1.Nanocrystalline collagen-based bone combined with Bushen Zhuangjin Decoction repairs bone defects in osteoporotic rats
Shibo ZHOU ; Xing YU ; Hailong CHEN ; Yang XIONG
Chinese Journal of Tissue Engineering Research 2026;30(2):354-361
BACKGROUND:The previous study of the research group confirmed that Bushen Zhuangjin Decoction can regulate bone metabolism and play an anti-osteoporosis role,and nanocrystalline collagen-based bone can assist in the repair of limb bone defects.OBJECTIVE:To explore the repair effect of nanocrystalline collagen-based bone combined with Bushen Zhuangjin Decoction on osteoporotic bone defects.METHODS:Totally 84 female SD rats were randomly divided into a sham operation group(n=6,no modeling)and a bilateral ovariectomy group(n=78).After 12 weeks of bilateral ovariectomy,the sham operation group(n=6)and the bilateral ovariectomy group(n=6)were selected for osteoporosis modeling verification.The remaining 72 rats in the bilateral ovariectomy group were randomly divided into 6 intervention groups,with 12 rats in each group:groups A-E had femoral defect models(diameter 3.5 mm,depth 4 mm)established 12 weeks after bilateral ovariectomy.Group A was given double distilled water by gavage(once a day)after surgery;group B was given Bushen Zhuangjin Decoction by gavage(once a day)after surgery;group C had nanocrystalline collagen-based bone filled in the bone defect and then given double distilled water by gavage(once a day);group D had nanocrystalline collagen-based bone filled in the bone defect and then given alendronate sodium by gavage(once a week);group E had nanocrystalline collagen-based bone filled in the bone defect and then given Bushen Zhuangjin Decoction by gavage(once a day);group F had femoral defect models established at the same time after bilateral ovariectomy,and bone defect sites were filled with nanocrystalline collagen-based bone and then given Bushen Zhuangjin Decoction by gavage(once a day).All drugs were given continuously for 12 weeks.12 hours after the last administration,serum levels of type Ⅰ procollagen amino-terminal propeptide,type Ⅰ collagen cross-linked C-terminal peptide,and estradiol were detected;bone volume in the bone defect area was detected by Micro-CT.The expression of type Ⅰ collagen and vascular endothelial growth factor in the bone defect area was detected by immunohistochemical staining.RESULTS AND CONCLUSION:(1)Compared with group A,the serum level of type Ⅰ procollagen amino-terminal propeptide in groups D and E was decreased(P<0.05).Compared with groups A and C,the serum estradiol level in groups D,E,and F was increased(P<0.05).There was no significant difference in the bone volume in the defect area between groups A-F(P>0.05).(2)Immunohistochemical staining showed that compared with group A,the expression of typeⅠ collagen and vascular endothelial growth factor in groups B,D,and E increased(P<0.05).Compared with group C,the expression of type Ⅰ collagen in groups B,D,E,and F increased(P<0.05),and the expression of vascular endothelial growth factor in groups D,E,and F increased(P<0.05).(3)The results show that nanocrystalline collagen-based bone combined with Bushen Zhuangjin Decoction may have the potential to repair bone defects in ovariectomized osteoporotic rats.
