1.Influence of parental smoking and household secondhand smoke exposure on adolescents smoking initiation
SU Qi, XU Luting, SHI Jianhui, ZENG Xinying, LIU Ying, QI Mingxin, CAO Yuan, LIU Shiwei
Chinese Journal of School Health 2025;46(3):339-342
Objective:
To explore the impact of household tobacco smoke exposure on adolescents attempted smoking behavior, so as to provide a reference for tobacco control policy formulation and evaluation.
Methods:
From September to November 2023, a stratified cluster random sampling method was employed to select 7 841 middle and high school students from 10 monitoring sites (districts/counties) in Beijing for a questionnaire survey. Rao-Scott Chi square test was used to assess differences in proportions across subgroups, and complex sampling design based multivariate Logistic regression analysis was conducted to explore the influence of parental smoking and secondhand smoke (SHS) exposure at home on adolescents attempted smoking behavior.
Results:
About 47.17% of adolescents reported to have at least one parent smoked, with 42.36% reported of having only the father smoked, 0.73% reported of having only the mother smoked, and 4.08% reported of having both parents smoked. About 34.66% of middle and high school students were reported SHS exposure at home in the past 7 days, with 10.98%, 4.79% and 18.89% reported SHS exposure for 1-2, 3-4 and 5-7 days. Compared to adolescents with non smoking parents, those with a smoking father or both smoking parents had higher rates of attempted smoking [ OR (95% CI )=1.45(1.06-1.98), 3.73(2.18-6.37), P < 0.05 ]. Compared to adolescents without SHS exposure at home in the past 7 days, those exposed for 3-4 or 5- 7 days had higher rates of attempted smoking [ OR (95% CI )=2.21(1.27- 3.84 ), 2.46(1.58-3.83), P <0.01].
Conclusions
Household tobacco smoke exposure is associated with adolescent attempted smoking behavior. Parents should quit smoking and prohibit smoking at home to create a smoke free environment for adolescents.
2.Correlation between femoral offset,rotation center and leg length discrepancy after total hip arthroplasty based on digital analysis
Mao-Yong LI ; Wei CAO ; Pei-Xin SHA ; Xu-Dong SUN ; Shi-Yuan HUANG ; Kuan-Xin LI ; Heng ZHANG
China Journal of Orthopaedics and Traumatology 2024;37(4):381-386
Objective CT scans combined with Mimics software were used to measure femoral offset(FO),rotation center height(RCH)and lower leg length discrepancy(LLD)following total hip arthroplasty(THA),and the relationship between FO,RCH and LLD after THA is discussed.Methods Retrospective analysis was performed on 40 patients with unilateral THA who met standard cases from October 2020 to June 2022.There were 21 males and 19 females,18 patients on the left side and 22 patients on the right side,aged range from 30 to 81 years old,with an average age of(58.90±14.13)years old,BMI ranged from 17.3 to 31.5 kg·m-2withan average of(25.3±3.4)kg·m-2.There were 30 cases of femoral head necrosis(Ficattype Ⅳ),2 cases of hip osteoarthritis(Tonnis type Ⅲ),2 cases of developmental hip dislocation combined with end-stage osteoarthritis(Crowe type Ⅲ),and 6 cases of femoral neck fracture(Garden type Ⅳ).Three-dimensional CT reconstruction of pelvis was taken preoperative and postoperative,and three-dimensional reconstruction model was established after processing by Mimics software.FO,RCH and LLD were measured on the model.The criteria for FO reconstruction were as follows:postoperative bi-lateral FO difference less than 5 mm;the standard for equal length of both lower limbs was as follows:postoperative LLD differ-ence less than 5 mm.Results Bilateral FO difference was positively correlated with LLD(r=0.744,P<0.00l).Chi-square test was performed between the FO reconstructed group and the non-reconstructed eccentricity group:The results showed that the i-sometric ratio of lower limbs in the FO reconstructed group was significantly higher than that in the FO reconstructed group(x2=6.320,P=0.012).The bilateral RCH difference was significantly negatively correlated with LLD(r=-0.877,P<0.001).There is a linear relationship between bilateral FO difference and bilateral RCH difference and postoperative LLD,and the lin-ear regression equation is satisfied:postoperative LLD=0.038x-0.099y+0.257(x:postoperative bilateral FO difference,y:post-operative bilateral RCH difference;Unit:cm),F=77.993,R2=0.808,P=0.009.Conclusion After THA,LLD increased with the increase of FO and decreased with the increase of RCH.The effect of lower limb isometric length can be obtained more easily by reconstruction of FO.There is a linear relationship between the bilateral FO difference and the bilateral RCH difference after THA and LLD,and the regression equation can provide a theoretical reference forjudging LLD.
