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1.
Acta Biomater ; 2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38838905

ABSTRACT

Anti-angiogenesis has emerged a promising strategy against colorectal cancer (CRC). However, the efficacy of anti-angiogenic therapy is greatly compromised by the up-regulated autophagy levels resulting from the evolutionary resistance mechanism and the presence of Fusobacterium nucleatum (F. nucleatum) in CRC. Herein, we report a cationic polymer capable of blocking autophagic flux to deliver plasmid DNA (pDNA) encoding soluble FMS-like tyrosine kinase-1 (sFlt-1) for enhanced anti-angiogenic therapy against F. nucleatum-associated CRC. The autophagy-inhibiting cationic polymer, referred to as PNHCQ, is synthesized by conjugating hydroxychloroquine (HCQ) into 3,3'-diaminodipropylamine-pendant poly(ß-benzyl-L-aspartate) (PAsp(Nors)), which can be assembled and electrostatically interacted with sFlt-1 plasmid to form PNHCQ/sFlt-1 polyplexes. Hydrophobic HCQ modification not only boosts transfection efficiency but confers autophagy inhibition activity to the polymer. Hyaluronic acid (HA) coating is further introduced to afford PNHCQ/sFlt-1@HA for improved tumor targeting without compromising on transfection. Consequently, PNHCQ/sFlt-1@HA demonstrates significant anti-tumor efficacy in F. nucleatum-colocalized HT29 mouse xenograft model by simultaneously exerting anti-angiogenic effects through sFlt-1 expression and down-regulating autophagy levels exacerbated by F. nucleatum challenge. The combination of anti-angiogenic gene delivery and overall autophagy blockade effectively sensitizes CRC tumors to anti-angiogenesis, providing an innovative approach for enhanced anti-angiogenic therapy against F. nucleatum-resident CRC. STATEMENT OF SIGNIFICANCE: Up-regulated autophagy level within tumors is considered responsible for the impaired efficacy of clinic antiangiogenic therapy against CRC colonized with pathogenic F. nucleatum. To tackle this problem, an autophagy-inhibiting cationic polymer is developed to enable efficient intracellular delivery of plasmid DNA encoding soluble FMS-like tyrosine kinase-1 (sFlt-1) and enhance anti-angiogenic therapy against F. nucleatum-associated CRC. HA coating that can be degraded by tumor-enriching hyaluronidase is further introduced for improved tumor targeting without compromising transfection efficiency. The well-orchestrated polyplexes achieve considerable tumor accumulation, efficient in vivo transfection, and effectively reinforce the sensitivity of CRC to the sFlt-1-derived anti-angiogenic effects by significantly blocking overall autophagy flux exacerbated by F. nucleatum challenge, thus harvesting robust antitumor outcomes against F. nucleatum-resident CRC.

2.
J Math Biol ; 88(6): 77, 2024 May 02.
Article in English | MEDLINE | ID: mdl-38695878

ABSTRACT

A dynamic reaction-diffusion model of four variables is proposed to describe the spread of lytic viruses among phytoplankton in a poorly mixed aquatic environment. The basic ecological reproductive index for phytoplankton invasion and the basic reproduction number for virus transmission are derived to characterize the phytoplankton growth and virus transmission dynamics. The theoretical and numerical results from the model show that the spread of lytic viruses effectively controls phytoplankton blooms. This validates the observations and experimental results of Emiliana huxleyi-lytic virus interactions. The studies also indicate that the lytic virus transmission cannot occur in a low-light or oligotrophic aquatic environment.


Subject(s)
Basic Reproduction Number , Eutrophication , Mathematical Concepts , Models, Biological , Phytoplankton , Phytoplankton/virology , Phytoplankton/growth & development , Phytoplankton/physiology , Basic Reproduction Number/statistics & numerical data , Haptophyta/virology , Haptophyta/growth & development , Haptophyta/physiology , Computer Simulation
3.
Sci Rep ; 14(1): 10211, 2024 May 03.
Article in English | MEDLINE | ID: mdl-38702439

