1.Application of PET-based neuroimaging ATN framework in the diagnosis of Alzheimer′s disease
Min XIONG ; Hongji YOU ; Xiaoming LUO ; Yipei LIU ; Shengnan JIANG
Chinese Journal of Nuclear Medicine and Molecular Imaging 2024;44(12):705-711
Objective:To explore the value of the amyloid-tau-neurodegeneration (ATN) framework in neuroimaging based on PET for diagnosing mild cognitive impairment (MCI) and Alzheimer′s disease (AD), and analyze its relationship with clinical cognition.Methods:From May 2022 to March 2024, a total of 98 cases (23 males and 75 females, age (67.8±8.6) years) with a diagnosis of AD, MCI, or non-AD (control patients, CP) who underwent 18F-FDG, 18F-AV45, and 18F-AV1451 PET/CT imaging in the Second Affiliated Hospital of Guangzhou Medical University were included retrospectively. The clinical data, Mini-Mental State Examination (MMSE), and Montreal Cognitive Assessment (MoCA) scores were recorded. Cases were divided into MCI group, mild AD group, moderate AD group, moderate-severe AD group, and CP group. PET images were visually and semi-quantitatively evaluated. SUV mean and SUV ratio (SUVR) were obtained from independent brain regions of 18F-FDG ( n=8), 18F-AV45 ( n=14) and 18F-AV1451 ( n=14). ROC curve analysis was performed with clinical diagnosis as a criterion. The consistency between visual assessment and the clinical diagnosis was analyzed by Cohen′s Kappa coefficient. Semi-quantitative comparisons between groups were performed using the independent-sample t test, one-way analysis of variance, Mann-Whitney U test, or Kruskal-Wallis rank sum test. Age was used as a covariate to calculate the partial correlation coefficient between SUVR and cognitive scores. Results:The sensitivity and specificity of comprehensive visual assessment in diagnosing AD+ MCI were 87.65%(71/81) and 14/17 respectively, showing a moderate consistency with clinical diagnosis ( Kappa=0.60, P<0.001). Semi-quantitative analysis showed that 18F-FDG uptakes in all independent brain regions of MCI patients were higher than those of AD patients, whereas the uptakes of 18F-AV45 and 18F-AV1451 were lower ( t values: 2.66-3.95, z values: 4.98-15.04, all P<0.05). The difference in 18F-AV45 uptake among the three subgroups of AD was relatively small ( H values: 0.46-4.06, F values: 0.03-0.08, all P>0.05). Except for the medial temporal and occipital lobes, the 18F-AV1451 uptake in the moderate-severe AD group tended to be higher than that in the moderate and mild AD groups, though not statistically significant ( H values: 0.20-5.17, all P>0.05). 18F-FDG PET semi-quantitatively distinguished MCI from CP with a high sensitivity (13/14), 18F-AV45 demonstrated a high sensitivity for diagnosing AD+ MCI (92.59%, 75/81), and 18F-AV1451 had a high specificity for distinguishing AD from MCI (14/14) (AUCs: 0.87, 0.90 and 0.92). The uptakes of 18F-FDG in gray matter of AD and MCI patients were positively correlated with MMSE and MoCA scores ( r values: 0.30-0.43, 0.29-0.45, all P<0.05), while the uptakes of 18F-AV45 and 18F-AV1451 were negatively correlated with MMSE and MoCA scores ( 18F-AV45, r values: from -0.39 to -0.30, from -0.38 to -0.30, all P<0.05; 18F-AV1451, r values: from -0.50 to -0.28, from -0.53 to -0.28, except for medial temporal lobe P>0.05, all others P<0.05). Conclusion:The PET-based neuroimaging ATN framework is helpful for early diagnosis of MCI and AD, as well as for AD staging, and may reflect the disease progression and clinical cognitive status of AD to a certain extent.
