Humans ; Aged ; Lung Diseases ; Pneumonia/drug therapy* ; Adrenal Cortex Hormones/therapeutic use* ; Pulmonary Disease, Chronic Obstructive/drug therapy* ; Administration, Inhalation ; Community-Acquired Infections/drug therapy*

BACKGROUND:Polylactic acid has good biocompatibility and biodegradability,and has become a new orthopedic fixation material.However,the lack of cell recognition signal of this material is not conducive to cell adhesion and osteogenic differentiation,which limits its application in biomaterials. OBJECTIVE:3D-printed polylactic acid-nano-hydroxyapatite(nHA)/chitosan(CS)scaffold to evaluate its drug sustained-release and biological properties. METHODS:The porous polylactic acid scaffold(recorded as PLA scaffold)with interporous pores was printed by fused deposition modeling technique,and the scaffold was soaked in dopamine solution to prepare polylactic acid-dopamine scaffold(recorded as PLA-DA scaffold).Nano-hydroxyapatite was immersed in chitosan solution,and then the PLA-DA scaffold was immersed in it to prepare polylactic acid-nano-hydroxyapatite/chitosan scaffold(recorded as PLA-nHA/CS scaffold).The micro-morphology,porosity,water contact angle,and compressive strength of the three scaffolds were characterized.PLA-nHA/CS scaffold loaded with doxycycline(recorded as PLA-nHA/CS-DOX scaffold)was prepared by freeze-drying method,and its drug release was characterized.PLA,PLA-DA,PLA-nHA/CS,and PLA-nHA/CS-DOX scaffolds were co-cultured with MC3T3-E1 cells,separately,to detect cell proliferation and osteogenic differentiation.Staphylococcus aureus suspensions of different concentrations were co-cultured with four groups of scaffolds.The antibacterial performance of scaffolds was detected by inhibition zone test. RESULTS AND CONCLUSION:(1)Under scanning electron microscopy,the surfaces of PLA and PLA-DA scaffolders were dense and smooth,and nHA particles were observed on PLA-nHA/CS scaffolders.The porosity of PLA,PLA-DA and PLA-nHA/CS scaffolds decreased gradually,and the compressive strength increased gradually.The elastic modulus of PLA-nHA/CS scaffolds met the requirements of cancelous bone.The water contact angle of PLA-DA and PLA-nHA/CS brackets was smaller than that of PLA scaffolds.The PLA-nHA/CS scaffold sustainably released drugs in vitro for 8 days.(2)CCK-8 assay showed that the proliferation of MC3T3-E1 cells was not significantly affected by the four groups of scaffolds.The activity of alkaline phosphatase in PLA-DA group,PLA-nHA/CS group,and PLA-nHA/CS-DOX group was higher than that in PLA group.Alizarin red staining showed that compared with PLA group,the cells in PLA-nHA/CS group and PLA-nHA/CS-DOX group showed higher mineralized water level.(3)Inhibition zone test exhibited that PLA and PLA-DA scaffolds had no antibacterial properties.PLA-nHA/CS scaffolds had certain antibacterial properties.PLA-nHA/CS-DOX scaffolds had super antibacterial properties.(4)The results showed that the PLA-nHA/CS-DOX scaffold had good drug release performance,cell compatibility,osteogenic properties,and antibacterial properties.

