Effects on the STAT3-shRNA in Non-Small-Cell Lung Cancer Therapy: Design, Induction of Apoptosis, and Conjugation with Chitosan-Based Gene Vectors

STAT3 plays a particularly important role in several cancer-related signal transduction pathways.Silencing STAT3 via RNA interference or small molecule inhibitors induces the apoptosis of tumor cells,thereby inhibiting the growth of the tumors.In this study,short-hairpin RNA sequences targeting the STAT3 genes were designed,synthesized,and then connected to pGPU6/GFP/Neo plasmids as the shRNA-expression vectors.The expression of STAT3-shRNA was analyzed by real-time PCR,western blotting,and cell apoptosis assay to study the growth and apoptosis of the cells.Then,the effect of STAT3 knockdown on the NCI-H1650 cells was studied in a tumor mouse model.The results revealed that,after an in vitro transfection,the proliferation of NCI-H1650 cells was inhibited,and the cells were induced to apoptosis.The mRNA and protein expression levels of STAT3 were downregulated in the STAT3-shRNA group.In vivo,the tumor mass and volume in the STAT3-shRNA group were significantly lower than in the other two groups.Both the in vivo and in vitro results demonstrated a long-period inhibiting effect on NSCLC,especially in vivo,when the tumor inhibition rate could reach 50%in the STAT3-shRNA group,which is an exciting outcome.Moreover,the study of the conjugation of STAT3-shRNA and chitosan-based vectors revealed that they could be combined steadily with good cytocompati-bility and transfection efficiency.These results together provide convincing evidence for the application of STAT3-shRNA used in the treatment of non-small lung cancer,which could be a promoting prospect for the development of gene therapy.

Cationic content effects of biodegradable amphoteric chitosan-based flocculants on the flocculation properties

A series of biodegradable amphoteric chitosan-based flocculants （3-chloro-2-hydroxypropyl trimethyl ammonium chloride （CTA） modified carboxymethyl chitosan, denoted as CMC-CTA） with different substitution degrees of CTA were prepared successfully. The content of carboxymethyl groups in each CMC-CTA sample was kept almost constant. The solubility of the various flocculants showed that, higher cationic content of flocculants caused a better solubility. The flocculation experiments using kaolin suspension as synthetic water at the laboratory scale indicated that the substitution degree of CTA was one of the key factors for the flocculation properties. With the increase of cationic content, the flocculants were demonstrated better flocculation performance and lower dosage requirement. Flocculation kinetics model of particles collisions combining zeta potential and turbidity measurements was employed to investigate the effects of the cationic content of the flocculants on the flocculation properties from the viewpoint of flocculation mechanism in detail. Furthermore, flocculation performance using raw water from Zhenjiang part of Yangtze River at the pilot scale showed the similar effects to those at the laboratory scale.

Fluorescence "turn-on" Sensing Platform for Glutathione Detection Using Chitosan-Based Glutaraldehyde Non-conjugated Polymers

We established a f uorescence“turn-on”sensing platform for glutathione(GSH)detection utilizing chitosan-based glutaraldehyde non-conjugated polymers(GCPF)as nanomaterials via f uorescence resonance energy transfer(FRET)principle.Owing to the overlapping property of absorption spectrum of MnO^(2)nanosheets with f uorescence spectrum of GCPF,f uorescent intensity of GCPF was quenched in the presence of MnO^(2)nanosheets because of FRET principle.When GSH was added,MnO^(2)nanosheets were reduced and decomposed into large amounts of Mn^(2+)ions owing to reducing property of GSH.Accordingly,the quenched f uorescent intensity was turned on again.Therefore,this platform based on MnO^(2)nanosheet has been f rst applied to f uorescence“turn-on”detection of GSH from 0.5 to 50μmol/L with sdetection limit of 84 nmol/L.It showed high selectivity in GSH detection towards other ions and biomolecules such as L-lysine,L-threonine,L-valine,L-glutamic acid and DL-aspartic acid.When it was utilized in detecting GSH in serum samples,satisfactory recoveries ranged from 101.5%to 103.2%,indicating the accuracy of this f uorescence“turn-on”platform in bioanalysis.

