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1.
Sci Rep ; 14(1): 7168, 2024 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-38532056

RESUMO

Chemical pesticide delivery is a fundamental aspect of agriculture. However, the extensive use of pesticides severely endangers the ecosystem because they accumulate on crops, in soil, as well as in drinking and groundwater. New frontiers in nano-engineering have opened the door for precision agriculture. We introduced Tobacco mild green mosaic virus (TMGMV) as a viable delivery platform with a high aspect ratio and favorable soil mobility. In this work, we assess the use of TMGMV as a chemical nanocarrier for agriculturally relevant cargo. While plant viruses are usually portrayed as rigid/solid structures, these are "dynamic materials," and they "breathe" in solution in response to careful adjustment of pH or bathing media [e.g., addition of solvent such as dimethyl sulfoxide (DMSO)]. Through this process, coat proteins (CPs) partially dissociate leading to swelling of the nucleoprotein complexes-allowing for the infusion of active ingredients (AI), such as pesticides [e.g., fluopyram (FLP), clothianidin (CTD), rifampicin (RIF), and ivermectin (IVM)] into the macromolecular structure. We developed a "breathing" method that facilitates inter-coat protein cargo loading, resulting in up to ~ 1000 AIs per virion. This is of significance since in the agricultural setting, there is a need to develop nanoparticle delivery strategies where the AI is not chemically altered, consequently avoiding the need for regulatory and registration processes of new compounds. This work highlights the potential of TMGMV as a pesticide nanocarrier in precision farming applications; the developed methods likely would be applicable to other protein-based nanoparticle systems.


Assuntos
Praguicidas , Vírus do Mosaico do Tabaco , Tobamovirus , Ecossistema , Praguicidas/metabolismo , Solo , Vírion
2.
ACS Nano ; 18(12): 8649-8662, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38471029

RESUMO

There has been much interest in integrating various inorganic nanoparticles (nanoscale colloids) in biology and medicine. However, buildup of a protein corona around the nanoparticles in biological media, driven by nonspecific interactions, remains a major hurdle for the translation of nanomedicine into clinical applications. In this study, we investigate the interactions between gold nanoparticles and serum proteins using a series of dihydrolipoic acid (DHLA)-based ligands. We employed gel electrophoresis combined with UV-vis absorption and dynamic light scattering to correlate protein adsorption with the nature and size of the ligand used. For instance, we found that AuNPs capped with DHLA alone promote nonspecific protein adsorption. In comparison, capping AuNPs with polyethylene glycol- or zwitterion-appended DHLA essentially prevents corona formation, regardless of ligand charge and size. Our results highlight the crucial role of surface chemistry and core material in protein corona formation and offer valuable information for the design of colloidal nanomaterials for biological applications.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Coroa de Proteína , Ouro , Ligantes , Proteínas
3.
United European Gastroenterol J ; 12(2): 226-239, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38372444

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common cancers and a leading cause of cancer-related mortality. Locoregional therapies (LRTs) play a crucial role in HCC management and are selectively adopted in real-world practice across various stages. Choosing the best form of LRTs depends on technical aspects, patient clinical status and tumour characteristics. Previous studies have consistently highlighted the efficacy of combining LRTs with molecular targeted agents in HCC treatment. Recent studies propose that integrating LRTs with immune checkpoint inhibitors and molecular targeted agents could provide substantial therapeutic benefits, a notion underpinned by both basic and clinical evidence. This review summarised the current landscape of LRTs in HCC and discussed the anticipated outcomes of combinations with immunotherapy regimens.


