The ultrasound probe is the most important accessory in ultrasound equipment,which adopted the piezoelectric vibrator as its core component,and it can complete ultrasonic emission and receiving echoes.A deep understanding for the operational characteristics of the probe's array elements is important premise that user can accurately judge the running situation of the probe.This study employed pulse-echo technique to detect sensitivity and capacitance of the array elements of ultrasonic probe.The detected data of 60 probes at China-Japan Friendship Hospital were collected,and 75%of the 60 probes existed residual couplant,and 80%of them existed indentation or damage to the outer skin.The tested results of leakage current indicated that 1 probe(1.7%)existed excessively high leakage current.In test for array elements,2 probes(3.4%)displayed partial damage at array elements,and 6 probes(10.2%)were irreparably damaged.The preventive test for the diagnostic equipment with ultrasound is helpful to establish a quality control system for ultrasound,and to provide analysis materials with reliability in using diagnostic equipment with ultrasound,and to also provide decision-making basis for equipment departments and clinical department of using equipment in hospital.

Objective To evaluate the application of modified chairside case-based learning(CBL)in the teaching of dental residents in the prosthodontic clinic.Methods Dental residents in Peking Union Medical College Hospital from September 2022 to September 2024 were enrolled.Traditional CBL was conducted in control group.Modified chairside CBL was conducted in test group.The scores of department rotation examination and questionnaire results were analyzed with t-test statistical analysis.Results The score of"patient reception"in test group was significantly higher than control group(P＜0.05).24 valid questionnaires were collected in two groups each.The rate of approval in test group was significantly higher than control group in the following items of questionnaire,including"reduce learning pressure or burden""improve the capacity of doctor-patient communication""improve the capacity of literature review""improve the capacity of group cooperation"(P＜0.05).Conclusions Modified chairside CBL has showed good teaching effects in improving the capacity of patient reception,doctor-patient communication,literature review,group cooperation,and meanwhile reduced learning pressure or burden.

Objective To explore the need and evaluate the effectiveness for head-simulator in the teaching of sto-matology within the eight-year program of clinical medicine.Methods Questionnaire survey was conducted among the students from 2017 cohort of the eight-year program of clinical medicine at Peking Union Medical College.The survey results were statistically analyzed and described.Results Totally 87.9％of the students believed that incor-porating head-simulator into the clinical practice course of stomatology were necessary,and 93.9％expressed will-ingness to join the training.Most students preferred to practice peri-odontal scaling and cavity preparation for caries during the simulated training sessions.The majority of students considered two or four class hours of simulated head teaching to be reasonable.The pilot head simulation training was successfully implemented;75.0％of the students acknowledged clear teaching and convincible demonstrations.All the trainees agreed that the head simulation course helped them better understand stomatology knowledge,stimulated their interest in learning and expressed a desire for increased head simulation sessions during clinical practice course of stomatology.Additionally,87.5％of the students preferred head simulation training course to be applied in classic clinical clerkships.Conclusions There is strong demand among students of eight-year program of clinical medicine for incorporating head-simulator into the education of stomatology.The pilot simulation training received positive evaluations.Further exploration is needed to optimize specific scheduling and content arrangement.

