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1.
Front Cell Neurosci ; 18: 1414142, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38915876

RESUMO

Extracellular vesicles (EVs) are secreted by all cells in the CNS, including neurons and astrocytes. EVs are lipid membrane enclosed particles loaded with various bioactive cargoes reflecting the dynamic activities of cells of origin. In contrast to neurons, the specific role of EVs released by astrocytes is less well understood, partly due to the difficulty in maintaining primary astrocyte cultures in a quiescent state. The aim of this study was to establish a human serum-free astrocyte culture system that maintains primary astrocytes in a quiescent state to study the morphology, function, and protein cargoes of astrocyte-derived EVs. Serum-free medium with G5 supplement and serum-supplemented medium with 2% FBS were compared for the culture of commercially available human primary fetal astrocytes. Serum-free astrocytes displayed morphologies similar to in vivo astrocytes, and surprisingly, higher levels of astrocyte markers compared to astrocytes chronically cultured in FBS. In contrast, astrocyte and inflammatory markers in serum-free astrocytes were upregulated 24 h after either acute 2% FBS or cytokine exposure, confirming their capacity to become reactive. Importantly, this suggests that distinct signaling pathways are involved in acute and chronic astrocyte reactivity. Despite having a similar morphology, chronically serum-cultured astrocyte-derived EVs (ADEVs) were smaller in size compared to serum-free ADEVs and could reactivate serum-free astrocytes. Proteomic analysis identified distinct protein datasets for both types of ADEVs with enrichment of complement and coagulation cascades for chronically serum-cultured astrocyte-derived EVs, offering insights into their roles in the CNS. Collectively, these results suggest that human primary astrocytes cultured in serum-free medium bear similarities with in vivo quiescent astrocytes and the addition of serum induces multiple morphological and transcriptional changes that are specific to human reactive astrocytes and their ADEVs. Thus, more emphasis should be made on using multiple structural, molecular, and functional parameters when evaluating ADEVs as biomarkers of astrocyte health.

2.
Braz. J. Pharm. Sci. (Online) ; 60: e23380, 2024. graf
Artigo em Inglês | LILACS | ID: biblio-1533983

RESUMO

Abstract Glioblastoma multiforme is a tumor of the central nervous system. Focal Adhesion Kinase (FAK) and αB-crystalline are two proteins involved in glioblastoma development. In this study, we investigated whether the FAK/αB-crystalline interaction is important for glioblastoma cells, we aimed to investigate the interaction of these two proteins in the glioblastoma multiforme cell line U87-MG. Two peptides named FP01 peptide (derived from αB-crystalline) and FP02 peptide (derived from FAK) were synthesized for this study. Treatment of U87-MG with the peptides FP01 and FP02 in the concentration at 50 µM reduced the viability cellular to around 41% and 51%, respectively. Morphological alterations in the cells treated with the peptides when compared to the control were observed. This study suggests that the interaction between FAK and αB-crystalline is important for the viability of glioblastoma cells


Assuntos
Peptídeos/efeitos adversos , Células/classificação , Glioblastoma/patologia , Proteína-Tirosina Quinases de Adesão Focal/efeitos adversos , Neoplasias/patologia , Linhagem Celular/classificação , Sistema Nervoso Central/anormalidades
3.
J Am Chem Soc ; 145(50): 27459-27470, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38059480

RESUMO

Doping, or incremental substitution of one element for another, is an effective way to tailor a compound's structure as well as its physical and chemical properties. Herein, we replaced up to 30% of Ni with Co in members of the family of layered LiNiB compounds, stabilizing the high-temperature polymorph of LiNiB while the room-temperature polymorph does not form. By studying this layered boride with in situ high-temperature powder diffraction, we obtained a distorted variant of LiNi0.7Co0.3B featuring a perfect interlayer placement of [Ni0.7Co0.3B] layers on top of each other─a structural motif not seen before in other borides. Because of the Co doping, LiNi0.7Co0.3B can undergo a nearly complete topochemical Li deintercalation under ambient conditions, resulting in a metastable boride with the formula Li0.04Ni0.7Co0.3B. Heating of Li0.04Ni0.7Co0.3B in anaerobic conditions led to yet another metastable boride, Li0.01Ni0.7Co0.3B, with a CoB-type crystal structure that cannot be obtained by simple annealing of Ni, Co, and B. No significant alterations of magnetic properties were detected upon Co-doping in the temperature-independent paramagnet LiNi0.7Co0.3B or its Li-deintercalated counterparts. Finally, Li0.01Ni0.7Co0.3B stands out as an exceptional catalyst for the selective hydrogenation of the vinyl C═C bond in 3-nitrostyrene, even in the presence of other competing functional groups. This research showcases an innovative approach to heterogeneous catalyst design by meticulously synthesizing metastable compounds.

