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1.
Braz J Cardiovasc Surg ; 38(3): 398-404, 2023 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-36592074

RESUMO

INTRODUCTION: Congenital heart diseases (CHDs) constitute the most prevalent congenital pathology, and they are a consequence of structural and functional abnormalities during fetal development. The etiology of CHD involves the interaction of genetic and environmental factors. Fetal cardiac surgery aims at preventing natural pathways of CHD in utero, mitigating progression to more complex abnormalities. The goal of this review was to demonstrate the benefits and risks of fetal interventions in the two most prevalent CHDs, pulmonary stenosis and pulmonary atresia with an intact ventricular septum, but also critical aortic stenosis and hypoplastic left heart syndrome. METHODS: Original and relevant articles were selected by meta-aggregation to perform a qualitative analysis of fetal cardiac interventions for pulmonary stenosis and critical aortic stenosis. The Joanna Briggs Institute's Qualitative Assessment and Review Instrument (or JBI-QARI) was used for data quality appraisal. RESULTS: Of 61 potential articles, 13 were selected, and nine were finally included. Discussion: The present review demonstrated that fetal cardiac surgery increases right ventricular growth and hemodynamic flow in pulmonary stenosis, whereas in critical aortic stenosis it enables growth of the left ventricle and increases left ventricular pressure. However, it has a high complication rate, along with considerable morbidity and mortality. CONCLUSION: The benefits of fetal cardiac surgery for pulmonary stenosis and critical aortic stenosis are well-described in the literature; however, there is a significant risk of complications which can be reduced by the surgeon's technical expertise and well-structured hospital facilities.


Assuntos
Estenose da Valva Aórtica , Cardiopatias Congênitas , Atresia Pulmonar , Estenose da Valva Pulmonar , Humanos , Cardiopatias Congênitas/cirurgia , Atresia Pulmonar/cirurgia , Estenose da Valva Aórtica/cirurgia , Estenose da Valva Pulmonar/cirurgia , Medição de Risco
2.
Clinics ; 78: 100311, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1528420

RESUMO

Abstract Objective Gastroschisis (GS) is a congenital anomaly in the abdominal wall with the intestinal loops exiting laterally to the umbilicus. The contact of the loops with Amniotic Fluid (AF) causes an inflammatory process in the exposed part, leading to an extended hospital stay and an increased risk of morbidity due to alterations related to intestinal motility. The authors aimed to evaluate the time of exposure to the AF in the experimental GS and to search for potential biomarkers of intestinal inflammation by measuring microRNAs. Methods Rat fetuses were divided into three groups: a) CONTROL, b) GS reared on day 18 (GS = 18), and c) GS reared on day 19.5 (GS = 19) (term = 22 days). On day 21.5, the fetuses were removed for biometric parameters and biochemical analyses: 1) Biometrics: Body and Intestinal Weight (BW, IW), and intestinal-body weight ratio (IW/BW); 2) Descriptive histopathology and 3) miR-143 quantification by real-time Polymerase Chain Reaction (PCR). Results BW was higher in CONTROL than GS 18 and G19 (p < 0.05). IW, IW/BW, intestinal water, and mRNA-143 were higher in GS 18 and GS 19 than in CONTROL, and GS 18 was higher than GS 19 (p < 0.05). The average of the inflammation score from the intestinal wall with mucosal inflammation and intra-epithelial lymphocytes shows worst in GS 18 and GS 19 vs. CONTROL (p < 0.05). Conclusions The tissue expression of mRNA-143 and the morphological changes in the intestine of GS worsened according to the time of exposure to AF, which could be a possible marker of fetal intestinal damage.

3.
Rev. enferm. UFSM ; 13: 26, 2023.
Artigo em Inglês, Espanhol, Português | LILACS, BDENF - Enfermagem | ID: biblio-1444577

RESUMO

Objetivo: verificar a prevalência dos principais eventos vasculares associados a pacientes com COVID-19 admitidos em um hospital público do Recife. Método: trata-se de um estudo transversal descritivo, realizado por meio das bases de dados epidemiológicos e prontuários eletrônicos de pacientes, no período de março de 2020 a agosto de 2021. Resultados: analisaram-se 1122 pacientes, (58,8%) com diagnóstico positivo para COVID-19. Os principais eventos vasculares evidenciados foram: Tromboembolismo Venoso Profundo (4,55%); Tromboembolismo Pulmonar (2,5%); Oclusão Arterial Aguda (0,98%) e Isquemia Crítica de Membro Inferior a mais prevalente, sendo 17,64% dos casos. Conclusão: foi possível apontar a prevalência de eventos vasculares associados a pacientes com COVID-19, admitidos em um hospital público do Recife, tal como classificar os principais eventos vasculares, sua repercussão e evolução. Assim, o conhecimento acerca do perfil desses pacientes no contexto da pandemia pode contribuir para o desenvolvimento de novas pesquisas na área de saúde.