2.Nanocrystalline collagen-based bone combined with Bushen Zhuangjin Decoction repairs bone defects in osteoporotic rats
Shibo ZHOU ; Xing YU ; Hailong CHEN ; Yang XIONG
Chinese Journal of Tissue Engineering Research 2026;30(2):354-361
BACKGROUND:The previous study of the research group confirmed that Bushen Zhuangjin Decoction can regulate bone metabolism and play an anti-osteoporosis role,and nanocrystalline collagen-based bone can assist in the repair of limb bone defects.OBJECTIVE:To explore the repair effect of nanocrystalline collagen-based bone combined with Bushen Zhuangjin Decoction on osteoporotic bone defects.METHODS:Totally 84 female SD rats were randomly divided into a sham operation group(n=6,no modeling)and a bilateral ovariectomy group(n=78).After 12 weeks of bilateral ovariectomy,the sham operation group(n=6)and the bilateral ovariectomy group(n=6)were selected for osteoporosis modeling verification.The remaining 72 rats in the bilateral ovariectomy group were randomly divided into 6 intervention groups,with 12 rats in each group:groups A-E had femoral defect models(diameter 3.5 mm,depth 4 mm)established 12 weeks after bilateral ovariectomy.Group A was given double distilled water by gavage(once a day)after surgery;group B was given Bushen Zhuangjin Decoction by gavage(once a day)after surgery;group C had nanocrystalline collagen-based bone filled in the bone defect and then given double distilled water by gavage(once a day);group D had nanocrystalline collagen-based bone filled in the bone defect and then given alendronate sodium by gavage(once a week);group E had nanocrystalline collagen-based bone filled in the bone defect and then given Bushen Zhuangjin Decoction by gavage(once a day);group F had femoral defect models established at the same time after bilateral ovariectomy,and bone defect sites were filled with nanocrystalline collagen-based bone and then given Bushen Zhuangjin Decoction by gavage(once a day).All drugs were given continuously for 12 weeks.12 hours after the last administration,serum levels of type Ⅰ procollagen amino-terminal propeptide,type Ⅰ collagen cross-linked C-terminal peptide,and estradiol were detected;bone volume in the bone defect area was detected by Micro-CT.The expression of type Ⅰ collagen and vascular endothelial growth factor in the bone defect area was detected by immunohistochemical staining.RESULTS AND CONCLUSION:(1)Compared with group A,the serum level of type Ⅰ procollagen amino-terminal propeptide in groups D and E was decreased(P<0.05).Compared with groups A and C,the serum estradiol level in groups D,E,and F was increased(P<0.05).There was no significant difference in the bone volume in the defect area between groups A-F(P>0.05).(2)Immunohistochemical staining showed that compared with group A,the expression of typeⅠ collagen and vascular endothelial growth factor in groups B,D,and E increased(P<0.05).Compared with group C,the expression of type Ⅰ collagen in groups B,D,E,and F increased(P<0.05),and the expression of vascular endothelial growth factor in groups D,E,and F increased(P<0.05).(3)The results show that nanocrystalline collagen-based bone combined with Bushen Zhuangjin Decoction may have the potential to repair bone defects in ovariectomized osteoporotic rats.
3.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.
4.The Mesencephalic Locomotor Region for Locomotion Control
Xing-Chen GUO ; Yan XIE ; Xin-Shuo WEI ; Wen-Fen LI ; Ying-Yu SUN
Progress in Biochemistry and Biophysics 2025;52(7):1804-1816
Locomotion, a fundamental motor function encompassing various forms such as swimming, walking, running, and flying, is essential for animal survival and adaptation. The mesencephalic locomotor region (MLR), located at the midbrain-hindbrain junction, is a conserved brain area critical for controlling locomotion. This review highlights recent advances in understanding the MLR’s structure and function across species, from lampreys to mammals and birds, with a particular focus on insights gained from optogenetic studies in mammals. The goal is to uncover universal strategies for MLR-mediated locomotor control. Electrical stimulation of the MLR in species such as lampreys, salamanders, cats, and mice initiates locomotion and modulates speed and patterns. For example, in lampreys, MLR stimulation induces swimming, with increased intensity or frequency enhancing propulsive force. Similarly, in salamanders, graded stimulation transitions locomotor outputs from walking to swimming. Histochemical studies reveal that effective MLR stimulation sites colocalize with cholinergic neurons, suggesting a conserved neurochemical basis for locomotion control. In mammals, the MLR comprises two key nuclei: the cuneiform nucleus (CnF) and the pedunculopontine nucleus (PPN). Both nuclei contain glutamatergic and GABAergic neurons, with the PPN additionally housing cholinergic neurons. Optogenetic studies in mice by selectively activating glutamatergic neurons have demonstrated that the CnF and PPN play