BACKGROUND:Many studies reported the relationship of the mechanical properties and water content about bone tissue, which is one of organizations containing the lowest water content on human body. Researches on effect of water on biological tribology behavior of bone tissue have been rarely reported and are the experimental study generally. OBJECTIVE:To explore the influence and the damage mechanism of water on biological tribology behavior of bone tissue, by comparing multiscale numerical model established with the experiment. METHODS:Dehydration of the bone tissue was studied by nanoindentation test and both reciprocating sliding and impact wear tests. A multi-scale finite element model was constructed under a flat-on-ball configuration. RESULTS AND CONCLUSION:The viscoelasticity and the tribological properties of bone tissue significantly decreased as well as the different wear mechanisms under applied loading after drying. The analytical results indicated that there were high stress condition, which incurred the micro-crack initiation and the appearance of peeling and wear, around the Haversian canal, circumferential lamellas and the interstitial tissues. Meso-scale:dehydration weakened the function of absorption and interruption of stress, which facilitated crack extension in pore. Micro-scale:the high stress gradient of structure of canaliculi and lacunae is an important cause of tissue damage.

Objective To evaluate the left ventricle geometry shape and left heart regional function in mitral insufficiency (MI) by quantitative tissue velocity imaging (QTVI) and the left ventricle systolic and diastolic geometry spbericity index. Methods Thirty normal subjects and 62 MI patients underwent QTVI and color Doppler imaging (CDFI) were enrolled in this study in order to measure the left ven-tricular geometry shape and left ventrieular regional function along LV apical long-axis view. Off-line LV regional velocity images along LV apical long-axis view were synchronously obtained. Peak tissue velocities of LV regional muscular tissue during systole(Vs),systolic acceler-ation(a), early diastole(Ve), LA contraction(Va)were synchronously measured as the index of left ventricular regional systolic and dias-tolic function. The left ventricle geometry shape index were reflected from the systolic and diastolic geometry sphericity index (SIs and Sid) and the left ventrieular ejection fraction (LVEF) and the peak D and peak a (PVd/PVa) of pulmonary veins flowing spectrum reflected the global left ventricular function index. The Vs, Ve, Va, a, PVd/PVd ratio, LVEF, SIs, SId were recorded and their correlation between normal subjects and patients with MI were compared. Result Vs, Ve,Va,a,PVd/ PVa ratio,SIs,SId in patients with MI were significantly re-duced. There was positive relation between Sis and a(r=0.602)and Ve/Va and SId(r=0.635). Conclusion There was negative rela-tion between regional cardiac function and LV spberieity, the higher cardiac function was accompanied with the lower SI.

Objective:To investigate the protective effects and possible mechanisms of cortex phellodendri water extract and etha -nol extract on the myocardial injury induced by pituitrin and isoproterenol hydrochloride in rats .Methods:SD rats as the experimental animals were randomly divided into the normal control group , model group , compound Danshen tablets group , phellodendron water ex-tract group and phellodendron ethanol extract group .Pituitrin and isopropyl adrenaline hydrochloride were used to establish the myocar-dial injury model in rats.The serum CK, LDH activity, myocardial tissue SOD activity and MDA content were detected and compared . Results:Compared with those in the normal control group , the serum LDH activity , CK activity and MDA content were significantly in-creased , and the SOD activity in cardiac muscle and myocardial tissue was significantly decreased in the pituitrin -established myocardi-al injury model group (P<0.01).In the isopropyl adrenaline hydrochloride-established myocardial injury model group , the MDA con-tent in myocardial tissue was obviously increased , and the SOD activity in myocardial tissue was decreased obviously (P<0.01).The serum LDH activity, CK activity and MDA content were significantly decreased , and the SOD activity in cardiac muscle and myocardial tissue was increased significantly in all drug-taken groups when compared with those in the pituitrin-established myocardial injury model group, and the differences were statistically significant (P<0.05 or P<0.01).The MDA content in myocardial tissue was significant-ly reduced , and the SOD activity was increased significantly in all drug-taken groups when compared with those in the isopropyl adrena-line hydrochloride-established myocardial injury model group , and the differences were statistically significant (P<0.05 or P<0.01). Conclusion:Cortex phellodendri extract has certain protective effect on myocardial injury induced by pituitrin and isopropyl adrenaline hydrochloride in rats .