Objective: to verify the prevalence of the main vascular events associated with patients with COVID-19 admitted to a public hospital in Recife. Method: this is a descriptive cross-sectional study, carried out through epidemiological databases and electronic patient records, from March 2020 to August 2021. Results: 1122 patients (58.8%) with a positive diagnosis for COVID-19 were analyzed. The main vascular events evidenced were: Deep Venous Thromboembolism (4.55%); Pulmonary Thromboembolism (2.5%); Acute Arterial Occlusion (0.98%) and Critical Lower Limb Ischemia, the most prevalent, being 17.64% of the cases. Conclusion: it was possible to point out the prevalence of vascular events associated with patients with COVID-19, admitted to a public hospital in Recife, as well as to classify the main vascular events, their repercussion and evolution. Thus, knowledge about the profile of these patients in the context of the pandemic can contribute to the development of new research in the health area.


Objetivo: verificar la prevalencia de los principales eventos vasculares asociados a pacientes con COVID-19 ingresados en un hospital público de Recife. Método: se trata de un estudio descriptivo transversal, realizado a través de bases de datos epidemiológicas y registros electrónicos de pacientes, de marzo de 2020 a agosto de 2021. Resultados: se analizaron 1122 pacientes (58,8%) con diagnóstico positivo para COVID-19. Los principales eventos vasculares evidenciados fueron: Tromboembolismo Venoso Profundo (4,55%); Tromboembolismo Pulmonar (2,5%); Oclusión Arterial Aguda (0,98%) e Isquemia Crítica de Miembros Inferiores el más prevalente, con el 17,64% de los casos. Conclusión: fue posible señalar la prevalencia de eventos vasculares asociados a pacientes con COVID-19, ingresados en un hospital público de Recife, así como clasificar los principales eventos vasculares, sus repercusiones y evolución. Así, el conocimiento del perfil de estos pacientes en el contexto de la pandemia puede contribuir para el desarrollo de nuevas investigaciones en el área de salud.


Assuntos
Humanos , Trombose , Doenças Vasculares , Infecções por Coronavirus , Coagulação Intravascular Disseminada , COVID-19
4.
Rev. bras. cir. cardiovasc ; 38(3): 398-404, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1441203

RESUMO

ABSTRACT Introduction: Congenital heart diseases (CHDs) constitute the most prevalent congenital pathology, and they are a consequence of structural and functional abnormalities during fetal development. The etiology of CHD involves the interaction of genetic and environmental factors. Fetal cardiac surgery aims at preventing natural pathways of CHD in utero, mitigating progression to more complex abnormalities. The goal of this review was to demonstrate the benefits and risks of fetal interventions in the two most prevalent CHDs, pulmonary stenosis and pulmonary atresia with an intact ventricular septum, but also critical aortic stenosis and hypoplastic left heart syndrome. Methods: Original and relevant articles were selected by meta-aggregation to perform a qualitative analysis of fetal cardiac interventions for pulmonary stenosis and critical aortic stenosis. The Joanna Briggs Institute's Qualitative Assessment and Review Instrument (or JBI-QARI) was used for data quality appraisal. Results: Of 61 potential articles, 13 were selected, and nine were finally included. Discussion: The present review demonstrated that fetal cardiac surgery increases right ventricular growth and hemodynamic flow in pulmonary stenosis, whereas in critical aortic stenosis it enables growth of the left ventricle and increases left ventricular pressure. However, it has a high complication rate, along with considerable morbidity and mortality. Conclusion: The benefits of fetal cardiac surgery for pulmonary stenosis and critical aortic stenosis are well-described in the literature; however, there is a significant risk of complications which can be reduced by the surgeon's technical expertise and well-structured hospital facilities.

5.
JACS Au ; 2(3): 631-645, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35373202

RESUMO

The large family of polypeptide GalNAc-transferases (GalNAc-Ts) controls with precision how GalNAc O-glycans are added in the tandem repeat regions of mucins (e.g., MUC1). However, the structural features behind the creation of well-defined and clustered patterns of O-glycans in mucins are poorly understood. In this context, herein, we disclose the full process of MUC1 O-glycosylation by GalNAc-T2/T3/T4 isoforms by NMR spectroscopy assisted by molecular modeling protocols. By using MUC1, with four tandem repeat domains as a substrate, we confirmed the glycosylation preferences of different GalNAc-Ts isoforms and highlighted the importance of the lectin domain in the glycosylation site selection after the addition of the first GalNAc residue. In a glycosylated substrate, with yet multiple acceptor sites, the lectin domain contributes to orientate acceptor sites to the catalytic domain. Our experiments suggest that during this process, neighboring tandem repeats are critical for further glycosylation of acceptor sites by GalNAc-T2/T4 in a lectin-assisted manner. Our studies also show local conformational changes in the peptide backbone during incorporation of GalNAc residues, which might explain GalNAc-T2/T3/T4 fine specificities toward the MUC1 substrate. Interestingly, we postulate that a specific salt-bridge and the inverse γ-turn conformation of the PDTRP sequence in MUC1 are the main structural motifs behind the GalNAc-T4 specificity toward this region. In addition, in-cell analysis shows that the GalNAc-T4 isoform is the only isoform glycosylating the Thr of the immunogenic epitope PDTRP in vivo, which highlights the relevance of GalNAc-T4 in the glycosylation of this epitope. Finally, the NMR methodology established herein can be extended to other glycosyltransferases, such as C1GalT1 and ST6GalNAc-I, to determine the specificity toward complex mucin acceptor substrates.

