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1.
ACS Mater Lett ; 6(5): 1863-1869, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38726043

RESUMO

The use of sustainable and safe materials is increasingly in demand for the creation of photonic-based technology. Piezoelectric peptide nanotubes make up a class of safe and sustainable materials. We show that these materials can generate piezoelectric charge through the deformation of oriented molecular dipoles when the tube length is flexed through the application of sound energy. Through the combination of peptide nanotubes with plasmon active nanomaterials, harvesting of low-frequency acoustic sound waves was achieved. This effect was applied to boost surface-enhanced Raman scattering signal detection of analytes, including glucose. This work demonstrates the potential of utilizing sound to boost sensing by using piezoelectric materials.

2.
Phys Chem Chem Phys ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38747528

RESUMO

Organosilanes are commonly utilized to attach bioreceptors to oxide surfaces. The deposition of such silane layers is especially challenging in nanoscale or nanoconfined devices, such as in nanopipettes, since rinsing off loosely bound silanes may not be possible due to geometric constrictions and because the thickness of multilayered silanes can cover or block nanoscale features. Furthermore, in electrochemical devices, the silane layers experience additional perturbations, such as electric migration and electroosmotic force. Despite its importance, there appears to be no consensus in the current literature on the optimal methodology for nanopipette silanization, with significant variations in reported conditions. Herein, we systematically investigate the reproducibility and stability of liquid- and vapor-phase deposited silane layers inside nanopipettes. Electrochemical monitoring of the changing internal silanized surface reveals that vapor-deposited APTES generates surface modifications with the highest reproducibility, while vapor-deposited APTMS generates surface modifications of the highest stability over a 24-hour time period. Practical issues of silanizing nanoconfined systems are highlighted, and the importance of carefully chosen silanization conditions to yield stable and reproducible monolayers is emphasized as an underappreciated aspect in the development of novel nanoscale systems.

3.
Nat Struct Mol Biol ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38720088

RESUMO

Rev1-Polζ-dependent translesion synthesis (TLS) of DNA is crucial for maintaining genome integrity. To elucidate the mechanism by which the two polymerases cooperate in TLS, we determined the cryogenic electron microscopic structure of the Saccharomyces cerevisiae Rev1-Polζ holocomplex in the act of DNA synthesis (3.53 Å). We discovered that a composite N-helix-BRCT module in Rev1 is the keystone of Rev1-Polζ cooperativity, interacting directly with the DNA template-primer and with the Rev3 catalytic subunit of Polζ. The module is positioned akin to the polymerase-associated domain in Y-family TLS polymerases and is set ideally to interact with PCNA. We delineate the full extent of interactions that the carboxy-terminal domain of Rev1 makes with Polζ and identify potential new druggable sites to suppress chemoresistance from first-line chemotherapeutics. Collectively, our results provide fundamental new insights into the mechanism of cooperativity between Rev1 and Polζ in TLS.

4.
Phys Med Biol ; 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38657632

RESUMO

Six decades after its conception, proton computed tomography (pCT) and proton radiography have yet to be used in medical clinics. However, good progress has been made on relevant detector technologies in the past two decades, and a few prototype pCT systems now exist that approach the performance needed for a clinical device. The tracking and energy-measurement technologies in common use are described, as are the few pCT scanners that are in routine operation at this time. Most of these devices still look like detector R\&D efforts as opposed to medical devices, are difficult to use, are at least factor of five slower than desired for clinical use, and are too small to image many parts of the human body. Recommendations are made for what to consider when engineering a pre-clinical pCT scanner that is designed to meet clinical needs in terms of performance, cost, and ease of use.

5.
Anal Chem ; 96(15): 6055-6064, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38569051

RESUMO

While ion current rectification (ICR) in aprotic solvent has been fundamentally studied, its application in sensing devices lacks exploration. The development of sensors operable in these solvents is highly beneficial to the chemical industry, where polar aprotic solvents, such as acetonitrile, are widely used. Currently, this industry relies on the use of inductively coupled plasma mass spectrometry (ICP-MS) and optical emission spectroscopy (OES) for the detection of metal contamination in organic products. Herein, we present the detection of trace amounts of Pd2+ and Co2+ using ion current rectification, in cyclam-functionalized quartz nanopipettes, with tetraethylammonium tetrafluoroborate (TEATFB) in MeCN as supporting electrolyte. This methodology is employed to determine the concentration of Pd in organic products, before and after purification by Celite filtration and column chromatography, obtaining comparable results to ICP-MS within minutes and without complex sample preparation. Finite element simulations are used to support our experimental findings, which reveal that the formation of double-junction diodes in the nanopore enables trace detection of these metals, with a significant response from baseline even at picomolar concentrations.

