AIM:To observe the changes of atrial fibrillation susceptibility,and the remodeling of atrial myo-cyte action potential,ultrarapid activation delayed rectifier potassium current(IKur)and transient outward potassium cur-rent(Ito)in elderly mice,and to explore the mechanism of atrial fibrillation from the single cell electrophysiological level.METHODS:The C57BL/6J mice were divided into old group(20 months old)and young group(4 months old).Atrial fi-brillation was induced by esophageal atrial pacing.The atrial myocytes were isolated,and action potential and ion currents were recorded with patch-clamp technique.The associated proteins were detected by Western blot technique.RE-SULTS:(1)Compared with young mice,the total incidence of atrial fibrillation was significantly increased in old mice(20.0%at 4 months old vs 60.0%at 20 months old,P<0.01).(2)The action potential duration of atrial myocytes in aged mice was shortened,and more significantly after stimulation.(3)The density of Ito and IKur in atrial myocytes of aged mice increased significantly,from(12.6±1.4)pA/pF to(21.7±1.1)pA/pF,and from(7.5±1.5)pA/pF to(13.3±2.1)pA/pF,respectively(P<0.01).After stimulation,the current increased more significantly,especially in older atrial cells.Compared with the young mice,the steady-state activation curve of Ito in the atrial myocytes of the aged mice shifted towards the depolarization,suggesting that activation of Ito channels in the aged mice increased at the same voltage stimula-tion.(4)Compared with young group,the expression of KV4.2(generating Ito)and KV1.5(generating IKur)proteins in the atrial tissue of the mice in old group was significantly increased,and the expression of caveolin-3 and end-binding protein 1(EB1)was up-regulated,suggesting that the increases in KV4.2 and KV1.5 total channel proteins and effective proteins in the cell membrane might contribute to the increase in the remodeling of potassium currents in the elderly atrial myo-cytes.CONCLUSION:The incidence of atrial fibrillation in elderly mice is significantly augmented,which may be related to the increases in Ito and IKur in atrial myocytes.The remodeling of potassium currents in elderly atrial myocytes is one of the electrophysiological bases leading to the shortening of action potential duration and the occurrence of atrial fibrillation.

Objective:To explore the effects of magnolol on autophagy in intestinal Cajal cells and intestinal motility in rats with acute necrotizing pancreatitis (ANP).Methods:Forty-five Wistar rats were randomly divided into three groups by a random number table: control group, ANP group and magnolol intervention group, with 15 rats in each group. The ANP model was established by intraperitoneal injection of cerulein. The magnolol intervention group received a tail vein injection of 20 μg/kg magnolol ethanol solution 30 minutes after modeling. After 12 hours, ileal tissues were collected for pathological examination and scoring. Intestinal transit rate was measured using the carbon powder propulsion method, and isolated intestinal muscle strips were prepared to assess amplitude and frequency of spontaneous contraction. Oxidative stress markers in intestinal tissues, including superoxide dismutase (SOD) activity, malondialdehyde (MDA) and nitric oxide (NO) levels, were measured using xanthine oxidase, thiobarbituric acid, and enzymatic reduction assay kits, respectively. Cajal cells were isolated from intestinal smooth muscle tissues, and the expression of autophagy-related proteins (Beclin1, LC3Ⅱ, LC3Ⅰ, p62) and p-Kit was detected by Western blot. Double immunofluorescence staining was used to trace autophagy in Cajal cells.Results:The pathological scores of ileal tissues in the control, ANP, and magnolol intervention groups were (0.33±0.52), (4.83±0.41), and (3.50±0.55), respectively. The score in ANP group was significantly higher than that in the control group, while the score in the magnolol intervention group was lower than that in the ANP group, with statistically significant differences (all P value <0.05). Intestinal transit rate, amplitude and frequency of spontaneous contraction in the ANP group were significantly slower than those in the control group, while these parameters in the magnolol intervention group were significantly improved compared to the ANP group, with statistically significant differences (all P value <0.05). SOD activity in the control, ANP, and magnolol intervention groups were (73.8±8.1), (42.8±7.2), and (71.2±10.4) N/mg prot, respectively; NO levels were (1.72±0.26), (3.19±0.43), and (1.94±0.23) μmol/g prot; and MDA levels were (1.15±0.38), (3.84±0.30), and (1.68±0.33) nmol/mg prot. SOD activity in the ANP group was significantly lower than that in the control group, while NO and MDA contents were significantly higher. In the magnolol intervention group, SOD activity was