4.
Proc Natl Acad Sci U S A ; 120(52): e2310779120, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38113259

RESUMO

We present a comprehensive study of the inhomogeneous mixed-valence compound, EuPd3S4, by electrical transport, X-ray diffraction, time-domain 151Eu synchrotron Mössbauer spectroscopy, and X-ray absorption spectroscopy measurements under high pressure. Electrical transport measurements show that the antiferromagnetic ordering temperature, TN, increases rapidly from 2.8 K at ambient pressure to 23.5 K at ~19 GPa and plateaus between ~19 and ~29 GPa after which no anomaly associated with TN is detected. A pressure-induced first-order structural transition from cubic to tetragonal is observed, with a rather broad coexistence region (~20 GPa to ~30 GPa) that corresponds to the TN plateau. Mössbauer spectroscopy measurements show a clear valence transition from approximately 50:50 Eu2+:Eu3+ to fully Eu3+ at ~28 GPa, consistent with the vanishing of the magnetic order at the same pressure. X-ray absorption data show a transition to a fully trivalent state at a similar pressure. Our results show that pressure first greatly enhances TN, most likely via enhanced hybridization between the Eu 4f states and the conduction band, and then, second, causes a structural phase transition that coincides with the conversion of the europium to a fully trivalent state.

5.
BMC Nephrol ; 24(1): 353, 2023 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-38036951

RESUMO

BACKGROUND: Prolonged hemodialysis (HD) is performed from 6 to 12 h and can last up to 24 h. To prevent system clotting some studies suggest that Regional Citrate Anticoagulation (RCA) use reduces bleeding rates relative to systemic heparin. However, there may be difficulties in the patient's clinical management and completing the prescribed HD with Genius system using RCA. OBJECTIVE: To analyze safety Quality Indicators (IQs) and follow up on prolonged HD with 4% sodium citrate solution in a Genius® hybrid system. METHODS: This is a retrospective cohort conducted in an intensive care unit. RESULTS: 53 random sessions of prolonged HD with 4% sodium citrate solution of critically ill patients with AKI assessed. Evaluated safety indicators were dysnatremia and metabolic alkalosis, observed in 15% and 9.4% of the sessions, respectively. Indicators of effectiveness were system clotting which occurred in 17.3%, and the minimum completion of the prescribed HD time, which was 75.5%. CONCLUSION: The assessment of the indicators showed that the use of RCA with a 4% sodium citrate solution in prolonged HD with the Genius system in critically ill patients with AKI can be performed in a simple, safe, and effective way.


Assuntos
Injúria Renal Aguda , Ácido Cítrico , Humanos , Injúria Renal Aguda/terapia , Anticoagulantes/uso terapêutico , Citratos/uso terapêutico , Ácido Cítrico/uso terapêutico , Estado Terminal/terapia , Heparina/efeitos adversos , Indicadores de Qualidade em Assistência à Saúde , Diálise Renal , Estudos Retrospectivos , Citrato de Sódio
7.
Arq Bras Cardiol ; 120(2): e20220151, 2023.
Artigo em Inglês, Português | MEDLINE | ID: mdl-36856237

RESUMO

BACKGROUND: Cardiovascular complications of COVID-19 are important aspects of the disease's pathogenesis and prognosis. Evidence on the prognostic role of troponin and myocardial injury in Latin American hospitalized COVID-19 patients is still scarce. OBJECTIVES: To evaluate myocardial injury as independent predictor of in-hospital mortality and invasive mechanical ventilation support in hospitalized patients, from the Brazilian COVID-19 Registry. METHODS: This cohort study is a substudy of the Brazilian COVID-19 Registry, conducted in 31 Brazilian hospitals of 17 cities, March-September 2020. Primary outcomes included in-hospital mortality and invasive mechanical ventilation support. Models for the primary outcomes were estimated by Poisson regression with robust variance, with statistical significance of p<0.05. RESULTS: Of 2,925 patients (median age of 60 years [48-71], 57.1% men), 27.3% presented myocardial injury. The proportion of patients with comorbidities was higher among patients with cardiac injury (median 2 [1-2] vs. 1 [0-2]). Patients with myocardial injury had higher median levels of brain natriuretic peptide, lactate dehydrogenase, creatine phosphokinase, N-terminal pro-brain natriuretic peptide, and C-reactive protein than patients without myocardial injury. As independent predictors, C-reactive protein and platelet counts were related to the risk of death, and neutrophils and platelet counts were related to the risk of invasive mechanical ventilation support. Patients with high troponin levels presented a higher risk of death (RR 2.03, 95% CI 1.60-2.58) and invasive mechanical ventilation support (RR 1.87, 95% CI 1.57-2.23), when compared to those with normal troponin levels. CONCLUSION: Cardiac injury was an independent predictor of in-hospital mortality and the need for invasive mechanical ventilation support in hospitalized COVID-19 patients.


