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1.
J Biol Chem ; 299(11): 105330, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37820866

RESUMO

Cell cycle errors can lead to mutations, chromosomal instability, or death; thus, the precise control of cell cycle progression is essential for viability. The nutrient-sensing posttranslational modification, O-GlcNAc, regulates the cell cycle allowing one central control point directing progression of the cell cycle. O-GlcNAc is a single N-acetylglucosamine sugar modification to intracellular proteins that is dynamically added and removed by O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA), respectively. These enzymes act as a rheostat to fine-tune protein function in response to a plethora of stimuli from nutrients to hormones. O-GlcNAc modulates mitogenic growth signaling, senses nutrient flux through the hexosamine biosynthetic pathway, and coordinates with other nutrient-sensing enzymes to progress cells through Gap phase 1 (G1). At the G1/S transition, O-GlcNAc modulates checkpoint control, while in S Phase, O-GlcNAcylation coordinates the replication fork. DNA replication errors activate O-GlcNAcylation to control the function of the tumor-suppressor p53 at Gap Phase 2 (G2). Finally, in mitosis (M phase), O-GlcNAc controls M phase progression and the organization of the mitotic spindle and midbody. Critical for M phase control is the interplay between OGT and OGA with mitotic kinases. Importantly, disruptions in OGT and OGA activity induce M phase defects and aneuploidy. These data point to an essential role for the O-GlcNAc rheostat in regulating cell division. In this review, we highlight O-GlcNAc nutrient sensing regulating G1, O-GlcNAc control of DNA replication and repair, and finally, O-GlcNAc organization of mitotic progression and spindle dynamics.


Assuntos
Mitose , Processamento de Proteína Pós-Traducional , Acetilglucosamina/metabolismo , Acetilglucosaminidase/metabolismo , Mutação , N-Acetilglucosaminiltransferases/genética , N-Acetilglucosaminiltransferases/metabolismo , Transdução de Sinais , Humanos , Animais
2.
Public Health ; 232: 82-85, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38749152

RESUMO

OBJECTIVE: In this study, we describe community-based nonpharmaceutical interventions (NPIs) incorporated into COVID-19 mitigation protocols, and SARS-CoV-2 incidence at five faith-based summer camps in the US. STUDY DESIGN: Retrospective cohort study. METHODS: Six southeastern states within the United States (13 sites) were assessed from May 30 to August 14, 2021 (13 sites; N = 13,132; May-August 2021). Camp mitigation policies and NPIs (including masking, vaccinations, meal arrangements, physical distancing, pre-arrival testing, symptom screening, quarantine/isolation, and ventilation upgrades), and SARS-CoV-2 infections were tracked at each site. RESULTS: The symptomatic primary case attack rate was 24.7 (range: 0.0-120.0) cases per 100,000 people per week. Fewer infections were observed in camps with greater mitigation protocols. CONCLUSION: These findings suggest that nonpharmaceutical mitigation can promote stable access to youth programs for historically vaccine-hesitant subgroups. Policy recommendations for nonpharmaceutical interventions to prevent respiratory viral transmission in overnight youth faith-based camp settings may include outdoor activities, accessible symptomatic tests, prearrival testing, indoor mask use, small cohorts, physical distancing, and protocols to minimize staff exposures during time off.


Assuntos
COVID-19 , Acampamento , Humanos , COVID-19/prevenção & controle , COVID-19/epidemiologia , Estudos Retrospectivos , Adolescente , Feminino , Masculino , SARS-CoV-2 , Sudeste dos Estados Unidos/epidemiologia , Distanciamento Físico , Quarentena , Criança , Incidência , Adulto Jovem
3.
BMC Health Serv Res ; 23(1): 574, 2023 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-37270535

