Objective:To measure and analyse maxillofacial skeletal morphology based on the 3D model by Mimics and Matlab soft-ware.Methods:140 male volunteers aged 18-37 years,99 of Han,32 of Uygur and 9 of other natinalities were included.The values of maxillofacial skeletal morphology were measured by Mimics software combined with Matlab software after CT scanning.The data of skeletal morphologic features among skeletal classⅠ,Ⅱ and Ⅲ and among the ethnic groups were analysed with SPSS 26.0 software.Results:The distribution of skeletal class showed that there were 83 cases(59.3％)of class Ⅰ,41(29.3％)of class Ⅱ and 16(11％)of class Ⅲ.There were no significant differences on the age,height,nasal bone length,nasal bone depth,maxillary width,maxillary height,mandibular symphysis height,condylion distance and gonion distance among the 3 skeletal groups(P＞0.05).Skeletal class Ⅱshowed a significant shorter mandibular ramus,mandibular body and entire mandibular length compared with class Ⅰ and class Ⅲ,while class Ⅱ had a significant longer palatal length and larger Me angle compared with class Ⅲ(P＜0.05).Skeletal class Ⅲ showed no significance differences of all dimensions compared with class Ⅰ(P＞0.05).The nasal bone depth of Han subjects was smaller than that of Uygur,while the length of the mandibular symphysis and the entire mandible of Han group were greater than that of Uygur group(P＜0.05).No correlation was observed between age and all facial skeletal dimensions respectively(P＞0.05).The ANB an-gle is negatively correlated with the mandibular body(r=-0.327)and mandibular length(r=-0.322)respectively.Conclusion:There was no significant difference in nasal bone,facial bone width and facial bone height among the 3 skeletal patterns.Class Ⅱhas a significant shorter mandibular ramus,mandibular body and entire mandibular length.Uygur young males have significantly greater nasal bone depth than Han.

Objective:To measure and analyse maxillofacial skeletal morphology based on the 3D model by Mimics and Matlab soft-ware.Methods:140 male volunteers aged 18-37 years,99 of Han,32 of Uygur and 9 of other natinalities were included.The values of maxillofacial skeletal morphology were measured by Mimics software combined with Matlab software after CT scanning.The data of skeletal morphologic features among skeletal classⅠ,Ⅱ and Ⅲ and among the ethnic groups were analysed with SPSS 26.0 software.Results:The distribution of skeletal class showed that there were 83 cases(59.3％)of class Ⅰ,41(29.3％)of class Ⅱ and 16(11％)of class Ⅲ.There were no significant differences on the age,height,nasal bone length,nasal bone depth,maxillary width,maxillary height,mandibular symphysis height,condylion distance and gonion distance among the 3 skeletal groups(P＞0.05).Skeletal class Ⅱshowed a significant shorter mandibular ramus,mandibular body and entire mandibular length compared with class Ⅰ and class Ⅲ,while class Ⅱ had a significant longer palatal length and larger Me angle compared with class Ⅲ(P＜0.05).Skeletal class Ⅲ showed no significance differences of all dimensions compared with class Ⅰ(P＞0.05).The nasal bone depth of Han subjects was smaller than that of Uygur,while the length of the mandibular symphysis and the entire mandible of Han group were greater than that of Uygur group(P＜0.05).No correlation was observed between age and all facial skeletal dimensions respectively(P＞0.05).The ANB an-gle is negatively correlated with the mandibular body(r=-0.327)and mandibular length(r=-0.322)respectively.Conclusion:There was no significant difference in nasal bone,facial bone width and facial bone height among the 3 skeletal patterns.Class Ⅱhas a significant shorter mandibular ramus,mandibular body and entire mandibular length.Uygur young males have significantly greater nasal bone depth than Han.

Objective To investigate the effects of microgravity environment on hibernating myoblasts.Methods Hibernating myoblasts were cultured under real and simulated microgravity conditions for 10 days.RNA-seq analysis and immunofluorescence are used to analysis the impact of microgravity environment on cell growth and gene expression of myoblasts.Results Under the microgravity conditions,genes associated with proliferation were upregulated.Under simulated microgravity,there were more and higher proportion of Ki67 positive cells compared to normal gravity conditions.Conclusion The microgravity environment promotes the proliferation of hibernating myoblasts.

