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1.
Nanoscale Adv ; 6(10): 2656-2668, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38752136

RESUMO

Organic phosphates (OP) are important nutrient components for living cells in natural environments, where they readily interact with ubiquitous iron phases such as hydrous ferric oxide, ferrihydrite (FHY). FHY partakes in many key bio(geo)chemical reactions including iron-mediated carbon storage in soils, or iron-storage in living organisms. However, it is still unknown how OP affects the formation, structure and properties of FHY. Here, we document how ß-glycerophosphate (GP), a model OP ligand, affects the structure and properties of GP-FHY nanoparticles synthesized by coprecipitation at variable nominal molar P/Fe ratios (0.01 to 0.5). All GP-FHY precipitates were characterized by a maximum solid P/Fe ratio of 0.22, irrespective of the nominal P/Fe ratio. With increasing nominal P/Fe ratio, the specific surface area of the GP-FHY precipitates decreased sharply from 290 to 3 m2 g-1, accompanied by the collapse of their pore structure. The Fe-P local bonding environment gradually transitioned from a bidentate binuclear geometry at low P/Fe ratios to monodentate mononuclear geometry at high P/Fe ratios. This transition was accompanied by a decrease in coordination number of edge-sharing Fe polyhedra, and the loss of the corner-sharing Fe polyhedra. We show that Fe(iii) polymerization is impeded by GP, and that the GP-FHY structure is highly dependent on the P/Fe ratio. We discuss the role that natural OP-bearing Fe(iii) nanophases have in biogeochemical reactions between Fe-P and C species in aquatic systems.

2.
Curr Res Toxicol ; 6: 100167, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38659494

RESUMO

Sunitinib malate is known to cause cardiotoxicity in a sub-population of patients, with heart failure seen in more severe cases. Cardiac progenitor cells (CPCs) have been identified in adult human myocardium and contribute to overall tissue maintenance, with previous work identifying negative impacts of sunitinib on these cells. This study aimed to characterise the toxic effects of sunitinib in human CPCs, applying sunitinib concentrations equivalent to clinical plasma levels to these cells in vitro. Cell viability was reduced by 26.5 ± 6.6 % by 2 µM sunitinib for 24 h (p < 0.01); this concentration also induced fold-change increases in gene expression of: calpain (3.1 ± 0.73, p < 0.05), FAS (2.3 ± 0.8, p < 0.05) and BAX (1.9 ± 0.2, p < 0.05), and a decrease in BCL-2 (3.5 ± 0.0, p < 0.001), vs. control (1.0 ± 0.0). This was affirmed by sunitinib inducing fold changes in protein expression of: calpain-1 (2.5 ± 0.5, p < 0.05); FAS receptor (2.1 ± 0.2, p < 0.05) and BAX (2.1 ± 0.2, p < 0.05) vs. control (1.0 ± 0.0). These results indicated that sunitinib induced apoptosis in CPCs, but negative annexin V staining and lack of protection by caspase inhibitors indicated this was not the cell death pathway activated. Further investigation found sunitinib was concentrated in the lysosomes and autophagosomes within CPCs, but did not induce accumulation of acidic organelles. In conclusion, these data confirm that cell death is caused by sunitinib in CPCs at concentrations equivalent to clinical plasma levels, inducing cell death pathway signals that lead to non-apoptotic cell death.

3.
J Occup Environ Med ; 66(5): e153-e159, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38349316

RESUMO

OBJECTIVE: We examined the impact of health care workers' (HCWs) adjustment to the COVID-19 pandemic on their work-related attitudes and behaviors. METHODS: HCWs ( n = 1468) participated in an observational longitudinal study in which they completed surveys of anxiety and occupational health between 2020 and 2021. RESULTS: Most HCWs reported anxiety that was consistently below the diagnostic threshold (68%) or fell below the threshold within a year (16%). Others reported consistently high (14%) or increasing (2%) anxiety, especially women, younger HCWs, those with a weakened immune system, and allied health professionals. Consistently high or increasing anxiety was associated with poorer job satisfaction, work engagement, perceived supervisor support, burnout, and turnover intentions. CONCLUSIONS: Resources to support HCWs may be focused on those who report consistently high or increasing anxiety to minimize the effects of crises and disasters on the workforce.