RESUMO

BACKGROUND: Sustainable Development Goal (SDG) indicator 3.b.3 monitors progress in medicines' accessibility for adults and has significant limitations when applying to medicines for children. An adapted indicator methodology was developed to fill this gap, but no proof of its robustness exists. We provide this evidence through sensitivity analyses. METHODS: Data on availability and prices of child medicines from ten historical datasets were combined to create datasets for analysis: Dataset 1 (medicines selected at random) and Dataset 2 (preference given to available medicines, to better capture affordability of medicines). A base case scenario and univariate sensitivity analyses were performed to test critical components of the methodology, including the new variable of number of units needed for treatment (NUNT), disease burden (DB) weighting, and the National Poverty Line (NPL) limits. Additional analyses were run on a continuously smaller basket of medicines to explore the minimum number of medicines required. Mean facility scores for access were calculated and compared. RESULTS: The mean facility score for Dataset 1 and Dataset 2 within the base case scenario was 35.5% (range 8.0-58.8%) and 76.3% (range 57.2-90.6%). Different NUNT scenarios led to limited variations in mean facility scores of + 0.1% and -0.2%, or differences of + 4.4% and -2.1% at the more critical NPL of $5.50 (Dataset 1). For Dataset 2, variations to the NUNT generated differences of + 0.0% and -0.6%, at an NPL of $5.50 the differences were + 5.0 and -2.0%. Different approaches for weighting for DB induced considerable fluctuations of 9.0% and 11.2% respectively. Stable outcomes with less than 5% change in mean facility score were observed for a medicine basket down to 12 medicines. For smaller baskets, scores increased more rapidly with a widening range. CONCLUSION: This study has confirmed that the proposed adaptations to make SDG indicator 3.b.3 appropriate for children are robust, indicating that they could be an important addition to the official Global Indicator Framework. At least 12 child-appropriate medicines should be surveyed to obtain meaningful outcomes. General concerns that remain about the weighting of medicines for DB and the NPL should be considered at the 2025 planned review of this framework.


Assuntos
Medicamentos Essenciais , Desenvolvimento Sustentável , Adulto , Humanos , Acessibilidade aos Serviços de Saúde , Inquéritos e Questionários , Efeitos Psicossociais da Doença
4.
Molecules ; 28(11)2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37298941

RESUMO

Pain is one of the most prevalent and difficult to manage symptoms in cancer patients, and conventional drugs present a range of adverse reactions. The development of ß-cyclodextrins (ß-CD) complexes has been used to avoid physicochemical and pharmacological limitations due to the lipophilicity of compounds such as p-Cymene (PC), a monoterpene with antinociceptive effects. Our aim was to obtain, characterize, and measure the effect of the complex of p-cymene and ß-cyclodextrin (PC/ß-CD) in a cancer pain model. Initially, molecular docking was performed to predict the viability of complex formation. Afterward, PC/ß-CD was obtained by slurry complexation, characterized by HPLC and NMR. Finally, PC/ß-CD was tested in a Sarcoma 180 (S180)-induced pain model. Molecular docking indicated that the occurrence of interaction between PC and ß-CD is favorable. PC/ß-CD showed complexation efficiency of 82.61%, and NMR demonstrated PC complexation in the ß-CD cavity. In the S180 cancer pain model, PC/ß-CD significantly reduced the mechanical hyperalgesia, spontaneous nociception, and nociception induced by non-noxious palpation at the doses tested (p < 0.05) when compared to vehicle differently from free PC (p > 0.05). Therefore, the complexation of PC in ß-CD was shown to improve the pharmacological effect of the drug as well as reducing the required dose.


Assuntos
Dor do Câncer , Ciclodextrinas , Neoplasias , beta-Ciclodextrinas , Humanos , Camundongos , Animais , Simulação de Acoplamento Molecular , beta-Ciclodextrinas/química , Dor/tratamento farmacológico , Dor/etiologia , Analgésicos/farmacologia , Analgésicos/uso terapêutico , Analgésicos/química , Solubilidade
5.
Glycoconj J ; 39(5): 653-661, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35536494

RESUMO

At cell surface gangliosides might associate with signal transducers proteins, grown factor receptors, integrins, small G-proteins and tetraspanins establishing microdomains, which play important role in cell adhesion, cell activation, motility, and growth. Previously, we reported that GM2 and GM3 form a heterodimer that interacts with the tetraspanin CD82, controlling epithelial cell mobility by inhibiting integrin-hepatocyte growth factor-induced cMet tyrosine kinase signaling. By using molecular dynamics simulations to study the molecular basis of GM2/GM3 interaction we demonstrate, here, that intracellular levels of Ca2+ mediate GM2/GM3 complexation via electrostatic interaction with their carboxyl groups, while hydrogen bonds between the ceramide groups likely aid stabilizing the complex. The presence of GM2/GM3 complex alters localization of CD82 on cell surface and therefore downstream signalization. These data contribute for the knowledge of how glycosylation may control signal transduction and phenotypic changes.


