Utility of real-time 3D visualization system in the early stage of phacoemulsification training.

AIM: To determine the teaching effects of a real-time three dimensional (3D) visualization system in the operating room for early-stage phacoemulsification training. METHODS: A total of 10 ophthalmology residents of the first-year postgraduate were included. All the residents were novices to cataract surgery. Real-time cataract surgical observations were performed using a custom-built 3D visualization system. The training lasted 4wk (32h) in all. A modified International Council of Ophthalmology's Ophthalmology Surgical Competency Assessment Rubric (ICO-OSCAR) containing 4 specific steps of cataract surgery was applied. The self-assessment (self) and expert-assessment (expert) were performed through the microsurgical attempts in the wet lab for each participant. RESULTS: Compared with pre-training assessments (self 3.2±0.8, expert 2.5±0.6), the overall mean scores of post-training (self 5.2±0.4, expert 4.7±0.6) were significantly improved after real-time observation training of 3D visualization system (P<0.05). Scores of 4 surgical items were significantly improved both self and expert assessment after training (P<0.05). CONCLUSION: The 3D observation training provides novice ophthalmic residents with a better understanding of intraocular microsurgical techniques. It is a useful tool to improve teaching efficiency of surgical education.

Research progress on animal models of corneal epithelial-stromal injury.

A corneal epithelial-stromal defect is recognized as a major contributor to corneal scarring. Given the rising prevalence of blindness caused by corneal scarring, increasing attention has been focused on corneal epithelial-stromal defects. Currently, the etiology and pathogenesis of these defects remain inadequately understood, necessitating further investigation through experimental research. Various modeling methods exist both domestically and internationally, each with distinct adaptive conditions, advantages, and disadvantages. This review primarily aims to summarize the techniques used to establish optimal animal models of corneal epithelial-stromal injury, including mechanical modeling, chemical alkali burns, post-refractive surgery infections, and genetic engineering. The intention is to provide valuable insights for studying the mechanisms underlying corneal epithelial-stromal injury and the development of corresponding therapeutic interventions.

Degradation of Levofloxacin by a green zero-valent iron-loaded carbon composite activating peroxydisulfate system: Reactivity, products and mechanism.

In this study, a green zero-valent iron-loaded carbon composite (ZVI-SCG) was synthesized using coffee grounds and FeCl3 solution through two-steps method, and the synthesized ZVI-SCG was used in the activation of peroxydisulfate (PDS) to degrade Levofloxacin (LEX). Results revealed that ZVI-SCG exhibited a great potential for LEX removal by adsorption and catalytic degradation in the ZVI-SCG/PDS system, and 99% of LEX was removed in the ZVI-SCG/PDS system within 60 min. ZVI-SCG/PDS system showed a high reactivity toward LEX degradation under realistic environmental conditions. Also, the ZVI-SCG/PDS system could effectively degrade several quinolone antibiotics including gatifloxacin, ciprofloxacin and LEX in single and simultaneous removal modes. A potential reaction mechanism of LEX degradation by ZVI-SCG/PDS system was proposed, SO4•-, HO•, O2•- and 1O2 involved in radical and non-radical pathways took part in catalytic degradation of LEX by ZVI-SCG/PDS system, but HO• might be the main reactive species for LEX degradation. The possible degradation pathway of LEX was also proposed based on the identified ten intermediate products, LEX degradation was successfully achieved through decarboxylation, opening ring and hydroxylation processes. The potential toxicity of LEX and its oxidation products decreased significantly after treatment. This study provides a promising strategy of water treatment for the antibiotics-containing wastewater.

A novel gatifloxacin-loaded intraocular lens for prophylaxis of postoperative endophthalmitis.

