BACKGROUND:In vitro and in vivo studies of cel response to a variety of mechanical loadings have demonstrated the stimulation of bone formation by loads. However, the effects of different mechanical strains on the same cel s have never been adequately studied by far.
OBJECTIVE:To investigate the effects of different mechanical strains on rat bone marrow mesenchymal stem cel s.
METHODS:Rat bone marrow mesenchymal stem cel s were isolated and cultured in vitro. Bone marrow mesenchymal stem cel s were subjected to different stimulations including dynamic stretch, static stretch and hybrid stretch through the use of custom-made mechanical stretch device. Cel ular proliferation, alkaline phosphatase activity and mRNA expression of Runx2 of bone marrow mesenchymal stem cel s were detected and the secretion of osteocalcin was evaluated under three different stretch modes respectively.
RESULTS AND CONCLUSION:Compared to the control group, cel proliferation increased by 18.67%, however, alkaline phosphatase activity, Runx2 expression and osteocalcin secretion were not changed obviously in the static stretchgroup. Compared to the control group, alkaline phosphatase activity, Runx2 expression and osteocalcin secretion increased by 60.33%, 49.67%and 48%respectively;however, cel proliferation was inhibited, in the dynamic stretch group. Compared to the control group, cel proliferation was slightly, but not significantly, increased in the hybrid stretch group, and the alkaline phosphatase activity, Runx2 expression and osteocalcin secretion increased although the increases were not as apparent as those in the dynamic stretch group. These findings suggest that static mechanical strain can significantly promote cel proliferation, the dynamic mechanical strain more greatly promotes osteogenic differentiation of bone marrow mesenchymal stem cel s, and the hybrid mechanical strain promotes the proliferation and osteogenic differentiation of bone marrow mesenchymal stem cel s.

In comparison with the clinical PET scanner,PET scanner for small animals puts forward a higher demand in spacial resolution and sensitivity. This article describes the development of the PET scanner for small animals and compares the characteristics of several kinds of contemporary typical PET scanners for small animals in different aspects based on the development of detectors. Meanwhile,it also introduces the development of the detectors designed for measuring depth of interaction (DTC) to reduce parallax error.

Objective To investigate aberrant methylation in the promoter area of p16 gene and p16 protein expression in human pancreatic carcinoma and in the corresponding tumor-adjacent tissues,and evaluate their role in the carcinogenesis and progression of tumor and its clinical significance.Methods Immunohistochemistry and MSP(methylation-specific PCR)were performed on 46 samples of pancreatic carcinoma and their corresponding tumor-adjacent tissue specimens for p16 and its methylation.Results Expression rate of p16 protein was 41.3%(19/46)in pancreatic carcinomas,95.7%(44/46)in corresponding tumor-adiucent tissues.Through MSP,the methylation rate in pancreatic carcinomas was 39.1%.No gene methylation was found in 19 cases expressing p16 protein.p16 gene methylation was closely related to p16 protein expression in pancreatic carcinoma(P0.05);but were significantly related to the PTNM staging,histological differentiation,distant metastasis and lymph node metastasis(P

Objective To study the condition and method of hydrodynamics-based transgene(HDT) in rat fatty liver. Methods Inject different dosages and concentrations of green fluorescent protein plasmid pEGFP-C1 at different speeds, then collect 4 rats' liver leaves at different time points after injection and prepare their frozen section, finally observe and quantify the GFP expression with fluo rescence microscope at 488 nm excitation wavelength. Results Plasmid pEGFP-C1 concentration 33mg/L, injection speed 2ml/s, injection volume 8.5%of rat body weight, injected plasmid. After 6 hours of injection, GFP-positive cells rate of pedicel leaf is about 18%, left leaf about 14%, middle leaf about 12.5%;R3ight leaf about 10% and tail leaf about 8%. GFP begin to gradually reduce since 24 hours, until 72 hours almost no GFP-positive cells were checked in all liver leaves. Conclusion Hydrodynamics-based transgene can be applied to rat fatty liver, the appropriate conditions of this method are 33mg/L plasmid concentration, 8.5% rat avoirdupois, 2ml/s injection speed, and the suitable time to observe the proportion of GFP-positive cells is 6-24 hours after gene injection.