3.Predictive value of serum sFlt-1 and LTB4 for cerebral vasospasm after interventional embolization of intracranial aneurysms
Bing CAO ; Qi DING ; Yong-Da LIU ; Zhi-Wei DONG ; Yuan HOU ; Chun-Jiang LIU ; Xin-Wen XU
Journal of Regional Anatomy and Operative Surgery 2024;33(12):1062-1066
Objective To explore the predictive value of soluble fms-like tyrosine kinase-1(sFlt-1)and leukotriene B4(LTB4)in patients with intracranial aneurysms for cerebral vasospasm(CVS)after interventional embolization.Methods A total of 98 patients with intracranial aneurysms admitted to our hospital from January 2019 to September 2023 were regarded as the observation group,and were divided into the CVS group(32 cases)and the non CVS group(66 cases)according to whether CVS occurred or not within 3 to 5 days after surgery;102 healthy examinees in our hospital were selected as the control group.Enzyme-linked immunosorbent assay was used to detect serum levels of sFlt-1 and LTB4;the influencing factors for CVS after interventional embolization of intracranial aneurysms were analyzed by Logistic regression analysis;the predictive value of serum sFlt-1 and LTB4 levels for the occurrence of CVS after interventional embolization of intracranial aneurysms was analyzed by receiver operating characteristic(ROC)curve.Results The serum levels of sFlt-1 and LTB4 of patients in the observation group were obviously higher than those in the control group,and the differences were statistically significant(P<0.05).The serum levels of sFlt-1 and LTB4,and the proportions of patients with postoperative blood pressure fluctuation range≥30 mmHg and Hunt-Hess grade Ⅲ in the CVS group were obviously higher than those in the non CVS group,and the differences were statistically significant(P<0.05).SFlt-1(OR:2.985;95%CI:1.684 to 5.291)and LTB4(OR:2.868;95%CI:1.581 to 5.204)were the independent risk factors for CVS after interventional embolization of intracranial aneurysms(P<0.05).The area under the curve(AUC)of sFlt-1 and LTB4 alone and in combination for predicting the occurrence of CVS after interventional embolization of intracranial aneurysms were 0.839,0.825,and 0.915,respectively,with sensitivity of 84.44%,87.59%,and 81.36%,and specificity of 74.26%,75.87%,and 90.98%,respectively.The AUC of the combination of the two was higher than those of sFlt-1 and LTB4 alone,and the differences were statistically significant(Z=2.150,2.546,P<0.05).Conclusion The serum levels of sFlt-1 and LTB4 in patients with CVS after interventional embolization of intracranial aneurysms are increased,and the combination of the two can serve as the important indicators for predicting CVS.
4.Development and evaluation of a triplex RT-qPCR assay with internal references for detection of the Dengue and Zika viruses
Meng-Tao CAO ; Xiao-Yu HU ; Wei YANG ; Chun-Yuan LI ; Xiao-Li XU ; Rui-Wen REN ; Hong-Xia JIANG
Chinese Journal of Zoonoses 2024;40(6):537-543
A triplex RT-qPCR assay with human genes as internal references was established for detection of the Dengue and Zika viruses(DENV and ZIKV,respectively).The conserved regions of the four serotypes of DENV,along with the NS1 gene of ZIKV and the human β-actin gene,which is stably ex-pressed in various human tissues,were targeted by three sets of specific primers and probes.Standard plasmids for four se-rotypes of DENV,ZIKV,and β-actin were constructed as pos-itive controls.Optimal reaction conditions were determined through an L9(34)orthogonal experiment.The specificity,sensitivity,and coverage of the assay were verified and evalua-ted clinically,and the consistency was evaluated against a com-mercial kit for detection of DENV.The triplex RT-qPCR assay established exhibited no non-specific cross reactions with 12 similar arboviruses.The detection sensitivity for DENV and ZIKV were 2.99 and 2.18 copies/μL,respectively,and the intra-group and inter-group repeatability coefficients of variation were within 1.5%.As compared to the commercial kit,the proposed assay obtained positive results for 13 epidemic strains of DENV.Bland-Altman consistency analysis confirmed that the consistency of the detection results of clinical positive samples between the commercial kit and the proposed assay was 92.59%.The highly specific and sensitive triplex RT-qPCR assay with internal references is an effective tool for early and rapid differential identification of DENV and ZIKV.