significantly higher, and NO and MDA contents were significantly lower than those in the ANP group, with statistically significant differences (all P value <0.01). The levels of Beclin1, LC3Ⅱ/Ⅰ ratio, and p-Kit in the intestinal Cajal cells of ANP group were significantly higher than those in the intestinal Cajal cells of control group, while the p62 level was significantly lower. In the intestinal Cajal cells of magnolol intervention group, the levels of Beclin1, LC3Ⅱ/Ⅰ ratio, and p-Kit were significantly lower while the p62 level was significantly higher than those in the intestinal Cajal cells of ANP group, with statistically significant differences (all P value <0.01). The numbers of c-Kit/GFP-LC3 double-positive Cajal cells in the control group, ANP group, and magnolol intervention group were (9.59±5.06), (11.27±8.30), and (10.27±6.30), respectively. The ANP group had significantly more double-positive cells than the control group, while the magnolol intervention group had significantly less double-positive cells than the ANP group, with statistically significant differences (all P value <0.05). Conclusions:Excessive oxidative stress and autophagy in Cajal cells are important mechanisms underlying ANP-induced intestinal motility dysfunction. Magnolol can improve intestinal motility in ANP by antagonizing oxidative stress and reducing autophagy in Cajal cells. p-Kit may play a regulatory role in this process.

Objective:To digitally measure the three-dimensional (3D) size of primary tooth crowns and the dimensions of the dental arch in children with individual normal primary dentition, preliminarily obtaining baseline data on the 3D size of primary tooth crowns as well as the length and width of the dental arch, and their influence factors. This study aims to provide a data foundation for the design of reference models for primary dentition.Methods:From May to June 2021, 122 caries-free children aged 3.5-4.5 years with individual normal occlusion were selected from five kindergartens in Haidian District, Beijing. Impressions were taken and plaster models were cast. After preliminary screening, 67 eligible models were scanned to obtain digital dental models. Digital measurement software was used for landmark-based measurements. Parameters included 3D crown dimensions (mesiodistal diameter, buccolingual diameter, and occlusogingival height), dental arch dimensions (length and width at specific regions), and occlusal measurements (overjet and overbite at the primary central incisors, and Bolton index for anterior and full dentition). Gender differences in crown dimensions and bilateral symmetry of homologous teeth, as well as the correlations between arch dimensions and gender, height, weight, and body mass index (BMI) were analyzed.Results:The homonymous teeth of 67 children exhibited strong bilateral symmetry in all 3D dimensions ( P>0.05). Gender differences were observed in the buccolingual dimension for all deciduous molars except for the right mandibular first deciduous molar ( P<0.05). For the occlusogingival dimension, gender differences were found in the right maxillary first and second deciduous molars, left maxillary first deciduous molar, and left mandibular first and second deciduous molars ( P<0.05). For the mesiodistal dimension, only the left mandibular second deciduous molar and right mandibular deciduous canine showed gender differences ( P<0.05). All significant differences above indicated larger dimensions in boys compared to girls. In both maxillary and mandibular arches, the lengths and widths at various locations were significantly larger in boys than in girls ( P<0.05). Univariate correlation analysis revealed that body weight was positively correlated with the width of the terminal plane in both the maxilla and mandible and the total length of the mandibular dental arch, while BMI was positively correlated with the width of the maxillary terminal plane and the widths at all measured sites in the mandible ( P<0.05). Multiple regression analysis demonstrated that, after controlling for relevant variables, BMI was a significant positive predictor for the lengths and widths at various sites of the dental arch ( P<0.05), and height was a positive predictor for dental arch length ( P<0.05), as well as body weight was a positive predictor for the width in the molar region ( P<0.05). Overjet at the primary central incisors was 2.28 (1.57, 2.66) mm, and overbite was 1.13 (0.75, 1.92) mm. The anterior Bolton index was 0.79±0.03, and the overall Bolton index was 0.94±0.03. Conclusions:Primary tooth crowns of individual normal occlusion children demonstrate strong bilateral symmetry in homologous teeth. Most primary molars exhibit gender differences in buccolingual and occlusogingival dimensions, with larger values in boys. Arch dimensions (length and width) are consistently larger in boys.

