Objective To classify the foot types of young Chinese males,extract characteristic indicators of foot types,and construct a standard foot type database.Methods Foot type data from 1 483 healthy young male individuals were collected.Spectral clustering algorithm was utilized to categorize foot types,and a deep neural network(DNN)was employed for training the classification model.Layer-wise relevance propagation(LRP)and the correlation coefficient method were combined to extract foot type features,and the differences in various foot type characteristics were compared.Results Spectral clustering yielded 4 distinct foot type categories.Foot type 1 was characterized by a high-arched foot with a prominent big toe,inwardly rotated 5th toe,and a high heel with a wide foot;foot type 2 was characterized by a narrow foot with hallux valgus;foot type 3 was characterized by a low-arched foot with hallux valgus;foot type 4 was characterized by a high-arched foot with a prominent big toe.By integrating interpretable neural networks and the correlation coefficient method,nine indicators were extracted from 27 foot type indicators,including the heel to the sole length,hallux height,navicular bone height,lateral malleolus height,hallux valgus angle,5th toe angle,dorsal foot circumference,heel angle,and longitudinal arch angle.The classification model constructed with these extracted indicators achieved an overall discrimination accuracy rate of 93.67％.Conclusions Chinese young males can be classified into four typical foot types.By examining the rearfoot,midfoot,and forefoot regions,nine key foot morphology parameters,including length,height,circumference,and angle,can be extracted.These parameters provide both theoretical and empirical support for establishing normative data on foot morphology for Chinese young males and for advancing biomechanical researches on the foot and ankle.

Objective To explore the correlation between single-leg standing posture control and ankle plantar flexor muscle stability,so as to provide a new theoretical basis for improving the ability of human posture control.Methods A total of 20 healthy male college students were randomly selected as the experimental subjects.The iBalance tester and training system was used to test the trajectory data of the center of pressure(COP)of the foot standing on one leg.The CON-TREX MJ multi-joint isokinetic test and training system was used to test the moment amplitude data during the contraction of ankle plantar flexor muscles.Univariate repeated measures variance analysis was used to analyze the standard deviation data of ankle plantar flexor moment amplitude between groups.The Pearson correlation coefficient was used to study the correlation.Results The greater the intensity of the muscle stabilization task performed by the ankle plantar flexor muscle,the greater the standard deviation of the moment amplitude.The C90 area was positively correlated with the coefficient of variation(CV)of the 10％maximum voluntary contraction(MVC)moment of ankleplantar flexor muscle(r=0.761,P＜0.05)during single-leg standing without interference.The C90 area was positively correlated with the CV(r=0.632,P＜0.05)of the 30％MVC moment of ankle plantar flexor muscle during single-leg standing.When the proprioception was interfered during single-leg standing,the C90 area was positively correlated with the CV(r=0.583,P＜0.05)of the 20％MVC moment amplitude of ankleplantar flexor muscle.Conclusions With the increasing difficulty of muscle strength stabilization performed by the ankle plantar flexor muscles,muscle stability decreases.There is a positive correlation between ankle plantar flexor strength stability and single-leg standing posture control.Compared with the case without interference,under visual and proprioceptive interference,an additional information input is reduced or disturbed,and it is more difficult to maintain body balance,and the ankle plantar flexor muscle needs a higher muscle stability in the force mode to participate in the posture control of the human body during single-leg standing.

