OBJECTIVE:To prepare nifedipine (NF) hollow controlled-release microspheres and evaluate the quality. METH-ODS:Solvent diffusion volatilization method was used to prepare microspheres,using comprehensive scores of cumulative release in 2,12,24 h(Q2 h,Q12 h,Q24 h)as indexes,orthogonal test was designed to screen the carrier material ethyl cellulose(EC),poly-vinyl pyrrolidone(PVP)and main drug NF amounts;appearance,particle size distribution,drug loading,floating and cumulative release of the microspheres prepared by optimal formulation were evaluated and compared of in vitro release behavior with imported preparation of Nifedipine controlled-release tablets (Adalat?). RESULTS:The optimal formulation was as follow as NF 3.00 g, PVP 1.60 g,EC 15.65 g. Prepared NF hollow controlled-release microspheres were spherical in shape with particle size distribution of 24-40 mesh and drug loading of 8.66%;24 h floating rate in release medium was 97.93%,Q2 h,Q12 h,Q24 h were 20.49%, 52.90%,91.00%(RSD<10%,n=3). Compared with the imported preparation,similarity factor f2 values of cumulative release were higher than 50,showing in vitro drug-release was consistent with the zero-order kinetic equation (r=0.9993);n of Rit-ger-Peppas equation (r=0.9807) was 0.478. CONCLUSIONS:Prepare NF hollow controlled-release microspheres show similar drug-release behavior with the imported preparation,the drug is released by the combination of diffusion and erosion.

Objective:To explore if there is premature senescence of chondrocytes in patients with Kashin-Beck disease (KBD) and osteoarthritis.Methods:Five knee cartilage samples of KBD, osteoarthritis and control groups were collected, respectively, from the Second Affiliated Hospital of Xi'an Jiaotong University. DNA was then extracted from cartilage samples and DNA methylation was analyzed by Illumina Infinium HumanMethylation450 BeadChip. At the same time, based on genome-wide methylation data, the online DNA methylation aging clock calculator (https://dnamage.genetics.ucla.edu/home) was used to calculate the DNA methylation age (DNAm age) of samples, and the results were compared with their actual ages.Results:In the comparison between KBD group and control group, 1 212 differentially methylated CpG sites were found, including 497 hypermethylated CpG sites and 715 hypomethylated CpG sites, corresponding to 264 hypermethylated genes and 368 hypomethylated genes, respectively. In the comparison between osteoarthritis group and control group, 656 differentially methylated CpG sites were found, including 343 hypermethylated CpG sites and 313 hypomethylated CpG sites, corresponding to 177 hypermethylated genes and 174 hypomethylated genes, respectively. In the above comparison, 367 overlapped CpG sites (corresponding to 182 genes) were found, which were differentially methylated in both KBD and control groups and osteoarthritis and control groups. The results of DNA methylation aging clock showed that the average age acceleration differences between DNAm age and actual age of KBD, osteoarthritis and control groups were 2.549, 0.017, and - 5.364 years, respectively, the DNAm ages of KBD and osteoarthritis groups were greater than the actual ages.Conclusion:The chondrocytes show premature senescence in both KBD and osteoarthritis.

BACKGROUND: The isolated and purified mammary stem cells from Holstein dairy cows have been induced to differentiate into nerve cells, adipocytes and osteoblasts, further enriching their multi-directional differentiation potential, which is of great significance for the study on mammary stem cells. OBJECTIVE: To investigate the osteogenic potential of mammary stem cells from Holstein dairy cows. METHODS: Mammary stem cells from Holstein dairy cows were isolated and purified, which were provided by the Key Laboratory of Biological Manufacturing of Inner Mongolia Autonomous Region. The fourth generation of mammary stem cells were cultured for 21 days in an osteogenic induction medium, and identified by alizarin red staining and RT-PCR. RESULTS AND CONCLUSION: After osteogenic induction, the cell edge was indistinct, and there were some granular calcified nodules in the cells. The induced cells were positive for alizarin red staining. The positive expressions of Alpl and Bglap in the induced osteoblasts were detected, indicating that the mammary stem cells from Holstein dairy cows have the potential to differentiate into osteoblasts.