Objective To investigate the distribution and antimicrobial resistance profiles of clinically isolated Haemophilus influenzae and Moraxella catarrhalis in hospitals across China from 2015 to 2021,and provide evidence for rational use of antimicrobial agents.Methods Data of H.influenzae and M.catarrhalis strains isolated from 2015 to 2021 in CHINET program were collected for analysis,and antimicrobial susceptibility testing was performed by disc diffusion method or automated systems according to the uniform protocol of CHINET.The results were interpreted according to the CLSI breakpoints in 2022.Beta-lactamases was detected by using nitrocefin disk.Results From 2015 to 2021,a total of 43 642 strains of Haemophilus species were isolated,accounting for 2.91％of the total clinical isolates and 4.07％of Gram-negative bacteria in CHINET program.Among the 40 437 strains of H.influenzae,66.89％were isolated from children and 33.11％were isolated from adults.More than 90％of the H.influenzae strains were isolated from respiratory tract specimens.The prevalence of β-lactamase was 53.79％in H.influenzae strains.The H.influenzae strains isolated from children showed higher resistance rate than the strains isolated from adults.Overall,779 strains of H.influenzae did not produce β-lactamase but were resistant to ampicillin(BLNAR).Beta-lactamase-producing strains showed significantly higher resistance rates to these antimicrobial agents than the β-lactamase-nonproducing strains.Of the 16 191 M.catarrhalis strains,80.06％were isolated from children and 19.94％isolated from adults.M.catarrhalis strains were mostly susceptible to both amoxicillin-clavulanic acid and cefuroxime,evidenced by resistance rate lower than 2.0％.Conclusions The emergence of antibiotic-resistant H.influenzae due to β-lactamase production poses a challenge for clinical anti-infective treatment.Therefore,it is very important to implement antibiotic resistance surveillance for H.influenzae and guide rational antibiotic use.All local clinical microbiology laboratories should actively improve antibiotic susceptibility testing and strengthen antibiotic resistance surveillance for H.influenzae.

This research investigated the contamination level,distribution of drug-resistant strains,and molecular epidemiologi-cal characteristics of Campylobacter,and further explored transmission pathways and prevention strategies.Cecum,chicken carcass,chicken product,and environmental samples,as well as swabs from workers'hands,were collected from a slaughterhouse in a large broiler group in the Jiaodong area between August 2023 and July 2024.Quantitative contamination assessment of Campylobacter in chicken carcasses and chicken products was performed.After microbial mass spectrometry identification,the representative strains of different links were selected for drug resistance testing and whole genome sequencing(WGS).On the basis of the sequencing results,the resistance genes,virulence genes,multilocus sequence typing(MLST),and phylogenetic characteristics of representative strains were analyzed.Homology comparisons were performed between isolates and strains from patients with diarrhea in the NCBI database.A total of 297 Campylobacter strains were isolated from 806 samples,and the overall detection rate was 36.85%.The detection rate of Campylobacter was highest in the evisceration process(47.33%),followed by the cutting process(35.64%).Overall,the Campylo-bacter detection rate first increased,then decreased,and subsequently increased.Drug sensitivity testing revealed that 90 isolates were resistant to nalidixic acid and ciprofloxacin,and 94.97%of isolates were resistant to tetracycline.WGS showed that both Campylo-bacter jejuni(C.jejuni)and Campylobacter coli(C.coli)carried many drug resistance and virulence genes.ST-14176 of C.jejuni was isolated for the first time herein.The predominant ST-8261 strain of C.jejuni and ST-860,ST-829,and ST-1586 strains of C.coli are known to cause human diarrhea.LOS expression genes associated with Guillain-Barré syndrome(GBS)were detected in both C.jejuni isolates from the slaughter chain and patients with GBS.Some strains exhibited close genetic relatedness to human-derived Campylo-bacter strains from the NCBI database.The detection rate of Campylobacter in the slaughterhouse first increased,then decreased,and subsequently increased,and the quantitative contamination level of each link was similar to the detection rate.Quantitative analysis of chicken carcasses/products revealed that the average bacterial load was highest in eviscerated carcasses(102.80 cfu/g),and the high-est amount of Campylobacter in chicken products reached 451.80 cfu/g.Abundant drug resistance genes and virulence genes were iden-tified,and the drug resistance genes were highly correlated with the drug resistance rate.Therefore,surveillance intensity and control measures for Campylobacter in slaughter processes should be strengthened.