壳聚糖基纤维止血效果研究(英文)

[目的]探讨壳聚糖基纤维对肝脏的止血效果。[方法]建立兔肝脏出血模型。试验组使用壳聚糖基纤维贴敷创面,对照组使用速即纱,空白组不使用任何材料。术后观察止血效果,记录各组的总出血量和止血率。[结果]试验组在观察期无出血现象,止血率为100%,出血量为(0.443±0.030)g/kg,显著优于对照组和空白组(P<0.05)。[结论]壳聚糖基纤维对肝脏创面止血效果显著,为进一步开展临床试验提供了依据。

Novel chitosan-ethylene glycol hydrogel for the removal of aqueous perfluorooctanoic acid

It is urgent to explore an effective removal method for perfluorooctanoic acid(PFOA)due to its recalcitrant nature.In this study,a novel chitosan-based hydrogel(CEGH)was prepared with a simple method using chitosan and ethylene glycol through a repeated freezingthawing procedure.The adsorption of PFOA anions to CEGH agreed well to the FreundlichLangmuir model with a maximum adsorption capacity as high as 1275.9 mg/g,which is higher than reported values of most adsorbents for PFOA.The adsorption was influenced by experimental conditions.Experimental results showed that the main removal mechanism was the ionic hydrogen bond interaction between carbonyl groups(COO-)of PFOA and protonated amine(NH^+)of the CEGH adsorbent.Therefore,CEGH is a very attractive adsorbent that can be used to remove PFOA from water in the future.

Proteomic profiling reveals engineered chitosan nanoparticles mediated cellular crosstalk and immunomodulation for therapeutic application in apical periodontitis

Macrophages(MQ)are major constituents of chronically inflamed periapical tissues in apical periodontitis.This study aimed to investigate the immunomodulatory effect of engineered bioactive chitosan-based nanoparticles(CSnp)antibiofilm medication on MQ cocultured with periodontal ligament fibroblasts(PdLF).Cells viability,spreading,PdLF migration,and intracellular CSnp uptake were characterized.Tandem Mass Tag-based proteomics was applied to analyze MQ global protein expression profiles after interaction with Enterococcus faecalis biofilm,CSnp-treated biofilm,and CSnp.Secreted inflammatory mediators were analyzed.Following bioinformatics analyses,candidate proteins were validated via targeted proteomics.CSnp maintained cells viability,increased MQ spreading,and PdLF migration(p<0.05).Transmission electron micrographs demonstrated CSnp internalization via macropinocytosis,clathrin-mediated endocytosis,and phagocytosis.Proteomic analysis revealed that CSnp-treated biofilm upregulated proteins(>1.5-folds,p<0.05)showed functional enrichment in the pathway of metal sequestration by antimicrobial proteins,while downregulated proteins showed enrichment in ferroptosis.CSnp upregulated proteins exhibiting antioxidant and immunoregulatory properties.Upregulation of SERPINB1 by CSnp(>1.5-folds,p<0.05)was validated.CSnp-treated biofilm reduced pro-inflammatory IL-1β and nitric oxide but enhanced anti-inflammatory IL-10 and TGF-β1(p<0.05).Internalized engineered bioactive CSnp reprogrammed MQ proteomic and cytokine profiles to modulate biofilm-mediated inflammation,and prompted PdLF migration,emphasizing its potential to regulate healing process in the treatment of apical periodontitis.

Antibacterial chitosan-Dioscorea alata starch film enriched with essential oils optimally prepared by following response surface methodology

Numerous endeavours have been developed bio-based polymer packaging films to replace the use of petroleum-based packaging.In this study,as a response and support to the enduring research issues,we have developed the optimization composite film formulation based on chitosan(2%),Dioscorea alata starch(0.5%),and glycerol(1.5%)had satisfactory result on several parameters consisting thickness(0.45 mm),solubility(472.1%),moisture content(29.872%),biodegradability(38.346%),elastic modulus(971.2 N/m2)and tensile strength(98.71 N/m).Further,the optimized chitosan film(CF)formulation was enriched with several essential oils(EO),i.e.,lemongrass,garlic and aloe vera oil.Upon the addition of EO,the solubility,biodegradable tests,and elongation to break of CF tended to decrease whereas the contact angle and mechanical properties significantly increased.Finally,the antibacterial properties of CF against Escherichia coli,Salmonella typhi,Staphylococcus aureus and Staphylococcus epidermidis dramatically increased by the addition of EO.These impressive results are expected to be applied in the food packaging industry to maintain the quality of food products.