Objective To investigate the potential of immune-inflammatory markers and the characteristics of magnetically controlled capsule endoscopy in distinguishing gastric adenocarcinoma from precancerous lesions,as well as to develop and validate a risk prediction model.Methods Retrospective analysis was conducted on medical records of 578 patients who underwent magnetic controlled capsule endoscopy at our hospital between January 2021 and December 2023.Following the principle of Pareto's law(80/20 rule),they were randomly divided into a training set(462 cases)and a validation set(116 cases).Magnetic controlled capsule endoscopy and blood cell tests were performed,with pathological diagnosis results serving as the"gold standard",to classify patients into groups of gastric adenocarcinoma and precancerous lesions.The magnetic controlled capsule endoscopic features,neutrophil-lymphocyte ratio(NLR),platelet-lymphocyte ratio(PLR)in patients with gastric adenocarcinoma and precancerous lesions were compared to develop and validate a risk diagnostic model for gastric adenocarcinoma.Results Among the 462 patients who underwent magnetic controlled capsule endoscopy,gastric adenocarcinoma was diagnosed in 76 cases through pathological examination,accounting for 16.45%(76/462),while precancerous lesions were observed in 386 cases,accounting for 83.55%(386/462).In the validation set of 116 patients who underwent gastric endoscopy,there were 22 cases of gastric adenocarcinoma,representing an incidence rate of 18.97%(22/116),and a total of 94 cases with precancerous lesions,accounting for an incidence rate of 81.03%(94/116).No statistically significant differences(P＞0.05)were found between the two groups regarding lesion size,border appearance,mucus presence or lesion morphology.However,compared to the precancerous lesion group,the proportion of whitish coloration as well as irregular surface microstructure and grid-like microvessels was significantly higher in the gastric adenocarcinoma group(P＜0.05).Moreover,both NLR and PLR values were significantly higher in the gastric adenocarcinoma group compared to those in the precancerous lesion group(P＜0.05).Irregular surface microstructure(OR=2.213,95%CI:1.288～3.801),irregular grid-like microvessels(OR=2.489,95%CI:1.458～4.249),NLR(OR=2.369,95%CI:1.389～4.046),and PLR(OR=3.016,95%CI:1.767～5.148)were identified as risk factors for gastric adenocarcinoma(P＜0.05).The sensitivity of the risk model for diagnosing gastric adenocarci-noma in the training set was 0.800(95%CI:0.716～0.891),with a specificity of 0.783(95%CI:0.694～0.851)and an area under the curve of 0.858(95%CI:0.787～0.931).In the validation set,the sensitivity for diagnosing gastric adenocarcinoma was 0.861(95%CI:0.771～0.945),with a specificity of 0.769(95%CI:0.683～0.841)and an area under the curve of 0.844(95%CI:0.765～0.923).Conclusion The surface microstructure,microvas-cular morphology,NLR,and PLR of gastric lesions are correlated with the occurrence of gastric adenocarcinoma.Developing a risk diagnostic model facilitates early identification and diagnosis of gastric adenocarcinoma.

Objective:To develop and evaluate the efficacy and safety of a three-dimensional (3D) digestive endoscope for gastric endoscopic submucosal dissection (ESD) through animal experiments.Methods:Two Dutch pigs were utilized from the Zhengzhou University Animal Experiment Center for the study. ESD procedures were performed by two senior endoscopists, one using 3D glasses and the other utilizing a 3D high-definition head display. The success of ESD was assessed based on predefined criteria, including completion of surgical steps, complete detachment of the presumptive lesion, and effective bleeding control during and after the surgery. The number of successful procedures and incidences of perforation were recorded. The stereoscopic experience of the endoscopists, including both the primary endoscopist and the assistant, was also evaluated. Furthermore, the assessment encompassed any reported symptoms of eye discomfort, such as eye fatigue, ocular pain, and blurred vision. Additionally, the confidence level of the endoscopists in the mechanical aspects of the operation, as well as encountered issues during the endoscopic procedures, were documented.Results:Two ESD were successful and no perforation occurred. Feedback from endoscopists suggested that 3D digestive endoscopy offered clear images with enhanced three-dimensionality during surgery, clear sense of distance and layering, allowing for a precise judgment of bleeding points, which surpassed 2D capabilities. No eye discomfort was experienced by endoscopists or assistants during or after the procedures. While endoscopists exhibited high confidence in 3D digestive endoscopy, they noted issues with image blurring when the camera was positioned less than 10 mm from the gastrointestinal tract wall.Conclusion:Preliminary results show that 3D digestive endoscopes can provide excellent stereo imaging, improved positioning accuracy, and safety during live animal stomach ESD procedures, without significantly increasing endoscopists' eye discomfort. Nevertheless, efforts are needed to address image blurring concerns when the camera is close to the gastrointestinal tract wall.

OBJECTIVE: To explore the role of endoplasmic reticulum ryanodine receptor 1 (RyR1) expression and phosphorylation in sepsis- induced diaphragm dysfunction. METHODS: Thirty SPF male SD rats were randomized equally into 5 groups, including a sham-operated group, 3 sepsis model groups observed at 6, 12, or 24 h following cecal ligation and perforation (CLP; CLP-6h, CLP-12h, and CLP-24h groups, respectively), and a CLP-24h group with a single intraperitoneal injection of KN- 93 immediately after the operation (CLP-24h+KN-93 group). At the indicated time points, diaphragm samples were collected for measurement of compound muscle action potential (CMAP), fatigue index of the isolated diaphragm and fitted frequencycontraction curves. The protein expression levels of CaMK Ⅱ, RyR1 and P-RyR1 in the diaphragm were detected using Western blotting. RESULTS: In the rat models of sepsis, the amplitude of diaphragm CMAP decreased and its duration increased with time following CLP, and the changes were the most obvious at 24 h and significantly attenuated by KN-93 treatment (P < 0.05). The diaphragm fatigue index increased progressively following CLP (P < 0.05) irrespective of KN- 93 treatment (P>0.05). The frequency-contraction curve of the diaphragm muscle decreased progressively following CLP, and was significantly lower in CLP-24 h group than in CLP-24 h+KN-93 group (P < 0.05). Compared with that in the sham-operated group, RyR1 expression level in the diaphragm was significantly lowered at 24 h (P < 0.05) but not at 6 or 12 following CLP, irrespective of KN-93 treatment; The expression level of P-RyR1 increased gradually with time after CLP, and was significantly lowered by KN-93 treatment at 24 h following CLP (P < 0.05). The expression level of CaMKⅡ increased significantly at 24 h following CLP, and was obviously lowered by KN-93 treatment (P < 0.05). CONCLUSION Sepsis causes diaphragmatic dysfunction by enhancing CaMK Ⅱ expression and RyR1 receptor phosphorylation in the endoplasmic reticulum of the diaphragm.
Rats ; Male ; Animals ; Diaphragm/metabolism* ; Ryanodine Receptor Calcium Release Channel/metabolism* ; Rats, Sprague-Dawley ; Phosphorylation ; Muscle Contraction/physiology* ; Endoplasmic Reticulum ; Sepsis/metabolism*