FUNDAMENTO: As complicações cardiovasculares da COVID-19 são aspectos importantes da patogênese e do prognóstico da doença. Evidências do papel prognóstico da troponina e da lesão miocárdica em pacientes hospitalizados com COVID-19 na América Latina são ainda escassos. OBJETIVOS: Avaliar a lesão miocárdica como preditor independente de mortalidade hospitalar e suporte ventilatório mecânico em pacientes hospitalizados, do registro brasileiro de COVID-19. MÉTODOS: Este estudo coorte é um subestudo do registro brasileiro de COVID-19, conduzido em 31 hospitais brasileiros de 17 cidades, de março a setembro de 2020. Os desfechos primários incluíram mortalidade hospitalar e suporte ventilatório mecânico invasivo. Os modelos para os desfechos primários foram estimados por regressão de Poisson com variância robusta, com significância estatística de p<0,05. RESULTADOS: Dos 2925 pacientes [idade mediana de 60 anos (48-71), 57,1%], 27,3% apresentaram lesão miocárdica. A proporção de pacientes com comorbidades foi maior nos pacientes com lesão miocárdica [mediana 2 (1-2) vs. 1 (0-20)]. Os pacientes com lesão miocárdica apresentaram maiores valores medianos de peptídeo natriurético cerebral, lactato desidrogenase, creatina fosfoquinase, N-terminal do pró-peptídeo natriurético tipo B e proteína C reativa em comparação a pacientes sem lesão miocárdica. Como fatores independentes, proteína C reativa e contagem de plaquetas foram relacionados com o risco de morte, e neutrófilos e contagem de plaquetas foram relacionados ao risco de suporte ventilatório mecânico invasivo. Os pacientes com níveis elevados de troponina apresentaram um maior risco de morte (RR 2,03, IC95% 1,60-2,58) e suporte ventilatório mecânico (RR 1,87;IC95% 1,57-2,23), em comparação àqueles com níveis de troponina normais. CONCLUSÃO: Lesão cardíaca foi um preditor independente de mortalidade hospitalar e necessidade de suporte ventilatório mecânico em pacientes hospitalizados com COVID-19.


Assuntos
COVID-19 , Traumatismos Cardíacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Brasil/epidemiologia , Proteína C-Reativa , Estudos de Coortes , Prognóstico , Idoso
8.
Artigo em Inglês | LILACS | ID: biblio-1422693

RESUMO

Abstract Objectives: to evaluate the use of iron supplementation and associated factors in children aged six to 59 months attended at the Family Health Strategy units in a city in Minas Gerais (MG). Methods: a cross-sectional, analytical-exploratory study, carried out with 252 children aged six to 59 months, attended at ten units, between 2014 and 2016. A structured questionnaire was used to collect data on socioeconomic conditions, maternal health, child's health and the knowledge of those responsible regarding anemia and iron supplementation, in addition to analysis of the child's medical records /booklet to collect test results. Descriptive statistics, bivariate association analysis and logistic regression for multivariate analysis were performed. Results: only 22.6% of the children aged between six and 24 months were receiving iron supplement at the time of the interview. Considering children aged six to 59 months, 13.1% were supplemented and breastfeeding time (p=0.006) and the participation in childcare (p=0.042), were positively associated with the use of supplementation. Conclusion: most children aged six to 24 months were not receiving supplementation as recommended by the Ministry of Health, demonstrating the need to implement prevention programs, such as the National Iron Supplementation Program and training of professionals on the importance of health education in preventing childhood anemia.


Resumo Objetivos: avaliar o uso do suplemento de ferro e fatores associados em crianças de seis a 59 meses atendidas em unidades Estratégia Saúde da Família em município de Minas Gerais (MG). Métodos: estudo transversal, analítico-exploratório, realizado com 252 crianças na faixa etária seis a 59 meses, atendidas em dez unidades, entre 2014 e 2016. Utilizou-se questionário estruturado para coleta de dados sobre condições socioeconômicas, saúde materna, saúde da criança e conhecimentos dos responsáveis acerca da anemia e suplementação com ferro, além de análise do prontuário / caderneta da criança para coleta de resultados de exames. Realizou-se análise estatística descritiva, análise de associação bivariada e regressão logística para análise multivariada. Resultados: apenas 22,6% das crianças com idade entre seis e 24 meses estavam recebendo o suplemento de ferro no momento da entrevista. Considerando as crianças de seis a 59 meses, 13,1% eram suplementadas e o tempo de amamentação (p=0,006) e a participação na puericultura (p=0,042) apresentaram associação com o uso de suplemento. Conclusão: a maioria das crianças de seis a 24 meses não recebia a suplementação, demonstrando a necessidade de implementação dos programas de prevenção, como o Programa Nacional de Suplementação de Ferro e capacitação dos profissionais sobre a importância da educação em saúde para prevenção da anemia infantil.