Assuntos
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Resultado do Tratamento , Imunoterapia , Antineoplásicos/uso terapêutico
4.
Adv Mater ; : e2307679, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38372431

RESUMO

Triggering lysosome-regulated immunogenic cell death (ICD, e.g., pyroptosis and necroptosis) with nanomedicines is an emerging approach for turning an "immune-cold" tumor "hot"-a key challenge faced by cancer immunotherapies. Proton sponge such as high-molecular-weight branched polyethylenimine (PEI) is excellent at rupturing lysosomes, but its therapeutic application is hindered by uncontrollable toxicity due to fixed charge density and poor understanding of resulted cell death mechanism. Here, a series of proton sponge nano-assemblies (PSNAs) with self-assembly controllable surface charge density and cell cytotoxicity are created. Such PSNAs are constructed via low-molecular-weight branched PEI covalently bound to self-assembling peptides carrying tetraphenylethene pyridinium (PyTPE, an aggregation-induced emission-based luminogen). Assembly of PEI assisted by the self-assembling peptide-PyTPE leads to enhanced surface positive charges and cell cytotoxicity of PSNA. The self-assembly tendency of PSNAs is further optimized by tuning hydrophilic and hydrophobic components within the peptide, thus resulting in the PSNA with the highest fluorescence, positive surface charge density, cell uptake, and cancer cell cytotoxicity. Systematic cell death mechanistic studies reveal that the lysosome rupturing-regulated pyroptosis and necroptosis are at least two causes of cell death. Tumor cells undergoing PSNA-triggered ICD activate immune cells, suggesting the great potential of PSNAs to trigger anticancer immunity.

5.
BMC Cancer ; 24(1): 257, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38395838

RESUMO

BACKGROUND: CCRT is presently the standard treatment for LA-NSCLC. RP is one of the main obstacles to the completion of thoracic radiation therapy, resulting in limited survival benefits in NSCLC patients. This research aims to explore the role of Endostar in the occurrence of grade≥2 RP and clinical curative effect in LA-NSCLC patients. METHODS: This study retrospectively analyzed 122 patients with stage III NSCLC who received CCRT from December 2008 to December 2017, or Endostar intravenous drip concurrently with chemoradiotherapy (Endostar + CCRT group). Standard toxicity of the pneumonitis endpoint was also collected by CTCAE V5.0. We further summarized other available studies on the role of Endostar in the prognosis of NSCLC patients and the incidence of RP. RESULTS: There were 76 cases in the CCRT group and 46 cases in the CCRT+ Endostar group. In the CCRT+ Endostar group, the occurrence of grade ≥2 RP in patients with V20Gy ≥25% was significantly higher than that in patients with V20Gy < 25% (p = 0.001). In the cohorts with V20Gy < 25%, 0 cases of 29 patients treated with Endostar developed grade ≥2 RP was lower than in the CCRT group (p = 0.026). The re-analysis of data from other available studies indicated that Endostar plus CCRT could be more efficient and safely in the occurrence of grade≥2 RP with LA-NSCLC. CONCLUSIONS: When receiving CCRT for LA-NSCLC patients, simultaneous combination of Endostar is recommended to enhance clinical benefit and reduce pulmonary toxicity.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Endostatinas , Neoplasias Pulmonares , Pneumonia , Pneumonite por Radiação , Proteínas Recombinantes , Humanos , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/tratamento farmacológico , Estudos Retrospectivos , Quimiorradioterapia/efeitos adversos , Quimiorradioterapia/métodos , Pneumonia/induzido quimicamente , Pneumonia/epidemiologia , Pneumonite por Radiação/epidemiologia , Pneumonite por Radiação/etiologia
6.
Neoplasia ; 48: 100969, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38199173

