Immobilized enzyme-based enzyme electrode biosensors, characterized by high sensitivity and efficiency, strong specificity, and compact size, demonstrate broad application prospects in life science research, disease diagnosis and monitoring, etc. Immobilization of enzyme is a critical step in determining the performance (stability, sensitivity, and reproducibility) of the biosensors. Random immobilization (physical adsorption, covalent cross-linking, etc.) can easily bring about problems, such as decreased enzyme activity and relatively unstable immobilization. Whereas, directional immobilization utilizing amino acid residue mutation, affinity peptide fusion, or nucleotide-specific binding to restrict the orientation of the enzymes provides new possibilities to solve the problems caused by random immobilization. In this paper, the principles, advantages and disadvantages and the application progress of enzyme electrode biosensors of different directional immobilization strategies for enzyme molecular sensing elements by specific amino acids (lysine, histidine, cysteine, unnatural amino acid) with functional groups introduced based on site-specific mutation, affinity peptides (gold binding peptides, carbon binding peptides, carbohydrate binding domains) fused through genetic engineering, and specific binding between nucleotides and target enzymes (proteins) were reviewed, and the application fields, advantages and limitations of various immobilized enzyme interface characterization techniques were discussed, hoping to provide theoretical and technical guidance for the creation of high-performance enzyme sensing elements and the manufacture of enzyme electrode sensors.

BACKGROUND:Fibromyalgia syndrome,as a common rheumatic disease,is related to central sensitization and immune abnormalities.However,the specific mechanism has not been elucidated,and there is a lack of specific diagnostic markers.Exploring the possible pathogenesis of this disease has important clinical significance. OBJECTIVE:To screen the potential diagnostic marker genes of fibromyalgia syndrome and analyze the possible immune infiltration characteristics based on bioinformatics methods,such as weighted gene co-expression network analysis(WGCNA),and machine learning. METHODS:Gene expression profiles in peripheral serum of fibromyalgia syndrome patients and healthy controls were obtained from the gene expression omnibus(GEO)database.The differentially co-expressed genes were screened in the expression profile by differential analysis and WGCNA analysis.Least absolute shrinkage and selection operator(LASSO)and support vector machine-recursive feature elimination(SVM-RFE)machine learning algorithm were further used to identify hub biomarkers,and draw receiver operating characteristic curve(ROC)to evaluate the accuracy of diagnosing fibromyalgia syndrome.Finally,single sample gene set enrichment analysis(ssGSEA)and gene set enrichment analysis(GSEA)were used to evaluate the immune cell infiltration and pathway enrichment in patients with fibromyalgia syndrome. RESULTS AND CONCLUSION:Eight down-regulated differentially expressed genes(DEGs)were obtained after differential analysis of the GSE67311 dataset according to the conditions of log2|(FC)|>0 and P<0.05.After WGCNA analysis,497 genes were included in the module(MEdarkviolet)with the highest positive correlation(r=0.22,P=0.04),and 19 genes were included in the module(MEsalmon2)with the highest negative correlation(r=-0.41,P=6×10-5).After intersecting DEGs and the module genes of WGCNA,seven genes were obtained.Four genes were screened out by LASSO regression algorithm and five genes were screened out by SVM-RFE machine learning algorithm.After the intersection of the two,three core genes were identified,which were germinal center associated signaling and motility like,integrin beta-8,and carboxypeptidase A3.The areas under the ROC curve of the three core genes were 0.744,0.739,and 0.734,respectively,indicating that they have good diagnostic value and can be used as biomarkers for fibromyalgia syndrome.The results of immune infiltration analysis showed that memory B cells,CD56 bright NK cells,and mast cells were significantly down-regulated in patients with fibromyalgia syndrome compared with the control group(P<0.05),and were significantly positively correlated with the above three biomarkers(P<0.05).The enrichment analysis suggested that there were nine fibromyalgia syndrome enrichment pathways,mainly related to olfactory transduction pathway,neuroactive ligand-receptor interaction,and infection pathway.The above results showed that the occurrence and development of fibromyalgia syndrome are related to the involvement of multiple genes,abnormal immune regulation,and multiple pathways imbalance.However,the interactions between these genes and immune cells,as well as their relationships with various pathways need to be further investigated.