Poly(dimethyl siloxane)(PDMS)is suitable for the fabrication of space cell culture chips.It is necessary to perform highly stable hydrophilic modification to promote cell adhesion on PDMS surface.We modified PDMS surface by oxygen plasma treatment combining with physical adsorption in this article.PDMS,which was treated with oxygen plasma and sequentially coated with Poly-L-lysine or collagen(PLL-ox-PDMS,COL-ox-PDMS)with various solution concentration and kept in different environmental conditions,were characterized by contact angle and surface energy measurements,and atomic force microscopy(AFM).Cell growth conditions on bare PDMS and modified PDMS were compared,and the numbers of live cells cultured for 1-3 days were evaluated.Experimental results indicate that higher solution concentration and low storage temperature benefit the hydrophilicity stability.The contact angles of PLL-ox-PDMS stored in 4℃and COL-ox-PDMS were close to 60°and 65°on day 25 and 14,respectively.Both modified PDMS surfaces are suitable for cell adhesion and proliferation,and no cell layer falls offin 10 days.The modification method is especially suitable for applications such as medium and long term space cell culture.

Apolipoprotein A-I (ApoA-I), the main protein component of high-density lipoprotein (HDL), plays a pivotal role in reverse cholesterol transport (RCT). Previous studies indicated a reduction of serum ApoA-I levels in various types of cancer, suggesting ApoA-I as a potential cancer biomarker. Herein, ectopically overexpressed ApoA-I in MDA-MB-231 breast cancer cells was observed to have antitumor effects, inhibiting cell proliferation and migration. Subsequent studies on the mechanism of expression regulation revealed that estradiol (E2)/estrogen receptor α (ERα) signaling activates

Objective To construct a three-dimensional finite element model to investigate the biomechanical mechanism of carotid blast injuries.Methods Based on the head and neck CT angiography data of a healthy male volunteer,the 3D geometric model was extracted by Mimics software.The 3D solid model was obtained by fitting the geometric model to the non-uniform rational B-splines (NURBS) by Geomagic Studio software.The mesh of blood vessels,blood and soft tissue was divided by HyperMesh software to obtain the three-dimensional finite element model of the carotid artery.The material parameters and boundary conditions were set,and the vessel wall rupture damage threshold was 1 MPa.The dynamic process of carotid injury caused by MK3A2 grenade explosion shock wave at the distance of 60,70 and 80 cm to the neck was simulated using the LS-DYNA,generating the shock waveform and peak overpressure.The stress cloud map was used to analyze the stress distribution and damage morphology,and the stress curve was used to analyze the mechanical changes.Results The peak values of shock wave overpressure were 0.45,0.63 and 0.96 MPa at the distance of 80,70 and 60 cm away from the explosion center,respectively.At 80 cm,the peak stress of vessel wall was 0.43 MPa,and the vessel wall was not ruptured;at 70 cm,the peak stress of anonyma was greater than 1 MPa,which resulted in small rupture;at 60 cm,the peak stress of both anonyma the ascending aorta were greater than 1 MPa,leading to obvious rupture.The root part of the common carotid artery,anonyma and the arch of the aorta were high stress concentration areas,manifested as high-prevalence areas of damage and rupture.Conclusions The finite element model of explosive carotid artery injury is successfully constructed,which can be used to analyze the mechanical response and damage mechanism of carotid blast injuries.The main cause of injury and rupture is that the sudden change of stress in the process of explosion shock reaches or exceeds the threshold of vascular wall injury.Carotid artery rupture will occur when the vessel wall stress peak is greater than 1 MPa at 60 and 70 cm away from the explosion center,providing references for the clinical treatment and injury prevention.

The Chinese space station will be built around 2020. As a national space laboratory, it will offer unique opportunities for studying the physiological effects of weightlessness and the efficacy of the countermeasures against such effects. In this paper, we described the development of countermeasure systems in the Chinese space program. To emphasize the need of the Chinese space program to implement its own program for developing countermeasures, we reviewed the literature on the negative physiological effects of weightlessness, the challenges of completing missions, the development of countermeasure devices, the establishment of countermeasure programs, and the efficacy of the countermeasure techniques in American and Russian manned spaceflights. In addition, a brief overview was provided on the Chinese research and development on countermeasures to discuss the current status and goals of the development of countermeasures against physiological problems associated with weightlessness.
China ; Humans ; Program Evaluation ; Space Flight ; Weightlessness ; Weightlessness Simulation