distinct roles in motor control: the CnF drives rapid escape behaviors, while the PPN regulates slower, exploratory movements. This functional specialization within the MLR allows animals to adapt their locomotion patterns and speed in response to environmental demands and behavioral objectives. Similar to findings in lampreys, the CnF and PPN in mice transmit motor commands to spinal effector circuits by modulating the activity of brainstem reticular formation neurons. However, they achieve this through distinct reticulospinal pathways, enabling the generation of specific behaviors. Further insights from monosynaptic rabies viral tracing reveal that the CnF and PPN integrate inputs from diverse brain regions to produce context-appropriate behaviors. For instance, glutamatergic neurons in the PPN receive signals from other midbrain structures, the basal ganglia, and medullary nuclei, whereas glutamatergic neurons in the CnF rarely receive inputs from the basal ganglia but instead are strongly influenced by the periaqueductal grey and inferior colliculus within the midbrain. These differential connectivity patterns underscore the specialized roles of the CnF and PPN in motor control, highlighting their unique contributions to coordinating locomotion. Birds exhibit exceptional flight capabilities, yet the avian MLR remains poorly understood. Comparative studies suggest that the pedunculopontine tegmental nucleus (PPTg) in birds is homologous to the mammalian PPN, which contains cholinergic neurons, while the intercollicular nucleus (ICo) or nucleus isthmi pars magnocellularis (ImC) may correspond to the CnF. These findings provide important clues for identifying the avian MLR and elucidating its role in flight control. However, functional validation through targeted experiments is urgently needed to confirm these hypotheses. Optogenetics and other advanced techniques in mice have greatly advanced MLR research, enabling precise manipulation of specific neuronal populations. Future studies should extend these methods to other species, particularly birds, to explore unique locomotor adaptations. Comparative analyses of MLR structure and function across species will deepen our understanding of the conserved and evolved features of motor control, revealing fundamental principles of locomotion regulation throughout evolution. By integrating findings from diverse species, we can uncover how the MLR has been adapted to meet the locomotor demands of different environments, from aquatic to aerial habitats.
5.Comparison of the hemodynamic effects of remimazolam tosylate and etomidate for anesthetic induction in elderly frail patients
Xiao-Yu TAO ; Shuang-Shuang GUAN ; Chen-Xu DAI ; Qiu-Feng WANG ; Hui-Hui LI ; Xing-Jun MA ; Ning CAI
Medical Journal of Chinese People's Liberation Army 2025;50(8):958-963
Objective To compare the hemodynamic effects of anesthesia induction with remimazolam tosylate and etomidate in elderly frail patients.Methods This study was a single-center,prospective,randomized,single-blind trial.From January to April 2024,96 elderly frail patients undergoing elective surgery in Fuyang People's Hospital were recruited.After excluding 6 cases(3 refused to participate,1 had tracheal intubation time>30 s,and 2 had missing data),90 patients were finally included.They were randomly divided into remimazolam tosylate group(intravenous injection of 0.2 mg/kg remimazolam tosylate for anesthesia induction,n=45)and etomidate group(intravenous injection of 0.3 mg/kg etomidate for anesthesia induction,n=45)by the random number table method.The area under the curve for mean arterial pressure(MAP)below or above baseline values(AUCMAP-and AUCMAP+),the heart rate(HR)below or above baseline values by 10%(AUCHR-and AUCHR+)within 10 minutes of anesthesia induction,the time to loss of consciousness,the time from the start of anesthesia induction to a bispectral index(BIS)<60,the incidence of drug-related adverse reactions,the incidence of cardiovascular adverse events,and the usage of vasoactive drug administrations were compared between the two groups.Results Compared with the etomidate group,the AUCMAP-(145.10±35.75 vs.178.52±39.78)and AUCHR-[43.20(26.58,56.35)vs.54.99(43.01,65.85)]in remimazolam tosylate group were significantly reduced(P<0.001,P=0.001).The time to loss of consciousness and the time from the start of anesthesia induction to BIS<60 were prolonged(P<0.001).The incidence of drug-related adverse reactions was significantly decreased(P<0.05),and the number of norepinephrine administrations was significantly reduced(P<0.05)in remimazolam tosylate group.However,there were no statistically significant differences in AUCMAP+,AUCHR+,the incidence of cardiovascular adverse events,and the usages of atropine,urapidil,and esmolol between the two groups(P>0.05).Conclusion The use of remimazolam tosylate during anesthesia induction in elderly frail patients can provide more stable hemodynamic parameters and results in fewer adverse reactions than etomidate.