Objective To explore the correlation between single-leg standing posture control and ankle plantar flexor muscle stability,so as to provide a new theoretical basis for improving the ability of human posture control.Methods A total of 20 healthy male college students were randomly selected as the experimental subjects.The iBalance tester and training system was used to test the trajectory data of the center of pressure(COP)of the foot standing on one leg.The CON-TREX MJ multi-joint isokinetic test and training system was used to test the moment amplitude data during the contraction of ankle plantar flexor muscles.Univariate repeated measures variance analysis was used to analyze the standard deviation data of ankle plantar flexor moment amplitude between groups.The Pearson correlation coefficient was used to study the correlation.Results The greater the intensity of the muscle stabilization task performed by the ankle plantar flexor muscle,the greater the standard deviation of the moment amplitude.The C90 area was positively correlated with the coefficient of variation(CV)of the 10％maximum voluntary contraction(MVC)moment of ankleplantar flexor muscle(r=0.761,P＜0.05)during single-leg standing without interference.The C90 area was positively correlated with the CV(r=0.632,P＜0.05)of the 30％MVC moment of ankle plantar flexor muscle during single-leg standing.When the proprioception was interfered during single-leg standing,the C90 area was positively correlated with the CV(r=0.583,P＜0.05)of the 20％MVC moment amplitude of ankleplantar flexor muscle.Conclusions With the increasing difficulty of muscle strength stabilization performed by the ankle plantar flexor muscles,muscle stability decreases.There is a positive correlation between ankle plantar flexor strength stability and single-leg standing posture control.Compared with the case without interference,under visual and proprioceptive interference,an additional information input is reduced or disturbed,and it is more difficult to maintain body balance,and the ankle plantar flexor muscle needs a higher muscle stability in the force mode to participate in the posture control of the human body during single-leg standing.

Objective To explore the effect of cognitive-motor dual tasks with different cognitive loads(none,simple and difficult)on activation of prefrontal cortex and static posture control in young man.Methods From June to July,2024,27 healthy male college students were recruited in Hebei Normal University.Static postural control parameters(C90 area),lower limb electromyography data(muscle energy proportion)and pre-frontal cortex hemodynamic signals of subjects under single task without cognitive load,dual-task with simple cognitive load,and dual-task with difficult cognitive load were collected using a balanced testing and training system,a wireless surface electromyography device,and functional near-infrared spectroscopy technology.Results The C90 areas of dual-tasks with simple and difficult cognitive load were smaller than that of the single task without cognitive load(P<0.05).The proportion of β band energy in the medial and lateral gastrocnemius mus-cles in the dual-task with simple cognitive load was greater than that in the single task without cognitive load(P<0.05),while the proportion of piper band energy in the lateral gastrocnemius muscle and tibialis anterior muscle was less(P<0.05).During dual-task with difficult cognitive load,the activation levels of bilateral ventro-lateral prefrontal cortex and right dorsolateral prefrontal cortex were higher than those in the single task without cognitive load(P<0.05).Conclusion Dual tasks with appopriate cognitive loads are effective on postural stability in young man.Simple cognitive load promote posture maintenance through optimizing the neuromuscular control of the lower limb muscle groups,while difficult cognitive load through activating the right prefrontal cortex involved in working memory and executive control,involving the neurocognitive compensatory.

Objective To explore the effect of cognitive-motor dual tasks with different cognitive loads(none,simple and difficult)on activation of prefrontal cortex and static posture control in young man.Methods From June to July,2024,27 healthy male college students were recruited in Hebei Normal University.Static postural control parameters(C90 area),lower limb electromyography data(muscle energy proportion)and pre-frontal cortex hemodynamic signals of subjects under single task without cognitive load,dual-task with simple cognitive load,and dual-task with difficult cognitive load were collected using a balanced testing and training system,a wireless surface electromyography device,and functional near-infrared spectroscopy technology.Results The C90 areas of dual-tasks with simple and difficult cognitive load were smaller than that of the single task without cognitive load(P<0.05).The proportion of β band energy in the medial and lateral gastrocnemius mus-cles in the dual-task with simple cognitive load was greater than that in the single task without cognitive load(P<0.05),while the proportion of piper band energy in the lateral gastrocnemius muscle and tibialis anterior muscle was less(P<0.05).During dual-task with difficult cognitive load,the activation levels of bilateral ventro-lateral prefrontal cortex and right dorsolateral prefrontal cortex were higher than those in the single task without cognitive load(P<0.05).Conclusion Dual tasks with appopriate cognitive loads are effective on postural stability in young man.Simple cognitive load promote posture maintenance through optimizing the neuromuscular control of the lower limb muscle groups,while difficult cognitive load through activating the right prefrontal cortex involved in working memory and executive control,involving the neurocognitive compensatory.

