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1.
Chemosphere ; 357: 142092, 2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38653396

RESUMO

Climate change further the world's human population increase is a mainstream political issue, and it's critical to search for solutions to produce enough food to feed everyone. Pesticides and fertilizers have been used as an easy solution to prevent pests and increase food production. Nevertheless, their overuse has dangerous effects on the ecosystems and communities. Oxyfluorfen (Oxy) and copper (Cu) based formulations are used as pesticides and widely applied on agricultural fields for crop protection. However, they have shown negative effects on non-target species. So, this work proposes to: a)determine the lethal concentration of Oxy and Cu to the zooplankton, Artemia franciscana, at different temperatures (15 °C, 20 °C and 25 °C); b)understand the biochemical impacts of these chemicals at the different temperatures scenarios, on A. franciscana and c)evaluate the impact of the climate changes, particularly the temperature increase, on this species sensitivity to the tested pesticides. Acute and sub-lethal bioassays with Oxy and Cu were performed at different temperatures to determine the lethal concentration of each chemical and to understand the effects of the compounds at different temperatures on the biochemical profiles of A. franciscana. Results showed an increase in chemicals toxicity with the temperature, and Oxy was revealed to be more noxious to A. franciscana than Cu; at a biochemical level, significant differences were observed among temperatures, with the biggest differences between the organisms exposed to 15 °C and 25 °C. Overall, a decrease in fatty acids (FA) and sugars was observed with the increase in Cu and oxyfluorfen concentrations. Different trends were observed with temperature increase, with FA increase in the organisms exposed to Cu and the opposite was observed in the ones exposed to oxyfluorfen. Sugar content decreases in the organisms exposed to oxyfluorfen with temperature increase and showed a non-linear behaviour in the ones exposed to Control and Cu treatments.

2.
Hipertens. riesgo vasc ; 41(1): 58-61, Ene-Mar, 2024. ilus
Artigo em Inglês | IBECS | ID: ibc-231667

RESUMO

Atropine, a competitive antagonist of acetylcholine muscarinic receptors, is commonly used to treat severe bradycardia by blocking parasympathetic activity. We present a rare case of hypertensive emergency following atropine administration, with only one previous report in the literature. A 78-year-old woman with essential hypertension and hypercholesterolemia was admitted to the cardiac intensive care unit for non-ST segment elevation myocardial infarction. During coronary angiography, an occlusion of the right coronary artery was identified. While removing the diagnostic catheter through the right radial artery, the patient experienced intense pain and discomfort, accompanied by a vasovagal reflex characterized by bradycardia and hypotension. Intravenous atropine (0.5mg) was administered, leading to a rapid rise in heart rate with frequent ventricular ectopy. Subsequently, a progressive and exaggerated elevation in arterial blood pressure occurred, peaking at 294/121mmHg approximately 10min after atropine administration. The patient developed hypertensive acute pulmonary edema, successfully treated with intravenous nitroglycerine (10mg) and furosemide (60mg). Blood pressure normalized after approximately 14min. The exact mechanism of atropine-induced hypertensive emergency remains unknown. While hypertensive emergencies with atropine are exceedingly rare, healthcare professionals should be aware of this potential effect and be prepared for prompt intervention.(AU)


