Pediatric acute respiratory distress syndrome (PARDS) is one of the most severe disease in pediatric critical care medicine with high mortality.Pediatric practitioners have recognized that ARDS in children is different from ARDS in adults.In the absence of identification of these differences,however,children have been characterized as having ARDS based on the adult definitions.Therefore,the managements for PARDS were conducted without specific considerations of children,and have limitations when applied to patients.With the purpose to highlight the gaps of ARDS between children and adults,the new insights into PARDS on the epidemiology,pathophysiology,diagnosis,treatment and prognosis in the recent years were summarized.

Objective To discuss the prevention and treatment of hemorrhage during or after minimally invasive percutaneous nephrolithotomy (PCNL). Methods Clinical data of 12 cases of hemorrhage during or after minimally invasive percutaneous nephrolithotomy from July 2005 to October 2005 in this hospital were retrospectively analyzed. Results Intraoperative hemorrhage occurred in 10 cases. The bleeding was stopped by pressure in 6 cases and a re-operation of open nephrolithotomy 5 days later was required in 4 cases. Postoperative hemorrhage was seen in 2 cases. The bleeding was successfully stopped by endoscopic electrocoagulation in 1 case and by interventional highly-selected embolization on the 4th day after operation in 1 case. Conclusions Prevention should be put first for hemorrhage during or after minimally invasive percutaneous nephrolithotomy. Accurate puncture and skillful tunnel expansion are the key to minimize the hemorrhage. Interventional embolization should be the first choice in case of massive or repeated bleeding.

Objective To evaluate the role of haeme oxygenase-1 (HO-1) in remote limb ischemic preconditioning (RLIP)-induced attenuation of lung ischemia-reperfusion (I/R) injury in rabbits.Methods Twenty-four Japanese White Rabbits,aged 4-5 months,weighing 2.0-2.5 kg,were randomly divided into 4 groups (n =6 each) using a random number table:sham operation group (S group),I/R group,RLIP group and zinc protoporphyrin (ZnPP,an inhibitor of HO-1) plus RLIP group (ZnPP + RLIP group).Lung I/R was produced by 60 min occlusion of the left lung hilum followed by 180 min of reperfusion in I/R,RLIP and ZnPP + RLIP groups.RLIP and ZnPP + RLIP groups received 3 cycles of 10 min ischemia followed by 10 min reperfusion in the bilateral hind limbs immediately before occlusion of the left lung hilum.In ZnPP + RLIP group,ZnPP 10 μmol/kg was injected intravenously 10 min prior to hind limb ischemia and the rest of the procedures were similar to those previously described in RLIP group.At the end of reperfusion,arterial blood samples were collected for blood gas analysis.The animals were then sacrificed and pulmonary specimens were obtained for microscopic examination of the pathological changes which were scored (lung injury score,LIS) and for determination of wet/dry lung weight ratio (W/D ratio),myleoperoxidase (MPO) activity,malondialdehyde (MDA) content and expression and activity of HO-1 in the lung tissues.Results Compared with group S,PaO2 was significantly decreased,and LIS,W/D ratio,MPO activity,MDA content,and HO-1 expression and activity were increased in I/R group (P ＜ 0.01).Compared with I/R group,PaO2 and HO-1 expression and activity were significantly increased,and LIS,W/D ratio,MPO activity and MDA content were decreased in RLIP group (P ＜ 0.01).Compared with RLIP group,PaO2 and HO-1 expression and activity were significantly decreased,and LIS,W/D ratio,MPO activity and MDA content were increased in ZnPP + RLIP group (P ＜ 0.01).Conclusion RLIP up-regulates HO-1 expression and enhances HO-1 activity,thus reducing lung I/R injury in rabbits.

