Burns ; pathology ; Humans ; Wound Healing

Objective To compare the efficiency of detecting YMDD mutations by direct DNA sequencing and real time fluerescence PCR, and to explore the significance of the mutations of drug-resistance gene other than YMDD mutation. Methods 92 serum samples from 89 patients with chronic hepatitis B were collected and all the samples were detected by real-time PCR for YMDD mutation. HBV DNA was extracted from serum and was amplified by nest PCR to achieve HBV P gene RT region sequence. The PCR products were sequenced at both directions, and the sequencing results were contrasted through NTI program. The other 11 known drug-resistance mutation sites at the HBV RT region were also analyzed. Results Among the 37 samples with no YMDD mutation detected by real-time PCR, 33 samples were with M204M (without mutation), 1 sample with M204I and 3 samples with M204V by direct sequencing. Mutation and wild-type standard sequences were all coexisted in the 4 positive samples. There were 7 samples detected with ADV resistant mutation, accounting for 18.9% (7/37). Among the 55 samples with YMDD mutation detected by real-time PCR, 52 samples were detected by DNA sequencing, the accordance rate was 94.5% (52/55); 5 samples with ADV or ETV resistant mutation were detected, accounting for 9.1% (5/55). Conclusions Direct DNA sequencing is a high sensitive, repeatable method to detect drug-resistance mutation at RT region of HBV P gene. The result is well consistent with that attained by real-time PCR. Direct DNA sequencing can also detect various drug-resistance mutations as well as YMDD mutation, which is helpful to generally understand the nucleoside analogue resistant mutation and adopt more reasonable therapy projects against HBV.

[Objective]To study the effect of repairing of rat peripheral nerve defect with engineering artificial nerve composed with Schwann cells and poly lactic glycoli aced(PLGA).[Method]Human Schwann cells were vaccinated into PLGA tube with polyglactin 910.Sixty SD rats were divided into 3 groups randomly with 20 rats in each one: group A,self-nerve graft;group B,Schwann cells artificial nerve;group C,pure PLGA.Evaluations of electrophysiological and histological examines were carried out 8 weeks ad 12 weeks after operation.[Result]The outcome of group B showed similar to group A in general and histological study,however it expressed slightly lower in electrophysiological study,muscle weight and nerve fiber quantity.Marked neuron could be found in spinal cord after group B had been traced.Large number of regeneration nerve fibers could be seen from electron microscope.[Conclusion]The tissue engineering artificial nerve composed with Schwann cells is able to repair 20 mm defects of peripheral nerve,and it has an approximate treatment effect to the self-nerve grafting.

[Objective]To explore the indications and operative techniques for comminuted fracture of proximal humerus. [Method] Twelve patients with fracture of proximal humerus were chosen, observation was made after locking proximal humerus plate fixation with anterior acromioplasty. [Result]The average follow-up period were 12 months (6～24months). All patients' fracture in surgery group had been union and all shoulder had good functions. No incidence of avascular necrosis and nonunion was found. [Conclusion]Rigid fixation of displaced comminuted fractures of proximal humerus with anterior acromioplasty is a simple and effective technique to prevent subacromial impingement syndrome after surgery. Precise osteotomy and early postoperative exercises are the key to success.

The basic concept of gene therapy is to introduce a therapeutic gene into a cell, whose expression can improve to healing of wound. To achieve this goal, the suitable therapeutic gene has been selected and delivered into the reparative cell, which is becoming a focal point works about gene therapy in wound healing. There have been several different therapeutic genes and gene transfer strategies that have been used in models of wound healing. This article discusses several methods that have been used to deliver genes encoding growth factor proteins, stem cells into wounds and the advantages/disadvantages of each approach. We hope a safe vectors system to deliver the effectual transgene in wound healing.