La atropina, un antagonista competitivo de los receptores muscarínicos de acetilcolina, se utiliza comúnmente para tratar la bradicardia severa al bloquear la actividad parasimpática. Presentamos un caso raro de emergencia hipertensiva después de la administración de atropina, con solo un informe previo en la literatura. Una mujer de 78 años con hipertensión esencial e hipercolesterolemia fue ingresada en la unidad de cuidados intensivos cardíacos por infarto agudo de miocardio sin elevación del segmento ST. Durante la angiografía coronaria, se identificó una oclusión de la arteria coronaria derecha. Mientras se retiraba el catéter diagnóstico a través de la arteria radial derecha, la paciente experimentó un intenso dolor y malestar, acompañado de un reflejo vasovagal caracterizado por bradicardia e hipotensión. Se administró atropina intravenosa (0,5 mg), lo que provocó un rápido aumento de la frecuencia cardíaca con frecuente ectopia ventricular. Posteriormente, ocurrió una elevación progresiva y exagerada de la presión arterial, alcanzando un máximo de 294/121 mmHg aproximadamente 10 minutos después de la administración de atropina. La paciente desarrolló edema pulmonar agudo hipertensivo, tratado con éxito con nitroglicerina intravenosa (10 mg) y furosemida (60 mg). La presión arterial se normalizó después de aproximadamente 14 minutos. El mecanismo exacto de la emergencia hipertensiva inducida por atropina sigue siendo desconocido. Aunque las emergencias hipertensivas con atropina son excepcionalmente raras, los profesionales de la salud deben estar al tanto de este efecto potencial y estar preparados para intervenir rápidamente.(AU)


Assuntos
Humanos , Feminino , Idoso , Atropina/administração & dosagem , Atropina/efeitos adversos , Bradicardia , Hipercolesterolemia , Angiografia Coronária , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Pacientes Internados , Exame Físico , Hipertensão , Pressão Arterial
3.
Hipertens Riesgo Vasc ; 41(1): 58-61, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38403566

RESUMO

Atropine, a competitive antagonist of acetylcholine muscarinic receptors, is commonly used to treat severe bradycardia by blocking parasympathetic activity. We present a rare case of hypertensive emergency following atropine administration, with only one previous report in the literature. A 78-year-old woman with essential hypertension and hypercholesterolemia was admitted to the cardiac intensive care unit for non-ST segment elevation myocardial infarction. During coronary angiography, an occlusion of the right coronary artery was identified. While removing the diagnostic catheter through the right radial artery, the patient experienced intense pain and discomfort, accompanied by a vasovagal reflex characterized by bradycardia and hypotension. Intravenous atropine (0.5mg) was administered, leading to a rapid rise in heart rate with frequent ventricular ectopy. Subsequently, a progressive and exaggerated elevation in arterial blood pressure occurred, peaking at 294/121mmHg approximately 10min after atropine administration. The patient developed hypertensive acute pulmonary edema, successfully treated with intravenous nitroglycerine (10mg) and furosemide (60mg). Blood pressure normalized after approximately 14min. The exact mechanism of atropine-induced hypertensive emergency remains unknown. While hypertensive emergencies with atropine are exceedingly rare, healthcare professionals should be aware of this potential effect and be prepared for prompt intervention.


Assuntos
Hipertensão , 60458 , Feminino , Humanos , Idoso , Atropina/efeitos adversos , Bradicardia/induzido quimicamente , Hipertensão/tratamento farmacológico , Frequência Cardíaca
5.
Phys Rev Lett ; 128(24): 247203, 2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35776483

RESUMO

A chiral spin soliton lattice (CSL), one of the representative systems of a magnetic superstructure, exhibits reconfigurability in periodicity over a macroscopic length scale. Such coherent and tunable characteristics of the CSL lead to an emergence of elementary excitation of the CSL as phononlike modes due to translational symmetry breaking and bring a controllability of the dispersion relation of the CSL phonon. Using a broadband microwave spectroscopy technique, we directly found that higher-order magnetic resonance modes appear in the CSL phase of a chiral helimagnet CrNb_{3}S_{6}, which is ascribed to the CSL phonon response. The resonance frequency of the CSL phonon can be tuned between 16 and 40 GHz in the vicinity of the critical field, where the CSL period alters rapidly. The frequency range of the CSL phonon is expected to extend over 100 GHz as extrapolated on the basis of the theoretical model. The present results indicate that chiral helimagnets could work as materials useful for broadband signal processing in the millimeter-wave band.

