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1.
J Environ Sci (China) ; 149: 651-662, 2025 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-39181675

RESUMO

Fischer-Tropsch synthesis (FTS) wastewater retaining low-carbon alcohols and acids are organic pollutants as a limiting factor for FTS industrialization. In this work, the structure-capacity relationships between alcohol-acid adsorption and surface species on graphene were reported, shedding light into their intricate interactions. The graphene oxide (GO) and reduced graphene oxide (rGO) were synthesized via improved Hummers method with flake graphite (G). The physicochemical properties of samples were characterized via SEM, XRD, XPS, FT-IR, and Raman. The alcohol-acid adsorption behaviors and adsorption quantities on G, GO, and rGO were measured via theoretical and experimental method. It was revealed that the presence of COOH, C=O and CO species on graphene occupy the adsorption sites and increase the interactions of water with graphene, which are unfavorable for alcohol-acid adsorption. The equilibrium adsorption quantities of alcohols and acids grow in pace with carbon number. The monolayer adsorption occurs on graphene was verified via model fitting. rGO has the highest FTS modeling wastewater adsorption quantity (110 mg/g) due to the reduction of oxygen species. These novel findings provide a foundation for the alcohol-acid wastewater treatment, as well as the design and development of high-performance carbon-based adsorbent materials.


Assuntos
Álcoois , Grafite , Águas Residuárias , Poluentes Químicos da Água , Grafite/química , Adsorção , Águas Residuárias/química , Poluentes Químicos da Água/química , Álcoois/química , Eliminação de Resíduos Líquidos/métodos , Modelos Químicos , Ácidos/química
2.
Front Chem ; 12: 1442824, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39091278

RESUMO

In this study, a trisodium citrate (TSC)-assisted hydrothermal method is utilized to prepare three-dimensional hydroxyapatite (3D HA). Understanding the role of TSC in the preparation of 3D HA crystals may provide valuable methods to design advanced biomaterials. As one of the indexes of solution supersaturation, the initial pH (ipH) value can not only directly affect the nucleation rate, but also affect the growth of HA crystals. In this work, the effect of the ipH on the microstructure, particle size distribution, and specific surface area of the 3D HA is explored. Results showed that the morphology of 3D HA transformed from a bundle to a dumbbell ball and then a dumbbell with an increase in the ipH. A corresponding mechanism of such a structural evolution was proposed, providing inspiration for the fabrication of innovative 3D HA structures with enhanced biological functionality and performance.

3.
Angew Chem Int Ed Engl ; : e202411889, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39086010

RESUMO

The stereochemistry of shape-persistent molecular cages, particularly those resembling prisms, exerts significant influence on their application-specific functionalities. Although methods exist for fabricating inherently chiral prism-like cages, strategies for catalytic asymmetric synthesis of these structures in a diversity-oriented fashion remain unexplored. Herein, we introduce an unprecedented organocatalytic desymmetrization approach for the generation of inherently chiral prism-like cages via phosphonium-containing foldamer-catalyzed SNAr reactions. This methodology establishes a topological connection, enabling the facile assembly of a wide range of versatile stereogenic-at-cage building blocks possessing two highly modifiable groups. Furthermore, subsequent stereospecific transformations of the remaining chlorides and/or ethers afford convenient access to numerous functionally relevant chiral-at-cage molecules.

4.
Angew Chem Int Ed Engl ; : e202410579, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39086115

RESUMO

Within living organisms, numerous nanomachines are constantly involved in complex polymerization processes, generating a diverse array of biomacromolecules for maintaining biological activities. Transporting artificial polymerizations from lab settings into biological contexts has expanded opportunities for understanding and managing biological events, creating novel cellular compartments, and introducing new functionalities. This review summarizes the recent advancements in artificial polymerizations, including those responding to external stimuli, internal environmental factors, and those that polymerize spontaneously. More importantly, the cutting-edge biomedical application scenarios of artificial polymerization, notably in safeguarding cells, modulating biological events, improving diagnostic performance, and facilitating therapeutic efficacy are highlighted. Finally, this review outlines the key challenges and technological obstacles that remain for polymerizations in biological organisms, as well as offers insights into potential directions for advancing their practical applications and clinical trials.