Objective To classify the foot types of young Chinese males,extract characteristic indicators of foot types,and construct a standard foot type database.Methods Foot type data from 1 483 healthy young male individuals were collected.Spectral clustering algorithm was utilized to categorize foot types,and a deep neural network(DNN)was employed for training the classification model.Layer-wise relevance propagation(LRP)and the correlation coefficient method were combined to extract foot type features,and the differences in various foot type characteristics were compared.Results Spectral clustering yielded 4 distinct foot type categories.Foot type 1 was characterized by a high-arched foot with a prominent big toe,inwardly rotated 5th toe,and a high heel with a wide foot;foot type 2 was characterized by a narrow foot with hallux valgus;foot type 3 was characterized by a low-arched foot with hallux valgus;foot type 4 was characterized by a high-arched foot with a prominent big toe.By integrating interpretable neural networks and the correlation coefficient method,nine indicators were extracted from 27 foot type indicators,including the heel to the sole length,hallux height,navicular bone height,lateral malleolus height,hallux valgus angle,5th toe angle,dorsal foot circumference,heel angle,and longitudinal arch angle.The classification model constructed with these extracted indicators achieved an overall discrimination accuracy rate of 93.67％.Conclusions Chinese young males can be classified into four typical foot types.By examining the rearfoot,midfoot,and forefoot regions,nine key foot morphology parameters,including length,height,circumference,and angle,can be extracted.These parameters provide both theoretical and empirical support for establishing normative data on foot morphology for Chinese young males and for advancing biomechanical researches on the foot and ankle.

Objective To investigate the effect and mechanism of shikonin on the proliferation,migration,invasion and apoptosis of human gastric cancer MGC803 cells.Methods The MGC803 cells in the logarithmic growth phase were randomly divided into the blank control group,shikonin group,shikonin+insulin-like growth factor-1(IGF-1)group,and shikonin+LY294002 group.Cells in the blank control group were cultured in drug-free medium,cells in the shikonin group were cultured in the medium containing shikonin with a final concentration of 10 μmol·L-1,cells in the shikonin+IGF-1 group were cultured in the medium containing shikonin with a final concentration of 10 μmol·L-1 and IGF-1 with a final concentration of 10 μmol·L-1,and cells in the shikonin+LY294002 group were cultured in the medium containing shikonin with a final concentration of 10 μmol·L-1 and LY294002 with a final concentration of 30 μmol·L-1.After 24 h of culture,the cell proliferation was detected by cell counting kit-8,the cell apoptosis was detected by flow cytometry,the cell migration was detected by scratch assay,and the cell invasion was detected by Transwell assay.The expression levels of B cell lymphoma-2(Bcl-2),Bcl-2 related X protein(Bax),cytochrome C(Cyt C),cleaved caspase-3,cleaved caspase-9,phosphoinositide 3 kinase(PI3K),phosphorylated PI3K(p-PI3K),protein kinase B(PKB),and phosphorylated PKB(p-PKB)proteins were measured by using Western blot.Results The MGC803 cell proliferation inhibition rate and apoptosis rate in the shikonin group were significantly higher than those in the blank control group(P＜0.05);the MGC803 cell proliferation inhibition rate and apoptosis rate in the shikonin+IGF-1 group were significantly lower than those in the shikonin group(P＜0.05);and the MGC803 cell proliferation inhibition rate and apoptosis rate in the shikonin+LY294002 group were significantly higher than those in the shikonin group(P＜0.05).The MGC803 cell scratch healing rate and the number of invasive cells in the shikonin group were significantly lower than those in the blank control group(P＜0.05);the MGC803 cell scratch healing rate and the number of invasive cells in the shikonin+IGF-1 group were significantly higher than those in the shikonin group(P＜0.05);and the MGC803 cell scratch healing rate and the number of invasive cells in the shikonin+LY294002 group were significantly lower than those in the shikonin group(P＜0.05).The relative expression level of Bcl-2 protein in MGC803 cells in the shikonin group was significantly lower than that in the blank control group(P＜0.05),while the relative expression levels of Bax,Cyt C,cleaved caspase-3 and cleaved caspase-9 proteins and the Bax/Bcl-2 ratio were significantly higher than those in the blank control group(P＜0.05);the relative expression level of Bcl-2 protein in MGC803 cells in the shikonin+IGF-1 group was significantly higher than that in the shikonin group(P＜0.05),while the relative expression levels of Bax,Cyt C,cleaved caspase-3 and cleaved caspase-9 proteins and the Bax/Bcl-2 ratio were significantly lower than those in the shikonin group(P＜0.05);and the relative expression level of Bcl-2 protein in MGC803 cells in the shikonin+LY294002 group was significantly lower than that in the shikonin group(P＜0.05),while the relative expression levels of Bax,Cyt C,cleaved caspase-3 and cleaved caspase-9 proteins and the Bax/Bcl-2 ratio were significantly higher than those in the shikonin group(P＜0.05).The relative expression levels of p-PI3K and p-PKB proteins and the ratios of p-PI3K/PI3K and p-PKB/PKB in MGC803 cells in the shikonin group were significantly lower than those in the blank control group(P＜0.05),and there was no statistically significant difference in the relative expression levels of PI3K and PKB proteins in MGC803 cells between the shikonin group and the blank control group(P＞0.05);the relative expression levels of p-PI3K and p-PKB proteins and the ratios of p-PI3K/PI3K and p-PKB/PKB in MGC803 cells in the shikonin+IGF-1 group were significantly higher than those in the shikonin group(P＜0.05),and there was no statistically significant difference in the relative expression levels of PI3K and PKB proteins in MGC803 cells between the shikonin+IGF-1 group and the shikonin group(P＞0.05);and the relative expression levels of p-PI3K and p-PKB proteins and the ratios of p-PI3K/PI3K and p-PKB/PKB in MGC803 cells in the shikonin+LY294002 group were significantly lower than those in the shikonin group(P＜0.05),and there was no statistically significant difference in the relative expression levels of PI3K and PKB proteins in MGC803 cells between the shikonin+LY294002 group and the shikonin group(P＞0.05).Conclusion Shikonin can inhibit the proliferation,migration and invasion and promote the apoptosis of human gastric cancer MGC803 cells,which may be related to its inhibition of the PI3K/PKB signaling pathway.