6.
Sci Total Environ ; 800: 149473, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34392214

RESUMO

Wildfire effects go beyond direct impact in terrestrial ecosystems. Specifically, the periphytic communities of aquatic ecosystems standing within and downstream the burnt areas are relevant ecological receptors of post-fire runoff contamination. Nevertheless, the off-site impacts of wildfires in these communities are limitedly studied so far. The present study aimed to assess the effects of river water contaminated with ash-loaded runoff in the growth benthic diatom Navicula libonensis (Schoeman 1970). Four surface water samples were collected approximately one year after the wildfire for laboratory testing with the diatom: one was collected from a site upstream the burnt area, within the Unhais river (UU); three were collected from sites standing within the burnt area, one in the Unhais river (UB) and two in the Zêzere river (Z1 and Z2), reflecting different hydrological regimes. N. libonensis was proven able to discriminate among river sites affected and unaffected by wildfire runoff, reflecting, in general, the expected trends considering the physico-chemical characterization of the water samples. The water samples from the sites standing within the burnt area inhibited the biomass yield and growth rate of the tested diatom, ranking the samples regarding toxicity as follows: Z1 > UB > Z2 > UU. However, UB rather than Z1 presented the highest contaminant burden, namely metal elements, and some were found above widely accepted safety benchmarks (polycyclic aromatic hydrocarbons were not detected). This inconsistency can be linked to unknown interactions among metals within each water sample, to differential nutrient enrichment of samples, as well as hydrological factors. Overall, our results suggest that monospecific laboratory assays with sensitive diatoms can be valuable as cost-effective screening tools to prioritize sites affected by wildfires runoff requiring in-depth monitoring of negative effects in benthic producer communities.


Assuntos
Diatomáceas , Poluentes Químicos da Água , Incêndios Florestais , Ecossistema , Monitoramento Ambiental , Rios , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
7.
AJNR Am J Neuroradiol ; 42(5): 961-968, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33664107

RESUMO

BACKGROUND AND PURPOSE: Primary posterior fossa tumors comprise a large group of neoplasias with variable aggressiveness and short and long-term outcomes. This study aimed to validate the clinical usefulness of a radiologic decision flow chart based on previously published neuroradiologic knowledge for the diagnosis of posterior fossa tumors in children. MATERIALS AND METHODS: A retrospective study was conducted (from January 2013 to October 2019) at 2 pediatric referral centers, Children's Hospital of Philadelphia, United States, and Great Ormond Street Hospital, United Kingdom. Inclusion criteria were younger than 18 years of age and histologically and molecularly confirmed posterior fossa tumors. Subjects with no available preoperative MR imaging and tumors located primarily in the brain stem were excluded. Imaging characteristics of the tumors were evaluated following a predesigned, step-by-step flow chart. Agreement between readers was tested with the Cohen κ, and each diagnosis was analyzed for accuracy. RESULTS: A total of 148 cases were included, with a median age of 3.4 years (interquartile range, 2.1-6.1 years), and a male/female ratio of 1.24. The predesigned flow chart facilitated identification of pilocytic astrocytoma, ependymoma, and medulloblastoma sonic hedgehog tumors with high sensitivity and specificity. On the basis of the results, the flow chart was adjusted so that it would also be able to better discriminate atypical teratoid/rhabdoid tumors and medulloblastoma groups 3 or 4 (sensitivity = 75%-79%; specificity = 92%-99%). Moreover, our adjusted flow chart was useful in ruling out ependymoma, pilocytic astrocytomas, and medulloblastoma sonic hedgehog tumors. CONCLUSIONS: The modified flow chart offers a structured tool to aid in the adjunct diagnosis of pediatric posterior fossa tumors. Our results also establish a useful starting point for prospective clinical studies and for the development of automated algorithms, which may provide precise and adequate diagnostic tools for these tumors in clinical practice.