Postoperative endophthalmitis (POE) has been the most threatening complication after cataract surgery, which perhaps can be solved by the antibiotic-loaded intraocular lens (IOL). However, most drug-loaded IOLs demonstrate insufficient drug quantity, short release time, increased implantation-related difficulties or other noticeable drawbacks. To prevent POE and to address these deficiencies, a drug-loaded copolymer IOL, prepared from poly (urethane acrylate) prepolymer, isobornyl methacrylate (IBOMA), N-vinyl-2-pyrrolidone (NVP), Irgacure 819, RUVA-93, and gatifloxacin (GAT), was rapidly fabricated via photocuring and by using a 3D-printed mold. This composite displayed an outstanding and controllable GAT release behavior in vitro, a high light transmittance, and a moderate refractive index. Also, it demonstrated improved strain stress and elongation compared with the reference commercial acrylic IOL material. In vivo tests demonstrated satisfying released drug concentration at the early treatment stage. In vitro and in vivo studies further confirmed the remarkable bacterial inhibition and prevention of POE by the proposed IOL, which also displayed good biocompatibility. These findings suggested that the GAT-loaded IOL could be a promising implant to prevent and cure POE, also the proposed methods could inspire more designs for various medical applications.

Identification and exploration of the pyroptosis-related molecular subtypes of breast cancer by bioinformatics and machine learning.

OBJECTIVES: To classify breast cancer (BRCA) according to the expression of pyroptosis-related genes and explore their molecular characteristics. METHODS: Nonnegative matrix factorization (NMF) was used for subtype classification based on 21 pyroptosis-related genes in the TCGA database. Survival analysis and t-distributed stochastic neighbor embedding (t-SNE) analysis were conducted to assess the NMF results' performance. XGBoost, CatBoost, logistic regression, neural network, random forest, and support vector machine were utilized to perform supervised machine learning and construct prediction models. Genetic mutations, tumor mutational burden, immune infiltration, methylation, and drug sensitivity were analyzed to explore the molecular signatures of different subtypes. Lasso, RF, and Cox regression were operated to construct a prognostic model based on differentially expressed genes. RESULTS: BRCA patients were divided into two subtypes (named Cluster1 and Cluster2). Survival analysis (P = 0.02) and t-SNE analysis demonstrated that Cluster1 and Cluster2 were well classified. The XGBoost model achieved reliable predictions on both training and validation sets. Regarding molecular characteristics, Cluster1 had higher TMB, immune cell infiltration, and m6A methylation-related gene expression than Cluster2. There was also a statistically significant difference between the two subtypes concerning drug susceptibility. Finally, a 5-gene prognostic model was constructed using Lasso, RF, and Cox regression and validated in the GEO database. CONCLUSION: Our study may provide new insights from bioinformatics and machine learning for exploring pyroptosis-related subtypes and their respective molecular signatures in BRCA. In addition, our models may be helpful for the treatment and prognosis of BRCA.

Polyphenol-Assisted Exfoliation of Transition Metal Dichalcogenides into Nanosheets as Photothermal Nanocarriers for Enhanced Antibiofilm Activity.

Transition metal dichalcogenide (TMD) nanosheets have evoked enormous research enthusiasm and have shown increased potentials in the biomedical field. However, a great challenge lies in high-throughput, large-scale, and eco-friendly preparation of TMD nanosheet dispersions with high quality. Herein, we report a universal polyphenol-assisted strategy to facilely exfoliate various TMDs into monolayer or few-layer nanosheets. By optimizing the exfoliation condition of molybdenum disulfide (MoS2), the yield and concentration of as-exfoliated nanosheets are up to 60.5% and 1.21 mg/mL, respectively. This is the most efficient aqueous exfoliation method at present and is versatile for the choices of polyphenols and TMD nanomaterials. The as-exfoliated MoS2 nanosheets possess superior biomedical stability as nanocarriers to load antibiotic drugs. They show a high photothermal conversion effect and thus induce a synergetic effect of chemotherapy and photothermal therapy to harvest enhanced antibiofilm activity under near-infrared (NIR) light. All these results offer an appealing strategy toward the synthesis and application of ultrathin TMD nanosheets, with great implications for their development.

Expression, purification and characterization of human interferon-γ in Pichia pastoris.