5.
Adv Healthc Mater ; : e2401513, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39091058

RESUMO

Carbon dots (CDs) with good optical properties, biocompatibility, easy functionalization, and small size have attracted more and more attention and laid a good foundation for their applications in the biomedicine field. CDs emitted in near-infrared regions (NIR-CDs) can achieve high penetration depth imaging and produce high cytotoxic substance for disease treatment. Therefore, NIR-CDs are promising materials to realize high-quality imaging-guided diagnostic and therapeutic integration. This review first introduces the current mainstream synthesis methods of NIR-CDs by "top-down" and "bottom-up". Second, the luminescence modes of NIR-CDs are introduced, and the luminescence mechanisms based on carbon core state, surface state, molecular state, and crosslinking enhanced emission are summarized. Third, the applications and principles of NIR-CDs in imaging, drug delivery, and non-invasive therapeutics are introduced from a view of diagnosis and therapy. Finally, their prospects and challenges in biomedical and biotechnological applications are outlined.

6.
Angew Chem Int Ed Engl ; : e202410938, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39092496

RESUMO

The electrocatalytic C-N coupling from CO2 and nitrate emerges as one of the solutions for waste upgrading and urea synthesis. In this work, we constructed electron-deficient Cu sites by the strong metal-polymer semiconductor interaction, to boost efficient and durable urea synthesis. In situ Raman spectroscopy identified the existence of electron-deficient Cu sites and was able to withstand electrochemical reduction conditions. Operando synchrotron-radiation Fourier transform infrared spectroscopy and theoretical calculations disclosed the vital role of electron-deficient Cu in adsorption and C-N coupling of oxygen-containing species. The electron-deficient Cu displayed a high urea yield rate of 255.0 mmol h-1 g-1 at -1.4 V versus the reversible hydrogen electrode and excellent electrochemical durability, superior than that of non-electron-deficient counterpart with conductive carbon material as the support. It can be concluded that the regulation of site electronic structure is more important than the optimization of catalyst conductive properties in the C-N coupling reactions.

7.
Curr Top Med Chem ; 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39092647

RESUMO

BACKGROUND: The synthesis of nanoparticles using the principle of green chemistry has achieved huge potential in nanomedicine. Here, we report the synthesis of silver nanoparticles (Ag- NPs) employing garlic essential oil (GEO) due to wide applications of GEO in the biomedical and pharmaceutical industry. OBJECTIVE: This study aimed to synthesise garlic essential oil-assisted silver nanoparticles and present their antimicrobial and antibiofilm activities with mechanistic assessment. METHOD: Initially, the formulation of AgNPs was confirmed using different optical techniques, such as XRD, FT-IR, DLS, zeta potential, SEM, and EDX analysis, which confirmed the formulation of well-dispersed, stable, and spherical AgNPs. The antimicrobial and antibiofilm activity of GEO-assisted AgNPs was evaluated against a spectrum of pathogenic microorganisms, such as Gram-positive (S. aureus and B. subtilis) and Gram-negative (E. coli and P. aeruginosa) bacteria. RESULTS: The AgNPs exhibited remarkable antimicrobial and anti-biofilm activity against all tested strains. The mechanism behind the antimicrobial activity of AgNPs was explored by estimating the amount of reactive oxygen species (ROS) generated due to the interaction of AgNP with bacterial cells and observing the morphological changes of bacteria upon AgNP interaction. CONCLUSION: The findings of this study concluded that ROS generation due to the interaction of AgNPs with bacterial cells put stress on bacterial membranes, altering the morphology of bacteria, exhibiting remarkable antimicrobial activity, and preventing biofilm formation.