Non-clinical reproductive toxicity studies typically employ mammals like rats, rabbits, and cynomolgus monkeys, with animal pregnancy being a key challenge in such testing. This article focuses on the difficulties encountered in the animal pregnancy process and potential countermeasures. Rats can be used for fertility and early embryonic development toxicity studies (Segment Ⅰ), embryo-fetal development toxicity studies (Segment Ⅱ), and perinatal toxicity studies (Segment Ⅲ). The estrous cycle of female rats can be determined by vaginal smear, and mating behavior is confirmed through copulatory plug checks the following day after pairing one female with one male in the same cage. Rabbits are commonly used in embryo-fetal development toxicity studies (Segment Ⅱ). Mating behavior between male rabbits and estrous females is observed to determine the time of conception. However, challenges such as atypical estrus of female rabbits, large variations in estrus between batches, and mating failure often occur in reproductive toxicity testing, which may be addressed through prolonged light exposure, increased protein supplementation, optimized mating strategies, and environmental modifications like female and male rabbits are raised adjacent to each other. Non-human primates (NHPs) are typically employed in perinatal toxicity studies (Segment Ⅲ), where one of the key challenges lies in accurately determining sexual maturity in males - a critical factor for reproductive toxicity testing, which can be assessed through comprehensive evaluation of age, body weight, and testicular volume. Generally, male macaques are considered sexually mature when they meet the following criteria: age >4.5 years, body weight >4.5 kg, single testis volume >10 mL, and combined testicular volume >20 mL. For pregnancy confirmation, ultrasound examination demonstrating visible gestational sacs is required, though this necessitates experienced veterinary clinicians to establish standardized ultrasound examination protocols. In conclusion, reproductive toxicity studies should employ species-appropriate detection methods and evaluation criteria based on anatomical characteristics of the reproductive system to ensure successful mating and proper study execution.

AIM:To evaluate the efficacy of corneal stromal lenses combined with 0.1% cyclosporine A eye drops in patients with Mooren's ulcer and its effect on ocular surface inflammatory factors.METHODS:In this prospective randomized controlled trial, 200 patients(272 eyes)with Mooren's ulcer were enrolled from January 2022 to January 2024. Patients were randomly assigned to receive either corneal stromal lenses alone(control group: 100 patients, 136 eyes)or combined with 0.1% cyclosporine A eye drops(observation group: 100 patients, 136 eyes). All patients were followed up for 3 mo. Clinical efficacy, visual acuity improvement, recovery time, pain score, complications, and tear levels of interleukin(IL)-1β, IL-6, and tumor necrosis factor-α(TNF-α)were compared between the two groups.RESULTS:A total of 196 patients(268 eyes)completed follow-up, with 2 cases(2 eyes)lost to follow-up in each group and a lost to follow-up rate of 2.0%. The observation group showed a higher total effective rate(95.5% vs 83.6%, P<0.05). Postoperative best corrected visual acuity(LogMAR)of the observation group was significantly better than that of the control group(0.42±0.15 vs 0.65±0.18, P<0.001). Epithelial(5.24±1.15 vs 7.86±1.43 d)and stromal recovery(12.35±2.46 vs 16.72±3.15 d)were faster in the observation group(both P<0.001). Pain scores and complication rates of the observation group were lower than those of the control group(both P<0.001). Both groups showed reduced tear IL-1β, IL-6, and TNF-α levels postoperatively, with greater reductions in the observation group(P<0.001).CONCLUSION: Corneal stromal lenses combined with 0.1% cyclosporine A eye drops provide superior outcomes for Mooren's ulcer by enhancing visual recovery, accelerating corneal healing, reducing pain, and lowering complications, potentially through inhibition of ocular surface inflammatory factors.

The main protease (M^pro) of SARS-CoV-2 is an attractive target in anti-COVID-19 therapy for its high conservation and major role in the virus life cycle. The covalent M^pro inhibitor nirmatrelvir (in combination with ritonavir, a pharmacokinetic enhancer) and the non-covalent inhibitor ensitrelvir have shown efficacy in clinical trials and have been approved for therapeutic use. Effective antiviral drugs are needed to fight the pandemic, while non-covalent M^pro inhibitors could be promising alternatives due to their high selectivity and favorable druggability. Numerous non-covalent M^pro inhibitors with desirable properties have been developed based on available crystal structures of M^pro. In this article, we describe medicinal chemistry strategies applied for the discovery and optimization of non-covalent M^pro inhibitors, followed by a general overview and critical analysis of the available information. Prospective viewpoints and insights into current strategies for the development of non-covalent M^pro inhibitors are also discussed.

Nucleic acid-based molecular diagnostic methods are considered the gold standard for detecting infectious pathogens.However,when applied to portable or on-site rapid diagnostics,they still face various limitations and challenges,such as poor specificity,cumbersome operation,and portability difficulties.The CRISPR(Clustered regularly interspaced short palindromic repeats)/CRISPR-associated protein(Cas)-fluorescence detection method holds the potential to significantly enhance the specificity and signal-to-noise ratio of nucleic acid detection.In this study,we developed a portable grayscale reader detection system based on loop-mediated isothermal amplification(LAMP)-CRISPR/Cas.On one hand,in the presence of CRISPR RNA(crRNA),the CRISPR/Cas12a system was employed to achieve precise fluorescent detection of self-designed LAMP amplification reactions for influenza A and influenza B viruses.This further validated the high selectivity and versatility of the CRISPR/Cas system.On the other hand,the accompanying independently developed portable grayscale reader allowed for low-cost collection of fluorescence signals and high-reliability visual interpretation.At the end of the detection process,it directly provided positive or negative results.Practical sample analyses using this detection system have verified its reliability and utility,demonstrating that this system can achieve highly sensitive and highly specific portable analysis of influenza viruses.