6.Correlation analysis between stenosis characteristics and trans-stenotic pressure gradient using a 3D-printed hemodynamic simulation system for cerebral venous sinuses
Jia-Hao ZHANG ; Lei GENG ; Zhi-Tao XIAO ; Xing CHEN ; Zhe JI ; Xiang-Yu CAO
Medical Journal of Chinese People's Liberation Army 2025;50(11):1426-1432
Objective To analyze the relationship between different degrees of cerebral venous sinus stenosis and the trans-stenotic pressure gradient using a 3D-printed hemodynamic simulation system for cerebral venous sinuses.Methods Based on the double elastic cavity model,a complete morphological model of the superior sagittal sinus,transverse sinus,and sigmoid sinuses was constructed using 3D printing technology.An in vitro hemodynamic simulation system incorporating pulsatile blood flow was established to simulate the hemodynamic environment of cerebral venous sinus stenosis.Using this system,both unilateral dominant drainage and bilateral balanced drainage were simulated.The degree of stenosis and the pressure upstream and downstream of the stenosis were measured.The pressure difference and pressure ratio were calculated to analyze the correlation between stenosis degree and the trans-stenotic pressure gradient.Results In the unilateral dominant drainage model,as the stenosis severity increased,the upstream pressure increased,whereas the downstream pressure remained relatively stable,leading to an increased pressure gradient between the two ends.The regression equation for stenosis degree(X)and pressure gradient(pressure difference ΔP)was:YΔP=1.962X-1.417(R=0.867,R2=0.753,P<0.001).In the bilateral balanced drainage model of cerebral venous sinuses,when the stenosis degree on one side of the model increased,the pressure gradient between the two ends changed slightly and eventually reached a stable state.The regression equation between X and ΔP was:YΔP=0.62X+1.047(R=0.98,R2=0.96,P<0.001).Conclusions Stenosis in cerebral venous sinuses with unilateral dominant drainage has a more significant impact on the pressure gradient,while unilateral stenosis in bilateral cerebral venous sinuses with balanced drainage has a smaller impact on the pressure gradient.This result suggests that for bilateral venous sinus stenosis,stent implantation can be prioritized in one side of the cerebral venous sinuses.
7.CURRENT DISTRIBUTION OF AEDES AEGYPTI IN LEIZHOU PENINSULA,ZHANJIANG CITY,GUANGDONG PROVINCE
Rui-Peng LU ; Jin-Hua DUAN ; Yu-Wen ZHONG ; Hui DENG ; Jun WU ; Li-Ping LIU ; Wei-Xiong YIN ; Feng XING ; Hui HUANG ; Chang-Jie FU ; Zong-Jing CHEN ; Ming-Ji CHENG ; Sheng-Jun HU ; Ya-Ting CHEN ; Wen-Ting GUO ; Li-Feng LIN
Acta Parasitologica et Medica Entomologica Sinica 2025;32(1):16-21
Objective To investigate the status of population dynamics and distribution changes of Aedes aegypti in Guangdong Province.Methods Continuous monitoring was conducted from May 2018 to July 2024 in Wushi Town and Qishui Town,Leizhou City,Zhanjiang City,Guangdong Province.Additionally,a survey of the distribution of Ae.aegypti along the Leizhou Peninsula coast was carried out.Results The density of Ae.aegypti in Zhanjiang showed a gradual decline from 2018 to 2024.The last detection of adult Ae.aegypti in Wushi Town was in September 2021,and the last larva was found in October 2023.No Ae.aegypti was detected in Qishui Town during surveys from 2021 to 2024.A survey of 18 coastal villages in the Leizhou Peninsula revealed no detections of Ae.aegypti.Conclusions This study provides a basis for understanding the distribution and population density fluctuations of Ae.aegypti,assessing its invasion risk,and scientifically conducting relevant prevention and control efforts.