6.
J Med Chem ; 64(17): 13025-13037, 2021 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-34415167

RESUMO

Human aldehyde oxidase (hAOX1) is mainly present in the liver and has an emerging role in drug metabolism, since it accepts a wide range of molecules as substrates and inhibitors. Herein, we employed an integrative approach by combining NMR, X-ray crystallography, and enzyme inhibition kinetics to understand the inhibition modes of three hAOX1 inhibitors-thioridazine, benzamidine, and raloxifene. These integrative data indicate that thioridazine is a noncompetitive inhibitor, while benzamidine presents a mixed type of inhibition. Additionally, we describe the first crystal structure of hAOX1 in complex with raloxifene. Raloxifene binds tightly at the entrance of the substrate tunnel, stabilizing the flexible entrance gates and elucidating an unusual substrate-dependent mechanism of inhibition with potential impact on drug-drug interactions. This study can be considered as a proof-of-concept for an efficient experimental screening of prospective substrates and inhibitors of hAOX1 relevant in drug discovery.


Assuntos
Aldeído Oxidase/antagonistas & inibidores , Cloridrato de Raloxifeno/farmacologia , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Benzamidinas/química , Benzamidinas/farmacologia , Cristalografia por Raios X , Humanos , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Polimorfismo de Nucleotídeo Único , Ligação Proteica , Conformação Proteica , Cloridrato de Raloxifeno/química , Moduladores Seletivos de Receptor Estrogênico/química , Tioridazina/química , Tioridazina/farmacologia
7.
Chemistry ; 27(29): 7951-7958, 2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-33826192

RESUMO

Interactions of glycan-specific epitopes to human lectin receptors represent novel immune checkpoints for investigating cancer and infection diseases. By employing a multidisciplinary approach that combines isothermal titration calorimetry, NMR spectroscopy, molecular dynamics simulations, and X-ray crystallography, we investigated the molecular determinants that govern the recognition of the tumour and pathogenic glycobiomarker LacdiNAc (GalNAcß1-4GlcNAc, LDN), including their comparison with the ubiquitous LacNAc epitope (Galß1-4GlcNAc, LN), by two human immune-related lectins, galectin-3 (hGal-3) and the macrophage galactose C-type lectin (hMGL). A different mechanism of binding and interactions was observed for the hGal-3/LDN and hMGL/LDN complexes, which explains the remarkable difference in the binding specificity of LDN and LN by these two lectins. The new structural clues reported herein are fundamental for the chemical design of mimetics targeting hGal-3/hMGL recognition process.


Assuntos
Lactose , Neoplasias , Epitopos , Humanos , Lactose/análogos & derivados , Polissacarídeos , Ligação Proteica
8.
Biochemistry ; 60(17): 1327-1336, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33724805

RESUMO

The human macrophage galactose lectin (MGL) is an endocytic type II transmembrane receptor expressed on immature monocyte-derived dendritic cells and activated macrophages and plays a role in modulating the immune system in response to infections and cancer. MGL contains an extracellular calcium-dependent (C-type) carbohydrate recognition domain (CRD) that specifically binds terminal N-acetylgalactosamine glycan residues such as the Tn and sialyl-Tn antigens found on tumor cells, as well as other N- and O-glycans displayed on certain viruses and parasites. Even though the glycan specificity of MGL is known and several binding glycoproteins have been identified, the molecular basis for substrate recognition has remained elusive due to the lack of high-resolution structures. Here we present crystal structures of the MGL CRD at near endosomal pH and in several complexes, which reveal details of the interactions with the natural ligand, GalNAc, the cancer-associated Tn-Ser antigen, and a synthetic GalNAc mimetic ligand. Like the asialoglycoprotein receptor, additional calcium atoms are present and contribute to stabilization of the MGL CRD fold. The structure provides the molecular basis for preferential binding of N-acetylgalactosamine over galactose and prompted the re-evaluation of the binding modes previously proposed in solution. Saturation transfer difference nuclear magnetic resonance data acquired using the MGL CRD and interpreted using the crystal structure indicate a single binding mode for GalNAc in solution. Models of MGL1 and MGL2, the mouse homologues of MGL, explain how these proteins might recognize LewisX and GalNAc, respectively.


