BACKGROUND:The elastic modulus of traditional bone implants is large and does not match the elastic modulus of human bone,which will cause a stress shielding effect and lead to bone resorption.The trabecular scaffold of the triply periodic minimal surface with radial gradient has elastic modulus matching with human cancellous bone,and its yield strength is greater than that of human cortical bone,which provides a new choice for the design of bone scaffold. OBJECTIVE:Triply periodic minimal surface structure with radial gradient was constructed by the implicit surface method.The sample was manufactured by laser selective melting technology,and the quasi-static compression test was carried out to obtain trabecular scaffolds with mechanical properties matching human bones. METHODS:Four types of the trabecular scaffolds of the triply periodic minimal surface with a radial gradient of G,I,P and D were established by the implicit surface method.Samples were manufactured by laser selective melting technology.We observed the surface morphology of the molded sample,evaluated the molding quality,conducted a quasi-static compression test,and evaluated the mechanical properties of the samples. RESULTS AND CONCLUSION:The quasi-static compression test results showed that compared with the four triply periodic minimal surface scaffolds,the platform stress of the G scaffold had less fluctuation and no failure or fracture,indicating that the G scaffold had the best plasticity.The mechanical properties of the G scaffolds with 45%,55%and 65%porosities were analyzed.It was found that the elastic modulus of G scaffolds with 55%porosity was within the range of elastic modulus of human cancellous bone(0.022-3.7 GPa),and the yield strength was close to the maximum yield strength of human cortical bone(187.7-222.3 MPa).In conclusion,G triply periodic minimal surface scaffold with 55%porosity can reduce the stress shielding effect,bear a higher body load,improve the stability of the implant,and prolong the service life of the implant.

BACKGROUND:Vertebral compression fracture is a common disease in the current orthopedic field.However,the occurrence of re-fracture in neighboring vertebrae after surgery is a problem that cannot be ignored,which has a serious impact on the normal life of patients. OBJECTIVE:The aim of this study is to establish four postoperative models with different recovery heights using computed tomography images.By using finite element analysis,we derived the stresses on the neighboring vertebrae at different recovery heights and further explored the importance of postoperative recovery of the height of the injured vertebrae. METHODS:A finite element model of the thoracolumbar spine(T11-L3)was established and validated,on the basis of which four postoperative finite element models of L1 with different recovery heights of 100%,80%,60%,and 40%were constructed,in which the cement capacity varied with the recovery height.The specific models are as follows:Model 1 was the postoperative model with normal recovery height,and the cement capacity was 8.3 mL.Model 2 was the postoperative model in which 20%of the anterior height of the L1 was removed and the posterior convexity angle became 10.41°,and the cement capacity was 6.9 mL.Model 3 was the postoperative model in which 40%of the anterior height of the L1 was removed and the posterior convexity angle became 20.17°,and the cement capacity was 4.7 mL.Model 4 was a postoperative model with 60%of the L1 anterior height removed and the posterior convexity angle changed to 28.85°,with a cement capacity of 3.6 mL.For evaluation of the postoperative model,we applied a moment of 7 Nm and an axial force of 500 N.The followings were recorded and analyzed:peak stresses in the L2 upper endplate and T12 lower endplate;peak stresses in the L2 and T12 cancellous bone. RESULTS AND CONCLUSION:(1)The highest peak stresses for each condition of the L2 upper endplate,T12 lower endplate,L2 cancellous bone,and T12 cancellous bone occurred in Model 1 and Model 4.In particular,the T12 lower endplate,except for the posterior extension condition,the anterior flexion,left and right lateral bending,and left and right rotation conditions all reached their highest peak stresses in Model 4,with stresses of 50.3,33.1,44.9,34.3,and 31.9 MPa.(2)Based on the peak stresses in the adjacent vertebral endplates and cancellous bone,after excluding Model 1 and Model 4,the minimum peak stresses for most of the conditions appeared in the Model 2,and the minimum peak stresses appeared in the Model 2 in 66.6%of the cases,especially in the upper endplates of the L2 and cancellous bone except for the posterior extension condition,the minimum peak stresses all appeared on the Model 2.(3)Therefore,controlling the recovery height at about 100%and 40%of the original height was a dangerous recovery height,which had a greater impact on the neighboring vertebrae.Controlling the recovery height at about 80%of the original height may be a more ideal choice.With a recovery height of about 80%of the original height,the adjacent vertebrae are subjected to less stress,thus reducing the risk of re-fracture of the adjacent vertebrae in the patient.