2.Construction of EIF4A3 shRNA lentiviral vector and establishment of its stable transfection cell line
Jiawen HE ; You LI ; Keqi LIAO ; Shengnan LI
Journal of Jilin University(Medicine Edition) 2024;50(3):831-839
Objective:To construct the eukaryotic cell translation initiation factor 4A3(EIF4A3)short hairpin RNA(shRNA)lentiviral vector,and to establish the Neuro-2a-EIF4A3-shRNA stable transfection cell line.Methods:The EIF4A3 gene sequence was retrieved from the National Center for Biotechnology Information(NCBI)database;the PCR identification primers were designed and synthesized,and connected to the lentiviral GV493 vector digested with Eco R I and Age I enzymes to construct the GV493-EIF4A3-shRNA lentiviral plasmid;PCR method was used to screen the positive clones,which were sequenced for the identification;the GV493 empty plasmid and GV493-EIF4A3-shRNA recombinant plasmid were transfected into the HEK293T cells,regarded as GV493 control lentivirus and GV493-EIF4A3-shRNA lentivirus,respectively.After 48 h of transfection,the lentiviruses were collected for packaging and the viral titer was determined.The Neuro-2a cells were divided into blank group,GV493 control group,and GV493-EIF4A3 shRNA group.The Neuro-2a cells in blank group were untreated,and the Neuro-2a cells in GV493 control group and GV493-EIF4A3 shRNA group were infected with the respective lentiviruses at a multiplicity of infection(MOI)of 100.The infected Neuro-2a cells were selected by 10 mg·L-1 puromycin,and the growth status and green fluorescence expression of the Neuro-2a cells in various groups were observed under fluorescence microscope;real-time fluorescence quantitative PCR(RT-qPCR)and Western blotting methods were used to detect the expression levels of EIF4A3 mRNA and protein in the Neuro-2a cells in various groups.Results:The PCR sequencing results showed that the gene sequence of the GV493-EIF4A3-shRNA recombinant plasmid was consistent with the designed EIF4A3-shRNA sequence,indicating successful construction of the GV493-EIF4A3 lentiviral vector.The fluorescence microscope observation results showed that there was strong fluorescence expression and good growth status in the HEK293T cells,confirming successful lentiviral packaging.The viral titers for GV493 control lentivirus and GV493-EIF4A3-shRNA lentivirus both were 2×108 TU·mL-1.The growth status of the Neuro-2a cells in GV493 control group and GV493-EIF4A3 shRNA group was good,and they expressed green fluorescence,indicating successful construction of the stable transfection cell line.The RT-qPCR results showed that compared with blank group and GV493 control group,the expression level of EIF4A3 mRNA in the cells in GV493-EIF4A3 shRNA group was significantly decreased(P<0.01).The Western blotting results showed that the specific bands was at a relative molecular mass of 49 000,indicating successful EIF4A3 protein expression in the Neuro-2a cells.Compared with blank group and GV493 control group,the expression level of EIF4A3 protein in the cells in GV493-EIF4A3 shRNA group was significantly decreased(P<0.01).Conclusion:The GV493-EIF4A3-shRNA lentiviral vector is succfssfully constructed,and the Neuro-2a-EIF4A3-shRNA stable transfection cell line is established;the results provide the reference for the study of the effect of EIF4A3 on the intracranial atherosclerosis.
