Hypertensive vascular remodeling has always been a hot program in clinic and basic research.Renin-angiotensin system is an importent regulatory mechanism of human physiological function,which plays a fundamental role in vascular remodel- ing.RAS consists of two axes, ACE-AngII-AT_1 receptor axis and ACE2-Ang(1- 7)-Mas receptor axis.The former affects vasoconstriction and promotes vascular re-modeling through its key member,AngII;the latter offsets the effect of the mentioned AngII with the help of seven-peptide Ang-(1-7).A deep knowledge of the relation between RAS and vascular remodeling would provide more remedies for reducing cardiovascular risk.

Objective To investigate the stress characteristics of atlanto-axial bony structure under conditions of anteflexion,posterior extension,lateral flexion,and rotation after artificial atlanto-odontoid joint arthroplasty using three-dimensional finite element method and to improve the orientation of artificial atlantoodontoid joint from perspective of stress.Methods A three-dimensional finite element model of prosthetic atlanto-odontoid joint arthroplasty was created from CT images of the artificial atlantoodontoid joint and cervical vertebrae using software Mimics,Freeform,and Ansys.Stress characteristics of the model dealt with proneness,posterior extension,lateral flexion,or rotation loads were observed.Biomechanical performance of the bony structure of the model was analyzed and the orientation in improving the prosthesis was discussed.Results Anteflexion loading produced a maximum stress of 0.138 ×l08 N/m2 at the junction of lateral mass and posterior arch of the atlas,and 0.201 × 108 N/m2 at axial nail hole,contact point of plates with the axis,and posterior arch of the axis.Posterior extension loading produced a maximum stress of 0.666 × 107 N/m2 at junction of lateral mass and posterior arch of the atlas and 0.254 × 108 N/m2 at arch of the axis.Besides,stress concentration occurred at atlantoaxis nail hole.Right bending produced a maximum stress of 0.124 × 108 N/m2 at nail hole of right mass of atlas and 0.178 × 108 N/m2 at right contact point of the axis with plates.Right rotation produced a maximum stress of 0.847 × 107 N/m2 at junction of lateral mass and posterior arch of the atlas and 0.170 × 109 N/m2 at contact point of the axis with plates.The finite element model comprised 28 620 nodes and 107 441 units and provided good defining of the structural properties of artificial atlanto-odontoid joint arthroplasty.Under different loading conditions,the stress was mainly distributed in contact point of the vertebral body with plates,nail holes,junction of lateral mass and posterior arch of the atlas,and axial pedicle.Conclusions Prosthetic atlanto-odontoid joint scatters a part of the stress and alters the stress distribution of the atlas and axis from the intact condition.Finite element method can obtain complete analysis of the stress distribution of the artificial atlanto-odontoid joint arthroplasty.

Objective To study the ultrastructure of human oocytes cultured in vitro.Methods Ultrastructure of oocytes at different stages and of different quality were observed under transmission electron microscope(TEM).Immature oocytes at germinal vesicle(GV) stage and at MI stage after germinal vesicle break-down before and after being cultured in vitro,as well as mature oocytes at MⅡ stage after being cultured were evaluated according to their morphology under light microscope,and then studied by TEM. Results At GV stage the microvilli on oocyte surface were rare and shorter.Nucleus with a dense nucleolus was located in the periphery of oocyte.After culture the oocyte microvilli became denser and increased in number.There were rich ooplasm with organelles,such as large numbers of secretion vesicles,mitochondria and lipid droplets in the GV oocyte.The end of cumulus cell expanded and penetrated into the oocyte zone,forming gap junctions with oocyte microvilli.Functional connection of the adjacent cumulus cells was by desmosomes. In mature oocytes the rough endoplasmic reticulum and Golgi apparatus decreased while the smooth endoplasmic reticulum increased in number.Mitochondria degenerated and lipid droplets fused to form bigger ones.Cortical granules were distributed beneath the cytoplasm membrane in a line manner.The cell junctions between oocytes and cumulus cells were interrupted.There were various organelles in the first polar body.The mature oocytes with lower quality appeared to have lots of swollen mitochondria with blurred cristae and membrane.Some of these oocytes had fractured first polar bodies and deformed zona pellucida.Their surrounding cumulus cells showed higher frequency of cell apoptosis.Conclusion The ultrastructure of human oocytes at different stages and of different quality cultured in vitro was revealed.