Assuntos
Gangliosídeo G(M3) , Proteína Kangai-1 , Adesão Celular , Movimento Celular , Proteína Kangai-1/metabolismo , Transdução de Sinais
6.
Phys Chem Chem Phys ; 24(37): 22845-22858, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36112360

RESUMO

Azithromycin (AZM) is a well-known macrolide-type antibiotic that has been used in the treatment of infections and inflammations. Knowledge of the predominant molecular structure in solution is a prerequisite for an understanding of the interactions of the drug in biological media. Experimental structural determination can be carried out for samples in solid-state (X-ray diffraction technique) and gas phase (electron diffraction experiment). In solution, spectroscopic methods can be used to extract valuable information which combined with quantum chemical calculations can lead to the determination of the preferred molecular structures to be observed when a given solute is dissolved in each solvent. That is precisely the aim of this work. We used experimental NMR chemical shift data (in CDCl3) as a reference for comparison with Density Functional Theory (DFT) NMR calculations, with geometry optimized having as guess input two crystallographic structures available in the literature with the configuration of all chiral carbon atoms inverted, named here A and B. The Polarizable Continuum Model (PCM) was used to describe the solvent effects (chloroform) including five explicit CHCl3 solvent molecules, which we believe can account for short and long-range solute-solvent interactions. Analysis of calculated thermodynamic, NMR chemical shift, MAE (Mean Absolute Error), and spin-spin coupling constant values revealed that both supposable C3R-C5S (named M2-A) and C3S-C5R (named M2-B) structures are equally probable to exist in chloroform solution. In addition, we found that the heavy atoms' conformation is reasonably similar in the solid-state and chloroform solution; however, regarding the OH groups, the spatial orientations are rather different with intramolecular OH⋯N and OH⋯O hydrogen bonds present in solution and with some of them being absent in the X-ray structure probably due to crystal packing effects.


Assuntos
Azitromicina , Clorofórmio , Antibacterianos , Carbono , Teoria Quântica , Soluções , Solventes/química , Termodinâmica
7.
Sensors (Basel) ; 22(5)2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35270964

RESUMO

This paper presents the results of studies on reducing the amount of vibrations in different frequency ranges generated by a combustion engine through the use of different types of engine mounts. Three different types of engine supports are experimentally and numerically analyzed, namely an elastomeric engine mount, an elastomeric engine mount with a hydraulic component and standard decoupling, and an elastomeric engine mount with a hydraulic component and a modified decoupler-with this engineering design being a novelty in the literature. Experimental tests that considered different excitation frequencies were performed for the three types of engine mounts. Experimental data for stiffness and damping were used to obtain nonlinear mathematical models of the two systems with hydraulic components through the use of an Artificial Neural Network (ANN). For the results, all of the mathematical models presented coefficients of determination, R2, greater than 0.985 for both stiffness and damping, showing an excellent fit for the nonlinear experimental data. Numerical results using a quarter-car suspension model showed a large reduction in vibration amplitudes for the first vibration model when using the hydraulic systems, with values ranging between 48.58% and 66.47%, depending on the tests. The modified system presented smaller amplitudes and smoother behavior when compared to the standard hydraulic model.


Assuntos
Modelos Teóricos , Redes Neurais de Computação , Elasticidade , Dinâmica não Linear , Vibração
8.
Int J Mol Sci ; 23(19)2022 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-36232558

RESUMO

Kidneys maintain internal milieu homeostasis through a well-regulated manipulation of body fluid composition. This task is performed by the correlation between structure and function in the nephron. Kidney diseases are chronic conditions impacting healthcare programs globally, and despite efforts, therapeutic options for its treatment are limited. The development of chronic degenerative diseases is associated with changes in protein O-GlcNAcylation, a post-translation modification involved in the regulation of diverse cell function. O-GlcNAcylation is regulated by the enzymatic balance between O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA) which add and remove GlcNAc residues on target proteins, respectively. Furthermore, the hexosamine biosynthetic pathway provides the substrate for protein O-GlcNAcylation. Beyond its physiological role, several reports indicate the participation of protein O-GlcNAcylation in cardiovascular, neurodegenerative, and metabolic diseases. In this review, we discuss the impact of protein O-GlcNAcylation on physiological renal function, disease conditions, and possible future directions in the field.


Assuntos
Acetilglucosamina , N-Acetilglucosaminiltransferases , Acetilglucosamina/metabolismo , Hexosaminas/metabolismo , Homeostase , Rim/metabolismo , N-Acetilglucosaminiltransferases/metabolismo , Processamento de Proteína Pós-Traducional
9.
Int J Mol Sci ; 23(2)2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-35055044

