1.Mechanism of Zuogui Pills in regulating bone metabolism through OXT/OXTR feed-forward loop based on theory of "all marrows dominated by brain".
Yan-Chen FENG ; Ya-Li LIU ; Xue DANG ; Lu SUN ; Jin-Yao LI ; Jia-Bin SONG ; Shun-Zhi YANG ; Fei-Xiang LIU
China Journal of Chinese Materia Medica 2025;50(10):2761-2768
Grounded in the theory of "all marrows dominated by brain", this study explored the therapeutic mechanism of Zuogui Pills in modulating the oxytocin(OXT)/oxytocin receptor(OXTR) feed-forward loop in the treatment of postmenopausal osteoporosis(PMOP). A PMOP rat model was established using ovariectomy, and 70 Sprague-Dawley female rats were randomly divided into the following groups: sham operation group, model group, estradiol group(17β-estradiol, 0.05 mg·kg~(-1)·d~(-1)), Zuogui Pills low, medium, and high dose groups(0.2, 0.4, 0.8 g·kg~(-1)·d~(-1), respectively), and an antagonist group(atosiban 0.9 mg·kg~(-1)·d~(-1) + 17β-estradiol 0.05 mg·kg~(-1)·d~(-1) + Zuogui Pills 0.4 g·kg~(-1)·d~(-1)). After 12 weeks of model establishment, treatment was administered by gavage once daily for another 12 weeks, followed by sample collection. Enzyme-linked immunosorbent assay(ELISA) was used to measure serum levels of estrogen(E_2), OXT, tartrate-resistant acid phosphatase(TRACP-5b), and bone alkaline phosphatase(BALP). Histopathological changes in the left distal femur were observed through hematoxylin and eosin(HE) staining. Micro-computed tomography(micro-CT) was used to analyze the microstructure of the right distal femur. Western blot was employed to detect the expression levels of OXTR, small GTP-binding protein Ras, Raf1 proto-oncogene(Raf1), mitogen-activated protein kinase kinase 1/2(MEK1/2), and extracellular signal-regulated kinase 1/2(ERK1/2), and their phosphorylated forms in tibial tissues. Compared with the model group, the Zuogui Pills medium and high dose groups showed significantly increased levels of E_2, OXT, and BALP, with a notable decrease in TRACP-5b levels. Morphologically, the trabeculae in the left distal femur were more tightly arranged. The fibrous structure in the right distal femur was significantly improved in the Zuogui Pills high dose group. Additionally, the expression of OXTR, Ras, p-Raf1, p-MEK1/2, and p-ERK1/2 proteins in tibial tissues was significantly increased. The therapeutic effect of the Zuogui Pills high dose group was partially inhibited when an OXTR antagonist was administered. These findings suggest that Zuogui Pills can regulate the OXT/OXTR feed-forward loop, activate the phosphorylation of the downstream Ras/Raf1/MEK/ERK signaling pathway, and ultimately improve bone mineral density, thereby exerting therapeutic effects in PMOP.
Animals
;
Rats, Sprague-Dawley
;
Rats
;
Female
;
Drugs, Chinese Herbal/administration & dosage*
;
Oxytocin/genetics*
;
Receptors, Oxytocin/genetics*
;
Humans
;
Osteoporosis, Postmenopausal/genetics*
;
Bone and Bones/drug effects*
;
Brain/drug effects*
;
Bone Marrow/drug effects*
2.Mechanism of Chaijin Jieyu Anshen Formula in regulating synaptic damage in nucleus accumbens neurons of rats with insomnia complicated with depression through TREM2/C1q axis.