OBJECTIVES: The development and validation of the specific health literacy assessment tool for older adults is the basis for conducting the research on health literacy among older adults. The existing health literacy assessment scale for older adults in Chinese mainland has some limitations, such as too many items and poor compliance during the survey. It is necessary to develop or introduce simplified assessment tools to support large-scale surveys in the future. This study aims to modify the brief health literacy assessment scale compiled by Taiwan scholars, and to conduct the test for the reliability, validity and the measurement equivalence across gender in the older population in mainland China. METHODS: From March to April 2021, 508 older adults from Jinan, Shandong Province, China were selected by cluster sampling method to conduct a questionnaire survey using the brief health literacy assessment scale and health-promoting lifestyle profile. After 4 weeks, 83 of them were selected for retesting. SPSS 25.0 statistical software was used for descriptive analysis, item analysis, exploratory factor analysis, correlation analysis, and reliability test, and Mplus 8.0 was used for confirmatory factor analysis and gender measurement equivalence test. RESULTS: Each item of the scale had good discrimination, and there were significant differences in the scores of each item between high score and low score groups (P<0.05), and the coefficient of correlation between the scores of each item and the total score was between 0.721 and 0.891. Exploratory factor analysis extracted a factor with a characteristic root greater than 1, and the cumulative variance interpretation amount was 67.94%. The confirmatory factor analysis showed that the single factor structure fit was good [χ2/df was 2.260, the Tucker-Lewis index was 0.973, the comparison fit index (CFI) was 0.982, and the root mean square error of approximation (RMSEA) was 0.071]. The multi-group confirmatory factor analysis results showed that the brief health literacy assessment scale's configural equivalence, weak equivalence, and strong equivalence models were all accepted. The comparison results of measurement equivalence models showed that the changes of RMSEA were less than 0.015, and the changes of CFI were less than 0.01, indicating that the brief health literacy assessment scale had measurement equivalence between different gender groups. Cronbach's α coefficient was 0.945, and the test-retest reliability was 0.946. The correlation coefficient between health literacy and health-promotion lifestyles was 0.557 (P<0.05). CONCLUSIONS The brief health literacy assessment scale has good reliability, validity, and measurement equivalence across gender, and can be used as an effective measurement tool for the health literacy of the older people in Chinese mainland.
Humans ; Aged ; Reproducibility of Results ; Health Literacy/methods* ; Psychometrics ; Surveys and Questionnaires ; Asian People ; China ; Factor Analysis, Statistical

Objective:To investigate the effect of long-term chronic ethanol consumption on the spontaneous discharge activity of Purkinje cells in the cerebellar cortex of mice.Methods:Fifty 3-week-old ICR mice, regardless of gender, were divided into control group and ethanol group according to the random number table method, with 25 mice in each group. The mice in ethanol group were administered 20% ethanol (1.6 g/kg, once a day) by gavage, and the control group mice were given the same volume of 0.9% sodium chloride solution by gavage, and the gavage cycle was 28 days.The electrical activity of cerebellar Purkinje cells induced by sensory stimulation was recorded by patch clamp amplifier and data acquisition software. Statistical analysis was conducted by Clampfit 10.3 software and SPSS 22.0 software, t-test and one-way ANOVA were used to compare the data between the two groups and the data before and after intervention of each group. Results:The electrophysiological results showed that the spontaneous simple spike discharge frequency of Purkinje cells in the cerebellar cortex of mice in ethanol group was lower than that of the control group ((26.8±2.5)%, (34.6±4.7)%; t=26.08, P<0.05), and the coefficient of variation was higher than that of the control group ((27.3±3.3)%, (19.2±2.3)%; t=22.95, P<0.05). After cerebral surface perfusion of GABAA receptor antagonist, the frequency of simple peak potentials in the cerebellar cortex of ethanol mice was higher than before administration ( t=10.19, P<0.05), and the coefficient of variation was lower than before administration ( t=28.36, P<0.05). After brain surface perfusion of GABAA receptor antagonist, there was no significant change in the spontaneous simple peak discharge frequency of cerebellar Purkinje cells in the control group( P>0.05), and the coefficient of variation decreased compared to before administration ( t=6.95, P<0.05). After administering AMPA receptor antagonists on the surface of the brain, there were no significant changes in the discharge frequency and coefficient of variation in both the ethanol group and control group compared to before administration (both P>0.05). After simultaneously blocking AMPA and GABAA receptors, it was found that the spontaneous discharge frequency in ethanol group increased after administration compared to before administration((107.3±4.3)%, (99.7±3.7)%, P<0.05), and the increased value of frequency in the ethanol group was also higher than that of control group ( P<0.05). After simultaneously blocking AMPA and GABAA receptors, the coefficient of variation of the alcohol group and the control group mice were both lower than those before administration (both P<0.05), and the decrease in the alcohol group was higher than that in the control group ( P<0.05). Conclusion:Chronic ethanol exposure significantly inhibited the spontaneous discharge of Purkinje cells in the cerebellum, and the enhancement of inhibitory components was achieved by the inhibitory input mediated by GABAA receptors.