Objective To evaluate the efficacy,safety and patient compliance of a quadruple therapy containing minocycline compared with the traditional quadruple therapy in the treatment of Helicobacter(H.)pylori.Methods This study included 200 H.pylori positive patients,with 100 assigned to the minocycline-containing bismuth quadruple therapy group(LBMC group)and the other 100 to the amoxicillin-containing bismuth quadruple therapy group(LBAC group).After matching the two groups of patients using the propensity score matching(PSM)method,there were 86 cases in each group.Telephone follow-up was conducted on the 14th day after the start of treatment to record patient medication compliance and adverse drug reactions.A 13C urea breath test was performed for re-examination at least one month after completing the treatment plan and discontinuing medication.The intention-to-treat(ITT)and per-protocol(PP)analyses were used to compare the H.pylori eradication rates between the two groups,and Chi-square test and t-test were used for intergroup comparison.Results In the ITT analysis,the eradication rates of the LBMC group and the LBAC group were 89.5%(77/86,95%CI:82.9%～96.1%)and 82.6%(71/86,95%CI:74.4%～90.7%),respectively.In the PP analysis,the eradication rates were 92.6%(75/81,95%CI:86.8%～98.4%)and 88.8%(71/80,95%CI:81.7%～95.8%),respectively.The adverse reaction rate of the LBMC group was 27.9%(24/86),and that of the LBAC group 31.4%(27/86),showing no statistically significant difference(P>0.05).In terms of compliance,the LBMC group was 94.2%(81/86),and the LBAC group 93.0%(80/86),revealing no statistically significant difference(P>0.05).Conclusion As a first-line treatment for eradicating H.pylori,regimens containing minocycline demonstrate equivalent eradication rates to those containing amoxicillin,with similar safety and compliance.They can be used as an alternative treatment for patients allergic to penicillin.

Objective To evaluate the efficacy,safety and patient compliance of a quadruple therapy containing minocycline compared with the traditional quadruple therapy in the treatment of Helicobacter(H.)pylori.Methods This study included 200 H.pylori positive patients,with 100 assigned to the minocycline-containing bismuth quadruple therapy group(LBMC group)and the other 100 to the amoxicillin-containing bismuth quadruple therapy group(LBAC group).After matching the two groups of patients using the propensity score matching(PSM)method,there were 86 cases in each group.Telephone follow-up was conducted on the 14th day after the start of treatment to record patient medication compliance and adverse drug reactions.A 13C urea breath test was performed for re-examination at least one month after completing the treatment plan and discontinuing medication.The intention-to-treat(ITT)and per-protocol(PP)analyses were used to compare the H.pylori eradication rates between the two groups,and Chi-square test and t-test were used for intergroup comparison.Results In the ITT analysis,the eradication rates of the LBMC group and the LBAC group were 89.5%(77/86,95%CI:82.9%～96.1%)and 82.6%(71/86,95%CI:74.4%～90.7%),respectively.In the PP analysis,the eradication rates were 92.6%(75/81,95%CI:86.8%～98.4%)and 88.8%(71/80,95%CI:81.7%～95.8%),respectively.The adverse reaction rate of the LBMC group was 27.9%(24/86),and that of the LBAC group 31.4%(27/86),showing no statistically significant difference(P>0.05).In terms of compliance,the LBMC group was 94.2%(81/86),and the LBAC group 93.0%(80/86),revealing no statistically significant difference(P>0.05).Conclusion As a first-line treatment for eradicating H.pylori,regimens containing minocycline demonstrate equivalent eradication rates to those containing amoxicillin,with similar safety and compliance.They can be used as an alternative treatment for patients allergic to penicillin.

The ultrasound probe is the most important accessory in ultrasound equipment,which adopted the piezoelectric vibrator as its core component,and it can complete ultrasonic emission and receiving echoes.A deep understanding for the operational characteristics of the probe's array elements is important premise that user can accurately judge the running situation of the probe.This study employed pulse-echo technique to detect sensitivity and capacitance of the array elements of ultrasonic probe.The detected data of 60 probes at China-Japan Friendship Hospital were collected,and 75%of the 60 probes existed residual couplant,and 80%of them existed indentation or damage to the outer skin.The tested results of leakage current indicated that 1 probe(1.7%)existed excessively high leakage current.In test for array elements,2 probes(3.4%)displayed partial damage at array elements,and 6 probes(10.2%)were irreparably damaged.The preventive test for the diagnostic equipment with ultrasound is helpful to establish a quality control system for ultrasound,and to provide analysis materials with reliability in using diagnostic equipment with ultrasound,and to also provide decision-making basis for equipment departments and clinical department of using equipment in hospital.