RESUMO

PURPOSE: To look into the relationship between cardiac substructures (CS) dosimetric parameters and cardiac events (CE) or overall survival (OS) in patients undergoing radiation therapy (RT) for esophageal squamous cell carcinoma (ESCC). METHODS AND MATERIALS: A retrospective study included 350 patients with ESCC receiving definitive chemoradiotherapy or radiotherapy (d-CRT/d-RT) or neoadjuvant chemoradiotherapy (NCRT) from March 2013 to May 2022. Our study examined the adverse cardiac events of any grade or G3+, as defined by the Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. Competing risk analysis and Cox regression analysis were used to assess the relationship between CS doses and CEs or OS. RESULTS: 201 (57.4 %) patients received any grade CEs over a median follow-up time of 22.50 months (IQR, 12.40-45.60), and 24 (6.86 %) patients suffered G3+ CEs. On landmark analysis, patients with any grade CEs had significantly lower OS (P = 0.003). Multivariable analysis revealed that any grade CEs were predicted by the dose of CSs in all populations. In addition, for G3+ cardiac events, arrhythmic and small probability of cardiac events, LAD V20 ((HR: 1.02, 95 % CI: 1.00-1.03, P = 0.012; HR: 1.01, 95 % CI: 1.00-1.02, P = 0.005; HR; 1.01, 95 % CI: 1.00-1.02, P = 0.012) was also an independent predictive factor. LAD V50 (HR: 1.07, 95 % CI: 1.03-1.10, P <0.001) predicted pericardium effusion events. Moreover, the multivariable analysis revealed that OS was predicted by LAD V30 (HR: 1.03; 95 % CI, 1.01-1.05, P = 0.015). CONCLUSIONS: In the population of ESCC patients receiving RT, we showed that the CS factors had a substantial predictive value for the various types and grades of CEs. The elevated radiation dose of LAD was a significant contributor to a higher rate of cardiac events and a worse prognosis.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas do Esôfago/diagnóstico , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/tratamento farmacológico , Cardiotoxicidade/diagnóstico , Cardiotoxicidade/etiologia , Cardiotoxicidade/tratamento farmacológico , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/radioterapia , Neoplasias Esofágicas/tratamento farmacológico , Estudos Retrospectivos , Prognóstico , Quimiorradioterapia/efeitos adversos , Células Epiteliais/patologia
7.
J Clin Transl Hepatol ; 12(1): 15-24, 2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38250466

RESUMO

Background and Aims: Several first-line immune checkpoint inhibitor (ICI)-based combination therapies have been identified for unresectable hepatocellular carcinoma (uHCC). This network meta-analysis (NMA) aimed to provide the most updated evidence about the preferred first-line ICI-based regimens for uHCC. Methods: A comprehensive literature search was performed in various databases from database inception to May 2022. The phase 3 trials evaluating first-line single-agent ICIs, molecular-target agents (MTAs), or their combinations in uHCC were included. The main endpoints were overall survival (OS) and progression-free survival (PFS). Pooled effect estimates were calculated using a random effects model within the frequentist framework. Subgroup analyses based on etiology were also conducted. Results: Twelve trials at low risk of bias with 8,275 patients comparing 13 treatments were included. OS with atezolizumab plus bevacizumab was comparable to sintilimab plus IBI305 [hazard ratio (HR): 1.16; 95% confidence interval (CI): 0.80-1.68] and camrelizumab plus apatinib (HR: 1.06; 95% CI: 0.75-1.51). The combination therapies, apart from atezolizumab plus cabozantinib in OS and durvalumab plus tremelimumab in PFS, had higher P-score than single-agent MTAs or ICIs. The survival benefits were associated with a high risk of adverse events leading to treatment discontinuation. The proportion of patients with hepatitis B virus-related HCC receiving ICIs combinations might positively correlate with survival advantages (R2=0.8039, p=0.0155). Conclusion: This NMA demonstrated that atezolizumab plus bevacizumab remains the stand of care and confers comparable survival benefits to sintilimab plus IBI305 and camrelizumab plus apatinib in first-line therapy for uHCC. The optimal treatment algorithms should consider efficacy, safety, and etiology.

8.
Adv Sci (Weinh) ; 11(5): e2302816, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38058273

RESUMO

Vitrimers are an innovative class of polymers that boast a remarkable fusion of mechanical and dynamic features, complemented by the added benefit of end-of-life recyclability. This extraordinary blend of properties makes them highly attractive for a variety of applications, such as the automotive sector, soft robotics, and the aerospace industry. At their core, vitrimer materials consist of crosslinked covalent networks that have the ability to dynamically reorganize in response to external factors, including temperature changes, pressure variations, or shifts in pH levels. In this review, the aim is to delve into the latest advancements in the theoretical understanding and computational design of vitrimers. The review begins by offering an overview of the fundamental principles that underlie the behavior of these materials, encompassing their structures, dynamic behavior, and reaction mechanisms. Subsequently, recent progress in the computational design of vitrimers is explored, with a focus on the employment of molecular dynamics (MD)/Monte Carlo (MC) simulations and density functional theory (DFT) calculations. Last, the existing challenges and prospective directions for this field are critically analyzed, emphasizing the necessity for additional theoretical and computational advancements, coupled with experimental validation.