Objective:To investigate the long-term alcohol consumption on synaptic plasticity of mossy fiber-granule cells in cerebellar cortex and motor coordination function in mice.Methods:Thirty healthy male ICR mice aged 6-8 weeks were divided into saline group (control group)and alcohol consumption group(alcohol group) according to random number table with 15 in each group. The mice in alcohol group were injected intraperitoneally with 15% ethanol (1.6 g/kg), while the mice in control group were injected with the same volum of normal saline, all mice were injected intraperitoneally once a day for 28 consecutive days. Walking obstacle test and rotating rod fatigue test were used to observe the motor coordination ability and learning ability of mice. Electrophysiological patch clamp technique was used to detect the field potential changes of long-term synaptic plasticity induced by blowing stimulation. SPSS 22.0 software was used for statistical analysis.Independent sample t-test, paired t-test and repeated measurement analysis of variance were used for comparison between the two groups before and after intervention. Results:The electrophysiological results showed that the amplitude percentage of field potential N1 wave in the control group after blowing stimulation was (130.4±3.3)%, which was higher than that before stimulation ((100.6±2.7)%) ( t=27.07, P<0.01). And the percentage of area under N1 standardized waveform after stimulation ((128.8±4.5)%) was greater than that before stimulation ((100.2±3.5)%) ( t=19.43, P<0.01). There was no significant difference in the amplitude percentage of N1 wave in alcohol group ((97.8±4.3)%) after blowing stimulation compared with that before stimulation ((99.5±5.6)%) ( t=0.93, P>0.05). And also there was no significant difference in the area percentage under N1 wave after stimulation ((96.8±3.6)%) compared with that before stimulation ((100.2±4.2)%) ( t=2.38, P>0.05). The results of walking obstacle test showed that the total number of errors (3.14±0.19) in the alcohol group was higher than that in the control group(1.52±0.29) ( t=17.87, P<0.01), and the total error time ((63.85±9.34) ms) was longer than that in the control group ((28.93±7.21) ms) ( t=11.45, P<0.01). The results of repeated measurement analysis of variance showed that there was an interaction between time and group in the falling speed and falling latency of the two groups of mice in the rotating rod fatigue experiment ( F=4.5, 455.1, both P<0.05). The drop speed of mice in the alcohol group was significantly lower than that in the control group from day 1 to 7 (all P<0.05). The fall latency of mice in the alcohol group from day 1 to 7 was shorter than that in the control group, and the difference was statistically significant (all P<0.05). Conclusion:Long-term alcohol consumption impairs synaptic plasticity in the granular layer of mice and leads to a significant decline in motor coordination and motor learning ability.

