1.The Neural Circuit Characteristics of Repetitive Transcranial Magnetic Stimulation Over The Dorsolateral Prefrontal Cortex for The Treatment of Migraine
Chen-Xia JIN ; Bo-Lin TAN ; Yang YE ; Ji-Qing HE ; Ling-Yan WANG ; Zhong-Ming GAO ; Yu-Jun WANG ; Hui-Li LIU ; Yong-Xing YAN ; Xian-Wei CHE
Progress in Biochemistry and Biophysics 2026;53(7):1953-1968
ObjectiveMigraine is a leading neurological disorder and the fourth most common cause of years lived with disability worldwide, affecting nearly 116 million individuals. Although pharmacological treatments are available, their efficacy is often limited by side effects and variable response rates. Repetitive transcranial magnetic stimulation (rTMS) over the dorsolateral prefrontal cortex (DLPFC) offers a safe, non-invasive alternative for migraine management. However, the neurophysiological mechanisms, particularly how rTMS modulates local cortical excitability and distributed pain-related circuits, remain poorly understood. Elucidating these mechanisms is essential for optimizing treatment protocols and improving clinical outcomes. MethodsThis study employed concurrent transcranial magnetic stimulation and electroencephalography (TMS-EEG) to investigate neuroplastic and neurocircuitry mechanisms of DLPFC-rTMS in migraine. Study 1 compared 30 migraineurs and 28 healthy controls to identify abnormalities in TMS-evoked potentials (TEPs) and significant current density (SCD) within sensory-discriminative regions including the primary somatosensory cortex (S1) and posterior insula (pINS), cognitive-affective regions including the anterior insula (aINS) and midcingulate cortex (MCC), and a descending modulatory region, the periaqueductal gray (PAG). Study 2 used a single-blind, crossover, sham-controlled design in 34 healthy participants. Each participant received both active (10 Hz, 80% RMT, 1 500 pulses) and sham DLPFC-rTMS in counterbalanced order. TMS-EEG and cold pain tolerance were assessed before and after each session. ResultsIn Study 1, migraineurs showed a significantly less negative N120 amplitude compared to healthy controls (P=0.027, Cohen’s d=0.60), indicating local intracortical disinhibition. No group differences were observed for N40, P60, or P180 components. At the source level, migraineurs exhibited significantly higher SCD in the S1, pINS, aINS, and MCC (allQ<0.05), but not in the ventroposterior thalamus (vpTHAL), mediodorsal thalamus (mdTHAL), or PAG. In Study 2, active rTMS significantly reduced SCD from pre- to post-stimulation in the S1, aINS, and MCC (all Q<0.05). Sham stimulation also reduced SCD in the S1 (Q<0.05) but not in the aINS or MCC. Although no significant group-level analgesic effect was observed between active and sham conditions (P=0.107), correlation analyses revealed that greater SCD reductions in the S1 and MCC were significantly associated with higher post-rTMS pain tolerance (R=-0.487 and -0.495, both Q<0.01) and larger improvements in pain tolerance(R=-0.487 and -0.451, both Q<0.05). No such correlations were found following sham stimulation, suggesting that the behavioural relevance of neural changes is specific to active rTMS. ConclusionThis study provides novel evidence that migraineurs exhibit both local neuroplastic abnormalities (reduced N120 amplitude) and hyperactivity in key pain-processing regions (S1, pINS, aINS, MCC). A single session of DLPFC-rTMS reduced hyperactivity in the aINS, MCC, and S1. Notably, greater reductions in the S1 and MCC were associated with improved pain tolerance. These findings identify distinct cortical circuitries, particularly within the cognitive-affective pain network, that may serve as potential biomarkers for optimizing rTMS treatment in migraine and other chronic pain conditions. Future studies should validate these results in patient populations experiencing spontaneous migraine attacks and explore multi-session or accelerated rTMS protocols.