9.
Dalton Trans ; 53(2): 467-483, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38078852

RESUMO

There has been much interest in evaluating the strength of the coordination interactions between N-heterocyclic carbene (NHC) molecules and transition metal ions, nanocolloids and surfaces. We implement a top-down core digestion test of Au nanoparticles (AuNPs) triggered by incubation with a large molar excess of poly(ethylene glycol)-appended NHC molecules, where kinetic dislodging of surface atoms and formation of NHC-Au complexes progressively take place. We characterize the structure and chemical nature of the generated PEG-NHC-Au complexes using 1D and 2D 1H-13C NMR spectroscopy, supplemented with matrix assisted laser desorption/ionization mass spectrometry, and transmission electron microscopy. We further apply the same test using thiol-modified molecules and find that though etching can be measured the kinetics are substantially slower. We discuss our findings within the classic digestion of transition metal ores and colloids induced by interactions with sodium cyanide, which provides an insight into the strength of coordination between the strong σ-donating (soft Lewis base) NHC and Au surfaces (having a soft Lewis acid character), as compared to gold-to-gold covalent binding.

10.
J Am Chem Soc ; 145(47): 25664-25672, 2023 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-37921495

RESUMO

Polymeric spherulites are typically formed by melt crystallization: spherulitic growth in solution is rare and requires complex polymers and dilute solutions. Here, we report the mild and unique formation of luminescent spherulites at room temperature via the simple molecule benzene-1,4-dithiol (BDT). Specifically, BDT polymerized into oligomers (PBDT) via disulfide bonds and assembled into uniform supramolecular nanoparticles in aqueous buffer; these nanoparticles were then dissolved back into PBDT in a good solvent (i.e., dimethylformamide) and underwent chain elongation to form spherulites (rPBDT) in 10 min. The spherulite geometry was modulated by changing the PBDT concentration and reaction time. Due to the step-growth polymerization and reorganization of PBDT, these spherulites not only exhibited robust structure but also showed broad clusterization-triggered emission. The biocompatibility and efficient cellular uptake of the spherulites further underscore their value as traceable drug carriers. This system provides a new pathway for designing versatile superstructures with value for hierarchical assembly of small molecules into a complicated biological system.


Assuntos
Nanopartículas , Polímeros , Cristalização , Polímeros/química , Congelamento
11.
Arthritis Res Ther ; 25(1): 213, 2023 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-37899440

RESUMO

BACKGROUND: Cardiovascular (CV) risk estimation calculators for the general population underperform in patients with rheumatoid arthritis (RA). The purpose of this study was to identify relevant protein biomarkers that could be added to traditional CV risk calculators to improve the capacity of coronary artery calcification (CAC) prediction in individuals with RA. In a second step, we quantify the improvement of this prediction of CAC when these circulating biomarkers are added to standard risk scores. METHODS: A panel of 141 serum and plasma proteins, which represent a broad base of both CV and RA biology, were evaluated and prioritized as candidate biomarkers. Of these, 39 proteins were selected and measured by commercial ELISA or quantitative mass spectroscopy in 561 individuals with RA in whom a measure of CAC and frozen sera were available. The patients were randomly split 50:50 into a training/validation cohort. Discrimination (using area under the receiver operator characteristic curves) and re-classification (through net reclassification improvement and integrated discrimination improvement calculation) analyses were performed first in the training cohort and replicated in the validation cohort, to estimate the increase in prediction accuracy for CAC using the ACA/AHA (American College of Cardiology and the American Heart Association) score with, compared to without, addition of these circulating biomarkers. RESULTS: The model containing ACC/AHA score plus cytokines (osteopontin, cartilage glycoprotein-39, cystatin C, and chemokine (C-C motif) ligand 18) and plus quantitative mass spectroscopy biomarkers (serpin D1, paraoxonase, and clusterin) had a statistically significant positive net reclassifications index and integrated discrimination improvement for the prediction of CAC, using ACC/AHA score without any biomarkers as the reference category. These results were confirmed in the validation cohort. CONCLUSION: In this exploratory analysis, the addition of several circulating CV and RA biomarkers to a standard CV risk calculator yielded significant improvements in discrimination and reclassification for the presence of CAC in individuals with RA.