ABSTRACT

In order to study the failure mode and fracture evolution characteristics of red shale in Kaiyang Phosphorus mining area, conventional triaxial compression mechanical tests of red shale with different bedding dip angles were carried out by using DSTD-1000 electro-hydraulic servo rock mechanics experiment system. Based on the laboratory test results, the conventional triaxial particle flow simulation of red shale samples with different bedding dip angles was carried out using discrete element PFC2D. The results show that: (1) the failure mode of red shale is controlled by bedrock when the bedding dip angle is 0° and 60° ~ 90°. When the bedding dip angle is 15° ~ 45°, the rock failure mode is controlled by bedding. The compressive strength of rock is the minimum when the bedding dip angle is 30°and the maximum at 0°, which is about 2 times of the minimum. (2) In the failure process of red shale, the cracks with different bedding dip angles show slow growth stage, accelerated growth stage and stable stage with axial strain. The whole failure process is dominated by tensile cracks, accompanied by a few shear cracks. (3) The type of displacement field varies with the bedding dip angle: tensile failure and shear failure are the main displacement field types at 15° ~ 45°, and mixed failure is often the main mode at 60° ~ 90°and 0°. The research results provide the basis and reference for the safety control of red shale roadway.

4.
Medicine (Baltimore) ; 103(14): e37635, 2024 Apr 05.
Article in English | MEDLINE | ID: mdl-38579067

ABSTRACT

Depressive symptoms are frequently occur among dentistry patients, many of whom struggle with dental anxiety and poor oral conditions. Identifying the factors that influence these symptoms can enable dentists to recognize and address mental health concerns more effectively. This study aimed to investigate the factors associated with depressive symptoms in dentistry patients and develop a clinical tool, a nomogram, to assist dentists in predicting these symptoms. Methods: After exclusion of ineligible participants, a total of 1355 patients from the dentistry department were included. The patients were randomly assigned to training and validation sets at a 2:1 ratio. The LASSO regression method was initially employed to select highly influrtial features. This was followed by the application of a multi-factor logistic regression to determine independent factors and construct a nomogram. And it was evaluated by 4 methods and 2 indicators. The nomograms were formulated based on questionnaire data collected from dentistry patients. Nomogram2 incorporated factors such as medical burden, personality traits (extraversion, conscientiousness, and emotional stability), life purpose, and life satisfaction. In the training set, Nomogram2 exhibited a Concordance index (C-index) of 0.805 and an Area Under the Receiver Operating Characteristic Curve (AUC) of 0.805 (95% CI: 0.775-0.835). In the validation set, Nomogram2 demonstrated an Area Under the Receiver Operating Characteristic Curve (AUC) of 0.810 (0.768-0.851) and a Concordance index (C-index) of 0.810. Similarly, Nomogram1 achieved an Area Under the Receiver Operating Characteristic Curve (AUC) of 0.816 (0.788-0.845) and a Concordance index (C-index) of 0.816 in the training set, and an Area Under the Receiver Operating Characteristic Curve (AUC) of 0.824 (95% CI: 0.784-0.864) and a Concordance index (C-index) of 0.824 in the validation set. Net Reclassification Improvement (NRI) and Integrated Discrimination Improvement (IDI) indicated that Nomogram1, which included oral-related factors (oral health and dental anxiety), outperformed Nomogram2. We developed a nomogram to predict depressive symptoms in dentistry patients. Importantly, this nomogram can serve as a valuable psychometric tool for dentists, facilitating the assessment of their patients' mental health and enabling more tailored treatment plans.


Subject(s)
Depression , Nomograms , Humans , Cross-Sectional Studies , Depression/diagnosis , Emotions , Dentistry , Prognosis
5.
Small Methods ; 8(3): e2301309, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38018349

ABSTRACT

Fusobacterium nucleatum (Fn) existing in the community of colorectal cancer (CRC) promotes CRC progression and causes chemotherapy resistance. Despite great efforts that have been made to overcome Fn-induced chemotherapy resistance by co-delivering antibacterial agents and chemotherapeutic drugs, increasing the drug-loading capacity and enabling controlled release of drugs remain challenging. In this study, a novel supramolecular upconversion nanoparticle (SUNP) is constructed by incorporating a positively charged polymer (PAMAM-LA-CD) with Fn inhibition capacity, a negatively charged platinum (IV) oxaliplatin prodrug (OXA-COOH), upconversion nanoparticle (UCNPs) and polyethylene glycol-azobenzene (PEG-Azo) to enhance drug-loading and enable on-demand drug release for drug-resistant CRC treatment. SUNPs exhibit high drug-loading capacity (30.8%) and good structural stability under normal physiological conditions, while disassembled upon exogenous NIR excitation and endogenous azo reductase in the CRC microenvironment to trigger drug release. In vitro and in vivo studies demonstrate that SUNPs presented good biocompatibility and robust performance to overcome chemoresistance, thereby significantly inhibiting Fn-infected cancer cell proliferation. This study leverages multiple dynamic chemical designs to integrate both advantages of drug loading and release in a single system, which provides a promising candidate for precision therapy of bacterial-related drug-resistant cancers.