8.
Small ; : e2404548, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39092680

RESUMO

Herein, a variety of 2,6-diaminopyridine (DAP) derived nitrogen-doped hierarchically porous carbon (DAP-NHPC-T) prepared from carbonization-induced structure transformation of DAP-Zn-SiO2-P123 nanocomposites are reported, which are facilely prepared from solvent-free co-assembly of block copolymer templates P123 with pyridine-rich monomer of DAP, Zn(NO3)2 and tetramethoxysilane. In the pyrolysis process, P123 and SiO2 templates promote the formation of mesoporous and supermicroporous structures in the DAP-NHPC-T, while high-temperature volatilization of Zn contributed to generation of micropores. The DAP-NHPC-T possess large BET surface areas (≈956-1126 m2 g-1), hierarchical porosity with micro-supermicro-mesoporous feature and high nitrogen contents (≈10.44-5.99 at%) with tunable density of pyridine-based nitrogen sites (≈5.99-3.32 at%), exhibiting good accessibility and reinforced interaction with SO2. Consequently, the DAP-NHPC-T show high SO2 capacity (14.7 mmol g-1, 25 °C and 1.0 bar) and SO2/CO2/N2 IAST selectivities, extraordinary dynamic breakthrough separation efficiency and cycling stability, far beyond any other reported nitrogen-doped metal-free carbon. As verified by in situ spectroscopy and theoretical calculations, the pyridine-based nitrogen sites of the DAP-NHPC-T boost SO2 adsorption via the unique charge transfer, the adsorption mechanism and reaction model have been finally clarified.

9.
Med Phys ; 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39088750

RESUMO

BACKGROUND: Although cone beam computed tomography (CBCT) has lower resolution compared to planning CTs (pCT), its lower dose, higher high-contrast resolution, and shorter scanning time support its widespread use in clinical applications, especially in ensuring accurate patient positioning during the image-guided radiation therapy (IGRT) process. PURPOSE: While CBCT is critical to IGRT, CBCT image quality can be compromised by severe stripe and scattering artifacts. Tumor movement secondary to respiratory motion also decreases CBCT resolution. In order to improve the image quality of CBCT, we propose a Lung Diffusion Model (L-DM) framework. METHODS: Our proposed algorithm is based on a conditional diffusion model trained on pCT and deformed CBCT (dCBCT) image pairs to synthesize lung CT images from dCBCT images and benefit CBCT-based radiotherapy. dCBCT images were used as the constraint for the L-DM. The image quality and Hounsfield unit (HU) values of the synthetic CTs (sCT) images generated by the proposed L-DM were compared to three selected mainstream generation models. RESULTS: We verified our model in both an institutional lung cancer dataset and a selected public dataset. Our L-DM showed significant improvement in the four metrics of mean absolute error (MAE), peak signal-to-noise ratio (PSNR), normalized cross-correlation (NCC), and structural similarity index measure (SSIM). In our institutional dataset, our proposed L-DM decreased the MAE from 101.47 to 37.87 HU and increased the PSNR from 24.97 to 29.89 dB, the NCC from 0.81 to 0.97, and the SSIM from 0.80 to 0.93. In the public dataset, our proposed L-DM decreased the MAE from 173.65 to 58.95 HU, while increasing the PSNR, NCC, and SSIM from 13.07 to 24.05 dB, 0.68 to 0.94, and 0.41 to 0.88, respectively. CONCLUSIONS: The proposed L-DM significantly improved sCT image quality compared to the pre-correction CBCT and three mainstream generative models. Our model can benefit CBCT-based IGRT and other potential clinical applications as it increases the HU accuracy and decreases the artifacts from input CBCT images.

10.
ACS Infect Dis ; 2024 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-39096289

RESUMO

SARS-CoV-2 and HCoV-OC43 belong to the same ß genus of the Coronaviridae family. SARS-CoV-2 was responsible for the recent COVID-19 pandemic, and HCoV-OC43 is the etiological agent of mild upper respiratory tract infections. SARS-COV-2 and HCoV-OC43 co-infections were found in children with respiratory symptoms during the COVID-19 pandemic. The two ß-coronaviruses share a high degree of homology between the 3CLpro active sites, so much so that the safer HCoV-OC43 has been suggested as a tool for the identification of new anti-SARS-COV-2 agents. Compounds 5 and 24 inhibited effectively both Wuhan and British SARS-CoV-2 patient isolates in Vero E6 cells and the HCoV-OC43 in MRC-5 cells at low micromolar concentrations. The inhibition was apparently exerted via targeting the 3CLpro active sites of both viruses. Compounds 5 and 24 at 100 µM inhibited the SARS-CoV-2 3CLpro activity of 61.78 and 67.30%, respectively. These findings highlight 5 and 24 as lead compounds of a novel class of antiviral agents with the potential to treat SARS-COV-2 and HCoV-OC43 infections.