5.Clinical features of hereditary leiomyomatosis and renal cell carcinoma syndrome-associated renal cell carcinoma: a multi-center real-world retrospective study
Yunze XU ; Wen KONG ; Ming CAO ; Guangxi SUN ; Jinge ZHAO ; Songyang LIU ; Zhiling ZHANG ; Liru HE ; Xiaoqun YANG ; Haizhou ZHANG ; Lieyu XU ; Yanfei YU ; Hang WANG ; Honggang QI ; Tianyuan XU ; Bo YANG ; Yichu YUAN ; Dongning CHEN ; Dengqiang LIN ; Fangjian ZHOU ; Qiang WEI ; Wei XUE ; Xin MA ; Pei DONG ; Hao ZENG ; Jin ZHANG
Chinese Journal of Urology 2024;45(3):161-167
Objective:To investigate the clinical features and therapeutic efficacy of patients with hereditary leiomyomatosis and renal cell carcinoma(RCC) syndrome-associated RCC (HLRCC-RCC) in China.Methods:The clinical data of 119 HLRCC-RCC patients with fumarate hydratase (FH) germline mutation confirmed by genetic diagnosis from 15 medical centers nationwide from January 2008 to December 2021 were retrospectively analyzed. Among them, 73 were male and 46 were female. The median age was 38(13, 74) years. The median tumor diameter was 6.5 (1.0, 20.5) cm. There were 38 cases (31.9%) in stage Ⅰ-Ⅱand 81 cases (68.1%) in stage Ⅲ-Ⅳ. In this group, only 11 of 119 HLRCC-RCC patients presented with skin smooth muscle tumors, and 44 of 46 female HLRCC-RCC patients had a history of uterine fibroids. The pathological characteristics, treatment methods, prognosis and survival of the patients were summarized.Results:A total of 86 patients underwent surgical treatment, including 70 cases of radical nephrectomy, 5 cases of partial nephrectomy, and 11 cases of reductive nephrectomy. The other 33 patients with newly diagnosed metastasis underwent renal puncture biopsy. The results of genetic testing showed that 94 patients had FH gene point mutation, 18 had FH gene insertion/deletion mutation, 4 had FH gene splicing mutation, 2 had FH gene large fragment deletion and 1 had FH gene copy number mutation. Immunohistochemical staining showed strong 2-succinocysteine (2-SC) positive and FH negative in 113 patients. A total of 102 patients received systematic treatment, including 44 newly diagnosed patients with metastasis and 58 patients with postoperative metastasis. Among them, 33 patients were treated with tyrosine kinase inhibitor (TKI) combined with immune checkpoint inhibitor (ICI), 8 patients were treated with bevacizumab combined with erlotinib, and 61 patients were treated with TKI monotherapy. Survival analysis showed that the median progression-free survival (PFS) of TKI combined with ICI was 18 (5, 38) months, and the median overall survival (OS) was not reached. The median PFS and OS were 12 (5, 14) months and 30 (10, 32) months in the bevacizumab combined with erlotinib treatment group, respectively. The median PFS and OS were 10 (3, 64) months and 44 (10, 74) months in the TKI monotherapy group, respectively. PFS ( P=0.009) and OS ( P=0.006) in TKI combined with ICI group were better than those in bevacizumab combined with erlotinib group. The median PFS ( P=0.003) and median OS ( P=0.028) in TKI combined with ICI group were better than those in TKI monotherapy group. Conclusions:HLRCC-RCC is rare but has a high degree of malignancy, poor prognosis and familial genetic characteristics. Immunohistochemical staining with strong positive 2-SC and negative FH can provide an important basis for clinical diagnosis. Genetic detection of FH gene germ line mutation can confirm the diagnosis. The preliminary study results confirmed that TKI combined with ICI had a good clinical effect, but it needs to be confirmed by the results of a large sample multi-center randomized controlled clinical study.