Ying-Juan TANG ; Jia-Cheng DAI ; Song YANG ; Xiao-Shi YU ; Yao ZHANG ; Hai-Long SU ; Zhi-Yuan LIU ; Zi-Xuan XIANG ; Jun-Cheng LIU ; Hai-Xia HE ; Jian LIU ; Yuan-Shan HAN ; Yu-Hong WANG ; Man-Shu ZOU
China Journal of Chinese Materia Medica 2025;50(16):4538-4545
This study aims to investigate the effect of Chaijin Jieyu Anshen Formula on the neuroinflammation of rats with insomnia complicated with depression through the regulation of triggering receptor expressed on myeloid cells 2(TREM2)/complement protein C1q signaling pathway. Rats were randomly divided into a normal group, a model group, a positive drug group, as well as a high, medium, and low-dose groups of Chaijin Jieyu Anshen Formula, with 10 rats in each group. Except for the normal group, the other groups were injected with p-chlorophenylalanine and exposed to chronic unpredictable mild stress to establish the rat model of insomnia complicated with depression. The sucrose preference experiment, open field experiment, and water maze test were performed to evaluate the depression in rats. Enzyme-linked immunosorbent assay was employed to detect serum 5-hydroxytryptamine(5-HT), dopamine(DA), and norepinephrine(NE) levels. Hematoxylin and eosin staining and Nissl staining were used to observe the damage in nucleus accumbens neurons. Western blot and immunofluorescence were performed to detect TREM2, C1q, postsynaptic density 95(PSD-95), and synaptophysin 1(SYN1) expressions in rat nucleus accumbens, respectively. Golgi-Cox staining was utilized to observe the synaptic spine density of nucleus accumbens neurons. The results show that, compared with the model group, Chaijin Jieyu Anshen Formula can significantly increase the sucrose preference as well as the distance and number of voluntary activities, shorten the immobility time in forced swimming test and the successful incubation period of positioning navigation, and prolong the stay time of space exploration in the target quadrant test. The serum 5-HT, DA, and NE contents in the model group are significantly lower than those in the normal group, with the above contents significantly increased after the intervention of Chaijin Jieyu Anshen Formula. In addition, Chaijin Jieyu Anshen Formula can alleviate pathological damages such as swelling and loose arrangement of tissue cells in the nucleus accumbens, while increasing the Nissl body numbers. Chaijin Jieyu Anshen Formula can improve synaptic damage in the nucleus accumbens and increase the synaptic spine density. Compared to the normal group, the expression of C1q protein was significantly higher in the model group, while the expression of TREM2 protein was significantly lower. Compared to the model group, the intervention with Chaijin Jieyu Anshen Formula significantly downregulated the expression of C1q protein and significantly upregulated the expression of TREM2. Compared with the model group, the PSD-95 and SYN1 fluorescence intensity is significantly increased in the groups receiving different doses of Chaijin Jieyu Anshen Formula. In summary, Chaijin Jieyu Anshen Formula can reduce the C1q protein expression, relieve the TREM2 inhibition, and promote the synapse-related proteins PSD-95 and SNY1 expression. Chaijin Jieyu Anshen Formula improves synaptic injury of the nucleus accumbens neurons, thereby treating insomnia complicated with depression.
Animals
;
Male
;
Rats
;
Nucleus Accumbens/metabolism*
;
Drugs, Chinese Herbal/administration & dosage*
;
Depression/complications*
;
Membrane Glycoproteins/genetics*
;
Rats, Sprague-Dawley
;
Sleep Initiation and Maintenance Disorders/complications*
;
Neurons/metabolism*
;
Receptors, Immunologic/genetics*
;
Signal Transduction/drug effects*
;
Synapses/metabolism*
3.Clinical efficacy of minimally invasive tendon blade technique in the treatment of moderate and severe gluteal muscle contracture.
Jia-Kai GAO ; Tao-Ran WANG ; Long BI ; Xiao-Chao CHEN ; Yan-Wu LIU ; Yao-Ping WU ; Xiang HE ; Zhi-Xia NIU
China Journal of Orthopaedics and Traumatology 2025;38(4):420-423
OBJECTIVE:
To investigate the clinical effect of minimally invasive technique in the treatment of moderate and severe gluteal muscle contracture.
METHODS:
A retrospective study was conducted on 85 patients (170 sides) with bilateral gluteal muscle contracture admitted from January 2016 to December 2019. All patients were treated with minimally invasive release of tendon knife. There were 32 males and 53 females, ranging in age from 15 to 37 years old, with an average age of (22.3±6.3) years old. Operation time, intraoperative blood loss, incision length, first postoperative ambulation time, complication rate, recurrence rate, and Harris hip score (HHS) were analyzed and evaluated.