11.
Sci Rep ; 14(1): 17942, 2024 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-39095513

RESUMO

Glycogen storage, conversion and utilization in astrocytes play an important role in brain energy metabolism. The conversion of glycogen to lactate through glycolysis occurs through the coordinated activities of various enzymes and inhibition of this process can impair different brain processes including formation of long-lasting memories. To replenish depleted glycogen stores, astrocytes undergo glycogen synthesis, a cellular process that has been shown to require transcription and translation during specific stimulation paradigms. However, the detail nuclear signaling mechanisms and transcriptional regulation during glycogen synthesis in astrocytes remains to be explored. In this report, we study the molecular mechanisms of vasoactive intestinal peptide (VIP)-induced glycogen synthesis in astrocytes. VIP is a potent neuropeptide that triggers glycogenolysis followed by glycogen synthesis in astrocytes. We show evidence that VIP-induced glycogen synthesis requires CREB-mediated transcription that is calcium dependent and requires conventional Protein Kinase C but not Protein Kinase A. In parallel to CREB activation, we demonstrate that VIP also triggers nuclear accumulation of the CREB coactivator CRTC2 in astrocytic nuclei. Transcriptome profiles of VIP-induced astrocytes identified robust CREB transcription, including a subset of genes linked to glucose and glycogen metabolism. Finally, we demonstrate that VIP-induced glycogen synthesis shares similar as well as distinct molecular signatures with glucose-induced glycogen synthesis, including the requirement of CREB-mediated transcription. Overall, our data demonstrates the importance of CREB-mediated transcription in astrocytes during stimulus-driven glycogenesis.


Assuntos
Astrócitos , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico , Glicogênio , Peptídeo Intestinal Vasoativo , Astrócitos/metabolismo , Glicogênio/metabolismo , Glicogênio/biossíntese , Animais , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Peptídeo Intestinal Vasoativo/metabolismo , Transcrição Gênica , Células Cultivadas , Proteína Quinase C/metabolismo , Regulação da Expressão Gênica , Camundongos , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Núcleo Celular/metabolismo
12.
Microb Cell Fact ; 23(1): 219, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39103877

RESUMO

BACKGROUND: Xanthenes and multi-aryl carbon core containing compounds represent different types of complex and condensed architectures that have impressive wide range of pharmacological, industrial and synthetic applications. Moreover, indoles as building blocks were only found in naturally occurring metabolites with di-aryl carbon cores and in chemically synthesized tri-aryl carbon core containing compounds. Up to date, rare xanthenes with indole bearing multicaryl carbon core have been reported in natural or synthetic products. The underlying mechanism of fluorescein-like arthrocolins with tetra-arylmethyl core were synthesized in an engineered Escherichia coli fed with toluquinol remained unclear. RESULTS: In this study, the Keio collection of single gene knockout strains of 3901 mutants of E. coli BW25113, together with 14 distinct E. coli strains, was applied to explore the origins of endogenous building blocks and the biogenesis for arthrocolin assemblage. Deficiency in bacterial respiratory and aromatic compound degradation genes ubiX, cydB, sucA and ssuE inhibited the mutant growth fed with toluquinol. Metabolomics of the cultures of 3897 mutants revealed that only disruption of tnaA involving in transforming tryptophan to indole, resulted in absence of arthrocolins. Further media optimization, thermal cell killing and cell free analysis indicated that a non-enzyme reaction was involved in the arthrocolin biosynthesis in E. coli. Evaluation of redox potentials and free radicals suggested that an oxygen-mediated free radical reaction was responsible for arthrocolins formation in E. coli. Regulation of oxygen combined with distinct phenol derivatives as inducer, 31 arylmethyl core containing metabolites including 13 new and 8 biological active, were isolated and characterized. Among them, novel arthrocolins with p-hydroxylbenzene ring from tyrosine were achieved through large scale of aerobic fermentation and elucidated x-ray diffraction analysis. Moreover, most of the known compounds in this study were for the first time synthesized in a microbe instead of chemical synthesis. Through feeding the rat with toluquinol after colonizing the intestines of rat with E. coli, arthrocolins also appeared in the rat blood. CONCLUSION: Our findings provide a mechanistic insight into in vivo synthesis of complex and condensed arthrocolins induced by simple phenols and exploits a quinol based method to generate endogenous aromatic building blocks, as well as a methylidene unit, for the bacteria-facilitated synthesis of multiarylmethanes.