OBJECTIVE: To investigate the persistent damage of learning and memory ability after the cessation of sub-chronic manganese(Mn)-exposure in rats. METHODS: Specific pathogen free weaning male SD rats were randomly divided into control group and low-, medium-and high-dose groups based on body weight, with 6 rats in each group. Rats were intraperitoneally injected with Mn chloride(MnCl_2·4 H_2O) at the concentrations of 0, 5, 10, or 20 mg/kg body weight, 5 days per week for 6 weeks and continued to be observed for 12 weeks after the cessation of Mn-exposure. During the experiment, the body mass of the rats was weighed. Learning and memory ability was evaluated by a Morris water-maze task at the 6 th weeks of Mn-exposure(cessation of Mn-exposure of week 0), the 6 th and 12 th week of the cessation of Mn-exposure. The organ coefficients of heart, liver, spleen, kidney and testicles were evaluated after the cessation of Mn-exposure on week 12. RESULTS: The body mass of the high-dose group was lower than that of the other 3 groups(P<0.05) at the 4 th and 6 th week of Mn-exposure and the 2 nd week of the cessation of Mn-exposure. There was no significant difference in body mass between the groups(P>0.05) on the 12 th week of the cessation of Mn-exposure. The escape latency of high-dose group was higher than that of the control group(P<0.05), and the number of platform crossings in the low-, medium-and high-dose groups were fewer than that in the control group(P<0.05) after the cessation of Mn-exposure. The escape latency was shorter and the numbers of platform crossings were higher on the 6 th and 12 th week of the cessation of Mn-exposure(P<0.05) when compared with that of the 6 th week of Mn-exposure rats. There was no statistical significance in the organ coefficients of heart, liver, spleen, kidney and testicles among the 4 groups at the 12 th week of the cessation of Mn-exposure in rats(P>0.05).CONCLUSION: Sub-chronic Mn exposure can impair learning and memory ability of rats, and the damage persists after the cessation of Mn-exposure.

Objective:To study the therapeutic effect Tetrandrine (TET) on striatal injury caused by microwave radiation and underlying mechanism.Methods:C57BL/6N mice were randomly divided into blank control group (C), radiation control group (R), TET group (TET) and TET combined with radiation group (TET+ R). The mice of radiation group were exposed to 2.856 GHz 8 mW/cm2 microwave on whole-body for 15 min. TET (60 mg/kg) was injected intraperitoneally once a day for 3 consecutive days. The TET structure was verified by ultraviolet spectrophotometry. The open field experiment was used to detect the change of anxiety in mice. Histopathological and ultrastructural changes of the striatum were observed by light microscopy and transmission electron microscopy (TMT). Quantitative real-time PCR (qPCR) was used to detect gene expression changes of voltage-gated calcium channel (VGCC) subtype in the striatum.Results:The open field experiments showed that the time and distance of mice to explore the central region after microwave radiation were significantly lower than that before radiation ( t=4.60, 5.18, P<0.01), and the TET administration significantly improved these changes ( F=1.43, 4.37, P < 0.05). 7 d after microwave radiation, some neuronal nuclei in the striatum of mice contracted and could be stained deeply, which was more obvious in the globus pallidus area. The partial neuronal apoptosis, swelling and cavitation of glial cell mitochondria, blurring of synaptic gaps, and widening of perivascular gaps in the striatum were observed by TMT. The above lesions were significantly rescued after TET administration. But both microwave radiation and TET administration had no significant effect on the gene expressions of striatal VGCC ( P > 0.05). Conclusions:TET has a therapeutic effect on anxiety-like behavior and structural damage of striatum caused by microwave radiation, which is independent of the expression of striatal VGCC genes.