6.
Chem Sci ; 15(11): 3879-3892, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38487227

RESUMO

Accelerated SuFEx Click Chemistry (ASCC) is a powerful method for coupling aryl and alkyl alcohols with SuFEx-compatible functional groups. With its hallmark favorable kinetics and exceptional product yields, ASCC streamlines the synthetic workflow, simplifies the purification process, and is ideally suited for discovering functional molecules. We showcase the versatility and practicality of the ASCC reaction as a tool for the late-stage derivatization of bioactive molecules and in the array synthesis of sulfonate-linked, high-potency, microtubule targeting agents (MTAs) that exhibit nanomolar anticancer activity against multidrug-resistant cancer cell lines. These findings underscore ASCC's promise as a robust platform for drug discovery.

7.
Br J Gen Pract ; 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38499295

RESUMO

BACKGROUND: Herpes zoster (shingles) is normally diagnosed clinically. Timely diagnosis is important so antiviral treatment can be started soon after rash onset. AIM: To assess whether a practice-level educational intervention, aimed at non-clinical patient-facing staff, improves the timely assessment of patients with shingles. DESIGN AND SETTING: Cluster randomised Study Within A Trial (SWAT) with nested qualitative study in General Practices in England. METHODS: Practices were cluster randomised 1:1, stratified by centre and minimised by practice list size and index of multiple deprivation score. Intervention practices were sent educational materials, highlighting the common presenting features of shingles and what action to take if suspected. The primary and secondary outcomes were the mean proportion of patients per practice seen within 72 hours and 144 of rash onset, respectively. Comparison between groups was conducted using linear regression, adjusting for randomisation variables. Semi-structured interviews with practice staff in intervention practices explored views and opinions of the intervention. RESULTS: 67 practices were enrolled; 34 randomised to intervention, 33 to control. The mean difference in proportion of patients seen within 72 and 144 hours was -0.132 (95% CI -0.308, 0.043) and -0.039 (95% CI -0.158, 0.080), respectively. In intervention practices, 90.5% reported distributing the educational materials, however engagement with these was suboptimal. 12 participants were interviewed, and the poster component of the intervention was said to be easiest to implement. CONCLUSION: Our educational intervention did not improve the timely assessment of patients with shingles. This may be the result of poor intervention engagement.

8.
Sci Data ; 11(1): 215, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38365981

RESUMO

Biological ocean data collected from ships find reuse in aggregations of historical data. These data are heavily relied upon to document long term change, validate satellite algorithms for ocean biology and are useful in assessing the performance of autonomous platforms and biogeochemical models. Existing aggregate products have largely been restricted to the surface ocean, omit physical data or have limited biological data. We present the first version of a BIOlogical ocean data reforMATting Effort (BIO-MATE) to begin to fill a gap in subsurface bio-physical data aggregates in a reproducible way. BIO-MATE uses open-source R software that reformats openly sourced published datasets from oceanographic voyages. These reformatted biological and physical data from underway sensors, profiling sensors, pigments analysis and particulate organic carbon analysis are stored in an interoperable BIO-MATE data product for easy access and use. Specific QA/QC protocols can now be easily applied to the BIO-MATE data product to support a variety of surface and subsurface applications.


Assuntos
Oceanos e Mares , Software
9.
Clin Infect Dis ; 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38356144

RESUMO

COVID-19 epidemiology and product landscapes have changed considerably since onset of the pandemic. Safe and effective vaccines and therapeutics are available, but the continual emergence of SARS-CoV-2 variants introduce limitations in our ability to prevent and treat disease. Project NextGen is a collaboration between the Biomedical Advanced Research and Development Authority (BARDA), part of the Administration for Strategic Preparedness and Response (ASPR), and the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, that is leveraging public-private partnerships to address gaps in the nation's COVID-19 vaccine and therapeutic capabilities. Targeted investments will advance promising next-generation candidates through the most difficult phases of clinical development to encourage further private sector interest for later stage development and commercial availability. New commercial vaccines and therapeutics that are more durable and effective across variants will improve our fight against COVID-19 and transform our response to future threats.

