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1.
Proc Natl Acad Sci U S A ; 119(4)2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35042819

RESUMO

Inspired by the intriguing adaptivity of natural life, such as squids and flowers, we propose a series of dynamic and responsive multifunctional devices based on multiscale structural design, which contain metal nanocoating layers overlaid with other micro-/nanoscale soft or rigid layers. Since the optical/photothermal properties of a metal nanocoating are thickness dependent, metal nanocoatings with different thicknesses were chosen to integrate with other structural design elements to achieve dynamic multistimuli responses. The resultant devices demonstrate 1) strain-regulated cracked and/or wrinkled topography with tunable light-scattering properties, 2) moisture/photothermal-responsive structural color coupled with wrinkled surface, and 3) mechanically controllable light-shielding properties attributed to the strain-dependent crack width of the nanocoating. These devices can adapt external stimuli, such as mechanical strain, moisture, light, and/or heat, into corresponding changes of optical signals, such as transparency, reflectance, and/or coloration. Therefore, these devices can be applied as multistimuli-responsive encryption devices, smart windows, moisture/photothermal-responsive dynamic optics, and smartphone app-assisted pressure-mapping sensors. All the devices exhibit high reversibility and rapid responsiveness. Thus, this hybrid system containing ultrathin metal nanocoatings holds a unique design flexibility and adaptivity and is promising for developing next-generation multifunctional devices with widespread application.

2.
Environ Res ; 248: 118324, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38301759

RESUMO

BACKGROUND: There are various methods to assess interaction effects. However, current methods have limitations, and quantification of interaction effects is rarely performed. This study aimed to develop a unified quantitative framework for assessing interaction effects. METHODS: We proposed a novel framework using log-linear models with a product term(s) across the exposures that generates parametric bi-variate association and interaction effect surfaces and allows flexible functional forms for exposures in the interaction term(s). In a case study, we assessed the interaction effects between temperature and air pollution (i.e., PM2.5, NO2, and O3) on risk for kidney-related conditions in New York State (2007-2016) using a case-crossover design with conditional logistic models. Our measures of exposure were the moving averages at lag 0-5 days for air pollution (linear) and daytime mean outdoor wet-bulb globe temperature (WBGT; using a natural cubic spline). RESULTS: We derived closed-form expressions for the magnitude of multiplicative interaction effects (the joint relative risk divided by the product of the two conditional relative risks) and their uncertainties. In the case study, we found a Bonferroni-corrected significant multiplicative interaction effect (IE) between outdoor WBGT at the 99th percentile (median as the reference) and (1) PM2.5 (per 5 µg/m3 increase, IE = 1.052; 95 % confidence interval [CI]: 1.019, 1.087) for acute kidney failure and (2) O3 (per 5 ppb increase; IE = 1.022; 95 % CI: 1.008, 1.036) for urolithiasis (the latter being inconclusive based on the sensitivity analysis). CONCLUSIONS: Our framework allows different functional forms of exposure variables in the interaction term, quantifies the magnitudes of entire-exposure-range (in addition to discrete exposure level) multiplicative interaction effects and their uncertainties in a categorical or continuous (linear or non-linear) manner, and harmonizes the two-way evaluation of effect modification. The case study underscores co-consideration of heat and air pollution when estimating health burden and designing heat/pollution alert systems.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Nefropatias , Humanos , Poluentes Atmosféricos/análise , Temperatura , New York , Poluição do Ar/análise , Exposição Ambiental/análise , Estudos Epidemiológicos , Material Particulado/análise , Rim , Dióxido de Nitrogênio/análise
3.
Catheter Cardiovasc Interv ; 101(6): 1062-1070, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36934416

