BACKGROUND:The micro/nanostructured gradient biomimetic surface of implant materials can simulate the structure of the extracellular environment in human bone tissue,thereby achieving perfect bone integration function.However,further research is needed on the mechanisms by which the surface microstructure of bone implant materials regulates cell function and promotes osteogenesis. OBJECTIVE:To analyze the effect of titanium sheet microstructure surface on osteogenic differentiation of MC3T3-E1 osteoblasts. METHODS:(1)At a constant voltage of 5 V or 20 V,nanotube arrays of different diameters were prepared on the surface of titanium sheets by acid etching and anodic oxidation techniques,and were recorded as group R5 and group R20,respectively.The surface morphology,roughness,and hydrophilicity of pure titanium sheet(without acid etching or anodizing treatment)were measured in group R5 and group R20.(2)MC3T3-E1 osteoblasts of logarithmic growth stage were inoculated on the surface of pure titanium sheets,R5 group and R20 group respectively.After 24 hours of osteogenic induction culture,the expression of mechanical sensitive channel protein 1 was analyzed by RT-PCR and immunofluorescence staining.Osteoblast inducible base with or without the mechanosensitive channel protein 1 activator Yada1 was added,and alkaline phosphatase staining was performed after 7 days of culture.Alizarin red staining was performed after 14 days of culture. RESULTS AND CONCLUSION:(1)The surface of pure titanium sheets was smooth under scanning electron microscope.Relatively uniform and orderly nanotube arrays with average diameters of about 30 nm and 100 nm were observed on the surface of titanium sheets of groups R5 and R20,respectively.The results of scanning electron microscope were further verified by atomic force microscopy.The surface roughness of titanium sheet of group R5 was higher than that of pure titanium(P<0.05),and the water contact angle was lower than that of pure titanium(P<0.05).The surface roughness of titanium sheet in group R20 was higher than that in group R5(P<0.05),and the water contact angle was lower than that in group R5(P<0.05).(2)RT-PCR and immunofluorescence staining showed that the expression of mechanosensitive channel protein 1 in group R5 was higher than that in pure titanium group(P<0.05),and the expression of mechanosensitive channel protein 1 in group R20 was higher than that in group R5(P<0.05).Under the osteogenic induction,compared with the condition without Yada1,there were no significant changes in the activity of alkaline phosphatase and the deposition of calcified nodules in pure titanium group after Yada1 addition,while the activity of alkaline phosphatase and the deposition of calcified nodules in groups R5 and R20 after Yada1 addition were significantly increased(P<0.05).With or without Yada1,the alkaline phosphatase activity and calcified nodule deposition in group R5 were higher than those in pure titanium group(P<0.05),and the alkaline phosphatase activity and calcified nodule deposition in group R20 were higher than those in group R5(P<0.05).(3)The results show that the surface microstructure of titanium sheet can promote the osteogenic differentiation of osteoblast MC3T3-E1 by activating mechanosensitive channel protein 1.

Aim To investigate the dynamic changes of neuronal cells at different time points following acute cerebral ischemia-reperfusion injury by establishing a model of brain ischemia-reperfusion injury.Methods Thirty male Sprague-Dawley(SD)rats were ran-domly divided into six groups:sham group and cere-bral ischemia-reperfusion injury(IR)groups at differ-ent time points.Focal cerebral ischemia-reperfusion injury model was established using the middle cerebral artery occlusion(MCAO)technique.The Longa sco-ring method was used to assess neurobehavioral scores in rats.After successful model preparation,routine paraffin sections were made,and TUNEL staining and immunohistochemistry staining with NeuN antibody were performed to observe cell apoptosis and neuronal cell survival,respectively.Immunohistochemistry stai-ning was also performed to investigate the changes in glial fibrillary acidic protein(GFAP)as a marker for astrocytes,ionized calcium-binding adapter molecule 1(IBA-1)as a marker for microglia,and CD31 as a marker for endothelial cells at different time points.Results No significant changes were observed in neu-ronal cells of the sham group at different time points.In the cerebral ischemia-reperfusion injury groups,cell apoptosis was activated at IR3h and increased in quan-tity with morphological damage as time progressed.Ne-uN+neurons showed signs of ischemic injury after IR3h,with abnormal cell morphology.From 12 h,Ne-uN+neurons decreased in a time-dependent manner and reached their peak severity at 24 h.GFAP+astro-cytes decreased significantly after IR3h,while poorly labeled GFAP+astrocytes increased at IR 6 h and al-most disappeared in the infarcted area at 24 h and 48 h.The number of IBA-1+microglia-positive cells de-creased at IR3h,and their volume increased at IR6h.Microglial cell death was observed in the infarcted area at IR12h.CD31+endothelial cells around the infarc-ted cortex and striatum increased significantly after IR3h and persisted until 48 h.Conclusions After cerebral ischemia-reperfusion injury,the number of ap-optotic cells increases with the prolongation of time,and NeuN+neurons exhibit the most severe damage at 24 h.GFAP+astrocytes and microglial cells gradually die over time.The number of CD31+endothelial cells increases significantly around the infarcted cortex and striatum after 3 h of reperfusion and persists until 48 h.