Assuntos
Escherichia coli , Oxigênio , Fenóis , Escherichia coli/metabolismo , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Fenóis/metabolismo , Oxigênio/metabolismo , Radicais Livres/metabolismo , Metano/metabolismo , Animais , Ratos , Indóis/metabolismo
13.
Iran J Pharm Res ; 23(1): e144928, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39108649

RESUMO

Background: Lately, there has been increasing interest in the benefits of metal-organic frameworks, and among them, zeolitic imidazolate frameworks (ZIF - 8) stand out as one of the most commonly employed systems owing to their unique characteristics. Objectives: Given that properties like particle size play a key role in biomedical applications of nanoparticles, optimizing the synthesis conditions becomes crucial. Additionally, it is essential to label these nanoparticles to track them effectively within the body. Methods: Zeolitic imidazolate frameworks nanoparticles were synthesized under various conditions, including high and room temperature, using two different solvents: Water and methanol. Modifications were made to the reaction temperature and the ratio of reactants to improve the outcomes. Particle size and size distribution were assessed in all conditions. Additionally, the radiolabeling of nanoparticles was examined using four different methods to identify the method with the highest efficiency and radiochemical purity. Results: The optimum conditions for ZIF-8 synthesis were determined at 50°C using methanol as the solvent. A reactant weight ratio of 1: 2 (zinc nitrate to 2-methylimidazole) was utilized. The most effective radiolabeling approach involved using tin chloride as a reducing agent, with the reaction mixture maintained at a temperature of 70°C for 30 minutes. Conclusions: In this study, the optimum conditions were successfully identified for synthesizing and labeling ZIF-8 nanoparticles. These nanoparticles have the potential to serve as effective carriers for diagnostic and therapeutic agents.

14.
Front Reprod Health ; 6: 1394978, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39109074

RESUMO

Introduction: Dysmenorrhoea affects many adolescents with significant impacts on education and well-being. In the UK, most of the adolescents who seek care (and many never do), will do so through general practice (primary care). Knowing how best to care for adolescents reporting menstrual pain is an area where UK general practitioners would like better guidance and resources. Methods: This mixed-methods narrative synthesis collates community and specialist evidence from 320 papers about adolescent dysmenorrhoea, with a UK general practice community health perspective. Results: We report a narrative summary of symptoms, cause, consequences and treatments for adolescent dysmenorrhoea. We highlight areas of tension or conflicted evidence relevant to primary care alongside areas of uncertainty and research gaps identified through this synthesis with input from lived experience advisers. Discussion: There is little evidence about primary care management of adolescent dysmenorrhoea or specific resources to support shared-decision making in general practice, although there are evidence-based treatments to offer. Primary care encounters also represent potential opportunities to consider whether the possibility of underlying or associated health conditions contributing to symptoms of dysmenorrhoea, but there is little epidemiological evidence about prevalence from within community health settings to inform this. The areas where there is little or uncertain evidence along the care journey for adolescent dysmenorrhoea, including at the interface between experience and expression of symptoms and potential underlying contributory causes warrant further exploration. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPEROFILES/256458_STRATEGY_20210608.pdf, identifier (CRD42021256458).