Subject(s)
Colorectal Neoplasms , Fusobacterium nucleatum , Humans , Fusobacterium nucleatum/physiology , Colorectal Neoplasms/drug therapy , Nanomedicine , Tumor Microenvironment
6.
Math Biosci ; 368: 109134, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38158013

ABSTRACT

A dynamic model is proposed to describe a mycoloop in aquatic food webs. The model consists of phytoplankton, chytrids and zooplankton. It characterizes that zooplankton consume both phytoplankton and free-living chytrid spores, and that chytrids infect phytoplankton. The dynamics of the model are investigated containing the dissipativity, existence and stability of equilibria, and persistence. The ecological reproductive indexes for phytoplankton or zooplankton invasion and basic reproduction numbers for chytrid transmission are derived. The parameter values of the model are estimated based on experimental data. Numerical simulations explore the effects of the mycoloop on phytoplankton blooms and chytrid transmission. This research reveals that the mycoloop structure increases or reduces phytoplankton blooms, and controls the spread of chytrids among phytoplankton.


Subject(s)
Food Chain , Phytoplankton , Animals , Zooplankton
7.
Lupus ; 32(14): 1598-1609, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37903189

ABSTRACT

BACKGROUND: Cuproptosis is a novel mode of cell death, which is strongly related to energy metabolism in mitochondria and regulated by protein lipoylation. Currently, the molecular mechanisms of cuproptosis-related genes (CRGs) involved in systemic lupus erythematosus (SLE) largely remained unclear, our study is aimed to explore the mechanisms of cuproptosis and CRGs involved in SLE. METHODS: Bulk RNA-seq datasets were collected to display the expressions of CRGs in peripheral blood mononuclear cells (PBMCs) of SLE and healthy individuals, and then ROC analysis was used to establish the diagnostic models of CRGs. Next, the immune infiltration analyses were applied to reveal the difference of immune cells infiltration in LIAS-low and LIAS-high group. Additionally, WGCNA analysis was performed to find the gene modules significantly correlated with the LIAS expression level. We also performed the functional enrichment analyses for LIAS-related gene modules to determine the potential pathways involved in the development of SLE. Finally, scRNA-seq dataset was used to cluster immune cell subsets, reveal the activated pathways, and study cell-cell interactions in LIAS-low and LIAS-high cells. RESULT: We found CDKN2A was significantly increased and LIAS was significantly decreased in SLE patients compared with healthy individuals. The AUC score showed that LIAS had a great diagnostic value than other CRGs. Additionally, the results of immune infiltration analyses showed that immune cells proportion were diverse in LIAS-low and LIAS-high samples. The gene sets related to LIAS expression level were involved in dephosphorylation of JAK1 by SHP1, phosphorylation of STAT2, cytokine signaling in immune system, expression of interferon-alpha and beta, inhibition of JAK kinase activity by SOCS1/3, and so on. Finally, the results of cell-cell communication showed that CCL- (CCL5 + CCR1) and ANNEXIN- (ANXA1 + FPR1) might play an essential role in the communication network between LIAS-low and LIAS-high cells. CONCLUSION: Above findings inferred that LIAS-mediated cuproptosis might involve in a comprehensive cellular and molecular mechanism to cause the occurrence and development of SLE.


Subject(s)
Apoptosis , Leukocytes, Mononuclear , Lupus Erythematosus, Systemic , Sulfurtransferases , Humans , Cell Communication , Copper , Gene Regulatory Networks , Lupus Erythematosus, Systemic/genetics , Phosphorylation , Sulfurtransferases/genetics
8.
Polymers (Basel) ; 15(18)2023 Sep 14.
Article in English | MEDLINE | ID: mdl-37765621