Objective To construct eukaryotic expression plasmid pIRESneo3-pigment epithelium-derived factor (PEDF) and detect its transient expression in SP2/0 cells. Methods Specific primers were designed based on the mature peptide sequence of human PEDF cDNA in the GenBank. Human PEDF gene was cloned into the eukaryotic expression vector pIRESneo3. The PEDF DNA was transfected into SP2/0 with LipofectamineTM 2000. The recombinant human PEDF protein expressed in SP2/0 cell culture supernatant was identified by Western blot and enzyme-linked immunosorbent assay. The biological activity of the recombinant human PEDF was measured by 3-(4,5-dimethylthiazol-z-y1)-2,5-diphenytetrazolium bromide(MTT) method. Results PCR amplification, restriction enzyme digestion and DNA sequencing confirmed that the mature peptide sequence of human PEDF cDNA was successfully cloned into the eukaryotic expression vector pIRESneo3. And the plasmid was transfected into SP2/0 cells, which could secret PEDF. Western blot analysis showed that there was only one obvious band at the position of relative molecular weight of 50 000, and it is equivalent to the expected value. Enzyme-linked immunosorbent assay suggested that the content of PEDF began to rise after transfection, and peaked at 36 h [(0.92±0.04) μg/ml]. The proliferation of human umbilical vein endothelial cell line was significantly inhibited by supernatant after transfection of 36 h (P<0.05). Conclusions The eukaryotic expression plasmid pIRESneo3-PEDF had been successfully constructed and active human PEDF was transiently secreted, which made a foundation for further study of stable expression and purification of PEDF. This protein could be a potential medication for preventing and managing retinopathy of prematurity.

BACKGROUND:Many studies have confirmed that recombinant human bone morphogenetic protein 2 plays a very important role in bone formation and fracture healing, but recombinant human bone morphogenetic protein 2 alone implanted is prone to diffusion and degradation, which is unable to play a persistent role in new bone formation. OBJECTIVE:To explore the effect of recombinant human bone morphogenetic protein 2 composite bone in the rabbit lumbar fusion. METHODS:Thirty New Zealand white rabbits were selected to make posterior lumbar intertransverse fusion models, and then were randomly divided into three groups, in which, L5-6 intertransverse implantation of autologous iliac bone, al ogeneic bone and recombinant human bone morphogenetic protein 2 composite bone (recombinant human bone morphogenetic protein 2 and al ogeneic bone complex) was done respectively. At 6 weeks after implantation, gross observation, X-ray examination and histological observation were performed. RESULTS AND CONCLUSION:Fusion rate and percentage of new bone area were higher in the composite bone group than the autologous iliac bone and al ogeneic bone groups (P<0.05);the tensile strength was lower in the al ogeneic bone group than the other two groups (P<0.05), but there was no difference between these two groups except the al ogeneic bone group. X-ray films showed cal us formation in the implanted region of the three groups. In the autologous iliac bone group, a large amount of cartilage tissues formed along with a smal amount of bone trabeculae and a certain amount of woven bones. In the al ogeneic bone group, the implant was covered with a large amount of fibrous tissues, bone island was seen and there was also a smal amount of bone trabeculae and cartilage tissues. In the composite bone group, a great amount of bone trabeculae and cartilage tissues were visible to form woven bone and cortical bone. These findings indicate that the recombinant human bone morphogenetic protein 2 composite bone can obtain good effect in the rabbit lumbar fusion.

BACKGROUND:Posterior maleolar fracture is an important factor affecting the prognosis of ankle fractures. Posterior maleolar fracture often caused by high energy trauma. Using what kind of fixation and fixation materials biomechanics, and how to embed has become a current research hotspot. OBJECTIVE:To compare the clinical outcomes of different fixation materials on posterior maleolar fracture, and analyze the effect of different fixation methods on biomechanical outcome of posterior maleolar fracture fixation, so as to provide a basis and reference of selecting the best fixation for the clinical treatment of ankle fracture. METHODS: The relevant literature included by PubMed database and the China National Knowledge database from the year of 1976 to 2015 were retrieved by the first author through computer. English key words are “Ankle fracture; internal fixation; biomechanics; biocompatibility”, Chinese language search terms are “posterior maleolar fracture; internal fixation; biomechanics; biocompatibility”. Summarize the most commonly used metal fixation materials and absorbable content materials. The clinical commonly used metal fixation materials including bone plate and screws, absorbable fixation materials such as biodegradable material polylactic acid, polyethylene plastic ester, polylactide gum ester, etc. The biomechanical properties were analyzed. RESULTS AND CONCLUSION: The new locking screw can withstand more buckling and shear force. Lag screw has a tapping action, and the puling was stronger after tapping, but for patients with osteoporosis, the pressure effect of screw on fracture fragments was limited, the strength was not enough, at this time, locking plate should be used. Locking plate has a greater stability and higher confrontational feature to bending stress, less likely to pul out. Steel coupling screw provides better stability. To avoid secondary removing of the fixation, stress protection after fixation and other shortcomings after the metal material fixation fracture healing, the strength of the absorbable fixation material made by biodegradable material polylactic acid, polyvinyl acetate glue and polypropylene plastic ester after high temperature and pressure processing was increased. Absorbable fixation material may overcome the adverse effects associated with metal fixation, such as imageological examination, secondary implant removal. These results show that the mechanical properties of the absorbable screws are more closer to human bone, no surrounding bone vulnerability due to stress shields, no osteoporosis occurs, and can degrade in the body, but its fixation strength is stil less than the traditional fixed screw and bone plate. We should choose a suitable fixation material according to the forces of fracture site and the size of the fracture fragments.