RESUMO

OBJECTIVES: In this study, we aimed to investigate the vascular response to an intravascular lithotripsy (IVL) shockwave balloon in a healthy porcine coronary artery model. BACKGROUND: IVL is a novel clinical technique for modifying heavily calcified atherosclerotic plaques. METHODS: A total of 24 porcine coronary arteries were treated with IVL or plain old balloon angioplasty (POBA). Histology, histomorphometry, quantitative coronary angiography analysis (QCA), and optical coherence tomography (OCT) were performed postprocedure and at 1-month follow-up (1M-FU). RESULTS: There was no significant difference in the late lumen loss and diameter stenosis (determined by QCA) and the minimal lumen area (evaluated by OCT) of the IVL and POBA groups at 1M-FU. Pathological analysis revealed that the lumen and neointima areas were similar between the two groups. However, the medial and adventitial layers were more prominent in the IVL than in the POBA group. The injury score and inflammation of the media and adventitia increased dramatically in the IVL group postprocedure and at 1M-FU. At 1M-FU, media fibrin deposition and adventitial fibrosis were also significantly increased in the IVL group. However, there was no significant difference in neointima fibrin deposition, endothelialization, and thrombosis between both groups. Layered separation of the media and adventitia was observed in the IVL group. CONCLUSION: The findings indicate that the IVL balloon did not cause serious intimal hyperplasia and endothelial damage compared with the effects of POBA in the healthy coronary artery. However, shock waves may cause unique damage to the vascular media and adventitia in the coronary artery, which was not observed in the peripheral artery.


Assuntos
Angioplastia Coronária com Balão , Litotripsia , Suínos , Animais , Neointima , Resultado do Tratamento , Angioplastia Coronária com Balão/métodos , Litotripsia/efeitos adversos , Fibrina
4.
Small ; 18(48): e2204759, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36285744

RESUMO

In order to artificially regulate cell behaviors, intracellular polymerization as an emerging chemical technique has attracted much attention. Yet, it is still a challenge to achieve effective intracellular polymerization to conquer tumors in the complex cellular environment. Herein, this work develops a tumor-targeting and caspase-3 responsive nanoparticle composed of a diacetylene-containing lipidated peptide amphiphile and mitochondria-targeting photosensitizer (C3), which undergoes nanoparticle-to-nanofiber transformation and efficient in situ polymerization triggered by photodynamic treatment and activation of caspase-3. The locational nanofibers on the mitochondria membranes lead to mitochondrial reactive oxygen species (mtROS) burst and self-amplified circulation, offering persistent high oxidative stress to induce cell apoptosis. This study provides a strategy for greatly enhanced antitumor therapeutic efficacy through mtROS burst and self-amplified circulation induced by intracellular transformation and in situ polymerization.


Assuntos
Fotoquimioterapia , Fármacos Fotossensibilizantes , Caspase 3 , Polimerização , Linhagem Celular Tumoral , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Peptídeos
5.
Macromol Rapid Commun ; 43(18): e2200176, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35451187

RESUMO

Bacterial infection can delay wound healing, causing wounds to deteriorate and even threaten the patient's life. Recently, although many composite hydrogels as wound dressing have been developed, it is still highly desired to construct photothermal hydrogels with antimicrobial and antioxidant properties to accelerate the infected wound healing. In this work, a hyaluronic acid (HA)-based composite hydrogel consisting of a dopamine-substituted antimicrobial peptide (DAP) and Iron (III) ions is developed, which exhibits photothermal-assisted promotion and acceleration of healing process of bacteria-infected wounds. DAP, serving as both antimicrobial agent and ROS-scavenger, forms Schiff's base bonds with aldehyde hyaluronic acid (AHA) and iron-catechol coordination bonds to reinforce the composite hydrogel. The presence of Fe3+ can also promote covalent polymerization of dopamine, which endows the hydrogel with photothermal capacity. The in vitro and in vivo experiments prove that the composite hydrogel can effectively accelerate the infected wound healing process, including antibacterial, accelerated collagen deposition, and re-epithelization. This study suggests that the multifunctional composite hydrogel possesses remarkable potential for bacteria-infected wound healing by combining inherent antimicrobial activity, antioxidant capability, and photothermal effect.