Objective: To analyze the epidemiological characteristics and related factors of hepatitis C in Beijing City from 2004 to 2021. Methods: Descriptive epidemiological method and Joinpoint regression were used to analyze the trend and other epidemiological characteristics of hepatitis C in Beijing City from 2004 to 2021 in National Notifiable Disease Reporting System. According to a 1∶1 matched case-control study design, logistic regression was used to investigate the risk factors of hepatitis C infection in 2021. Results: From 2004 to 2021, the reported incidence of hepatitis C in Beijing City ranged from 2.37/100 000 to 10.46/100 000. The reported cases were mainly aged 30-60 years, and most of them were chronic. The reported incidence of hepatitis C showed an initial increase from 2004 to 2006 (APC=45.37%, 95%CI:-1.56%-114.69%), and declined after 2006 (APC=-9.21%, 95%CI:-10.70%-7.70%). Logistic analysis showed that history of surgery (OR=1.84, 95%CI: 1.08-3.14) and previous blood transfusion (OR=34.22, 95%CI: 8.05-145.41) were risk factors for hepatitis C infection. Conclusion: The reported incidence of hepatitis C in Beijing City increases first and decreases later. It currently remains at a low level. The risk factors of infection are surgery and blood transfusion history. Safe blood supply and preventing iatrogenic transmission should be focused on the prevention of hepatitis C transmission.
Humans ; Beijing/epidemiology* ; Case-Control Studies ; Hepatitis C/prevention & control* ; Risk Factors ; Incidence

Objective: To investigate the infection sources and the transmission chains of three outbreaks caused by 2019-nCoV Omicron variant possibly spread through cross-border logistics in Beijing. Methods: Epidemiological investigation and big data were used to identify the exposure points of the cases. Close contacts were traced from the exposure points, and the cases' and environmental samples were collected for nucleic acid tests. Positive samples were analyzed by gene sequencing. Results: The Omicron variant causing 3 outbreaks in Beijing from January to April, 2022 belonged to BA.1, BA.1.1 and BA.2. The outbreaks lasted for 8, 12 and 8 days respectively, and 6, 42 and 32 cases infected with 2019-nCoV were reported respectively. International mail might be the infection source for 1 outbreak, and imported clothes might be the infection sources for another 2 outbreaks. The interval between the shipment start time of the imported goods and the infection time of the index case was 3-4 days. The mean incubation period (Q₁, Q₃) was 3 (2,4) days and the mean serial interval (Q₁, Q₃) was 3 (2,4)days. Conclusions: The 3 outbreaks highlighted the risk of infection by Omicron variant from international logistics-related imported goods at normal temperature. Omicron variant has stronger transmissibility, indicating that rapid epidemiological investigation and strict management are needed.
Humans ; Beijing ; SARS-CoV-2 ; COVID-19 ; Disease Outbreaks ; China/epidemiology*