ABSTRACT

In this paper, a polyacrylic elastomer latex with butyl acrylate (BA) as the core and methyl methacrylate (MMA) copolymerized with glycidyl methacrylate (GMA) as the shell, named poly(BA-MMA-GMA) (PBMG), was synthesized by seeded emulsion polymerization. Cellulose nanocrystal (CNC) was dispersed in the polyacrylic latex to prepare PBMG/CNC dispersions with different CNC contents. The dried product was mixed with polylactic acid (PLA) to fabricate PLA/PBMG/CNC blends. The addition of PBMG and PBMG/CNC improved the mechanical properties of the PLA matrix. Differential scanning calorimetry (DSC) was used to investigate the non-isothermal crystallization kinetics. The Avrami equation modified by the Jeziorny, Ozawa and Mo equations was used to analyze the non-isothermal crystallization kinetics of PLA and its blends. Analysis of the crystallization halftime of non-isothermal conditions indicated that the overall rate of crystallization increased significantly at 1 wt% content of CNC. This seemed to result from the increase of nucleation density and the acceleration of segment movement in the presence of the CNC component. This phenomenon was verified by polarizing microscope observation.

9.
Front Immunol ; 14: 1231047, 2023.
Article in English | MEDLINE | ID: mdl-37638021

ABSTRACT

Rheumatoid arthritis (RA) is a painful and incurable disease characterized by chronic joint inflammation and a progressive destruction of cartilage and bone. Although current treatments have improved clinical outcomes for some patients, the high relapse rates and sizeable proportion of non-responders emphasize the need for further research. Arthritic joints are massively infiltrated by neutrophils, which influence inflammatory and immune processes by releasing cytokines, chemokines, eicosanoids, and neutrophil serine proteases (NSPs) - all of which are known to contribute to RA initiation and progression. Active NSPs are generated from zymogens at the promyelocytic stage of neutrophil differentiation under the action of dipeptidyl peptidase 1 (DPP-1) and DPP-1 knockout mice are resistant to the development of arthritis. Thus, DPP-1 inhibition represents a promising therapeutic approach in RA. In this study, we assessed the efficacy of a potent and highly selective DPP-1 inhibitor, brensocatib, in two well established RA models - rat collagen-induced arthritis (CIA) and mouse collagen antibody-induced arthritis (CAIA). In both models, brensocatib at 3 and 30 mg/kg/day significantly reduced bone marrow NSP levels, in keeping with prior pharmacodynamic studies in rodents. More importantly, brensocatib treatment significantly improved disease score at both dosages in both rodent models. In the mouse CAIA model, brensocatib even proved at least as potent as anti-TNF antibodies in diminishing both the histopathological score and neutrophil infiltration into arthritic joints. Together, these results show that brensocatib alters RA disease progression in rodents and supports the need for its further evaluation as a potential therapeutic option, or to complement existing RA treatments.


Subject(s)
Arthritis, Experimental , Arthritis, Rheumatoid , Animals , Mice , Rats , Tumor Necrosis Factor Inhibitors , Arthritis, Rheumatoid/drug therapy , Disease Models, Animal , Antibodies , Arthritis, Experimental/drug therapy , Dipeptidyl-Peptidases and Tripeptidyl-Peptidases , Disease Progression
10.
BMC Complement Med Ther ; 23(1): 287, 2023 Aug 14.
Article in English | MEDLINE | ID: mdl-37580684

ABSTRACT

OBJECTIVES: Diabetic Nephropathy (DN) is a serious complication of diabetes, the diagnosis and treatment of DN is still limited. Sinomenine (SIN) is an active extract of herbal medicine and has been applied into the therapy of DN. METHODS: In the part of bioinformatic analyses, network pharmacology and molecular docking analyses were conducted to predict the important pathway of SIN treatment for DN. In-vivo study, DN rats were randomized to be treated with vehicle or SIN (20 mg/kg or 40 mg/kg) daily by gavage for 8 weeks. Then, the pharmacological effect of SIN on DN and the potential mechanisms were also evaluated by 24 h albuminuria, histopathological examination, transcriptomics, and metabolomics. RESULTS: Firstly, network pharmacology and molecular docking were performed to show that SIN might improve DN via AGEs/RAGE, IL-17, JAK, TNF pathways. Urine biochemical parameters showed that SIN treatment could significantly reduce 24 h albuminuria of DN rats. Transcriptomics analysis found SIN could affect DN progression via inflammation and EMT pathways. Metabolic pathway analysis found SIN would mainly involve in arginine biosynthesis, linoleic acid metabolism, arachidonic acid metabolism, and glycerophospholipid metabolism to affect DN development. CONCLUSIONS: We confirmed that SIN could inhibit the progression of DN via affecting multiple genes and metabolites related pathways.