Assuntos
Ansiedade , Atitude do Pessoal de Saúde , Esgotamento Profissional , COVID-19 , Pessoal de Saúde , Satisfação no Emprego , SARS-CoV-2 , Local de Trabalho , Humanos , COVID-19/psicologia , COVID-19/epidemiologia , Feminino , Masculino , Adulto , Pessoal de Saúde/psicologia , Pessoa de Meia-Idade , Estudos Longitudinais , Ansiedade/epidemiologia , Ansiedade/psicologia , Local de Trabalho/psicologia , Esgotamento Profissional/epidemiologia , Esgotamento Profissional/psicologia , Inquéritos e Questionários , Reorganização de Recursos Humanos/estatística & dados numéricos , Adaptação Psicológica , Pandemias , Engajamento no Trabalho
4.
Chemistry ; 30(25): e202400544, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38407499

RESUMO

Light can be used to design stimuli-responsive systems. We induce transient changes in the assembly of a low molecular weight gelator solution using a merocyanine photoacid. Through our approach, reversible viscosity changes can be achieved via irradiation, delivering systems where flow can be controlled non-invasively on demand.

5.
bioRxiv ; 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38260250

RESUMO

Fatty acid ß-oxidation (FAO) is a central catabolic pathway with broad implications for organismal health. However, various fatty acids are largely incompatible with standard FAO machinery until they are modified by other enzymes. Included among these are the 4-hydroxy acids (4-HAs)-fatty acids hydroxylated at the 4 (γ) position-which can be provided from dietary intake, lipid peroxidation, and certain drugs of abuse. Here, we reveal that two atypical and poorly characterized acyl-CoA dehydrogenases (ACADs), ACAD10 and ACAD11, drive 4-HA catabolism in mice. Unlike other ACADs, ACAD10 and ACAD11 feature kinase domains N-terminal to their ACAD domains that phosphorylate the 4-OH position as a requisite step in the conversion of 4-hydroxyacyl-CoAs into 2-enoyl-CoAs-conventional FAO intermediates. Our ACAD11 cryo-EM structure and molecular modeling reveal a unique binding pocket capable of accommodating this phosphorylated intermediate. We further show that ACAD10 is mitochondrial and necessary for catabolizing shorter-chain 4-HAs, whereas ACAD11 is peroxisomal and enables longer-chain 4-HA catabolism. Mice lacking ACAD11 accumulate 4-HAs in their plasma while comparable 3- and 5-hydroxy acids remain unchanged. Collectively, this work defines ACAD10 and ACAD11 as the primary gatekeepers of mammalian 4-HA catabolism and sets the stage for broader investigations into the ramifications of aberrant 4-HA metabolism in human health and disease.

6.
Angew Chem Int Ed Engl ; 63(2): e202312119, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-37996999

RESUMO

The kinetics of heterogeneous polymerization is determined directly using small-angle X-ray scattering (SAXS). This important advancement is exemplified for the synthesis of sterically-stabilized diblock copolymer nanoparticles by reversible addition-fragmentation chain transfer (RAFT) dispersion polymerization of benzyl methacrylate (BzMA) in mineral oil at 90 °C. The principle of mass balance is invoked to derive a series of equations for the analysis of the resulting time-resolved SAXS patterns. Importantly, there is a continuous change in the X-ray scattering length density for the various components within the reaction mixture. This enables the volume fraction of unreacted BzMA monomer to be calculated at any given time point, which enables the polymerization kinetics to be monitored in situ directly without relying on supplementary characterization techniques. Moreover, SAXS enables the local concentration of both monomer and solvent within the growing swollen nanoparticles to be determined during the polymerization. Data analysis reveals that the instantaneous rate of BzMA polymerization is proportional to the local monomer concentration within the nanoparticles. In principle, this powerful new time-resolved SAXS approach can be applicable to other heterogeneous polymerization formulations.

7.
bioRxiv ; 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38045259

RESUMO

Owing to its roles in cellular signal transduction, protein phosphorylation plays critical roles in myriad cell processes. That said, detecting and quantifying protein phosphorylation has remained a challenge. We describe the use of a novel mass spectrometer (Orbitrap Astral) coupled with data-independent acquisition (DIA) to achieve rapid and deep analysis of human and mouse phosphoproteomes. With this method we map approximately 30,000 unique human phosphorylation sites within a half-hour of data collection. We applied this approach to generate a phosphoproteome multi-tissue atlas of the mouse. Altogether, we detected 81,120 unique phosphorylation sites within 12 hours of measurement. With this unique dataset, we examine the sequence and structural context of protein phosphorylation. Finally, we highlight the discovery potential of this resource with multiple examples of novel phosphorylation events relevant to mitochondrial and brain biology.