10.
J Infect Dis ; 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38244206

RESUMO

Infectious disease outbreaks have become increasingly common and require global partnership for adequate preparedness and response. During outbreaks, medical countermeasures (MCMs)-vaccines, therapeutics, and diagnostics-need to reach patients quickly. BARDA utilizes public-private partnerships to support advanced development of MCMs through U.S. FDA approval against a variety of threats within its mission space. MCM preparedness and response must be approached as an integrated life cycle, not as independent steps. Recent filovirus outbreaks in Africa exemplify that collaborative relationships are critical for emergency response, and products with regulatory approval can expand access and reach patients quicker than investigational products. Unfortunately, insufficient funding globally and differences in funders' prioritization puts gains and future efforts at risk. Of primary concern is a) lack of a feasible regulatory path and clinical capability to achieve regulatory approval for new MCMs for many diseases; and b) the need for partners with the mandate, funding, and capabilities to support the life cycle activities following development-long-term sustainment of manufacturing capability and stockpiling of licensed products to support international outbreaks. Finding partners that complement BARDA's mission and support the MCM life cycle will be a key component in deciding which MCM development efforts can be supported. Without collaboration, the global community runs the risk of losing the capabilities built through years of investment and being underprepared to combat future threats. Synergies between funders that have different roles and responsibilities within the MCM life cycle are critical to MCM availability and create long-term sustainment of products to ensure access.

11.
Clin Teach ; : e13725, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38233356

RESUMO

Capability is the ability to perform clinical skills in ever-changing real world contexts, adapting to challenges and integrating technical and non-technical skills and competencies, for example, cannulating an uncooperative patient at night. Going beyond teaching competency and ensuring capability is imperative, as recommended by the national outcomes for medical graduates. A course on intravenous cannulation was developed with e-learning modules and high-fidelity complex simulation scenarios, aiming to promote capability in practice. The course delivered an intravenous cannulation e-learning package between two practical simulations to 10 final-year medical students. The hybrid simulation design consisted of an actor with a bespoke cannulation part-task trainer strapped to their arm. Each simulation delivered a challenging scenario, requiring the integration of procedural and behavioural skills to succeed. Simulations were video recorded, and participants reviewed their performances before completing semi-structured interviews. Transcribed interviews were thematically analysed. Interview analysis demonstrated two overarching themes: 'Impact on Capability' and 'Preparedness for Practice'. There was consistent recognition of improved capability from the interviews. Simulation exercises were described as the most valuable tool for developing capability. The e-learning helped with structure, facilitating students' adaptation to scenarios. Participants felt that training in medical school was largely competency-based and did not tackle complex interactions. Following e-learning and simulations, students felt more prepared for clinical practice. The course structure has value for medical professionals in developing capability and preparing for clinical practice, helping to reach standards expected of graduates. Plans to assess capability across multiple undergraduate programmes through Entrustable Professional Activities are in progress.

