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1.
Nature ; 631(8021): 544-548, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39020036

RESUMO

A long-standing challenge is how to formulate proteins and vaccines to retain function during storage and transport and to remove the burdens of cold-chain management. Any solution must be practical to use, with the protein being released or applied using clinically relevant triggers. Advanced biologic therapies are distributed cold, using substantial energy, limiting equitable distribution in low-resource countries and placing responsibility on the user for correct storage and handling. Cold-chain management is the best solution at present for protein transport but requires substantial infrastructure and energy. For example, in research laboratories, a single freezer at -80 °C consumes as much energy per day as a small household1. Of biological (protein or cell) therapies and all vaccines, 75% require cold-chain management; the cost of cold-chain management in clinical trials has increased by about 20% since 2015, reflecting this complexity. Bespoke formulations and excipients are now required, with trehalose2, sucrose or polymers3 widely used, which stabilize proteins by replacing surface water molecules and thereby make denaturation thermodynamically less likely; this has enabled both freeze-dried proteins and frozen proteins. For example, the human papilloma virus vaccine requires aluminium salt adjuvants to function, but these render it unstable against freeze-thaw4, leading to a very complex and expensive supply chain. Other ideas involve ensilication5 and chemical modification of proteins6. In short, protein stabilization is a challenge with no universal solution7,8. Here we designed a stiff hydrogel that stabilizes proteins against thermal denaturation even at 50 °C, and that can, unlike present technologies, deliver pure, excipient-free protein by mechanically releasing it from a syringe. Macromolecules can be loaded at up to 10 wt% without affecting the mechanism of release. This unique stabilization and excipient-free release synergy offers a practical, scalable and versatile solution to enable the low-cost, cold-chain-free and equitable delivery of therapies worldwide.


Assuntos
Armazenamento de Medicamentos , Hidrogéis , Desnaturação Proteica , Estabilidade Proteica , Proteínas , Seringas , Humanos , Excipientes , Liofilização , Hidrogéis/química , Proteínas/administração & dosagem , Proteínas/química , Proteínas/economia , Trealose , Congelamento , Refrigeração , Vacinas contra Papillomavirus/química , Armazenamento de Medicamentos/economia , Armazenamento de Medicamentos/métodos
2.
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.

3.
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.

4.
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.

5.
Front Health Serv ; 4: 1326777, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39036464

RESUMO

Background: Rural healthcare has unique characteristics that affect the dissemination and implementation of evidence-based interventions. Numerous theories, models, and frameworks have been developed to guide implementation of healthcare interventions, though not specific to rural healthcare. The present scoping review sought to identify the theories, models, and frameworks most frequently applied to rural health and propose an approach to rural health research that harnesses selected constructs from these theories, models, and frameworks. This resulting synthesis can serve as a guide to researchers, policy makers, and clinicians seeking to employ commonly used theories, models, and frameworks to rural health. Methods: We used the Scopus abstract indexing service to identify peer-reviewed literature citing one or more of theories, models, or frameworks used in dissemination and implementation research and including the word "rural" in the Title, Abstract, or Keywords. We screened the remaining titles and abstracts to ensure articles met additional inclusion criteria. We conducted a full review of the resulting 172 articles to ensure they identified one or more discrete theory, model, or framework applied to research or quality improvement projects. We extracted the theories, models, and frameworks and categorized these as process models, determinant frameworks, classic theories, or evaluation frameworks. Results: We retained 61 articles of which 28 used RE-AIM, 11 used Community-Based Participatory Research (CBPR) framework, eight used the Consolidated Framework for Implementation Research (CFIR), and six used the integrated-Promoting Action on Research Implementation in Health Services (iPARIHS). Additional theories, models, and frameworks were cited in three or fewer reports in the literature. The 14 theories, models, and frameworks cited in the literature were categorized as seven process models, four determinant frameworks, one evaluation framework, and one classic theory. Conclusions: The RE-AIM framework was the most frequently cited framework in the rural health literature, followed by CBPR, CFIR, and iPARIHS. A notable advantage of RE-AIM in rural healthcare settings is the focus on reach as a specified outcome, given the challenges of engaging a geographically diffuse and often isolated population. We present a rationale for combining the strengths of these theories, models, and frameworks to guide a research agenda specific to rural healthcare research. Systematic Review Registration: https://osf.io/fn2cd/.

