BACKGROUND:At present,syndromes happening frequency of diabetes mellitus can be controlled through regulating glucose concentration in blood.Therefore,a fast,steady,accurate glucose biosensor has been an intense area of focus for investigators.OBJECTIVE:To observe the effect of chitosan-gold nanoparticles hybrid film on electrochemical glucose biosensor.DESIGN,TIME AND SETTING:The observation experiment was performed at the Department of Medicine Laboratory,General Hospital,Guangzhou Military Command of Chinese PLA from February to April 2009.MATERIALS:Based on the immobilization of glucose oxidase (GOD) with cross-linking in the matrix of chitosan on an Au electrode by glutaraldehyde,a novel glucose biosensor was constructed with gold nanoparticles by electrodeposition.METHODS:The properties of CHIT/AuNPs hybrid film modified electrode were characterized by cyclic voltammetry (CV) in 20 mmol/L K3Fe (CN)6-0.1 mol/L KCI system by using the three-electrode system and the response to glucose was investigated by linear scan voltammetry (LSV).The optimal experiment conditions,stability and reproducibility about the glucose biosensor were also studied.MAIN OUTCOME MEASURES:The cyclic voltammetry properties of different modified electrode,as well as relation between glucose concentration and response current.RESULTS:Glucose concentration showed a linear correlation with response current in range of 0.001-6 mmol/L.The biosensor exhibited excellent performances of producibility,stability and the ignorance interferences of reducing substances,with the CONCLUSION:The glucose biosensor possesses excellent reproducibility and stability with a fast response time to glucose,which can be used in detection of glucose concentration in human serum.

OBJECTIVE:To compare the effects of total knee arthroplasty performed with and without patellar resurfacing. METHODS:All randomized clinical trials relevant to comparison of total knee arthroplasty performed with and without patellar resurfacing between 1966 and 2008 were collected. The quality of the trials was assessed. The outcomes data including the prevalence of reoperations,postoperative anterior knee pain,patient satisfaction,and the improvement in various knee scores were extracted and reviewed systematically. RESULTS:1 731 knees were included in the 15 published trials,including 842 knees in the resurfaced group and 889 in the nonresurfaced group. During the four years following surgery,there was no significant difference between the resurfaced and the nonresurfaced groups in re-operation rate (relative risk=0.56,95% CI 0.17-1.85); whereas the re-operation rate of the nonresurfaced group was significantly greater than resurfaced group 4 years after surgery (relative risk=0.46,95% CI 0.25-0.84). On the prevalence of postoperative anterior knee pain,there was no significant difference between two groups (relative risk=0.65,95% CI 0.35-1.21). No significant difference was found in patient satisfaction (relative risk=1.00,95% CI 0.95-1.05). There was no significant difference between the resurfaced and the nonresurfaced groups in the KSS scores (weighing mean difference:-0.41; 95% CI:-3.08 to 2.26). CONCLUSION:The long-term rate of reoperations in total knee arthroplasty performed with patellar resurfacing was lower than that without patellar resurfacing. There were no significant differences in the terms of prevalence of postoperative anterior knee pain,patient satisfaction,and the improvement in various knee scores between the resurfaced and the nonresurfaced groups. The results of this systematic review should be explained prudently because of some limitations of included trials. For more reliable conclusions,more trials with high quality on methodology are needed.

Objective To construct a kind of novel electrochemical glucose biosensor for clinical detection.Methods Multiwall carbon tube(MWCNTs),NanoAu and glucose oxidase(GOD) were immobilized on the Au electrode by monolayer self-assemble.Cyclic voltammetry and linear scan voltammetry were used to investigate the assembling process and the chemical characteristics of the glucose biosensor.Results The linearity of glucose in the range of 10～1 400 mg/L with the correlation coefficient of R2=0.990 9 was obtained by linear scan voltammetry and the detection limited reached 0.000 1 mg/L.The four criterion samples were measured with 3 different biosensors in same conditions and the RSD