Objective To explore the application effect of enteral nutrition-related diarrhea in postoperative esophageal cancer patients.Methods Based on literature search and expert meeting,a management process for enteral nutrition-associated diarrhea in postoperative esophageal cancer patients was constructed.A convenience sampling method was used to select a total of 68 patients with enteral nutrition-related diarrhea after esophageal cancer surgery admitted to the thoracic surgery department of a tertiary A cancer hospital in Jiangsu Province.Among them,patients admitted from January 2022 to December 2022 were set as an experimental group.The experimental group was implemented the management process for enteral nutrition-associated diarrhea in postoperative esophageal cancer patients.Those admitted from January 2021 to December 2021 were set as a control group with routine nursing.Then,the time of stopping diarrhea,the King's of Stool Chart(KSC-Tr)diarrhea score,and abnormal incidence of nutrition-related indexes,electrolytes abnormalities(low sodium,low potassium,and low calcium)were compared between 2 groups.Results The time of stopping diarrhea,KSC diarrhea score after 3 days of intervention and the time to achieve target feeding volume of the experimental group were lower than those in the control group,and the difference was statistically significant(P＜0.05).There were no significant differences in hemoglobin,albumin,prealbumin after 3 days of intervention,the incidence of electrolyte abnormalities(low sodium,low potassium,and low calcium)after 3 days of intervention,and the BMI index after 7 days of intervention between 2 groups(P＞0.05).Conclusion The management process for enteral nutrition-associated diarrhea in postoperative esophageal cancer patients can reduce the time of diarrhea,improve the severity of diarrhea,and shorten the time to achieve the target feeding,but has no significant change in the incidence of electrolyte abnormalities.

Orodispersible films (oral dispersible films), a novel form of oral solid dosage forms, are widely used for patients with dysphagia and those with uncontrollable autonomic behavior. In this study, suvorexant orodispersible film was prepared by hot melt extrusion technology, and the disintegration time, mechanical properties, in vitro dissolution and pharmacokinetics were evaluated, compared with other orodispersible films and commercially available tablets Belsomra. All experiments were approved by the Committee on the Management and Use of Laboratory Animals of Academy of Military Medical Sciences (IACUC-DWZX-2024-504). The results showed that the dissolution rate of suvorexant orodispersible film was faster and the mechanical strength was better than that of other commercially available orodispersible film, which could meet the needs of storage and transportation. Differential scanning calorimetry and X-ray diffraction results showed that suvorexant was dispersed within the orodispersible film in an amorphous state. The in vitro dissolution of the film was observed to be four times faster than that of the commercial tablets, achieving complete dissolution within five minutes. Pharmacokinetic evaluations in Beagle dogs revealed that the self-formulated orodispersible film exhibited no significant differences in the area under the blood concentration-time curve when compared with Belsomra. However, the film showed a faster onset of action, with a peak time that was twice as rapid, and a maximum blood concentration that was twice as high as that of Belsomra. Leveraging hot melt extrusion technology, the suvorexant orodispersible film offers a straightforward, continuous production process with consistent quality. It serves as an excellent platform for the development of solvent-free film preparations tailored for patients with special needs.

The rheological properties of drug and carrier materials have a wide range of guiding significance for the formulation and process development of solid dispersions. In this study, the rheological properties of materials with different drug carrier ratios were systematically studied with suvorexant as the model drug and copovidone as the carrier material, which provided a sufficient basis for determining the formulation and process of solid dispersions. The optimal suvorexant-copovidone ratio obtained by oscillating temperature scanning was 1∶4. If the ratio is greater than 1∶ 4, the glass transformation temperature of the material will increase significantly, and the solubilization effect of the solid dispersion will show a downward trend. The results of oscillation temperature scanning and oscillation temperature sweep can show that when the extrusion temperature is greater than 150 ℃, the viscosity of the material is less than 10 000 Pa·s, and the melt can be extruded smoothly, and the best extrusion temperature of 160-180 ℃ can be obtained by combining the dissolution results. Finally, the dissolution of suvorexant tablets guided by rheological property studies in multiple media is similar to that of the commercially available tablets Belsomra. Therefore, rheological studies can screen and optimize the formulation and process of suvorexant solid dispersions at the mechanism level, which is of great significance to improve the success rate of R&D and shorten the R&D cycle of solid dispersions prepared by hot melt extrusion.

Cryoablation therapy with explicit anti-tumor mechanisms and histopathological manifestations has a long history.A large number of clinical practice has shown that cryoablation therapy is safe and effective,making it an ideal tumor treatment method in theory.Previously,its efficacy and clinical application were constrained by the limitations of refrigerants and refrigeration equipment.With the development of the new generation of cryoablation equipment represented by argon helium knives,significant progress has been made in refrigeration efficien-cy,ablation range,and precise temperature measurement,greatly promoting the progression of tumor cryoablation technology.This consensus systematically summarizes the mechanism of cryoablation technology,indications for oral mucosal melanoma(OMM)cryotherapy,clinical treatment process,adverse reactions and management,cryotherapy combination therapy,etc.,aiming to provide reference for carrying out the standardized cryoablation therapy of OMM.