Objective:To evaluate the relationship between intestinal microbiota heterogeneity and acquired myasthenia in septic mice.Methods:Eighty SPF healthy male C57BL/6 mice, weighing 18-20 g, aged 6-8 weeks, were included. Forty mice were selected to prepare a sepsis model by intraperitoneal injection of lipopolysaccharide (LPS) 10 mg/kg. Sepsis-sensitive mice (state of dying or even death within 24 h after developing the model) and sepsis-resistant mice (survival for 7 days and recovery) were screened. The feces from donor mice were collected to make fecal bacteria fluid. Forty mice were selected and divided into 4 groups ( n=10 each) by the random number table method: control group (C group), antibiotic group (ABX group), resistant group (Res group), and sensitive group (Sen group). Group C received no treatment. In ABX group, compound antibiotics were given by intragastric gavage once a day for 5 consecutive days. In Res group, the fecal solution from sepsis-resistant mice 150 μl was given by gavage once a day for 3 consecutive days starting from 5 days after gavage administration of compound antibiotics, and then LPS 15 mg/kg was intraperitoneally injected. In Sen group, the fecal solution from sepsis-sensitive mice was given by gavage for 3 days (using the same method as previously described in Res group) starting from 5 days after gavage administration of compound antibiotics, and then LPS 15 mg/kg was intraperitoneally injected. The severity of sepsis was assessed and scored at 24 h after developing the model. The four limb grip strength was measured after fecal bacteria transplantation and at 24 h after developing the sepsis model. The Compound Muscle Action Potential (CMAP) of the gastrocnemius was measured at 24 h after developing the sepsis model. Then blood samples were collected for determination of the levels of interleukin-1 (IL-1), IL-6 and tumor necrosis factor α (TNF-α) in serum by enzyme-linked immunosorbent assay. The tissues of anterior tibial muscle and gastrocnemius muscle were obtained for determination of the expression of muscle-specific ring finger protein 1 (MuRF-1) and muscle atrophy box F protein (MAFbx) by Western blot. The diameter and cross-sectional area of gastrocnemius muscle fibers were measured after HE staining. The feces of mice were collected at 3 days after fecal bacteria transplantation, and DNA was extracted from mouse fecal samples for 16S rDNA sequencing and untargeted metabolomics analysis. Results:Compared with C group, the score for severity of sepsis was significantly increased, the four limb grip strength was decreased after developing the sepsis model, the serum IL-6 concentration was increased, and the diameter and cross-sectional area of gastnemius muscle fibers were decreased ( P<0.05), and no statistically significant changes were found in the other parameters in Res group, and no statistically significant changes were found in the indexes mentioned above in ABX group ( P>0.05). Compared with C group and Res group, the score for severity of sepsis was significantly increased, the four limb grip strength was decreased, the latency of CMAP was prolonged, and the amplitude of CMAP was decreased, the serum concentrations of IL-1, IL-6 and TNF-α were increased, the diameter and cross-sectional area of gastrocnemius muscle fibers were decreased, and the expression of MuRF-1 and MAFbx in anterior tibial muscle was up-regulated after developing the sepsis model in Sen group ( P<0.05). 16S rDNA sequencing of intestinal flora: Compared with Sen group, no significant change was found in Chao1 index, Good-coverage index and Simpson index in Res group ( P>0.05), Shannon index was increased ( P<0.05), and no significant change was found in β diversity in Res group ( P>0.05). LDA analysis showed that f_Akkermarisiaceae, o_Verrucomicrobiales, g_Akmansia, c_Verrucomicrobiae and p_Verrucomicrobiota were significantly enriched in Sen group, and g_Enterococcus and f_Enterococcaceae were significantly enriched in Res group ( P<0.05). Nontargeted metabolic analysis: The metabolite profiles in Res group and Sen group suggested that the model was well developed (R2Y>Q2Y). Compared with Sen group, 90 metabolites was significantly up-regulated and 88 down-regulated, significantly up-regulated metabolic substances including vitamin K1, gamma-tocopherol, and taurine in Res group ( P<0.05). The differential metabolite KEGG enrichment pathway included 2-oxocarboxylic acid metabolism and ubiquinone and other terpenoid-quinone biosynthesis ( P<0.05). Conclusions:Intestinal flora heterogeneity may be involved in the pathogenesis of acquired myasthenia in septic mice.