RESUMO

Renal proximal tubule cells (PTECs) act as urine gatekeepers, constantly and efficiently avoiding urinary protein waste through receptor-mediated endocytosis. Despite its importance, little is known about how this process is modulated in physiologic conditions. Data suggest that the phosphoinositide-3-kinase (PI3K)/protein kinase B (AKT) pathway regulates PTEC protein reabsorption. Here, we worked on the hypothesis that the physiologic albumin concentration and PI3K/AKT pathway form a positive feedback loop to expand endocytic capacity. Using LLC-PK1 cells, a model of PTECs, we showed that the PI3K/AKT pathway is required for megalin recycling and surface expression, affecting albumin uptake. Inhibition of this pathway stalls megalin at EEA1+ endosomes. Physiologic albumin concentration (0.01 mg/mL) activated AKT; this depends on megalin-mediated albumin endocytosis and requires previous activation of PI3K/mTORC2. This effect is correlated to the increase in albumin endocytosis, a phenomenon that we refer to as "albumin-induced albumin endocytosis". Mice treated with L-lysine present decreased albumin endocytosis leading to proteinuria and albuminuria associated with inhibition of AKT activity. Renal cortex explants obtained from control mice treated with MK-2206 decreased albumin uptake and promoted megalin internalization. Our data highlight the mechanism behind the capacity of PTECs to adapt albumin reabsorption to physiologic fluctuations in its filtration, avoiding urinary excretion.


Assuntos
Células Epiteliais/metabolismo , Retroalimentação Fisiológica , Túbulos Renais Proximais/metabolismo , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Albuminas/metabolismo , Animais , Biomarcadores , Endocitose , Células Epiteliais/efeitos dos fármacos , Imunofluorescência , Expressão Gênica , Túbulos Renais Proximais/citologia , Masculino , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Transporte Proteico , Transdução de Sinais/efeitos dos fármacos
10.
Water Sci Technol ; 85(3): 943-960, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35166712

RESUMO

Partial nitritation anammox (PNA) membrane aerated biofilm reactors (MABRs) have the potential to be employed in mainstream wastewater treatment and can drastically decrease the energy and carbon requirements for nitrogen removal. Previous PNA MABR studies have looked at 1-stage systems, but no study has holistically compared the performance of different MABR configurations. In this study, a PNA MABR was mechanistically modelled to determine the impact of the reactor configuration (1-stage, hybrid, or 2-stage system) on the location of the preferred niche for anammox bacteria and the overall nitrogen removal performance. Results from this study show that the 2-stage configuration, which used an MABR with a thin biofilm for nitritation and a moving bed biofilm reactor for anammox, had a 20% larger nitrogen removal rate than the 1-stage or hybrid configurations. This suggests that an MABR should focus on maximizing nitrite production with anammox implemented in a second-stage biofilm reactor to achieve the most cost-effective nitrogen removal. However, the optimal configuration will likely be facility specific, as each facility differs in operating costs, construction costs, footprint, and effluent limits. Additional experimentation is required to confirm these results, but this work narrows the number of viable configurations that need to be tested. The results of this study will inform researchers and engineers how to best implement PNA MABRs in mainstream nitrogen removal at larger scales.


Assuntos
Compostos de Amônio , Reatores Biológicos , Oxidação Anaeróbia da Amônia , Biofilmes , Nitritos , Nitrogênio , Oxirredução , Águas Residuárias
11.
Development ; 145(22)2018 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-30355725

RESUMO

Disorders of N-linked glycosylation are increasingly reported in the literature. However, the targets that are responsible for the associated developmental and physiological defects are largely unknown. Bone morphogenetic proteins (BMPs) act as highly dynamic complexes to regulate several functions during development. The range and strength of BMP activity depend on interactions with glycosylated protein complexes in the extracellular milieu. Here, we investigate the role of glycosylation for the function of the conserved extracellular BMP antagonist Short gastrulation (Sog). We identify conserved N-glycosylated sites and describe the effect of mutating these residues on BMP pathway activity in Drosophila Functional analysis reveals that loss of individual Sog glycosylation sites enhances BMP antagonism and/or increases the spatial range of Sog effects in the tissue. Mechanistically, we provide evidence that N-terminal and stem glycosylation controls extracellular Sog levels and distribution. The identification of similar residues in vertebrate Chordin proteins suggests that N-glycosylation may be an evolutionarily conserved process that adds complexity to the regulation of BMP activity.


Assuntos
Proteínas Morfogenéticas Ósseas/metabolismo , Proteínas de Drosophila/metabolismo , Sequência de Aminoácidos , Animais , Sequência Conservada , Proteínas de Drosophila/química , Drosophila melanogaster/embriologia , Drosophila melanogaster/metabolismo , Embrião não Mamífero/metabolismo , Espaço Extracelular/metabolismo , Glicosilação , Proteínas Mutantes/metabolismo , Polissacarídeos/metabolismo , Ligação Proteica , Asas de Animais/metabolismo
12.
Public Health ; 191: 85-90, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33556639