8.Effect of Different Time Interventions of Yangxin Tongmai Formula (养心通脉方) on DNA Methylation in Rat Models of Premature Coronary Heart Disease with Blood Stasis Syndrome
Xing CHEN ; Zixuan YU ; Shumeng ZHANG ; Yanjuan LIU ; Shuangyou DENG ; Ying WANG ; Lingli CHEN ; Jie LI
Journal of Traditional Chinese Medicine 2025;66(11):1165-1173
ObjectiveTo observe the effect of Yangxin Tongmai Formula (养心通脉方) by midnight-noon ebb-flow administration method for rat models of premature coronary heart disease (PCHD) with blood stasis syndrome, and to explore the possible mechanism of action from the perspective of DNA methylation differential gene expression. MethodsThere were 3 SD rats in each of the blank group, model group and Yangxin Tongmai Formula group, and the rats in the model group and Yangxin Tongmai Formula group were fed with high-fat chow plus vitamin D3 by gavage plus isoproterenol hydrochloride by subcutaneous injection to construct rat models of PCHD with blood stasis syndrome. After successful modelling, rats in Yangxin Tongmai Formula group were gavaged with 18 g/(kg‧d) of Yangxin Tongmai Formula, and rats in blank group and the model group were gavaged with 4 ml/(kg‧d) of 0.9% NaCl solution, and serum samples of rats in each group were collected for DNA methylation sequencing after 3 weeks to screen for the relevant DNA methylation differentiation genes. In addition, rats with successful modelling of PCHD with blood stasis were randomly divided into model group, Yangxin Tongmai Formula with midnight-noon ebb-flow administration method group [18 g/(kg‧d) of Yangxin Tongmai Formula was gavaged twice in the heart channel period (12:00) and pericardium channel period (20:00)], the Yangxin Tongmai Formula control group [18 g/(kg‧d) of Yangxin Tongmai Formula was gavaged twice at 8:00 and 18:00] and the Atorvastatin Calcium group [atorvastatin calcium tablets solution 1.8 mg/(kg‧d) at the same intervention time as that in Yangxin Tongmai Formula control group], and set up a blank group of 8 rats in each group. The model group and blank group were gavaged with 0.9% NaCl solution 4 ml/(kg‧d) for the same time as the Yangxin Tongmai Formula control group. After 3 weeks of gavage, the blood lipids [including total cholesterol (TC), low-density lipoprotein (LDL), high-density lipoprotein (HDL)] levels of rats in each group were detected; the HE staining of myocardial tissues and thoracic aorta was used to observe the pathomorphological changes; the levels of serum inflammation indexes [tumour necrosis factor alpha (TNF-alpha), lipopolysaccharide (LPS), and interleukin 10 (IL-10)] were detected; immunoprecipitation-realtime fluorescence quantitative PCR was used to detect the relative expression of cardiac tissue screening differential genes. ResultsThe genes screened for differentially methylated regions were calmodulin 2 (Calm2), calcium voltage-gated channel subunit α1s (Cacna1s), and phospholipase Cβ1 (Plcb1). Compared with the blank group, rats in the model group showed elevated levels of TC, LDL, TNF-α and LPS, and decreased levels of HDL and IL-10 (P<0.05 or P<0.01); HE staining showed obvious swelling of myocardial fibres, accompanied by a large number of inflammatory cell infiltration, and thickening of the inner wall of the aortic vessels with internal wall damage, which was visible as a large number of lipid cholesterol crystals and obvious inflammatory cell infiltration. Compared with the model group, the TC, LDL, TNF-α and LPS contents of rats in the Yangxin Tongmai Formula with midnight-noon ebb-flow administration method group, the Yangxin Tongmai Formula control group, and the atorvastatin calcium group all reduced, and the contents of HDL and IL-10 all elevated (P<0.05), with the improvement of myocardial tissue damage and the reduction of inflammatory infiltration, and the improvement of the damage of the inner lining of the thoracic aorta and the reduction of lipid infiltration. Compared with Yangxin Tongmai Formula control group, LDL, TNF-α and LPS contents reduced, and IL-10 contents increased in the midnight-noon ebb-flow administration method group (P<0.05). Compared with the model group, the relative expression of Calm2 and Plcb1 genes decreased and the relative expression of Cacna1s gene increased in Yangxin Tongmai Formula control group and the midnight-noon ebb-flow administration method group (P<0.05); compared with the Yangxin Tongmai Formula control group, the relative expression of Calm2 gene decreased and the relative expression of Cacna1s gene increased in the midnight-noon ebb-flow administration method group (P<0.05). ConclusionThe intervention of Yangxin Tongmai Formula in the heart channel period (12:00) and pericardium channel period (20:00) was more effective in improving the blood lipid level, inhibiting inflammation, and improving myocardial tissue damage in rats of PCHD with blood stasis syndrome, and Calm2 and Cacna1s genes may be the key targets of Yangxin Tongmai Formula in intervening the blood stasis syndrome of PCHD.