A prokaryotic expression vector for the mutant diphtheria toxin CRM197 was constructed and expressed in Esch-erichia coli cells.Anti-CRM197 antibody concentrations were detected in serum samples of healthy volunteers.The crm 197 gene was codon-optimized in E.coli and cloned into the plasmid pET28a(+)under optimized expression conditions.CRM197 was purified using Ni-NTA spin columns and ion exchange chromatography,and confirmed by western blot analysis.The puri-fied CRM197 was used to detect specific anti-CRM197 antibody levels in serum samples of different age groups.The results showed that soluble codon-optimized CRM197 was successfully expressed under optimized expression conditions.The purity of CRM197 was more than 95％,as determined with Ni-NTA spin columns and ion exchange chromatography,consistent with the single specific bands obtained by western blot analysis and detection of serum levels of the anti-CRM197 antibody.Collec-tively,these results confirmed that the proposed expression strategy achieved high-yield production of soluble CRM197,al-though high levels in human serum may affect evaluation of immune interactions with glycan-CRM197 conjugates for applica-tion as a diagnostic antigen.The diphtheria mutant toxin CRM197 is used in many conjugate vaccines.The synthetic crm 197 gene with codon optimization in pET28a was transformed into E.coli Origami B(DE3)cells.CRM197 was induced by isopro-pyl β-d-1-thiogalactopyranoside and high level accumulation of soluble CRM197 was purified using Ni-NTA spin columns and ion exchange chromatography.The purity of the final prepara-tion reached 95％.CRM197 was used to detect the concentra-tions of the anti-CRM197 antibody in serum samples of healthy volunteers of different ages.The proposed expression strategy yielded high production of CRM197,which could interfere with evaluations of induced immune interactions by glycan-CRM197 conjugates and prohibit application as a diagnostic antigen.

Parkinson's disease is a neurodegenerative disease associated with abnormal copper metabolism in the brain,which leads to misfolding and aggregation of α-synuclein-copper complexes,which is an important pathological sign of Parkinson's disease.Copper metabolism,i.e.,cellular metabolic processes involving copper ions,is closely related to the pathogenesis of α-synuclein aggregation,dopamine metabolism,mitochondrial dysfunction,oxidative stress,and ferroptosis in Parkinson's disease.In this review,we summarize the molecular metabolic mechanism of copper toxicity by studying the pathological role of copper metabolism in Parkinson's disease,to support our further understanding of the mechanism of action and drug development.

African swine fever(ASF)is a highly contagious and pathogenic disease affecting both domestic and wild pigs,which is caused by African swine fever virus(ASFV).In European epidem-ics,low-virulence strains of ASFV,which do not have hemadsorbing properties,have been identi-fied.Following the identification of highly virulent genotype Ⅱ ASFV strains in China in 2018,subsequently,low-virulence strains of genotype Ⅱ and genotype Ⅰ emerged.Recombination be-tween genotypes Ⅰ and Ⅱ has also led to the occurrence of high-virulence strains.This indicates a complex and diverse genetic evolution of ASFV during the epidemiological transmission,which po-ses significant challenges for vaccine development and disease surveillance.Here,we provide an o-verview of the novel epidemiological characteristics of ASFV,with a focus on genetic variations and pathogenic differences during the outbreaks of ASF.We also explore how ASFV genetic varia-tions impact immune escape and pathogenicity of the virus,and the challenges they pose for vac-cine development,disease diagnosis,and surveillance.The aim of this review is to enhance our un-derstanding of the genetic evolution and mutation mechanisms of ASFV,providing a theoretical basis for the development of vaccines and research on diagnostic technologies.

The application of the smart bed in some hospital from October 2018 to January 2023 was introduced,and the patients using the smart bed were compared with those with the ordinary bed in terms of inpatient department,length of stay,fall/bed fall prediction score,occurrence of adverse events and patient satisfaction.The application effect of the smart bed was summarized.The problems during the application of the smart bed were analyzed,and some suggestions were put forward accordingly.References were provided for the improvement of the smart bed.[Chinese Medical Equipment Journal,2024,45(7):77-80]

Objective To investigate the current status of off-label drug use(OLDU)management in tertiary hospitals of Guizhou province and to provide baseline evidence for developing a unified administration regulation for OLDU in Guizhou province.Methods In line with the relevant policies and regulations,a questionnaire including basic information about the person filling out the form,basic information about the hospitals,and information about OLDU was developed.The questionnaire was sent to 84 tertiary hospitals in Guizhou province through the Wenjuanxing.Results A total of 84 questionnaires were distributed and recovered,with a response rate of 100.00%.Of the 84 hospitals,77 had OLDU,of which 68(88.31%)had established a management system for OLDU.Among the 77 hospitals with OLDU,65(84.42%),42(54.55%),58(75.32%),36(46.75%),15(19.48%),and 21(27.27%)hospitals respectively,required approval from the Committee on Drug Administration and Pharmacotherapy before OLDU,restricted the qualifications of doctors prescribing OLDU,required informed consent from patients or their families before OLDU,recorded the matters and reasons in the medical records of patients treated with OLDU,followed up patients in their files and evaluated the reasonableness of the OLDU,and carried out special reviews for OLDU.Only 30(38.96%)hospitals have set up a catalogue of OLDUs,and 58(75.32%)hospitals have urgent needs to set up a unified provincial catalogue of OLDUs.Conclusion The pharmacy administration level of OLDU in tertiary hospitals of Guizhou province is relatively low,so there is an urgent need to establish a unified OLDU management system and medication catalog.