Assuntos
Humanos , Recém-Nascido , Lactente , Pré-Escolar , Cuidado da Criança , Anemia Ferropriva/prevenção & controle , Suplementos Nutricionais , Deficiências de Ferro , Ferro/uso terapêutico , Serviços Preventivos de Saúde , Estratégias de Saúde Nacionais , Brasil , Estudos Transversais
9.
Braz. J. Pharm. Sci. (Online) ; 59: e23075, 2023. graf
Artigo em Inglês | LILACS | ID: biblio-1505836

RESUMO

Abstract Focal Adhesion Kinase (FAK) protein participates in proliferation, migration, cell survival, and apoptosis process. It has been described as overexpressed in several neoplasms being a promising target for therapy. BCR-ABL negative chronic Myeloproliferative Neoplasms (MPN) are clonal disorders characterized by the excess of proliferation and apoptosis resistance. The identification of the acquired JAK2 V617F mutation in MPN patients allowed a better understanding of pathogenesis. However, there is still no pharmacological treatment that leads all patients to molecular remission, justifying new studies. The present study aimed to evaluate FAK involvement in the viability and apoptosis of HEL and SET-2 cells, both JAK2 V617F positive cell lines. The FAK inhibitor PF 562,271 was used. Cell viability was determined using MTT assay and apoptosis verified by cleaved PARP, cleaved Caspase 3 and Annexin-V/PI staining detection. FAK inhibition significantly reduced HEL and SET-2 cells viability and induced apoptosis. Considering the role of JAK/STAT pathway in MPN, further investigation of FAK participation in the MPN cells proliferation and apoptosis resistance, as well as possible crosstalk between JAK and FAK and downstream pathways may contribute to the knowledge of MPN pathophysiology, the discovery of new molecular targets, and JAK inhibitors resistance mechanisms.


Assuntos
Apoptose , Proteína-Tirosina Quinases de Adesão Focal/análise , Janus Quinase 2/efeitos adversos , Pacientes/classificação , Linhagem Celular/classificação , Neoplasias/patologia
10.
Arq. bras. cardiol ; 120(2): e20220151, 2023. tab, graf
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1420188

RESUMO

Resumo Fundamento As complicações cardiovasculares da COVID-19 são aspectos importantes da patogênese e do prognóstico da doença. Evidências do papel prognóstico da troponina e da lesão miocárdica em pacientes hospitalizados com COVID-19 na América Latina são ainda escassos. Objetivos Avaliar a lesão miocárdica como preditor independente de mortalidade hospitalar e suporte ventilatório mecânico em pacientes hospitalizados, do registro brasileiro de COVID-19. Métodos Este estudo coorte é um subestudo do registro brasileiro de COVID-19, conduzido em 31 hospitais brasileiros de 17 cidades, de março a setembro de 2020. Os desfechos primários incluíram mortalidade hospitalar e suporte ventilatório mecânico invasivo. Os modelos para os desfechos primários foram estimados por regressão de Poisson com variância robusta, com significância estatística de p<0,05. Resultados Dos 2925 pacientes [idade mediana de 60 anos (48-71), 57,1%], 27,3% apresentaram lesão miocárdica. A proporção de pacientes com comorbidades foi maior nos pacientes com lesão miocárdica [mediana 2 (1-2) vs. 1 (0-20)]. Os pacientes com lesão miocárdica apresentaram maiores valores medianos de peptídeo natriurético cerebral, lactato desidrogenase, creatina fosfoquinase, N-terminal do pró-peptídeo natriurético tipo B e proteína C reativa em comparação a pacientes sem lesão miocárdica. Como fatores independentes, proteína C reativa e contagem de plaquetas foram relacionados com o risco de morte, e neutrófilos e contagem de plaquetas foram relacionados ao risco de suporte ventilatório mecânico invasivo. Os pacientes com níveis elevados de troponina apresentaram um maior risco de morte (RR 2,03, IC95% 1,60-2,58) e suporte ventilatório mecânico (RR 1,87;IC95% 1,57-2,23), em comparação àqueles com níveis de troponina normais. Conclusão Lesão cardíaca foi um preditor independente de mortalidade hospitalar e necessidade de suporte ventilatório mecânico em pacientes hospitalizados com COVID-19.


Abstract Background Cardiovascular complications of COVID-19 are important aspects of the disease's pathogenesis and prognosis. Evidence on the prognostic role of troponin and myocardial injury in Latin American hospitalized COVID-19 patients is still scarce. Objectives To evaluate myocardial injury as independent predictor of in-hospital mortality and invasive mechanical ventilation support in hospitalized patients, from the Brazilian COVID-19 Registry. Methods This cohort study is a substudy of the Brazilian COVID-19 Registry, conducted in 31 Brazilian hospitals of 17 cities, March-September 2020. Primary outcomes included in-hospital mortality and invasive mechanical ventilation support. Models for the primary outcomes were estimated by Poisson regression with robust variance, with statistical significance of p<0.05. Results Of 2,925 patients (median age of 60 years [48-71], 57.1% men), 27.3% presented myocardial injury. The proportion of patients with comorbidities was higher among patients with cardiac injury (median 2 [1-2] vs. 1 [0-2]). Patients with myocardial injury had higher median levels of brain natriuretic peptide, lactate dehydrogenase, creatine phosphokinase, N-terminal pro-brain natriuretic peptide, and C-reactive protein than patients without myocardial injury. As independent predictors, C-reactive protein and platelet counts were related to the risk of death, and neutrophils and platelet counts were related to the risk of invasive mechanical ventilation support. Patients with high troponin levels presented a higher risk of death (RR 2.03, 95% CI 1.60-2.58) and invasive mechanical ventilation support (RR 1.87, 95% CI 1.57-2.23), when compared to those with normal troponin levels. Conclusion Cardiac injury was an independent predictor of in-hospital mortality and the need for invasive mechanical ventilation support in hospitalized COVID-19 patients.