Objective:To investigate the relationship between the expressions of checkpoint with forkhead-associated and ring finger(CHFR)and metastasis-associated protein 1(MACC1)and the sensitivity of patients with rectal cancer for neoadjuvant concurrent chemoradiotherapy(nCRT).Methods:The medical documents of 166 patients with rectal cancer admitted to First Hospital of Qinhuangdao from March 2017 to February 2022 were collected.All patients only received nCRT before surgery,and the radiotherapy adopted three-dimensional conformal intensity modulated radiotherapy,and chemotherapy adopted Capeox scheme.All patients successfully completed total mesorectal excision after 4-6 weeks of nCRT treatment.Immunohistochemical SP staining method was used to detect the protein expressions of CHFR and MACC1 in rectal cancer and its adjacent tissues.According to the tumor regressive grading(TRG)standard of the Joint Committee on Cancer Staging in the United States,75 patients who were grade 0-2 as TRG after nCRT were included in the nCRT insensitive group,and 91 patients who were grade 3-4 as TRG were included in the nCRT sensitive group.The expression levels of CHFR and MACC1 proteins in cancer tissues before and after treatment between the two groups were compared.And then,the relationship between clinically pathological characteristics of patients and nCRT sensitivity was analyzed,and the influencing factors of nCRT sensitivity were analyzed.The receiver operating characteristic(ROC)curves of them were drawn,and area under curve(AUC)values were calculated,and the predictive values of CHFR and MACC1 for the sensitivity of patients with rectal cancer to nCRT were further analyzed.Results:The CHFR positive expression rate in rectal cancer tissue was significantly lower than that in adjacent tissues of rectal cancer,and the MACC1 positive expression rate in rectal cancer tissue was significantly higher than that in adjacent tissues of rectal cancer(x2=81.373,87.150,P＜0.05),respectively.After 166 patients completed the nCRT treatment,there were 6 cases of TRG grade 0,8 cases of TRG grade 1,61 cases of TRG grade 2,59 cases of TRG grade 3 and 32 cases of TRG grade 4.The sensitivity rate of nCRT was 54.82%(91/166).The CHFR positive expression rate in the nCRT sensitive group was significantly higher than that in the nCRT insensitive group,and the MACC1 positive expression rate in the nCRT sensitive group was significantly lower than that in the nCRT insensitive group(x2=4.613,37.509,P＜0.05).The proportions of T4 stage and N+stage in the nCRT sensitive group were higher than those in the nCRT insensitive group,and the differences were statistically significant(x2=54.432,28.912,P＜0.05),respectively.The expressions of CHFR and MACC1 were respectively independent risk factor affected the sensitivity of patients with rectal cancer to nCRT[OR=2.456(95% CI:1.294-4.563),OR=3.281(95% CI:1.472-6.479),P＜0.05].The sensitivity and specificity of the combined detection of CHFR and MACC1 were respectively 65.89% and 69.46% in predicting the nCRT sensitivity for rectal cancer.The predictive value of the combined detection was higher than that of single CHFR detection and single MACC1 detection(AUC values of them were respectively 0.713,0.564,0.589,P＜0.05),respectively.Conclusion:CHFR and MACC1 are related to the sensitivity of patients with rectal cancer to nCRT,which means patients with high expression of CHFR and low expression of MACC1 are more sensitive to nCRT.Therefore,both of them may be indicators that predict the sensitivity of patients with rectal cancer to nCRT.

The family of voltage-gated potassium Kv2 channels consists of the Kv2.1 and Kv2.2 subtypes. Kv2.1 is constitutively highly phosphorylated in neurons and its function relies on its phosphorylation state. Whether the function of Kv2.2 is also dependent on its phosphorylation state remains unknown. Here, we investigated whether Kv2.2 channels can be phosphorylated by protein kinase C (PKC) and examined the effects of PKC-induced phosphorylation on their activity and function. Activation of PKC inhibited Kv2.2 currents and altered their steady-state activation in HEK293 cells. Point mutations and specific antibodies against phosphorylated S481 or S488 demonstrated the importance of these residues for the PKC-dependent modulation of Kv2.2. In layer II pyramidal neurons in cortical slices, activation of PKC similarly regulated native Kv2.2 channels and simultaneously reduced the frequency of action potentials. In conclusion, this study provides the first evidence to our knowledge that PKC-induced phosphorylation of the Kv2.2 channel controls the excitability of cortical pyramidal neurons.
Action Potentials ; HEK293 Cells ; Humans ; Protein Kinase C/metabolism* ; Pyramidal Cells/enzymology* ; Shab Potassium Channels/genetics*

