BACKGROUND:Recent studies have shown that adipose-derivedmesenchymal stem cells (ADMSCs) not only have multilineage differentiation potential, but also exert an important role in blood sugar balance and hormone production.OBJECTIVE:To observe the differentiation potential of human ADMSCs (hADMSCs) into functional islet-like cells and the therapeutic effect of hADMSCs transplantation in diabetic rats.METHODS:PDX-1 gene was transfected into hADMSCs by adenovirus. Cell differentiation and insulin secretion were identified and detected by dithizone staining and ELISA, respectively. Twenty male Sprague-Dawley rats were randomly divided into control group (n=4), diabetes group (n=8) and transplantation group (n=8). Rats in the latter two groups were subjected to making diabetic models by 65 mg/kg streptozotocin injection. Afterwards, rats in the transplantation group were given PDX-1 transfected ADMSCs via the tail vein.RESULTS AND CONCLUSION:At 15 days after transfection, the number of insulin positive cells and insulin secretion were both increased significantly (P < 0.05). Fasting glucose levels in the transplantation group decreased significantly (P < 0.05), while the body weight increased significantly (P < 0.05). In the diabetic group, the fasting glucose level still maintained at a high level, and the body weight of rats was significantly decreased. These results implicated that PDX-1 gene could induce hADMSCs differentiating into functional islet-like cells. PDX-1 transfected ADMSCs transplantation is effective in treating diabetic rats, but the mechanism needs further study.

BACKGROUND:Experiments have demonstrated that biological membranes can be usedtorecon struct thetendon she athandin hibit exogenou shealing of thetendon.Therefore,the semembrane sprovide a good bed for tendon gliding and reduce tendon adhesion.
OBJECTIVE:To compare the effectsof acelular amniotic membrane and medical membraneagainst tendon adhesion during the repair oftendon sheath defects.
METHODS:ToesIIIfrom the bipeds of 66 leghorns were chosen to prepare tendon injury and tendon sheath defect models, which were randomly divided into three groups (n=22 per group). Amnion group were repaired with acelular amniotic membrane, medical membrane group with absorbable membrane, and control group had no treatment on tendon sheath defects. Gross, histological and biomechanical tests of each group were performed at 2, 4, 8, 12 weeks after surgery.
RESULTS AND CONCLUSION:At 12 weeks after surgery, in the amniotic membrane and medical membrane groups, the tendon sheath formed completely, and the tendon healed well, with no adhesion, but in the control group, there was serious tendon adhesion. At 8 weeks after surgery, the number of synovial cells in the false sheath was highest in the amniotic membrane group sequentially followed by the medical membrane group and control group. In the amniotic membrane group, the rough endoplasmic reticulum expanded highly and secreted exuberantly in the matrix, while in the control group, the synovial cells presented with messy arrangement, and expanded vacuoles in the matrix were weaker than those in the other two groups. At 12 weeks after surgery, fibroblasts were arrayedtidily in layerwith dense structure in the medical membrane and amniotic membrane groups;but in the control group, fibroblasts were distributed disorderly with loose structure. Tendon sliding distance and total flexor toe angle in the amniotic membrane and medical filmgroups were significantly larger than those in the control group (P < 0.05),butthere was no significant difference between the medical membrane and amniotic membrane groups. Additionally, the maximum tensile fracture strength had no significant difference among three groups at 12 weeks after surgery. These results indicate that both amniotic membrane and medical membrane can markedlyprotect the tendon from exogenous healing and adhesion.

