1.Construction of a finite element model based on lunate sagittal Micro-CT images and its stress analysis
Chuanchao DU ; Ge XIONG ; Shuang REN ; Qiguo RONG ; Heng ZHANG
Chinese Journal of Tissue Engineering Research 2017;21(27):4385-4390
BACKGROUND: Biomechanical mechanisms are complex, and previous studiers focus on the stress conduction in the carpus. However, the stress distribution and characteristics of trabecula in the carpus are rarely reported.OBJECTIVE: To investigate the stress distribution and deformation characteristics of the normal lunate through a two-dimensional sagittal finite element model.METHODS: A normal cadaveric lunate sample was scanned with Micro-CT and the central sagittal image was chosen for further finite element analysis (FEA). The chosen image was processed and imported into the finite element analysis software (Ansys 14.0). A two-dimensional sagittal finite element model of the lunate bone was established. Axial pressure was applied to the model with the wrist held in different positions, and nine regions of interests (ROIs) were identified, for which stress and displacement nephograms were created. These included the first principal stress (S1, the maximum stress in a principal plane), the third principal stress (S3, the minimal stress in a principal plane), shear stress (SXY, the component of stress coplanar with a material cross section), von Mises stress (SEQV, yielding begins when the elastic energy of distortion reaches a critical value)and displacement of each ROI (UY, displacement on the vertical plane of the lunate) which were calculated and compared.RESULTS AND CONCLUSION: (1) The stresses on ROIs located in the proximal and volar cortices of the lunate bone were much higher than those in the distal and dorsal cortices. At the proximal lunate, S1 was less than S3; however at the distal lunate, S1 was greater than S3. The ROIs of the distal and proximal ends of the lunate bone received much higher stress than the ROIs of the middle part. As for axial trabecular displacement,both distal and proximal ROIs were compressed by axial pressure. However, the dorsal and the volar parts of the proximal lunate moved in different directions at different wrist postures. Besides, the stress values and magnitudes of displacement were elevated in wrist flexion and extension compared to neutral position.Furthermore, the stress concentration zones (the proximal volar ROI, the proximal dorsal ROI, the distal volar ROI, and the distal dorsal ROI) had different directions of shear stress and displacement in different wrist postures. (2) These results suggest that when stress is loaded on a normal lunate model, four stress concentration zones, the proximal volar ROI, the proximal dorsal ROI, the distal volar ROI, and the distal dorsal ROI are found. The wrist postures can significantly affect the value and distribution of axial stress on the sagittal lunate.
2.Effect of different doses of ultraviolet B on the proliferation of and autophagosome formation in keratinocytes
Dan HUANG ; Faliang REN ; Xu CHEN ; Kun CHEN ; Heng GU
Chinese Journal of Dermatology 2013;46(12):881-884
Objective To observe the changes in proliferative activity of and autophagosome formation in human HaCaT keratinocytes and primary keratinocytes after different doses of ultraviolet B (UVB) radiation,and to assess the potential relationship between proliferation impairment and autophagosome formation.Methods Both cultured HaCaT cells and primary keratinocytes from human foreskin were irradiated with different doses (5,10,20and 40 mJ/cm2) of UVB.Those receiving no irradiation served as the control.After additional 12-hour culture,methyl thiazolyl tetrazolium (MTT) assay was performed to evaluate the proliferative activity of cells,monodansylcadaverin (MDC) staining to detect autophagosomes in cells.The number of autophagosome-positive or negative cells was counted using inverted fluorescence microscopy.Results UVB radiation induced a significant decrease in the proliferation of keratinocytes,especially in that of HaCaT cells.The proliferative activity expressed as the absorbance value at 490 nm was significantly lower in HaCaT cells (1.367 ± 0.035,1.173 ± 0.034 and 0.873 ±0.025 vs.1.519 ± 0.022,all P< 0.01) and primary keratinocytes (0.782 ± 0.012,0.773 ± 0.021 and 0.725 ± 0.031 vs.0.887 ± 0.035,all P < 0.05) irradiated with UVB of 10,20 and 40 mJ/cm2 than in the unirradiated control cells.Significant differences were also observed in the proliferative activity among HaCaT cells irradiated with UVB of 10,20 and 40 mJ/cm2.The proportion of