ObjectiveTo observe the therapeutic effects of Shenxiong glucose injection in the patients with chronic kidney diseases.Methods Seventy-eight patients with chronic kidney disease were given intravenous glucose injection 200 ml,qd,for 2 weeks.The patients who were complicated with diabetes would be given insulin 2 U/100 ml.Before and after Shenxiong injection treatment,24 h urinary protein,blood urea nitrogen ( BUN),creatinine ( Cr),hemoglobin ( Hb),albumin ( ALB),hematocrit ( HCT),fiber fibrinogen (FIB),cholesterol (TC) and triglyceride (TG) were measured and compared.Results After 1 course of Shenxiong treatment,the serum BUN,Cr,FIB,24 h urinary protein,Hb and HCT ( [ 15.70 ± 3.62 ] mmol/L vs.[6.74 ± 1.56 ] mmol/L,[ 564 ± 65 ] μmol/Lvs.[ 189 ± 43 ] μmol/L,[ 0.08 ± 0.01 ] g/L vs.[ 0.04 ± 0.01 ] g/L,[7.96 ±3.45]g vs.[3.60 ± 1.92]g,[83.6 ±10.5]g/L vs.[79.5 ±8.7]g/L,[0.43 ±0.0] vs.[0.39 ±0.06 ] were decreased,and ALB ( 28.7 ± 8.6) vs.( 36.8 ± 6.2) was increased.The difference was statistically significant (t =3.1 1,2.98,3.04,2.82,2.02,2.23,P＜0.01 for all).TC and TG were not changed much after the treatment.ConclusionShenxiong injection can improve the kidney function,lower Fibrinogen and urine protein,which may effectively slow down the progress of chronic kidney disease and improve the life quality.

Objective To study the conditions and methods of hydrodynamics-based transgene into rat regenerating liver in vivo. Methods The solution with concentration 30mg/L gene-containing plasmid was injected into rat tail veins at a speed of 2ml/s, then partial hepatectomy (PH) was performed at different times before/after injection, finally the rat (g) and regenerating liver (g) were weighed, and the liver coefficient (Lc) was calculated. Out of 15 groups which are Lc±Lc*0%, *5%, *10%, *15%, *20%, *25%, *30%, *35%, the most suitable group was chosen as correction coefficient to calculate the most appropriate volume of plasmid solution which was injected into the regenerating liver at different recovery times, and at the same time, right lobe of liver was gathered to make frozen section, then observe and quantify the positive green fluorescent protein (GFP) rate at 488 nm excitation wavelength. Results Injection of either physiological saline or empty plasmid has no significant difference compared with control (only PH performance). The appropriate time of hydrodynamics-based transgene is more than 12 hours before PH or anytime after PH. The solution volume of hydrodynamics-based transgene into liver regenerating rat after PH is rat weight (g) ×9%×1/3×corresponding correction coefficient (Trc). Both vector and target gene have effect on the time and abundance of gene expression. Conclusion Hydrodynamics-based transgene can effectively be applied to gene transfection in rat regenerating liver.

