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1.
J Mater Chem B ; 12(16): 3947-3958, 2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38586917

ABSTRACT

Colorectal cancer (CRC) occurs in the colorectum and ranks second in the global incidence of all cancers, accounting for one of the highest mortalities. Although the combination chemotherapy regimen of 5-fluorouracil (5-FU) and platinum(IV) oxaliplatin prodrug (OxPt) is an effective strategy for CRC treatment in clinical practice, chemotherapy resistance caused by tumor-resided Fusobacterium nucleatum (Fn) could result in treatment failure. To enhance the efficacy and improve the biocompatibility of combination chemotherapy, we developed an antibacterial-based nanodrug delivery system for Fn-associated CRC treatment. A tumor microenvironment-activated nanomedicine 5-FU-LA@PPL was constructed by the self-assembly of chemotherapeutic drug derivatives 5-FU-LA and polymeric drug carrier PPL. PPL is prepared by conjugating lauric acid (LA) and OxPt to hyperbranched polyglycidyl ether. In principle, LA is used to selectively combat Fn, inhibit autophagy in CRC cells, restore chemosensitivity of 5-FU as well as OxPt, and consequently enhance the combination chemotherapy effects for Fn-associated drug-resistant colorectal tumor. Both in vitro and in vivo studies exhibited that the tailored nanomedicine possessed efficient antibacterial and anti-tumor activities with improved biocompatibility and reduced non-specific toxicity. Hence, this novel anti-tumor strategy has great potential in the combination chemotherapy of CRC, which suggests a clinically relevant valuable option for bacteria-associated drug-resistant cancers.


Subject(s)
Antineoplastic Agents , Colorectal Neoplasms , Fluorouracil , Lauric Acids , Fluorouracil/pharmacology , Fluorouracil/chemistry , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/pathology , Humans , Lauric Acids/chemistry , Lauric Acids/pharmacology , Animals , Mice , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Fusobacterium nucleatum/drug effects , Oxaliplatin/pharmacology , Oxaliplatin/chemistry , Drug Delivery Systems , Cell Proliferation/drug effects , Drug Screening Assays, Antitumor , Prodrugs/chemistry , Prodrugs/pharmacology , Biocompatible Materials/chemistry , Biocompatible Materials/pharmacology , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Mice, Inbred BALB C , Particle Size , Drug Carriers/chemistry
3.
Nat Chem Biol ; 2024 Jan 29.
Article in English | MEDLINE | ID: mdl-38287154

ABSTRACT

Synchronized ferroptosis contributes to nephron loss in acute kidney injury (AKI). However, the propagation signals and the underlying mechanisms of the synchronized ferroptosis for renal tubular injury remain unresolved. Here we report that platelet-activating factor (PAF) and PAF-like phospholipids (PAF-LPLs) mediated synchronized ferroptosis and contributed to AKI. The emergence of PAF and PAF-LPLs in ferroptosis caused the instability of biomembranes and signaled the cell death of neighboring cells. This cascade could be suppressed by PAF-acetylhydrolase (II) (PAFAH2) or by addition of antibodies against PAF. Genetic knockout or pharmacological inhibition of PAFAH2 increased PAF production, augmented synchronized ferroptosis and exacerbated ischemia/reperfusion (I/R)-induced AKI. Notably, intravenous administration of wild-type PAFAH2 protein, but not its enzymatically inactive mutants, prevented synchronized tubular cell death, nephron loss and AKI. Our findings offer an insight into the mechanisms of synchronized ferroptosis and suggest a possibility for the preventive intervention of AKI.

4.
Chinese Journal of School Health ; (12): 133-137, 2024.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1011408

ABSTRACT

Objective@#To explore the pattern of change of axial length/curvatrue radius ratio (AL/CR) and associated factors in primary and secondary school students in Yunnan, so as to provide scientific basis and prospective guidance for early myopia intervention and control.@*Methods@#A total of 685 students from grades 2 to 3 and grade 7 in 2 cities/counties in Yunnan Province were selected by multi stage stratified random cluster sampling method in 2020. All the participants were followed up twice with questionnaire of myopia related factors, uncorrected distance visual acuity, and refractive parameter measurement from October,2021 and March,2023,respectivelty. The distribution and change of AL/CR in different classes and groups were analyzed, and the influencing factos of AL/CR cumulative progression were explored using generalized linear model.@*Results@#AL/CR ratio in primary school students was (2.95±0.09) at baseline, increased to (2.99±0.11) at the first follow up and (3.04±0.12) at the second follow up. AL/CR ratio in middle school students(3.08±0.13) at baseline, increased to (3.12±0.15) at the first follow up and (3.15±0.14) at the second follow up. The generalized linear model showed that after controlling for environmental factors, ethnicity ( β =-0.017) , cumulative progression of the SE ( β =-0.027) influenced the changes of AL/CR ratio among the primary school students, whereas the changes of AL/CR ratio were associated with baseline AL ( β =-0.005), baseline corneal curvatrue radius ( β =0.032) and cumulative progression of SE( β =-0.035) among middle school students ( P <0.05).@*Conclusions@#The AL/CR ratio of primary and secondary school students in Yunnan can be used to judge different refractive status types, but its variation is not only related to SE progression, but also affected by different ethnic groups and baseline ocular biological parameters. so the value of AL/CR application in assessing the progression of myopia needs to be further confirmed.