Objective To assess the irregular shape of hematoma with math methods,which is one of the risk factors of hematoma enlargement.Methods We reviewed images data of patients with spontaneous intracerebral hemorrhage treated nonsurgically who underwent initial computed tomography (CT) within 6 hours and repeated CT within 48 hours of onset.The area(s),the circumference(L),the greatest diameter(A)and the transverse diameter(B)of the greatest hemorrhage CT slice was measured.The formula X=L/S waft used to calculate the value.We calculated the area(S1)and the circumference (L1) of the ellipse with A as its long diameter and B as its short diameter.The formula X1=S1/L1 was used to calculate the value. We used formula R=X/X1 to assess the irregular hematoma shape.The relationships between hematoma enlargement and R was analyzed. Results Thirty-one patients(25.8%) showed enlarged hematomas after admission.The larger the value of R,the more irregular the shape of hematoma.When R≥1.3,the shape of the hematoma was significantly irregular.36.0% patients with R≥1.3 had hematoma enlarged.compared with only 18.6% those with R<1.3(χ2=4.62,P=0.032).Conclusions The irregular shape index R Can be used to assess the shape of a hematoma. A particularly high likelihood of hematoma enlargement is observed in patients with an irregularly shape index R≥1.3.

Objective To discuss features of angiogenesis in degenerative intervertebral disc and related factors.Methods In this case-control study,52 patients undergoing single level posterior lumbar interbody fusion during October 2012 to December 2013 were selected as research objects.Annulus fibrosus,nucleus pulposus and cartilage end plate of responsible level were collected in surgery for frozen section and HE staining.Angiogenesis in the intervertebral disc was identified according to the morphological characteristics of vascular endothelial cells,i.e.typical lumen structure and blue stained nucleus.These intervertebral disc specimens were divided into two groups according to the angiogenesis phenomenon.All specimens with angiogenesis were evaluated by blood micro-vessel density (MVD) counting.Related factors of angiogenesis including gender,age,VAS score,JOA lumbar score,classification of lumbar intervertebral disc degeneration,intervertebral disc calcification rate and classification of intervertebral disc herniation were compared between the two groups.Logistic regression analysis was further conducted on indicators with differences of statistical significance.Results In our group of 52 patients,28 patients had obvious angiogenesis:12 patients in annulus fibrosus,7 patients in cartilage endplate and 9 patients in annulus fibrosus and nucleus pulposus.Angiogenesis rate was 53.8％ (28/52).The mean value of MVD was 12.5±3.1.24 patients did not have obvious angiogenesis.Intervertebral disc calcification rate (75.0％ vs.37.5％),VAS score (6.79±2.06 vs.5.25±2.23) and JOA lumbar score (16.32±3.89 vs.19.08±4.24) were significant differences between two groups (P=0.006,0.013,0.018).Multi-factor regression analysis showed that VAS score (OR=7.248,P=0.011) and intervertebral disc calcification (OR=8.881,P=0.006) were important factors associated with intervertebral disc angiogenesis.JOA lumbar score (OR=3.739,P=0.070) was not associated with intervertebral disc angiogenesis.Conclusion Degeneration of the intervertebral disc is accompanied by angiogenesis.Intervertebral disc calcification and VAS score are important factors associated with angiogenesis in intervertebral disc.