Subject(s)
Diabetes Mellitus , Diabetic Nephropathies , Animals , Rats , Albuminuria , Computational Biology , Diabetic Nephropathies/drug therapy , Molecular Docking Simulation , Multiomics
11.
Math Biosci Eng ; 20(7): 12750-12771, 2023 May 31.
Article in English | MEDLINE | ID: mdl-37501465

ABSTRACT

Intraguild predation is a common ecological phenomenon that manifests itself by the aggression of one predator by another to obtain a shared prey species. In this paper, we develop a discrete analog of a stoichiometric continuous-time intraguild predation model. We analyze the dynamics of the discrete-time model, such as boundedness and invariance, stability of equilibria, and features of ecological matrices. The dynamic behavior of the two models is compared and analyzed through numerical analysis. We observe the same coexistence region of populations and stoichiometric effects of food quality of the shared prey in both models. Obvious differences between the discrete- and continuous-time models can be observed with intermediate and high levels of light intensity. The multistability characteristics and the existence interval of chaos differ among the different time scale models. This study provides evidence of the importance of time scales on intraguild predation.

12.
Front Immunol ; 14: 1185727, 2023.
Article in English | MEDLINE | ID: mdl-37441081

ABSTRACT

Neutrophils have been implicated in initiating and perpetuating systemic lupus erythematosus and the resultant kidney damage in lupus nephritis (LN) patients, in part through an excessive release of neutrophil serine proteases (NSPs). NSP zymogens are activated by dipeptidyl peptidase 1 (DPP1) during neutrophil maturation and released by mature neutrophils in response to inflammatory stimuli. Thus, a potential strategy to attenuate disease progression in LN would be to inhibit DPP1. We tested whether brensocatib, a highly selective and reversible DPP1 inhibitor, could mitigate LN progression in an interferon-alpha (IFNα)-accelerated NZB/W F1 mouse model. To confirm brensocatib's pharmacodynamic effect on NSPs in this mouse strain, repeated dose studies were conducted for 7 and 14 days in naïve NZB/W F1 mice via oral gavage twice a day. Brensocatib at 2 and 20 mg/kg/day achieved a significant reduction in bone marrow NSP activities after 7 days of daily administration. To initiate LN disease progression, the mice were injected with an IFNα-expressing adenovirus. After 2 weeks, three brensocatib doses (or vehicle) were administered for 6 more weeks. Throughout the 8-week study, brensocatib treatment (20 mg/kg/day) significantly reduced the occurrence of severe proteinuria compared to the vehicle control. Brensocatib treatment also entailed a significant reduction in the urine albumin-to-creatinine ratio, indicating decreased kidney damage, as well as a significant reduction in blood urea nitrogen level, suggesting improved renal function. Based on kidney histopathology analysis, brensocatib treatment significantly lowered both the renal tubular protein score and the nephropathy score compared to the vehicle group. A trend towards reduced glomerulonephritis score with brensocatib treatment was also observed. Lastly, brensocatib significantly reduced LN mouse kidney infiltration by various inflammatory cells. In conclusion, these results suggest that brensocatib alters disease progression in LN mice and warrant further evaluation of DPP1 inhibition in LN.


Subject(s)
Lupus Nephritis , Mice , Animals , Lupus Nephritis/metabolism , Interferon-alpha/pharmacology , Interferon-alpha/therapeutic use , Disease Progression , Dipeptidyl-Peptidases and Tripeptidyl-Peptidases
13.
Respir Res ; 24(1): 133, 2023 May 17.
Article in English | MEDLINE | ID: mdl-37198686