9.Determination of 238Pu,239Pu,240Pu and 241Pu in Soil by Tandem Quadrupole Inductively Coupled Plasmon-Mass Spectrometry
Yi-Chao GUO ; Chen-Yang PENG ; Xin-Yu DU ; Feng ZHANG ; Hao-Lin ZHOU ; Ke-Liang SHI ; Shan XING ; Xiao-Lin HOU
Chinese Journal of Analytical Chemistry 2025;53(3):397-406
Plutonium isotopes(238Pu,239Pu,240Pu and 241Pu)in the environment are important"fingerprint"nuclides in the study of nuclear activity traceability.The content of plutonium isotopes in the environmental metrics is usually very low,and the measurement of these isotopes,especially 238Pu,using mass spectrometry is seriously interfered with by the coexisting 238U.The analysis of several plutonium isotopes in soil usually requires combination of multiple measurement techniques,which leads to a long analysis time and large uncertainty in the isotope ratio.In this work,the hydrous titanium oxide(HTiO)precipitated by the hydrolysis of titanium oxydichloride(TiOCl2)under near-neutral condition was used to preconcentrate plutonium from the soil digestion solution,and the highly efficient decontamination of 238U in the sample was achieved by TK200 resin column chromatography with a decontamination factor of 108.Simulation resuts of density functional theory(DFT)showed that NH3 was considered as a promising reaction gas to eliminate the interference of 238U from 238Pu measurement using mass spectrometry due to the significant discrepancy of the chemical reactivity of U+and Pu+with the reactive gas NH3.Experiments confirmed that by optimizing the flow rates of collision gas(He)and reaction gas(NH3),the interference of 238U could be effectively suppressed,and the decontamination factor of 238U was 104.Combined with chemical separation,the overall decontamination factor of 238U could reach 1012 by using the developed method.By combining chemical separation and tandem quadrupole inductively coupled plasmon-mass spectrometry(ICP-MS/MS)measurement,the simultaneous determination of four ultra-trace plutonium isotopes in soil was realized,and the detection limit of plutonium isotopes was at the femtogram level.Analysis of the international standard reference materials(NIST-SRM-4357 and IAEA-384)showed that the established method could be successfully used for the accurate analysis of ultra-trace four plutonium isotopes(238Pu,239Pu,240Pu and 241Pu)in soil samples.
10.Constructing a model of degenerative scoliosis using finite element method:biomechanical analysis in etiology and treatment
Kai HE ; Wenhua XING ; Shengxiang LIU ; Xianming BAI ; Chen ZHOU ; Xu GAO ; Yu QIAO ; Qiang HE ; Zhiyu GAO ; Zhen GUO ; Aruhan BAO ; Chade LI
Chinese Journal of Tissue Engineering Research 2025;29(3):572-578
BACKGROUND:Degenerative scoliosis is defined as a condition that occurs in adulthood with a coronal cobb angle of the spine>10° accompanied by sagittal deformity and rotational subluxation,which often produces symptoms of spinal cord and nerve compression,such as lumbar pain,lower limb pain,numbness,weakness,and neurogenic claudication.The finite element method is a mechanical analysis technique for computer modelling,which can be used for spinal mechanics research by building digital models that can realistically restore the human spine model and design modifications. OBJECTIVE:To review the application of finite element method in the etiology and treatment of degenerative scoliosis. METHODS:The literature databases CNKI,PubMed,and Web of Science were searched for articles on the application of finite element method in degenerative scoliosis published before October 2023.Search terms were"finite element analysis,biomechanics,stress analysis,degenerative scoliosis,adult spinal deformity"in Chinese and English.Fifty-four papers were finally included. RESULTS AND CONCLUSION:(1)The biomechanical findings from the degenerative scoliosis model constructed using the finite element method were identical to those from the in vivo experimental studies,which proves that the finite element method has a high practical value in degenerative scoliosis.(2)The study of the etiology and treatment of degenerative scoliosis by the finite element method is conducive to the prevention of the occurrence of the scoliosis,slowing down the progress of the scoliosis,the development of a more appropriate treatment plan,the reduction of complications,and the promotion of the patients'surgical operation.(3)The finite element method has gradually evolved from a single bony structure to the inclusion of soft tissues such as muscle ligaments,and the small sample content is increasingly unable to meet the research needs.(4)The finite element method has much room for exploration in degenerative scoliosis.

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