6.Establishment and evaluation of a quantitative PCR-based assay for the detection of Mycobacterium marinum in skin biopsy specimens
Zhaojun YUAN ; Lele SUN ; Yuanhang SUN ; Yong ZHANG ; Yuanyuan CAO ; Xu SANG ; Zige LI ; Meng WANG ; Yanru CHENG ; Yanyan LI ; Qing PAN ; Fangfang BAO ; Hong LIU ; Furen ZHANG
Chinese Journal of Dermatology 2024;57(11):1022-1028
Objective:To establish a rapid quantitative PCR (qPCR) technique for Mycobacterium marinum skin infections, and to analyze its clinical diagnostic efficiency. Methods:DNA was extracted from Mycobacterium marinum colonies and serially diluted (10 -1 to 10 -8). Twelve pairs of previously reported primers and probes, as well as 6 pairs of newly designed primers and probes in this study, were used for qPCR amplification to identify the most sensitive primers and probes for the detection of Mycobacterium marinum. Skin lesion tissues were collected from 72 patients with confirmed Mycobacterium marinum infections (experimental group) and 68 with other mycobacterial infections (control group) at Shandong Provincial Hospital for Skin Diseases & Shandong Provincial Institute of Dermatology and Venereology, Shandong First Medical University & Shandong Academy of Medical Sciences in 2021. These skin tissues were subjected to qPCR amplification, interferon-gamma release assay (IGRA), acid-fast staining, and tissue culture to evaluate the diagnostic efficacy. Results:The newly designed primers and probes targeting the mycobacterial enhanced infection locus 2 (Mel2) demonstrated the highest sensitivity, with a detection limit of 0.86 copies/μl (cycle threshold value = 37) ; the qPCR amplification with the Mel2 primers/probes did not yield positive results when used for the detection of other mycobacteria (including Mycobacterium leprae and Staphylococcus spp) . Among the 72 patients in the experimental group, 44 were positive for qPCR with a sensitivity of 61.1% (95% CI: 49.6% - 71.5%), and 47 were positive for culture with a sensitivity of 65.2% (95% CI: 53.8% - 75.3%) ; all the 68 controls were negative for both qPCR and culture, with their specificities both being 100%. Among 65 patients subjected to IGRA, 31 were positive with a sensitivity of 47.7% (95% CI: 36.0% - 59.6%), while 16 out of 25 controls were negative for IGRA with a specificity of 64.0% (95% CI: 44.5% - 79.8%). Among 58 patients subjected to acid-fast staining, 37 were positive with a sensitivity of 63.8% (95% CI: 50.9% - 74.9%), and 52 out of 66 controls were negative for acid-fast staining with a specificity of 78.8% (95% CI: 67.5% - 86.9%). The combination of qPCR and culture resulted in a sensitivity of 93% and a specificity of 100% for the detection of Mycobacterium marinum. Conclusion:In this study, a highly sensitive qPCR assay was developed for the detection of Mycobacterium marinum, and its combination with culture could further improve the detection sensitivity.