BACKGROUND: In repair of nerve defect with allogenic nerve graft, to reduce immune rejection is one of the key problems. At present, the main approach is to reduce antigenicity of grafted nerve segment and apply generally immune inhibitor.OBJECTIVE: To observe the effects of freeze/thaw treatment and local application of transforming growth factor beta 1 (TGF-β1) plasmid on frozen nerve allograft.DESIGN: Randomized controlled animal experiment was designed.SETTING: Department of Hand Surgery, Union Hospital, Tongji Medical College Affiliated to Huazhong University of Science and Technology.MATERIALS: The experiment was performed in Tongji Medical College of Huazhong University of Science and Technology from January 2003 to December 2004, in which 40 Wistar healthy and adult rats were employed,from different delivery and were randomized into experimental group and control, 20 rats in each one.METHODS: Transforming growth factor-β1 (TGF-β1) plasmid and frozen allogenic sciatic nerve were prepared. In experimental group and control,sciatic nerve was cut off 2.0 cm in length, in the foramen 0.5 cm beneath piriformis. The nerve defect was repaired with pre-frozen allogenic nerve 2.0 cm in length. In experimental group, TGF-β1 plasmid was injected in local muscle and two broken ends of nerve. In the control group, physiological saline of equal volume was injected. In the 6th and 12th weeks, the samples were collected from 10 rats in each group for sectioning, staining,axonal counting and statistical analysis.RESULTS: No any animal was died in experiment and all of animals entered result analysis. In the 6th weeks, in the control group, mild edema appeared among axons on the grafted segment of nerve and in the experimental group, there was no edema among axons and the regenerated nerve numbers were close to the normal. In the 12th week, in the experimental group, the entire grafted nerve segment was basically filled up by the regenerated axons;myelinated nerve fiber was arranged in order and both axons and myelins were developed well. The regenerated axonal count in experimental group was more significantly than the control, indicating extremely significant difference [(98.6±4.8), (75.8±5.1) counts/μm2, t=2.962, P ＜ 0.01].CONCLUSION: Freeze/thaw treatment can decrease antigenicity of allogenic nerve, which provides the possibility of repair of nerve defect. Local application of TGF-β1 plasmid can provide immune inhibition locally and reduce immune rejection in the host.

BACKGROUND: At present, the repair by means of suture is still commonly used to repair the peripheral nerve injury and rupture, while the adhesion of the fibrin glue repairing peripheral nerve injury has been considered as a new topic of study.OBJECTIVE: To study the countertraction intensity of peripheral nerve and its dynamic changes after repaired with the adhesion of fibrin glue.DESIGN: A randomized controlled experimental study.SETTING and MATERIALS: The study was completed in the Laboratory of Biodynamics, Department of Orthopaedics, Union Hospital of Tongji Medical College, Huazhong University of Science and Technology. The healthy adult male Wistar rats weighing 250- 300 g were selected for the experiment.INTERVENTIONS: Totally 96 Wistar rats were completely randomized into the suture group and the adhesion group. Their sciatic nerves were cut, and the incisions were well lined. The fibrin glue was adopted in the adhesion group, while 11 -0 suture was adopted in the suture group. On the very day and 3, 7, 14, 21, 28 days after the operation, 8 rats were respectively taken each from the suture group and the adhesion group. The free sciatic nerves of them were detected immediately by the biodynamic test.MAIN OUTCOME MEASURES: The peak load and the power consumption were measured when the nerves ruptured and the nerve stress-strain curve was described.RESULTS: In normal countertraction intensity curve of the nerve, the elastic peculiarity can be manifested. Between the suture group and the adhesion group, there were no notable significances of the maximal countertraction intensity and power consumption on the very day and 14, 21, 28 days after the operation( P ＞ 0.05). While 3 days after the operation, the maximal countertraction intensity of the two groups was(1.35± 0. 27),( 1.97 ± 023) N/mm2 respectively, the power consumption was (0. 028 ± 0.007), (0.040 ± 0.003) J/mm2 respectively. Seven days after the operation, the maximal countertraction intensity was( 1.93 ± 0.26), (2.74± 0.30) N/mm2 respectively, the power consumption was(0.047±0.009), (0.063±0.007) J/mm2 respectively. The differences both had the notable significance ( P ＜ 0.05).CONCLUSION: The fibrin glue has enough countertraction intensity and can gratify the need of such nerve repairs.