6.
Chem Sci ; 15(30): 11825-11836, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39092096

RESUMO

Harnessing flexible host cavities opens opportunities for the design of novel supramolecular architectures that accommodate nanosized guests. This research examines unprecedented gas-phase structures of Keggin-type polyoxometalate PW12O40 3- (WPOM) and cyclodextrins (X-CD, X = α, ß, γ, δ, ε, ζ) including previously unexplored large, flexible CDs. Using ion mobility spectrometry coupled to mass spectrometry (IM-MS) in conjunction with molecular dynamics (MD) simulations, we provide first insights into the binding modes between WPOM and larger CD hosts as isolated structures. Notably, γ-CD forms two distinct structures with WPOM through binding to its primary and secondary faces. We also demonstrate that ε-CD forms a deep inclusion complex, which encapsulates WPOM within its annular inner cavity. In contrast, ζ-CD adopts a saddle-like conformation in its complex with WPOM, which resembles its free form in solution. More intriguingly, the gas-phase CD-WPOM structures are highly correlated with their counterparts in solution as characterized by nuclear magnetic resonance (NMR) spectroscopy. The strong correlation between the gas- and solution phase structures of CD-WPOM complexes highlight the power of gas-phase IM-MS for the structural characterization of supramolecular complexes with nanosized guests, which may be difficult to examine using conventional approaches.

7.
FEBS Open Bio ; 14(8): 1222-1229, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38877345

RESUMO

Methyl-coenzyme M reductase (MCR) is a multi-subunit (α2ß2γ2) enzyme responsible for methane formation via its unique F430 cofactor. The genes responsible for producing MCR (mcrA, mcrB and mcrG) are typically colocated with two other highly conserved genes mcrC and mcrD. We present here the high-resolution crystal structure for McrD from a human gut methanogen Methanomassiliicoccus luminyensis strain B10. The structure reveals that McrD comprises a ferredoxin-like domain assembled into an α + ß barrel-like dimer with conformational flexibility exhibited by a functional loop. The description of the M. luminyensis McrD crystal structure contributes to our understanding of this key conserved methanogen protein typically responsible for promoting MCR activity and the production of methane, a greenhouse gas.


Assuntos
Oxirredutases , Oxirredutases/metabolismo , Oxirredutases/química , Oxirredutases/genética , Cristalografia por Raios X , Modelos Moleculares , Metano/metabolismo , Metano/química , Humanos , Conformação Proteica , Proteínas Arqueais/metabolismo , Proteínas Arqueais/química , Proteínas Arqueais/genética
8.
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
9.
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.

10.
Matrix Biol ; 132: 34-46, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38925225

RESUMO

Cardiac fibroblasts are pivotal regulators of cardiac homeostasis and are essential in the repair of the heart after myocardial infarction (MI), but their function can also become dysregulated, leading to adverse cardiac remodelling involving both fibrosis and hypertrophy. MicroRNAs (miRNAs) are noncoding RNAs that target mRNAs to prevent their translation, with specific miRNAs showing differential expression and regulation in cardiovascular disease. Here, we show that miR-214-3p is enriched in the fibroblast fraction of the murine heart, and its levels are increased with cardiac remodelling associated with heart failure, or in the acute phase after experimental MI. Tandem mass tagging proteomics and in-silico network analyses were used to explore protein targets regulated by miR-214-3p in cultured human cardiac fibroblasts from multiple donors. Overexpression of miR-214-3p by miRNA mimics resulted in decreased expression and activity of the Piezo1 mechanosensitive cation channel, increased expression of the entire lysyl oxidase (LOX) family of collagen cross-linking enzymes, and decreased expression of an array of mitochondrial proteins, including mitofusin-2 (MFN2), resulting in mitochondrial dysfunction, as measured by citrate synthase and Seahorse mitochondrial respiration assays. Collectively, our data suggest that miR-214-3p is an important regulator of cardiac fibroblast phenotypes and functions key to cardiac remodelling, and that this miRNA represents a potential therapeutic target in cardiovascular disease.


Assuntos
Fibroblastos , Canais Iônicos , MicroRNAs , MicroRNAs/genética , MicroRNAs/metabolismo , Humanos , Fibroblastos/metabolismo , Animais , Camundongos , Canais Iônicos/metabolismo , Canais Iônicos/genética , Regulação da Expressão Gênica , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/genética , Infarto do Miocárdio/patologia , Miocárdio/metabolismo , Miocárdio/citologia , Miocárdio/patologia , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/patologia , Mitocôndrias/metabolismo , Mitocôndrias/genética , Células Cultivadas
11.
Nat Commun ; 15(1): 7016, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39147754

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. The technology is benchmarked to other state-of-the-art MS platforms using both synthetic peptide standards and with EGF-stimulated HeLa cells. We apply this approach to generate a phosphoproteome multi-tissue atlas of the mouse. Altogether, we detect 81,120 unique phosphorylation sites within 12 hours of measurement. With this unique dataset, we examine the sequence, structural, and kinase specificity context of protein phosphorylation. Finally, we highlight the discovery potential of this resource with multiple examples of phosphorylation events relevant to mitochondrial and brain biology.


Assuntos
Espectrometria de Massas , Fosfoproteínas , Proteoma , Proteômica , Humanos , Fosfoproteínas/metabolismo , Fosfoproteínas/análise , Animais , Células HeLa , Fosforilação , Camundongos , Proteoma/metabolismo , Espectrometria de Massas/métodos , Proteômica/métodos
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