Background Essential and non-essential elements have an important impact on the development of the central nervous system during fetal development. Due to their less developed brain, preterm infants are more sensitive to element exposure, and are high-risk groups of neurodevelopmental abnormalities. However, it is not clear whether the effects of element exposure in utero on postpartum neurodevelopment are different between full-term infants and preterm infants. Objective To evaluate the effects of element exposure levels during pregnancy on neurodevelopment of children aged 6-24 months (of corrected age), and compare the effects between preterm and full-term children. Methods A prospective study design was adopted and this study was conducted based on the Maoming Birth Cohort Study (MBCS) in Maoming City, Guangdong Province. Twenty elements in cord blood of 197 preterm infants and 297 full-term infants were measured, including 11 essential trace elements [vanadium (V), chromium (Cr), manganese (Mn), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), selenium (Se), strontium (Sr), tin (Sn), and iron (Fe)], and 9 non-essential trace elements [aluminum (Al), arsenic (As), thallium (Tl), lead (Pb), uranium (U), cerium (Ce), antimony (Sb), cadmium (Cd), and yttrium (Y)]. The neurodevelopment of the children at 6, 12, and 24 months were evaluated by the Ages and Stages Questionnaires-the Third Edition (ASQ-3). A generalized estimating equation (GEE) model was adopted to evaluate the associations between elements and neurodevelopment in full-term and preterm children separately. Results The positive rates of 10 elements (Mn, Cu, Zn, Se, Sr, Fe, Sb, Tl, Pb, and As) in cord blood were greater than 80%. Among the preterm birth children, the results of GEE analysis showed that after adjusting for the covariates, for each increase of interquartile range (IQR) in ln-transformed concentration, As was associated with problems/delay in the communication and problem-solving sub-scales, with the adjusted odds ratios (OR) and 95% confidence intervals (CI) of 1.36 (1.03-1.80) and 1.55 (1.10-2.20), respectively; the adjusted OR (95%CI) of problems/delay in the fine motor and problem-solving sub-scales were 1.44 (1.00-2.07) and 1.76 (1.09-2.84) for Sb, respectively; the adjusted OR (95%CI) of problems/delay in the communication sub-scale was 1.37 (1.09-1.74) for Se. No statistically significant associations between umbilical cord blood element concentrations and neurodevelopment indicators were observed among full-term children. The results of stratified analysis by sex showed that the associations between umbilical cord blood element concentrations and neurodevelopment problems/delay were only significant among female preterm children. Conclusion Exposures to As, Se, and Sb during pregnancy may increase the risk of neurodevelopment problems/delay in preterm children aged 6-24 months, and female seem to be more vulnerable.

Ethanol is one of the most widely used and abused psychoactive substances in the world. Long-term and excessive intake of alcohol can damage the central nervous system and lead to impairment of its function. As an important component of the central nervous system, cerebellum is one of the main target organs damaged by ethanol. Acute and chronic ethanol intake can damage human motor coordination, motor learning and some cognitive functions. Its damage mechanism is generally believed to be caused by the abnormal function of cerebellar cortical neural circuit caused by ethanol intake. Combined with recent studies on the mouse model of long-term ethanol intake, this article reviews the cerebellar neural network mechanism of long-term ethanol intake from various aspects, with a view to providing research and development in behavioral movement, motor coordination, cognitive function, depression, and offers new ideas with the rise of precision medicine for treatment. People are increasingly interested in exploring the mechanism of long-term ethanol intake on the cerebellar neural network. How to improve or block the corresponding mechanism based on the mechanism of action found in existing research is an important proposition in future research.