5.
J Control Release ; 359: 69-84, 2023 07.
Article in English | MEDLINE | ID: mdl-37245723

ABSTRACT

The naturally evolved and intestinal pathogenic Fusobacterium nucleatum (Fn)-induced drug resistance profoundly impaired the efficacy of chemotherapy against colorectal cancer (CRC). Alternative treatment modalities against Fn-associated CRC are desperately needed. Herein, we engineer an in situ-activated anti-tumor and antibacterial nanoplatform (Cu2O/BNN6@MSN-Dex) to allow photoacoustic (PA) imaging-guided photothermal and NO gas combinatorial therapy for enhanced Fn-associated CRC treatment. The nanoplatform is constructed by loading cuprous oxide (Cu2O) and nitric oxide (NO) donor (BNN6) into dextran-decorated mesoporous silica nanoparticles (MSN), which is finally surface-functionalized with dextran via dynamic boronate linkage. Cu2O can be sulfuretted in situ by endogenous hydrogen sulfide overexpressed in CRC to produce copper sulfide with remarkable PA and photothermal properties, enabling the generation of NO from BNN6 under 808 nm laser irradiation, which is eventually triggered to release by multiple biological cues in the tumor microenvironment. Cu2O/BNN6@MSN-Dex exhibits superior biocompatibility, as well as H2S-triggered near-infrared-controlled antibacterial and anti-tumor performance in vitro and in vivo via photothermal and NO gas combination therapy. Furthermore, Cu2O/BNN6@MSN-Dex provokes systemic immune responses, thereby promoting anti-tumor efficacy. This study provides a conbinational strategy to effectively inhibit tumors and intratumor pathogens for enhanced CRC treatment.


Subject(s)
Colorectal Neoplasms , Nanoparticles , Humans , Nitric Oxide , Copper , Dextrans , Phototherapy , Silicon Dioxide , Nitric Oxide Donors , Anti-Bacterial Agents/pharmacology , Colorectal Neoplasms/drug therapy , Nanoparticles/therapeutic use , Tumor Microenvironment
6.
Small ; 17(29): e2101180, 2021 07.
Article in English | MEDLINE | ID: mdl-34145754

ABSTRACT

Photodynamic therapy (PDT), which utilizes photosensitizer to convert molecular oxygen into singlet oxygen (1 O2 ) upon laser irradiation to ablate tumors, will exacerbate the already oxygen shortage of most solid tumors and is thus self-limiting. Herein, a sophisticated photosensitive polymeric material (An-NP) that allows sustained 1 O2 generation and sufficient oxygen supply during the entire phototherapy is engineered by alternatively applying PDT and photothermal therapy (PTT) controlled by two NIR laser beams. In addition to a photosensitizer that generates 1 O2 , An-NP consists of two other key components: a molecularly designed anthracene derivative capable of trapping/releasing 1 O2 with superior reversibility and a dye J-aggregate with superb photothermal performance. Thus, in 655 nm laser-triggered PDT process, An-NP generates abundant 1 O2 with extra 1 O2 being trapped via the conversion into EPO-NP; while in the subsequent 785 nm laser-driven PTT process, the converted EPO-NP undergoes thermolysis to liberate the captured 1 O2 and regenerates An-NP. The intratumoral oxygen level can be replenished during the PTT cycle for the next round of PDT to generate 1 O2 . The working principle and phototherapy efficacy are preliminarily demonstrated in living cells and tumor-bearing mice, respectively.


