Stem cell is one of the hot spot in the research area of biomedical engineering. Special attentions are drawn to the research and application of neural stem cells. Neural stem cells exist widely in central nervous system, which has the capacity of self-renewal and the potential to differentiate into other cells. The so-called engineered neural stem cell is constructed by using the technique of genetic engineering to make it be able to express various neural growth factors with high-performance and stability. The engineered neural stem cells have a great potential in the therapy of diseases of central nervous system, especially the spinal cord injury. This article reviews the research development of engineered neural stem cells, the problems confronted with it, and the trend for research in the future.

Titanium alloy has been used widely in fields of hard tissue replacement and repair,despite its characteristics of bio-inert material.Bio-ceramic coating deposited on Ti-based implants surface using surface modification technique can improve the bioactivity and biocompatibility of Ti-alloy material.The hydroxyapatite coating has been applied in clinic treatment,but this type of coating is still plagued with low crystallinity and poor bonding strength.In order to obtain an implant with excellent integrated properties,some novel bio-ceramic coating materials have been prepared.These materials having excellent bioactivity and biocompatibility and can directly bond with the Ti-based implants and the bone tissue.This review will present research status of the application of bio-ceramic coating on titanium alloy surface in biomedical fields

ObjectiveAnalyze preoperative clinical relevanted factors of acute type A aortic dissection with hypoxemia according to a group clinical data.MethodsFrom January 2011 to June 2011,we have collected 54 preoperative cases of acute type A aortic dissection,including 42 males,12 females,aged 28-73 years old,onset to treatment time is 0.4-14.0 days.General information:age,gender,time of onset,body mass index,hypertension,diabetes mellitus,smoking,drinking,heart ejection fraction,prothrombin time,quantitative fibrinogen,fibrinogen degradation products,D-dimer,C-reactive protein,procalcitonin,ICU time,length of hospital stay.According to the blood gas analysis of quiet state case without oxygen,with PaO2 ＜ ( 100-age ×0.33 ±5) mm Hg is for the hypoxemia group,equal or higher than this is no-hypoxemia group.ResultsNo-hypoxemia group has 14 cases,11 males,3 females,average aged (51.14 ± 14.24) years old,including 12 operation patients ( no death) and 2 no-operation patients(2 cases death).Hypoxemia group has 40 cases,31 males,9 females,average aged (50.53 ± 9.73 ) years old,including 33 operation patients(2 cases death) and 7 no-operation patients(7 cases death).There is no significant difference in age,gender,time of onset,hypertension,diabetes mellitus,smoking,drinking,cardiac ejection fraction,prothrombin time and fibrinogen.There is statistically significant on body mass index,fibrinogen degradation products,D-dimer,C-reactive protein,procalcitonin,ICU time and length of hospital stay time ( P ＜ 0.05 ).ConclusionPreoperative hypoxemia with acute type A aortic dissection is associated with obesity,excessive inflammation and activation of coagulation and fibrinclytic system,and hypoxemia may prolong the time of operative patients with acute type A aortic dissection in ICU and hospital.

Objective To investigate whether emodin(1,3,8-trihydroxy-6-methylanthraquinone) can attenuate inflammatory response in rats' lungs with acute necrotic pancreatitis (ANP). Method Acute necrotic pancreatitis model was induced by injection of 3% sodium taurocholic acid into the subcapsular of pancreas and emodin was administered by intestine perfusion. Plasma amylase of 3, 6 and 12 h with acute necrotic pancreatitis was measured together with the detection of IL-1β, IL-6 and IL-10 mRNA expressions in rats' lungs by semi-quantitative RT-PCR. Immunohistochemistry was detected the expression of IL-1β converting enzyme (ICE) in the rats' lungs. Result Plasma amylase of 3, 6 and 12 h with acute necrotic pancreatitis groups are obviously high as compared with normal group(P＜0.05). Plasma amylase was (1 611.20±218.72)IU/L in normal group. Plasma amylase of 3, 6 and 12 h with acute necrotic pancreatitis groups were (1 981.40±56.81)IU/L, (3 287.40±612.37)IU/L and (4 914.60±746.82)IU/L. Plasma amylase of 3, 6 and 12 h with acute necrotic pancreatitis after treatment with emodin groups were obviously low as compared with acute necrotic pancreatitis groups. The plasma amylase was(1 617.20±136.80)IU/L,(2 323.40±318.19) IU/L and (2 670.20±390.03)IU/L respectively. The study showed that the mRNA expression of pro-inflammatory cytokin IL-1β and the expression of IL-6, as well as the expression of IL-1β converting enzyme(ICE) were decreased and IL-10 was increased. Conclusion The study demonstrates that emodin plays an important role in reducing plasma amylase level. Emodin exerts anti-inflammatory effects in acute necrotic pancreatitis rats' lungs by downregulating the mRNA expression of IL-1β and IL-6 and upregulating the mRNA expression of IL-10.