Objective:To investigate the effect of chronic ethanol consumption on sensory information transmission in the cerebellar molecular layer and reveal the mechanism of chronic alcoholism on sensory information transmission and integration in the cerebellar cortex.Methods:Fifty healthy male ICR mice aged 6-8 weeks were randomly divided into saline group(control group)and ethanol consumption group(alcohol group) according to the random number table, with 25 mice in each group.The mice in alcohol group were injected intraperitoneally with 20% ethanol daily, while the mice in control group were injected with the same dose of normal saline. All mice were injected intraperitoneally once a day for 28 days.Through electrophysiological technology, patch-clamp amplifier and data acquisition software were used to record the changes in cerebellar molecular layer field potential of mice in the alcohol group and control group induced by sensory stimulation.Clampfit 10.3 software was used to record and analyze the electrophysiological data. SPSS 22.0 software was used for statistical analysis. Paired t-test and one-way ANOVA were used to analyze the differences before and after treatment. Results:After giving the stimulation of wind blowing, the amplitude of P1 in alcohol group was significantly higher than that in control group ((121.31±3.5)%, (97.2±2.7)%; t=26.08, P<0.05), and the area under the P1 curve (AUC) of the alcohol group was significantly lower than that of the control group ((127.1±4.2)%, (102.2±3.5)%; t=22.95, P<0.05). There was no significant difference in N1 amplitude between the two groups (P>0.05). When L-NNA, an inhibitor of nitric oxide synthase, was perfused into the brain surface of mice, the amplitude of P1 in alcohol group was significantly lower than that before administration ((76.2±4.8)%, (103.5±3.6)%; t=22.60, P<0.05), but there was no difference of the amplitude of P1 before administration and after elution ((101.5±4.6)%) ( t=1.70, P>0.05). After the L-NNA was perfused, the AUC of P1 was significantly lower than that before administration((72.4±5.6)%, (102.7±2.66)% ( t=24. 58, P<0.05), and there was no significant difference between before administration and after elution( (100.6±3.5)%, t=1.81, P>0.05). When L-NNA was perfused into the brain surface of mice, the amplitude of P1 in control group was (104.3±1.6)% and it had no differences compared with before administration(102.2±5.6)%, t=1.84, P>0.05) and after elution(102.5±4.5)%, t=1.92, P>0.05). And the AUC of P1 in control group after perfused L-NNA had no differences compared with before administration(103.5±2.6)%, (102.5±4.6)%) and after elution((101.9±3.7)%, t=0.99, 1.81, both P>0.05). When the mouse brain surface was perfused with NO donor SNAP, the amplitude of P1 in the control group was significantly higher than that before administration( (128.2±3.4)%, (103.5±2.6)%; t=28.89, P<0. 05) and there was no difference between before administration and after elution( (105.4±4.2)% , t=1.93, P>0.05). The AUC of P1((125.4±4.4)%) was higher than before administration((104.3±4.6)% , t=16.60, P<0.05) and there was no difference between before administration and after elution(103.5±4.2)%, t=0.65, P>0.05). Conclusion:Chronic ethanol consumption significantly enhances the inhibitory response, and the enhancement of inhibitory components stems from the activation of the NO signaling pathway.

OBJECTIVE: To explore the effect of occupational lead exposure on the relative telomere length(RTL) and mRNA expression of telomere-binding protein POT1-interacting protein 1(TPP1) in peripheral blood of workers. METHODS: A total of 303 workers exposed to lead were selected as the exposure group and 72 administrative logisticians personnel in the same factory as the control group using the simple random sampling method. Their peripheral blood samples were collected and were used to detect the blood lead level by Graphite furnace atomic absorption spectrometry. RTL and the relative expression of TPP1 mRNA by real-time quantitative polymerase chain reaction. RESULTS: The blood lead level of the exposure group was higher [Media(M): 68.2 vs 266.1 μg/L, P<0.01], the RTL was shorter(M: 0.96 vs 0.70, P<0.01), and the relative mRNA expression of TPP1 was lower(M: 0.92 vs 0.51, P<0.01) compared with the control group. Spearman correlation analysis results showed that the blood lead level were both negatively correlated with RTL [Spearman correlation coefficient(r_S) =-0.18, P<0.01], and the relative mRNA expression of TPP1(r_S=-0.19, P<0.01), while the RTL was positively correlated with the risk of RTL shortening and the relative mRNA expression of TPP1 decline was increased in lead exposure(P<0.01). CONCLUSION: Lead exposure can shorten the RTL and reduce the relative mRNA expression of TPP1 in workers. The mechanism may be that lead interferes with telomere repair process by inhibiting the mRNA expression of TPP1.

Objective: To exploring the relationship between college students’ mobile phone addiction, social support and depression. Methods: During May 2019, 1 703 students from five universities in Shandong Province were selected to complete a questionnaire composed of Mobile Phone Addiction Tendency Scale(MPATS), Perceived Social Support Scale(PSSS) and Center for Epidemiological Studies Depression Scale(CES-D). Results: The scores of mobile phone addiction, social support and depression among college students were(32.84±9.30)(67.20±11.09)(11.61±8.65). The mobile phone addiction and depression score of the low social support group were significantly higher than those of the high social support group( t =10.01, 15.89, P <0.01). Regression analysis showed that mobile phone addiction in the high social support group explained the depression variation to lower than the low social support group( R 2=0.16, 0.19, P <0.01). Social support had a partial mediating effect on mobile phone addiction and depression. The median effect value was -0.10, accounting for 21.0% of the total effect. Conclusion College students’ social support has partial mediating effects on the influence of mobile phone addiction on their depression. Improving the social support level of college students is advantageous to reduce the negative impact of mobile phone addiction on their depressive symptoms.