BACKGROUND:In order to promote the recovery of nerve function after peripheral nerve injury, we should try to accelerate the regeneration of injured nerve axons on one hand, and try to improve the accuracy of proximal and distal nerve docking on the other hand. OBJECTIVE:To explore the selective regeneration of nerve axons after peripheral nerve injury in models with crush injury and freeze injury. METHODS:Total y 110 healthy male Sprauge-Dawley rats, 8 weeks old, were selected and randomly divided into three groups. The rates received crush injury, freeze injury and normal control ed surgery on femoral nerve trunk. At 2, 3, 6 and 12 weeks after modeling, general behavioral examination was performed, and then pure blue and red fluorescence were used to label the wrong-way ingrowth saphenous nerve and correct ingrowth femoral nerve muscular branches respectively;retrograde labeling the motor neurons in order to observe the distribution and amount of tracer in spinal cord anterior horn;electrophysiological examination was performed at 8 weeks after modeling, and analyzed statistical y. RESULTS AND CONCLUSION:Rats from both crush injury group and freeze injury group displayed decreased motion radius of hind limbs after surgery, and the stretch function was limited;but with time prolonging, the functions were recovered. The motor evoked potentials could be observed at the quadriceps, and there was no significant difference between two groups (P>0.05). The number of neurons stained red in the spinal cord anterior horn was increased gradual y in both crush injury group and the freeze injury group under fluorescence microscope. The number of neurons stained red in the crush injury group was significantly higher than that in the freeze injury group (P<0.05), and the number of blue-stained and purple-stained neurons was decreased gradual y. The results suggest that keeping the perineurium intact can gain accurate docking in axon regeneration and the recovery of injured limb functions, even though the damaged range is large.

BACKGROUND:There is a high prevalence of spinal tuberculosis in developing countries. Beside systematic chemotherapy, there are stil some patients who need surgical treatment at certain phase of systematic treatment. However, there is no standard method for surgical treatment of spinal tuberculosis yet. OBJECTIVE:To systematical y evaluate the effect of anterior approach and posterior approach through consulting the literatures on the comparison between anterior approach and posterior approach for the treatment of spinal tuberculosis. METHODS:The PubMed database, Medline database, Elseveir database, Wanfang database and CNKI database were searched with the key words of“thoracolumbar tuberculosis, control ed randomized trial, RCT, anterior, posterior”in Chinese and English. The randomized control ed trials on the comparison between anterior approach and posterior approach for the treatment of spinal tuberculosis were included. The operative time, intraoperative blood loss, correction degree of Cobb angle, loss of Cobb angle at final fol ow-up, al ograft fusion time, total hospital stay and the excellent and good rate of the effectiveness were compared by Revman5.1 software. RESULTS AND CONCLUSION:A total of 1 438 articles were screened out, and final y 9 randomized control ed trials were included. The total number of patients was 692, in which 324 were treated with anterior approach and 368 were treated with posterior approach. The operative time of anterior approach of 46.25(40.23, 52.26) minutes was less than that of posterior approach;the intraoperative blood loss of anterior approach of 148.91(135.12, 1 625.70) mL less than that of posterior approach;the correct degree of Cobb angle of anterior approach of 2.40°(2.21°, 4.62°) was smal er than that of posterior approach;the loss of Cobb angle of anterior approach of 0.66°(0.41°, 0.91°) was larger than that of posterior approach;the total hospital stay of anterior approach of 0.34 (-0.32,1.01) days was less than that of posterior approach;the al ograft fusion time of anterior approach was less than that of posterior approach for 0.26 (0.18, 0.34) months;the number of cases with excellent and good effect of anterior approach was more than that of posterior approach for 1.18(-0.48, 2.85);there were significant differences in operative time, intraoperative blood loss, correct degree of Cobb angle, loss of Cobb angle at final fol ow-up and al ograft fusion time between anterior and posterior approaches (P<0.01). The results showed that there were significant differences in operative time, intraoperative blood loss, correct degree of Cobb angle, loss of Cobb angle at final fol ow-up and al ograft fusion time between anterior and posterior approaches for the treatment of spinal tuberculosis, but there were no significant differences in total hospital stay and surgical efficacy.