ABSTRACT

BACKGROUND: Brensocatib is an oral, selective, reversible inhibitor of dipeptidyl peptidase-1 (DPP-1), responsible for activating neutrophil serine proteases (NSPs) including neutrophil elastase (NE), proteinase 3 (PR3), and cathepsin G (CatG). In chronic inflammatory lung diseases such as non-cystic fibrosis bronchiectasis (NCFBE), neutrophils accumulate in the airways resulting in excess active NSPs that cause damaging inflammation and lung destruction. METHODS: The 24-week WILLOW trial (NCT03218917) was a randomized, double-blind, placebo-controlled, parallel-group trial in patients with NCFBE conducted at 116 sites across 14 countries. In this trial, treatment with brensocatib was associated with improvements in clinical outcomes including time to first exacerbation, reduction in exacerbation frequency and a reduction in NE activity in sputum. An exploratory analysis of NE activity in white blood cell (WBC) extracts and NE, PR3 and CatG activity in sputum was conducted to further characterize brensocatib's effect and identify potential correlated effects. RESULTS: NE, PR3 and CatG activities were reduced in sputum and NE activity was reduced in WBC extracts in a dose-dependent manner after four weeks of brensocatib treatment, with a return to baseline four weeks after the end of treatment. Brensocatib produced the greatest reduction in the sputum activity of CatG, followed by NE and then PR3. Positive correlations among the sputum NSPs were observed both at baseline and in response to treatment, with the strongest correlation among the sputum NSPs for NE and CatG. CONCLUSIONS: These results suggest a broad anti-inflammatory effect of brensocatib underlying its clinical efficacy observed in NCFBE patients. TRIAL REGISTRATION: The study was approved by the corresponding ethical review boards of all participating centers. The trial was approved by the Food and Drug Administration and registered at clinicaltrials.gov (NCT03218917) on July 17, 2017 and approved by the European Medicines Agency and registered at the European Union Clinical trials Register (EudraCT No. 2017-002533-32). An independent, external data and safety monitoring committee (comprising physicians with pulmonary expertise, a statistician experienced in the evaluation of clinical safety, and experts in periodontal disease and dermatology) reviewed all adverse events.


Subject(s)
Bronchiectasis , Cystic Fibrosis , Salix , Humans , Serine Proteases/pharmacology , Serine Proteases/therapeutic use , Neutrophils , Bronchiectasis/diagnosis , Bronchiectasis/drug therapy , Leukocyte Elastase , Myeloblastin , Dipeptidyl-Peptidases and Tripeptidyl-Peptidases/pharmacology , Dipeptidyl-Peptidases and Tripeptidyl-Peptidases/therapeutic use
14.
Math Biosci Eng ; 20(2): 3983-4005, 2023 01.
Article in English | MEDLINE | ID: mdl-36899613

ABSTRACT

In a shallow aquatic environment, a mathematical model with variable cell quota is proposed to characterize asymmetric resource competition for light and nutrients among aquatic producers. We investigate the dynamics of asymmetric competition models with constant and variable cell quotas and obtain the basic ecological reproductive indexes for aquatic producer invasions. The similarities and differences between the two types of cell quotas for dynamical properties and influences on asymmetric resource competition are explored through theoretical and numerical analysis. These results contribute to further revealing the role of constant and variable cell quotas in aquatic ecosystems.


Subject(s)
Ecosystem , Models, Biological , Nutrients
15.
ACS Appl Mater Interfaces ; 15(10): 12750-12765, 2023 Mar 15.
Article in English | MEDLINE | ID: mdl-36852940

ABSTRACT

The application of photodynamic therapy (PDT) has attracted remarkable interest in cancer treatment because of the advantages of noninvasiveness and spatiotemporal selectivity. However, the PDT efficiency is considerably limited by photosensitizer (PS) quenching and severe hypoxia in solid tumors. Herein, a kind of near infrared (NIR)-activatable methylene blue (MB) peptide nanocarrier was developed for codelivery of nitric oxide (NO) prodrug JSK, expecting a cascade of reactive oxygen species (ROS) amplification-mediated antitumor PDT. In detail, MB was conjugated to water-soluble polyethylene glycol-polylysine (PEG-PLL) through NIR-photocleavable 10-N-carbamoyl bonds, and the subsequent amphiphilic conjugates (mPEG-PLL-MB) self-assembled into nanoparticles (NPs), which allowed JSK codelivery via π-π stacking interactions. MB in quenched state in mPEG-PLL-MB/JSK NPs could be photoactivated by NIR light locoregionally in a controlled manner due to the photocleavage of carbamoyl bonds. Apart from ROS production, assembly disturbance and even disintegration of mPEG-PLL-MB/JSK occurred along with MB activation that subsequently freed JSK, which was further triggered by intracellularly overexpressed glutathione (GSH) and glutathione S-transferase (GST) to sustain the release of NO. NO then served as a hypoxia relief agent through inhibition of cellular respiration to economize O2, cooperating with MB activation and GSH depletion, which synergistically enabled a cascade of ROS amplification to augment PDT for mitochondrial apoptosis-mediated tumor inhibition in vitro and in vivo. Therefore, this pioneering strategy of cascade amplification of ROS addressed the key issues of PS inactivation, hypoxia resistance, and ROS neutralization in a three-pronged approach, which hold great promise in efficient antitumor PDT.