RESULTS:
The average follow-up time was (16.2±4.6) months, ranging from 12 to 30 months. The operation time ranged from 7 to 15 min, with an average of (10.2±3.1) min. Intraoperative blood loss ranged from 2 to 20 ml, with an average of (8.4±2.2) ml. The incision length ranged from 0.6 to 2.0 cm, with an average of (0.8±0.3) cm. The time to postoperative ambulation ranged from 12 to 28 h, with an average of (20.0±3.2) h. All patients achieved primary wound healing without sciatic nerve injury or recurrence. HHS hip function scores ranged from 90 to 98, with an average score of (96.2±1.4). Complications included intraoperative tendon blade tip fracture in two cases (removed under fluoroscopic guidance) and subcutaneous hematoma in three cases-two resolved with compression and one with open evacuation.. Twenty-nine patients exhibited transient swaying gait postoperatively, of which 24 patients returned to normal after 4 weeks and 5 patients returned to normal after 6 weeks.
CONCLUSION
Minimally invasive tendon blade release is a safe and effective technique for treating gluteal muscle contracture, offering minimal trauma, rapid recovery, and excellent cosmetic and functional outcomes. However, it exhibits a low risk of blade tip fracture and sciatic nerve injury, warranting experienced surgical handling.
Humans
;
Male
;
Female
;
Adult
;
Minimally Invasive Surgical Procedures/methods*
;
Adolescent
;
Retrospective Studies
;
Buttocks/surgery*
;
Young Adult
;
Contracture/surgery*
;
Tendons/surgery*
;
Muscle, Skeletal/surgery*
4.Protective effect of sub-hypothermic mechanical perfusion combined with membrane lung oxygenation on a yorkshire model of brain injury after traumatic blood loss.
Xiang-Yu SONG ; Yang-Hui DONG ; Zhi-Bo JIA ; Lei-Jia CHEN ; Meng-Yi CUI ; Yan-Jun GUAN ; Bo-Yao YANG ; Si-Ce WANG ; Sheng-Feng CHEN ; Peng-Kai LI ; Heng CHEN ; Hao-Chen ZUO ; Zhan-Cheng YANG ; Wen-Jing XU ; Ya-Qun ZHAO ; Jiang PENG
Chinese Journal of Traumatology 2025;28(6):469-476
PURPOSE:
To investigate the protective effect of sub-hypothermic mechanical perfusion combined with membrane lung oxygenation on ischemic hypoxic injury of yorkshire brain tissue caused by traumatic blood loss.
METHODS:
This article performed a random controlled trial. Brain tissue of 7 yorkshire was selected and divided into the sub-low temperature anterograde machine perfusion group (n = 4) and the blank control group (n = 3) using the random number table method. A yorkshire model of brain tissue injury induced by traumatic blood loss was established. Firstly, the perfusion temperature and blood oxygen saturation were monitored in real-time during the perfusion process. The number of red blood cells, hemoglobin content, NA+, K+, and Ca2+ ions concentrations and pH of the perfusate were detected. Following perfusion, we specifically examined the parietal lobe to assess its water content. The prefrontal cortex and hippocampus were then dissected for histological evaluation, allowing us to investigate potential regional differences in tissue injury. The blank control group was sampled directly before perfusion. All statistical analyses and graphs were performed using GraphPad Prism 8.0 Student t-test. All tests were two-sided, and p value of less than 0.05 was considered to indicate statistical significance.