RESUMO

The field of bereavement research and care is at a tipping point. The introduction of prolonged grief disorder (PGD) in the International Classification of Diseases (ICD-11) has ignited clinical interest in this new disorder, along with debate over challenges in validating and implementing these new criteria. At the same time, the global COVID-19 pandemic has launched several local and international efforts to provide urgent support and comfort for individuals and communities suffering from grief. Recently, grief experts have called for a collective response to these complicated bereavements and possible increase in PGD due to COVID-19. Here we outline a new European network that aims to unite a community of grief researchers and clinicians to provide accessible, evidence-based support particularly during times of unprecedent crisis. The Bereavement Network Europe (BNE) has been developed with two main aims. Firstly, to develop expert agreed, internationally acceptable guidelines for bereavement care through a three-tiered approach. Secondly, to provide a platform for researchers and clinicians to share knowledge, collaborate, and develop consensus protocols to facilitate the introduction of PGD to diverse stakeholders. This article outlines the current status and aims of the BNE along with the plans for upcoming network initiatives and the three-tiered bereavement care guidelines in response to the COVID-19 pandemic.


Assuntos
COVID-19 , Redes Comunitárias , Atenção à Saúde/organização & administração , Pesar , Classificação Internacional de Doenças , Luto , Europa (Continente)/epidemiologia , Humanos , Modelos Organizacionais , Guias de Prática Clínica como Assunto
13.
HIV Med ; 21(6): 378-385, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32065713

RESUMO

OBJECTIVES: Development of novel antiretrovirals aims at reducing long-term toxicities. Tenofovir disoproxil fumarate (TDF) has been associated with potential nephrotoxicity. The aim of our study was to assess the impact of switching from TDF to tenofovir alafenamide (TAF) on functional nephropathy and lipid parameters in a real-life setting. METHODS: We retrospectively analysed data from 347 HIV-infected patients switching from a TDF- to a TAF-containing regimen between April and December 2016. Sociodemographic, clinical and laboratory data were collected at TDF-to-TAF switch, and at 3 and 6 months thereafter. Proteinuria and albuminuria were classified according to Kidney Diseases Improving Global Outcomes (KDIGO) guidelines. RESULTS: At time of switch, moderately and severely increased proteinuria was detected in 32% and 8% of patients, respectively; however, urine dipstick analysis was negative in 84% and 42%, respectively. Moderately and severely increased albuminuria was found in 17% and 3% of patients, respectively. In patients with a urinary protein-to-creatinine ratio (UPCR) ≥ 150 mg/g, the mean value declined from 416 mg/g at baseline to 272 mg/g (P < 0.001) and 242 mg/g (P < 0.001) after 3 and 6 months, respectively. Patients with an albumin-to-creatinine ratio (UACR) ≥ 30 mg/g showed no significant decrease of albuminuria. Mean total cholesterol increased from 187 mg/dL at baseline to 202 (P < 0.001) and 208 mg/dL (P < 0.001) at 3 and 6 months, respectively, and mean low-density lipoprotein (LDL) cholesterol increased from 114 mg/dL at baseline to 124 (P < 0.001) and 128 mg/dL (P < 0.001), respectively. As mean high-density lipoprotein (HDL) cholesterol increased from 50 mg/dL at baseline to 54 (P < 0.001) and 57 mg/dL (P < 0.001) at 3 and 6 months, respectively, the LDL:HDL ratio remained stable. CONCLUSIONS: In an aging HIV-infected cohort, proteinuria and albuminuria were common findings and were underdiagnosed via urine dipstick. Our real-life data suggest that laboratory markers of moderately/severely increased proteinuria improved after TDF-to-TAF-switch. Lipid profiles were not aggravated. Long-term follow-up is needed to determine the clinical benefit of the TDF-to-TAF switch.


Assuntos
Alanina/administração & dosagem , Infecções por HIV/tratamento farmacológico , Proteinúria/epidemiologia , Tenofovir/análogos & derivados , Tenofovir/administração & dosagem , Fatores Etários , Alanina/efeitos adversos , Albuminúria/induzido quimicamente , Albuminúria/epidemiologia , LDL-Colesterol/metabolismo , Substituição de Medicamentos , Feminino , Infecções por HIV/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Proteinúria/induzido quimicamente , Estudos Retrospectivos , Tenofovir/efeitos adversos , Fatores de Tempo
14.
Br J Dermatol ; 182(3): 698-707, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31141158