15.
Angew Chem Int Ed Engl ; : e202411861, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39110601

RESUMO

Starphenes are structurally appealing three-fold symmetric polycyclic aromatic compounds with potential interesting applications in molecular electronics and nanotechnology. This family of star-shaped polyarenes can be regarded as three acenes that are connected through a single benzene ring. In fact, just like acenes, unsubstituted large starphenes are poorly soluble and highly reactive molecules under ambient conditions making their synthesis difficult to achieve. Herein, we report two different synthetic strategies to obtain a starphene formed by 19 cata-fused benzene rings distributed within three hexacene branches. This molecule, which is the largest starphene that has been obtained to date, was prepared by combining solution-phase and on-surface synthesis. [19]Starphene was characterized by high-resolution scanning tunneling microscopy (STM) and spectroscopy (STS) showing a remarkable small HOMO-LUMO transport gap (0.9 eV).

16.
Nucleic Acid Ther ; 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39110607

RESUMO

Oligonucleotide therapeutics, a pioneering category of modern medicinal drugs, are at the forefront of utilizing innate mechanisms to modulate gene expression. With 18 oligonucleotide-based FDA-approved medicines currently available for treating various clinical conditions, this field showcases an innovative potential yet to be fully explored. Factors such as purity, formulation, and endotoxin levels profoundly influence the efficacy and safety of these therapeutics. Therefore, a thorough understanding of the chemical factors essential for producing high-quality oligonucleotides for preclinical studies is crucial in their development for further clinical application. This paper serves as a concise guide to these chemical considerations, aiming to inspire and equip researchers with the necessary knowledge to advance in this exciting and innovative field.

17.
Food Chem ; 460(Pt 3): 140727, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39111045

RESUMO

The present study involved the synthesis and analysis of a lipophilic form of vitamin C, namely tetrabutyryl vitamin C ester (TVCE). TVCE is synthesized by a simple one-step method, combining the advantages of VC and butyric acid. Its antioxidant efficacy on sunflower seed oil frying was evaluated by assessing lipid oxidation parameters including peroxide number (POV), carbonyl number (CV), and paraniline number (pAV). Furthermore, changes in the fatty acid composition of the oil were monitored using techniques such as infrared spectroscopy (IR), nuclear magnetic resonance (NMR), and gas chromatography (GC). The findings demonstrated that lipophilic vitamin C exhibited superior protection against oxidation during frying compared to vitamin E, suggesting that it may be an effective fat-soluble antioxidant. The study provides a new field for the utilization of vitamin C and a new idea for the development of efficient antioxidants.

18.
NMR Biomed ; : e5221, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39113170

RESUMO

Chemical exchange saturation transfer (CEST) MRI at 3 T suffers from low specificity due to overlapping CEST effects from multiple metabolites, while higher field strengths (B0) allow for better separation of Z-spectral "peaks," aiding signal interpretation and quantification. However, data acquisition at higher B0 is restricted by equipment access, field inhomogeneity and safety issues. Herein, we aim to synthesize higher-B0 Z-spectra from readily available data acquired with 3 T clinical scanners using a deep learning framework. Trained with simulation data using models based on Bloch-McConnell equations, this framework comprised two deep neural networks (DNNs) and a singular value decomposition (SVD) module. The first DNN identified B0 shifts in Z-spectra and aligned them to correct frequencies. After B0 correction, the lower-B0 Z-spectra were streamlined to the second DNN, casting into the key feature representations of higher-B0 Z-spectra, obtained through SVD truncation. Finally, the complete higher-B0 Z-spectra were recovered from inverse SVD, given the low-rank property of Z-spectra. This study constructed and validated two models, a phosphocreatine (PCr) model and a pseudo-in-vivo one. Each experimental dataset, including PCr phantoms, egg white phantoms, and in vivo rat brains, was sequentially acquired on a 3 T human and a 9.4 T animal scanner. Results demonstrated that the synthetic 9.4 T Z-spectra were almost identical to the experimental ground truth, showing low RMSE (0.11% ± 0.0013% for seven PCr tubes, 1.8% ± 0.2% for three egg white tubes, and 0.79% ± 0.54% for three rat slices) and high R2 (>0.99). The synthesized amide and NOE contrast maps, calculated using the Lorentzian difference, were also well matched with the experiments. Additionally, the synthesis model exhibited robustness to B0 inhomogeneities, noise, and other acquisition imperfections. In conclusion, the proposed framework enables synthesis of higher-B0 Z-spectra from lower-B0 ones, which may facilitate CEST MRI quantification and applications.