Objective:To investigate the clinical efficacy of minimally invasive double anchoring combined with percutaneous kyphoplasty (PKP) for Kümmell disease.Methods:The clinical data of 24 patients with Kümmell disease who were treated with minimally invasive double anchoring combined with PKP in Cangzhou People's Hospital from October 2022 to March 2024 were retrospectively analyzed. Among them, there were 2 T 10 vertebrae, 5 T 11 vertebrae, 7 T 12 vertebrae, 6 L 1 vertebrae, and 4 L 2 vertebrae. There were 6 males and 18 females. The average age was 72.05±4.52 years (range, 66-80 years). The bone mineral density T value was -3.41±0.77 (range, -2.5-4.5). The stages of Li's Kümmell disease included 13 cases of stage II and 11 cases of stage III. The operation time, intraoperative blood loss, and volume of bone cement injected were recorded. The vertebral index, vertebral angle and Cobb angle of diseased segment were measured before and after operation. The visual analogue scale (VAS) was used to assess the degree of pain, the Oswestry disability index (ODI) and the Japanese Orthopaedic Association (JOA) low back pain scale were used to assess spinal function. The Medical Outcome Study short form 36 item health survey (SF-36) was used to assess the general health status of the patients. The postoperative symptom recovery was evaluated by Odom criteria. Results:The mean operative time of the 24 patients was 35.32±6.86 min, the injected volume of bone cement was 4.39±1.72 ml, and the intraoperative blood loss was 16.56±5.21 ml. All patients were followed up for 10 to 14 months, with an average of 11.7 months. Postoperative CT examination showed that the screw positions were satisfactory, and no loosening or displacement of bone cement mass occurred. On the first day after surgery, the vertebral body index, vertebral body angle and Cobb angle of diseased segment were 77.71%±2.75%, 12.40°±1.53° and 25.77°±4.49°, respectively, which represented significant improvements from the preoperative values of 43.09%±5.66%, 22.12°±2.92° and 46.98°±5.68° before surgery ( P<0.05). At the last follow-up, the values were 76.18%±2.32%, 12.41°±2.53°, 26.14°±4.87°, respectively, which were significantly improved compared with those before surgery ( P<0.05), but there was no statistical significance compared with the first day after surgery ( P>0.05). The VAS, ODI and JOA scores on the first day after surgery were 2.11±0.87 points, 22.46±5.49 points and 27.68±2.45 points, respectively, which were significantly improved compared with those before surgery 7.50±0.98 points, 76.25±8.56 points and 14.96±4.91 points ( P<0.05). At the last follow-up, the values were 2.26±0.88, 23.87±3.25 and 26.58±2.77, respectively, which were significantly improved compared with those before surgery ( P<0.05), and there was no statistical significance compared with the first day after surgery ( P>0.05). All 24 patients completed SF-36 scale assessment, and the results showed that there were statistically significant differences in physiological function, physiological role, physical pain, general health status, social function scores and mental health between the patients before surgery and the last follow-up ( P<0.05), while there were no statistically significant differences in vitality and emotional function ( P>0.05). At the last follow-up, the Odom criteria showed excellent results in 18 cases, good in 4 cases, and fair in 2 cases. Conclusions:The application of minimally invasive double anchoring (single nail fixation) combined with PKP in the treatment of Kümmell disease can effectively prevent the loosening and displacement of bone cement masses, and the fixation effect is satisfactory, which can restore the height of the injured vertebrum, reduce kyphosis and improve spinal function. The clinical symptoms of the patients were significantly improved, and the quality of life was enhanced.