RESUMO

BACKGROUND: The Ehlers-Danlos syndromes (EDS) consist of 13 subtypes with overlapping features including joint hypermobility, skin and vascular fragility and generalized connective tissue friability. As DNA analysis has become the gold standard for investigation of EDS, transmission electron microscopy (TEM) in clinical practice is decreasing. However, owing to the use of next-generation sequencing, the frequency of variants of uncertain significance (VUS) identified using DNA analysis is increasing. We hypothesized that TEM can provide evidence for or against pathogenicity of VUS. OBJECTIVES: The aim of this study was to evaluate the role of TEM in the diagnosis of EDS subtypes. METHODS: Data were collected from patients who underwent a skin biopsy between October 2012 and March 2017 at the London EDS National Diagnostic Service. TEM biopsies were categorized as 'normal' or 'abnormal' according to the description and conclusion in the TEM reports. Definitive diagnoses were reached via a combination of clinical features, structural and functional studies and DNA investigations. RESULTS: The analysis included 177 patients, comprising 30 abnormal and 147 normal TEM reports. A definitive diagnosis of monogenic EDS subtypes was made in 24 patients. Overall, 17 of these 24 patients (71%) had an abnormal biopsy report and seven (29%) had a normal biopsy report. No TEM findings were specifically associated with any EDS subtype, although collagen flowers were present in most patients with a genetically confirmed diagnosis of classical EDS. CONCLUSIONS: TEM analysis of collagen structure may have the potential to provide evidence for or against the pathogenicity of a VUS, but more work is needed to establish a clear role for TEM in this process. What's already known about this topic? Collagen fibril abnormalities can be seen in several Ehlers-Danlos syndrome (EDS) subtypes. What does this study add? This study provides clinical data, transmission electron microscopy (TEM) data and molecular data of one of the largest groups of patients suspected to have a monogenetic EDS subtype. No TEM findings were specifically associated with an EDS subtype. There was a higher percentage (71%) of abnormal biopsy findings in patients with a definitive diagnosis of a monogenetic EDS subtype and where a class 4/5 genetic variant was present.


Assuntos
Síndrome de Ehlers-Danlos , Colágeno , Síndrome de Ehlers-Danlos/diagnóstico , Síndrome de Ehlers-Danlos/genética , Humanos , Londres , Microscopia Eletrônica , Síndrome
15.
J Chem Inf Model ; 60(2): 500-512, 2020 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-31738559

RESUMO

Carbon nanohorns (CNH) have been considered potential anticancer drug carriers, such as the cisplatin drug (cddp), due to their low toxicity, high purity, drug-loading capacity, and biodegradation routes. However, when it comes to nanomedicine applications, chemical functionalization is an essential step in order to overcome undesirable properties of these nanomaterials, such as the high hydrophobicity, low reactivity, and low dispersibility in polar solvents. In this context, the present study involved the modeling of new CNH topologies based on chemical oxidation and reduction mechanisms and the investigation of the influence of these modified structures on the dynamics and stability of inclusion complexes with cddp. The results indicated that these functionalization strategies lead to the opening of nanowindows on the CNH surfaces, which would constitute the main route for drug release, as reported by experimentalists. Also, our results showed that the insertion of polar functional groups on the oxidized CNH (CNHox-N) contributed to an improvement of the cddp@CNHox-N biocompatibility due to the greater number of hydrogen bonds formed with the solvent. Despite the favorable formation of all complexes, the binding free energies pointed out that the oxidation process made the cddp@CNHox-N complexes slightly less stable than the ones with pristine and reduced CNH. Besides, the results suggest the possibility to tune the complex stability by controlling the oxidation degree, which could be explored by the experimentalists in order to design controlled drug delivery systems based on CNH nanocarriers.


Assuntos
Cisplatino/química , Portadores de Fármacos/química , Simulação de Dinâmica Molecular , Nanotubos de Carbono/química , Liberação Controlada de Fármacos , Ligação de Hidrogênio , Conformação Molecular , Oxirredução , Propriedades de Superfície , Termodinâmica
16.
Ultrasound Obstet Gynecol ; 56(6): 901-905, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-31763722