7.Vaccarin alleviates mitochondrial damage and endothelial dysfunction in type 2 diabetes by regulating miR-570-3p/BNIP3 pathway
Chenyang ZHAO ; Xuexue ZHU ; Xinyu CHEN ; Tianxiao CHEN ; Jinpeng XU ; Tai-Yue LI ; Xingyu CAO ; Yuan ZHANG ; Liying QIU
Chinese Journal of Pathophysiology 2024;40(5):872-881
AIM:To investigate the effect of vaccarin(VAC)on endothelial dysfunction in type 2 diabetes mellitus(T2DM),and to uncover the underlying mechanisms.METHODS:(1)C57BL/6 mice received intraperitoneal injection of streptozotocin and were fed with a high-fat diet(21.8 kJ/kg,60%of the energy source was fat)to construct a T2DM mouse model.Thirty mice were randomly divided into control,T2DM and T2DM+VAC groups,with 10 mice in each group.The mice in T2DM+VAC group were given 1 mg/kg VAC via oral gavage for 6 weeks,while those in control and T2DM groups were given the same volume of PBS.The mRNA and protein expression levels of BCL2-interacting pro-tein 3(BNIP3),PTEN-induced kinase 1(PINK1)and parkin in the thoracic aorta were detected by RT-qPCR and West-ern blot.(2)Human umbilical vein endothelial cells(HUVECs)were stimulated by high glucose(HG;35 mmol/L glu-cose).Mitochondrial membrane potential,autophagy and mitochondrial superoxide levels were detected using JC-1,acri-dine orange(AO)and MitoSOX staining,respectively.RESULTS:Compared with control group,the mRNA and protein levels of BNIP3,PINK1 and parkin were significantly increased in the thoracic aorta of T2DM mice(P<0.05).Compared with T2DM group,the mRNA and protein levels of BNIP3,PINK1 and parkin in the thoracic aorta were significantly re-duced in T2DM+VAC group(P<0.05).The results of JC-1,AO and MitoSOX staining showed that VAC attenuated the decrease in mitochondrial membrane potential and the increase in autophagy and mitochondrial superoxide levels in HG-in-duced HUVECs.Treatment with VAC also inhibited HG-mediated mitochondrial damage in HUVECs after BNIP3 overex-pression.The effect of miR-570-3p mimic on mitochondrial damage was similar to VAC.RT-qPCR and Western blot showed that both miR-570-3p mimic and VAC significantly reduced the mRNA and protein levels of BNIP3,PINK1 and parkin.In contrast,inhibition of miR-570-3p exhibited the opposite effects.CONCLUSION:Treatment with VAC alle-viated endothelial dysfunction in T2DM by inhibiting HG-induced mitochondrial dysfunction through miR-570-3p/BNIP3.
8.A multi-center epidemiological study on pneumococcal meningitis in children from 2019 to 2020
Cai-Yun WANG ; Hong-Mei XU ; Gang LIU ; Jing LIU ; Hui YU ; Bi-Quan CHEN ; Guo ZHENG ; Min SHU ; Li-Jun DU ; Zhi-Wei XU ; Li-Su HUANG ; Hai-Bo LI ; Dong WANG ; Song-Ting BAI ; Qing-Wen SHAN ; Chun-Hui ZHU ; Jian-Mei TIAN ; Jian-Hua HAO ; Ai-Wei LIN ; Dao-Jiong LIN ; Jin-Zhun WU ; Xin-Hua ZHANG ; Qing CAO ; Zhong-Bin TAO ; Yuan CHEN ; Guo-Long ZHU ; Ping XUE ; Zheng-Zhen TANG ; Xue-Wen SU ; Zheng-Hai QU ; Shi-Yong ZHAO ; Lin PANG ; Hui-Ling DENG ; Sai-Nan SHU ; Ying-Hu CHEN
Chinese Journal of Contemporary Pediatrics 2024;26(2):131-138
Objective To investigate the clinical characteristics and prognosis of pneumococcal meningitis(PM),and drug sensitivity of Streptococcus pneumoniae(SP)isolates in Chinese children.Methods A retrospective analysis was conducted on clinical information,laboratory data,and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country.Results Among the 160 children with PM,there were 103 males and 57 females.The age ranged from 15 days to 15 years,with 109 cases(68.1% )aged 3 months to under 3 years.SP strains were isolated from 95 cases(59.4% )in cerebrospinal fluid cultures and from 57 cases(35.6% )in blood cultures.The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87)and 27% (21/78),respectively.Fifty-five cases(34.4% )had one or more risk factors for purulent meningitis,113 cases(70.6% )had one or more extra-cranial infectious foci,and 18 cases(11.3% )had underlying diseases.The most common clinical symptoms were fever(147 cases,91.9% ),followed by lethargy(98 cases,61.3% )and vomiting(61 cases,38.1% ).Sixty-nine cases(43.1% )experienced intracranial complications during hospitalization,with subdural effusion and/or empyema being the most common complication[43 cases(26.9% )],followed by hydrocephalus in 24 cases(15.0% ),brain abscess in 23 cases(14.4% ),and cerebral hemorrhage in 8 cases(5.0% ).Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old,with rates of 91% (39/43)and 83% (20/24),respectively.SP strains exhibited complete sensitivity to vancomycin(100% ,75/75),linezolid(100% ,56/56),and meropenem(100% ,6/6).High sensitivity rates were also observed for levofloxacin(81% ,22/27),moxifloxacin(82% ,14/17),rifampicin(96% ,25/26),and chloramphenicol(91% ,21/23).However,low sensitivity rates were found for penicillin(16% ,11/68)and clindamycin(6% ,1/17),and SP strains were completely resistant to erythromycin(100% ,31/31).The rates of discharge with cure and improvement were 22.5% (36/160)and 66.2% (106/160),respectively,while 18 cases(11.3% )had adverse outcomes.Conclusions Pediatric PM is more common in children aged 3 months to under 3 years.Intracranial complications are more frequently observed in children under 1 year old.Fever is the most common clinical manifestation of PM,and subdural effusion/emphysema and hydrocephalus are the most frequent complications.Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates.Adverse outcomes can be noted in more than 10% of PM cases.SP strains are high sensitivity to vancomycin,linezolid,meropenem,levofloxacin,moxifloxacin,rifampicin,and chloramphenicol.[Chinese Journal of Contemporary Pediatrics,2024,26(2):131-138]
9.Feasibility of low-dose CT brain perfusion scanning based on deep learning reconstruction algorithm: a preliminary study
Limin LEI ; Yuhan ZHOU ; Xiaoxu GUO ; Hui WANG ; Jinping MA ; Zhihao WANG ; Weimeng CAO ; Yuan GAO ; Yuming XU ; Songwei YUE
Chinese Journal of Radiological Medicine and Protection 2024;44(7):613-621
Objective:To compare image quality and diagnostic parameters of whole-brain CT perfusion scans under different scanning conditions and assess the utility of deep learning image reconstruction algorithm (DLIR) in reducing tube current during low-dose scans.Methods:Method A total of 105 patients with suspected acute ischemic stroke (AIS) were prospectively enrolled in the First Affiliated Hospital of Zhengzhou University from March, 2022 to March, 203 and their baseline information was recorded. All patients underwent head non-contrast CT and CT perfusion (CTP) examinations. CTP scanning was performed at 80 kV in two groups with the tube current of 150 mA (regular dose) and 100 mA (low dose), respectively. The CTP images of 150 mA group were reconstructed using filtered back-projection algorithm as well as adaptive statistical iterative reconstruction-V (ASIR-V) at 40% and 80% strength levels, which were denoted as groups A-C. The CTP images of 100 mA group were reconstructed using ASIR-V80%, DLIR-M, and DLIR-H, which were denoted as groups D-F. Clinical baseline characteristics and radiation doses were compared between the two groups under different scanning conditions. Furthermore, we assessed the subjective and objective image quality, conventional perfusion parameters, and abnormal perfusion parameters of AIS patients across the six groups of reconstructed CTP images.Results:Under the scanning conditions of 150 mA and 100 mA, 47 and 48 patients were diagnosed with AIS, respectively. There were no significant differences in the baseline characteristics between the two groups. However, there was a significant difference in the mean effective radiation dose (5.71 mSv vs. 3.80 mSv, t = 2 768.30, P < 0.001). The standard deviation (SD) of noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) of gray matter (GM) and white matter (WM) were significantly different among the six groups of reconstructed images ( F = 40.58-212.13, P < 0.001). In GM, the SD values in groups C, D, and F were lower than those in other groups ( P < 0.05), and the SNR values in groups C and F were higher than those in other groups ( P < 0.05). In WM, the SD and SNR values in groups C and F were significantly different from those in other groups ( P < 0.05). Additionally, CNR values in groups C and F were higher than those in other groups ( P < 0.05). There was no significant difference in subjective scores among groups B, C, and F ( P > 0.05). Regarding perfusion parameters in the brain GM, groups D and E had lower cerebral blood volume (CBV) values compared to groups A to C ( P < 0.05), and group F had lower CBV values than group B ( P < 0.05). In the brain WM, group D had consistently lower mean transit time (MTT) values compared to the other groups ( P < 0.05). Notably, there were no significant differences in AIS lesion detection rates and relevant diagnostic parameters across the six image groups. Conclusions:Low-tube current CTP scan combined with the DLIR-H algorithm can enhance image quality without affecting perfusion parameters such as CBV and MTT, while reducing radiation dose by 30%. This algorithm can be routinely applied in brain CTP examinations.