Assuntos
Anti-Infecciosos , Hidrogéis , Adesivos/química , Aldeídos , Antibacterianos/química , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Peptídeos Antimicrobianos , Antioxidantes/química , Antioxidantes/farmacologia , Catecóis , Colágeno , Dopamina , Humanos , Ácido Hialurônico/química , Ácido Hialurônico/farmacologia , Hidrogéis/química , Hidrogéis/farmacologia , Íons , Ferro , Espécies Reativas de Oxigênio , Cimentos de Resina , Cicatrização
6.
Lifetime Data Anal ; 27(4): 679-709, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34215947

RESUMO

In medical studies, the collected covariates contain underlying outliers. For clustered/longitudinal data with censored observations, the traditional Gehan-type estimator is robust to outliers in response but sensitive to outliers in the covariate domain, and it also ignores the within-cluster correlations. To take account of within-cluster correlations, varying cluster sizes, and outliers in covariates, we propose weighted Gehan-type estimating functions for parameter estimation in the accelerated failure time model for clustered data. We provide the asymptotic properties of the resulting estimators and carry out simulation studies to evaluate the performance of the proposed method under a variety of realistic settings. The simulation results demonstrate that the proposed method is robust to the outliers existing in the covariate domain and lead to much more efficient estimators when a strong within-cluster correlation exists. Finally, the proposed method is applied to two medical datasets and more reliable and convincing results are hence obtained.


Assuntos
Projetos de Pesquisa , Causalidade , Simulação por Computador , Humanos
7.
Analyst ; 145(17): 5826-5835, 2020 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-32648860

RESUMO

The development of inexpensive, selective and rapid-response chemosensors for detecting Cs+ in waste water is highly desirable in the nuclear power industry. Here we demonstrate an efficient Cs+ optical sensor based on the N-linked disalicylaldehyde H2Qj with excited state intramolecular proton transfer (ESIPT), and it will transform into the ligand-to-metal charge transfer (LMCT) process in the presence of Cs+, resulting in dramatically enhanced fluorescence together with a distinct change of color from light-green to green-yellow. Simultaneously, it is found that CH2Cl2 can serve as the quencher of LMCT-enhanced fluorescence, thus enabling selective CH2Cl2 detection in a turn-off fluorescence approach. Further detailed studies reveal that both Cs+ and CH2Cl2 sensing processes are rapid within 60 seconds. The corresponding limit of detection (LOD) values for sensing Cs+ and CH2Cl2 are as low as 0.37 mM and 0.37%. Moreover, it was also verified that Cs+ sensing is applicable in the range of pH = 7-11 and the reversibility of sensor H2Qj can be easily achieved by modulating pH values, and H2Qj is also assessed for its Cs+ sensing performces in real water samples. This H2Qj-Cs sensing system must provide a valuable reference for further Cs+ sensors.

8.
Analyst ; 144(17): 5254-5260, 2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31364615

RESUMO

In this paper we report a novel probe based on a luminescent 23-membered [1 + 1] Schiff-base macrocyclic mononuclear Sm(iii) complex Sm-2e, originating from the dialdehyde H2Qe and 1,2-bis(2-aminoethoxy)ethane precursors, which is synthesized by the Sm(iii) ion template method. X-ray structural analyses confirm that each ten-coordinate Sm(iii) center with the coordination geometry of a distorted bicapped square antiprism is fully encapsulated by a flexible macrocyclic ligand H2L2e to form a "lasso-type" architecture, and this architecture could enable efficient energy transfer in various solvents confirmed by long lifetimes (33.5-65.2 µs) and high quantum yields (0.23-0.76%) of the Sm(iii) ion. Simultaneously, complex Sm-2e could serve as a probe for sensing organic solvents. Particularly, this complex probe Sm-2e exhibits a highly selective, rapid and sensitive response to tetrahydrofuran (THF), which is easily distinguished by a large absorption shift, even visible to the naked eye, and complete fluorescence quenching. Moreover, the limit of detection for THF is about 0.20% determined by titration experiments, and good selectivity for THF could still be realized in mixture solvents. Consequently, this colorimetric and "turn off" fluorescent probe Sm-2e could be a valuable candidate as a sensor material for sensing THF which has been rarely reported.