Objective To explore whether apply selective perineal skin preparation or not is feasible for patients with coronary heart disease (CHD) before percutaneous coronary intervention (PCI).Methods Divided patients with CHD before PCI into the experimental group (801 cases) and the control group(798 cases) according to the hospital number.Selective perineal skin preparation was used in the experimental group,while the right forearm skin preparation was used in all the patients in the control group.The rate of skin preparation and the care hours in the two groups were compared.Results The care hours of skin preparation in the experimental group was (5.58±0.30) h,which was significant shorter than that in the control group,(66.50±1.50) h,t=-1127.03,P＜0.05.Conclusions Before PCI,for patients with CHD,applying selective perineal skin preparation is feasible.It can not only reduce care labor,decrease nursing costs,but also relieve nurse-patient psychological pressure,cut back patients' expenses;and without percutaneous entrance infection.

BACKGROUND:Nowadays, gene therapy has become a new trend for disease therapy and brought promise for some refractory diseases. Its key is to choose proper cel s, genes and vectors. OBJECTIVE:To use recombinant adeno-associated virus mediatedβ-nerve growth factor (β-NGF) to transfect rat bone marrow-derived endothelial progenitor cel s in vitro, and to investigate the effect ofβ-NGF expression on the proliferation of endothelial progenitor cel s. METHODS:The endothelial progenitor cel s were isolated, cultured and identified from the bone marrow of rats. Empty vector or recombinant adenovirus-associated virus containingβ-NGF gene was transferred into endothelial progenitor cel s. We examined the transfection efficiency by fluorescence expression of green fluorescent protein. Expression ofβ-NGF protein was detected using ELISA, and its effect on the proliferation of endothelial progenitor cel s was determined using MTT method. RESULTS AND CONCLUSION:Rat endothelial progenitor cel s were isolated and cultured successful y in vitro and were identified positive by the function of cel s and immunofluorescence staining. The endothelial progenitor cel s were infected directly by the recombinant adenovirus-associated virus containingβ-NGF gene with an efficiency of 65.3%.β-NGF protein was detected in the culture supernatant of transfected endothelial progenitor cel s, which reached a high level at 10 days after gene transfection. Furthermore, there was noβ-NGF protein in the blank and empty vector groups. After transfection, the proliferative ability of endothelial progenitor cel s was increased, which was significantly higher than the blank and empty vector groups (P<0.05). But there was no difference between the latter two groups (P>0.05). These findings suggest that recombinant adenovirus-associated virus containingβ-NGF gene can be successful y transferred into rat bone marrow-derived endothelial progenitor cel s and promote the proliferation of endothelial progenitor cel s.

Objective To assess the effect of altitude hypoxia on the elderly patients with coronary artery disease (CAD). Methods Three subject groups were surveyed during their train trip on the highest railroad--the Qinghai-Tibet Railway: 22 elderly individuals with documented CAD, 20 healthy elderly controls, and 20 healthy young controls, all of whom from Beijing near the sea level (76 m). Survey questions addressed clinical features of their healthy conditions and aspects of their coronary disease. The baseline study was performed at Xining at an altitude of 2261 m, and then during acute exposure to altitudes of 2808 m, 4768m, 5072 m and 4257 m by train for 24 hours. Resting pulse rate, blood pressure, oxygen saturation, electrocardiograph (ECG), and cardiac work estimated by the heart rate-blood pressure double product were obtained five times in each subject at different altitudes. Results On arrival to altitudes between 4768 m and 5072 m, the older passengers, especially those with preexisting coronary disease, had higher HR, higher BP, and lower SaO2, as well as more frequent abnormalities on ECG, as compared to the younger healthy subjects. As compared with the healthy elderly controls, incomplete right bundle branch block, left ventricular hypertrophy, and ST segment depression were more frequently seen in the elderly coronary patients (P<0.01). Cardiac work in group 1 was increased by 13% 12 hours after arrival to altitudes between 2808 m and 5072 m. Oxygen saturation decreased significantly with the altitude increasing by train ascent but improved after inhalation of oxygen. Most of the older subjects tolerated their sojourn at high altitude well except one who developed angina repeatedly with a significant ST segment depression. Conclusions Coronary events and ECG signs of myocardial ischemia are rare in elderly individuals with CAD who travel from sea level to moderate altitudes of 1500m to 2800 m. Patients with CAD who are well compensated at sea level generally tolerate this moderate altitude well. However, it would be prudent for patients with CAD going to altitude above 3000 m. The patients should consult their physician before undertaking a trip to such altitude.