autophagosome-positive cells was increased after irradiation with UVB of 5,10 and 20 mJ/cm2,but decreased after irradiation with UVB of 40 mJ/cm2 in keratinocytes,especially in the primary keratinocytes.In detail,the proportion of autophagosome-positive cells was 22.69% ± 2.15%,28.10% ± 2.92% and 22.92% ± 2.61% in HaCaT cells irradiated with UVB of 10,20 and 40 mJ/cm2 respectively,significantly higher than that in the unirradiated cells (10.18% ± 1.50%,chi-square test for trends:x2 =27.48,P < 0.01).No significant changes were observed in the proportion of autophagosome-positive cells in primary keratinocytes after irradiation with UVB of 5,10 and 20 mJ/cm2,but a marked decrease was found after irradiation with UVB of 40 mJ/cm2 compared with unirradiated keratinocytes (chi-square test for trends:x2 =6.86,P < 0.01).Conclusions UVB radiation (10-40 mJ/cm2) decelerates the proliferation of HaCaT cells and primary keratinocytes in a dosedependent manner,and primary keratinocytes seem to be more resistant to UVB damage than HaCaT cells.Low to moderate doses (5-20 mJ/cm2) of UVB promote autophagosome formation in HaCaT cells in a dose-dependent manner,and exert no significant influence on that in primary keratinocytes; however,UVB of 40 mJ/cm2 suppresses autophagosome formation in keratinocytes,especially in primary keratinocytes.
3.Delicacy management practice of NSFC application process in an affiliated hospital of a medical university
Niannian LI ; Heng WANG ; Jiayun ZHAO ; Ren YE ; Mengming CHENG
Chinese Journal of Medical Science Research Management 2017;30(4):278-281
Objective summarize the delicacy management practices through the NSFC application procedures in a university affiliated hospital,to provide further reference for improvement of the NSFC project approvai ratio.Methods To summarize the management experiences by analyzing the approval number,project category and funds of NCFS from 2006 to 2015.Results The delicacy man agement practices include cultivate scientific research atmosphere by strengthen motivation,initiate application as early as possible,enlarging application number by extensive mobilization,improve applica tion quality by massive training,multi-round updates,tutorial,prevent avoidable errors by cross-over review.Conclusions Delicacy management by scientific research management department during the application process is critical to improve the project approval ratio of NCFS in a hospital.
4.Study on compatibility of Salviae Miltiorrhizae Radix et Rhizoma and Chuanxiong Rhizoma based on pharmacokinetics of effective components salvianolic acid B and ferulic acid in rat plasma.
Cui-ying ZHANG ; Hong ZHANG ; Yu DONG ; Wei-guang REN ; Heng-wen CHEN
China Journal of Chinese Materia Medica 2015;40(8):1589-1593
A study was made on the pharmacokinetic regularity of effective components salvianolic acid B and ferulic acid in Salviae Miltiorrhizae Radix et Rhizoma (SMRR) and Chuanxiong Rhizoma(CR) in rats, so as to discuss the compatibility mechanism of Salviae Miltiorrhizae Radix et Rhizoma and Chuanxiong Rhizoma. Rats were randomly divided into three groups and intravenously injected with 50 mg x kg(-1) salvianolic acid B for the single SMRR extracts group, 0.5 mg x kg(-1) ferulic acid for the single CR extracts group and 50 mg x kg(-1) salvianolic acid B + 0.5 mg x kg(-1) ferulic acid for the SMRR and CR combination group. The blood samples were collected at different time points and purified by liquid-liquid extraction with ethyl acetate. With chloramphenicol as internal standard (IS), UPLC was adopted to determine concentrations of salvianolic acid B and ferulic acid. The pharmacokinetic parameters of salvianolic acid B and ferulic acid were calculated with WinNonlin 6.2 software and analyzed by SPSS 19.0 statistical software. The UPLC analysis method was adopted to determine salvianolic acid B and ferulic acid in rat plasma, including linear equation, stability, repeatability, precision and recovery. The established sample processing and analysis methods were stable and reliable, with significant differences in major pharmacokinetic parameters, e.g., area under the curve (AUC), mean residence time (MRT) and terminal half-life (t(1/2)). According to the experimental results, the combined application of SMRR and CR can significantly impact the pharmacokinetic process of their effective components in rats and promote the wide distribution, shorten the action time and prolong the in vivo action time of salvianolic acid B and increase the blood drug concentration and accelerate the clearance of ferulic acid in vivo.