19.
BMC Palliat Care ; 23(1): 200, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39098890

RESUMO

BACKGROUND: Patients living with life-limiting illnesses other than cancer constitute the majority of patients in need of palliative care globally, yet most previous systematic reviews of the cost impact of palliative care have not exclusively focused on this population. Reviews that tangentially looked at non-cancer patients found inconclusive evidence. Randomised controlled trials (RCTs) are the gold standard for treatment efficacy, while total health care costs offer a comprehensive measure of resource use. In the sole review of RCTs for non-cancer patients, palliative care reduced hospitalisations and emergency department visits but its effect on total health care costs was not assessed. The aim of this study is to review RCTs to determine the difference in costs between a palliative care approach and usual care in adult non-cancer patients with a life-limiting illness. METHODS: A systematic review using a narrative synthesis approach. The protocol was registered with PROSPERO prospectively (no. CRD42020191082). Eight databases were searched: Medline, CINAHL, EconLit, EMBASE, TRIP database, NHS Evidence, Cochrane Library, and Web of Science from inception to January 2023. Inclusion criteria were: English or German; randomised controlled trials (RCTs); adult non-cancer patients (> 18 years); palliative care provision; a comparator group of standard or usual care. Quality of studies was assessed using Drummond's checklist for assessing economic evaluations. RESULTS: Seven RCTs were included and examined the following diseases: neurological (3), heart failure (2), AIDS (1) and mixed (1). The majority (6/7) were home-based interventions. All studies were either cost-saving (3/7) or cost-neutral (4/7); and four had improved outcomes for patients or carers and three no change in outcomes. CONCLUSIONS: In a non-cancer population, this is the first systematic review of RCTs that has demonstrated a palliative care approach is cost-saving or at least cost-neutral. Cost savings are achieved without worsening outcomes for patients and carers. These findings lend support to calls to increase palliative care provision globally.


Assuntos
Cuidados Paliativos , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Cuidados Paliativos/economia , Cuidados Paliativos/métodos , Cuidados Paliativos/normas , Adulto , Redução de Custos/métodos , Redução de Custos/estatística & dados numéricos , Análise Custo-Benefício/métodos
20.
Health Expect ; 27(1): e13974, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-39102698

RESUMO

BACKGROUND: An often-hidden element in healthcare students' education is the pedagogy of public involvement, yet public participation can result in deep learning for students with positive impacts on the public who participate. OBJECTIVE: This article aimed to synthesize published literature reviews that described the impact of public participation in healthcare students' education. SEARCH STRATEGY: We searched MEDLINE, EMBASE, ERIC, PsychINFO, CINAHL, PubMed, JBI Database of Systematic Reviews and Implementation Reports, the Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects and the PROSPERO register for literature reviews on public participation in healthcare students' education. INCLUSION CRITERIA: Reviews published in the last 10 years were included if they described patient or public participation in healthcare students' education and reported the impacts on students, the public, curricula or healthcare systems. DATA EXTRACTION AND SYNTHESIS: Data were extracted using a predesigned data extraction form and narratively synthesized. MAIN RESULTS: Twenty reviews met our inclusion criteria reporting on outcomes related to students, the public, curriculum and future professional practice. DISCUSSION AND CONCLUSION: Our findings raise awareness of the benefits and challenges of public participation in healthcare students' education and may inform future research exploring how public participation can best be utilized in higher education. PATIENT OR PUBLIC CONTRIBUTION: This review was inspired by conversations with public healthcare consumers who saw value in public participation in healthcare students' education. Studies included involved public participants, providing a deeper understanding of the impacts of public participation in healthcare students' education.


Assuntos
Participação da Comunidade , Humanos , Currículo , Estudantes de Ciências da Saúde
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