Objective:To investigate the in vitro viability of rabies virus in tissues and body fluid samples. Methods:The viability of rabies virus in tissues and suspensions was analyzed by virus titer determination method, direct immunofluorescence, RT-PCR and laboratory techniques for virus isolation.Results:With the increase of temperature, the viability of rabies virus in brain tissues and suspensions decreased gradually. Rabies virus lost infectivity after 30 min at 56℃, but remained viable in tissues for 7 d at 37℃. The virus showed no viability after 1 h at pH9.6. The rabies virus in suspensions could be completely inactivated after the stimulation with ethanol at a final concentration above 30%, sodium hypochlorite above 500 mg/L or benzalkonium bromide above 100 mg/L for 3 min. It was found that 80% acetone had the strongest inactivation effect on rabies virus in tissues, and no virus could be isolated after soaking for 4 h.Conclusions:Rabies virus was not tolerant to high temperature and relatively stable in the environment with pH6.8-7.4. Common disinfectants could kill the virus. This study provided detailed data about the viability of rabies virus in vitro, which would be conducive to the prevention and control of rabies.

Objective:To analyze the in vitro inhibitory effects of resveratrol on rabies virus. Methods:The challenge virus standard (CVS)-11 strain of rabies virus and BHK-21 cells were used to establish the infection model. In vitro inhibitory effects of resveratrol on rabies virus were analyzed at different stages of infection by direct immunofluorescence and cell fluorescence focus unit assay. Results:Without affecting cell growth, resveratrol could block the adsorption of virus, interfere with the entry of virus into cells and inhibit virus proliferation in a concentration-dependent manner. The inhibition rate could reach up to about 95%. The results of co-incubation experiment showed that 40 μmol/L resveratrol could directly kill the virus.Conclusions:This study indicated that resveratrol inhibited the activity of rabies virus in a concentration-dependent manner.

Objective:Objective The inhibitory effect of Niuhuang Qinggan Capsule on 2019-nCoV virus was studied to provide experimental evidence for drug screening and treatment of 2019-nCoV acute respiratory disease.Methods:The 2019-nCoV virus GS048 strain was isolated and cultured by Vero-E6 cells. The solution of Niuhuang Qinggan capsule was incubated with virus in vitro to determine the change of virus titer. The effect of Niuhuang Qinggan capsule on the proliferation of 2019-nCoV virus was determined by cell culture medium method.Results:It was found that the concentration of 274.3 μg/ml was not toxic to the cells when the concentration of drugs was lower. When the drug was incubated with virus, the titer of virus decreased from 10 4.4TCID 50/ml to 10 2.8TCID 50/ml. In vitro 2019-nCoV virus culture experiment showed that the addition of the drugs reduced the cytopathy, and the logarithmic value of virus titer decreased by 40% -50%. Conclusion:In this study, in vitro inhibition experiments suggest that Niuhuang Qinggan capsule has the potential to inhibit the proliferation of 2019-nCoV. It can be used as a candidate drug to further verify the therapeutic effect of the 2019-nCoV acute respiratory disease.

Objective:To obtain the high-efficiency expression of the biological active rabies virus nucleoprotein in the prokaryotic expression system.Methods:This experiment uses codon optimization technology to re-encode the nucleoprotein gene of rabies virus CTN-1 strain, artificially synthesize the full-length gene and clone it into pET-43.1a prokaryotic expression vector, induced expression in BL21 (DE3) strain of Escherichia coli( E. coli), and used Western blot to detect its reactogenicity. Results:The results showed that after induction, SDS-PAGE electrophoresis analysis showed that an obvious expression band appeared at a molecular weight of 50×10 3, which was consistent with the expected protein band size. Among them, the E. coli concentration A600 is about 0.5, and the expression yield is the highest (about 32.3%) when induced at 37℃ for 5 h. Nucleoprotein expression product is mainly inclusion body when it is expressed in large quantities. After purification by Ni 2+ chelating chromatography, the purity of the target protein can reach over 95%. The purified product was identified by Western blot and positively reacted with the sera of mice immunized with rabies vaccine, indicating that the prokaryotic expression of the CTN-1 strain nucleoprotein has biological activity. Conclusions:This experiment successfully established a high-efficiency expression method for the nucleoprotein of the CTN-1 strain in the prokaryotic expression system, and obtained high-purity target protein, which provides a basis for further clinical diagnosis and preparation of new vaccines.