Animals
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Apiaceae
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chemistry
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Benzofurans
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blood
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pharmacokinetics
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Coumaric Acids
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blood
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pharmacology
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Drug Interactions
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Drugs, Chinese Herbal
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analysis
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pharmacokinetics
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Male
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Rats
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Rats, Sprague-Dawley
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Rhizome
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chemistry
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Salvia miltiorrhiza
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chemistry
5.Diagnosis and surgical treatment of intravenous tumor embolus extending through inferior vena cava into the right cardiac cavities
Guotao MA ; Qi MIAO ; Hua REN ; Xingrong LIU ; Chaoji ZHANG ; Heng ZHANG ; Lihua CAO
Basic & Clinical Medicine 2006;0(04):-
Objective Renal tumor and gynecological tumor invading into inferior vena cava and extending to the right cardiac cavities is quite uncommon,we report the experience of diagnosis and surgical treatment of intravenous tumor embolus extending through inferior vena cava into the right cardiac cavities.Methods From Junuary 2001 to May 2008,4 patients with intravenous tumor embolus extending through inferior vena cava into right cardiac cavity were treated in PUMC Hospital.Three cases were leiomyomatosis.Two patients' operation was performed by stages,firstly removed tumer in the right cardiac cavities using cardiopulmonary bypass under mid-hypothermia,and,postoperatively 3~4 weeks,total abdominal hysterectomy with bilateral salpingo-oophorectomy including the tumor mass was performed.The other patient's tumor was resected at one time.One case is renal clear cell carcinoma,The urologist performed abdominal nephrectomy and then cardiac surgeon resected tumor embolus using cardiopulmonary bypass under deep hypothermic total circulatory.Results The four patients were uneventful recovery,there was no death or any serious perioperative complications.Following up of 3 months to 4 years showed no tumor recurrence after the operation.Conclusion Confirmed diagnosis,the tumor embolus extending through inferior vena cava into the right cardiac cavities should be suspected among patients with renal cell carcinoma and multiple hysteromyoma are all critical for the treatment.Successful therapy for intravenous tumor embolus is dependent on totalone or two-stage surgical excision of the tumor and multi-department cooperation and combined therapy.
6.The influence of CTP-OD1-HA and CTP-OD2-HA fusion peptides or combine with imatinib on proliferation of K562 cells
Heng XIAO ; Yanbin REN ; Zhiming YANG ; Shujie ZHOU ; Lei YIN ; Zhimei QIN ; Ling XU ; Shouxia LI
International Journal of Laboratory Medicine 2017;38(14):1876-1878
Objective To study the influence of CTP-OD1-HA and CTP-OD2-HA fusion peptides and combined with imatinib on proliferation of K562 cells.Methods K562 cells were treated with CTP-OD1-HA and CTP-OD2-HA peptides or together with imatinib.The proliferation of cells were detected and compared by MTT and clone formation methods.Results MTT examination demonstrated that CTP-OD1-HA and CTP-OD2-HA peptides could inhibit the proliferation of K562 cells,and the effect was more obvious when acted along with imatinib;Clone formation showed that CTP-OD1-HA and CTP-OD2-HA peptides suppressed the continuous colony forming ability of K562 cells.Conclusion CTP-OD1-HA and CTP-OD2-HA could specially inhibit the proliferation of K562 cells,and increase the sensitivity of imatinib.
7.MRI features of the intervertebral suppurative spondylitis
Xiaofeng TANG ; Youkuan REN ; Heng MA ; Chengtao ZHOU ; Renqi MU ; Xiaoyuan SUN
Chinese Journal of Radiology 2008;42(7):688-691
Objective To explore MRI findings of intervertebral suppurative spondylitis. Methods MRI findings of intervertebral suppurative spondylitis in 12 cases proved by surgery and 6 cases defined by clinical features were retrospectively analyzed. The MRI protocol included un-enhanced conventional scan in 18 cases and contrast-enhanced scan in 11 cases. Results Of the 18 cases, single focus was found in 16 cases, and multiple loci were seen in 2 cases. MRI findings included (1) Disappearance sign of nuclear crevice in 17 cases, accumulated fluid sign of intervertebral disc in 15 cases, intervertebral disc perforation in 4 cases, and intervertebral space narrowing in 7 cases. (2) Bone destruction under end plate and marrow oedema were shown in 18 cases, 17 cases had end plate destruction, 16 cases had covered sign of end plate.(3) Paraspinal soft tissue swelling was shown in 18 cases, in which thick wall microabscess was formed in 4 cases. (4) Vertebral canal was involved in 12 cases, vertebral canal abscess was formed in 5 cases.(5) Lump enhancement was demonstrated in 4 cases, nodular enhancement in 2, and ring-like enhancement in 2, respectively. No enhancement was seen in 3 cases. Dural sac linear enhancement was shown in 6 cases, and patchy enhancement in the anterior dural sac was shown in 10 cases. Conclusion Intervertebral suppurative spondytitis had characteristic MRI findings, and the key to correct diagnosis was to combine MRI finding with clinical characteristics.