8.
EJHaem ; 4(4): 1059-1070, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38024632

RESUMO

TP53 aberrations constitute the highest risk subset of myelodysplastic neoplasms (MDS) and acute myeloid leukemia (AML). The International Consensus Classification questions the blast threshold between MDS and AML. In this study, we assess the distinction between MDS and AML for 76 patients with TP53 aberrations. We observed no significant differences between MDS and AML regarding TP53 genomics. Median overall survival (OS) was 223 days for the entire group, but prognostic discrimination within subgroups showed the most inferior OS (46 days) for AML with multihit allelic state plus TP53 variant allele frequency (VAF) > 50%. In multivariate analysis, unadjusted Cox models revealed the following variables as independent risk factors for mortality: AML (vs. MDS) (hazard ratio [HR]: 2.50, confidence interval [CI]: 1.4-4.4, p = 0.001), complex karyotype (HR: 3.00, CI: 1.4-6.1, p = 0.003), multihit status (HR: 2.30, CI 1.3-4.2, p = 0.005), and absence of hematopoietic cell transplant (HCT) (HR: 3.90, CI: 1.8-8.9, p = 0.0009). Clonal dynamic modeling showed a significant reduction in TP53 VAF with front-line hypomethylating agents. These findings clarify the impact of specific covariates on outcomes of TP53-aberrant myeloid neoplasms, irrespective of the diagnosis of MDS versus AML, and may influence HCT decisions.

9.
Nat Commun ; 14(1): 6431, 2023 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-37833277

RESUMO

PPTC7 is a resident mitochondrial phosphatase essential for maintaining proper mitochondrial content and function. Newborn mice lacking Pptc7 exhibit aberrant mitochondrial protein phosphorylation, suffer from a range of metabolic defects, and fail to survive beyond one day after birth. Using an inducible knockout model, we reveal that loss of Pptc7 in adult mice causes marked reduction in mitochondrial mass and metabolic capacity with elevated hepatic triglyceride accumulation. Pptc7 knockout animals exhibit increased expression of the mitophagy receptors BNIP3 and NIX, and Pptc7-/- mouse embryonic fibroblasts (MEFs) display a major increase in mitophagy that is reversed upon deletion of these receptors. Our phosphoproteomics analyses reveal a common set of elevated phosphosites between perinatal tissues, adult liver, and MEFs, including multiple sites on BNIP3 and NIX, and our molecular studies demonstrate that PPTC7 can directly interact with and dephosphorylate these proteins. These data suggest that Pptc7 deletion causes mitochondrial dysfunction via dysregulation of several metabolic pathways and that PPTC7 may directly regulate mitophagy receptor function or stability. Overall, our work reveals a significant role for PPTC7 in the mitophagic response and furthers the growing notion that management of mitochondrial protein phosphorylation is essential for ensuring proper organelle content and function.


Assuntos
Proteínas Mitocondriais , Mitofagia , Animais , Camundongos , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Mitofagia/genética , Fibroblastos/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo
10.
Cells ; 12(18)2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37759455

RESUMO

Genome-wide association studies (GWAS) have identified a large number of genetic loci for coronary artery disease (CAD), with many located close to genes associated with traditional CAD risk pathways, such as lipid metabolism and inflammation. It is becoming evident with recent CAD GWAS meta-analyses that vascular pathways are also highly enriched and present an opportunity for novel therapeutics. This review examines GWAS-enriched vascular gene loci, the pathways involved and their potential role in CAD pathogenesis. The functionality of variants is explored from expression quantitative trait loci, massively parallel reporter assays and CRISPR-based gene-editing tools. We discuss how this research may lead to novel therapeutic tools to treat cardiovascular disorders.


Assuntos
Doenças Cardiovasculares , Doença da Artéria Coronariana , Humanos , Doença da Artéria Coronariana/metabolismo , Estudo de Associação Genômica Ampla , Locos de Características Quantitativas/genética , Doenças Cardiovasculares/genética
11.
Soft Matter ; 19(34): 6569-6577, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37603381

RESUMO

The polymorphism of lipid aggregates has long attracted detailed study due to the myriad factors that determine the final mesophase observed. This study is driven by the need to understand mesophase behaviour for a number of applications, such as drug delivery and membrane protein crystallography. In the case of the latter, the role of the so-called 'sponge' (L3) mesophase has been often noted, but not extensively studied by itself. The L3 mesophase can be formed in monoolein/water systems on the addition of butanediol to water, which partitions the headgroup region of the membrane, and decreases its elastic moduli. Like cubic mesophases, it is bicontinuous, but unlike them, has no long-range translational symmetry. In our present study, we show that the formation of the L3 phase can delicately depend on the addition of dopant lipids to the mesophase. While electrostatically neutral molecules similar in shape to monoolein (DOPE, cholesterol) have little effect on the general mesophase behaviour, others (DOPC, DDM) significantly reduce the composition at which it can form. Additionally, we show that by combining cholesterol with the anionic lipid DOPG, it is possible to form the largest stable L3 mesophases observed to date, with characteristic lengths over 220 Å.