Objeetive To investigate the outcome of microvascular reconstruction of the tongue with anterolateral thigh flaps in the treatment of middle-late stage tongue cancer patients. Methods From December 2003 to March 2007,nine patients underwent simultaneous reconstruction of the tongue and oral floor defects with anterolateral thigh flaps after resection of squamous cell carcinoma of tongue.The flaps ranged from 7 cm×10 cm to 10 cm×12 cm in size,and were adjusted to the defect of the tongue and oral floor.The vascular pedicle included descending branch of the lateral femoral circumflex artery and the accompanying veins.The outcome of reconstruction was evaluated by follow-up examinations,considering the contour and mobility of the reconstructed tongues,the swallowing function and the speech function.Results All of the donor sites were closed directly,with minimal donor-site morbidity. All patients recovered unevenffully from surgery,with no immediate postoperative complications:no flap necrosis,no wound infection or wound dehiscence.The transplanted flaps survived well.The average follow-up period was 18 months.During the follow-up period there was no tumor recurrence and the contour of the reconstructed tongues showed sufficient bulk.The patients demonstrated good mobility of the reconstructed tongue.The swallowing and speech function recovered satisfactory.Two months postoperatively the patients were able to ingest a solid or semisolid diet,and six months postoperatively the patients developed intelligibe language.Conclusion The anterolateral thigh flaps are suitable and reliable for the microsurgical reconstruction of the large defects caused by middle-late stage tongue cancer.

Objective To explore the advantages and disadvantages of ultrasound guided puncture microwave ablation and traditional surgical treatment of nodular goiter.Methods From January 2014 to June 2015,102 cases of nodular goiter who were treated in the Traditional Chinese Medicine Hospital of Gaozhou Affiliated to Guangzhou University of Traditional Chinese Medicine were randomly divided into two groups,51 cases in each group.Respectively by ultrasound guided puncture nodules of thyroid swollen microwave ablation (microwave ablation group) and traditional operation type removed most of the thyroid nodules (traditional surgery group) in the treatment of containing.The amount of bleeding,operation time,hospital stay,medical cost,clinical efficacy,postoperative complications and the degree of pain,and thyroid function were compared between the two groups.Results The amount of bleeding,operation time and length of hospital stay in the microwave ablation group were better than those in the traditional operation group((2.02±0.79) ml vs.(28.24±18.49) ml,(34.20 ±9.60) min vs.(75.59±25.41) min,(3.55± 1.05) d vs.(10.27±2.68) d),the medical cost of the microwave ablation group was higher than that of the traditional operation group((14 341±593) yuan vs.(5 812±970) yuan),the differences were statistically significant (t =-10.12,-10.88,-16.68,53.54;P ＜0.01).There were significant difference in terms of the postoperative pain and complications between the groups (x2=50.86,13.22;P＜0.01).The total absorption rate was 100％ in 18 months after the ablation of the nodule.There was no significant difference about postoperative residual small nodules between the two groups(P ＞0.05).Conclusion Compared with the traditional treatment,the microwave ablation treatment of nodular goiter with less complications,is a new technique of minimally invasive,beauty,safe and feasible,the exact clinical effect,and worthy of popularization and application.