RESULTS:
The contents of red blood cells and hemoglobin during perfusion were maintained at normal levels but more red blood cells were destroyed 3 h after the perfusion. The blood oxygen saturation of the perfusion group was maintained at 95% - 98%. NA+ and K+ concentrations were normal most of the time during perfusion but increased significantly at about 4 h. The Ca2+ concentration remained within the normal range at each period. Glucose levels were slightly higher than the baseline level. The pH of the perfusion solution was slightly lower at the beginning of perfusion, and then gradually increased to the normal level. The water content of brain tissue in the sub-low and docile perfusion group was 78.95% ± 0.39%, which was significantly higher than that in the control group (75.27% ± 0.55%, t = 10.49, p < 0.001), and the difference was statistically significant. Compared with the blank control group, the structure and morphology of pyramidal neurons in the prefrontal cortex and CA1 region of the hippocampal gyrus were similar, and their integrity was better. The structural integrity of granulosa neurons was destroyed and cell edema increased in the perfusion group compared with the blank control group. Immunofluorescence staining for glail fibrillary acidic protein and Iba1, markers of glial cells, revealed well-preserved cell structures in the perfusion group. While there were indications of abnormal cellular activity, the analysis showed no significant difference in axon thickness or integrity compared to the 1-h blank control group.
CONCLUSIONS
Mild hypothermic machine perfusion can improve ischemia and hypoxia injury of yorkshire brain tissue caused by traumatic blood loss and delay the necrosis and apoptosis of yorkshire brain tissue by continuous oxygen supply, maintaining ion homeostasis and reducing tissue metabolism level.
Animals
;
Perfusion/methods*
;
Disease Models, Animal
;
Brain Injuries/etiology*
;
Swine
;
Male
;
Hypothermia, Induced/methods*
5.Novel biallelic MCMDC2 variants were associated with meiotic arrest and nonobstructive azoospermia.
Hao-Wei BAI ; Na LI ; Yu-Xiang ZHANG ; Jia-Qiang LUO ; Ru-Hui TIAN ; Peng LI ; Yu-Hua HUANG ; Fu-Rong BAI ; Cun-Zhong DENG ; Fu-Jun ZHAO ; Ren MO ; Ning CHI ; Yu-Chuan ZHOU ; Zheng LI ; Chen-Cheng YAO ; Er-Lei ZHI
Asian Journal of Andrology 2025;27(2):268-275
Nonobstructive azoospermia (NOA), one of the most severe types of male infertility, etiology often remains unclear in most cases. Therefore, this study aimed to detect four biallelic detrimental variants (0.5%) in the minichromosome maintenance domain containing 2 ( MCMDC2 ) genes in 768 NOA patients by whole-exome sequencing (WES). Hematoxylin and eosin (H&E) demonstrated that MCMDC2 deleterious variants caused meiotic arrest in three patients (c.1360G>T, c.1956G>T, and c.685C>T) and hypospermatogenesis in one patient (c.94G>T), as further confirmed through immunofluorescence (IF) staining. The single-cell RNA sequencing data indicated that MCMDC2 was substantially expressed during spermatogenesis. The variants were confirmed as deleterious and responsible for patient infertility through bioinformatics and in vitro experimental analyses. The results revealed four MCMDC2 variants related to NOA, which contributes to the current perception of the function of MCMDC2 in male fertility and presents new perspectives on the genetic etiology of NOA.
Humans
;
Male
;
Azoospermia/genetics*
;
Meiosis/genetics*
;
Spermatogenesis/genetics*
;
Adult
;
Exome Sequencing
;
Microtubule-Associated Proteins/genetics*
;
Alleles
;
Infertility, Male/genetics*
6.Mediating effect of sleep duration between depression symptoms and myopia in middle school students.
Wei DU ; Xu-Xiang YANG ; Ru-Shuang ZENG ; Chun-Yao ZHAO ; Zhi-Peng XIANG ; Yuan-Chun LI ; Jie-Song WANG ; Xiao-Hong SU ; Xiao LU ; Yu LI ; Jing WEN ; Dang HAN ; Qun DU ; Jia HE
Chinese Journal of Contemporary Pediatrics 2025;27(3):359-365
OBJECTIVES:
To explore the mediating role of sleep duration in the relationship between depression symptoms and myopia among middle school students.
METHODS:
This study was a cross-sectional research conducted using a stratified cluster random sampling method. A total of 1 728 middle school students were selected from two junior high schools and two senior high schools in certain urban areas and farms of the Xinjiang Production and Construction Corps. Questionnaire surveys and vision tests were conducted among the students. Spearman analysis was used to analyze the correlation between depression symptoms, sleep duration, and myopia. The Bootstrap method was employed to investigate the mediating effect of sleep duration between depression symptoms and myopia.