Assuntos
Acetilgalactosamina/metabolismo , Antígenos Glicosídicos Associados a Tumores/metabolismo , Lectinas Tipo C/química , Lectinas Tipo C/metabolismo , Animais , Cristalografia por Raios X , Humanos , Ligantes , Camundongos , Ligação Proteica , Domínios Proteicos
9.
Cad. Ibero-Am. Direito Sanit. (Online) ; 10(1): 129-148, jan.-mar.2021.
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1151021

RESUMO

Objetivo: enumerar medidas governativas e de saúde pública implementadas em Portugal decorrentes da pandemia pelo vírus SARS-CoV-2 e descrever a atuação do Gabinete de Segurança do Paciente do Centro Hospitalar Universitário de Lisboa Central (CHULC), referência nacional na resposta à situação de emergência de saúde pública. Métodos: utilizou-se como método a análise normativa, documental, além de relato de caso por pesquisa-ação. Resultados: em Portugal, documentaram-se os primeiros casos de infeção por SARS-CoV-2 a 2 de março de 2020. Os processos assistenciais são geridos pelo Ministério da Saúde e Direção Geral da Saúde, abrangendo o Sistema Nacional de Saúde (universal) e o sector privado. O Gabinete de Segurança do Doente do CHULC, participou na redefinição dos processos, criação de vias alternativas de informação entre as várias estruturas, implementação de inovações no uso de tecnologias e vigilância clínica, gestão dos equipamentos de proteção, motivação e suporte emocional dos profissionais e na consolidação das principais metas de segurança do doente (ex. identificação do doente, medicação e cirurgia segura). A aprendizagem feita com os erros contribui para a melhoria contínua dos processos. Conclusão: em Portugal e no mundo a pandemia por COVID-19 não terminou. Compreendemos que é tempo de refletir e voltar aos princípios básicos da segurança, como a higiene das mãos, a etiqueta respiratória e o controlo ambiental. Na gestão do risco e segurança do paciente em situação de crise, é necessário, mais do que nunca, inovar e aprender com os erros.


Objective: to enumerate governmental and public health measures implemented in Portugal resulting from the SARS-CoV-2 virus pandemic and describe the work of the Patient Safety Office of the Centro Hospitalar Universitário de Lisboa Central (CHULC), a national reference in the response to the situation of public health emergency. Methods: normative, documentary analysis was used as a method, in addition to case reports by action research. Results: in Portugal, the first cases of SARS-CoV-2 infection were documented on March 2, 2020. Assistance processes are managed by the Ministry of Health and the General Directorate of Health, covering the National Health System (universal) and the private sector. The CHULC Patient Safety Office, participated in the redefinition of processes, creation of alternative information routes between the various structures, implementation of innovations in the use of technologies and clinical surveillance, management of protective equipment, motivation and emotional support from professionals and consolidating the main patient safety goals (eg patient identification, medication and safe surgery). Learning from mistakes contributes to the continuous improvement of processes. Conclusion: In Portugal and in the world, the COVID-19 pandemic has not ended. We understand that it is time to reflect and return to the basic principles of safety, such as hand hygiene, respiratory etiquette and environmental control. In the management of risk and safety of patients in crisis situations, it is necessary, more than ever, to innovate and learn from mistakes.


Objetivo: enumerar las medidas gubernamentales y de salud pública implementadas en Portugal como resultado de la pandemia del virus SARS-CoV-2 y describir el trabajo de la Oficina de Seguridad del Paciente del Centro Hospitalar Universitário de Lisboa Central (CHULC), una referencia nacional en la respuesta a la situación de emergencia de salud pública. Métodos: se utilizó como método el análisis documental, normativo, además de los reportes de casos por investigación-acción. Resultados: en Portugal se documentaron los primeros casos de infección por SARS-CoV-2 el 2 de marzo de 2020. Los procesos de atención son gestionados por el Ministerio de Salud y la Dirección General de Salud, abarcando el Sistema Nacional de Salud (universal) y el privado. sector. La Oficina de Seguridad del Paciente del CHULC, participó en la redefinición de procesos, creación de rutas alternativas de información entre las distintas estructuras, implementación de innovaciones en el uso de tecnologías y vigilancia clínica, manejo de equipos de protección, motivación y apoyo emocional de los profesionales y consolidando las principales objetivos de seguridad del paciente (por ejemplo, identificación del paciente, medicación y cirugía segura). Aprender de los errores contribuye a la mejora continua de los procesos. Conclusión: En Portugal y en el mundo, la pandemia de COVID-19 no ha terminado. Entendemos que es hora de reflexionar y volver a los principios básicos de seguridad, como la higiene de manos, la etiqueta respiratoria y el control ambiental. En la gestión del riesgo y la seguridad de los pacientes en situaciones de crisis, es necesario, más que nunca, innovar y aprender de los errores.

10.
Neotrop. ichthyol ; 19(2): e200067, 2021. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1279490

RESUMO

The purpose of this study is to determine the parameters of the reproductive biology of seven commercial species at the Ramsar Site of the Baixada Maranhense to support fisheries management measures. The collections were carried out between 2012 and 2016. The reproductive period, sex ratio, weight-length relationship and first sexual maturity were evaluated for seven species of commercial importance. The sex ratio showed that females are predominant for all species, except for Plagioscion squamossissimus. The weight-length relationship indicated a greater investment in weight for Cichla monoculus and Hassar affinis, and a greater investment in length for Hoplias malabaricus, Plagioscion squamosissimus, Prochilodus lacustris, Pygocentrus nattereri, and Schizodon dissimilis. The reproductive activity of the species was predominant in the rainy season, but C. monoculus, H. malabaricus and P. lacustris showed the ability to reproduce in both seasons. As management measures for the region, it is suggested a change in the closed fishing season established by IBAMA, from December 1 to April 30, to ensure the protection of all commercial species in this study.(AU)