Assuntos
Complexos de Coordenação/química , Corantes Fluorescentes/química , Furanos/análise , Colorimetria/métodos , Complexos de Coordenação/síntese química , Fluorescência , Corantes Fluorescentes/síntese química , Limite de Detecção , Samário/química , Bases de Schiff/síntese química , Bases de Schiff/química , Espectrometria de Fluorescência/métodos
9.
Int J Biol Macromol ; 257(Pt 1): 128636, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38065459

RESUMO

Injectable hydrogel has attracted appealing attention for skin wound treatment. Although multifunctional injectable hydrogels can be prepared by introducing bioactive ingredients with antibacterial and anti-inflammatory capabilities, their preparation remains complicated. Herein, a polyphenol-based supramolecular injectable hydrogel (PBSIH) based on polyphenol gallic acid and biological macromolecule sodium alginate is developed as a wound dressing to accelerate wound healing. We show that such PBSIH can be rapidly formed within 15 s by mixing the sodium alginate and gallic acid solutions based on the hydrogen bonding and hydrophobic interactions. The PBSIH shows excellent cytocompatibility, antibacterial, and antioxidant properties, which enhance infected wound healing by inhibiting bacterial infection and alleviating inflammation after treatment of 11 days. Moreover, we show that the preparative strategies of injectable supramolecular hydrogels can be extended to other polyphenols, including protocatechuic and tannic acids. This study provides a facile yet highly effective method to design injectable polyphenol- sodium alginate hydrogel for wound dressing based on naturally bioactive ingredients.


Assuntos
Hidrogéis , Cicatrização , Anti-Inflamatórios/farmacologia , Antibacterianos/farmacologia , Alginatos , Ácido Gálico/farmacologia , Veículos Farmacêuticos , Polifenóis/farmacologia
10.
IEEE Trans Pattern Anal Mach Intell ; 46(2): 1199-1211, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37903051

RESUMO

Offline reinforcement learning (RL) harnesses the power of massive datasets for resolving sequential decision problems. Most existing papers only discuss defending against out-of-distribution (OOD) actions while we investigate a broader issue, the false correlations between epistemic uncertainty and decision-making, an essential factor that causes suboptimality. In this paper, we propose falSe COrrelation REduction (SCORE) for offline RL, a practically effective and theoretically provable algorithm. We empirically show that SCORE achieves the SoTA performance with 3.1x acceleration on various tasks in a standard benchmark (D4RL). The proposed algorithm introduces an annealing behavior cloning regularizer to help produce a high-quality estimation of uncertainty which is critical for eliminating false correlations from suboptimality. Theoretically, we justify the rationality of the proposed method and prove its convergence to the optimal policy with a sublinear rate under mild assumptions.

11.
J Colloid Interface Sci ; 663: 1074-1086, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38331692

RESUMO

Drug-resistant biofilm infection is an extremely serious clinical problem, that easily leads to failure of antibiotic treatment. Although gold nanoparticles (AuNPs) as photothermal agents have been widely used in biofilm eradication, there are still challenges to be addressed, such as insignificantly redshifted absorption and slow assembly process of aggregated AuNPs. Herein, we developed an acidity-activated dispersion-to-aggregation transition to enhance the accumulation of self-complementary zwitterionic peptide-decorated AuNPs for photothermal eradication of drug-resistant biofilm infections. AuNPs were decorated with self-complementary zwitterionic peptides (ZP1 and ZP2) coupled with pH-sensitive anhydride (DMA) and pH-insensitive anhydride (SA), respectively. ZP2-decorated AuNPs with DMA modification (AuNP@ZP2(DMA)) exhibited prolonged blood circulation and enhanced accumulation in acidic biofilm microenvironment. Moreover, the electrostatic attraction between self-complementary ligands drove AuNPs to form closely packed aggregates with strong near-infrared absorption, leading to in vivo photoacoustic imaging ability and photothermal effect against drug-resistant bacteria and fungus, as well as microbial biofilms. AuNP@ZP2(DMA) with longer charge domains and a polyethylene glycol oligomer spacer showed greater photothermal antimicrobial and biofilm resistance in vitro and in vivo. This study develops an innovative acidity-activated AuNP photothermal agent, which provides an effective approach for treatment of biofilm infections.