As a kind of physiological signals, the electroencephalogram (EEG) represents the electrical activity of the brain. Because of its higher time-varying sensitivity, EEG is susceptible to many artifacts, such as eye-movements, blinks, cardiac signals, muscle noise. These noises in recording EEG pose a major embarrassment for EEG interpretation and disposal. A number of methods have been proposed to overcome this problem, ranging from the rejection of various artifacts to the effect estimate of removing artifacts. This paper reviews many kinds of methods for artifact rejection in the EEC recently, including regression-based methods, artifact subtraction, principal component analysis (PCA), independent component analysis (ICA) and wavelet transform. The specific assumptions of each method and its advantage/disadvantage are also summarized.
Artifacts ; Brain ; physiology ; Electroencephalography ; methods ; Humans ; Principal Component Analysis ; Signal Processing, Computer-Assisted

The morbidity and mortality of stroke caused by large vessel occlusion are high,and its outcome is closely associated with emergency treatment.In order to receive treatment within the time window,the effective prehospital assessment is very important.The prehospital stroke scale simplifies emergency screening and assessment of such patients.Although the predictive value is good,its role remains controversial.This article reviews some of the prehospital stroke scales used to identify large vessel occlusions and analyzed the characteristics of different scales.

[Objective]To investigate the effects of traditional Chinese medicine acupuncture combined with 0.01%atropine eye drops on macular vascular density and retinal thickness in children with low myopia.[Methods]A total of 84 children(156 eyes)newly diagnosed as low myopia were randomly divided into an experimental group and a control group.The experimental group received traditional Chinese medicine acupuncture combined with 0.01%atropine eye drops,while the control group was treated with 0.01%atropine eye drops alone.Ophthalmic examinations were performed before and after six months of treatment,including uncorrected distance visual acuity(UCVA),axial length(AL),spherical equivalent(SE),and slit-lamp examination.Optical coherence tomography(OCT)was used in routine mode to measure macular ganglion cell-inner plexiform layer(mGCIPL)thickness,and optical coherence tomography angiography(OCTA)was employed to measure macular vascular density and the area of the foveal avascular zone(FAZ).Changes in various indicators before and after treatment were compared between the two groups.[Results]After six months of treatment,both groups showed significant increases in AL and SE compared with that before treatment(P<0.01).The differences in AL and SE were significantly smaller in the experimental group than in the control group(P<0.05).No significant changes in intraocular pressure(IOP)were observed in either group before and after treatment(P>0.05).Compared to before treatment,both groups exhibited significant increases in mGCIPL thickness(P<0.01,P<0.05).Central circle macular vessel density(cCVD)increased in the experimental group(P<0.01),while there was no significant changes in outer circle macular vessel density(oCVD),inner circle macular vessel density(iCVD),whole circle macular vessel density(wCVD)or FAZ(P>0.05).After six months of treatment,no correlation was found between cCVD and AL or SE in the experimental group(P>0.05),but cCVD was positively correlated with mGCIPL thickness(r=0.448,P<0.05).[Conclusion]Traditional Chinese medicine acupuncture combined with 0.01%atropine eye drops can further reduce the growth rate of AL and diopter in children with low myopia.Additionally,this combined treatment increases cCVD and mGCIPL thickness in these children.

Objective To briefly retrospect the production and quality control of 64 Cu(n = 9) in Department of Nuclear Medicine of Peking University Cancer Hospital in order to provide useful information for the further production and application of this novel radionuclide. Methods 64 Ni(p, n) 64 Cu nuclide re-action was used for the 64 Cu production. Firstly, a new electro-planting device for 64 Ni planting was de-signed. HM-20 cyclotron was applied to irradiate the slice for 5-8 h. 64 CuCl2 was purified, collected and in-jected into normal mice. MicroPET was conducted to monitor the metabolism in vivo. Results A new type of electro-planting device was designed and assembled. The enriched 64 Ni target showed smooth, even, dense surface and without obvious pits and cracks. High specific 64 Cu (1.3-4.1 GBq) can be collected after radio-chemical purification. 64 Cu was finally dissolved in 0.01 mol/ L HCl with high radionuclide purity (over 99.97％). MicroPET of 64 CuCl2 in normal mice showed that the radioactivity was mainly accumulated in the liver. Conclusion A new and real-time observable device for 64 Ni electro-plating has been designed and successfully used in the production of 64 Cu with high specific activity.