12.
Br J Pharmacol ; 2023 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-38044463

RESUMO

BACKGROUND AND PURPOSE: Decreased aortic compliance is a precursor to numerous cardiovascular diseases. Compliance is regulated by the rigidity of the aortic wall and the vascular smooth muscle cells (VSMCs). Extracellular matrix stiffening, observed during ageing, reduces compliance. In response to increased rigidity, VSMCs generate enhanced contractile forces that result in VSMC stiffening and a further reduction in compliance. Mechanisms driving VSMC response to matrix rigidity remain poorly defined. EXPERIMENTAL APPROACH: Human aortic-VSMCs were seeded onto polyacrylamide hydrogels whose rigidity mimicked either healthy (12 kPa) or aged/diseased (72 kPa) aortae. VSMCs were treated with pharmacological agents prior to agonist stimulation to identify regulators of VSMC volume regulation. KEY RESULTS: On pliable matrices, VSMCs contracted and decreased in cell area. Meanwhile, on rigid matrices VSMCs displayed a hypertrophic-like response, increasing in area and volume. Piezo1 activation stimulated increased VSMC volume by promoting calcium ion influx and subsequent activation of PKC and aquaporin-1. Pharmacological blockade of this pathway prevented the enhanced VSMC volume response on rigid matrices whilst maintaining contractility on pliable matrices. Importantly, both piezo1 and aquaporin-1 gene expression were up-regulated during VSMC phenotypic modulation in atherosclerosis and after carotid ligation. CONCLUSIONS AND IMPLICATIONS: In response to extracellular matrix rigidity, VSMC volume is increased by a piezo1/PKC/aquaporin-1 mediated pathway. Pharmacological targeting of this pathway specifically blocks the matrix rigidity enhanced VSMC volume response, leaving VSMC contractility on healthy mimicking matrices intact. Importantly, upregulation of both piezo1 and aquaporin-1 gene expression is observed in disease relevant VSMC phenotypes.

13.
J Virol ; 97(11): e0133623, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37846985

RESUMO

IMPORTANCE: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has caused a wide spectrum of diseases in the human population, from asymptomatic infections to death. It is important to study the host differences that may alter the pathogenesis of this virus. One clinical finding in coronavirus disease 2019 (COVID-19) patients is that people with obesity or diabetes are at increased risk of severe illness from SARS-CoV-2 infection. We used a high-fat diet model in mice to study the effects of obesity and type 2 diabetes on SARS-CoV-2 infection as well as how these comorbidities alter the response to vaccination. We find that diabetic/obese mice have increased disease after SARS-CoV-2 infection and they have slower clearance of the virus. We find that the lungs of these mice have increased neutrophils and that removing these neutrophils protects diabetic/obese mice from disease. This demonstrates why these diseases have increased risk of severe disease and suggests specific interventions upon infection.


Assuntos
Vacinas contra COVID-19 , Diabetes Mellitus Tipo 2 , Obesidade , Eficácia de Vacinas , Animais , Humanos , Camundongos , COVID-19/prevenção & controle , Diabetes Mellitus Tipo 2/complicações , Dieta , Camundongos Obesos , Obesidade/complicações , SARS-CoV-2 , Vacinas contra COVID-19/administração & dosagem
16.
Cell Mol Life Sci ; 80(9): 276, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37668685

RESUMO

Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) have the potential to remuscularize infarcted hearts but their arrhythmogenicity remains an obstacle to safe transplantation. Myofibroblasts are the predominant cell-type in the infarcted myocardium but their impact on transplanted hiPSC-CMs remains poorly defined. Here, we investigate the effect of myofibroblasts on hiPSC-CMs electrophysiology and Ca2+ handling using optical mapping of advanced human cell coculture systems mimicking cell-cell interaction modalities. Human myofibroblasts altered the electrophysiology and Ca2+ handling of hiPSC-CMs and downregulated mRNAs encoding voltage channels (KV4.3, KV11.1 and Kir6.2) and SERCA2a calcium pump. Interleukin-6 was elevated in the presence of myofibroblasts and direct stimulation of hiPSC-CMs with exogenous interleukin-6 recapitulated the paracrine effects of myofibroblasts. Blocking interleukin-6 reduced the effects of myofibroblasts only in the absence of physical contact between cell-types. Myofibroblast-specific connexin43 knockdown reduced functional changes in contact cocultures only when combined with interleukin-6 blockade. This provides the first in-depth investigation into how human myofibroblasts modulate hiPSC-CMs function, identifying interleukin-6 and connexin43 as paracrine- and contact-mediators respectively, and highlighting their potential as targets for reducing arrhythmic risk in cardiac cell therapy.