Objective To construct a recombinant bacterial vaccine which can express specific 10-23 deoxyribozyme(DZ) in macrophage, identify the intracellular production of specific 10-23DZ and detect the activity of this recombinant bacterial vaccine on inhibiting the expression of TACO gene in macrophage.Methods The pSDE02 was obtained by inserting the replicon of Mycobacterium into pSDE01, a plasmid which can express 10-23DZ in eukaryotic cells. The expression sequence of DZ1, a 10-23DZ targeting the TACO mRNA of macrophage designed in our previous study was synthesized and inserted into pSDE02. The resulted plasmid was named pDZM01. pDZM01 was then transferred into Mycobacterium smegmatis by electroperation. The recombinant M. smegmatis, named rMs-DZ1 was screened on low-salt LB medium containing Zeocin and identified by Colony PCR. The targeted delivery property of recombinant M. smegmatis was observed by Ziehl-Heelson stain and GFP expression observation via fluorescence microscope. rMs-DZ1 was used to infect RAW264.7 cells and the expression of DZ1 in macrophage was identified by dot-blot assay. At 24 h and 48 h after infection, total RNA and proteins were extracted and the TACO mRNA and protein expression level was assayed by RT-PCR and western-blot respectively. Results Restrictive analysis and sequencing data showed that the Mycobacterium-eukaryotic cell shuttle plasmid pSDE02 and pDZM01 was successfully constructed. rMs-DZ1 was confirmed by colony PCR. When engulfed by macrophage, rMs-DZ1 would express DZ1 in RAW264.7 cells and inhibit the expression of taco gene. When compared to uninfected macrophage, rMs-DZ1 significantly reduced the taco mRNA by 67.90% and 57.14% and down-regulated the expression of TACO protein by 53.85% and 68.92% at 24 h and 48 h respectively. Conclusion A recombinant M. smegmatis vaccine was successfully constructed which could generate specific 10-23DZ in macrophage and inhibit the expression of target gene of interest. To our knowledge, this is the first bacterial vector which can express intracellularly 10-23DRz in targeted manner. This study may further prompt the feasibility of using 10-23 DNAzyme to achieve effective and targeted gene silence.

Objective To explore the safety and feasibility of performing total thoracoabdominal aortic aneurysm repair (tTAAAR) under normal thermia and non-cardiopulmonary bypass fashion by comparing surgical indications and details of different surgical strategies in tTAAAR.Methods From February 2009 to May 2011,46 consecutive patients with extensive Crawford Ⅱ thoracoabdominal aortic aneurysm (TAAA)underwent total thoracoabdominal aortic aneurysm repair( tTAAAR ) in An Zhen Hospital.The patients were divided into 2 groups ( A and B) according to their different surgical strategies.Patients in group A underwent total thoracoabdominal aortic aneurysm repair with deep hypothermia and circulatory arrest.Patients in group B underwent total thoracoabdominal aortic aneurysm repair in a normal thermia and non-circulatory bypass was performed via a combined left thoracoabdominal incision.After established the bypass from descending aorta to bilateral iliac arteries under normal thermia,the reestablishment of intercostal arteries and visceral arteries was followed with subsection circulatory arrest.The clinical results of these 2 groups were analyzed by SPSS 18.0.Results Patients in group A underwent total thoracoabdominal aortic aneurysm repair with deep hypothermia and circulatory arrest have higher mortality rate and transient nervous dysfunction rate (26.67％ vs 3.20％,P =0.033 ; 33.30％ vs 3.30％,P =0.018,respectively) than patients in group B underwent total thoracoabdominal aortic aneurysm repair in a normal thermia and non-circulatory bypass.Statistical significance was also observed between group A and circulatory arrest and group B in operation time,descending aortic clamping time,and transfusiori volume of red blood cells ( P ＜ 0.05 ).Average age,sex,pathological type,the maximal diameters of aneurysm,preoperative complications,visceral ischemia time,spinal cord ischemia time,ICU treatment time,intubation time,respiratory complications,plasma dosage,platelets dosage,RBC dosage,thoracotomy hemostatic,spinal cord injury,renal insufficiency were found no statistical significance(P ＞ 0.05 ) between two groups.In addition to death and paraplegia,the others were cured.Conclusion The normal thermia and non-cardiopulmonary bypass tTAAAR is a safe and feasible therapeutic strategy for TAAA patients.A bypass from descending aorta to iliac arteries can be built under normal thermia in TAAA patients,which is the indication of this new technique.Reestablishment of intercostal arteries is an important protective adjunct to avoid spinal cord injury.

OBJECTIVETo summarize the therapeutic effect of 5 kinds of flaps for the treatment of skin and soft tissue defect in the hallex.

METHODSFrom Jan. 2008 to Jun. 2013, 24 cases with skin and soft tissue defects in the hallex were treated with 5 kinds of reversed flaps, including medial foot dorsal neurocutaneous flaps, medial foot neurocutaneous flaps, lateral tarsal flaps, anterior malleous flaps, medial cross leg and saphenous nerve flaps. The defects size ranged from 3 cm x 2 cm to 5 cm x 3 cm, with the flap size from 3. 5 cm x 2. 5 cm to 5. 5 cm x 4. 0 cm.