BACKGROUND:Repairing tuberculosis bone defect has become a research focus with the development of anti-tuberculosis functional bone tissue engineering scaffold. OBJECTIVE:To evaluate the preparation, drug release performance and osteogenic properties of the anti-tuberculosis functional bone tissue engineering scaffold. METHODS:PubMed, Chinese Journal Ful-text Database, Wanfang databases were searched by computer for articles addressing functional bone tissue engineering scaffold for repair of tuberculosis bone defect. The keywords were“bone tissue engineering scaffold;tuberculosis;bone defect”in English and Chinese. RESULTS AND CONCLUSION:The anti-tuberculosis functional bone tissue engineering scaffold has good drug delivery, biocompatibility, osteogenic properties and anti-tuberculosis properties. As a good choice to avert bone defect relapse, the scaffold enables a long and stable drug release into bone defects to enhance the therapeutic efficacy of anti-tuberculosis drugs topical y. Given the technical deficiencies, we can only combine two drugs with the anti-tuberculosis bone tissue engineering scaffold, although the combined use of three or four anti-tuberculosis drugs is preferred. Additional y, a complete course of anti-tuberculosis treatment often lasts for 6-12 months, which cannot be achieved by the existing anti-tuberculosis bone tissue engineering scaffold. Up to now, the effect of this scaffold has not yet been confirmed in animal models, although how to prepare this scaffold has been reported.

Objective:To study the effects of different collagen conc en tration on the proliferation of rat fibroblasts.Methods: Fibrobl asts of 1-2 days new born SD rat from back skin were isolated and seeded into D MEM containing ?=10% fetal boven serum and collagen at the concentration (mg/ml ) of 6.4,5.3and 4.0 respectively. The status and numbers of fibroblasts were observed under light microscope and analysized using ttest. Results : The general condition of fibroblasts in 6.4 mg/ml collagen was better than that in the other groups. The processes of the cells were apparent, simila r to the status of the cells in two-dimensional culture. Vacuoles and granules in cells were observed in 5.3 mg/ml collagen. In 4 mg/ml collagen, the processe s of fibroblasts disappeared; the nuclei were karyopyknosis or dissolved. Some c ells was likely to be apoptotic. The average cell number per 200? field of micr oscope in 6.4,5.3 and 4.0 mg/ml collagen was 25,15 and 6 respectively (P

Objective To observe the expression level of inhibitor of differentiation 2 (Id‐2) and matrix metalloproteinases‐9 (MMP‐9) in rectal cancer ,analysis the correlation of the expression level of them ,to study the relationship between the expression level of them and the clinical pathology indicators of rectal cancer .Methods Rectal cancer tissues and normal tissue adjacent to rec‐tal cancer were obtained from the rectal cancer resection of 56 patients with rectal cancer ,using immunohistochemical method to ob‐serve the expression level of Id‐2 and MMP‐9 in normal tissue adjacent to rectal cancer and rectal cancer and Spearman correlation test to detect the correlation between the expression level of Id‐2 and MMP‐9 ;then we analyzed the relationships between the ex‐pression level of Id‐2 and MMP‐9 and the index of rectal cancer clinical pathology .Results The positive expression rate of Id‐2 in the in rectal cancer tissues is more higher than that of normal tissue of adjacent to rectal cancer (73 .21% vs .48 .21% ,P<0 .05) . The positive expression rate of MMP‐9 in the in rectal cancer tissues is higher than that of normal tissue of adjacent to rectal cancer (71 .43% vs .44 .64% ,P<0 .05) .Spearman correlation test showed that there is the positive correlation between the expression level of Id‐2 and MMP‐9 (r=0 .393 ,P=0 .003) .The expression levels of Id‐2 and MMP‐9 in rectal cancer were correlated with the degree of tumor differentiation ,TNM stage and lymph node metastasis (P<0 .05) ,but had no differences between the elements of age and sex (P>0 .05) .Conclusion There is a close relationship between the expression levels of Id‐2 and MMP‐9 in rectal cancer and the occurrence and development of rectal cancer .Rectal cancer with the higher Id‐2 expression level may be the ways to achieve tumor invasion and metastasis through MMP‐9 as a facilitator .

With the global aging, the incidence rate of HCC in the elderly population is gradually increasing , and thus it has become a global health issue.With reference to relevant literature, this article analyzes the clinical features of elderly HCC patients and reviews the current status of therapies and clinical outcomes .The review of clinical outcomes is mainly based on the comparison of therapeutic outcome between elderly and non -elderly HCC patients in many countries and regions in the world .This article points out that elderly HCC patients have their own clinical features, and since elderly HCC patients often have other diseases , such as diabetes, renal failure, and lung and cardiovascular diseases, there is an increase in the risk of treatment, but they often have positive treatment outcomes .With the deepening of research and the improvement of various treatment methods , the therapeutic outcome of elderly HCC patients will also be improved .Therefore,positive attitude and strategies should be adopted in the clinical treatment of elderly HCC patients .