Objective To investigate the value of computer aided design and 3D printing model in operation for complex mandibular fractures.Methods The clinical data of 136 patients with complex mandibular fractures treated from June 2006 to June 2016 were retrospectively analyzed.The patients were divided into 3D group (n =28) and conventional group (n =108) based on the use of computer aided design and 3D printing model.There were 24 males and four females in 3D group,with the age of (33.8 ± 15.4) years.There were 91 males and 17 females in conventional group,with the age of (30.3± 11.9)years.The 3D group used computer aided design and 3D printing model to develop the surgical plan,and the conventional group used traditional CT scan image data.The operation time,intraoperative blood loss,incidence of postoperative adverse events,and the distance differences between the ipsilateral and the five contralateral maxillofacial markers were compared between the two groups (△L1:the difference between the mandibular angle point and the condyle apex;△L2:the difference between the mandibular angle point and the chin vertex;△L3:the difference between the apex of the chin and the apical point;△L4:the difference between the inner mandibular angle point and the Inferior alveolar margin point;△L5:the distance between the inner mandibular angle and the sagittal plane).Results The operation time in the 3D group and the conventional group were 155 (126.25,183.75)min and 235 (156.25,268.75)min,respectively.The intraoperative blood loss in the 3D group and the conventional group were 100 (50.0,187.5) ml and 125 (100.0,200.0) ml,respectively.In the 3D group,one patient had mild occlusion disorder.In the conventional group,4 patients had postoperative infection,1 repulsion reaction of internal fixation device,and 19 mild occlusion disorder.The differences between the two groups in operation time and postoperative adverse events were statistically significant (P ＜ 0.05),but there was no significant difference in intraoperative blood loss (P ＞ 0.05).There was no significant difference between the ipsilateral △L and contralateral △L in two groups (P ＞ 0.05).No significant difference in △L4 was found (P ＞ 0.05),but there were significant differences in △L1,△L2,△L3,and △L5 between the two groups (P ＜0.05).Conclusion For patients with complex mandibular fractures,the use of computer-aided design and 3D printing model can helps shorten operation time,reduce postoperative adverse events and hence improve the fracture reduction outcome.

Objective:To establish the rat diabetic models by introperitoneal injection of streptozotocin (STZ) to observe the expressions of MMP-2 in retina tissue of the diabetic rats at different periods,and to clarify the effect of MMP-2 in the diabetic retiropathy (DR) of the diabetic rats.Methods:The femal SD rats were divded into normal control group (n=24),4-week model group (n=30),6-week model group (n=30) and 8-week model group (n=30).The rats in model groups were intraperitoneally injected with STZ for consecutive 5 d.The rats in normal control group were injected with sodium citrate solution at the same volume.The body weights and blood glucose levels of the rats in each group were measured at 4,6,and 8 weeks.The retina of each rat was removed;RT-PCR and Western blotting methods were used to detect the expression levels of MMP-2 mRNA and protein,and the immunohistochemistry was conducted to observe the morphology.Results:The body weights and blood glucose levels of the rats in each group had no differences (P＞0.05) before modeling.Three rats died in 4-week model group,5 rats died at 6 weeks and 7 rats died at 8 weeks.The body weights of the rats in model group were significantly lower than those in normal control group at the same time (P＜0.05 or P＜0.01),and the fasting blood glucose levels were signifieantly increased (P＜0.05 or P＜0.01).The expression levels of MMP-2 mRNA and protein in the retina tissue of the rats in model group were significantly higher than those in normal control group (P＜0.05).In normal control group,the retinal structure was clear and the cells were arranged in order,and the ganglion cells were arranged in a single layer;in model group,the retinal tissue structure was loose,the number of ganglion cells were significantly reduced,the inner nuclear layer and rod cell layer cell membrane outside were fuzzy.The MMP-2 positive cells were found to be brown yellow granules,especially in the cytoplasm of ganglion cells and vascular endothelial cells.The positive expression levels of MMP-2 in model group were higher than those in normal control group at 4,6,and 8 weeks.Conclusion:MMP-2 can express in the retina tissue of the diabetic rats.

Objective:To investigate the effects of BMP9 combined with NGF on the osteogenic differentiation of mesenchymal stem cells(MSCs).Methods:Recombinant BMP9 adenovirus was transfected into C3H10T1/2 cells.The cells were treated by GFP,NGF,BMP9 and BMP9 + NGF respectively.The expression level of COL1,RUNX2 was detected by RT-PCR and Western blot,ALP activity was examined by ALP kit 3,12,24,48 hours,3 and 7 days after treatment,respectively.Results:The ALP activity of BMP9 + NGF group was the highest among the 4 groups.The difference in the groups firstly appeared at 3 h after treatment.The highest expression level of RUNX2 and COL1 was detected in BMP9 + NGF group.Conclusion:NGF and BMP9 may synergisticly promote osteogenic differentiation at the early stage of osteogenic induction of C3H10T1/2 cells.