/T2N0M0 basal cell adenocarcinoma for the prevention of local or regional recurrence. No longer performing neck dissections for T1/T2N0M0 BCAC would reduce the morbidity associated with the treatment of this rare parotid tumor.


Assuntos
Adenocarcinoma/radioterapia , Adenocarcinoma/cirurgia , Esvaziamento Cervical , Neoplasias Parotídeas/radioterapia , Neoplasias Parotídeas/cirurgia , Procedimentos Desnecessários , Adenocarcinoma/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Imagem de Difusão por Ressonância Magnética , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/prevenção & controle , Neoplasias Parotídeas/diagnóstico por imagem , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
14.
J Environ Manage ; 260: 110101, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32090818

RESUMO

The environmentally extended presence of triclosan, TCS, component of many pharmaceutical and personal care products, and its known persistent character have awoke the scientific and social concern leading to the study of effective remediation techniques. Advanced oxidation techniques stand out for the effectiveness in degrading many persistent compounds, and as a result, they have been addressed by many researchers. However, the powerful oxidation media might lead to the formation of undesirable by-products, concern that has also been widely addressed. With regard to the presence of TCS, photolytic and photocatalytic processes provide a very effective degradation yield and rate, with a large number of reports addressing its removal from different environmental matrices. But currently, there is no clear understanding of the mechanisms involved and the routes responsible for the formation of degradation products. Thus, this work presents an exhaustive and critical analysis of the state of the art related to the photo-degradation of TCS, with special focus on the formation of oxidation by-products, on the phenomena responsible and on the influence of operation variables. This report aims at offering valuable information to researchers dealing with this environmentally relevant problem.


Assuntos
Triclosan , Poluentes Químicos da Água , Oxirredução , Fotólise
15.
Behav Res Methods ; 52(3): 1008-1025, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31676967

RESUMO

Studies on morphological processing in French, as in other languages, have shown disparate results. We argue that a critical and long-overlooked factor that could underlie these diverging results is the methodological differences in the calculation of morphological variables across studies. To address the need for a common morphological database, we present MorphoLex-FR, a sizeable and freely available database with 12 variables for prefixes, roots, and suffixes for the 38,840 words of the French Lexicon Project. MorphoLex-FR constitutes a first step to render future studies addressing morphological processing in French comparable. The procedure we used for morphological segmentation and variable computation is effectively the same as that in MorphoLex, an English morphological database. This will allow for cross-linguistic comparisons of future studies in French and English that will contribute to our understanding of how morphologically complex words are processed. To validate these variables, we explored their influence on lexical decision latencies for morphologically complex nouns in a series of hierarchical regression models. The results indicated that only morphological variables related to the suffix explained lexical decision latencies. The frequency and family size of the suffix exerted facilitatory effects, whereas the percentage of more frequent words in the morphological family of the suffix was inhibitory. Our results are in line with previous studies conducted in French and in English. In conclusion, this database represents a valuable resource for studies on the effect of morphology in visual word processing in French.


Assuntos
Bases de Dados Factuais , Idioma , Cognição , Linguística
16.
Neurobiol Learn Mem ; 148: 1-7, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29277581

RESUMO

Pregnancy is a dynamic process during which significant cognitive changes take place. It has been suggested that working memory (WM) is affected during gestation as a result of functional changes among cortical areas, such as the prefrontal and parietal cortices. This study examined cortical electroencephalographic correlations (rEEG) during performance of WM tasks in each trimester of pregnancy. Forty women were divided into 4 groups: first (T1), second (T2), and third (T3) trimester of pregnancy, and a control group of non-pregnant women. Electroencephalographic activity (EEG) was recorded from the frontopolar, dorsolateral and parietal cortices during performance of one verbal and one visuospatial working memory task. Only groups T2 and T3 showed increased onset latency in the visuospatial WM. During the verbal WM task, the T1 group showed a higher correlation between dorsolateral areas in the theta and alpha bands, as well as a lower left prefrontal-parietal correlation in the gamma band. During the visuospatial WM task, the T1 and T3 groups showed a higher left EEG correlation in the delta and alpha1 bands, whereas T2 presented a higher right prefrontal-parietal correlation in the gamma band. Although pregnancy had only a subtle effect on the visuospatial WM task, these different patterns of cortical synchronization in each trimester of pregnancy could represent adaptive mechanisms that enabled the pregnant women to focus their attention and use more cognitive resources and so adequately solve the WM tasks.


Assuntos
Ondas Encefálicas/fisiologia , Sincronização Cortical/fisiologia , Memória de Curto Prazo/fisiologia , Lobo Parietal/fisiologia , Córtex Pré-Frontal/fisiologia , Desempenho Psicomotor/fisiologia , Aprendizagem Verbal/fisiologia , Adulto , Eletroencefalografia , Feminino , Humanos , Testes Neuropsicológicos , Gravidez , Percepção Espacial/fisiologia , Memória Espacial/fisiologia , Percepção Visual/fisiologia , Escalas de Wechsler , Adulto Jovem
18.
Int Orthop ; 42(1): 161-167, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28936610