11.
ACS Mater Au ; 2(5): 614-625, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36124003

RESUMO

Achieving kinetic control to synthesize metastable compounds is a challenging task, especially in solid-state reactions where the diffusion is slow. Another challenge is the unambiguous crystal structure determination for metastable compounds when high-quality single crystals suitable for single-crystal X-ray diffraction are inaccessible. In this work, we report an unconventional means of synthesis and an effective strategy to solve the crystal structure of an unprecedented metastable compound LiNi12B8. This compound can only be produced upon heating a metastable layered boride, HT-Li0.4NiB (HT: high temperature), in a sealed niobium container. A conventional heating and annealing of elements do not yield the title compound, which is consistent with the metastable nature of LiNi12B8. The process to crystallize this compound is sensitive to the annealing temperature and dwelling time, a testament to the complex kinetics involved in the formation of the product. The unavailability of crystals suitable for single-crystal X-ray diffraction experiments prompted solving the crystal structure from high-resolution synchrotron powder X-ray diffraction data. This compound crystallizes in a new structure type with space group I4/mmm (a = 10.55673(9) Å, c = 10.00982(8) Å, V = 1115.54(3) Å3, Z = 6). The resulting complex crystal structure of LiNi12B8 is confirmed by scanning transmission electron microscopy and solid-state 11B and 7Li NMR spectroscopy analyses. The extended Ni framework with Li/Ni disorder in its crystal structure resulted in the spin-glass or cluster glass type magnetic ordering below 24 K. This report illustrates a "contemporary twist" to traditional methodologies toward synthesizing a metastable compound and provides a recipe for solving structures by combining the complementary characterization techniques in the cases where the traditionally used single-crystal X-ray diffraction method is nonapplicable.

12.
Neurochem Int ; 159: 105403, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35853553

RESUMO

Alzheimer's disease has been considered mostly as a neuronal pathology, although increasing evidence suggests that glial cells might play a key role in the disease onset and progression. In this sense, astrocytes, with their central role in neuronal metabolism and function, are of great interest for increasing our understanding of the disease. Thus, exploring the morphological and functional changes suffered by astrocytes along the course of this disorder has great therapeutic and diagnostic potential. In this work we isolated and cultivated astrocytes from symptomatic 9-10-months-old adult 3xTg-AD mice, with the aim of characterizing their phenotype and exploring their pathogenic potential. These "old" astrocytes occurring in the 3xTg-AD mouse model of Alzheimer's Disease presented high proliferation rate and differential expression of astrocytic markers compared with controls. They were neurotoxic to primary neuronal cultures both, in neuronal-astrocyte co-cultures and when their conditioned media (ACM) was added into neuronal cultures. ACM caused neuronal GSK3ß activation, changes in cytochrome c pattern, and increased caspase 3 activity, suggesting intrinsic apoptotic pathway activation. Exposure of neurons to ACM caused different subcellular responses. ACM application to the somato-dendritic domain in compartmentalised microfluidic chambers caused degeneration both locally in soma/dendrites and distally in axons. However, exposure of axons to ACM did not affect somato-dendritic nor axonal integrity. We propose that this newly described old 3xTg-AD neurotoxic astrocytic population can contribute towards the mechanistic understanding of the disease and shed light on new therapeutical opportunities.


Assuntos
Doença de Alzheimer , Síndromes Neurotóxicas , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Astrócitos/metabolismo , Modelos Animais de Doenças , Camundongos , Camundongos Transgênicos , Neurônios/metabolismo , Síndromes Neurotóxicas/metabolismo
13.
Artigo em Inglês | MEDLINE | ID: mdl-35657126