Subject(s)
Nanoparticles , Neoplasms , Photochemotherapy , Prodrugs , Humans , Reactive Oxygen Species , Methylene Blue/pharmacology , Methylene Blue/chemistry , Nitric Oxide , Prodrugs/pharmacology , Photosensitizing Agents/chemistry , Nanoparticles/chemistry , Neoplasms/drug therapy , Peptides/pharmacology , Hypoxia/drug therapy , Cell Line, Tumor
16.
Adv Sci (Weinh) ; 10(11): e2206585, 2023 04.
Article in English | MEDLINE | ID: mdl-36776018

ABSTRACT

Bacterial infection often induces chronic repair of wound healing owing to aggravated inflammation. Hydrogel dressing exhibiting intrinsic antibacterial activity may substantially reduce the use of antibiotics for infected wound management. Hence, a versatile hydrogel dressing (rGB/QCS/PDA-PAM) exhibiting skin adaptiveness on dynamic wounds and  mild photothermal antibacterial activity is developed for safe and efficient infected wound treatment. Phenylboronic acid-functionalized graphene (rGB) and oxadiazole-decorated quaternary carboxymethyl chitosan (QCS) are incorporated into a polydopamine-polyacrylamide (PDA-PAM) network with multiple covalent and noncovalent bonds, which conferred the hydrogel with flexible mechanical properties, strong tissue adhesion and excellent self-healing ability on the dynamic wounds. Moreover, the glycocalyx-mimicking phenylboronic acid on the surface of rGB enables the hydrogel to specifically capture bacteria. The enhanced membrane permeability of QCS enhanced bacterial vulnerability to photothermal therapy(PTT), which is demonstrated by efficient mild PTT antibacteria against methicillin-resistant Staphylococcus aureus in vitro and in vivo at temperatures of <49.6 °C. Consequently, the hydrogel demonstrate accelerated tissue regeneration on MRSA-infected wound in vivo, with an intact epidermis, abundant collagen deposition and prominent angiogenesis. Therefore, rGB/QCS/PDA-PAM is a versatile hydrogel dressing exhibiting inherent antibacterial activity and has considerable potential in treating wounds infected with drug-resistant bacteria.


Subject(s)
Methicillin-Resistant Staphylococcus aureus , Hydrogels , Anti-Bacterial Agents/pharmacology , Bandages , Wound Healing
17.
PLoS One ; 17(8): e0272575, 2022.
Article in English | MEDLINE | ID: mdl-36044421

ABSTRACT

PURPOSE: Neutrophil serine proteases (NSPs) are implicated in numerous inflammatory diseases. Thus, a robust methodology to monitor and quantify NSPs is important to study disease progression and evaluate the effect of pharmacological interventions. A comparison of the various methods used to extract NSPs from neutrophil granulocytes has not been published, providing the impetus to conduct this method optimization and comparison study. METHODS: Two NSP recovery methodologies were evaluated on samples from five human donors: zymosan stimulation and cell pellet extraction. For the zymosan stimulation method, 1 mL donor blood was added to zymosan and samples were incubated at 37°C for 30 min while shaking. Samples were then centrifuged, and the plasma was collected for quantitation of NSP activity. For the cell pellet extraction procedure, 2 mL whole blood samples were centrifuged into white blood cell pellets following red blood cell lysis. To each pellet, three sequential lysis steps were performed using either 0.05% Nonidet P-40 Substitute (NP40) or 0.02% Triton X-100 lysis buffers under agitation followed by centrifugation. NSP activities were quantified using an exogenous peptide substrate specific to each of the three NSPs being analyzed: neutrophil elastase, cathepsin G, and proteinase 3. RESULTS AND DISCUSSION: The zymosan stimulation method resulted in lower recovery of active NSPs and was unable to stimulate significant release of active cathepsin G. In contrast, the NP40 pellet extraction method showed consistent inter-donor NSP release with greater recoveries of active NSPs than the Triton method or the zymosan stimulation method. Overall, the pellet extraction procedure provided 13.3-fold greater recovery of active neutrophil elastase, 283-fold greater recovery of active cathepsin G, and 2.9-fold greater recovery of active proteinase 3 than the zymosan method. CONCLUSION: The NP40 cell pellet extraction method resulted in greater extraction of active NSPs compared to the other methods investigated here, which may allow for a more accurate and complete biomarker profile when evaluating human clinical samples.