Objective:To observe the expression of miRNA in retinal tissue of mice with oxygen-induced retinopathy (OIR), and screen miRNAs related to p21 and retinal neovascularization (RNV) formation.Methods:A experimental study. Forty healthy 7-day-old C57BL/6J mice were randomly divided into normal group and OIR group, with 20 mice in each group. The oxygen induced RNV model was constructed in the OIR group, and no treatment was performed in the normal group. At the age of 17 days, the mice were killed and the RNV of mice was observed by retinal fluorescence; the nuclei of vascular endothelium that broke through the inner limiting membrane of retina were counted under light microscope. The retinal tissues were taken for miRNA chip analysis to detect the differentially expressed miRNAs between the normal group and the OIR group. The resulting differential miRNA target genes were subjected to enrichment analysis based on gene annotation (GO) and Kyoto Encyclopedia of genes and genomes (KEGG); miRNAs and pathways that may be related to p21 were screened through Targetscan, MiRanda and MicroT-CDs database alignment. Independent sample t-test was used for pairwise comparison between groups. Results:Compared with the normal group, the area of nonperfusion area, RNV and the number of vascular endothelial nuclei that broke through the inner limiting membrane of the retina in the OIR group increased significantly, differences were statistically significant ( t=18.800, 9.025; P<0.05). Compared with the normal group, there were 54 miRNAs that were statistically differentially expressed in the OIR group, of which 47 were up-regulated and 7 were down-regulated. A total of 13 miRNAs related to p21 were screened from the alignment results of the three databases with the obtained differential miRNAs. According to the difference multiples, they were miR-7218-5p, miR-322-5p, miR-224-5p, miR-335-5p, miR-329-3p, miR-362-3p, miR-532-5p, miR-20b-5p, miR-20a-5p, miR-195a-5p, miR-423-5p, miR-497a-5p, and miR-129-5p. Differential miRNA target gene enrichment analysis yielded 1 112 go entries and 50 KEGG pathways, of which 50 go entries and 13 KEGG pathways were related to p21. Conclusion:13 miRNAs related to p21 were screened out in the OIR model.

Objective:To analyze the expression of miRNA involved in regulating retinal neovascularizationin in retinal tissue of oxygen-induced retinopathy (OIR) mice.Methods:Eighty healthy C57BL/6J mice were randomly divided into control group and OIR group at postnatal day 7(P7). Control group were not received any treatment and then exposed to room air. The OIR group was exposed to (75±2)% oxygen and then under room air at P12. Mice of all groups were euthanized at P17. Retinal neovasculation (RNV) was evaluated by counting the number of pre-retinal neovascular cells and analysing no perfusion area by immunofluorescent staining of the mouse retina.Total RNA was extracted from retinal tissue,and miRNA microarrays was performed to identify differentially expressed miRNA in the two groups. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed differential microRNA.Results:Compared with the control group,the retinal neovascular tufts and the no perfusion area were both significantly smaller than those in OIR group. The number of pre-retinal neovascular cell nuclei in retinas from control group were obviously lower than those in the retinas from OIR group ( t=9.025, P<0.05). MiRNA microarray analysis showed that 54 miRNA in OIR group showed statistically different expression in control group, 47 miRNA were up-regulated and 7 miRNA were down-regulated. The results of PCR were consistent with the trend of microarray. In GO analysis, 1112 items were significantly different ( P<0.05), and 65 items were significantly different in KEGG analysis of expression profile ( P<0.05). Conclusions:The miRNA expression in retinal tissue of OIR mice is different from that of normal mice, and these miRNA may be involved in the development of RNV. There are 54 miRNA expression differences in retinal tissue of OIR compared with normal mouse retinal tissue.