RESUMO

Objective: To assess caregivers' perception about the changes in the daily habits of children and adolescents with type 1 diabetes during the COVID-19 pandemic. Subjects and methods: Primary caregivers of youth aged ≤18 with or without type 1 diabetes were selected for the diabetes and the control groups. Caregivers estimated the youth's time (hours) of physical activity and screen time before and during the pandemic, and rated the quality of eating habits and medication adherence from 0 to 10. The primary outcome was the change in physical activity time, screen time, and eating habits scores during isolation. Between-group analyses and within-group comparisons were conducted. A post hoc analysis was performed using logistic regression to correct for confounding factors. Results: In total, 764 participants were included (381 diabetes group vs. 383 control group). Before the pandemic, the diabetes group presented a reduced median of physical activity (P < 0.001) and screen time (P < 0.001). During the pandemic, the difference between both groups remained similar (P = 0.58). Scores of quality of eating habits were similar in both groups before the pandemic [8.0 (7.0-9.0) vs. 8.0 (7.0-9.0), P = 0.31] but decreased during the pandemic [7.0 (5.1-8.1) vs. 8.0 (6.0-9.0), P < 0.001]. The diabetes group had a significantly worse change in eating habits scores (P < 0.01). Conclusion: During the pandemic, eating habits were significantly worse in youth with diabetes than in those without diabetes.

14.
Arch. endocrinol. metab. (Online) ; 66(3): 345-354, June 2022. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1393848

RESUMO

ABSTRACT Objective: To assess caregivers' perception about the changes in the daily habits of children and adolescents with type 1 diabetes during the COVID-19 pandemic. Subjects and methods: Primary caregivers of youth aged ≤18 with or without type 1 diabetes were selected for the diabetes and the control groups. Caregivers estimated the youth's time (hours) of physical activity and screen time before and during the pandemic, and rated the quality of eating habits and medication adherence from 0 to 10. The primary outcome was the change in physical activity time, screen time, and eating habits scores during isolation. Between-group analyses and within-group comparisons were conducted. A post hoc analysis was performed using logistic regression to correct for confounding factors. Results: In total, 764 participants were included (381 diabetes group vs. 383 control group). Before the pandemic, the diabetes group presented a reduced median of physical activity (P < 0.001) and screen time (P < 0.001). During the pandemic, the difference between both groups remained similar (P = 0.58). Scores of quality of eating habits were similar in both groups before the pandemic [8.0 (7.0-9.0) vs. 8.0 (7.0-9.0), P = 0.31] but decreased during the pandemic [7.0 (5.1-8.1) vs. 8.0 (6.0-9.0), P < 0.001]. The diabetes group had a significantly worse change in eating habits scores (P < 0.01). Conclusion: During the pandemic, eating habits were significantly worse in youth with diabetes than in those without diabetes.

15.
Inorg Chem ; 61(16): 6160-6174, 2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35412816

RESUMO

A set of three Cr-dimer compounds, Cr2Q2(en)4X2 (Q: S, Se; X: Br, Cl; en: ethylenediamine), with monoatomic chalcogenide bridges have been synthesized via a single-step solvothermal route. Chalcogenide linkers mediate magnetic exchange between Cr3+ centers, while bidentate ethylenediamine ligands complete the distorted octahedral coordination of Cr centers. Unlike the compounds previously reported, none of the chalcogenide atoms are connected to extra ligands. Magnetic susceptibility studies indicate antiferromagnetic coupling between Cr3+ centers, which are moderate in Cr2Se2(en)4X2 and stronger in Cr2S2(en)4Cl2. Fitting the magnetic data requires a biquadratic exchange term. High-frequency EPR spectra showing characteristic signals due to coupled S = 1 spin states could be interpreted in terms of the "giant spin" Hamiltonian. A fourth compound, Cr2Se8(en)4, has a single diatomic Se bridge connecting the two Cr3+ centers and shows weak ferromagnetic exchange interactions. This work demonstrates the tunability in strength and type of exchange interactions between metal centers by manipulating the interatomic distances and number of bridging chalcogenide linkers.

16.
Fisioter. Pesqui. (Online) ; 29(1): 22-28, jan.-mar. 2022. tab, graf
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1375474

RESUMO

RESUMO Indivíduos acometidos pelo acidente vascular encefálico (AVE) se beneficiam de diferentes estratégias terapêuticas que apresentam comprovação da eficácia por meio da condução de ensaios clínicos aleatorizados (ECA) bem delineados. Compreender as etapas do estudo pode auxiliar os pesquisadores na realização de futuros ensaios clínicos. Dessa forma, o objetivo deste estudo foi descrever o processo de recrutamento, retenção, presença e adesão na condução de um ECA realizado com indivíduos pós-AVE na fase crônica na cidade de Belo Horizonte (MG), Brasil, com o propósito de investigar a eficácia do treino específico da tarefa para membros superiores e inferiores na melhora do nível de atividade física e mobilidade. Nos resultados, foi observado que dos 674 potenciais participantes, não foi possível contatar 240; 384 não foram avaliados por não atenderem aos critérios de elegibilidade. Participaram da avaliação presencial 50 indivíduos e 14 não fizeram parte do estudo pelo mesmo motivo. Apenas 36 indivíduos iniciaram as intervenções (taxa de recrutamento de 5,3%). Uma taxa de retenção de 80,6% foi observada. Sete indivíduos abandonaram o estudo, principalmente por desinteresse pelas atividades. A taxa de presença foi de 80,9%, e o principal motivo para ausência nas sessões foi incompatibilidade de horário com as consultas médicas. A taxa de adesão foi de 82,7%, com 180 interrupções durante as sessões, sendo sair mais cedo o motivo mais comum. Esses resultados indicam algumas dificuldades no processo de condução do ECA com indivíduos na fase crônica do AVE envolvendo treino específico da tarefa. Apesar dessas dificuldades, a intervenção proposta pode ser considerada viável.


