Objective To explore the abnormalities in the posterior cingulated cortex structure by voxel based morphometry(VBM)and changes of functional connectivity by resting-state functional magnetic resonance imaging(fMRI)in long-term heroin addictions.Methods High-resolution volumetric T1-weighted images and resting state fMRI examination were performed on 13 long-term heroin addicts and 14 matched healthy volunteers.The T1-weighted images were processed using optimized voxel-based morphometry to investigate abnormalities in the gray matter,at the sarne time,the posterior cingulated cortex was setted as the region-of-interest(ROI)seed,with which a whole-brain voxel temporal correlation in low frequency fMRI fluctuations was calculated,to find changes of the posterior cingulated cortex functional connectivity.Results Compared with the control group,gray matter concentration significantly decreased in the posterior cingnlated cortex,at the same time,the functional connectivity between the left posterior cingulated cortex and the right temporal lobe was increased,but the functional connectivity between the left posterior eingulated cortex and the left thalamus,the left parietal lobe,the left cerebrum were all decreased in heroin addicts.At the same time,the functional connectivity between the fight posterior cingulated cortex and the left thalamus,the left parietal lobe,the left frontal lobe were decreased in heroin addicts(t testing,P<0.01).Conclusion The structure and the functional connectivity in posterior cingulated cortex in long-term heroin addicts are changed,which may affect the dysfunction of the addictive brain and the function of reward mechanism.

Objective To observe the expressions of oxidized low density lipoprotein ( OxLDL ) receptor CD36 in kidney tissue of diabetic rats and in tubular cells incubated with OxLDL, and to explore the association of CD36 with the tubular injury and renal fibrosis in the process of diabetic nephropathy. Methods Diabetic rat model with hyperlipidemia was established by feeding with high sugar and fat diet and injection of low dose streptozotocin intraperitoneally. The expression of CD36 in kidney tissues was analyzed immunohistochemically. Meanwhile, the tubular sclerosis and fibrosis injury index were estimated and calculated. NRK-52E cells were stimulated with 50 mg/L OxLDL for 5, 10, 24, and 48 h, or 100 and 150 mg/L OxLDLs for 2 and 3 days. The protein expression of CD36 was detected by Western blot. Results The expression of CD36 in the renal tubulointerstitium of diabetic rats was increased comparing to that in control rats, and was localized mainly at tubular region. The renal tubular damage index(STI)ofdiabetesgroupwashigherthanthatincontrolgroup(5.54±1.5vs0.65±0.15,P<0.05). OxLDL stimulated CD36 expression in NRK-52E cells in a dose-and time-dependent manner. Conclusion The expression of CD36 was increased in renal tubular of diabetic rats, in consistent with STI. OxLDL increased CD36 expression in NRK-52E cells. These results suggest that the expression of CD36 is associated with renal tubular damages in experimental rat diabetes.

Objective:To investigate the orthodontic needs and to analyze the influencing factors of orthodontic treatment of university students in Xi'an.Methods:The orthodontic questionnaire survey was conducted in university students by stratified cluster random sampling,the Dental health component(DHC)and aesthetic component(AC)in the orthodontic treatment needs index were used as the objective indicators of orthodontic treatment needs,and the self-perceived aesthetic component(SAC)of the subjects was used as the subjective indicator of the need for orthodontic treatment.Univariate and multivariate logistic regression analysis were used to determine the influencing factors of university students'willingness to orthodontic treatment.Results:A total of 1135 university students were sur-veyed,including 578 males and 557 females.There were 224(19.74％),184(16.21％)and 120(10.57％)university students who required orthodontic treatment by DHC,AC and SAC analysis,respectively.Among the 224 university students who needed orthodontic treatment by DHC,68(30.36％)were willing to undergo orthodontic treatment,and 156(69.64％)were unwilling.Univariate and multivariate logistic regression analysis showed that gender,malocclusion,cognitive situation and social environment were independent influencing factors affecting the treatment intention.Conclusion:The objective orthodontic demand of Xi'an university students is high,but the demand for subjective orthodontic treatment is low.Gender,malocclusion,cognitive situation and social environment are the in-dependent influencing factors of university students'orthodontic treatment intention.

Objective To explore the Effects of nursing model on anxiety and sleep of laparoscope cholecystectomy ( LC) patients based on story theory. Methods Totally 50 cases of LC patients were divided into the observation group and the control group according to convenience sampling method, with 25 cases in each group. Patients in the control group received routine nursing care, while patients in the observation group received nursing intervention based on the the story theory. Self-rating Anxiety Scale ( SAS) and Pittsburgh Sleep Quality Index ( PSQI ) were used to evaluate patients′ anxiety and sleep status before and after the intervention. The plasma cortisol concentration of patients in two groups were compared before and after the intervention.Results The SAS score in the observation group after surgery was (33.76±4.62);the PSQI score was (8.28±1.54);the plasma cortisol concentration was (17.35±6.32) ng/mL, and they were all lower than the data in the control group. Repeated measurement anova showed that the differences of SAS score, PSQI score and plasma cortisol concentration in two groups at different time were significant ( Ftime=12.230,16.512,18.041;P<0.05) , and in a downward trend. The nursing effect in the observation group was superior than that in the control group.Conclusions The nursing model based on story theory could significantly improve the anxiety and sleep of LC patients, which was conducive to the rehabilitation of patients after surgery.

Polyhydroxyalkanoates (PHAs) have obtained much attention in biomaterial fields due to their similar physicochemical properties to those of the petroleum-derived plastics. Poly(3-hydroxybutyrate-co-lactate) [P(3HB-co-LA)] is one member of the PHAs family, and has better toughness and transparency compared to existing polylactic acid (PLA) and poly[(R)-3-hydroxybutyrate] [P(3HB)]. First, we confirmed the one-step biosynthesis of P(LA-co-3HB) with the lactate fraction of 23.8 mol% by introducing P(3HB-co-LA) production module into Escherichia coli MG1655. Then, the lactate fraction was increased to 37.2 mol% in the dld deficient strain WXJ01-03. The genes encoding the thioesterases, ydiI and yciA, were further knocked out, and the lactate fraction in the P(3HB-co-LA) was improved to 42.3 mol% and 41.1 mol% respectively. Strain WXJ03-03 with dld, ydiI and yciA deficient was used for the production of the LA-enriched polymer, and the lactate fraction was improved to 46.1 mol%. Notably, the lactate fraction in P(3HB-co-LA) from xylose was remarkably higher than from glucose, indicating xylose as a potent carbon source for P(3HB-co-LA) production. Therefore, the deficiency of thioesterase may be considered as an effective strategy to improve the lactate fraction in P(3HB-co-LA) in xylose fermentation.
Escherichia coli/genetics* ; Hydroxybutyrates ; Lactic Acid ; Polyesters ; Polyhydroxyalkanoates ; Xylose