Objective: To identify the risk factors in mortality of pediatric acute respiratory distress syndrome (PARDS) in pediatric intensive care unit (PICU). Methods: Second analysis of the data collected in the "efficacy of pulmonary surfactant (PS) in the treatment of children with moderate to severe PARDS" program. Retrospective case summary of the risk factors of mortality of children with moderate to severe PARDS who admitted in 14 participating tertiary PICU between December 2016 to December 2021. Differences in general condition, underlying diseases, oxygenation index, and mechanical ventilation were compared after the group was divided by survival at PICU discharge. When comparing between groups, the Mann-Whitney U test was used for measurement data, and the chi-square test was used for counting data. Receiver Operating Characteristic (ROC) curves were used to assess the accuracy of oxygen index (OI) in predicting mortality. Multivariate Logistic regression analysis was used to identify the risk factors for mortality. Results: Among 101 children with moderate to severe PARDS, 63 (62.4%) were males, 38 (37.6%) were females, aged (12±8) months. There were 23 cases in the non-survival group and 78 cases in the survival group. The combined rates of underlying diseases (52.2% (12/23) vs. 29.5% (23/78), χ²=4.04, P=0.045) and immune deficiency (30.4% (7/23) vs. 11.5% (9/78), χ²=4.76, P=0.029) in non-survival patients were significantly higher than those in survival patients, while the use of pulmonary surfactant (PS) was significantly lower (8.7% (2/23) vs. 41.0% (32/78), χ²=8.31, P=0.004). No significant differences existed in age, sex, pediatric critical illness score, etiology of PARDS, mechanical ventilation mode and fluid balance within 72 h (all P>0.05). OI on the first day (11.9(8.3, 17.1) vs.15.5(11.7, 23.0)), the second day (10.1(7.6, 16.6) vs.14.8(9.3, 26.2)) and the third day (9.2(6.6, 16.6) vs. 16.7(11.2, 31.4)) after PARDS identified were all higher in non-survival group compared to survival group (Z=-2.70, -2.52, -3.79 respectively, all P<0.05), and the improvement of OI in non-survival group was worse (0.03(-0.32, 0.31) vs. 0.32(-0.02, 0.56), Z=-2.49, P=0.013). ROC curve analysis showed that the OI on the thind day was more appropriate in predicting in-hospital mortality (area under the curve= 0.76, standard error 0.05,95%CI 0.65-0.87,P<0.001). When OI was set at 11.1, the sensitivity was 78.3% (95%CI 58.1%-90.3%), and the specificity was 60.3% (95%CI 49.2%-70.4%). Multivariate Logistic regression analysis showed that after adjusting for age, sex, pediatric critical illness score and fluid load within 72 h, no use of PS (OR=11.26, 95%CI 2.19-57.95, P=0.004), OI value on the third day (OR=7.93, 95%CI 1.51-41.69, P=0.014), and companied with immunodeficiency (OR=4.72, 95%CI 1.17-19.02, P=0.029) were independent risk factors for mortality in children with PARDS. Conclusions: The mortality of patients with moderate to severe PARDS is high, and immunodeficiency, no use of PS and OI on the third day after PARDS identified are the independent risk factors related to mortality. The OI on the third day after PARDS identified could be used to predict mortality.
Female ; Male ; Humans ; Child, Preschool ; Infant ; Child ; Critical Illness ; Pulmonary Surfactants/therapeutic use* ; Retrospective Studies ; Risk Factors ; Respiratory Distress Syndrome/therapy*