2.Quantitative analysis of motion of cardiac substructures in deep inspiratory breath holding radiotherapy for left breast cancer
Zhao-hui TANG ; Zhe ZHANG ; Wei-bin MAO ; Bo HUANG ; Jun-feng AI ; Chao-fan ZHU ; Zhi-chao XIE ; Ya-jie LIU
Chinese Medical Equipment Journal 2025;46(3):54-58
Objective To quantify the volume and movement of cardiac substructures by using coronary computed tomography angiography(CCTA)to provide guidance for the design of deep inspiratory breath-holding radiation therapy for left breast cancer and the protection of organs at risk.Methods Totally 18 female patients who received conventional chest plain scan and CCTA were selected to simulate the design process of radiotherapy plan for left breast cancer patients with internal mammary lymph nodes.Retrospective reconstruction of CCTA data was performed for each patient,with 10 phase images(with an interval of 10%)within a R-R cardiac cycle(10%-100%)to simulate the true range of motion of the heart.The heart,left atrium(LA),left ventricle(LV),right atrium(RA),right ventricle(RV),left anterior descending artery(LAD),left circumflex coronary artery(LCX)and right coronary artery(RCA)were contoured at each phase.The distances from the centroid position to the average position of LAD,LCX and RCA were measured at each phase in the superior-inferior(SI),anterior-posterior(AP)and left-right(LR).The average volume and range of volume changes of LA,LV,RA,RV and heart were analyzed within a cardiac cycle.The expansion margins of planning organs at risk volume(PRV)were calculated.SPSS 19.0 software was used for statistical analysis.Results The following average absolute displacements were found in SI,AP and LR coordinates:(1.8±0.7)mm,(1.2±0.5)mm and(1.5±0.5)mm for LAD,respectively;(2.1±0.7)mm,(1.5±0.6)mm and(1.9±0.7)mm for LCX,respectively;(1.6±0.5)mm,(2.2±0.9)mm and(2.2±0.8)mm for RCA,respectively.The volume changes of LA,LV,RA,RV and heart within a cardiac cycle ranged from 34.3 to 63.9 cm3,122.1 to 154.3 cm3,29.3 to 53.6 cm3,57.2 to 94.3 cm3 and 480.1 to 515.4 cm3,respectively.The theoretical expansion margins of LAD,LCX and RCA in all the three directions were within 2 mm.Conclusion The ranges of movement and volume changes of cardiac substructure are quantitati-vely displayed,and references are provided for the planning of deep inspiratory breath-holding radiation therapy for left breast cancer and the protection of organs at risk.[Chinese Medical Equipment Journal,2025,46(3):54-58]
3.Effects of glycerol ingestion on pure tone audiometry,distortion products otoacoustic emission,and electrocochleography in patients with Ménière disease
Hui PAN ; Linlin WANG ; Cheng LUO ; Meng GONG ; Mengjun WU ; Yi SHU ; Wen XIE ; Hongjun XIAO ; Bo LIU
Journal of Audiology and Speech Pathology 2025;33(4):372-376
Objective To investigate the effects of glycerol ingestion on pure tone audiometry(PTA),distor-tion products otoacoustic emission(DPOAE),and electrocochleography(ECochG)in patients with Ménière disease(MD).Methods Glycerol test was conducted in 50 patients with MD.PTA was performed in four series:before glycerol intake,1,2 and 3 hours after intake.DPOAE and ECochG were performed before glycerol intake and 2 hours after intake.All results were analyzed to assess the effect of glycerol on cochlear function of patients with MD.Results ① 55%of MD patients tested positive in PTA glycerol test,and the positive rate increased gradually after 1-3 hours of glycerin ingestion(P<0.05).For the 33 positive ears,the pure tone threshold decreased the most between 1-2 hours and reached the lowest thresholds at 3 hours.Thresholds at 0.5 kHz,1 kHz,2 kHz dropped the most.② The positive rate of DPOAE glycerol test was 56.67%,with 34 positive ears showing a sig-nificant increase in amplitude between 0.75-2 kHz of f2.③ The positive rate of ECochG glycerin test was 13.64%.The decrease of-SP/AP ratio was not statistically significant before and after ingestion of glycerin(P>0.05).Conclusion Ingestion of glycerin could alter to varying degrees of the results of PTA,DPOAE and ECo-chG,and influence the cochlear function to some extent.