Assuntos
Células-Tronco Pluripotentes Induzidas , Miócitos Cardíacos , Humanos , Miofibroblastos , Conexina 43/genética , Interleucina-6/genética , Arritmias Cardíacas/genética , Cardiotônicos
17.
Life Sci Alliance ; 6(10)2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37550007

RESUMO

Tunneling nanotubes (TNTs) are thin cytoplasmic extensions involved in long-distance intercellular communication and can transport intracellular organelles and signalling molecules. In cancer cells, TNT formation contributes to cell survival, chemoresistance, and malignancy. However, the molecular mechanisms underlying TNT formation are not well defined, especially in different cancers. TNTs are present in non-small cell lung cancer (NSCLC) patients with adenocarcinoma. In NSCLC, hepatocyte growth factor (HGF) and its receptor, c-Met, are mutationally upregulated, causing increased cancer cell growth, survival, and invasion. This study identifies c-Met, ß1-integrin, and paxillin as novel components of TNTs in A549 lung adenocarcinoma cells, with paxillin localised at the protrusion site of TNTs. The HGF-induced TNTs in our study demonstrate the ability to transport lipid vesicles and mitochondria. HGF-induced TNT formation is mediated by c-Met and ß1-integrin in conjunction with paxillin, followed by downstream activation of MAPK and PI3K pathways and the Arp2/3 complex. These findings demonstrate a potential novel approach to inhibit TNT formation through targeting HGF/c-Met receptor and ß1-integrin signalling interactions, which has implications for multi-drug targeting in NSCLC.


Assuntos
Adenocarcinoma de Pulmão , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Paxilina , Fosfatidilinositol 3-Quinases , Integrinas , Fator de Crescimento de Hepatócito
18.
mBio ; 14(5): e0158723, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37581442

RESUMO

IMPORTANCE: Pyronaridine tetraphosphate is on the WHO Essential Medicine List for its importance as a widely available and safe treatment for malaria. We find that pyronaridine is a highly effective antiviral therapeutic across mouse models using multiple variants of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), and the highly pathogenic viruses SARS-CoV-1 and Middle East respiratory syndrome coronavirus responsible for previous coronavirus outbreaks. Additionally, we find that pyronaridine additively combines with current COVID-19 treatments such as nirmatrelvir (protease inhibitor in Paxlovid) and molnupiravir to further inhibit SARS-CoV-2 infections. There are many antiviral compounds that demonstrate efficacy in cellular models, but few that show this level of impact in multiple mouse models and represent a promising therapeutic for the current coronavirus pandemic as well as future outbreaks as well.


Assuntos
COVID-19 , Coronavírus da Síndrome Respiratória do Oriente Médio , Camundongos , Animais , Antivirais/farmacologia , Antivirais/uso terapêutico , Naftiridinas/farmacologia , SARS-CoV-2
19.
Toxicol Sci ; 196(1): 112-125, 2023 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-37647630

RESUMO

To minimize the occurrence of unexpected toxicities in early phase preclinical studies of new drugs, it is vital to understand fundamental similarities and differences between preclinical species and humans. Species differences in sensitivity to acetaminophen (APAP) liver injury have been related to differences in the fraction of the drug that is bioactivated to the reactive metabolite N-acetyl-p-benzoquinoneimine (NAPQI). We have used physiologically based pharmacokinetic modeling to identify oral doses of APAP (300 and 1000 mg/kg in mice and rats, respectively) yielding similar hepatic burdens of NAPQI to enable the comparison of temporal liver tissue responses under conditions of equivalent chemical insult. Despite pharmacokinetic and biochemical verification of the equivalent NAPQI insult, serum biomarker and tissue histopathology analyses revealed that mice still exhibited a greater degree of liver injury than rats. Transcriptomic and proteomic analyses highlighted the stronger activation of stress response pathways (including the Nrf2 oxidative stress response and autophagy) in the livers of rats, indicative of a more robust transcriptional adaptation to the equivalent insult. Components of these pathways were also found to be expressed at a higher basal level in the livers of rats compared with both mice and humans. Our findings exemplify a systems approach to understanding differential species sensitivity to hepatotoxicity. Multiomics analysis indicated that rats possess a greater basal and adaptive capacity for hepatic stress responses than mice and humans, with important implications for species selection and human translation in the safety testing of new drug candidates associated with reactive metabolite formation.


Assuntos
Acetaminofen , Doença Hepática Induzida por Substâncias e Drogas , Ratos , Camundongos , Humanos , Animais , Acetaminofen/toxicidade , Acetaminofen/metabolismo , Proteômica , Especificidade da Espécie , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Fígado/metabolismo , Estresse Oxidativo , Análise de Sistemas
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