Subject(s)
Analytic Sample Preparation Methods , Serine Proteases , Blood Cells/chemistry , Blood Cells/enzymology , Cathepsin G/chemistry , Cathepsin G/metabolism , Humans , Leukocyte Elastase/chemistry , Leukocyte Elastase/metabolism , Myeloblastin , Neutrophils/chemistry , Neutrophils/metabolism , Serine Proteases/chemistry , Serine Proteases/metabolism , Zymosan/pharmacology
18.
J Biol Dyn ; 16(1): 186-206, 2022 12.
Article in English | MEDLINE | ID: mdl-35467465

ABSTRACT

A mathematical model with the intraguild predation structure is proposed to describe the interactions of autotrophs and mixotrophs containing light and nutrients in a well-mixed aquatic ecosystem. The dissipation, existence and stability of equilibria of the model are proved, and the ecological reproductive indexes for the extinction, survival and coexistence of autotrophs and mixotrophs are established. We also consider the influence of Holling type functional responses and abiotic factors on the coexistence and biomass of autotrophs and mixotrophs. It is shown that the intraguild predation structure is beneficial to phytoplankton biodiversity and provides an explanation for the phytoplankton paradox.


Subject(s)
Ecosystem , Predatory Behavior , Animals , Models, Biological , Models, Theoretical , Population Dynamics , Predatory Behavior/physiology
19.
Bull Math Biol ; 84(1): 5, 2021 11 22.
Article in English | MEDLINE | ID: mdl-34807309

ABSTRACT

Autotrophs, mixotrophs and bacteria exhibit complex interrelationships containing multiple ecological mechanisms. A mathematical model based on ecological stoichiometry is proposed to describe the interactions among them. Some dynamic analysis and numerical simulations of this model are presented. The roles of autotrophs and mixotrophs in controlling bacterioplankton are explored to examine the experiments and hypotheses of Medina-Sánchez, Villar-Argaiz and Carrillo for La Caldera Lake. Our results show that the dual control (bottom-up control and top-down control) of bacteria by mixotrophs is a key reason for the ratio of bacterial and phytoplankton biomass in La Caldera Lake to deviate from the general tendency. The numerical bifurcation diagrams suggest that the competition between phytoplankton and bacteria for nutrients can also be an important factor for the decrease of the bacterial biomass in an oligotrophic lake.


Subject(s)
Ecosystem , Models, Biological , Bacteria , Biomass , Mathematical Concepts , Phytoplankton
20.
Macromol Rapid Commun ; 42(21): e2100424, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34505724

ABSTRACT

Amphiphilic graft copolymers exhibit fascinating self-assembly behaviors. Their molecular architectures significantly affect the morphology and functionality of the self-assemblies. Considering the potential application of amphiphilic graft copolymers in the fabrication of nanocarriers, it is essential to synthesize well-defined graft copolymers with desired functional groups. Herein, the Passerini reaction and molecular recognition are introduced to the synthesis of functional thermoresponsive graft copolymers. A bifunctional monomer 2-((adamantan-1-yl)amino)-1-(4-((2-bromo-2-methylpropanoyl)oxy)phenyl)-2-oxoethyl methacrylate (ABMA) with a bromo group for atom transfer radical polymerization (ATRP) and an adamantyl group for molecular recognition is synthesized through the Passerini reaction. The graft copolymers are prepared by reversible addition-fragmentation transfer (RAFT) copolymerization of ABMA and oligo(ethylene glycol) methyl ether methacrylate (OEGMA) followed by RAFT end group removal and ATRP of di(ethylene glycol)methyl ether methacrylate (DEGMA) initiated by the ABMA units. The graft copolymer P(OEGMA-co-ABMA)-g-PDEGMA can be functionalized with ß-cyclodextrin modified peptides, affording a thermoresponsive biohybrid graft copolymer. At a temperature above its lower critical solution temperature, the biohybrid graft copolymer self-assembles into peptide-modified polymersomes.


Subject(s)
Methacrylates , Polymers , Micelles , Polymerization , Temperature
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