3.Construction of dedicator of cytokinesis 4 over-expressed lentivirus vector and establishment of stable transfected Neuro-2a cells
Shengnan LI ; Jiawen HE ; Keqi LIAO ; You LI
Journal of Jilin University(Medicine Edition) 2024;50(5):1322-1329
Objective:To construct an over-expression lentiviral vector of the dedicator of cytokinesis 4(DOCK4),and to establish DOCK4 stably over-expressing Neuro-2a cells.Methods:The DOCK4 sequence was searched in the National Center for Biotechnology Information(NCBI)and primers were designed and synthesized;polymerase chain reaction(PCR)method was used to amplify the DOCK4 gene sequences.After digestion with BamH Ⅰ and Age Ⅰ restriction endonucleases,the DOCK4 gene sequences were ligated with the digested lentiviral vector GV492 to construct the GV492-DOCK4 over-expression recombinant plasmid.The positive clones with a similar length to the target gene fragment were screened and identified by PCR method.The GV492-control plasmid and GV492-DOCK4 over-expression recombinant plasmid were transfected into the HEK293T cells,and the lentivirus was collected and titered 48 h after transfection.The Neuro-2a cells were divided into GV492-control group and GV492-DOCK4 group,and the cells were infected with GV492-control lentivirus and GV492-DOCK4 over-expression lentivirus,respectively,and the multiplicity of infection(MOI)was 100.After 72 h of infection,the successfully infected Neuro-2a cells were screened by using puromycin(10 mg·L-1).The growth status of Neuro-2a cells and the expression of green fluorescent protein in various groups were observed under fluorescence microscope.Real-time quantitative PCR(RT-qPCR)and Western blotting methods were used to detect the expression levels of DOCK4 mRNA and DOCK4 protein in the Neuro-2a cells in various groups.Results:The PCR results showed that the gene fragment length of the GV492-DOCK4 over-expression recombinant plasmid was approximately 691 bp.The sequencing results showed that the gene sequence of the GV492-DOCK4 over-expression recombinant plasmid was consistent with the designed over-expression sequence of DOCK4.The titers of the lentiviruses in GV492-control group and GV492-DOCK4 over-expression group were 2.5×108 TU·mL-1 and 2.5×108 TU·mL-1,respectively.The fluorescence microscope observation results showed that Neuro-2a cells in various groups grew well and expressed green fluorescent protein.The RT-qPCR results showed that compared with GV492-control group,the expression level of DOCK4 mRNA in the Neuro-2a cells in GV492-DOCK4 group was significantly increased(P<0.01).The Western blotting results showed the specific bands near the relative molecular mass of 225 000 in various groups.Compared with GV492-control group,the expression level of DOCK4 protein in the Neuro-2a cells in GV492-DOCK4 group was significantly increased(P<0.01).Conclusion:This study successfully constructs the DOCK4 over-expression lentiviral vector and establishes the Neuro-2a cells stably over-expressing DOCK4.
4.Phase amplitude coupling analysis of local field potentials in working memory of rats affected by transcranial magneto-acoustic-electrical stimulation.
Junwu DANG ; Shuai ZHANG ; Shengnan YOU ; Wenjing DU ; Guizhi XU
Journal of Biomedical Engineering 2022;39(2):267-275
Transcranial magneto-acoustic-electrical stimulation is a new non-invasive neuromodulation technology, in which the induced electric field generated by the coupling effect of ultrasound and static magnetic field are used to regulate the neural rhythm oscillation activity in the corresponding brain region. The purpose of this paper is to investigate the effects of transcranial magneto-acoustic-electrical stimulation on the information transfer and communication in neuronal clusters during memory. In the experiment, twenty healthy adult Wistar rats were randomly divided into a control group (five rats) and stimulation groups (fifteen rats). Transcranial magneto-acoustic-electrical stimulation of 0.05~0.15 T and 2.66~13.33 W/cm 2 was applied to the rats in stimulation groups, and no stimulation was applied to the rats in the control group. The local field potentials signals in the prefrontal cortex of rats during the T-maze working memory tasks were acquired. Then the coupling differences between delta rhythm phase, theta rhythm phase and gamma rhythm amplitude of rats in different parameter stimulation groups and control group were compared. The experimental results showed that the coupling intensity of delta and gamma rhythm in stimulation groups was significantly lower than that in the control group ( P<0.05), while the coupling intensity of theta and gamma rhythm was significantly higher than that in the control group ( P<0.05). With the increase of stimulation parameters, the degree of coupling between delta and gamma rhythm showed a decreasing trend, while the degree of coupling between theta and gamma rhythm tended to increase. The preliminary results of this paper indicated that transcranial magneto-acoustic-electrical stimulation inhibited delta rhythmic neuronal activity and enhanced the oscillation of theta and gamma rhythm in the prefrontal cortex, thus promoted the exchange and transmission of information between neuronal clusters in different spatial scales. This lays the foundation for further exploring the mechanism of transcranial magneto-acoustic-electrical stimulation in regulating brain memory function.
Acoustics
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Animals
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Electric Stimulation
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Memory, Short-Term/physiology*
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Rats
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Rats, Wistar
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Theta Rhythm/physiology*
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Transcranial Direct Current Stimulation
5.The coverage of work injury insurance and its affecting factors in Zhejiang province, China.