12.
RSC Adv ; 13(29): 19662-19673, 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37396829

RESUMO

Mesoporous glasses are a promising class of bioresorbable biomaterials characterized by high surface area and extended porosity in the range of 2 to 50 nm. These peculiar properties make them ideal materials for the controlled release of therapeutic ions and molecules. Whilst mesoporous silicate-based glasses (MSG) have been widely investigated, much less work has been done on mesoporous phosphate-based glasses (MPG). In the present study, MPG in the P2O5-CaO-Na2O system, undoped and doped with 1, 3, and 5 mol% of Cu ions were synthesized via a combination of the sol-gel method and supramolecular templating. The non-ionic triblock copolymer Pluronic P123 was used as a templating agent. The porous structure was studied via a combination of Scanning Electron Microscopy (SEM), Small-Angle X-ray Scattering (SAXS), and N2 adsorption-desorption analysis at 77 K. The structure of the phosphate network was investigated via solid state 31P Magic Angle Spinning Nuclear Magnetic Resonance (31P MAS-NMR) and Fourier Transform Infrared (FTIR) spectroscopy. Degradation studies, performed in water via Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES), showed that phosphates, Ca2+, Na+ and Cu ions are released in a controlled manner over a 7 days period. The controlled release of Cu, proportional to the copper loading, imbues antibacterial properties to MPG. A significant statistical reduction of Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) bacterial viability was observed over a 3 days period. E. coli appeared to be more resistant than S. aureus to the antibacterial effect of copper. This study shows that copper doped MPG have great potential as bioresorbable materials for controlled delivery of antibacterial ions.

13.
Health Psychol Open ; 10(1): 20551029231186137, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37426943

RESUMO

Benefit finding (BF) may be a coping strategy that positively influences outcomes after a stressful event, but previous studies provide an inconsistent pattern of results across several different patient populations. This study aimed to reconcile these inconsistencies by testing whether positive affect related to a cardiac event (PA) mediates the relationship between BF and healthy dietary behaviors, and whether this mediating relationship is stronger for participants high in disease severity. Participants were patients with cardiovascular disease in a cardiac rehabilitation program. Results supported partial mediation, but the interaction was not as predicted: participants low in disease severity showed a stronger relationship between BF and PA than their counterparts high in disease severity. Additionally, the PA/healthy dietary behaviors relationship was negative. Health providers may encourage patients in CR to engage in BF, but also to make thoughtful food decisions when in a positive mood, especially for patients low in disease severity.

14.
J Pharm Pract ; : 8971900231152369, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37306306

RESUMO

Over the past two decades, emerging literature has shaped the management of pericardial syndromes and has evolved abundantly towards the creation of European guidelines for the diagnosis and management of pericardial diseases. However, since the publication of the European guidelines in 2015, more data surrounding the management of pericardial syndromes have been published. Comprehensive reference materials with the most updated literature are warranted and can be pivotal in helping pharmacists make evidence-based and clinical decisions for patients diagnosed with pericardial syndromes. This compilation of key articles and guidelines will serve as a resource for pharmacists who are responsible for the care of patients with pericardial syndromes.