Objective:To explore the impact of stress perception on depression and the potential mediating role of resilience in medical staff.Methods:A total of 606 medical staff were recruited and investigated by self-designed questionnaire, the perceived stress scale (PSS-10), the 10-item Connor-Davidson resilience scale (CD-RISC-10), and the patient health questionnaire-9 (PHQ-9) from February to March, 2020.SPSS 26.0 software was used to execute Pearson or Spearman correlation analysis, common method biases test, and multicollinearity test.Model 4 in PROCESS 3.2 macro program and Bootstrap method were used for mediating effects analysis.Results:There was a positive correlation between stress perception score(16.93±6.65) and depression score (5.00(2.00, 9.00))( r=0.551, P<0.01), and a negative correlation between stress perception score and resilience score (27.08±8.68) ( r=-0.285, P<0.01) among 606 medical staff.There was a negative correlation between resilience score and depression score ( r=-0.474, P<0.01). Mesometric effect examination showed that resilience played a partial mediating role in the relationship between stress perception and depression, and the mediating effect accounted for 10.87% of the total effect. Conclusion:Stress perception can directly or indirectly influence depression scores, and resilience partially mediates the relationship between stress perception and depression.Depression can be reduced clinically by reducing stress perception or enhancing the resilience of medical personnel.

To explore the guidance value of QT dispersion (QTd) and JT dispersion (JTd) for identifica‐tion of coronary heart disease (CHD) with blood stasis syndrome type .Methods : A total of 246 CHD patients of our hospital were divided into blood stasis block group (n＝71) ,Tanbixinyang group (TBXY group ,n＝42) ,liver and renal Yin deficiency group (LRYD group ,n＝44) ,Qi and Yin deficiency group (QYD group ,n＝45) and cardiac and renal Yang deficiency group (CRYD group ,n＝35) according to four diagnostic methods of Traditional Chinese Medicine (TCM).The QTd ,corrected QTd (QTcd) ,JTd and corrected JTd (JTcd) were observed in all groups , and their predictive value for blood stasis block were analyzed .Results : Compared with TBXY ,LRYD ,QYD and CRYD group ,there were significant rise in levels of QTd [ (72. 21 ± 16.48) ms ,(50.89 ± 12.77) ms ,(49. 17 ± 7.91) ms ,(62. 54 ± 12.80) msvs.(82.30 ± 19.05) ms] ,QTcd [(73.82 ± 18. 72) ms ,(51.41 ± 12.81) ms ,(51. 12 ± 9.73) ms ,(62.48 ± 13.35) msvs .(87. 75 ± 20. 72) ms] ,JTd [ (74. 54 ± 16.83) ms ,(52.18 ± 12. 68) ms ,(51. 50 ± 10. 78) ms ,(64.75 ± 12. 30) msvs.(89.43 ± 24.40 ) ms] and JTcd [ (75.14 ± 21. 05 ) ms ,(54. 93 ± 11.41 ) ms , (52.90 ± 10. 03) ms ,(65.26 ± 12. 72) msvs.(91. 98 ± 24. 22) ms] in blood stasis block group , P＝0. 001 all.Area under curve (AUC) of QTd ,QTcd ,JTd ,JTcd predicting CHD with blood stasis block was 0. 832 ,0. 861 ,0.856 and 0.854 respectively ,and optimal cutoff point was 70.77ms ,69.83ms ,77. 80ms and 77.51ms respectively .Conclu‐sion : QTd and JTd levels on ECG in CHD patients with blood stasis block type are significantly higher than other syndrome types , so they possess certain guidance value for CHD syndrome typing .

Objective To investigate the clinical features and laboratory results in a patient with late onset autosomal recessive spastic ataxia of Charlevoix-Saguenay ( ARSACS ) carrying novel SACS ( spastic ataxia of Charlevoix-Saguenay ) gene heterozygous mutations .Methods A 26-year-old Chinese man developed since the age of 13 a progressive weakness and stiffness of his bilateral lower limbs and gait unsteadiness.He had pyramidal tract sign in his bilateral lower limbs , cerebellar ataxia and sensory-motor polyneuropathy , with hyperelastica and swan neck-like deformities of the fingers , pes cavus and hammer toes.Funduscopy and optical coherence tomography , brain and cervical MRI , conduction velocity of peripheral nerve , motor evoked potentials , visual and brainstem auditory evoked potentials , ultrasound of peripheral nerve , hips and legs MRI , electronystagmography , and targeted capture and next generation sequencing were performed .Results Funduscopy and optical coherence tomography revealed thickening of the retinal nerve fiber layer with unclear margined optic disc .MRI revealed symmetrical linear hypointensity lesions in the pons on T 2 and T2 FLAIR weighted images , thickened bilateral cerebellar peduncles , and flattened and atrophied cervical and upper thoracic spinal cord .Nerve conduction studies showed sensory nerve action potentials were absent in four limbs , motor conduction velocity was slowed , amplitude of muscle response was significantly decreased in lower-limb nerves ( decreased by 80% -100%) but normal in upper-limb nerves.Central motor conduction time of motor evoked potential was prolonged .Targeted capture and next generation sequencing revealed novel SACS compound heterozygous mutations , c.12637 _12638delGA (p.Glu4213ArgFs*3) and c.11274_11276delAAC (p.Ile3758_Thr3759delinsMet) derived from each parent respectively , which were confirmed by Sanger sequencing analyses . Conclusions Recognizing ARSACS triad and its characteristics on fundus and brain MRI is helpful for correct diagnosis . Our findings expand the clinical and genetic spectrum of ARSACS .