Este estudo teve como objetivo determinar os parâmetros da biologia reprodutiva de sete espécies comerciais no Sítio Ramsar da Baixada Maranhense, para apoiar medidas de manejo pesqueiro. As coletas foram realizadas entre 2012 e 2016, com um ano de coleta para cada espécie. Foram avaliados o período reprodutivo, a razão sexual, a relação peso-comprimento e a primeira maturidade sexual para sete espécies de importância comercial. A razão sexual mostrou que as fêmeas são predominantes para todas as espécies, exceto para Plagioscion squamossissimus. A relação peso-comprimento indicou um maior investimento em peso para Cichla monoculus e Hassar affinis, e um maior investimento em comprimento para Hoplias malabaricus, Plagioscion squamosissimus, Prochilodus lacustris, Pygocentrus nattereri e Schizodon dissimilis. A atividade reprodutiva das espécies foi predominante na estação chuvosa, mas C. monoculus, H. malabaricus e P. lacustris mostraram capacidade de se reproduzir nas duas estações. Como medidas de manejo para a região, sugere-se uma mudança do período de defeso, estabelecida pelo IBAMA, de 1 de dezembro a 30 de abril, para garantir a proteção de todas as espécies comerciais.(AU)


Assuntos
Animais , Reprodução , Maturidade Sexual , Pesqueiros , Peixes/fisiologia , Ecossistema Amazônico
11.
Rev. méd. Minas Gerais ; 31: 31304, 2021.
Artigo em Português | LILACS | ID: biblio-1291415

RESUMO

A problematização dos lugares, papéis e sentidos da Psicologia nos cursos de Medicina é necessária para que as unidades curriculares ligadas a esse campo de conhecimento aportem à formação dos graduandos o desenvolvimento de saberes, habilidades e competências necessários para a o exercício da prática médica humanizada. Este trabalho discute a adoção da Psicologia Humanista de Carl Rogers como fundamento teórico de disciplinas ou módulos ligados à Psicologia na formação médica. Apresenta as bases dessa vertente e relaciona-as à discussão das metodologias de ensino e da relação professor-aluno no ensino médico. Conclui que a teoria analisada pode constituir orientação para a prática docente e as escolhas curriculares e metodológicas da formação médica, apesar dos limites de sua aplicação de forma generalizada nos cursos de graduação. Indica as atividades voltadas para a capacidade dos estudantes de identificar, expressar e refletir sobre seus próprios sentimentos em relação a diferentes situações vivenciadas durante a graduação em Medicina são as mais coerentes com a proposta da psicologia humanista de Carl Rogers.


The problematization of places, roles and meanings of psychology in medical courses is necessary so that the curricular units linked to this field of knowledge contribute to the development of learnings, skills and competences necessary for humanized medical practice. This essay presents the theoretical foundations of Carl Rogers' Humanistic Psychology and advocates its use in the training of future doctors in educational practices consistent with the proposal of Person-Centered Therapy. It concludes that this theory may constitute guidance for theaching practice and curricular choices, despite the limits of general application in medical courses. The activities focused on the student's hability to identifie, express and reflect on their own feelings are the most consistent whit the theoretical foundations of Carl Rogers' Humanistic Psychology.


Assuntos
Humanos , Psicologia Médica/educação , Educação Médica , Relações Médico-Paciente , Educação de Graduação em Medicina , Psicoterapia Centrada na Pessoa
12.
J Med Chem ; 63(20): 11663-11690, 2020 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-32959649

RESUMO

Despite the rapidly increasing number of patients suffering from type 2 diabetes, Alzheimer's disease, and diabetes-induced dementia, there are no disease-modifying therapies that are able to prevent or block disease progress. In this work, we investigate the potential of nature-inspired glucosylpolyphenols against relevant targets, including islet amyloid polypeptide, glucosidases, and cholinesterases. Moreover, with the premise of Fyn kinase as a paradigm-shifting target in Alzheimer's drug discovery, we explore glucosylpolyphenols as blockers of Aß-induced Fyn kinase activation while looking into downstream effects leading to Tau hyperphosphorylation. Several compounds inhibit Aß-induced Fyn kinase activation and decrease pTau levels at 10 µM concentration, particularly the per-O-methylated glucosylacetophloroglucinol and the 4-glucosylcatechol dibenzoate, the latter inhibiting also butyrylcholinesterase and ß-glucosidase. Both compounds are nontoxic with ideal pharmacokinetic properties for further development. This work ultimately highlights the multitarget nature, fine structural tuning capacity, and valuable therapeutic significance of glucosylpolyphenols in the context of these metabolic and neurodegenerative disorders.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Glucosídeos/síntese química , Polifenóis/síntese química , Proteínas Proto-Oncogênicas c-fyn/antagonistas & inibidores , Proteínas tau/metabolismo , Doença de Alzheimer/metabolismo , Permeabilidade da Membrana Celular/efeitos dos fármacos , Colinesterases/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Descoberta de Drogas/métodos , Glucosídeos/química , Glucosídeos/farmacologia , Glicosídeo Hidrolases/antagonistas & inibidores , Células HEK293 , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Estrutura Molecular , Fosforilação , Polifenóis/química , Polifenóis/farmacologia
13.
Exp Physiol ; 105(9): 1571-1578, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32770583