8.Progress of research on the proteomics of Bacillus anthracis
Jing-Xiao, REN ; Xian-Kai, LIU ; Fu-Sheng, CHEN ; Heng-Liang, WANG
Bulletin of The Academy of Military Medical Sciences 2009;33(6):583-585
Proteomics, which has been widely used in life science, is an emerging discipline following genomics. It can help to explore the pathogenic mechanism and early onset marker of Bacillus anthracis, playing an important part in the prevention, diagnosis and treatment of B.anthracis. In this paper,the application of proteomics in the research of B.anthracis is reviewed.
9.Investigation of thyroid function parameters in subclinical hypothyroid women treated with levothyroxine during pregnancy
Heng SU ; Xiulian REN ; Shan MA ; Hong CHEN ; Yuanming XUE ; Yun ZHANG ; Baosheng ZHU
Chinese Journal of Endocrinology and Metabolism 2012;(11):895-896
Subclinical hypothyroidism during pregnancy is associated with some adverse outcomes during maternal pregnancy.The present study investigated thyroid function parameters measured by electroehemiluminescence (ECL) immunoassays in subclinical hypothyroid women treated with levothyroxine (L-T4) during pregnancy.The results showed that in evaluating thyroid function with ECL immunoassays during replacement with L-T4,determination of serum TT4 appears to have a closer correlation with TSH and may better reflect the effìcacy of treatment.
10.Levothyroxine dosage and related factors in the treatment of pregnant women with subclinical hypothyroidism
Heng SU ; Xiulian REN ; Shan MA ; Hong CHEN ; Yuanming XUE ; Yun ZHANG ; Baosheng ZHU
Chinese Journal of Endocrinology and Metabolism 2012;28(10):826-829
Objective To study the levothyroxine doses and related factors in the treatment of pregnant women with subclinical hypothyroidism (SCH).Methods Fifty-six pregnant women with SCH (diagnosed before 12 weeks of gestation) were recruited and divided into 2 groups according to the baseline TSH levels,SCH group 1 (2.5 mIU/L ≤ TSH ≤ 5.0 mIU/L,n =24) and SCH group 2 (TSH>5.0 mIU/L,n =32).Thyroid autoantibodies [thyroid peroxidase antibody(TPOAb) and thyroglobulin antibody(TGAb)] were detected.All the subjects were treated with levothyroxine and the doses were adjusted according to the TSH level.The therapeutic target was to keep the TSH levels under control,0.3 to 2.5 mIU/L for the first trimester and 0.3 to 3.0 mIU/L for the second and third trimesters.Results There was a positive correlation between the levothyroxine doses and baseline TSH levels (r =0.533,P<0.01) in pregnant women with SCH.A significant difference in the levothyroxine doses between SCH group 1 and SCH group 2 was found [(0.583 ± 0.341) vs (0.961 ± 0.405) μg/kg,t =-3.695,P< 0.01].The levothyroxine doses in SCH group 2 were 64.84% higher than those in group 1.There was a significant difference in the levothyroxine doses between thyroid autoantibody negative and positive subjects [(0.680 ± 0.370) vs (0.918 ±0.440) μg/kg,t =-2.197,P =0.032].The levothyroxine doses in thyroid autoantibody positive subjects were 35 % higher than those in the negative subjects.In addition,there was a significant difference in the levothyroxine doses between subjects with negative and positive thyroid autoantibody [(0.421 ± 0.192) vs (0.720 ± 0.385)μg/kg,t =-2.331,P =0.029] in SCH group 1.While in SCH group 2,the difference did not reach statistical significance.Conclusion The baseline TSH levels and status of thyroid autoantibodies may affect the levothyroxine dosage in pregnant women with SCH.