[Objective] To investigate the effect of mitogen-activated protein kinases (MAPK) on cerebral ischemia induced by photothrombosis in Swedish amyloid precursor protein (APP/SWE) transgenic mice.[Methods] In APP/SWE transgenic mice and non-transgenic mice (n ＝ 12,respectively),photothrombotic stroke was induced,on 7 d after cerebral ischemia,the amount of the survival neuron in the penumbra was counted using Nissl staining (n ＝ 6),and the activities of p38MAPK and JNK were measured by Western blot (n ＝ 6).[Results] On 7 d after cerebral ischemia,ratio of amount of survival neuron over the penumbra in hippocampus in the ischemic side to that in the non-ischemic side in the non-transgenic mice group (78.3 ± 1.3)% was significantly higher than that in the APP/SWE transgenic mice group (70.5 ± 1.4)% (P ＜ 0.05);compared with the non-ischemic hemisphere,the activities of p38 MAPK and JNK increased significantly in the ischemic hemisphere in the APP/SWE transgenic mice group (P ＜ 0.05),whereas,there was no significant difference between ischemic and non-ischemic hemisphere in the non-transgenic mice group (P ＞ 0.05).[Conclusion] Photothrombosis causes more severe damage in the APP/SWE transgenic mice group than that in the non-transgenic mice group.The possible mechanism includes the increased activities of MAPK which enhance the process of neuronal cell apoptosis.

A novel unsaturated polyphosphoester (UPPE) was devised in our previous research, which is a kind of promising scaffold for improving bone regeneration. However, the polymerization process of UPPE scaffolds was unfavorable, which may adversely affect the bioactivity of osteoinductive molecules added if necessary, such as recombinant human bone morphogenetic protein-2 (rhBMP2). The purpose of this study was to build a kind of optimal scaffold named UPPE-PLGA-rhBMP2 (UPB) and to investigate the bioactivity of rhBMP2 in this scaffold. Furthermore, the cytotoxicity and biocompatibility of UPB scaffold was assessed in vitro. A W1/O/W2 method was used to fabricate PLGA-rhBMP2 microspheres, and then the microspheres were added to UPPE for synthesizing UPB scaffold. The morphological characters of PLGA-rhBMP2 microspheres and UPB scaffolds were observed under the scanning electron microscopy and laser scanning confocal microscopy. The cumulative release of UPB scaffolds was detected by using ELISA. The cytotoxicity and biocompatibility of UPB scaffolds were evaluated through examining the adsorption and apoptosis of bone marrow stromal cells (bMSCs) seeded on the surface of UPB scaffolds. The bioactivity of rhBMP2 in UPB scaffolds was assessed through measuring the alkaline phosphates (ALP) activity in bMSCs seeded. The results showed that UPB scaffolds sequentially exhibited burst and sustained release of rhBMP2. The cytotoxicity was greatly reduced when the scaffolds were immersed in buffer solution for 2 h. bMSCs attached and grew on the surface of soaked UPB scaffolds, exerting well biocompatibility. The ALP activity of bMSCs seeded was significantly enhanced, indicating that the bioactivity of rhBMP2 remained and still took effect after the unfavorable polymerization process of scaffolds. It was concluded that UPB scaffolds have low cytotoxicity, good biocompatibility and preserve bioactivity of rhBMP2. UPB scaffolds are promising in improving bone regeneration.

Objective To explore the causes of per-hospitalization high inpatient expenditure of a tertiary hospital in 2015,by analyzing the influencing factors.Methods We retrospectively studied 1 282 inpatient cases who cost more than 100 000 yuan per case at a tertiary hospital in 2015,analyzing statistically major influencing factors of such expenditure in variance analysis and multiple stepwise regression analysis.Results The average days of stay of these cases were 27.6 days,and the average medical cost of those cases was 149 153 yuan per person.Costs for medicines and material made up a large proportion of medical costs,respectively accounting for 33.38% and 31.98% of the total.The days of stay,prognosis of the patient,complications as well as hospital infection,surgeries,gender of the patients constituted major factors on inpatient medical expenditure.Conclusions Reducing the average days of stay,guiding reasonable applications of drugs and medical materials,strengthening management on operations and controlling excessive medical services are effective approaches to reducing excessive growth of medical costs.