RESUMO

NEW FINDINGS: What is the central question of this study? How do peripheral muscle tissue oxygenation and physical conditioning levels of children and adolescents with cystic fibrosis compare to demographically matched controls? What is the main finding and its importance? Children and adolescents with cystic fibrosis consumed more oxygen, more quickly and exhibited slower recovery, demonstrating that there may have been deficiencies in oxygen supply related to both oxygen uptake and oxygen transport. ABSTRACT: Cystic fibrosis affects skeletal muscle performance and functional capacity. However, it is currently unclear how peripheral muscle behaviour is affected, especially in children and adolescents. To examine this, we compared tissue oxygenation of children and adolescents with cystic fibrosis against healthy volunteers. We also evaluated the functional capacity of participants via the modified shuttle test (MST) and assessed for associations between performance and near-infrared spectroscopy. A total of 124 participants enrolled. Participants were divided into either the cystic fibrosis group (CFG) or the healthy group (HG). Statistical comparisons between groups were evaluated with the Mann-Whitney U test and associations with functional capacity were evaluated using Spearman's correlation coefficient. CFG volunteers scored lower on the MST compared to the HG. They walked shorter distances (P = 0.001) with less efficiency because they performed the tests with a less efficient walking economy (P = 0.001) and a greater deoxyhaemoglobin concentration (P = 0.001). Further, they experienced reduced tissue oxygen saturation (P = 0.037) faster than the HG. As a result, they presented lower respiratory (P = 0.001) and lower heart (P = 0.001) rate values at the end of the MST, with a longer post-test heart rate recovery time (P = 0.005). There was a significant association between deoxygenation time and functional capacity. The CFG consumed more oxygen, more quickly, with a slower recovery, reflecting impairments in the dynamics of muscle oxygen extraction. The results suggest differences in functional capacity and haemodynamic recovery in children and adolescents with cystic fibrosis.


Assuntos
Fibrose Cística/fisiopatologia , Tolerância ao Exercício , Músculo Esquelético/fisiologia , Consumo de Oxigênio , Adolescente , Estudos de Casos e Controles , Criança , Estudos Transversais , Feminino , Frequência Cardíaca , Hemodinâmica , Humanos , Masculino , Desempenho Físico Funcional , Espectroscopia de Luz Próxima ao Infravermelho
14.
Front Chem ; 8: 404, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32457878

RESUMO

Thermally activated delayed fluorescence (TADF) molecules offer nowadays a powerful tool in the development of novel organic light emitting diodes due to their capability of harvesting energy from non-emissive triplet states without using heavy-metal complexes. TADF emitters have very small energy difference between the singlet and triplet excited states, which makes thermally activated reverse intersystem crossing from the triplet states back to the singlet manifold viable. This mechanism generates a long-lived delayed fluorescence component which can be explored in the sensing of oxygen concentration, local temperature, or used in time-gated optical cell-imaging, to suppress interference from autofluorescence and scattering. Despite this strong potential, until recently the application of TADF outside lighting devices has been hindered due to the low biocompatibility, low aqueous solubility and poor performance in polar media shown by the vast majority of TADF emitters. To achieve TADF luminescence in biological media, careful selection or design of emitters is required. Unfortunately, most TADF molecules are not emissive in polar media, thus complexation with biomolecules or the formation of emissive aggregate states is required, in order to retain the delayed fluorescence that is characteristic of these compounds. Herein, we demonstrate a facile method with great generalization potential that maintains the photophysical properties of solvated dyes by combining luminescent molecules with polymeric nanoparticles. Using an established swelling procedure, two known TADF emitters are loaded onto polystyrene nanoparticles to prepare TADF emitting nanomaterials able to be used in live-cell imaging. The obtained particles were characterized by optical spectroscopy and exhibited the desired TADF emission in aqueous media, due to the polymeric matrix shielding the dye from solvent polarity effects. The prepared nanoparticles were incubated with live human cancer cells and showed very low cytotoxicity and good cellular uptake, thus making fluorescence microscopy imaging possible at low dye concentrations.

15.
Chemistry ; 25(61): 13945-13955, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31404475

RESUMO

The human macrophage galactose-type lectin (MGL), expressed on macrophages and dendritic cells (DCs), modulates distinct immune cell responses by recognizing N-acetylgalactosamine (GalNAc) containing structures present on pathogens, self-glycoproteins, and tumor cells. Herein, NMR spectroscopy and molecular dynamics (MD) simulations were used to investigate the structural preferences of MGL against different GalNAc-containing structures derived from the blood group A antigen, the Forssman antigen, and the GM2 glycolipid. NMR spectroscopic analysis of the MGL carbohydrate recognition domain (MGL-CRD, C181-H316) in the absence and presence of methyl α-GalNAc (α-MeGalNAc), a simple monosaccharide, shows that the MGL-CRD is highly dynamic and its structure is strongly altered upon ligand binding. This plasticity of the MGL-CRD structure explains the ability of MGL to accommodate different GalNAc-containing molecules. However, key differences are observed in the recognition process depending on whether the GalNAc is part of the blood group A antigen, the Forssman antigen, or GM2-derived structures. These results are in accordance with molecular dynamics simulations that suggest the existence of a distinct MGL binding mechanism depending on the context of GalNAc moiety presentation. These results afford new perspectives for the rational design of GalNAc modifications that fine tune MGL immune responses in distinct biological contexts, especially in malignancy.