Objective:To digitally measure the three-dimensional (3D) size of primary tooth crowns and the dimensions of the dental arch in children with individual normal primary dentition, preliminarily obtaining baseline data on the 3D size of primary tooth crowns as well as the length and width of the dental arch, and their influence factors. This study aims to provide a data foundation for the design of reference models for primary dentition.Methods:From May to June 2021, 122 caries-free children aged 3.5-4.5 years with individual normal occlusion were selected from five kindergartens in Haidian District, Beijing. Impressions were taken and plaster models were cast. After preliminary screening, 67 eligible models were scanned to obtain digital dental models. Digital measurement software was used for landmark-based measurements. Parameters included 3D crown dimensions (mesiodistal diameter, buccolingual diameter, and occlusogingival height), dental arch dimensions (length and width at specific regions), and occlusal measurements (overjet and overbite at the primary central incisors, and Bolton index for anterior and full dentition). Gender differences in crown dimensions and bilateral symmetry of homologous teeth, as well as the correlations between arch dimensions and gender, height, weight, and body mass index (BMI) were analyzed.Results:The homonymous teeth of 67 children exhibited strong bilateral symmetry in all 3D dimensions ( P>0.05). Gender differences were observed in the buccolingual dimension for all deciduous molars except for the right mandibular first deciduous molar ( P<0.05). For the occlusogingival dimension, gender differences were found in the right maxillary first and second deciduous molars, left maxillary first deciduous molar, and left mandibular first and second deciduous molars ( P<0.05). For the mesiodistal dimension, only the left mandibular second deciduous molar and right mandibular deciduous canine showed gender differences ( P<0.05). All significant differences above indicated larger dimensions in boys compared to girls. In both maxillary and mandibular arches, the lengths and widths at various locations were significantly larger in boys than in girls ( P<0.05). Univariate correlation analysis revealed that body weight was positively correlated with the width of the terminal plane in both the maxilla and mandible and the total length of the mandibular dental arch, while BMI was positively correlated with the width of the maxillary terminal plane and the widths at all measured sites in the mandible ( P<0.05). Multiple regression analysis demonstrated that, after controlling for relevant variables, BMI was a significant positive predictor for the lengths and widths at various sites of the dental arch ( P<0.05), and height was a positive predictor for dental arch length ( P<0.05), as well as body weight was a positive predictor for the width in the molar region ( P<0.05). Overjet at the primary central incisors was 2.28 (1.57, 2.66) mm, and overbite was 1.13 (0.75, 1.92) mm. The anterior Bolton index was 0.79±0.03, and the overall Bolton index was 0.94±0.03. Conclusions:Primary tooth crowns of individual normal occlusion children demonstrate strong bilateral symmetry in homologous teeth. Most primary molars exhibit gender differences in buccolingual and occlusogingival dimensions, with larger values in boys. Arch dimensions (length and width) are consistently larger in boys.

Objective:To investigate the clinical efficacy of minimally invasive double anchoring combined with percutaneous kyphoplasty (PKP) for Kümmell disease.Methods:The clinical data of 24 patients with Kümmell disease who were treated with minimally invasive double anchoring combined with PKP in Cangzhou People's Hospital from October 2022 to March 2024 were retrospectively analyzed. Among them, there were 2 T 10 vertebrae, 5 T 11 vertebrae, 7 T 12 vertebrae, 6 L 1 vertebrae, and 4 L 2 vertebrae. There were 6 males and 18 females. The average age was 72.05±4.52 years (range, 66-80 years). The bone mineral density T value was -3.41±0.77 (range, -2.5-4.5). The stages of Li's Kümmell disease included 13 cases of stage II and 11 cases of stage III. The operation time, intraoperative blood loss, and volume of bone cement injected were recorded. The vertebral index, vertebral angle and Cobb angle of diseased segment were measured before and after operation. The visual analogue scale (VAS) was used to assess the degree of pain, the Oswestry disability index (ODI) and the Japanese Orthopaedic Association (JOA) low back pain scale were used to assess spinal function. The Medical Outcome Study short form 36 item health survey (SF-36) was used to assess the general health status of the patients. The postoperative symptom recovery was evaluated by Odom criteria. Results:The mean operative time of the 24 patients was 35.32±6.86 min, the injected volume of bone cement was 4.39±1.72 ml, and the intraoperative blood loss was 16.56±5.21 ml. All patients were followed up for 10 to 14 months, with an average of 11.7 months. Postoperative CT examination showed