BACKGROUND:To improve local microenvironment and reduce local scars is conducive to peripheral nerve regeneration that promotes nerve function recovery.OBJECTIVE:To evaluate the effect of fresh amniotic membrane on the regeneration of tinjured peripheral nerve.METHODS:Sixty healthy Sprague-Dawley rats were randomly divided into three groups (n=20 per group) after constructing a model of sciatic nerve injury of the unilateral leg. In group A, the nerve was wrapped with fresh human amnion at the anastomosis end after the repair of nerve. In group B, the nerve was wrapped with biofilm at the anastomosis end after the repair of nerve. In group C, no treatment was conducted after the repair of nerve (blank control). The effects were evaluated by anatomical observation, light microscope observation, immunohistochemical detection (2, 4, 8, 12 weeks after surgery), transmission electron microscope observation, axon imaging analysis, action potential detection, and sciatic nerve function index (4, 8, 12 weeks after surgery).RESULTS AND CONCLUSION: (1) Gross observation. The amniotic membrane and biofilm were absorbed partialy at postoperative 2 weeks, mostly at postoperative 4 weeks and completely at postoperative 8 weeks. In the groups A and B, the nerve was adhered slightly and loosely to the surrounding tissues, with a fair range of motion. In the group C, the nerve was tightly adhered to the surrounding tissues, with a poor range of motion. (2) Observation under light microscope. The nerve regeneration was better in the groups A and B than group C at 2, 4, 8, 12 weeks postoperatively. (3) Observation under electron microscope. Regenerated nerve fibers were rarely seen and lamelar structures were unclear in the three groups at 4 weeks postoperatively. Then, increased regenerated nerve fibers, thickened myelin sheath, clear lamelar structure and enlarged axon diameter were found in the groups A and B compared with the group C at 8 and 12 weeks postoperatively. (4) Immunohistochemical detection. The expression and distribution of S-100 protein in the groups A and B were better than those in the group C. (5) Axon image analysis. Groups A and B were superior to the group C in the diameter of myelinated nerve fibers, thickness of myelin sheath and number of regenerated nerve fibers. There was a significant difference by statistical analysis (P < 0.05). (6) Electrophysiological examination. Shorter latency period, higher amplitude and faster nerve conduction velocities were observed in the groups A and B compared with the group C (P < 0.05). (7) The sciatic function index. The sciatic function index in group A or B was significantly higher than that in group C (P < 0.05). To conclude, the human amniotic membrane can reduce adhesion between the damaged nerve and surrounding tissues, and prevent scarring at the anastomosis end. In addition, it promotes the regeneration of nerve fibers, increase axon diameter and myelin sheath thickness, and ease inflammatory and immune responses at the neural incision.

Objective To investigate the effect of different sputum suction methods on the incidences of pulmonary infections in patients with mechanical ventilation.Methods Four hundred and sixty-six patients with mechanical ventilation were randomly divided into study group(n=219)and control group(n=247).The two groups were treated with continued balloon filling and airway humidification.Besides,the control group received conventional open sputum suction and the study group closed continuous negative pressure sputum suction.The two groups were compared in terms of incidence of pulmonary infections.Result The incidence of the study group(8.2%)was significantly lower than that of the control group(14.6%)(χ2=4.58,P<0.05).Conclusion Compared with the traditional open conventional sputum suction method,closed continuous negative pressure sputum suction may be more effective in reducing the incidence of pulmonary infection in patients with mechanical ventilation.

Objective To discuss the influence of bath frequency on neonatal skin condition and body temperature. Methods 108 newborns from obstetrics of People′s Hospital of Peking University during November 2015 to December 2015 were selected, and were randomly distributed t into two groups by lottery. The control group took bath every day, whereas the experimental group did every three days. The newborns were followed up for 4 weeks on their skin condition and body temperature. Then the data were systemized and performed statistical analysis. Results During the first 4 weeks after babies were born, the control group and experimental group showed no significant difference on their skin condition (P>0.05). When compared at the time of first 3 days, 1 week and 2 weeks after the babies were born, body temperature of the experimental group were (36.693±0.182), (36.738±0.174), (36.772±0.185)℃, while the control group were (36.591 ± 0.160), (36.671 ± 0.158), (36.684 ± 0.155)℃,which tended to be significantly lower than the experimental group (t values were -2.697,-2.087,-2.669, P <0.01 or 0.05), but still within the normal range. However, this difference of body temperature disappeared after the first 2 weeks (P>0.05). Conclusions Reducing the bath frequency form once a day to every third day showed no influence on neonatal skin condition. Meanwhile, it did avoid significant reduce of body temperature after bath. This may help improve healthy skin care of newborns, promote their growth, and at the same time, redistribute the clinical nursing work efficiently.