RESULTS:
The prevalence of myopia in the overall population was 74.02% (1 279/1 728), with an average sleep duration of (7.6±1.0) hours. The rate of insufficient sleep was 83.62% (1 445/1 728), and the proportion of students exhibiting depression symptoms was 25.29% (437/1 728). Correlation analysis showed significant negative correlations between visual acuity in both eyes and sleep duration with depressive emotions as measured by the Center for Epidemiologic Studies Depression Scale (with correlation coefficients of -0.064, -0.084, and -0.199 respectively; P<0.01), as well as with somatic symptoms and activities (with correlation coefficients of -0.104, -0.124, and -0.233 respectively; P<0.01) and interpersonal relationships (with correlation coefficients of -0.052, -0.059, and -0.071 respectively; P<0.05). The correlation coefficients for left and right eye visual acuity and sleep duration were 0.206 and 0.211 respectively (P<0.001). Sleep duration exhibited a mediating effect between depression symptoms and myopia (indirect effect=0.056, 95%CI: 0.029-0.088), with the mediating effect value for females (indirect effect=0.066, 95%CI: 0.024-0.119) being higher than that for males (indirect effect=0.042, 95%CI: 0.011-0.081).
CONCLUSIONS
Sleep duration serves as a partial mediator between depression symptoms and myopia in middle school students.
Humans
;
Myopia/etiology*
;
Male
;
Female
;
Depression/physiopathology*
;
Cross-Sectional Studies
;
Sleep
;
Adolescent
;
Students
;
Child
;
Time Factors
;
Sleep Duration
7.Serum Lipidomics Profiling to Identify Potential Biomarkers of Ischemic Stroke: A Pilot Study in Chinese Adults.
Ji Jun SHI ; Zu Jiao NIE ; Shu Yao WANG ; Hao ZHANG ; Xin Wei LI ; Jia Ling YAO ; Yi Bing JIN ; Xiang Dong YANG ; Xue Yang ZHANG ; Ming Zhi ZHANG ; Hao PENG
Biomedical and Environmental Sciences 2025;38(8):918-925
OBJECTIVE:
Lipid oxidation is involved in the pathogenesis of atherosclerosis and may be contribute to the development of Ischemic stroke (IS). However, the lipid profiles associated with IS have been poorly studied. We conducted a pilot study to identify potential IS-related lipid molecules and pathways using lipidomic profiling.
METHODS:
Serum lipidomic profiling was performed using LC-MS in 20 patients with IS and 20 age- and sex-matched healthy controls. Univariate and multivariate analyses were simultaneously performed to identify the differential lipids. Multiple testing was controlled for using a false discovery rate (FDR) approach. Enrichment analysis was performed using MetaboAnalyst software.
RESULTS:
Based on the 294 lipids assayed, principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) models were used to distinguish patients with IS from healthy controls. Fifty-six differential lipids were identified with an FDR-adjusted P less than 0.05 and variable influences in projection (VIP) greater than 1.0. These lipids were significantly enriched in glycerophospholipid metabolism (FDR-adjusted P = 0.009, impact score = 0.216).
CONCLUSIONS
Serum lipid profiles differed significantly between patients with IS and healthy controls. Thus, glycerophospholipid metabolism may be involved in the development of IS. These results provide initial evidence that lipid molecules and their related metabolites may serve as new biomarkers and potential therapeutic targets for IS.