Shengnan DUAN ; Hengjin DONG ; Yuan WU ; Chiyu YE ; Xiaofang LIU ; Hua YOU ; Huimei HU ; Linhao WANG ; Xing ZHANG ; Jing WANG
Chinese Journal of Industrial Hygiene and Occupational Diseases 2014;32(12):892-897
OBJECTIVEIn China, the coverage rate of work injury insurance was 23.2%in 2011, which was far lower than expected. The factors affecting the insurance's enrollment has very little known. This paper aims to study the existing coverage of work injury insurance scheme and its influencing factors.
METHODSThe data were collected from 2 836 workers who came from 9 industries in three cities of Zhejiang province using face-to-face questionnaire interview.
RESULTSOf these 2836 workers, the work injury insurance coverage was 50.1%, and 29.6% were not sure if they were covered or not. The results showed that the awareness of occupational disease and industrial injury insurance was helpful in increasing the coverage rate. Besides, the logistic regression analysis showed that in certain circumstances working population shared higher coverage of work injury insurance. For examples, male workers with local household registration and longer working years; people who had been informed about occupational risk factors, and thus gained more training on the issue; people who had exposed to occupational hazards or involved in administrative duties; and people who had already insured by a medical insurance scheme. In the contrary, the heavier family burden with longer working hours per week they needed, the lower possibility they joined the insurance scheme.
CONCLUSIONSThe coverage of work injury insurance is higher than native average level but much lower than the average international level. The awareness of occupational disease and injury insurance was closely associated with the coverage of work injury insurance. Therefore, it is imperative to popularize the knowledge on OHS for migrant workers, as well as to reinforce the supervision and management of the issue would have been an effective way to elevate the coverage rate of work injury insurance.
China ; Cities ; Health Services Needs and Demand ; Humans ; Insurance Coverage ; statistics & numerical data ; Male ; Occupational Diseases ; Surveys and Questionnaires ; Transients and Migrants
6.Effects of transcranial magneto-acoustical stimulation on beta oscillations in neural circuits of healthy and Parkinson's disease rats
Shuai ZHANG ; Shengnan YOU ; Wenjing DU ; Lei WANG ; Guizhi XU
Chinese Journal of Tissue Engineering Research 2024;28(16):2519-2526
BACKGROUND:Transcranial magneto-acoustical electrical stimulation(TMAES)is a non-invasive,high-precision neurofocused stimulation method based on magneto-acoustic coupling electrical effect,which can regulate the rhythmic oscillation of nerve activity,thereby affecting the brain's movement,cognition and other functions. OBJECTIVE:To explore the effect of TMAES on beta oscillations in the neural circuits of healthy rats and Parkinson's rats. METHODS:(1)Animal experiments:Twenty-four Wistar rats were randomly divided into four groups(n=6 per group).The rats in the normal control group received no intervention,while those in the normal stimulation group received TMAES(the average spatial peak pulse intensity:13.33 W/cm2,fundamental frequency:0.4 MHz,the number of fundamental wave cycles:1000,and pulse frequency:200 Hz).The model control group and model stimulation group were established by intraperitoneal injection of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine.After successful modeling,the rats in the model control group received sham TMAES stimulation in the prefrontal cortex,and those in the model stimulation group received TMAES in the prefrontal cortex,and the duration of stimulation was 2.0 minutes per day.After an interval of 8-10 minutes,the local field potential signals of rats were collected during the execution of T-maze test and the correct rate of behavior was recorded at the same time to compare and analyze the time-frequency distribution of local field potential signals and behavioral differences among the groups.The stimulation experiment and T-maze test were stopped when the correct rate of rats was higher than 80%for 3 consecutive days.