Assuntos
Ouro , Nanopartículas Metálicas , Ouro/farmacologia , Ouro/química , Nanopartículas Metálicas/química , Antibacterianos/farmacologia , Antibacterianos/química , Biofilmes , Anidridos/farmacologia
12.
Nat Commun ; 15(1): 2038, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448448

RESUMO

Hypertrophic scar (HS) considerably affects the appearance and causes tissue dysfunction in patients. The low bioavailability of 5-fluorouracil poses a challenge for HS treatment. Here we show a separating microneedle (MN) consisting of photo-crosslinked GelMA and 5-FuA-Pep-MA prodrug in response to high reactive oxygen species (ROS) levels and overexpression of matrix metalloproteinases (MMPs) in the HS pathological microenvironment. In vivo experiments in female mice demonstrate that the retention of MN tips in the tissue provides a slowly sustained drug release manner. Importantly, drug-loaded MNs could remodel the pathological microenvironment of female rabbit ear HS tissues by ROS scavenging and MMPs consumption. Bulk and single cell RNA sequencing analyses confirm that drug-loaded MNs could reverse skin fibrosis through down-regulation of BCL-2-associated death promoter (BAD), insulin-like growth factor 1 receptor (IGF1R) pathways, simultaneously regulate inflammatory response and keratinocyte differentiation via up-regulation of toll-like receptors (TOLL), interleukin-1 receptor (IL1R) and keratinocyte pathways, and promote the interactions between fibroblasts and keratinocytes via ligand-receptor pair of proteoglycans 2 (HSPG2)-dystroglycan 1(DAG1). This study reveals the potential therapeutic mechanism of drug-loaded MNs in HS treatment and presents a broad prospect for clinical application.


Assuntos
Cicatriz Hipertrófica , Humanos , Animais , Feminino , Camundongos , Coelhos , Cicatriz Hipertrófica/tratamento farmacológico , Espécies Reativas de Oxigênio , Disponibilidade Biológica , Diferenciação Celular , Metaloproteinases da Matriz
13.
Micromachines (Basel) ; 14(11)2023 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-38004970

RESUMO

The task of the detection of unmanned aerial vehicles (UAVs) is of great significance to social communication security. Infrared detection technology has the advantage of not being interfered with by environmental and other factors and can detect UAVs in complex environments. Since infrared detection equipment is expensive and data collection is difficult, there are few existing UAV-based infrared images, making it difficult to train deep neural networks; in addition, there are background clutter and noise in infrared images, such as heavy clouds, buildings, etc. The signal-to-clutter ratio is low, and the signal-to-noise ratio is low. Therefore, it is difficult to achieve the UAV detection task using traditional methods. The above challenges make infrared UAV detection a difficult task. In order to solve the above problems, this work drew upon the visual processing mechanism of the human brain to propose an effective framework for UAV detection in infrared images. The framework first determines the relevant parameters of the continuous-coupled neural network (CCNN) through the image's standard deviation, mean, etc. Then, it inputs the image into the CCNN, groups the pixels through iteration, then obtains the segmentation result through expansion and erosion, and finally, obtains the final result through the minimum circumscribed rectangle. The experimental results showed that, compared with the existing most-advanced brain-inspired image-understanding methods, this framework has the best intersection over union (IoU) (the intersection over union is the overlapping area between the predicted segmentation and the label divided by the joint area between the predicted segmentation and the label) in UAV infrared images, with an average of 74.79% (up to 97.01%), and can effectively realize the task of UAV detection.

14.
J Am Stat Assoc ; 118(544): 2315-2328, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38550788

RESUMO

In this paper, we leverage over-parameterization to design regularization-free algorithms for the high-dimensional single index model and provide theoretical guarantees for the induced implicit regularization phenomenon. Specifically, we study both vector and matrix single index models where the link function is nonlinear and unknown, the signal parameter is either a sparse vector or a low-rank symmetric matrix, and the response variable can be heavy-tailed. To gain a better understanding of the role played by implicit regularization without excess technicality, we assume that the distribution of the covariates is known a priori. For both the vector and matrix settings, we construct an over-parameterized least-squares loss function by employing the score function transform and a robust truncation step designed specifically for heavy-tailed data. We propose to estimate the true parameter by applying regularization-free gradient descent to the loss function. When the initialization is close to the origin and the stepsize is sufficiently small, we prove that the obtained solution achieves minimax optimal statistical rates of convergence in both the vector and matrix cases. In addition, our experimental results support our theoretical findings and also demonstrate that our methods empirically outperform classical methods with explicit regularization in terms of both ℓ2-statistical rate and variable selection consistency.