Subject(s)
Photochemotherapy , Singlet Oxygen , Animals , Cell Line, Tumor , Mice , Photosensitizing Agents/therapeutic use , Phototherapy
7.
ACS Nano ; 15(3): 5032-5042, 2021 03 23.
Article in English | MEDLINE | ID: mdl-33635051

ABSTRACT

The design of organic photothermal agents (PTAs) for in vivo applications face a demanding set of performance requirements, especially intense NIR-absorptivity and sufficient photobleaching resistance. J-aggregation offers a facile way to tune the optical properties of dyes, thus providing a general design platform for organic PTAs with the desired performance. Herein, we present a supramolecular strategy to build a water-stable, nonphotobleaching, and NIR-absorbing nano-PTA (J-NP) from J-aggregation of halogenated BODIPY dyes (BDP) for efficient in vivo photothermal therapy. Multiple intermolecular halogen-bonding and π-π stacking interactions triggered the formation of BDP J-aggregate, which adsorbed amphiphilic polymer chains on the surface to provide PEGylated sheetlike nano-J-aggregate (J-NS). We serendipitously discovered that the architecture of J-NS was remodeled during a long-time ultrafiltration process, generating a discrete spherical nano-J-aggregate (J-NP) with controlled size. Compared with J-NS, the remodeled J-NP significantly improved cellular uptake efficiency. J-aggregation brought J-NP striking photothermal performance, such as strong NIR-absorptivity, high photothermal conversion efficiency up to 72.0%, and favorable nonphotobleaching ability. PEGylation and shape-remodeling imparted by the polymer coating enabled J-NP to hold biocompatibility and stability in vivo, thereby exhibiting efficient antitumor photothermal activities. This work not only presents a facile J-aggregation strategy for preparing PTAs with high photothermal performance but also establishes a supramolecular platform that enables the appealing optical functions derived from J-aggregation to be applied in vivo.


Subject(s)
Photothermal Therapy , Polymers , Cell Line, Tumor , Photobleaching , Phototherapy
8.
Biosens Bioelectron ; 175: 112866, 2021 Mar 01.
Article in English | MEDLINE | ID: mdl-33272867

ABSTRACT

Marring the reversible covalent chemistry with BODIPY dye, which is a superfamily of fluorophores with striking photophysical performances, would enable a panel of diverse dynamic fluorescent probes for biomedical applications. Herein we show that structural manipulation of BODIPY allows rational tuning of α-site or meso-site activation as well as the spectral response toward nucleophiles. By rational molecular design, we have obtained a highly specific and reversible GSH probe, αBD-GSH, which exhibits a tremendously fast and dynamic fluorescence response within the wide physiological GSH concentration range of 0-8 mM. We successfully applied αBD-GSH to real-time imaging of intracellular GSH dynamics in different cell lines. In light of the remarkable photophysical properties and synthesis flexibility of BODIPY dyes, the current findings will help to design more reversible BODIPY-based fluorescent probes targeting various bio-species.


Subject(s)
Biosensing Techniques , Fluorescent Dyes , Boron Compounds , HeLa Cells , Humans
9.
J Clin Hypertens (Greenwich) ; 22(4): 623-630, 2020 04.
Article in English | MEDLINE | ID: mdl-32153115

ABSTRACT

The purpose of this study was to assess the association of blood pressure (BP) measurements with the risk of cardiovascular disease (CVD) and examine whether central systolic BP (CSBP) predicts CVD better than brachial BP measurements (SBP and pulse pressure [PP]). Based on a cross-sectional study conducted in 2009-2010 with follow-up in 2016-2017 among 35- to 64-year-old subjects in China, we evaluated the performance of non-invasively predicted CSBP over brachial BP measurements on the first CVD events. Each BP measurement, individually and jointly with another BP measurement, was entered into the multivariate Cox proportional-hazards models, to examine the predictability of central and brachial BP measurements. Mean age of participants (n = 8710) was 50.1 years at baseline. After a median follow-up of 6.36 years, 187 CVD events occurred. CSBP was a stronger predictor for CVD than brachial BP measurements (CSBP, 1-standard deviation increment HR = 1.49, 95%CI: 1.31-1.70). With CSBP and SBP entering into models jointly, the HR for CSBP and SBP was 1.28 (1.04-1.58) and 1.22 (0.98-1.50), respectively. With CSBP and PP entering into models jointly, the HR for CSBP and PP was 1.51 (1.28-1.78) and 0.98 (0.83-1.15), respectively. For subgroup analysis, the association of CSBP with CVD was stronger than brachial BP measurements in women, those with hypertension and obesity. In the middle-aged Chinese population, noninvasively estimated CSBP may offer advantages over brachial BP measurements to predict CVD events, especially for participants with higher risk. These findings suggest prospective assessment of CSBP as a prevention and treatment target in further trials.