Assuntos
Algoritmos , Neoplasias Infratentoriais/diagnóstico , Imageamento por Ressonância Magnética/métodos , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Neoplasias Infratentoriais/patologia , Masculino
8.
Scand J Surg ; 110(2): 130-138, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33724090

RESUMO

BACKGROUND AND AIMS: There are increasing reports on case series on spontaneous isolated mesenteric artery dissection, that is, dissections of the superior mesenteric artery and celiac artery, mainly due to improved diagnostic capacity of high-resolution computed tomography angiography performed around the clock. A few case-control studies are now available, while randomized controlled trials are awaited. MATERIAL AND METHODS: The present systematic review based on 97 original studies offers a comprehensive overview on risk factors, management, conservative therapy, morphological modeling of dissection, and prognosis. RESULTS AND CONCLUSIONS: Male gender, hypertension, and smoking are risk factors for isolated mesenteric artery dissection, while the frequency of diabetes mellitus is reported to be low. Large aortomesenteric angle has also been considered to be a factor for superior mesenteric artery dissection. The overwhelming majority of patients can be conservatively treated without the need of endovascular or open operations. Conservative therapy consists of blood pressure lowering therapy, analgesics, and initial bowel rest, whereas there is no support for antithrombotic agents. Complete remodeling of the dissection after conservative therapy was found in 43% at mid-term follow-up. One absolute indication for surgery and endovascular stenting of the superior mesenteric artery is development of peritonitis due to bowel infarction, which occurs in 2.1% of superior mesenteric artery dissections and none in celiac artery dissections. The most documented end-organ infarction in celiac artery dissections is splenic infarctions, which occurs in 11.2%, and is a condition that should be treated conservatively. The frequency of ruptured pseudoaneurysm in the superior mesenteric artery and celiac artery dissection is very rare, 0.4%, and none of these patients were in shock at presentation. Endovascular therapy with covered stents should be considered in these patients.


Assuntos
Artérias Mesentéricas , Procedimentos Cirúrgicos Vasculares , Dissecação , Humanos , Masculino , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
9.
Braz J Med Biol Res ; 54(3): e10504, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33503201

RESUMO

Molecular changes that affect mitochondrial glycolysis have been associated with the maintenance of tumor cells. Some metabolic factors have already been described as predictors of disease severity and outcomes. This systematic review was conducted to answer the question: Is the glycolytic pathway correlated with the prognosis of oral squamous cell carcinoma (OSCC)? A search strategy was developed to retrieve studies in English from PubMed, Scopus, and ISI Web of Science using keywords related to squamous cell carcinoma, survival, and glycolytic pathway, with no restriction of publication date. The search retrieved 1273 publications. After the titles and abstracts were analyzed, 27 studies met inclusion criteria. Studies were divided into groups according to two subtopics, glycolytic pathways and diagnosis, which describe the glycolytic profile of OSCC tumors. Several components of tumor energy metabolism found in this review are important predictors of survival of patients with OSCC.


Assuntos
Glicólise , Neoplasias Bucais/diagnóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico , Humanos , Neoplasias Bucais/metabolismo , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo
10.
Toxicology ; 451: 152684, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33508380

RESUMO

The neurotoxicity and developmental effects of a widely applied insecticide (methomyl) was investigated by a multi-level approach (behavior and biometry, biochemical alterations and neurodegeneration) in Caenorhabditis elegans upon a short-term exposure (1 h) and a post-exposure period (48 h). The 1-h exposure to sub-lethal concentrations of methomyl (lower than 0.320 g L-1; i.e. below the estimated LC10) triggered significant changes on motor behavior and development impairment. The type of movement was significantly altered in methomyl-exposed worms, as well as biometric parameters (worms frequently idle and moving more backwards than controls; small body area, length and wavelength). These effects were followed by an increase of acetylcholine levels. Interestingly, after the 48-h recovery period, movement of previously exposed worms was similar to controls, and a concentration-dependent reversion of biometric endpoints was recorded, pointing out the transient action of the carbamate in line with an apparent absence of cholinergic neurons damage. This study provided new insight on the neurotoxicity of methomyl by showing that effects on movement and development were transient, and apparently did not result in neurodegeneration in cholinergic neurons. Moreover, these findings reinforced the advantages of using C. elegans in a multi-level approach for pesticide effects assessment.