RESUMO

OBJECTIVES: To determine if large-for-gestational age (LGA) diagnosed during second-trimester ultrasound examination is associated with the development of gestational diabetes mellitus (GDM) and LGA at birth. METHODS: This was a retrospective cohort study of all pregnant women who underwent a second-trimester anatomy ultrasound examination between 18 and 22 weeks at our institution from 2012 to 2017. Patients were included in the LGA group if estimated fetal weight and/or fetal abdominal circumference was ≥ 90th percentile for gestational age. Patients with a history of pre-GDM, multiple gestation, preterm delivery, use of betamethasone or fetal anomaly were excluded. The control group consisted of appropriate-for-gestational-age (AGA) pregnancies that were scanned at 18-22 weeks during the study period. AGA was defined as EFW > 10th percentile and ≤ 89th percentile. Prenatal and delivery records were reviewed and demographic and outcome variables were collected. Multivariable logistic regression models were applied to assess the impact of LGA diagnosed in the second trimester on the development of GDM and LGA at birth (birth weight ≥ 90th percentile). RESULTS: The study population included 756 patients with a LGA fetus and 756 with an AGA fetus on second-trimester ultrasound examination. In patients with a LGA fetus diagnosed during the second-trimester ultrasound examination, the incidence of GDM was 6.0% and the incidence of LGA at birth was 14.9%. Among patients with a LGA fetus in the second trimester, those who developed GDM or LGA at birth were significantly older and were more likely to be obese. Moreover, parity was associated with neonatal LGA (P = 0.0003) but not with GDM (P = 0.82). On multivariable logistic regression analysis with adjustment for age, parity, change in gestational body mass index, obesity, ethnicity and neonatal sex, LGA diagnosed during the second trimester was associated significantly with GDM (adjusted odds ratio (aOR), 2.54; 95% CI, 1.29-5.03; P = 0.007) and LGA at birth (aOR, 6.85; 95% CI, 3.60-13.05; P < 0.0001). CONCLUSIONS: LGA diagnosed during second-trimester ultrasound examination is associated with the development of GDM and LGA at birth, independent of known risk factors, and could be used to identify these women earlier for intervention. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Diabetes Gestacional/diagnóstico , Macrossomia Fetal/diagnóstico , Feto/embriologia , Segundo Trimestre da Gravidez , Ultrassonografia Pré-Natal , Adulto , Peso ao Nascer , Feminino , Desenvolvimento Fetal , Peso Fetal , Feto/diagnóstico por imagem , Feto/fisiopatologia , Humanos , Recém-Nascido , Modelos Logísticos , Gravidez , Estudos Retrospectivos , Fatores de Risco , Circunferência da Cintura
17.
J Phys Chem A ; 124(25): 5182-5193, 2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-32466649

RESUMO

Among 20 compounds isolated from the extracts of Ouratea ferruginea the 5,4'-dihydroxy-7,5',3'-trimethoxyisoflavone (9) showed the best inhibitory effect on glutathione S-transferase (GST) and so deserves our attention. In this work we investigated the preferred molecular structure of 9 in chloroform solution using the density functional theory (DFT) and molecular dynamics simulation. Comparison between experimental 1H NMR data in CDCl3 solution and calculated chemical shifts enabled us to precisely determine the conformation adopted by 9 in solution, which can be used in further theoretical studies involving interaction with biological targets. Moreover, the experimental NMR data were used as reference to assess the ability of DFT based methods to predict 1H NMR spectrum in solution for organic compounds. Among various DFT functionals the hybrid B3LYP was the most adequate for the calculation of chemical shifts in what CHn protons are concerned. Regarding the OH hydrogen, inclusion of explicit CHCl3 solvent molecules adequately placed around the solute led to good agreement with the experimental chemical shifts (in CDCl3). It is a well-known fact that theoretical prediction of chemical shifts for OH hydrogens poses as a challenge and also revealed that the way the solvent effects are included in the DFT calculations is crucial for the right prediction of the whole 1H NMR spectrum. It was found in this work that a supermolecule solute-solvent calculation with a minimum of four CHCl3 molecules is enough to correctly reproduce the 1H NMR experimental profile observed in solution, revealing that the calculated solvated structure used to reproduce the NMR chemical shifts is not unique.

18.
J Dairy Sci ; 103(8): 7124-7140, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32600762

RESUMO

Within the rumen, nitrate can serve as an alternative sink for aqueous hydrogen [H2(aq)] accumulating during fermentation, producing nitrite, which ideally is further reduced to ammonium but can accumulate under conditions not yet explained. Defaunation has also been associated with decreased methanogenesis in meta-analyses because protozoa contribute significantly to H2 production. In the present study, we applied a 2 × 2 factorial treatment arrangement in a 4 × 4 Latin square design to dual-flow continuous culture fermentors (n = 4). Treatments were control without nitrate (-NO3-) versus with nitrate (+NO3-; 1.5% of diet dry matter), factorialized with normal protozoa (faunated, FAUN) versus defaunation (DEF) by decreasing the temperature moderately and changing filters over the first 4 d of incubation. We detected no main effects of DEF or interaction of faunation status with +NO3-. The main effect of +NO3- increased H2(aq) by 11.0 µM (+117%) compared with -NO3-. The main effect of +NO3- also decreased daily CH4 production by 8.17 mmol CH4/d (31%) compared with -NO3-. Because there were no treatment effects on neutral detergent fiber digestibility, the main effect of +NO3- also decreased CH4 production by 1.43 mmol of CH4/g of neutral detergent fiber degraded compared with -NO3-. There were no effects of treatment on other nutrient digestibilities, N flow, or microbial N flow per gram of nutrient digested. The spike in H2(aq) after feeding NO3- provides evidence that methanogenesis is inhibited by substrate access rather than concentration, regardless of defaunation, or by direct inhibition of NO2-. Methanogens were not decreased by defaunation, suggesting a compensatory increase in non-protozoa-associated methanogens or an insignificant contribution of protozoa-associated methanogens. Despite adaptive reduction of NO3- to NH4+ and methane inhibition in continuous culture, practical considerations such as potential to depress dry matter intake and on-farm ration variability should be addressed before considering NO3- as an avenue for greater sustainability of greenhouse gas emissions in US dairy production.