Humans
;
Pilot Projects
;
Lipidomics
;
Male
;
Female
;
Biomarkers/blood*
;
Middle Aged
;
Ischemic Stroke/blood*
;
Aged
;
China
;
Lipids/blood*
;
Adult
;
Case-Control Studies
;
East Asian People
8.Based on supramolecular chemistry to explore the scientific connotation of the compatibility between licorice and the insoluble mineral medicine gypsum
Yao-zhi ZHANG ; Wen-min PI ; Lin-ying WU ; Lu-ping YANG ; Shu-chang YAO ; Xiang ZHANG ; Xue-mei HUANG ; Peng-long WANG
Acta Pharmaceutica Sinica 2024;59(4):1048-1056
Licorice-gypsum (gancao-shigao, GC-SG) drug pair was used as the research object, using supramolecular chemistry to explore the scientific connotation of combining herbal medicine GC with insoluble mineral medicine SG in clinical application of traditional Chinese medicine. ① The Tyndall effect, microscopic morphology and particle size of the single and co-decocted of GC and SG were observed, the paste content and conductivity were determined, and the interaction between GC and SG was detected by isothermal titration calorimetry (ITC) and infrared absorption spectroscopy (IR). ② Calcium chloride (CaCl2), a soluble calcium salt of equal gypsum quality, was used instead of SG with GC for co-decocting to explore the effect of calcium salt content on the water decocting, and the characteristics were combined with the Tyndall effect, microscopic morphology, paste content and conductivity. ITC and IR techniques were used to detect the interaction between the two, and the interaction between them was detected by ITC and IR. The zeta potential and ultraviolet-visible spectrophotometry (UV-vis) of GC-SG and GC-CaCl2 co-decoction were compared, and the inorganic and organic components in the co-decoction were detected by inductively coupled plasma optical emission spectrometer (ICP-OES) and high performance liquid chromatography (HPLC). The results showed: ① Compared with the liquid phase of single decoction, GC-SG co-decoction had more obvious Tyndall effect, and showed uniform spherical nanoparticles under electron microscope. Physical characterization results such as paste content and conductivity showed that co-decoction promoted the dissolution of each other's components; ITC and IR results showed that there was strong interaction between GC and SG, which preliminatively indicated that GC and SG co-decoction promoted the formation of uniform and stable supramolecular system of traditional Chinese medicine. ② When soluble calcium salt was used to substitute insoluble SG with GC for co-decocting, a stronger but astigmatic light path appeared than single decocting solution, the zeta potential was reduced, and a large number of accumulated polymers were formed. The results of paste content and conductivity showed that the dissolution of the co-decocting component was reduced than the single decocting component. ITC, UV-vis and IR results showed that there was interaction between GC with Ca2+ and SG. The formation of polysink indicated that a large amount of soluble calcium salt would destroy the stability of supramolecular Chinese medicine. The results of ICP-OES and HPLC showed that the glycyrrhizic acid (GA) content of the former lower than the latter, which was related to the formation of a large number of polycondensates with the increase of Ca2+ concentration and the decrease of the dissolution of GA and other active ingredients. This study indicates that the compatibility of GC and SG can form a uniform and stable supramolecular system of traditional Chinese medicine. Calcium salt, the main component of SG, is taken as the starting point. Excessive soluble Ca2+ can promote the aggregation of active ingredients such as GA, so as to reveal the scientific connotation of the compatibility of GC and SG, an insoluble mineral medicine.
9.Study on the preservation effects of the amputated forelimb by machine perfusion at physiological temperature
Sheng-Feng CHEN ; Bo-Yao YANG ; Tie-Yuan ZHANG ; Xiang-Yu SONG ; Zhi-Bo JIA ; Lei-Jia CHEN ; Meng-Yi CUI ; Wen-Jing XU ; Jiang PENG
Chinese Journal of Traumatology 2024;27(2):114-120
Purpose::Ischemia and hypoxia are the main factors limiting limb replantation and transplantation. Static cold storage (SCS), a common preservation method for tissues and organs, can only prolong limb ischemia time to 4 - 6 h. The normothermic machine perfusion (NMP) is a promising method for the preservation of tissues and organs, which can extend the preservation time in vitro by providing continuous oxygen and nutrients. This study aimed to evaluate the difference in the efficacy of the 2 limb preservation methods. Methods::The 6 forelimbs from beagle dogs were divided into 2 groups. In the SCS group ( n = 3), the limbs were preserved in a sterile refrigerator at 4 °C for 24 h, and in the NMP group ( n = 3), the perfusate