BACKGROUND:Cold trypsin digestion is rarely reported to culture umbilical cord mesenchymal stem cells. OBJECTIVE:To compare the biological characteristics of umbilical cord mesenchymal stem cells cultured by cold trypsin digestion and tissue explant method. METHODS:Human umbilical cord mesenchymal stem cells were isolated, purified and passaged using cold trypsin digestion and tissue explant method, and then the first adhesion time and cellcycle were recorded. Morphology of umbilical cord mesenchymal stem cells was observed under inverted phase contrast microscope to draw growth curve of cells at passage 3. Flow cytometry was used to detect the surface markers of passage 3 umbilical cord mesenchymal stem cells, and Nestin expression was detected in passage 3 cells after 3 days culture in neural induction medium by fluorescence immunochemistry staining. RESULTS AND CONCLUSION:These two methods were both successful to harvest umbilical cord mesenchymal stem cells, but the first adhesion time was earlier in cells cultured by cold trypsin digestion than tissue explant method (P<0.05), and there was no difference in primary cellcycle (P>0.05). Under the inverted microscope, cells grew adherently and presented fibroblast-like shape. However, the minority of primary cells under induction of cold trypsin digestion was polygonal, irregular, and had larger cellvolume than those cultured by tissue explant method. Passage 3 cells cultured by tissue explant method showed faster proliferation rate than those cultured by cold trypsin digestion, and at logarithmic growth phase, cells cultured by these two methods were significant different in cellnumber (P<0.05). Two types of cells had a uniform cellphenotype, both of which expressed CD29, CD105, but did not express CD34, CD45. Under induction, passage 3 cells cultured by these two methods were both positive for nestin. These findings indicate that these two methods can both be used to culture umbilical cord mesenchymal stem cells, but the tissue explant method is more suitable for culture of umbilical cord mesenchymal stem cells and exhibits less damage to cells.

BACKGROUND:EdU is a new nuclear marker, and currently, it is rarely reported.
OBJECTIVE: To determine the optimal concentration of EdU to label human umbilical cord mesenchymal stem cels.
METHODS: Human umbilical cord mesenchymal stem cels were isolated, purified and subcultured. Cel morphology and growth were observed under inverted microscope. Flow cytometry was used to identify cel surface markers, as wel as adipogenic identification. EdU at concentrations of 5, 10, 20, 50, 100 μmol/L was used to label human umbilical cord mesenchymal stem cels for 24 hours. The optimal concentration that resulted in the highest labeling efficiency was selected, and then cel proliferation curve was drawn.
RESULTS AND CONCLUSION:Under the inverted microscope, cels grew adherently in a long spindle shape, and EdU-labeled cels had the same morphology. Flow cytometry showed that cels were positive for CD44, and had adipogenic differentiation ability. When the concentration of EdU was 5 and 10 μmol/L, the labeling efficiency was the highest, indicating that 5 and 10 μmol/L are the optimal concentrations of EdU to label human umbilical cord mesenchymal stem cels.