(2)Modeling and simulation experiments:The cortical-basal ganglion circuit model under TMAES was established,and the ultrasonic emission period(5,10,20 ms),ultrasonic emission duty cycle(30%,50%,90%)and induced current density(20,50,100 μA/cm2)were changed respectively to compare the power spectral density values of beta oscillations in healthy rats and Parkinson's rats under different stimulation parameters. RESULTS AND CONCLUSION:(1)Animal experiments:The spatial learning ability of the rats in the normal control group was stronger than that of the model control group(P<0.001),the spatial learning ability of the rats in the normal stimulation group was stronger than that of the normal control group(P<0.05),and the spatial learning ability of the rats in the model stimulation group was stronger than that of the model control group(P<0.01).The distribution of beta oscillation energy in the normal control group was more concentrated,and the beta oscillation signal energy was reduced in the normal stimulation group compared with the normal control group.The beta oscillation energy was widely distributed and the energy value was significantly higher in the model control group and the model stimulation group than the normal control and normal stimulation groups.Moreover,the beta oscillation signal energy in the model stimulation group was significantly lower than that in the model control group.(2)Modeling and simulation experiments:the peak power spectral density of the beta band of healthy rats without stimulation(30 dB)was significantly lower than that of Parkinson's rats(55 dB).The power spectral density value generally decreased after stimulation.The peak power spectral density in the beta band was positively correlated with the ultrasonic emission period and negatively correlated with the induced current density.In addition,the peak power spectral density value was the lowest when the duty cycle of ultrasonic emission was 50%.These findings indicate that TMAES suppresses beta oscillations in healthy and Parkinson's disease rats,thereby improving motor function and decision-making cognitive function in rats.
7.Study on willingness to participate and willingness to pay for hypothetical industrial injury insurance scheme.
Yuan WU ; Hengjin DONG ; Shengnan DUAN ; Xiaofang LIU ; Chiyu YE ; Hua YOU ; Huimei HU ; Linhao WANG ; Xing ZHANG ; Jing WANG
Chinese Journal of Industrial Hygiene and Occupational Diseases 2014;32(10):732-741
OBJECTIVETo investigate workers' willingness to participate and wiliness to pay for a hypothetical industrial injury insurance scheme, to analyze the influential factors, and to provide information for policy making of the government.
METHODSMultistage cluster sampling was used to select subjects: In the first stage, 9 small, medium, orlarge enterprises were selected fromthree cities (counties) in Zhejiang province, China, according to the level of economic development, transportation convenience, and cooperation of government agencies; in the second stage, several workshops were randomly selected from each of the 9 enterprises. Face-to-face interviews among all workers in the workshops were conducted by trained interviewers using a pre-designed questionnaire.
RESULTSIt was found that 73.87% (2095) of all workers were willing to participate in the hypothetical work injury insurance scheme and to pay 2.21% of monthly wage (51.77 yuan) on average, and more than half of the workers were willing to pay less than 1%of monthly wage (35 yuan). Of the 741 workers who were not willing to participate, 327 thought that the premium should be borne by the state or enterprises, instead of individuals, and others were not willing to participate because of low income, unstable job, or poor understanding of the hypothetical industrial injury insurance scheme. Logistic regression analysis showed that workers with higher education levels, longer length of services, longer weekly working time, or more knowledge of occupational diseases showed higher willingness to participate in the scheme; workers who were exposed to physical hazards, had health records, or had participated in the existing medical insurance or industrial injury insurance were more willing to participate. Multiple linear regression analysis showed that with increasing average monthly wage, weekly working time, and self?health evaluation, the proportion of workers with willingness to pay increased; however, with increasing work intensity and awareness of occupational disease, the proportion of workers with willingness to pay decreased. The workers who were not covered by the industrial injury insurance paid more than those covered by the industrial injury insurance.
CONCLUSIONThe hypothetical industrial injury insurance scheme increased the applicability and advantage of independent third-party running and lifetime insurance, which significantly increased the workers' willingness to participate in or to pay for the insurance scheme. Therefore, the industrial injury insurance can be improved in these aspects to promote workers' willingness to participate in and to pay for the insurance scheme. This conclusion provided a reference for the solution of delayed or shirking corporate responsibility for paying the premium.
Accidents, Occupational ; economics ; Attitude to Health ; China ; Cluster Analysis ; Financing, Personal ; Health Policy ; Humans ; Insurance ; Insurance, Health ; economics ; utilization ; Models, Theoretical ; Occupational Diseases ; economics ; Surveys and Questionnaires