BACKGROUND:Chitosan is wel known as good biocompatibility and biodegradability;however, its extensive use in biomedical applications is restricted due to its poor transfection efficiency. OBJECTIVE:To prepare the polyethyleneimine-chitosan/DNA nanoparticles loading enhanced green fluorescent protein gene, and to detect their physicochemical properties and gene transfection efficiency towards chondrocytes in vitro.
METHODS:Low molecular weight polyethyleneimine was covalently linked to chitosan backbone to construct chitosan-graft-polyethyleneimine;then the chitosan-graft-polyethyleneimine was mixed with DNA nanoparticles, which loaded enhanced green fluorescent protein gene, by a complex coacervation method. The nanoparticle morphology was observed under a scanning electron microscopy. The sizes and zeta-potentials of the
nanoparticles were measured by a Marven-nano laser diffractometer. The binding capacity of plasmid DNA was evaluated by agarose gel electrophoresis analysis. The gene transfection experiments in vitro were performed towards rabbit’s chondrocytes. The gene transfection efficiency was measured with flow cytometry and under fluorescence microscope. How marked DNA entered into the nucleus of chondrocytes mediated by the nanoparticles was detected by laser scanning confocal microscopy.
RESULTS AND CONCLUSION:The prepared nanoparticles were mainly spherical, with an average size of (154.6±18.6) nm, and zeta-potential of (24.68±6.82) mV. The agarose gel electrophoresis analysis confirmed that the nanoparticles could effectively protect plasmid DNA from DNase Ⅰ-induced degradation. Gene transfection in vitro proved that the nanoparticles were efficient in transfecting rabbit’s chondrocytes and the expression of green fluorescent proteins was observed under fluorescent microscope, with a transfection efficiency of (23.80±1.74)%that was significantly higher than that of the naked plasmid DNA and chitosan/DNA nanoparticles (P<0.05). But no significant differences were observed between polyethyleneimine-chitosan/DNA nanoparticles and LipofectamineTM 2000. These findings indicate that the polyethyleneimine-chitosan/DNA nanoparticles can effectively protect plasmid DNA from nuclease degradation, and exhibit the favorable transfection ability towards articular chondrocytes.

Objective To comparison anterior cervical decompression and plating techniques for CSM between under microscope and traditional method retrospectively, investigate clinical result of surgery under microscope. Methods Sixty-seven patients with CSM underwent surgery of anterior cervical decompression and plating techniques were evaluated retrospectively from January 2008 to June 2010. Thirty-three patients underwent operation under microscope; thirty-four patients underwent traditional operation. The operating time, bleeding volume during operating and poster operating, walking time post-operation and complication were observed. Clinical outcomes were assessed by Japanese Orthopaedic Association (JOA), Image of before and after operation. Results Microsurgery operation time averaged of 100 minutes. Bleeding volume during the operation averaged of 60 ml, and after operation averaged of 40 ml. The JOA scores were improved from 8.43 pre-operatively to 14.70. Six months post operation, the average rage of JOA improvement were 83.2%. Traditional operation time averaged of 115 minutes. Bleeding volume during operation averaged of 100 ml, and after operation averaged of 50 ml. The JOA scores were improved from 7.45 pre-operatively to 11.84. Six months post operation, the average rage of JOA improvement were 82.1%. There were difference between two groups(P ＞ 0.05) in the JOA scores. No statistical difference (P ＜ 0.05) in bleeding volume and operating time. Conclusion The operation under microscope is restored significantly than the traditional method in bleeding volume, the surgical field, safety of operation, time of recovery and so on.

Objective To determine the dynamic change of serum procalcitonin (PCT) level after traumatic brain injury and the rclated clinical significance.Methods Serum levels of PCT and adrenocorticotropic hormone (ATCH) in 137 patients with traumatic brain injury and 20 normal volunteers were measured by electrochemiluminescence assay.Correlation between serum PCT level and severity of traumatic brain injury was evaluated.Results Percentage of serum PCT level at low inflammatory-risk threshold detected from day 1 to day 14 after admission was descended from 80.3％ to 63.5％.Meanwhile,the percentage of serum PCT level at high inflammatory-risk threshold was a rising-fall-rising trend,but the percentages of serum PCT level at median and definite inflammatory-risk thresholds showed sustained increase from 13.9％ to 27.0％ and 0.7％ to 3.7％ separately.Based on the Glasgow Coma Scale (GCS),the dynamic change of serum PCT level demonstrated a distinct bimodal pattern in severe injury group,a gradual falling after rising mode in middle injury group which was significantly and positively correlated with GCS (r =0.463,P ＜ 0.05),and a rising-falling-slight rising tendency in minorinjury group.In addition,the GCS in each group only closely related to the positive detections of serum PCT level detected at days 3 and 7 (x2 =10.32,16.31 respectively P ＜ 0.01).Serum ATCH level at day 1 was far higher than that at day 14 in severe injury group and was significantly higher in severe injurygroup compared with minor and middle injury groups (P ＜ 0.01 or 0.05).Conclusions Positive serum PCT may be predictive of the traumatic brain injury and injury degree within 3-7 days after the injury.The dynamic change of serum PCT is associated with the specialized mechanism of traumatic brain injury and neuronendocrine response,and it may be a useful parameter to assess posttraumatic stress response and prognosis.