Objective:To investigate the clinical characteristics and correlation of sleep disturbances(SD)with cognitive impairment-associated cerebral small vascular disease(CSVD-CI)in elderly patients.Methods:In this cross-sectional study, 261 elderly CSVD-CI patients admitted to the Department of Neurology, Second Hospital of Tianjin Medical University between December 2019 and December 2021 were continuously enrolled.The Pittsburgh Sleep Index Scale(PSQI)was used to evaluate the overall sleep quality.Those with a PSQI score ≥7 was assigned to the CSVD-CI with sleep disturbances(CSVD-CI-SD)group, while those with a PSQI score <7 was assigned to the CSVD-CI without SD(CSVD-CI-NSD)group.The Montreal Cognitive Assessment(MoCA)was used to evaluate the cognitive function of patients with CSVD-CI, and scores on the overall cognitive function and various cognitive domains were compared between the CSVD-CI-SD group and the CSVD-CI-NSD group.Results:There were no significant differences between the CSVD-CI-SD group and the CSVD-CI-NSD group in sex ratio, age, education level and comorbidities( P>0.05). Compared with the CSVD-CI-NSD group, patients in the CSVD-CI-SD group took longer to fall asleep, had worse sleep efficiency, a shorter sleep duration, more obvious SD at night, worse sleep quality, more use of sleeping drugs, and more obvious daytime dysfunction(all P<0.05). Compared with the CSVD-CI-NSD group, the total MoCA score, attention score and orientation score in the CSVD-CI-SD group were significantly decreased( P<0.01). Correlation analysis results showed that the total MoCA score and attention in the CSVD-CI-SD group were negatively correlated with SD at night( r=-0.198, r=-0.115, P<0.05 for both), and orientation was negatively correlated with sleep quality( r=-0.170, P<0.05). Conclusions:The prevalence of SD is high in CSVD-CI patients, with CSVD-CI-SD patients showing more obvious overall cognitive, attention and orientation impairment in MoCA.Additionally, the total MoCA score and attention are negatively correlated with nighttime SD, and orientation is negatively correlated with sleep quality in CSVD-CI-SD patients.

Objective:To evaluate artificial intelligence constructed by deep convolutional neural network (DCNN) for the site identification in upper gastrointestinal endoscopy.Methods:A total of 21 310 images of esophagogastroduodenoscopy from the Cancer Hospital of Chinese Academy of Medical Sciences from January 2019 to June 2021 were collected. A total of 19 191 images of them were used to construct site identification model, and the remaining 2 119 images were used for verification. The performance differences of two models constructed by DCCN in the identification of 30 sites of the upper digestive tract were compared. One model was the traditional ResNetV2 model constructed by Inception-ResNetV2 (ResNetV2), the other was a hybrid neural network RESENet model constructed by Inception-ResNetV2 and Squeeze-Excitation Networks (RESENet). The main indices were the accuracy, the sensitivity, the specificity, positive predictive value (PPV) and negative predictive value (NPV).Results:The accuracy, the sensitivity, the specificity, PPV and NPV of ResNetV2 model in the identification of 30 sites of the upper digestive tract were 94.62%-99.10%, 30.61%-100.00%, 96.07%-99.56%, 42.26%-86.44% and 97.13%-99.75%, respectively. The corresponding values of RESENet model were 98.08%-99.95%, 92.86%-100.00%, 98.51%-100.00%, 74.51%-100.00% and 98.85%-100.00%, respectively. The mean accuracy, mean sensitivity, mean specificity, mean PPV and mean NPV of ResNetV2 model were 97.60%, 75.58%, 98.75%, 63.44% and 98.76%, respectively. The corresponding values of RESENet model were 99.34% ( P<0.001), 99.57% ( P<0.001), 99.66% ( P<0.001), 90.20% ( P<0.001) and 99.66% ( P<0.001). Conclusion:Compared with the traditional ResNetV2 model, the artificial intelligence-assisted site identification model constructed by RESENNet, a hybrid neural network, shows significantly improved performance. This model can be used to monitor the integrity of the esophagogastroduodenoscopic procedures and is expected to become an important assistant for standardizing and improving quality of the procedures, as well as an significant tool for quality control of esophagogastroduodenoscopy.