10.Finite element model establishment and stress analysis of lumbar-sacral intervertebral disc in ankylosing spondylitis
Zhijie KANG ; Zhenhua CAO ; Yangyang XU ; Yunfeng ZHANG ; Feng JIN ; Baoke SU ; Lidong WANG ; Ling TONG ; Qinghua LIU ; Yuan FANG ; Lirong SHA ; Liang LIANG ; Mengmeng LI ; Yifei DU ; Lin LIN ; Haiyan WANG ; Xiaohe LI ; Zhijun LI
Chinese Journal of Tissue Engineering Research 2024;28(6):840-846
BACKGROUND:Ankylosing spondylitis is a chronic inflammatory disease with chronic rheumatic immunity.Soft tissue ossification and fusion and spinal stiffness can cause biomechanical changes. OBJECTIVE:To reconstruct the lumbar-sacral intervertebral disc in ankylosing spondylitis patients with lumbar kyphosis by finite element analysis,and to study the range of motion of each segment of T11-S1 and the biomechanical characteristics of annulus fibrosus and nucleus pulposus. METHODS:The imaging data were obtained from an ankylosing spondylitis patient with lumbar kyphosis.The original CT image data of continuously scanned spine were imported into Mimics 21.0 in DICOM format,and T11-S1 was reconstructed respectively.The established model was imported into 3-Matic software in the format of"Stl"to reconstruct the intervertebral disc,and the fibrous intervertebral disc model was obtained.The improved model was further imported into Hypermesh software,and the vertebra,nucleus pulposus,annulus fibrosus and ligament were mesh-divided.After the material properties were given,the model was imported into ABAQUS software to observe the range of motion of each vertebral body in seven different working conditions of T11-S1,and analyze the biomechanical characteristics of each segment of annulus fibrosus and nucleus pulposus. RESULTS AND CONCLUSION:(1)The range of motion of L1 vertebrae was higher than that of other vertebrae under six different working conditions:extension,forward flexion,rotation(left and right),and lateral flexion(left and right).The maximum range of motion was 2.18° during L1 vertebral flexion,and the minimum range of motion was 0.12° during L5 vertebral extension.(2)The annular fiber flexion at L2-L3 segments was greater than the extension(P<0.05),and the annular fiber flexion at L3-L4 and L4-L5 segments was less than the extension(P<0.05).The left rotation of L1-L2 annular fibers was greater than the right rotation(P<0.05).The left flexion of the annulus was greater than the right flexion in L1-L2,L2-L3,L3-L4,L4-L5 and L5-S1 segments(P<0.05).(3)The nucleus pulposus stresses of T11-L12,L1-L2,L2-L3,L3-L4 and L4-L5 segments in forward flexion were greater than in extension(P<0.05).The left rotation of T12-L1 and L3-L4 segments was smaller than the right rotation(P<0.05),and that of T11-T12,L1-L2,and L2-L3 segments was larger than the right rotation(P<0.05).The left flexion was larger than the right flexion in the T11-S1 segment.(4)It is concluded that in ankylosing spondylitis patients with lumbar kyphosis,the minimum range of motion of the vertebral body is located at the L5 vertebral body in extension.To prevent fractures,it is recommended to avoid exercise in the extension position.During the onset of lumbar kyphosis in patients with ankylosing spondylitis,the maximum stress of the annulus fibrosus and nucleus pulposus is located in the L1-L2 segment,which is fixed and will not alter with the change of body position.The late surgical treatment and correction of deformity should focus on releasing the pressure of the annulus fibrosus and nucleus pulposus in this segment to avoid the rupture of the annulus fibrosus and the injury of the nucleus pulposus.


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