4.A qualitative study of self-harm and suicidal behavior in male prisoners
Jiali YANG ; Lan WANG ; Weiyi LIU ; Chao WANG ; Bo YANG ; Hui ZHAO
Chinese Mental Health Journal 2025;39(6):534-540
Objective:To explore the occurrence,co-occurrence,and different subtypes of self-harm and sui-cidal behaviors among male prisoners to inform the development of targeted intervention strategies.Methods:A phenomenology in qualitative research was adopted,and 30 male prisoners with a history of self-harm behaviors,suicidal ideation and suicideattempts,were selected for semi-structured interviews.Data was analyzed by Colaizzi's seven-step method to distill themes.Results:Theme analysis revealed 4 themes and 9 sub-themes(subtypes)of the self-harm and suicidal behaviors of male prisoners,namely the initial occurrence of self-harm behaviors,non-suicid-al self-injury(NSSI)including 6 subtypes(emotional management disorder,self-punishing,antagonistic dissocia-tion,sensation seeking,self-harm without self-awareness,and instrumental self-harm),the co-occurrence of self-harm-suicide behaviors with a subtype of rational suicide,the acute suicide behavior including two subtypes(impul-sive suicide and psychiatric suicide).Conclusion:Negative emotions and emotional dysregulation are important re-lated factorsof self-harm among male prisoners.Suicidal behaviors commonly co-occurred with NSSI,and under-standing the NSSI of prisoners could provide reference for suicide prevention in prisons.There is variability in the motivation of different subtypes of NSSI in maleprisoners,and subtype-based personalized interventions could be a-dopted to reduce the occurrence of self-harm and suicidal behaviors.
5.Resected bone surface anatomy measurement in KBD population for total knee arthroplasty based on three-dimensional computed tomography
Bo YANG ; Ming CHEN ; Shizhang LIU ; Yanhai CHANG ; Hui QIANG ; Ming LING ; Jian TAO ; Pengzhen LEI
Journal of Xi'an Jiaotong University(Medical Sciences) 2025;46(4):650-655
Objective To measure and analyze anatomic parameters of resected distal femurs and proximal tibias in Kaschin-Beck disease(KBD)and osteoarthritic(OA)knees which fit for total knee arthroplasty(TKA),so as to provide basis for designing suitable knee prosthesis for KBD patients.Methods A total of 154 knees(75 KBD and 79 OA)fitting for TKA underwent three-dimensional reconstruction;resection of distal femurs and proximal tibias was simulated during TKA.We measured the distal femoral mediolateral(fML),lateral anteroposterior(fLAP),medial anteroposterior(fMAP),medial condylar width(fMCW),lateral condylar width(fLCW)and fML/fLAP aspect ratio,proximal tibial mediolateral(tML),middle anteroposterior(tAP),medial anteroposterior(tMAP),lateral anteroposterior(tLAP)dimension,and tML/tAP aspect ratio to compare the morphometric differences between KBD and OA knees.Results The measured anatomic parameters of resected distal femurs and proximal tibias in both male and female patients of KBD group were smaller than those of OA knees(P<0.01).We also found that KBD group had larger distal femur fML/fLAP and proximal tibia tML/tAP aspect ratios than those of OA knees(P<0.01).This indicated that under a given AP dimension,KBD knees need an oval-shaped prosthesis with a wider ML length and more spherical-shaped prosthesis with relatively narrow ML dimensions in OA knees.Conclusion The anatomy of distal femurs and proximal tibias shows significant differences in size and shape between KBD and OA knees,which provides theoretical basis for designing proper knee prosthesis for KBD patients.