Objective To observe the expression of both type 1 (AT1) and type 2 (AT2) receptors of angiotensin Ⅱ (AngⅡ) in human hypertrophic scars, and to explore theirs role in collagen synthesis of fibroblasts in human hypertrophic scars. Methods The expression of both AT1 and AT2 receptors in fibroblasts of hypertrophic scars was detected with immunohistochemical staining and radioligand receptor binding assay. Collagen synthesis was examined in cultured in vitro fibroblasts of hypertrophic scars by measuring [~3H]proline incorporation into collagenous proteins. Results Positive staining signals of both AT1 and AT2 receptors were found in fibroblasts of hypertrophic scars. Similar results were also got in cultured in vitro fibroblasts of hypertrophic scars, expression level of AT1 and AT2 receptors were 10.69?2.15fmol/10~6cells and 4.9?1.05fmol/10~6cells respectively. In cultured in vitro fibroblasts, AngⅡ may accelerate the collagen synthesis significantly (P

To investigate the effects of basic fibroblast growth factor (bFGF) on intracellular free Ca 2+ of heating injury, and observe the relationship between mitogen activated protein kinases(MAPKs)signal pathways and Ca 2+ mobilization. Cultured human fibroblasts were heated at 45?C for 10min, then divided into four groups :①basic fibroblast growth factor (10ng/ml) treatment; ②preincubated cells with PD98059 (10?mol/L) for 30 min followed by bFGF (10ng/ml); ③preincubated cells with SB203580 (10?mol/L) for 30min followed by bFGF (10ng/ml); ④preincubated cells with PD98059 (10?mol/L) and SB203580 (10?mol/L) for 30min followed by bFGF (10ng/ml). The cells were incubated with fluorescence Ca 2+ dye fluo 3/AM at 37 C for 30min, then measured by using laser scanning confocal microscope. The results showed fluorescent intensity of fibroblast heating injury was weak, the concentration of intracellular free Ca 2+ increased after stimulation with bFGF treatment. PD98059 and SB203580 could induce calcium oscillation. A rapid decrease of fluorescent intensity was observed after cells were preincubated with PD98059 and SB203580 at the same time. bFGF induced an increase of cytoplasmic and intracellular free Ca 2+ concentrations. It is suggested that MAPKs signaling pathway has a feedback regulation for free Ca 2+ mobilization.

Objective To investigate the diagnostic and therapeutic methods of small intestinal hemorrhage.Method Clinical data of forty-nine cases of small intestinal hemorrhage were analyzed retrospectively.Results Small intestinal tumors were found in 21 cases (42.9%),among wtich,most were benign;infectious diseases in 12(24.5%);diverticula's in 8(16.3%);and vascular malformations in 6(12.2%).Radionuclide scanning was positive in 10 out of 13 cases (76.9%).Angiography was performed in 12,7 of them were abnormal (58.3%).Small bowel series made diagnosis in 25% of 36 cases.Postoperative bleeding was found in 5 cases and short bowel syndrome in 1 case.Conclusions Tumors are the most common cause of small bowel bleeding,and acute hemorrhagic nercotizing enteritis and typhoid often cause small bowel massive bleeding.Radionuclide scanning is one of the most useful diagnostic methods for diverticula's.Angiography is a valuable procedure in diagnosis of vascular lesions and malignants.Small bowel series is also helpful in diagnosis of solid lesions and diverticula's. Exploratory surgery coupled with intraoperative endoscopy can be helpful in diagnosis of small bowel bleeding.

To explore the activities of signal transduction pathway involved in heat-stressed fibroblast in vitro. Human dermal fibroblasts were cultured in Dulbecco′s modified Eagle′s medium with 5% calf serum at 5%CO 2 in a water-saturated atmosphere. Cultured cells were heated to 45℃ for 10min. Western blotting was used to detect ERK1/2 and JNK expression, and the expression of caspase-3 protein was observed by immunoflurescence technique. The results showed that the MAPKs signal transduction pathway was activated in heat-stressed fibroblasts. The expression of JNK reached the peak at 60min, then maintained up to 180min. The expression of ERKs peaked at 30min, then lowered. The expression of caspase-3 was weak at 30min after heat-stress, and became evidently strong at 60min. The signal pathway of ERKs and JNK played important roles in the changes in biologic characteristics of fibroblasts after heat-stress.