Objective To observe the ultrasonic manifestations and possible etiology of fetal tricuspid regurgitation(TR).Methods Totally 717 fetuses diagnosed with TR by prenatal ultrasound were retrospectively enrolled,and the prenatal ultrasonic findings were observed.Based on postpartum follow-up data,the fetuses were divided into physiological TR group(n=468)and pathological TR group(n=249),and those in the latter were further divided into right heart preload increase subgroup(n=76),right heart afterload increase subgroup(n=127)and tricuspid valve structure abnormality subgroup(n=46)according to the possible etiology,and the ultrasonic manifestations were comparatively analyzed.Results In physiological TR group,mild and moderate TR was found in 441(441/468,94.23％)and 27 fetuses(27/468,5.77％),respectively,while no severe TR was noticed.In pathological TR group,significant difference of TR degrees was found among 3 subgroups(x2=37.244,P＜0.001).Mild TR was more common in right heart preload increase subgroup,while moderate and severe TR were more common in the other 2 subgroups.In right heart preload increase subgroup,fetuses with persistent left superior vena cava were more likely to develop mild TR,while those with intact interventricular septum and pulmonary artery occlusion were more likely to develop severe TR in right heart afterload increase subgroup(both P＜0.05).No significant difference of TR degree was found among fetuses with different possible etiology in right heart preload increase subgroup nor right heart afterload increase subgroup(both P＞0.05).In tricuspid valve structure abnormality subgroup,significant differences of TR degrees were found among fetuses with different possible etiologies(P＜0.05),and fetuses with underdeveloped tricuspid valve were more prone to severe reflux(P＜0.05).There were significant differences of reflux velocity of moderate and severe TR among 3 subgroups(F=6.945,P=0.002).Conclusion Fetal TR was mostly physiological.The possible etiologies of pathological TR were variable,including pulmonary valve stenosis,persistent left superior vena cava and tricuspid valve hypoplasia,with different prenatal ultrasonic manifestations.

Aim To investigate the dynamic time-course changes in neuronal cytoskeleton after acute ischemia and reperfusion in rats. Methods Reperfusion was performedin rats by blocking the middle cerebralarteryfor 90 min, then therats wereobserved and collected at different time points. The brain damage wasobserved by Nissl staining,and neurobehavioural function was evaluated with neurological deficit score and forelimb placement test. The cellular changes in the alternations of cytoskeletal elements including microtubule associated protein 2 (MAP2) and neurofilament heavy chain (NF-H) were observed by immunohistochemistry staining and Western blot. Impaired axons, dendrites and cytoskeletal alternations were detected by electron microscope. Results Brain damage and neurobehavioural function were gradually aggravated with the prolongation of reperfusion. Brain damage appeared earlier and more severe in striatum than in cortex. Moreover, decreased MAP2-related and increased NF-H-related immunoreactive intensities were found in the ischemic areas. Impaired cytoskeletal arrangement and reduced dense were indicated. Damaged cytoskeletal components such as microtubules and neurofilament arrangement, decreased axonal filament density, and swelled dendrites were observed after cerebral ischemia reperfusion by ultrastructural observations. Conclusions Different brain regions have diverse tolerance to ischemia-reperfusion injury. Major elements of neuronal cytoskeleton show dynamic responses to ischemia and reperfusion, which may further contribute to brain damage and neurological impairment following MCAO and reperfusion.

Recent clinical studies have shown that mutation of phosphatase and tensin homolog deleted on chromosome 10 (PTEN) gene in cancer cells may be associated with immunosuppressive tumor microenvironment (TME) and poor response to immune checkpoint blockade (ICB) therapy. Therefore, efficiently restoring PTEN gene expression in cancer cells is critical to improving the responding rate to ICB therapy. Here, we screened an adeno-associated virus (AAV) capsid for efficient PTEN gene delivery into B16F10 tumor cells. We demonstrated that intratumorally injected AAV6-PTEN successfully restored the tumor cell PTEN gene expression and effectively inhibited tumor progression by inducing tumor cell immunogenic cell death (ICD) and increasing immune cell infiltration. Moreover, we developed an anti-PD-1 loaded phospholipid-based phase separation gel (PPSG), which formed an in situ depot and sustainably release anti-PD-1 drugs within 42 days in vivo. In order to effectively inhibit the recurrence of melanoma, we further applied a triple therapy based on AAV6-PTEN, PPSG^@anti-PD-1 and CpG, and showed that this triple therapy strategy enhanced the synergistic antitumor immune effect and also induced robust immune memory, which completely rejected tumor recurrence. We anticipate that this triple therapy could be used as a new tumor combination therapy with stronger immune activation capacity and tumor inhibition efficacy.