Assuntos
Artrite Reumatoide , Aterosclerose , Doença da Artéria Coronariana , Humanos , Estados Unidos , Medição de Risco , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/epidemiologia , Artrite Reumatoide/complicações , Artrite Reumatoide/epidemiologia , Biomarcadores , Aterosclerose/complicações
12.
Chem Commun (Camb) ; 59(83): 12459-12462, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37782049

RESUMO

We report here a colorimetric method for rapid detection of norovirus based on the valence-driven peptide-AuNP interactions. We engineered a peptide sequence named K1 with a cleavage sequence in between two lysine residues. The positively charged lysine groups aggregated the negatively charged nanoparticles leading to a purple color change. There was a red color when the cleavage sequence was digested by the Southampton norovirus 3C-like protease (SV3CP)-a protease involved in the life cycle of Human norovirus (HNV). The limit of detection was determined to be 320 nM in Tris buffer. We further show that the sensor has good performance in exhaled breath condensate, urine, and faecal matter. This research provides a potential easy and quick way to selectively detect HNV.


Assuntos
Nanopartículas Metálicas , Norovirus , Humanos , Peptídeo Hidrolases , Colorimetria/métodos , Norovirus/química , Lisina , Peptídeos , Nanopartículas Metálicas/química , Ouro/química
14.
J Phys Chem B ; 127(37): 8009-8018, 2023 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-37683185

RESUMO

The surface of gold nanoparticles (AuNPs) can be conjugated with a wide range of highly functional biomolecules. A common pitfall when utilizing AuNPs is their tendency to aggregate, especially when their surface is functionalized with ligands of low molecular weight (no steric repulsion) or ligands of neutral charge (no electrostatic repulsion). For biomedical applications, AuNPs that are colloidally stable are desirable because they have a high surface area and thus reactivity, resist sedimentation, and exhibit uniform optical properties. Here, we engineer the surface of AuNPs so that they remain stable when decorated with coiled-coil (CC) peptides while preserving the native polypeptide properties. We achieve this by using a neutral, mixed ligand layer composed of lipoic acid poly(ethylene glycol) and lipoic acid poly(ethylene glycol) maleimide to attach the CCs. Tuning the surface fraction of each component within the mixed ligand layer also allowed us to control the degree of AuNP labeling with CCs. We demonstrate the dynamic surface properties of these CC-AuNPs by performing a place-exchange reaction and their utility by designing an energy-transfer-based caspase-3 sensor. Overall, this study optimizes the surface chemistry of AuNPs to quantitatively present functional biomolecules while maintaining colloid stability.


Assuntos
Nanopartículas Metálicas , Ácido Tióctico , Ouro , Ligantes , Peptídeos , Polietilenoglicóis
15.
J Clin Med ; 12(18)2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37762993