Assuntos
Carbamatos/toxicidade , Neurônios Colinérgicos/efeitos dos fármacos , Inseticidas/toxicidade , Metomil/toxicidade , Atividade Motora/efeitos dos fármacos , Degeneração Neural/induzido quimicamente , Animais , Animais Geneticamente Modificados , Caenorhabditis elegans , Neurônios Colinérgicos/metabolismo , Neurônios Colinérgicos/patologia , Relação Dose-Resposta a Droga , Atividade Motora/fisiologia , Degeneração Neural/metabolismo , Degeneração Neural/patologia
11.
AJNR Am J Neuroradiol ; 42(2): 389-396, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33384291

RESUMO

BACKGROUND AND PURPOSE: Little is known about imaging features of spinal cord lesions in mitochondrial disorders. The aim of this research was to assess the frequency, imaging features, and pathogenic variants causing primary mitochondrial disease in children with spinal cord lesions. MATERIALS AND METHODS: This retrospective analysis included patients seen at Children's Hospital of Philadelphia between 2000 and 2019 who had a confirmed diagnosis of a primary (genetic-based) mitochondrial disease and available MR imaging of the spine. The MR imaging included at least both sagittal and axial fast spin-echo T2-weighted images. Spine images were independently reviewed by 2 neuroradiologists. Location and imaging features of spinal cord lesions were correlated and tested using the Fisher exact test. RESULTS: Of 119 children with primary mitochondrial disease in whom MR imaging was available, only 33 of 119 (28%) had available spine imaging for reanalysis. Nineteen of these 33 individuals (58%) had evidence of spinal cord lesions. Two main patterns of spinal cord lesions were identified: group A (12/19; 63%) had white ± gray matter involvement, and group B (7/19; 37%) had isolated gray matter involvement. Group A spinal cord lesions were similar to those seen in patients with neuromyelitis optica spectrum disorder, multiple sclerosis, anti-myelin oligodendrocyte glycoprotein-IgG antibody disease, and leukoencephalopathy with brain stem and spinal cord involvement and lactate elevation. Group B patients had spinal cord findings similar to those that occur with ischemia and viral infections. Significant associations were seen between the pattern of lesions (group A versus group B) and the location of lesions in cervical versus thoracolumbar segments, respectively (P < .01). CONCLUSIONS: Spinal cord lesions are frequently observed in children with primary mitochondrial disease and may mimic more common causes such as demyelination and ischemia.


Assuntos
Doenças Mitocondriais/patologia , Neuroimagem/métodos , Medula Espinal/diagnóstico por imagem , Medula Espinal/patologia , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Humanos , Lactente , Inflamação/diagnóstico , Inflamação/patologia , Isquemia/diagnóstico , Isquemia/patologia , Imageamento por Ressonância Magnética/métodos , Masculino , Estudos Retrospectivos , Doenças da Medula Espinal/diagnóstico , Doenças da Medula Espinal/etiologia , Doenças da Medula Espinal/patologia
12.
Neth Heart J ; 29(2): 111-112, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32394369
13.
Neth Heart J ; 29(2): 115-116, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32394370
14.
Braz. j. med. biol. res ; 54(3): e10504, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1153517

RESUMO

Molecular changes that affect mitochondrial glycolysis have been associated with the maintenance of tumor cells. Some metabolic factors have already been described as predictors of disease severity and outcomes. This systematic review was conducted to answer the question: Is the glycolytic pathway correlated with the prognosis of oral squamous cell carcinoma (OSCC)? A search strategy was developed to retrieve studies in English from PubMed, Scopus, and ISI Web of Science using keywords related to squamous cell carcinoma, survival, and glycolytic pathway, with no restriction of publication date. The search retrieved 1273 publications. After the titles and abstracts were analyzed, 27 studies met inclusion criteria. Studies were divided into groups according to two subtopics, glycolytic pathways and diagnosis, which describe the glycolytic profile of OSCC tumors. Several components of tumor energy metabolism found in this review are important predictors of survival of patients with OSCC.