Assuntos
Acetilgalactosamina/química , Lectinas Tipo C/metabolismo , Antígenos de Grupos Sanguíneos/química , Antígenos de Grupos Sanguíneos/metabolismo , Mapeamento de Epitopos , Humanos , Lectinas Tipo C/química , Lectinas Tipo C/genética , Ligantes , Simulação de Dinâmica Molecular , Ressonância Magnética Nuclear Biomolecular , Ligação Proteica , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação
16.
Brachytherapy ; 18(2): 146-153, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30591409

RESUMO

PURPOSE: The purpose of this study was to evaluate clinical response, postrecurrence survival, disease-free survival (DFS), and toxicity related to reirradiation in pelvic recurrence of cervical carcinoma. METHODS AND MATERIALS: A retrospective cohort study of 45 women undergoing high-dose-rate interstitial brachytherapy (HDR-IB) was conducted from 1998 to 2014. Clinical information, as well as data on the malignancy, primary treatment, HDR-IB technique, and toxicity, was collected. Statistical analysis used chi-square or Fisher's exact test, Kaplan-Meier survival curves and log-rank test, and Cox regression, with p < 0.05 for significance. RESULTS: There were 30 cases (67%) of complete clinical response, with a followup period of 9-129 months (20 alive, 10 died). The 5-year postrecurrence survival rate was 52%. Among 15 women without complete clinical response, the survival rate was low (<8 months). In the 30 women with complete clinical response, the 5-year DFS was 42%. All analyzed variables were not associated with survival. Ultrasonography-based needle placement was not associated with disease control or toxicity. Toxicity was reported in 23 women (51%) with 14 fistulas, unrelated to clinical response. However, there was a higher occurrence of fistula when chemotherapy was used. CONCLUSIONS: Reirradiation using HDR-IB for pelvic recurrence of cervical carcinoma yielded a good complete clinical response rate. Postrecurrence survival and DFS rates were higher than expected, equivalent to salvage surgery, but with significant toxicity. Despite toxicity, this technique can be an alternative for selected cases.


Assuntos
Braquiterapia , Carcinoma/radioterapia , Fístula/etiologia , Recidiva Local de Neoplasia/radioterapia , Neoplasias do Colo do Útero/radioterapia , Idoso , Braquiterapia/efeitos adversos , Carcinoma/patologia , Quimiorradioterapia/efeitos adversos , Intervalo Livre de Doença , Feminino , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/tratamento farmacológico , Reirradiação/efeitos adversos , Estudos Retrospectivos , Taxa de Sobrevida , Neoplasias do Colo do Útero/patologia
17.
ACS Cent Sci ; 4(9): 1274-1290, 2018 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-30276263

RESUMO

Mucin-type O-glycosylation is initiated by a family of polypeptide GalNAc-transferases (GalNAc-Ts) which are type-II transmembrane proteins that contain Golgi luminal catalytic and lectin domains that are connected by a flexible linker. Several GalNAc-Ts, including GalNAc-T4, show both long-range and short-range prior glycosylation specificity, governed by their lectin and catalytic domains, respectively. While the mechanism of the lectin-domain-dependent glycosylation is well-known, the molecular basis for the catalytic-domain-dependent glycosylation of glycopeptides is unclear. Herein, we report the crystal structure of GalNAc-T4 bound to the diglycopeptide GAT*GAGAGAGT*TPGPG (containing two α-GalNAc glycosylated Thr (T*), the PXP motif and a "naked" Thr acceptor site) that describes its catalytic domain glycopeptide GalNAc binding site. Kinetic studies of wild-type and GalNAc binding site mutant enzymes show the lectin domain GalNAc binding activity dominates over the catalytic domain GalNAc binding activity and that these activities can be independently eliminated. Surprisingly, a flexible loop protruding from the lectin domain was found essential for the optimal activity of the catalytic domain. This work provides the first structural basis for the short-range glycosylation preferences of a GalNAc-T.