Human interferon-γ (hIFN-γ) is a multifunctional protein known to possess immunoregulatory, antiviral and anticancer functions. In the present study, in order to explore the biological roles of hIFN-γ and its mechanisms of action, IFN-γ was cloned and expressed in Pichia pastoris (P. pastoris) under the control of alcohol oxidase promoter 1 (AOX1). The protein was secreted by two different signal peptides, the native secretion signal peptide of hIFN-γ and the Saccharomyces cerevisiae α signal peptide. Following 96 h of methanol induction, Tricine-SDS-PAGE Coomassie staining, western blot analysis and N-terminal protein sequencing revealed that the level of recombinant hIFN-γ (rhIFN-γ) secreted by the native secretion signal was barely detectable, while the α signal peptide secreted ~300 mg/l. rhIFN-γ was purified by Vivaflow 200, SP Sepharose Fast Flow and Vivaspin 2 ml, yielding >96% of a highly purified rhIFN-γ preparation, with a specific activity of 1 x 10(7)-1.4 x 10(7) IU/mg protein as determined by an antiviral assay. The results demonstrated that the experimental procedures developed are capable of producing a large quantity of active rhIFN-γ from P. pastoris.

Apoptosis of colorectal cancer UTC116 cells induced by Cantharidinate.

Effects of Cantharidinate on apoptosis of human colorectal cancer UTC-116 cells were investigated by means of 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay, H and E staining, flow cytometry, and Raman Spectra analysis. The results showed Cantharidinate to exert inhibitory action on proliferation of human colorectal cancer UTC-116 cells, inducing apoptosis, arresting cells in G1 phase, with decline of S and G2 phases. In addition, the results of Raman spectrum showed significant changes in the UTC-116 cells chemical structure with stretching after the application of Cantharidinate. Taken together, these results suggest that the treatment of human colorectal cancer with Cantharidinate may be associated with multiple molecular mechanisms for apoptosis. Furthermore, similar to fluorouracil, Cantharidinate should be considered as novel assistant drug for controlling the growth of human colorectal cancer UTC-116 cells.

catena-Poly[[[tetra-aqua-zinc(II)]-µ-4,4'-bipyridine-κN:N'] benzene-1,4-di-carboxyl-ate].

In the title compound, {[Zn(C(10)H(8)N(2))(H(2)O)(4)](C(8)H(4)O(4))}(n), the Zn(II) atoms, lying on a twofold rotation axis, are bridged by 4,4'-bipyridine ligands, resulting in a linear chain along the b axis. In the chain, the Zn(II) atom adopts a slightly distorted octa-hedral coordination geometry involving four water mol-ecules at the equatorial positions. The noncoordinated benzene-1,4-dicarboxyl-ate anion, which is also located on a twofold rotation axis, bridges adjacent chains through O-H⋯O hydrogen bonds, forming a three-dimensional supra-molecular network.

catena-Poly[diammonium [diaqua-bis(pyridine-2,4-dicarboxyl-ato-κN,O)cuprate(II)] [[diaqua-copper(II)]-µ-pyridine-2,4-dicarboxyl-ato-κN,O:O-[tetra-aqua-cadmium(II)]-µ-pyridine-2,4-dicarboxyl-ato-κO:N,O] hexa-hydrate].

The title mixed-metal complex, {(NH(4))(2)[Cu(C(7)H(3)NO(4))(2)(H(2)O)(2)][CdCu(C(7)H(3)NO(4))(2)(H(2)O)(6)]·6H(2)O}(n), contains one octa-hedrally coordinated Cd(II) center and two octa-hedrally coordinated Cu(II) centers, each lying on an inversion center. The two Cu(II) atoms are each coordinated by two O atoms and two N atoms from two 2,4-pydc (2,4-H(2)pydc = pyridine-2,4-dicarboxylic acid) ligands in the equatorial plane and two water mol-ecules at the axial sites, thus producing two crystallographically independent [Cu(2,4-pydc)(2)(H(2)O)(2)](2-) metalloligands. One metalloligand exists as a discrete anion and the other connects the Cd(H(2)O)(4) units, forming a neutral chain. O-H⋯O and N-H⋯O hydrogen bonds connects the polymeric chains, complex anions, ammonium cations and uncoordinated water mol-ecules into a three-dimensional supra-molecular network.