15.
Cardiooncology ; 9(1): 39, 2023 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-37924143

RESUMO

BACKGROUND: Percutaneous left atrial appendage occlusion (LAAO) has been rapidly evolving since FDA's approval in 2015 and has become more of a same-day-discharge procedure. Cancer patient with atrial fibrillation/flutter (AF) population can benefit from the procedure but the in-hospital outcomes and readmission data were rarely studied. OBJECTIVES: We investigated the utilization, in-hospital and readmission outcomes in cancer patients with AF who underwent LAAO. METHODS: Data were derived from the National Inpatient Sample and National Readmissions Database from 2016 to 2019. Patients with primary diagnosis of AF admitted for LAAO (ICD-10 code 02L73DK) were grouped by cancer as a secondary diagnosis. We assessed in-hospital mortality, length of stay, total hospital charges, and complications. Thirty-day readmission rates were compared. RESULTS: LAAO was performed in 60,380 patients with AF and 3% were cancer patients. There were no differences in in-hospital mortality and total hospital charges; however, cancer patients tended to have longer hospital stay (1.59 ± 0.11 vs. 1.32 ± 0.02, p = 0.013). Among complications, cancer patients had higher rates in open or percutaneous pericardial drainage (adjusted odds ratio [aOR] 2.38; 95% confidence interval [CI] 1.19-4.76) and major bleeding events (aOR 7.07; 95% CI 1.82-27.38). There was no statistical significance of 30-day readmission rates between patients with and without cancer (10.0% vs. 9.1%, p = 0.34). The most common readmission reason in cancer patients was gastrointestinal bleeding. CONCLUSIONS: LAAO is a promising procedure in cancer patients complicated by AF with contraindication to anticoagulation. Readmission rate is comparable between patients with and without cancer.

16.
Adv Healthc Mater ; 12(18): e2203092, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36907173

RESUMO

Ferroptosis has recently attracted much attention as an anti-tumor therapy. Evidence suggests that ferroptosis can induce oxidative stress and accumulation of lethal lipid peroxides in cancer cells, leading to cell damage. However, unsuitable pH, H2 O2 levels, and high glutathione (GSH) expression in the tumor microenvironment hinder the development of ferroptosis-mediated therapy. In this study, an l-arginine (l-arg)-modified CoWO4 /FeWO4 (CFW) S-scheme heterojunction is strategically designed and constructed for ultrasound (US)-triggered sonodynamic- and gas therapy-induced ferroptosis. CFW not only has excellent Fenton-catalytic activity, outstanding GSH consumption capacity, and excellent ability to overcome tumor hypoxia, but its S-scheme heterostructure can also avoid the rapid combination of electron (e) and hole (h+ ) pairs, thereby enhancing the sonodynamic effects. As a precursor of nitric oxide (NO), l-arg is modified on the surface of CFW (CFW@l-arg) to achieve controlled NO release under US irradiation, thereby enhancing ferroptosis. In addition, poly(allylamine hydrochloride) is further modified on the surface of CFW@l-arg to stabilize l-arg and achieve controllable NO release. Both in vitro and in vivo results demonstrate that such a multifunctional therapeutic nanoplatform can achieve high therapeutic efficacy through sonodynamic and gas therapy-enhanced ferroptosis. This designed oncotherapy nanoplatform provides new inspiration for ferroptosis-mediated therapy.


Assuntos
Ferroptose , Neoplasias , Humanos , Arginina/farmacologia , Glutationa , Peróxidos Lipídicos , Óxido Nítrico , Linhagem Celular Tumoral , Espécies Reativas de Oxigênio , Microambiente Tumoral
17.
Macromol Biosci ; : e2300451, 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-37997560

