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 rat diabetes and eye disease models by injection of STZ and explore the therapeutic effect of panaxnotoginseng polysaccharides (PNP) on the diabetes and eye diseases of the model rats,and to clarify their mechanisms.Methods:Seventy SD male rats were randomly divided into blank control (n=10) and model groups (n=60), and the rats in model group were fed with high fat diet. 2 weeks later, the rats in model group were intraperitoneally injected with 35 mg·kg-1 STZ to establish the models.And 3 d later, the rats were treated with fasting and water deprivation for 12 h,the fasting blood glucose (FBG)was tested, and the models were assessed to be successful as the FBG>11.1 mmol·L-1.The rats with hyperglycemia were selected and divided into model, melbine(150 mg·kg-1), and low, middle and high doses (75,150 and 300 mg·kg-1) of PNP groups.After orally administration for 5 and 8 weeks, the FBG levels of rats were recorded.And 8 weeks later, the sugar tolerance, hepatic glycogen levels,serum glutathione(GSH) and nitric oxide(NO) levels of the rats were tested.The rat retinas were removed to analyze the expression levels of vascular endothelial growth factor(VEGF) and inducible nitric oxide synthase(iNOS) by using Q-PCR.The pathological changes of retinas were observed by HE staining method.Results:Compared with model group,the FBG level in middle dose of PNP group was decreased 5 weeks after treatment(P<0.05).Eight weeks later, compared with model group, the levels of FBG, sugar tolerance and hepatic glycogen in different doses of PNP groups were all decreased (P<0.05 or P<0.01).Compared with model group, the level of serum GSH in high dose of PNP group was remarkably increased(P<0.01), and the NO level was significantly decreased (P<0.05 or P<0.01).Compared with model group, the expression levels of VEGF and iNOS in high dose of PNP group were significantly decreased (P<0.05).The results of HE staining showed that the neurodeatrophia of the rats in low and middle doses of PNP groups were improved;and the vascular proliferation and neurodeatrophia of the rats in high dose of PNP group were significantly improved.Conclusion:PNP could decrease the blood sugar, increase the levels of GSH and NO, and up-regulate the gene expression levels of VEGF and iNOS, resulting the treatment of diabetes and its related retinopathy.

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.

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.

OBJECTIVEPrevious studies have clarified that calcitonin gene-related peptide (CGRP) can promote the biologi- cal activity of osteoblasts. To further reveal the role of CGRP in bone repair, we studied its influence on osteogenic differentia- tion of mouse bone marrow stromal cells (BMSCs) and initially explored the effect of the Hippo signaling pathway with this process.

METHODSBMSCs were induced to osteogenic differentiate osteoblasts by different concentrations of CGRP for a screening of the optimal concentration. CGRP was added in BMSCs, then the activity of alkaline phosphatase (ALP) and the number of mineralized nodules were examined by specific ALP kits after 48 hours and alizarin red staining fluid after 7 days, respectively. The protein expression of p-Mst1/2 was measured by Western blot. Verteporfin was used to block the downstream Yap signaling. The mRNA expression of collagen type I (Col I) and runt-related transcription factor 2 (Runx2) were detected by reverse transcription-polymerase chain reaction.

RESULTSCompared to the blank group, different concentrations of CGRP (10⁻⁹, 10⁻⁸, 10⁻⁷ mol · L⁻¹), especially 10⁻⁸ mol · L⁻¹, significantly increased the ALP activity of BMSCs (P < 0.05). Alizarin red staining also showed more mineralized nodules in 10⁻⁸ mol · L⁻¹ group. The expression of p-Mst1/2 increased in the CGRP group (P < 0.05). Verteporfin treatment effectively decreased the mRNA expression of Runx2 and Col I (P < 0.05).

CONCLUSIONThe Hippo signaling pathway plays a role in CGRP-induced osteogenic differentiation in mouse BMSCs.

Alkaline Phosphatase ; Animals ; Calcitonin ; genetics ; metabolism ; Calcitonin Gene-Related Peptide ; metabolism ; Cell Differentiation ; Cells, Cultured ; Collagen Type I ; Core Binding Factor Alpha 1 Subunit ; Mesenchymal Stromal Cells ; physiology ; Mice ; Osteoblasts ; Osteogenesis ; physiology ; Signal Transduction