Objective To investigate the chronic angio-complications of diabetes mellitus(DM)and impared glucosetolerance(IGT)patients were diagnosticated newly.Methods 46 patients with diabetes mellitus and 97 pa- tients of impared glucosetolerance were chosen in the study,and 35 patients were chosen as normal glucose tlerance group.Some biochemical criterion,carotid artery intima-media thickness and plaque condition were measure.Results The group of IGT contract coronary heart disease is 62.9 %,cetebrovascular disease is 20.6%,carotid artery atheromatosis is 50.5 %,the group of DM contract coronary heart disease is 65.2%,cerbrovascular disease is 26,1%,carotid artery atheromatosis is 69.6%,it have statistics significance compared with control group(P

Objective To investigate the curative effects of the traditional surgical method of posterior pedicle Schanz screw fixa-tion with partially stripping injured paravertebral muscle in treating thoracolumbar fracture .Methods 52 cases with thoracolumbar fracture underwent posterior pedicle Schanz screw fixation to partially strip injured paravertebral muscle from January ,2010 to Jan-uary ,2012 .The patients were divided into partially stripping injured paravertebral muscle group (32 cases) and traditionally strip-ping injured paravertebral muscle group(20 cases) .The blood loss ,postoperative drainage ,kyphosis postoperative 3 d VAS scores , vertebral height correction rate ,Cobb angle correction ,Oswestry dysfunction indexes were copmared .Results Comparing with tra-ditionally stripping injured paravertebral muscle group ,the partially stripping injured paravertebral muscle group has better effect in transperative blood loss ,postoperative drainage and postoperative 3 d VAS scores ,the differences were statistically significant .But there was no statistical significance between the two groups in vertebral height correction rate ,kyphosis Cobb angle correction ,Os-westry dysfunction indexes .Conclusion Partially strip injured paravertebral muscle has less painful than traditional surgery does , being safe and effective with small invasion and easy to recover .

Objective To investigate the effect of chymase on the proliferation of rat cardiac fibroblasts (CFs) and the role of transforming growth factor-?1 (TGF-?_1).Methods Cultured CFs of neonatal SD rats were isolated by trypsinization.Cell number and DNA synthesis were evaluated by MTT assay (A_(490) value) and [~3H]-deoxythy- midine [~3H]-TdR incorporation.The mRNA expression of TGF-?_1 in CFs was determined by RT-PCR.Results Chymase increased CFs numbers and [~3H]-TdR incorporation in a dose-dependent manner.The A_(490) value of CFs stimulated by 15,30 and 60 ng/mL chymase was 0.263?0.033,0.348?0.031 and 0.387?0.026,respectively, which were all significantly higher than that of control (0.201?0.019,P

Animals ; Hypoxia ; classification ; metabolism ; Male ; Oxygen Consumption ; Rats ; Rats, Sprague-Dawley

Angelica sinensis ; chemistry ; Animals ; Drugs, Chinese Herbal ; therapeutic use ; Lung Diseases, Interstitial ; drug therapy ; Male ; Phytotherapy ; Pulmonary Fibrosis ; drug therapy ; Rats ; Rats, Wistar

Objective To discuss the surgical outcome of fenestration assistant by microscopy for single-level lumbar disc protrusion (LDH), compared with tradition laminotomy and discectomy. Methods From January 2008 to January 2010, forty-eight patients underwent traditional open discectomy and 40 underwent microscopy surgery. The lumbar disc protrusion involved L3- L4 level in 12 cases, L4-L5 level in 46 cases, and L5-S1 level in 30 cases; preoperative JOA score was 8-19 points (average 12.9 points) for traditional open discectomy patients and 7-19 points (average 12.7 points) for microscopy surgery patients. Results Cauda equina injury was occurred and repaired in 2 cases in traditional surgery group. The follow-up period was 10-34 months (average 18 months) for all patients. No complications such as wrong orientation, nerve root injury, and infection occurred. The JOA score 10 months after operation was (24.0 ± 2.6) for traditional surgery patients with 87.5% success rate and (24.2 ± 2.8) for microscopy surgery patients with 90% success rate. Conclusion Two methods have similar clinical outcomes, but microscopy assistant fenestration for LDH has advantages of minimal invasion, shorter operative time, shorter length of hospital stay and less intraoperative blood loss. It is one of ideal minimally invasive operations for single-level lumbar disc protrusion.

Objective To evaluate the characteristics and efficacy of microscope-assisted bilateral decompression via unilateral approach for the treatment of lumbar stenosis. Methods From June 2007 to June 2010, Sixty case lumbar stenosis with bilateral decompression were treated via unilateral approach under microscopy. Patients were followed up from 6 to 24 months, average (12 ± 4.7) months. Results The pain level of each patient was assessed both before and after the opeartion, using a visual analogue scale (VAS). Intermittent claudication was completely relieved in 57 out of 60 cases, moderately relieved in 3 cases. VAS score decreased from pre-operational 9.08 ± 0.76 to post-operational 2.33 ± 1.43, and there was significantly difference between them. There was no recurrent case during the whole follow-up. Conclusion Bilateral decompression via unilateral approach under microscope is proved to be an effective and safe procedure for the treatment of lumbar stenosis, and have the advantages of minimal invasion, less pain, quick recovery, better effect, little influence on the spinal stability.