RESUMO

INTRODUCTION: The most common reason for removal of well-fixed radial head prostheses is painful loosening. We hypothesised that short-stemmed prostheses, used for radial head arthroplasty, are not associated with an increased risk of implant loosening. METHODS: From 2002 to 2014, 65 patients were enrolled in a retrospective single-centre study. The radial head prostheses were classified as having either a long (30-mm) or short (16- to 22-mm) stem. The long-stemmed implants comprised 30 GUEPAR® DePuy Synthes (West Chester, PA, USA) and 20 Evolutive® Aston Medical (Saint-Etienne, France) devices; the short-stemmed implants comprised nine RECON and six STANDARD rHead® SBI-Stryker (Morrisville, PA, USA) devices. At last follow-up, clinical (range of motion, Disabilities of the Arm, Shoulder, and Hand score, Mayo Elbow Performance score) and radiographic (osteolysis) outcomes were assessed. RESULTS: At a mean follow-up of 76.78 months (24-141), the rate of painful loosening [6 (40%) vs 8 (16%), p = 0.047] and osteolysis [12 (80%) vs 23 (46%), p = 0.02] were significantly higher in patients with short-stemmed versus long-stemmed implants. Despite the significant difference in loosening between stems as groups, individual stem length was not determined. CONCLUSIONS: Tight-fitting implants with short stems are more prone to painful loosening.


Assuntos
Artroplastia/instrumentação , Articulação do Cotovelo/cirurgia , Prótese de Cotovelo/efeitos adversos , Falha de Prótese/efeitos adversos , Fraturas do Rádio/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Artroplastia/efeitos adversos , Artroplastia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteólise/epidemiologia , Osteólise/etiologia , Desenho de Prótese/efeitos adversos , Desenho de Prótese/métodos , Rádio (Anatomia)/cirurgia , Amplitude de Movimento Articular , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento
19.
Behav Res Methods ; 50(4): 1568-1580, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29124719

RESUMO

Most of the new words a reader will find are morphologically complex. Also, theoretical models of language processing propose that morphology plays an important role in visual word processing. Nevertheless, studies on the subject show contradicting results that are difficult to reconcile. One factor that may explain this is the lack of a sizeable and reliable morphological database. As a consequence, there are enormous methodological differences in the way the values for morphological variables are calculated across studies. We present a sizeable and freely available database with six new variables for affixes and three for roots for 68,624 words from the English Lexicon Project. We further studied by means of regression models the influence of these new variables on the lexical decision latencies of 4,724 morphologically complex nouns that included one root and one suffix. Results showed that root frequency and suffix length had a facilitatory effect, whereas the percentage of more frequent words in the morphological family of the suffix had an inhibitory effect on latencies. After controlling for collinearity, root family size, suffix family size, suffix P*, and suffix frequency also had facilitatory effects. These results shed new light on the importance of suffix length and the frequency of the lexical competitors of the family of a suffix. This database represents a valuable resource for studies on the effect of morphology in visual word processing in English and can be found at https://github.com/hugomailhot/MorphoLex-en .


Assuntos
Bases de Dados Factuais , Desenvolvimento da Linguagem , Idioma , Leitura , Adulto , Tomada de Decisões , Humanos , Psicolinguística , Reconhecimento Psicológico , Vocabulário
20.
J Nucl Cardiol ; 24(1): 308-316, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27572926

RESUMO

The burden of cardiovascular diseases (CVDs) in the world is ever growing. They represent the first cause of death worldwide and in Latin America. Nuclear cardiology has a well-established role in the management of patient with CVDs and is being increasingly integrated into the healthcare systems in the region. However, there remains variability as to the infrastructure available across the countries, in terms of existing technology, radiopharmaceuticals, and human resources. The approximate number of gamma (γ) cameras in the region is 1348, with an average of 2.25 per million population; Argentina and Brazil having the largest number. Nearly 80% of the existing cameras are single-photon emission tomography (SPECT), of which 8% are hybrid SPECT-CT systems. Positron emission tomography technology is steadily increasing, and currently, there is an average of 0.25 scanners per million inhabitants, indicating that there is a potential to expand the capacities in order to cover the needs. Four countries have nuclear reactors for research purposes, which allow the production of technetium-99 m (Argentina, Chile, Mexico and Peru), while four (Argentina, Brazil, Cuba, and Mexico) assemble 99Mo-99mTc generators. As for the nuclear cardiology studies, about 80% of studies performed are gated SPECT myocardial perfusion imaging; less than 10% are multi-gated acquisition (mainly for evaluation of cardiac toxicity in cancer patients), and the other 10% correspond to other types of studies, such as viability detection, and adrenergic innervation studies with 123I-MIBG. Physical stress is preferred, when possible, based on the clinical condition of the patient. Regarding human resources, there is an average of 1.1 physicians and 1.3 technologists per γ camera, with 0.1 medical physicists and 0.1 radiopharmacists per center in the region. The future of nuclear cardiology in Latin America and the Caribbean is encouraging, with great potential and possibilities for growth. National, regional, and international cooperation including support from scientific societies and organizations such as International Atomic Energy Agency, American Society of Nuclear Cardiology, and Latin American Association of Biology and Nuclear Medicine Societies, as well as governmental commitment are key factors for the development of the specialty. A multimodality approach in cardiac imaging will contribute to a better management of patients with CVDs.


Assuntos
Técnicas de Imagem Cardíaca/estatística & dados numéricos , Doenças Cardiovasculares/diagnóstico por imagem , Doenças Cardiovasculares/epidemiologia , Cintilografia/estatística & dados numéricos , Revisão da Utilização de Recursos de Saúde , Cardiologia/estatística & dados numéricos , Região do Caribe/epidemiologia , Humanos , América Latina/epidemiologia , Medicina Nuclear/estatística & dados numéricos , Prevalência
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