6.The improvement effect and influencing factors of microsurgical varicocelectomy on scrotal pain
Kan CHEN ; Chun-hui YAN ; Bo LIU ; Jian SHI ; Fang LI
Journal of Regional Anatomy and Operative Surgery 2025;34(8):693-697
Objective To investigate the improvement effect of microsurgical varicocelectomy with vein ligation on scrotal pain and the related factors affecting the improvement of postoperative pain.Methods A retrospective analysis was conducted on the clinical data of 110 patients who underwent microsurgical inguinal varicocelectomy in Central Theater Command General Hospital from November 2021 to June 2023.The degree of pain before and after the operation was evaluated by Numerical Rating Scale(NRS).The pain relief rate,the occurrence of postoperative complications and the overall satisfaction of patients were evaluated.The semen and hormone levels of the patients before and after the operation were analyzed.Univariate and multivariate linear regression analyses were performed to investigate the relationship between clinical variables and postoperative 7-day NRS score.Results The average number of ligated veins during the operation was(6.60±3.76);postoperative satisfaction of patients was(4.23±1.08)points;complications occurred in 7 patients after the operation;after 3 months of follow-up,the overall pain relief rate was 92.73%(102/110).Compared with those before the operation,the NRS score of the patients significantly decreased 7 days after the operation,and the levels of total sperm motility,prolactin and testosterone increased 3 months after the operation,while the levels of serum follicle-stimulating hormone(FSH)and luteinizing hormone(LH)decreased,the differences were statistically significant(P<0.05).The univariate and multivariate linear regression analyses showed that the Dubin-Amelar classification of varicocele(P=0.045),operation time(P=0.049),and number of ligated veins(P=0.024)were significantly correlated with the change of postoperative 7-day NRS score.Patients with 1 to 4,5 to 10,and>10 intraoperative ligation veins were analyzed,and pain relief rates 3 months after the operation were 77.78%(28/36),100%(58/58),and 100%(16/16),respectively,with statistically significant difference(χ2=17.732,P<0.001).Conclusion Microsurgical varicocelectomy can effectively relieve scrotal pain and improve semen quality.Moreover,the relief of postoperative pain is related to the Dubin-Amelar classification of varicocele,the sufficient number of ligated spermatic veins,and the surgical experience of the surgeon.
7.Distalfemur rotational alignment in knee osteoarthritis patients by three-dimensional computed tomography
Bo YANG ; Xianghui HUANG ; Xianghui DONG ; Hui QIANG ; Shizhang LIU ; Pengzhen LEI ; Ming CHEN
Journal of Xi'an Jiaotong University(Medical Sciences) 2025;46(6):991-995
Objective To explore the gender differences and the influence of varus and valgus deformities on distal femur rotational alignment in patients with knee osteoarthritis so as to provide reference for the distal femur rotational osteotomy in total knee arthroplasty(TKA).Methods CT data of 125 knees with osteoarthritis suitable for TKA(including 56 males and 69 females;78 varus knees and 47 valgus knees)were collected and received three-dimensional imaging reconstruction with Mimics software.We measured the posterior condylar angle(PCA),the angle between the anteroposterior axis and the surgical epicondylar axis(ASA),and the angle between the anteroposterior axis and the posterior condylar axis(APA).We also compared gender differences and the influences of varus-valgus deformities on distal femur rotational alignments.Results The PCA and ASA values of distal femur rotational alignments were(3.5±1.1)° vs.(2.8±1.2)°(P=0.001)and(90.6±3.4)° vs.(91.9±3.5)°(P=0.028)for males and females,with statistically differences between the genders.There was no statistically difference in APA between males and females(P=0.482).The PCA values of distal femur rotational alignment in varus and valgus knees were(3.6±1.1)° and(2.9±1.2)°,with a statistically difference between the two groups(P=0.001).There were no statistically differences in ASA or APA between varus and valgus knees(P>0.05).Conclusion Gender and varus-valgus deformities of knee joint affect the distal femur rotational alignment.Distal femur rotational osteotomy angle should be determined according to the patient's CT imaging before TKA to reduce the errors caused by individual differences and improve the accuracy of the distal femur rotational alignment during TKA.