RESUMEN Las personas afectadas por accidente cerebrovascular (ACV) tienen a su disposición diferentes estrategias terapéuticas que muestran evidencia de eficacia a través de la realización de ensayos clínicos aleatorizados (ECA) bien diseñados. Conocer las etapas del estudio puede ayudar a los investigadores a realizar futuros ensayos clínicos. Así, el objetivo de este estudio fue describir el proceso de selección, retención, asistencia y adherencia de un ECA realizado con individuos post-ACV en fase crónica en la ciudad de Belo Horizonte (Brasil), para investigar la efectividad del entrenamiento específico de tareas para las extremidades superiores e inferiores en la mejora del nivel de actividad física y la movilidad. En los resultados se observó que, de los 674 potenciales participantes, no fue posible contactar a 240; y 384 no fueron evaluados por no cumplir con los criterios de elegibilidad. Cincuenta personas participaron en la evaluación presencial y 14 no formaron parte del estudio por la misma razón. Solo 36 personas empezaron las intervenciones (tasa de selección del 5,3%). Se observó una tasa de retención del 80,6%. Siete personas abandonaron el estudio, principalmente por falta de interés en las actividades. La tasa de asistencia fue del 80,9%, y el principal motivo de ausencia a las sesiones fue la incompatibilidad de horario con las citas médicas. La tasa de adherencia fue del 82,7%, con 180 interrupciones durante las sesiones, y la salida anticipada fue la razón más frecuente. Los resultados apuntan algunas dificultades en el proceso de realización del ECA con individuos en fase crónica del ACV con relación al entrenamiento específico de tarea. A pesar de esto, la intervención propuesta puede considerarse viable.


ABSTRACT Individuals who suffered stroke benefit from different therapeutic strategies whose efficacy has been proved by well-designed randomized controlled trials (RCTs). Understanding study steps may assist researchers in conducting future RCTs. Thus, the objective of this study was to describe the process of recruitment, retention, attendance, and adherence in conducting RCTs with individuals in the chronic phase of stroke in the municipality of Belo Horizonte/MG/Brazil, with the purpose of investigating the efficacy of specific task training for both lower and upper limbs in improving patients' physical activity and mobility. Results showed that, of the 674 potential participants, it was impossible to contact 240 individuals and 384 were excluded from our sample for failing to meet eligibility criteria. In total, 50 individuals participated in clinical evaluations and 14 were excluded from the study for the same reason. Overall, 36 individuals started the interventions, a 5.3% recruitment rate. An 80.6% retention rate was observed. In total, seven individuals left the study, mainly due to lack of interest in the activities. We found an 80.9% attendance rate, and the main reason for missing medical appointments was incompatibility with treatment schedule. We also observed an 82.7% adherence rate. Of these, 180 interrupted sessions were mainly due to patients leaving early. These results indicate some difficulties found in conducting RCTs with individuals in the chronic phase of stroke, especially regarding specific task training. Despite these difficulties, the proposed intervention can be considered feasible.

17.
Hypertens Pregnancy ; 41(1): 15-22, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34812111

RESUMO

To evaluate total Th1/Th2 cytokines in CD3+ cells (immunocompetent T-lymphocytes) and peripheral blood lymphocytes, mostly CD4+ (T helper cells) and CD8+ (T-cytotoxic cells) subpopulations in preeclampsia. Total blood leukocytes and lymphocytes counts, percent cells: CD3+, INF-g+/CD3+, IL-4+/CD3+, and IL-10+/CD3+, CD4+/CD8+ were determined by flow-cytometry. Preeclampsia (n= 26) and normal pregnancy (n= 25) participants were age and gestational age matched. CD4+ lymphocytes count was higher in preeclampsia, compared with normal pregnancy (43.6 ± 5.8 vs 37.6 ± 5.6%; P< 0.001). CD3+ cells Th1/Th2 shift was not detected in preeclampsia, yet may be present in other cell types, such as CD4+ and CD3 - lymphocytes.