Assuntos
Humanos , Neoplasias Bucais/diagnóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico , Glicólise , Neoplasias Bucais/metabolismo , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo
16.
Polymers (Basel) ; 12(11)2020 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-33202587

RESUMO

Poly (lactic acid) (PLA), due to its biodegradability, biocompatibility, and renewability, is one of the most promising biobased polymers for replacing some of the petrol-based materials. Low flexibility of PLA is overcome, by blending it with olefin-based polymers, such as polypropylene (PP). However, the use of compatibilizing agents is required to attain final materials with suitable mechanical properties. Such agents, although essential, can affect PLA structure and, consequently, the mechanical properties of the PLA. To the best of our knowledge, this issue was never studied, and the results can contribute to achieving the best formulations of PLA-based blends according to their final applications. The thermal and mechanical properties of the extruded PLA, with three different commercial compatibilizing agents, were evaluated with the purpose of demonstrating how the compatibilizers can introduce structural differences into the PLA chain during the extrusion process. The combination of crystallinity, molecular weight, and the morphology of the samples after extrusion determines the final mechanical properties of PLA. Despite being a fundamental study, it is our aim to contribute to the sustainability of PLA-based industries. The addition of a 2.5% concentration of C1 compatibilizer seems to have less influence on the final morphology and mechanical properties of the blends.

17.
Proc Natl Acad Sci U S A ; 117(45): 28183-28190, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-33109722

RESUMO

The idea that tropical forest and savanna are alternative states is crucial to how we manage these biomes and predict their future under global change. Large-scale empirical evidence for alternative stable states is limited, however, and comes mostly from the multimodal distribution of structural aspects of vegetation. These approaches have been criticized, as structure alone cannot separate out wetter savannas from drier forests for example, and there are also technical challenges to mapping vegetation structure in unbiased ways. Here, we develop an alternative approach to delimit the climatic envelope of the two biomes in Africa using tree species lists gathered for a large number of forest and savanna sites distributed across the continent. Our analyses confirm extensive climatic overlap of forest and savanna, supporting the alternative stable states hypothesis for Africa, and this result is corroborated by paleoecological evidence. Further, we find the two biomes to have highly divergent tree species compositions and to represent alternative compositional states. This allowed us to classify tree species as forest vs. savanna specialists, with some generalist species that span both biomes. In conjunction with georeferenced herbarium records, we mapped the forest and savanna distributions across Africa and quantified their environmental limits, which are primarily related to precipitation and seasonality, with a secondary contribution of fire. These results are important for the ongoing efforts to restore African ecosystems, which depend on accurate biome maps to set appropriate targets for the restored states but also provide empirical evidence for broad-scale bistability.


Assuntos
Clima , Ecossistema , Florestas , Pradaria , África , Incêndios , Chuva , Estações do Ano , Árvores , Clima Tropical
18.
Oper Dent ; 45(6): E308-E316, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32516396