8.Effect of a novel cryoprotectant in tissues and cells
Qingfang WANG ; Fen ZHANG ; Guangping CHANG ; Zihan LI ; Lan XING ; Hao PENG ; Xiuping ZENG ; Guiqiang ZHONG ; Hui CHEN ; Bo LIU ; Zhenyu LIU ; Xiao LIANG
Chinese Journal of Tissue Engineering Research 2025;29(36):7816-7826
BACKGROUND:The cryopreservation technology enables tissues/cells to be stored for a long time in a low-temperature environment while maintaining the integrity of their activity and function,which is of great significance for the construction of cell therapy,tissue engineering and biological sample banks.Cryoprotective agents often contain dimethyl sulfoxide and serum.To avoid the toxic side effects of dimethyl sulfoxide,the complexity of serum components and immune responses,although some finished cryoprotective agents have been marketed,they are faced with many difficulties such as high cost and limited application.Therefore,there is an urgent need to develop a cryoprotective agent with clear components and the ability to solve the above problems.OBJECTIVE:To evaluate the effects of a novel cryoprotectant on cryopreservation efficiency of different tissue and cell sources.METHODS:By applying the novel cryoprotectant as an experimental group with the commercially available and widely used cryoprotectant(control group)to umbilical cord Wharton's jelly tissue,umbilical cord mesenchymal stem cells,umbilical cord blood/peripheral blood mononuclear cells,NK and CIK cells,comparative analyses were conducted in terms of cell morphology,number,viability,surface markers,differentiation potential,and cell-killing toxicity assay before cryopreservation and after resuscitation thawing.We confirmed the cryopreservation effect of the new cryoprotectant and its potential application value.RESULTS AND CONCLUSION:(1)The novel cryoprotectant facilitated the normal growth of cryopreserved Wharton's jelly tissue upon recovery,exhibiting mesenchymal stem cell morphology.No significant differences were observed between the experimental and control groups in terms of cell recovery rate,surface markers,and differentiation potential.(2)There was no significant difference in the number and viability of cells between the experimental group and the control group after cryopreservation of cord blood/peripheral blood mononuclear cells,and the cryo-resuscitated cell numbers and viability of derived NK cells/CIK cells did not show significant difference between the experimental and control groups.(3)For NK cells derived and differentiated from cord blood/peripheral blood mononuclear cells,there was no significant difference in the proportion of CD56+CD16+cell subpopulations between the experimental group and the control group.For CIK cells derived and differentiated from cord blood/peripheral blood mononuclear cells,there was no significant difference in the proportions of CD3+CD8+and CD3+CD56+cell subpopulations between the experimental group and the control group.(4)In terms of cytotoxicity testing,when the effective-target ratio of immune cells and melanoma cell line Mel624 was 20:1,whether it was NK cells/CIK cells derived from cord blood or peripheral blood mononuclear cells,there was no significant difference in the tumoricidal activity of cells between the experimental group and the control group.These findings suggest that the novel cryoprotectant can replace existing commercially available and widely used cryoprotectants,and is applicable to Wharton's jelly tissue,umbilical cord mesenchymal stem cells,umbilical cord blood/peripheral blood mononuclear cells,as well as NK and CIK cells,providing a solid technical foundation for the scaling,standardization,and commercialization of universal cryoprotectants.
9.Screening and Identification of Nanobodies Against β-Conglycinin
Jia-Shu CHANG ; Hua-Bo SUN ; Yu-Ting WANG ; Xiao-Hui WANG ; Bo YANG ; Hong-Rui LIU ; Yue-Xin LI ; Yuan-Zhao SUN ; Shao-Peng GU ; Jin-Xin HE
Chinese Journal of Biochemistry and Molecular Biology 2025;41(5):764-770
Soy is a vital source of plant carbohydrates.However,it poses significant allergenic risks,particularly to young children and animals.Among the various proteins in soy,β-conglycinin,which con-stitutes approximately 30%of total soy carbohydrates,is a primary allergen.Undigested β-conglycinin can lead to intestinal damage by inhibiting cell growth,disrupting the cytoskeleton,and inducing apopto-sis.It can also enter the lymphatic and circulatory systems,triggering allergic reactions.Conventional ELISA methods for detecting β-conglycinin rely on polyclonal or monoclonal antibodies,which are limited by their large molecular weight,difficulty in accessing the protein core,and sensitivity to acidic and bas-ic conditions.To address these limitations,this study aimed to develop nanobodies(Nbs)against β-con-glycinin.Nbs,derived from the variable regions of heavy-chain antibodies found in camelids,have a mo-lecular weight approximately one-tenth that of conventional antibodies.They offer advantages such as small size,stable structure,high specificity,and strong affinity.A female alpacas was immunized five times using β-conglycinin,which showed a heavy chain antibody potency of 1∶16 000 by ELISA.Pe-ripheral blood lymphocytes were subsequently isolated and total RNA was extracted.The variable region of the heavy-chain antibody was amplified via PCR,and recombinant plasmids were constructed and transformed into the E.coli competency strain ER2738.The resulting library contained about 3.5×108 CFU/mL,which increased to 1.15×1012 PFU/mL after phage rescue,with a 100%Nbs gene insertion rate,indicating high diversity.Its Nbs phage output was significantly enriched by four rounds of solid-phase elution with an enrichment rate of 155.9.Four rounds of solid-phase panning yielded 35 positive clones,all of which shared the same amino acid sequence upon sequencing.The selected Nb was ex-pressed in a prokaryotic system,and its binding ability to β-conglycinin was confirmed using Western blotting and ELISA.The results demonstrated excellent specificity and affinity.This research lays the groundwork for developing a rapid and efficient detection method for β-conglycinin using Nbs,potentially enhancing food safety and allergen management.