Assuntos
Citocinas , Pré-Eclâmpsia , Feminino , Humanos , Gravidez , Linfócitos T Auxiliares-Indutores , Células Th1 , Células Th2
18.
RNA Biol ; 18(sup2): 832-855, 2021 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-34882524

RESUMO

Neurons have highlighted the needs for decentralized gene expression and specific RNA function in somato-dendritic and axonal compartments, as well as in intercellular communication via extracellular vesicles (EVs). Despite advances in miRNA biology, the identity and regulatory capacity of other small non-coding RNAs (sncRNAs) in neuronal models and local subdomains has been largely unexplored.We identified a highly complex and differentially localized content of sncRNAs in axons and EVs during early neuronal development of cortical primary neurons and in adult axons invivo. This content goes far beyond miRNAs and includes most known sncRNAs and precisely processed fragments from tRNAs, sno/snRNAs, Y RNAs and vtRNAs. Although miRNAs are the major sncRNA biotype in whole-cell samples, their relative abundance is significantly decreased in axons and neuronal EVs, where specific tRNA fragments (tRFs and tRHs/tiRNAs) mainly derived from tRNAs Gly-GCC, Val-CAC and Val-AAC predominate. Notably, although 5'-tRHs compose the great majority of tRNA-derived fragments observed invitro, a shift to 3'-tRNAs is observed in mature axons invivo.The existence of these complex sncRNA populations that are specific to distinct neuronal subdomains and selectively incorporated into EVs, equip neurons with key molecular tools for spatiotemporal functional control and cell-to-cell communication.


Assuntos
Axônios/metabolismo , Comunicação Celular , Vesículas Extracelulares/metabolismo , Neurônios/metabolismo , Pequeno RNA não Traduzido/genética , Pequeno RNA não Traduzido/metabolismo , Transporte Biológico , Fracionamento Celular/métodos , Biologia Computacional/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Anotação de Sequência Molecular , Crescimento Neuronal , Conformação de Ácido Nucleico , Pequeno RNA não Traduzido/química , RNA de Transferência/química , RNA de Transferência/genética , RNA de Transferência/metabolismo , Frações Subcelulares
19.
Artigo em Inglês | MEDLINE | ID: mdl-34886080

RESUMO

Background: Vascular access surveillance of dialysis patients is a challenging task for clinicians. We derived and validated an arteriovenous fistula failure model (AVF-FM) based on machine learning. Methods: The AVF-FM is an XG-Boost algorithm aimed at predicting AVF failure within three months among in-centre dialysis patients. The model was trained in the derivation set (70% of initial cohort) by exploiting the information routinely collected in the Nephrocare European Clinical Database (EuCliD®). Model performance was tested by concordance statistic and calibration charts in the remaining 30% of records. Features importance was computed using the SHAP method. Results: We included 13,369 patients, overall. The Area Under the ROC Curve (AUC-ROC) of AVF-FM was 0.80 (95% CI 0.79-0.81). Model calibration showed excellent representation of observed failure risk. Variables associated with the greatest impact on risk estimates were previous history of AVF complications, followed by access recirculation and other functional parameters including metrics describing temporal pattern of dialysis dose, blood flow, dynamic venous and arterial pressures. Conclusions: The AVF-FM achieved good discrimination and calibration properties by combining routinely collected clinical and sensor data that require no additional effort by healthcare staff. Therefore, it can potentially enable risk-based personalization of AVF surveillance strategies.


Assuntos
Fístula Arteriovenosa , Derivação Arteriovenosa Cirúrgica , Falência Renal Crônica , Humanos , Aprendizado de Máquina , Diálise Renal
20.
Inorg Chem ; 60(24): 19345-19355, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34889600

RESUMO

Canfieldite, Ag8SnS6, is a semiconducting mineral notable for its high ionic conductivity, photosensitivity, and low thermal conductivity. We report the solution growth of large single crystals of Ag8SnS6 of mass up to 1 g from a ternary Ag-Sn-S melt. On cooling from high temperature, Ag8SnS6 undergoes a known cubic (F4̅3m) to orthorhombic (Pna21) phase transition at ≈460 K. By studying the magnetization and thermal expansion between 5-300 K, we discover a second structural transition at ≈120 K. Single crystal X-ray diffraction reveals the low-temperature phase adopts a different orthorhombic structure with space group Pmn21 (a = 7.662 9(5) Å, b = 7.539 6(5) Å, c = 10.630 0(5) Å, Z = 2 at 90 K) that is isostructural to the room-temperature forms of the related Se-based compounds Ag8SnSe6 and Ag8GeSe6. The 120 K transition is first-order and has a large thermal hysteresis. On the basis of the magnetization and thermal expansion data, the room-temperature polymorph can be kinetically arrested into a metastable state by rapidly cooling to temperatures below 40 K. We last compare the room- and low-temperature forms of Ag8SnS6 with its argyrodite analogues, Ag8TQ6 (T = Si, Ge, Sn; Q = S, Se), and identify a trend relating the preferred structures to the unit cell volume, suggesting smaller phase volume favors the Pna21 arrangement. We support this picture by showing that the transition to the Pmn21 phase is avoided in Ge alloyed Ag8Sn1-xGexS6 samples as well as in pure Ag8GeS6.

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