Objective:To investigate the role of a disintegrin and metalloprotease 12 (ADAM12) gene in chondrocyte injury in patients with Kashin-Beck disease (KBD) and its impact on genes related to insulin-like growth factor binding protein (IGFBP).Methods:Articular cartilage samples were obtained from 5 patients with KBD and 5 control subjects admitted to Honghui Hospital Affiliated to Xi'an Jiaotong University. Chondrocytes were extracted and cultured in vitro. Quantitative real-time PCR (qRT-PCR) and Western blotting were used to detect the expression levels of ADAM12 mRNA and protein in chondrocytes of patients with KBD and control subjects, respectively. Subsequently, ADAM12 gene overexpression was performed using lentivirus in chondrocytes of patients with KBD. MTT assay was used to detect changes in cell viability after ADAM12 gene overexpression, and qRT-PCR was used to detect the mRNA expression levels of chondrocyte differentiation related genes SRY-box transcription factor 9 (SOX9) and type Ⅱ collagen (COLⅡ), apoptosis-related gene B-cell lymphoma/leukaemia-2-associated X protein (BAX), and anabolic related genes IGFBP3 and IGFBP5. Results:The expression levels of ADAM12 mRNA and protein in chondrocytes of patients with KBD (0.57 ± 0.05, 0.81 ± 0.07) were significantly lower than those of control subjects (1.00 ± 0.00, 1.00 ± 0.00), and the differences were statistically significant ( t = - 24.50, - 3.61, P < 0.05). The results of MTT assay showed that the cell viability of chondrocytes in ADAM12 overexpression group (1.09 ± 0.05) was higher than that in empty vector control group (1.00 ± 0.08), and the difference was statistically significant ( t = 4.12, P = 0.031). The results of qRT-PCR showed that compared with empty vector control group, the mRNA expression levels of IGFBP3 (2.35 ± 0.79 vs 0.96 ± 0.25), IGFBP5 (2.13 ± 0.30 vs 0.98 ± 0.34), SOX9 (2.92 ± 0.51 vs 0.94 ± 0.36) and COLⅡ (6.45 ± 2.81 vs 0.87 ± 0.19) in ADAM12 overexpression group were significantly increased, and the differences were statistically significant ( t = 3.19, 5.16, 6.27, 4.10, P < 0.05); while the expression level of BAX mRNA (0.31 ± 0.06 vs 1.02 ± 0.22) was significantly decreased, and the difference was statistically significant ( t = - 11.16, P < 0.001). Conclusion:The ADAM12 gene may have a role in inhibiting apoptosis and promoting differentiation in chondrocyte injury in patients with KBD, and its overexpression can increase expression of IGFBP3 and IGFBP5.