Objective To study the anti-tumor effects of alcohol extraction of Coix stalk objects on H22 tumor-bearing mice. Methods The animal model of tumor bearing mice with H22 ascitic tumor cells was established. Eighty-four model mice were randomly and equally divided into Coix stalk extract groups 1-5 (10, 8, 6, 4 and 2 g/kg), model control group and cyclophosphamide group. Mice were treated orally with Coix stalk alcohol extraction solution (10, 8, 6, 4 and 2 g/kg), cyclophosphamide 0.02 g/kg and normal saline once a day for 8 days for Coix stalk extract group, cyclophosphamide group and model control group. The mouse activity, the size and the appearance of time of abdominal swelling, and changes of hair, feeding and drinking water quantity were observed in groups of mice. The solid tumor mass was measured in H22 tumor-bearing mice. The tumor inhibitory rate, liver index, spleen index and thymus index were calculated. Results The axillary tumor muster was found first in model control group with the fastest growth, reduced independent activity, decreased appetite and dim in hair color, followed by the Coix stalk extract group 1 and group 2. The last was Coix stalk extract group 5 and cyclophosphamide group. The solid tumor mass were (0.47±0.18), (0.37± 0.13), (0.34±0.10), (0.30±0.11) and (0.28±0.09) mg for Coix stalk alcohol extract groups 1-5, which were significantly lower than those of model control group (0.60 mg±0.21 mg, F=5.700,P<0.05). The tumor inhibition rates were 21.67%, 38.33%, 43.33%, 50.00%, 53.33%and 60.00%in Coix stalk extract groups 1-5 and cyclophosphamide group. The liver index, spleen index and thymus index were lower in cyclophosphamide group and Coix stalk alcohol extract groups than those of model control group (except for the spleen index of Coix stalk extract group 1). The liver index was lower in Coix stalk ethanol extract groups than that of cyclophosphamide group. There were no significant differences in the spleen index, thymus index between Coix stalk ethanol extract groups and cyclophosphamide group. Conclusion Coix stalk alcohol extract has inhibitory effects on the tumor and liver damage in H22 mice.

ObjectiveTo investigate the feasibility of Legacy pedicle screw system plus minimally invasive technique in treatment of Tile type C pelvic fracture and evaluate its therapeutic effects.MethodsFrom January 2008 to March 2010, 12 patients with closed Tile type C pelvic fractures were treated with Legacy pedicle screw system plus minimally invasive technique.There were seven males and five females, at age range of 21-60 years (average 39.6 years).All patients had sacrum fractures of the posterior pelvic rings.The anterior pelvic ring fractures included unilateral ischiadic ramus fractures in four patients and bilateral ischiadic ramus fractures in eight.Three patients were combined with shock.The anterior pelvic rings were fixed with minimally invasive reconstruction plates and the posterior pelvic rings fixed with minimally invasive technique plus Legacy pedicle screw system.ResultsThe operation lasted for average 90 minutes (range, 80-110 minutes) , with average intraoperative blood loss of 105 ml (range, 80-150 ml).All patients were followed up for average 18 months (range, 6-32 months), which showed that all patients got satisfactory reductions and that the fractures were healed at one stage, with average period of 11.5 weeks (range, 9-13 weeks).There occurred no infections, failures of internal fixations or nerve injuries.According to improved Lindahl standard of pelvic injury function assessment, the result was excellent in 10 patients and good in two, with average score of 78.6 points.Conclusions Under master of the surgical indications, Legacy pedicle screw system plus minimally invasive technique takes advantages of minor trauma, less intraoperative fluoroscopy, short operation time, good curative resuhs and few complications in treatment of Tile type C pelvic fractures by fixation of the posterior pelvic rings and reconstruction of the anterior pelvic rings.