prepared with autologous blood was used for the oxygenated machine perfusion at physiological temperature for 24 h, and the solution was changed every 6 h. The effects of limb storage were evaluated by weight gain, perfusate biochemical analysis, enzyme-linked immunosorbent assay, and histological analysis. All statistical analyses and graphs were performed using GraphPad Prism 9.0 one-way or two-way analysis of variance. The p value of less than 0.05 was considered to indicate statistical significance. Results::In the NMP group, the weight gained percentage was 11.72% ± 4.06%; the hypoxia-inducible factor-1α contents showed no significant changes; the shape of muscle fibers was normal; the gap between muscle fibers slightly increased, showing the intercellular distance of (30.19 ± 2.83) μm; and the vascular α-smooth muscle actin (α-SMA) contents were lower than those in the normal blood vessels. The creatine kinase level in the perfusate of the NMP group increased from the beginning of perfusion, decreased after each perfusate change, and remained stable at the end of perfusion showing a peak level of 4097.6 U/L. The lactate dehydrogenase level of the NMP group increased near the end of perfusion and reached the peak level of 374.4 U/L. In the SCS group, the percentage of weight gain was 0.18% ± 0.10%, and the contents of hypoxia-inducible factor-1α increased gradually and reached the maximum level of (164.85 ± 20.75) pg/mL at the end of the experiment. The muscle fibers lost their normal shape and the gap between muscle fibers increased, showing an intercellular distance of (41.66 ± 5.38) μm. The contents of vascular α-SMA were much lower in the SCS group as compared to normal blood vessels.Conclusions::NMP caused lesser muscle damage and contained more vascular α-SMA as compared to SCS. This study demonstrated that NMP of the amputated limb with perfusate solution based on autologous blood could maintain the physiological activities of the limb for at least 24 h.
10.Prediction of Wind Turbine Lubricating Oil's Acid Value by Ordinary Least Square Method Based on Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy Through Higher-Order Derivative Combined with Angular Metric
Chun-Hui GE ; Yan-Jun LIU ; Meng-Shi CHEN ; Ce YANG ; Pei-Pei LIANG ; Zhi-Xiang YAO ; Kai ZHANG
Chinese Journal of Analytical Chemistry 2024;52(9):1254-1265,中插1-中插4
To address the key challenges in multivariate statistical modeling,a higher-order derivative approach combined with vector space angle multiplicative error correction was proposed for establishing an acid value prediction ordinary least squares(OLS)regression model based on attenuated total reflectance-Fourier transform infrared(ATR-FTIR)spectroscopy.By using acid values measured by potentiometric titration as reference,ATR-FTIR spectroscopy was utilized for direct calibration and prediction of acid values on 96 kinds of lubricating oil samples from a wind turbine.Firstly,the simulated hyperbolic(SH)method was employed to obtain accurate fourth derivative spectrum,resolving overlapping bands and enhancing spectral selectivity.Then,from the calibration set(48 samples),informative spectral regions were identified based on correlation coefficients.Next,the sample with the highest acid value was selected as the reference and1/(1+tan(θ/2))was used as the metric relation of the spectrum to suppress the multiplicity error caused by factors such as the change of effective optical path in ATR-FTIR spectroscopy.After pretreatment of the spectrum by the method of fourth-order derivative combined with angular quantity,the number of variables decreased from 1737 to 8,and the matrix condition number decreased from 1.85×1015 to 56.34,which effectively eliminated the collinearity issue for OLS regression.Direct OLS modeling on spectral preprocessed data achieved a determination coefficient of 0.981 for 47 validation samples,with a relative error range of-8.38%-8.22%,outperforming the commonly used partial least squares(PLS)method(Determination coefficient of 0.865,relative error of-27.82%-22.38%).It was proved that effective data preprocessing significantly improved the prediction accuracy of the model.Furthermore,when the number of calibration set was compressed to 25 and the number of validation set was expanded to 70,the model retained 8 variables with a condition number of 42.60,the determination coefficient of validation set was 0.972,and the relative error ranged from-10.80%to 12.31%.Comparing with the PLS method(Determination coefficient of 0.724,relative error of-34.26%-53.84%),the improvement was more obvious,which showed that the method could still have high prediction accuracy even with fewer modeling samples as well as robustness against multiplicative error interference.

Result Analysis
Print
Save
E-mail