RESUMO

CLINICAL RELEVANCE: Bulk-fill materials show a similar or better performance than control flowable materials regarding interfacial integrity. However, some self-adhesive composites need improvements to achieve competitive performance. SUMMARY: Objective: This laboratory study compared the polymerization stress and gap formation of self-adhesive, bulk-fill and control flowable composites. The degree of conversion (DC) and post-gel shrinkage were also assessed.Methods: Two self-adhesive (Vertise Flow and Fusio Liquid Dentin), two bulk-fill (Tetric N-Flow Bulk-Fill and Filtek Bulk-Fill Flowable Restorative), and two control flowable (Z350 XT Flowable Restorative and Tetric N-Flow) composites were evaluated. Polymerization stress (PS) was determined in a universal testing machine (n=5). Gap formation was evaluated by scanning electron microscopy in class I restorations (n=6). DC was measured by Fourier transform infrared spectroscopy (n=3). Post-gel volumetric shrinkage (VS) was measured using the strain gauge method (n=5). Data were submitted to one-way analysis of variance or a Kruskal-Wallis test (α=0.05).Results: Vertise Flow and Fusio Liquid Dentin presented the highest interfacial gap (27%±5% and 21%±6%, respectively), which was associated with their highest PS (4.1±0.8 MPa and 3.5±0.6 MPa, respectively) and DC (63%±2% and 60%±2%, respectively) in spite of the lowest VS (1.0%±0.2% and 1.0%±0.3%, respectively). Tetric N-Flow Bulk-Fill and Filtek Bulk-Fill Flowable Restorative presented similar PS (2.9± 0.3 MPa and 2.4±0.2 MPa, respectively) to both control materials. However, the Tetric N-Flow Bulk-Fill showed the lowest gap (7%±2%) and the highest DC (64.3%±0.4%), and the Filtek Bulk-fill presented a marginal gap (17.8%±3.4%) and a DC (54.5%±2.7%) similar to the control materials. The VS values of both bulk-fill materials were similar to those of Tetric N-Flow and lower than that of Z350 XT Flowable Restorative.Conclusions: Bulk-fill composites showed either similar or significantly lower interfacial gaps and PS than the control flowable composites. The self-adhesive composites showed a significantly higher gap percentage and PS than the control and bulk-fill materials.


Assuntos
Materiais Dentários , Cimentos de Resina , Resinas Compostas , Cimentos Dentários , Análise do Estresse Dentário , Teste de Materiais , Polimerização
19.
AJNR Am J Neuroradiol ; 41(5): 917-922, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32381541

RESUMO

Pathogenic variants in the polymerase γ gene (POLG) cause a diverse group of pathologies known as POLG-related disorders. In this report, we describe brain MR imaging findings and electroencephalogram correlates of 13 children with POLG-related disorders at diagnosis and follow-up. At diagnosis, all patients had seizures and 12 had abnormal MR imaging findings. The most common imaging findings were unilateral or bilateral perirolandic (54%) and unilateral or bilateral thalamic signal changes (77%). Association of epilepsia partialis continua with perirolandic and thalamic signal changes was present in 86% and 70% of the patients, respectively. The occipital lobe was affected in 2 patients. On follow-up, 92% of the patients had disease progression or fatal outcome. Rapid volume loss was seen in 77% of the patients. The occipital lobe (61%) and thalamus (61%) were the most affected brain regions. Perirolandic signal changes and seizures may represent a brain imaging biomarker of early-onset pediatric POLG-related disorders.


Assuntos
Encéfalo/diagnóstico por imagem , Doenças Mitocondriais/diagnóstico por imagem , Neuroimagem/métodos , Convulsões/diagnóstico por imagem , Convulsões/genética , Encéfalo/patologia , Criança , Pré-Escolar , DNA Polimerase gama/genética , Eletroencefalografia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Doenças Mitocondriais/genética , Doenças Mitocondriais/patologia , Estudos Retrospectivos , Convulsões/patologia
20.
MethodsX ; 7: 100785, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32025505

RESUMO

The methodology used to extract and quantify microplastics (MPs) in aquatic systems are still not standardized. Salt saturated solutions, such as sodium chloride (NaCl), zinc chloride (ZnCl2) and/or sodium iodide (NaI), are normally added to separate dense plastics from aquatic samples. However, the most effective reagents are also the most expensive (e.g. ZnCl2 and NaI). To decrease this cost, a reuse process of the salt solutions should be applied. The reuse process has been widely investigated for the NaI solution neglecting the ZnCl2. Hence, the aim of this study was to present a simple methodology to reuse the ZnCl2 solution ensuring the efficiency of the product. Results of the present study showed that ZnCl2 solution could be reused at least five times maintaining an efficiency above 95 %. •The ZnCl2 reuse decreases the cost of the methodology.•The efficiency of ZnCl2 solution after five filtrations remains above 95 % (all polymers are detected and recovered).•The use of this salt solution is the most cost-effective methodology to isolate MPs from aquatic samples.

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