that the screw positions were satisfactory, and no loosening or displacement of bone cement mass occurred. On the first day after surgery, the vertebral body index, vertebral body angle and Cobb angle of diseased segment were 77.71%±2.75%, 12.40°±1.53° and 25.77°±4.49°, respectively, which represented significant improvements from the preoperative values of 43.09%±5.66%, 22.12°±2.92° and 46.98°±5.68° before surgery ( P<0.05). At the last follow-up, the values were 76.18%±2.32%, 12.41°±2.53°, 26.14°±4.87°, respectively, which were significantly improved compared with those before surgery ( P<0.05), but there was no statistical significance compared with the first day after surgery ( P>0.05). The VAS, ODI and JOA scores on the first day after surgery were 2.11±0.87 points, 22.46±5.49 points and 27.68±2.45 points, respectively, which were significantly improved compared with those before surgery 7.50±0.98 points, 76.25±8.56 points and 14.96±4.91 points ( P<0.05). At the last follow-up, the values were 2.26±0.88, 23.87±3.25 and 26.58±2.77, respectively, which were significantly improved compared with those before surgery ( P<0.05), and there was no statistical significance compared with the first day after surgery ( P>0.05). All 24 patients completed SF-36 scale assessment, and the results showed that there were statistically significant differences in physiological function, physiological role, physical pain, general health status, social function scores and mental health between the patients before surgery and the last follow-up ( P<0.05), while there were no statistically significant differences in vitality and emotional function ( P>0.05). At the last follow-up, the Odom criteria showed excellent results in 18 cases, good in 4 cases, and fair in 2 cases. Conclusions:The application of minimally invasive double anchoring (single nail fixation) combined with PKP in the treatment of Kümmell disease can effectively prevent the loosening and displacement of bone cement masses, and the fixation effect is satisfactory, which can restore the height of the injured vertebrum, reduce kyphosis and improve spinal function. The clinical symptoms of the patients were significantly improved, and the quality of life was enhanced.

Objective To observe the effect of energy CT and color mapping to optimize displaying of ossification after lumbar interbody fusion.Methods A total of 76 patients who underwent lumbar fusion were retrospectively enrolled.According to the way of rescanning CT,the patients were divided into energy CT group(n=30)and traditional CT group(n=46).Subjective scoring of imaging quality of both groups on anatomic details,i.e.ossification of bone graft particles in the interbody fusion zone,cancellous bone growth near the endplate in the vertebral body,bone bridge connecting the interface between the fusion zone and the endplate in the vertebral body,as well as image artifacts were performed using a five-point scale.The image noise(SD value),and radiation dose represented by dose length product(DLP)were measured and compared between groups.Results Compared with traditional CT group,energy CT group had elevated subjective scores for anatomical details(4.50[4.28,4.50]vs.3.80[3.50,4.00])and image artifacts(4.30[4.00,4.50]vs.3.60[3.50,4.00]),while significantly lower SD value(37.22[34.90,38.85]HU vs.57.50[53.30,68.59]HU)and DLP(255.28[177.57,321.26]mGy·cm vs.327.60[298.13,415.95]mGy·cm)(all P＜0.05).Compared with grayscale images,images processed with color mapping demonstrated enhanced visualization of osseous details.Conclusion Energy CT after lumbar fusion could reduce image artifacts and improve the visualization of anatomical details at a lower radiation dose compared to conventional CT,while color mapping might further enhance the clarity of osseous details.

Body weight abnormalities, including overweight, obesity, and underweight, have become a dual public health challenge in Chinese adults: overweight and obesity lead to a variety of chronic complications, while underweight increases the risks of malnutrition, sarcopenia, and organ dysfunction. To systematically address these issues, multidisciplinary experts in endocrinology, sports science, nutrition, and psychiatry from various regions have held multiple weight management seminars. Based on the latest epidemiological data and clinical evidence, they expanded the guideline to include assessment and intervention strategies for underweight, in addition to the core content of obesity management. This guideline outlines the etiological mechanisms, evaluation methods, and multidimensional management strategies for overweight and obesity, covering key areas such as diagnosis and assessment, medical nutrition therapy, exercise prescription, pharmacological intervention, and psychological support. It is intended to provide a scientific and standardized approach to weight management across the adult population, aiming to curb the rising prevalence of obesity, mitigate complications associated with abnormal body weight, and improve nutritional status and overall quality of life.