10.National bloodstream infection bacterial resistance surveillance report 2023: Gram-positive bacteria
Chaoqun YING ; Jinru JI ; Zhiying LIU ; Qing YANG ; Haishen KONG ; Jiangqin SONG ; Hui DING ; Yanyan LI ; Yuanyuan DAI ; Haifeng MAO ; Pengpeng TIAN ; Lu WANG ; Yongyun LIU ; Yizheng ZHOU ; Jiliang WANG ; Yan JIN ; Donghong HUANG ; Hongyun XU ; Peng ZHANG ; Xinhua QIANG ; Hong HE ; Lin ZHENG ; Junmin CAO ; Zhou LIU ; Ying HUANG ; Yan GENG ; Haiquan KANG ; Dan LIU ; Guolin LIAO ; Lixia ZHANG ; Fenghong CHEN ; Yanhong LI ; Baohua ZHANG ; Haixin DONG ; Xiaoyan LI ; Donghua LIU ; Qiuying ZHANG ; Xuefei HU ; Liang GUO ; Sijin MAN ; Dijing SONG ; Rong XU ; Youdong YIN ; Kunpeng LIANG ; Aiyun LI ; Zhuo LI ; Hongxia HU ; Guoping LU ; Jinhua LIANG ; Qiang LIU ; Yinqiao DONG ; Jilu SHEN ; Shuyan HU ; Liang LUAN ; Jian LI ; Ling MENG ; Dengyan QIAO ; Xiusan XIA ; Bo QUAN ; Dahong WANG ; Chunhua HAN ; Xiaoping YAN ; Fei LI ; Shifu WANG ; Ping SHEN ; Yunbo CHEN ; Yonghong XIAO
Chinese Journal of Clinical Infectious Diseases 2025;18(2):118-132
Objective:To report the nationwide surveillance results of pathogenic profiles and antimicrobial resistance patterns of Gram-positive bloodstream infections in China in 2023.Methods:The clinical isolates of Gram-posttive bacteria from blood cultures were collected in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System(BRICS)during January to December 2023. Antimicrobial susceptibility testing was performed using the dilution method recommended by the Clinical and Laboratory Standards Institute(CLSI). Statistical analyses were conducted using WHONET 5.6 and SPSS 25.0 software.Results:A total of 4 385 Gram-positive bacterial isolates were obtained from 60 participating center. The top five pathogens were Staphylococcus aureus( n=1 544,35.2%),coagulase-negative Staphylococci( n=1 441,32.9%), Enterococcus faecium( n=574,13.1%), Enterococcus faecalis( n=385,8.8%),and α-hemolytic Streptococci( n=187,4.3%). The prevalence of methicillin-resistant Staphylococcus aureus(MRSA)and methicillin-resistant coagulase-negative Staphylococci(MRCNS)was 26.2%(405/1 544)and 69.8%(1 006/1 441),respectively. Notably,all Staphylococci remained susceptible to glycopeptide or daptomycin. Staphylococcus aureus demonstrated excellent susceptibility(>97.0%)to cephalobiol,rifampicin,trimethoprim-sulfamethoxazole,linezolid,minocycline,tigecycline,and eravacycline. No Enterococcus exhibiting resistance to linezolid were detected. Glycopeptide resistance was uncommon but more frequent in Enterococcus faecium(resistance to vancomycin and teicoplanin:both 1.7%)compared to Enterococcus faecalis(both 0.3%). The detection rates of MRSA and MRCNS exhibited significant regional variations across the country( χ2=17.674 and 148.650,respectively,both P<0.001). No vancomycin-resistant Enterococci were detected in central China. Institutional comparison demonstrated higher prevalence of MRSA( χ2=14.111, P<0.001)and MRCNS( χ2=4.828, P=0.028)in provincial hospitals than that in municipal hospitals. Socioeconomic analysis identified elevated detection rates of both MRSA( χ2=18.986, P<0.001)and MRCNS( χ2=4.477, P=0.034)in less developed regions(per capita GDP

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