15.
PLoS One ; 18(5): e0285548, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37224145

RESUMO

Laundering of textiles is a significant source of waterborne microfiber pollution, and solutions are now being sought to mitigate this issue including improvements in clothing technology and integration of filtration systems into washing machines. Vented tumble dryers are a potential source of airborne microfiber pollution, as their built-in lint filtration systems have been found to be inefficient with significant quantities of textile microfibers being released to the external environment through their exhaust air ducts. The present study is the first to evaluate the impact of condenser dryers, finding that they are significant contributors to waterborne microfiber pollution from the lint filter (if users clean this with water), the condenser and the condensed water. Microfiber release from drying of real consumer loads in condenser and vented tumble dryers was compared, finding that real loads release surprisingly high levels of microfibers (total 341.5 ± 126.0 ppm for those dried in a condenser dryer and 256.0 ± 74.2 ppm for those dried in a vented dryer), similar in quantity to microfibers produced during the first highly-shedding drying cycle of a new T-shirt load (total 321.4 ± 11.2 ppm) in a condenser dryer. Vented dryers were found to be significant contributors to waterborne microfiber pollution if consumers clean the lint filter with water in accordance with some published appliance usage instructions, as most (86.1 ± 5.5% for the real consumer loads tested) of the microfibers generated during vented tumble drying were collected on the lint filter. Therefore, tumble dryers are a significant source of waterborne and (for vented dryers) airborne microfiber pollution. While reducing the pore size of tumble dryer lint filters and instructing consumers to dispose of fibers collected on lint filters as municipal solid waste could help reduce the issue, more sophisticated engineering solutions will likely be required to achieve a more comprehensive solution.


Assuntos
Dessecação , Poluição Ambiental , Engenharia , Resíduos Sólidos , Água
18.
Nat Commun ; 14(1): 215, 2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36639380

RESUMO

A common feature of glasses is the "boson peak", observed as an excess in the heat capacity over the crystal or as an additional peak in the terahertz vibrational spectrum. The microscopic origins of this peak are not well understood; the emergence of locally ordered structures has been put forward as a possible candidate. Here, we show that depolarised Raman scattering in liquids consisting of highly symmetric molecules can be used to isolate the boson peak, allowing its detailed observation from the liquid into the glass. The boson peak in the vibrational spectrum matches the excess heat capacity. As the boson peak intensifies on cooling, wide-angle x-ray scattering shows the simultaneous appearance of a pre-peak due to molecular clusters consisting of circa 20 molecules. Atomistic molecular dynamics simulations indicate that these are caused by over-coordinated molecules. These findings represent an essential step toward our understanding of the physics of vitrification.

19.
Br J Clin Pharmacol ; 89(3): 1207-1210, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36367379

RESUMO

The goal of this study was to use a model kidney function clearance-dependent drug (vancomycin) to understand the gain or loss of precision in dosing with use of serum creatinine (Scr ), serum cystatin C (Scys ) and race and nonrace-based equations of the estimated glomerular filtration rate (eGFR). In this study of hospitalized patients, we compared Scr , Scys and their combination to estimate kidney function and vancomycin clearance. The nonrace-based Scys eGFR model outperformed other clearance models and improved the probability of target attainment by 15%. When Scys is not available, we show that the new 2021 CKD-EPI eGFRcr equation (no race factor) performs as well as the current conventional approach. This improvement in model performance does not negate the need for individualized dosing but exemplifies the need to remove race as a factor of kidney-function dose adjustment.


Assuntos
Insuficiência Renal Crônica , Vancomicina , Humanos , Taxa de Filtração Glomerular , Creatinina , Cistatina C
20.
Psychol Serv ; 20(1): 19-29, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36355661

RESUMO

Studies of moral injury among nonmilitary samples are scarce despite repeated calls to examine the prevalence and outcomes of moral injury among civilian frontline workers. The purpose of this study was to describe the prevalence of moral injury and to examine its association with psychosocial functioning among health care workers during the COVID-19 pandemic. We surveyed health care workers (N = 480), assessing exposure to potentially morally injurious events (PMIEs) and psychosocial functioning. Data were analyzed using latent class analysis (LCA) to explore patterns of PMIE exposure (i.e., classes) and corresponding psychosocial functioning. The minimal exposure class, who denied PMIE exposure, accounted for 22% of health care workers. The moral injury-other class included those who had witnessed PMIEs for which others were responsible and felt betrayed (26%). The moral injury-self class comprised those who felt they transgressed their own values in addition to witnessing others' transgressions and feeling betrayed (11%). The betrayal-only class included those who felt betrayed by government and community members but otherwise denied PMIE exposure (41%). Those assigned to the moral injury-self class were the most impaired on a psychosocial functioning composite, followed by those assigned to the moral injury-other and betrayal-only classes, and finally the minimal exposure class. Moral injury is prevalent and impairing for health care workers, which establishes a need for interventions with health care workers in organized care settings. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
COVID-19 , Transtornos de Estresse Pós-Traumáticos , Humanos , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Transtornos de Estresse Pós-Traumáticos/psicologia , COVID-19/epidemiologia , Pandemias , Funcionamento Psicossocial , Pessoal de Saúde/psicologia
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