Objective:To investigate the impact of matrix metalloproteinase 13 (MMP13) and low-density lipoprotein receptor-related protein 1 (LRP1) on autophagy of articular chondrocytes in patients with Kashin-Beck disease (KBD).Methods:Human articular cartilage samples obtained from 4 KBD patients and 4 control subjects were collected from Shaanxi Institute for Endemic Disease Prevention and Control, and the expression levels of MMP13 and LRP1 in cartilage tissue were determined using immunohistochemistry (IHC). Chondrocytes were extracted and cultured in vitro, the mRNA and protein expression levels of LRP1 and the autophagy related genes [Beclin 1 (BECN1), microtubule associated protein 1 light chain 3 (LC3)], cartilage injury related genes [MMP13, caspase-3 (CASP3)], chondrocyte differentiation related genes [collagen type Ⅱ alpha 1 chain (COL2A1), and SRY-box transcription factor 9 (SOX9)] were detected by real-time fluorescence quantitative PCR (qRT-PCR) and Western blot (WB), respectively. Chondrocytes from 3 KBD patients were extracted, and MMP13 gene silencing experiment was performed by RNA interference (RNAi) technology, the mRNA and protein expression levels of the above genes were detected by qRT-PCR and WB, respectively. In addition, the antagonist receptor associated protein (RAP) of LRP1 was used to block the LRP1 of human normal chondrocytes (C28/I2 cells), and qRT-PCR and WB were used to detect the mRNA and protein expression levels of LRP1, chondrocyte autophagy, differentiation and cartilage injury related genes, respectively. Results:The IHC results showed that the expression levels of MMP13 (1.67 ± 0.21, 0.59 ± 0.15, 0.51 ± 0.12) in the surface, middle, and deep layers of cartilage tissue of KBD patients were significantly higher than those of control subjects (0.25 ± 0.03, 0.26 ± 0.04, 0.06 ± 0.01), and the differences were statistically significant ( t = - 11.38, P < 0.001; t = - 3.82, - 6.26, P = 0.019, 0.003). The expression levels of LRP1 (0.10 ± 0.02, 0.03 ± 0.01, 0.17 ± 0.03) were significantly lower than those of control subjects (1.63 ± 0.40, 0.44 ± 0.12, 0.34 ± 0.08), and the differences were statistically significant ( t = 6.61, 5.61, 3.64, P = 0.003, 0.005, 0.022). The mRNA and protein expression levels of MMP13, CASP3, SOX9 in chondrocytes of KBD patients were significantly higher than those of control subjects, and the differences were statistically significant ( P < 0.05). The mRNA expression levels of LRP1, LC3, COL2A1 were significantly lower than those of control subjects, and the differences were statistically significant ( P < 0.05). After silencing the MMP13 gene in chondrocytes of KBD patients, there were no significant differences in the mRNA and protein expression levels of LRP1, BECN1, LC3, CASP3, COL2A1, and SOX9 ( P > 0.05). After blocking LRP1 with RAP, the protein expression levels of LRP1, BECN1, LC3, MMP13, COL2A1 and SOX9 in chondrocytes were significantly lower than those in control group ( P < 0.05). Conclusions:There is no direct correlation between MMP13 and abnormal autophagy of articular chondrocytes in KBD patients. After blocking LRP1, the expression of the autophagy related genes BECN1 and LC3 in chondrocytes is decreased.

Objective: To compare the long-term dental treatment effects, oral health habits and oral-health-related qualities of life of children treated under general anesthesia (GA) and passive restraint (PR), respectively. Methods: Twenty seven 2 to 4-year-old children treated under GA and thirty four children treated under PR were recruited in the Department of Pediatric Dentistry, Peking University School and Hospital of Stomatology. Up to 2 years after the treatment, a follow up assessment was conducted. The data of general information, dental plaque level and the unplanned treatments were recorded and analyzed. The questionnaire of oral health habits and early childhood oral health impact scale (ECOHIS) for each child was also completed and analyzed. The survival rate and median survival time of the deciduous teeth were calculated. Multivariate analysis was performed by using Cox proportional hazard model. Results: Twenty-five children under GA and 32 under PR were finally included, with a total of 1 098 deciduous teeth. The postoperative dental plaque indicesin both GA and PR groups had significantly improved than that of before the treatments (P=0.019, P<0.001). The oral health habits had also improved, and the improvement in PR group was more obvious than that in GA group. Totally 128 teeth (27.0%) appeared unplanned treatments in GA group and 232 teeth (37.2%) in PR group during the follow-ups. The new caries and recurrent caries in PR group were significantly more than that in GA group (P<0.001, P=0.012). No significant differences were found between the two groups in restoration failure, secondary caries and endodontic diseases (P=0.129, P=0.822, P=0.642). However, the time of occurrence of endodontic disease and secondary caries in GA group were significantly longer than that in PR group (P<0.01, P<0.001). The median survival time of teeth in GA group was 1 018 days comparing to 944 days in PR group. The difference was statistically significant (P<0.05). The survival rate was associated with such factors as decayed-missing-filled tooth (dmft), anterior or posterior teeth, feeding frequency, brushing habits and behavior management techniques. Conclusions The long-term dental treatment effects of children treated under GA was significantly better than that of PR group. Continuous reinforcement of proper dietary and oral hygiene habits might help in maintaining the long-term treatment effect.