Subject(s)
Cardiovascular Diseases , Adult , Blood Pressure , Blood Pressure Determination , Cardiovascular Diseases/diagnosis , Cardiovascular Diseases/epidemiology , China/epidemiology , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Prospective Studies , Risk Factors
10.
Chemistry ; 26(20): 4505-4509, 2020 Apr 06.
Article in English | MEDLINE | ID: mdl-32077546

ABSTRACT

Dye assemblies exhibit fascinating properties and performances, both of which depend critically on the mutual packing arrangement of dyes and on the supramolecular architecture. Herein, we engineered, for the first time, an intriguing chlorosome-mimetic 2D crystalline J-dimer lamellar structure based on halogenated dyes in aqueous media by employing two distinct orthogonal halogen-bonding (XB) interactions. As the only building motif, antiparallel J-dimer was formed and stabilized by single π-stacking and dual halogen⋅⋅⋅π interactions. With two substituted halogen atoms acting as XB donors and the other two acting as acceptors, the constituent J-dimer units were linked by quadruple highly-directional halogen⋅⋅⋅halogen interactions in a staggered manner, resulting in unique 2D lamellar dye assemblies. This work champions and advances halogen-bonding as a remarkably potent tool for engineering dye aggregates with a controlled molecular packing arrangement and supramolecular architecture.

11.
J Am Chem Soc ; 141(1): 402-413, 2019 01 09.
Article in English | MEDLINE | ID: mdl-30547576

ABSTRACT

Controlling the packing arrangements of dyes is a facile way of tuning their photophysical and/or photochemical properties, thus enabling new sensing mechanisms for photofunctional tools. Here, we present a general and robust strategy toward water-stable J-aggregated dye-templated nanoassemblies by incorporating an amphiphilic diblock copolymer and a stimuli-responsive dye as the only two building components. An iodo-substituted boron dipyrromethene (BODIPY) was adopted as a template to direct the self-assembly of poly(ethylene glycol)- block-polycaprolactone (PEG-PCL), forming a core-shell nanoplate with slip-stacked BODIPYs as core surrounded by hydrophilic PEG shell. The self-assembled nanoplate is stable in cell culture medium and possesses a built-in stimuli-responsiveness that arises from BODIPY bearing meso-carboxylate protecting group, which is efficiently removed upon treatment with peroxynitrite. The resulting negative charges lead to rearrangement of dyes from J-stacking to nonstacking, which activates photoinduced singlet oxygen production from the nanoassemblies. The stimuli-activatable photosensitivity has been exploited for specific photodynamic ablation of activated RAW 264.7 cells with excessive endogenous peroxynitrite. In light of the generality of the sensing mechanism, the concept described herein will significantly expand the palette of design principles to develop diverse photofunctional tools for biological research and clinical needs.


Subject(s)
Coloring Agents/chemistry , Nanostructures/chemistry , Boron Compounds/chemistry , Hydrophobic and Hydrophilic Interactions , Lactones/chemistry , Models, Molecular , Molecular Conformation , Photosensitizing Agents/chemistry , Polyethylene Glycols/chemistry
12.
J Am Chem Soc ; 139(29): 10157-10163, 2017 07 26.
Article in English | MEDLINE | ID: mdl-28654288

ABSTRACT

A general approach toward highly fluorogenic probes across the visible spectrum for various analytes offers significant potential for engineering a wide range of bioprobes with diverse sensing and imaging functions. Here we show a facile and general strategy that involves introducing a new fluorogenic mechanism in boron dipyrromethene (BODIPY) dyes, based on the principle of stimuli-triggered dramatic reduction in the electron-withdrawing capabilities of the meso-substituents of BODIPYs. The fluorogenic mechanism has been demonstrated to be applicable in various BODIPYs with emission maxima ranging from green to far red (509, 585, and 660 nm), and the synthetic strategy allows access to a panel of highly fluorogenic bioprobes for various biomolecules and enzymes (H2O2, H2S, and protease) via introducing specific triggering motifs. The potency of the general design strategy is exemplified by its application to develop a mitochondria-targeting far-red probe capable of imaging of endogenous H2O2 in living cells.


Subject(s)
Biosensing Techniques , Boron Compounds/chemistry , Fluorescent Dyes/chemistry , Hydrogen Peroxide/analysis , Optical Imaging , Peptide Hydrolases/analysis , Porphobilinogen/analogs & derivatives , Boron Compounds/pharmacology , Cell Survival , Electrons , Fluorescent Dyes/pharmacology , HeLa Cells , Humans , Mitochondria/chemistry , Mitochondria/metabolism , Molecular Structure , Peptide Hydrolases/metabolism , Porphobilinogen/chemistry , Porphobilinogen/pharmacology , Spectrometry, Fluorescence , Spectrophotometry, Ultraviolet
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