18.
J Contemp Dent Pract ; 19(3): 278-282, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29603698

RESUMO

AIM: This study aims to evaluate the effect of erbium: Yttrium-aluminum-garnet (Er:YAG) laser irradiation on the enamel microshear bond strength (µSBS), followed by the utilization of etch-and-rinse and universal adhesive systems. MATERIALS AND METHODS: A total of 32 molars were sectioned in the mesiodistal direction producing 64 samples that were randomized into two groups (n = 32): single bond 2 (SB2) (etch-and-rinse system; 3M), SB universal (SBU) (universal etching system; The SB2 and SBU groups were then divided into two subgroups (n = 16): (i) enamel was irradiated with an Er:YAG laser (λ = 2.94 µm, 60 mJ, 10 Hz), and (ii) enamel served as a control. The samples were restored with TPH3 (Dentsply), stored in artificial saliva for 24 hours, and subjected to a micro-shear test. RESULTS: Kruskal-Wallis (p < 0.05) and Mann-Whitney U tests indicated no significant differences in uSBS between the groups, and the fractures were predominately at the resin-enamel interface. CONCLUSION: The previous irradiation of enamel with Er:YAG laser does not interfere with the performance of simplified two-step etch-and-rinse and universal adhesive systems. CLINICAL SIGNIFICANCE: The increasing use of Er:YAG laser is important to evaluate the influence of this irradiation on the adhesion of restorative materials. Thus, to obtain the longevity of the restorative procedures, it is necessary to know the result of the association of the present adhesive systems to the irradiated substrate.


Assuntos
Cimentos Dentários/uso terapêutico , Esmalte Dentário/cirurgia , Lasers de Estado Sólido/uso terapêutico , Alumínio , Colagem Dentária/métodos , Corrosão Dentária/métodos , Humanos , Melhoria de Qualidade , Ítrio
19.
Chemistry ; 24(33): 8382-8392, 2018 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-29601100

RESUMO

The family of polypeptide N-acetylgalactosamine (GalNAc) transferases (GalNAc-Ts) orchestrates the initiating step of mucin-type protein O-glycosylation by transfer of GalNAc moieties to serine and threonine residues in proteins. Deficiencies and dysregulation of GalNAc-T isoenzymes are related to different diseases. Recently, it has been demonstrated that an inactive GalNAc-T2 mutant (F104S), which is not located at the active site, induces low levels of high-density lipoprotein cholesterol (HDL-C) in humans. Herein, the molecular basis for F104S mutant inactivation has been deciphered. Saturation transfer difference NMR spectroscopy experiments demonstrate that the mutation induces loss of binding to peptide substrates. Analysis of the crystal structure of the F104S mutant bound to UDP-GalNAc (UDP=uridine diphosphate), combined with molecular dynamics (MD) simulations, has revealed that the flexible loop is disordered and displays larger conformational changes in the mutant enzyme than that in the wild-type (WT) enzyme. 19 F NMR spectroscopy experiments reveal that the WT enzyme only reaches the active state in the presence of UDP-GalNAc, which provides compelling evidence that GalNAc-T2 adopts a UDP-GalNAc-dependent induced-fit mechanism. The F104S mutation precludes the enzyme from achieving the active conformation and concomitantly binding peptide substrates. This study provides new insights into the catalytic mechanism of the large family of GalNAc-Ts and how these enzymes orchestrate protein O-glycosylation.


Assuntos
Mucina-1/análise , Mucina-1/química , Mucinas/química , N-Acetilgalactosaminiltransferases/análise , N-Acetilgalactosaminiltransferases/química , Difosfato de Uridina/química , Catálise , Domínio Catalítico , Glicosilação , Humanos , Simulação de Dinâmica Molecular , Polipeptídeo N-Acetilgalactosaminiltransferase
20.
Nat Commun ; 8(1): 1959, 2017 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-29208955

RESUMO

The polypeptide GalNAc-transferases (GalNAc-Ts), that initiate mucin-type O-glycosylation, consist of a catalytic and a lectin domain connected by a flexible linker. In addition to recognizing polypeptide sequence, the GalNAc-Ts exhibit unique long-range N- and/or C-terminal prior glycosylation (GalNAc-O-Ser/Thr) preferences modulated by the lectin domain. Here we report studies on GalNAc-T4 that reveal the origins of its unique N-terminal long-range glycopeptide specificity, which is the opposite of GalNAc-T2. The GalNAc-T4 structure bound to a monoglycopeptide shows that the GalNAc-binding site of its lectin domain is rotated relative to the homologous GalNAc-T2 structure, explaining their different long-range preferences. Kinetics and molecular dynamics simulations on several GalNAc-T2 flexible linker constructs show altered remote prior glycosylation preferences, confirming that the flexible linker dictates the rotation of the lectin domain, thus modulating the GalNAc-Ts' long-range preferences. This work for the first time provides the structural basis for the different remote prior glycosylation preferences of the GalNAc-Ts.


Assuntos
N-Acetilgalactosaminiltransferases/química , N-Acetilgalactosaminiltransferases/metabolismo , Peptídeos/química , Peptídeos/metabolismo , Domínios e Motivos de Interação entre Proteínas , Sequência de Aminoácidos , Sítios de Ligação , Domínio Catalítico , Quimera/genética , Clonagem Molecular , Glicopeptídeos/química , Glicopeptídeos/metabolismo , Glicosilação , Humanos , Cinética , Lectinas/química , Lectinas/metabolismo , Modelos Moleculares , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Mutagênese Sítio-Dirigida , N-Acetilgalactosaminiltransferases/genética , Ligação Proteica , Conformação Proteica , Especificidade por Substrato , Polipeptídeo N-Acetilgalactosaminiltransferase
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