RESUMO

BACKGROUND: An accurate measurement of the glomerular filtration rate (GFR) is essential for detecting renal insufficiency in living kidney donors. Iohexol is a "near-ideal" exogenous filtration marker for GFR measurements that has attracted increasing interest in clinical practice because it is non-toxic, non-radioactive, readily available, and easy to measure. In this study, we aimed to set up a laboratory test to conveniently assess the plasma clearance of iohexol in living kidney donors. METHODS: A workflow was established in the institution's infusion clinic to administer iohexol and to collect three timed blood samples from renal transplant donors. Iohexol was thereafter measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The serum proteins were precipitated and the supernatant containing iohexol was diluted prior to the LC-MS/MS analysis. The LC-MS/MS method was developed on a Thermo Vanquish UHPLC coupled with a TSQ Endura triple quadruple mass spectrometer with a total run time of 2.5 min. The analytical performance of the method was assessed. RESULTS: The LC-MS/MS method demonstrated a good analytical performance. To calculate the iohexol clearance rate and the GFR, automated data integration and a result calculation were accomplished by using a custom Python script. Automated result reporting was achieved using a laboratory informatics system (LIS) vendor's direct media interface. CONCLUSIONS: We developed and implemented a laboratory test to assess the plasma clearance of iohexol. A workflow was established in the hospital to reliably measure the GFR in living kidney donors, with a potential to be further expanded into other areas where an accurate GFR measurement is needed.

16.
ACS Appl Mater Interfaces ; 15(36): 42293-42303, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37651748

RESUMO

Colorimetric biosensors based on gold nanoparticle (AuNP) aggregation are often challenged by matrix interference in biofluids, poor specificity, and limited utility with clinical samples. Here, we propose a peptide-driven nanoscale disassembly approach, where AuNP aggregates induced by electrostatic attractions are dissociated in response to proteolytic cleavage. Initially, citrate-coated AuNPs were assembled via a short cationic peptide (RRK) and characterized by experiments and simulations. The dissociation peptides were then used to reversibly dissociate the AuNP aggregates as a function of target protease detection, i.e., main protease (Mpro), a biomarker for severe acute respiratory syndrome coronavirus 2. The dissociation propensity depends on peptide length, hydrophilicity, charge, and ligand architecture. Finally, our dissociation strategy provides a rapid and distinct optical signal through Mpro cleavage with a detection limit of 12.3 nM in saliva. Our dissociation peptide effectively dissociates plasmonic assemblies in diverse matrices including 100% human saliva, urine, plasma, and seawater, as well as other types of plasmonic nanoparticles such as silver. Our peptide-enabled dissociation platform provides a simple, matrix-insensitive, and versatile method for protease sensing.


Assuntos
COVID-19 , Nanopartículas Metálicas , Humanos , Ouro , Peptídeos , Peptídeo Hidrolases
17.
Spectrochim Acta A Mol Biomol Spectrosc ; 303: 123275, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37611522

RESUMO

The global pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a great disaster to the economy and human society. Nowadays, SARS-CoV-2 is fading away from people's memory but it still exists around us. PCR plays an important role in detecting SARS-CoV-2 but it requires a long detecting time, equipped laboratory, and professional operators. In comparison with polymerase chain reaction (PCR), surface-enhanced Raman scattering (SERS) is a promising method for detecting SARS-CoV-2 due to its fast, easily operated, and high-sensitivity properties. In this study, the monolayer Ag nanoparticles (MAgNPs) covered with single-layer graphene (SLG) are applied as a SERS substrate. The angiotensin converting enzyme 2 (ACE2) is selected as a bio-probes that can specifically bind to the SARS-CoV-2 S protein. The SERS-based biosensor is formed by ACE2 functionalized SLG/MAgNPs and the LODs of detecting SARS-CoV-2 S protein in phosphate-buffered saline (PBS) and in pharyngeal swabs solution (PSS) are 0.1 fg mL-1 and 10 fg mL-1, respectively. This biosensor provides a way of directly detecting SARS-CoV-2 S protein with high sensitivity and specificity. It illustrates a practical potential in the rapid detection of the SARS-CoV-2 virus.