Assuntos
Fibras na Dieta/metabolismo , Eucariotos/metabolismo , Hidrogênio/metabolismo , Metano/metabolismo , Microbiota , Nitratos/farmacologia , Compostos de Amônio/metabolismo , Animais , Bactérias/metabolismo , Reatores Biológicos , Técnicas de Cultura , Dieta/veterinária , Ingestão de Alimentos , Ácidos Graxos Voláteis/metabolismo , Fermentação/efeitos dos fármacos , Hidrogênio/análise , Nitritos/metabolismo , Nitrogênio/metabolismo , Rúmen/metabolismo
19.
Eat Weight Disord ; 25(4): 999-1010, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31154633

RESUMO

PURPOSE: The present study aimed to compare prevalence rates of childhood maltreatment between patients with severe obesity undergoing bariatric surgery and patients without a surgical procedure. Second purpose was to calculate the association between childhood maltreatment and outcomes 6 and 12 months after a bariatric procedure. METHODS: Childhood maltreatment was assessed using the Childhood Trauma Questionnaire (CTQ) and compared between 120 bariatric surgery patients and 346 non-surgery patients with severe obesity. For the bariatric surgery subgroup, linear mixed models with repeated measures were used to analyze the predictive value of childhood maltreatment on weight outcomes and psychopathology. Additionally, between- and within-group comparisons were calculated to compare patients with and without childhood maltreatment regarding BMI and weight loss (%TWL, %EWL), depression severity (BDI-II), eating disorder psychopathology (EDE-Q), and suicidal ideation (BSS), at baseline, 6- and 12-month assessment. RESULTS: Prevalence rates for childhood maltreatment, depression and suicidal ideation were significantly higher in non-surgery compared to bariatric surgery patients. Within the surgery group, no significant interaction effect between childhood maltreatment and time was found. Hence, childhood maltreatment did not impact the course of body weight, depression and eating disorder psychopathology from pre- to post-surgery. CONCLUSIONS: Significantly higher rates of childhood maltreatment were found within non-surgery patients with obesity in comparison to bariatric surgery patients. Childhood maltreatment did not predict poorer outcomes after surgery. Since history of childhood maltreatment may increase the risk for psychological disturbances, regular screening and, if necessary, psychological support should be offered to both groups. LEVEL OF EVIDENCE: Evidence obtained from well-designed cohort or case-control analytic studies, Level III. CLINICAL TRIAL REGISTRATION: Deutsches Register Klinischer Studien-German Clinical Trials Register: DRKS00003976.


Assuntos
Cirurgia Bariátrica , Maus-Tratos Infantis , Transtornos da Alimentação e da Ingestão de Alimentos , Obesidade Mórbida , Criança , Transtornos da Alimentação e da Ingestão de Alimentos/epidemiologia , Transtornos da Alimentação e da Ingestão de Alimentos/etiologia , Humanos , Obesidade Mórbida/cirurgia , Redução de Peso
20.
Res Sports Med ; 28(2): 241-255, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31345073

RESUMO

Regular moderate physical activity (PA) has been linked to beneficial adaptations in various somatic diseases (e.g. cancer, endocrinological disorders) and a reduction in all-cause mortality from several cardiovascular and neuropsychiatric diseases. This study was designed to investigate acute and prolonged exercise-induced cardio- and neurophysiological responses in endurance runners competing in the Munich Marathon. ReCaP (Running effects on Cognition and Plasticity) is a multimodal and longitudinal experimental study. This study included 100 participants (20-60 years). Six laboratory visits were included during the 3-month period before and the 3-month period after the Munich marathon. The multimodal assessment included laboratory measurements, cardiac and cranial imaging (MRI scans, ultrasound/echocardiography) and neurophysiological methods (EEG and TMS/tDCS), and vessel-analysis (e.g. retinal vessels and wave-reflection analyses) and neurocognitive measurements. The ReCaP study was designed to examine novel exercise-induced cardio- and neurophysiological responses to marathon running at the behavioral, functional and morphological levels. This study will expand our understanding of exercise-induced adaptations and will lead to more individually tailored therapeutic options.


Assuntos
Cognição , Plasticidade Neuronal , Resistência Física , Corrida/fisiologia , Adulto , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
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