RESUMO

Antimicrobial peptides (AMPs) potentially serve as ideal antimicrobial agents for the treatment of polymicrobial abdominal infections due to their broad-spectrum antimicrobial activity and excellent biocompatibility. However, the balance of chain length, positive charges, and hydrophobicity on the antimicrobial activity of AMPs are still far from being optimal. Herein, a series of AMPs ([KX]n -NH2 , X = Ile, Leu or Phe, n = 3, 4, 5, or 6) with varied charges and hydrophobicity for the treatment of polymicrobial abdominal infections are designed. Specifically, [KI]4 -NH2 peptide exhibits the best in vitro antimicrobial activity against Gram-positive and -negative bacteria, as well as fungal strains. Based on the good cell biocompatibility, [KI]4 -NH2 peptide is found to have negligible in vivo toxicity at the dosage of up to 28 mg kg-1 . Furthermore, great in vivo therapeutic efficacy of [KI]4 -NH2 peptide against S. typhimurium is demonstrated in the mice abdominal infection model. The design of short sequence of antimicrobial peptides with a charge/hydrophobicity balanced structures provides a simple and efficient strategy for potential clinical applications of antimicrobial peptide-based biomaterials in a variety of bacterial infection diseases.

18.
Int J Biol Macromol ; 199: 234-242, 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-34998888

RESUMO

In this study, the magnetic chitosan biochar (MCB) was magnetized by chemical coprecipitation after loading chitosan with Schiff base reaction. The prepared MCB was used to remove amaranth dye in solution. The synthesized MCB was characterized to define its surface morphology and specific elements. The amaranth dye adsorption system was optimized by varying the contact time, pH, and initial concentration. The adsorption of MCB on amaranth dye was measured in a wide pH range. According to Zeta potential, the surface of MCB was positively charged in the acidic pH region, which was more conducive to the adsorption of anionic amaranth dye. In addition, the adsorption data was fitted with the pseudo-first-order model and Langmuir adsorption model and the maximum adsorption capacity reached 404.18 mg/g. The adsorption efficiency of MCB was still above 95% after three cycles of adsorption and desorption. The removal percentage in the real sample of amaranth dye by MCB was within 94.5-98.6% and the RSD was within 0.14-1.08%. The MCB adsorbent with advantages of being easy to prepare, easy to separate from solution after adsorption, has good adsorption performance for amaranth dye and is effective potential adsorbent to remove organic anionic dye in wastewater.


Assuntos
Quitosana , Poluentes Químicos da Água , Adsorção , Corante Amaranto , Carvão Vegetal , Quitosana/química , Concentração de Íons de Hidrogênio , Cinética , Fenômenos Magnéticos , Poluentes Químicos da Água/química , Zea mays
19.
J Appl Stat ; 49(14): 3677-3692, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36246863

RESUMO

Variable selection is fundamental to high dimensional statistical modeling, and many approaches have been proposed. However, existing variable selection methods do not perform well in presence of outliers in response variable or/and covariates. In order to ensure a high probability of correct selection and efficient parameter estimation, we investigate a robust variable selection method based on a modified Huber's function with an exponential squared loss tail. We also prove that the proposed method has oracle properties. Furthermore, we carry out simulation studies to evaluate the performance of the proposed method for both pn. Our simulation results indicate that the proposed method is efficient and robust against outliers and heavy-tailed distributions. Finally, a real dataset from an air pollution mortality study is used to illustrate the proposed method.

20.
ACS Macro Lett ; 11(2): 223-229, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35574773

RESUMO

Precise control of diacetylene-containing peptide amphiphile (DPA) based supramolecular architectures is important for their in cellulo polymerization behaviors and biomedical applications. Herein, we reported two DPAs (cationic PA-NH2 and zwitterionic PA-OH) with a similar molecular structure, which exhibited completely opposite polymerization behaviors in aqueous solution and living cells. Specifically, PA-NH2 was unpolymerizable in aqueous solution but underwent in cellulo polymerization to respond to the intracellular microenvironment. On the contrary, zwitterionic PA-OH was polymerized in solution, rather than inside living cells. Based on the results of cell viability and total internal reflection fluorescent microscopy measurement, PA-OH exhibited higher affinity with cell membranes and lower cytotoxicity than those of PA-NH2. Therefore, it is suggested that the in cellulo polymerization of PA-NH2 should be responsive for greater cytotoxicity, rather than the membrane affinity. This study provides an in-depth understanding of the role of charge properties in the polymerization behavior of DPAs and seeks their potential biomedical applications.


Assuntos
Peptídeos , Água , Estrutura Molecular , Peptídeos/química , Polimerização , Água/química
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