Assuntos
COVID-19 , Grafite , Nanopartículas Metálicas , Humanos , Enzima de Conversão de Angiotensina 2 , COVID-19/diagnóstico , SARS-CoV-2 , Prata , Glicoproteína da Espícula de Coronavírus
18.
Dentomaxillofac Radiol ; 52(8): 20230066, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37641889

RESUMO

OBJECTIVE: To develop a novel technique for localizing and reconstructing the greater palatine artery (GPA) using three-dimensional (3D) technology. METHODS: A miniaturized intraoral ultrasound transducer was used to imaging landmarks including the GPA, gingival margin (GM), and palatal masticatory mucosa (PMM). A 5-mm-thick solid hydrogel couplant was integrated to replace traditional ultrasound gel and avoid bubbles when moving the transducer. RESULTS: A panorama image provided the relative localization of landmarks including the GPA, PMM, and hard palate. Short- and long-axis imaging of GPA was performed in five subjects including 3D mapping of GPA branches and surrounding tissues in a volume of 10 mm × 8 mm × 10 mm. Full-mouth Doppler imaging was also demonstrated on both the dorsal and ventral tongue as well as buccal mucosa and sublingual region on two subjects. CONCLUSIONS: This study can measure the vertical distance from the GM to the GPA and depth from PMM to GPA and visualize the GPA localization in a 3D manner, which is critical to evaluate the available volume of palatal donor tissues and avoid sectioning of GPA during surgical harvesting of the tissues. Finally, the transducer's small size facilitates full-mouth Doppler imaging with the potential to improve the assessment, diagnosis, and management of oral mucosa.


Assuntos
Artérias , Palato Duro , Humanos , Artérias/diagnóstico por imagem , Mucosa Bucal , Face
19.
Analyst ; 148(18): 4504-4512, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37578304

RESUMO

Noroviruses are highly contagious and are one of the leading causes of acute gastroenteritis worldwide. Due to a lack of effective antiviral therapies, there is a need to diagnose and surveil norovirus infections to implement quarantine protocols and prevent large outbreaks. Currently, the gold standard of diagnosis uses reverse transcription polymerase chain reaction (RT-PCR), but PCR can have limited availability. Here, we propose a combination of a tunable peptide substrate and gold nanoparticles (AuNPs) to colorimetrically detect the Southampton norovirus 3C-like protease (SV3CP), a key protease in viral replication. Careful design of the substrate employs a zwitterionic peptide with opposite charged moieties on the C- and N- termini to induce a rapid color change visible to the naked eye; thus, this color change is indicative of SV3CP activity. This work expands on existing zwitterionic peptide strategies for protease detection by systematically evaluating the effects of lysine and arginine on nanoparticle charge screening. We also determine a limit of detection for SV3CP of 28.0 nM with comparable results in external breath condensate, urine, and fecal matter for 100 nM of SV3CP. The key advantage of this system is its simplicity and accessibility, thus making it an attractive tool for qualitative point-of-care diagnostics.


Assuntos
Infecções por Caliciviridae , Nanopartículas Metálicas , Norovirus , Humanos , Peptídeo Hidrolases , Norovirus/genética , Ouro , Colorimetria , Peptídeos , Endopeptidases , Fezes , Infecções por Caliciviridae/diagnóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa
20.
ACS Nano ; 17(17): 16980-16992, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37579082

RESUMO

Better insights into the fate of membraneless organelles could strengthen the understanding of the transition from prebiotic components to multicellular organisms. Compartmentalized enzyme reactions in a synthetic coacervate have been investigated, yet there remains a gap in understanding the enzyme interactions with coacervate as a substrate hub. Here, we study how the molecularly crowded nature of the coacervate affects the interactions of the embedded substrate with a protease. We design oligopeptide-based coacervates that comprise an anionic Asp-peptide (D10) and a cationic Arg-peptide (R5R5) with a proteolytic cleavage site. The coacervates dissolve in the presence of the main protease (Mpro) implicated in the coronavirus lifecycle. We capitalize on the condensed structure, introduce a self-quenching mechanism, and model the enzyme kinetics by using Cy5.5-labeled peptides. The determined specificity constant (kcat/KM) is 5817 M-1 s-1 and is similar to that of the free substrate. We further show that the enzyme kinetics depend on the type and quantity of dye incorporated into the coacervates. Our work presents a simple design for enzyme-responsive coacervates and provides insights into the interactions between the enzyme and coacervates as a whole.


Assuntos
Peptídeos , Proteínas , Peptídeos/química , Oligopeptídeos , Peptídeo Hidrolases
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