RESULTSPartial superficial necroisis happened at the distal end of one foot dorsal medial neurocutaneous flap. One third flap necrosis occurred in 1 foot medial neurocutaneous flap due to too tight suture at flap pedicle and resulted thrombosis. All the other 23 flaps survived completely. 15 cases were followed up for 3-36 months with normal walking function and satisfactory appearance. Among the 8 cases with nerve anastomosis, 4 cases were followed up with 2-point discrimination distance of 8-11 mm. the flaps without nerve anastomosis also had protective sense due to nerve ingrowth.

CONCLUSIONSSkin and soft tissue defects in the hallex can be treated with different appropriate flaps. The hallex length can be reserved with satisfactory function and appearance.

Foot Injuries ; surgery ; Graft Survival ; Hallux ; injuries ; surgery ; Humans ; Necrosis ; Reconstructive Surgical Procedures ; Soft Tissue Injuries ; surgery ; Surgical Flaps ; pathology ; transplantation

Objective:To prepare PEG-SH modified GNPs/miR-29 nanoparticles and to investigate the proliferation and differentiation of neural stem cells induced by PEG-SH modified GNPs/miR-29 nanoparticles.Methods:PEG-SH modified GNPs/miR-29 nanoparticles were developed by oxidation-reduction method and were tested for UV absorption spectrum, particle size distribution and zeta potential of nanoparticles. A total of 15 adult male Sprague Dawley (SD) rats were used to establish spinal cord injury model by modified Allen method. The artificial miR-29 and PEG-SH modified GNPs/miR-29 nanoparticles were implanted into the injury site of spinal cord respectively. The stability of miR-29 expression was analyzed by gel electrophoresis. The neural stem cells were isolated and cultured from 10 SPF grade neonatal rats. It was identified by Nestin, GFAP and NSE antibodies. The activity and proliferation of neural stem cells in synthetic miR-29, PEG-SH GNPs and PEG-SH GNPs/miR-29 nanoparticles group was detected by CCK-8 assay. Neural stem cells were cultured with synthetic miR-29, PEG-SH GNPs and PEG-SH GNPs/miR-29 nanoparticles for 1 week. The density, length and number of neuritis were investigated.Results:The solution of PEG-SH modified GNPs showed a brownish red appearance. The spheres were in uniform distribution under transmission electron microscope. The results of UV absorption spectrum showed a single peak wave. The peak value of UV absorption was near 523 nm. The zeta potential increased gradually with the increased content of PEG-SH. The peak value of zeta potential was 22.5±5.2 mV. With the increase of content of PEG, the particle size of PEG-SH modified GNPs rapidly reached peak value at the early stage and then decreased rapidly to a relatively stable level. The synthetic miR-29 and PEG-SH modified GNPs/miR-29 nanoparticles were implanted into the injury site of spinal cord. At 0-6 h, clear band was observed in the synthetic miR-29 group. However, the band was disappeared rapidly at 12-24 h. In PEG-SH GNPs/miR-29 group, clear band were always observed. The OD values of miR-29 group were 0.34±0.17, 0.78±0.31, 1.28±0.68, 1.64±0.38 at 1, 3, 5 and 7 d after inoculation respectively. There was no significant difference in OD values compared with DMEM group. There was no significant difference in OD values among GNPs, PEG-SH GNPs, PEG-SH GNPs/miR-29 and DMEM group. The density (56.38±3.65 μm 2), length (78.25±3.72 μm) and the number [(356±34.52) /1,000×high power field] of neurites in PEG-SH GNPs/miR-29 group were higher than those in miR-29 group, PEG-SH modified GNPs group and saline group. However, there was no significant difference in the density, length and number of neurite between PEG-SH GNPs/miR-29 and serum group. Conclusion:PEG-SH modified GNPs/miR-29 nanoparticless have good biological properties. It can induce the proliferation and differentiation of neural stem cells with protective effects on miR-29.

OBJECTIVETo investigate the protective effect of LR-90 on articular cartilage in rabbit model of osteoarthritis.

METHODSThe cultured rabbits chondrocytes were assigned to be treated with IL-1β (10ng/ml) or IL-1β (10ng/ml)+LR-90 (50 mg/L). The mRNA expression of MMP-13, ADAMTS-5, aggrecan and collagen II in chondrocytes were assessed by real-time quantitative reverse transcription polymerase chain reaction (RT-PCR). Twenty male New Zealand white rabbits underwent bilateral anterior cruciate ligament transection (ACLT) to establish a animal model of osteoarthritis. Four weeks after model established, on the basis of randomization one knee of each rabbit was treated with 50 mg/L LR-90 in normal saline (NS) (experimental group) and the other knee was treated with same volume of NS (control group), 1/week × 5. Nine weeks after ACLT all rabbits were sacrificed and the knee joints were evaluated by gross morphology and histology. The mRNA expression of IL-1β, MMP-13, ADAMTS-5, aggrecan and collagen Ⅱ in articular cartilage was analyzed by RT-PCR.

RESULTSGross morphology and Mankin histological evaluation showed that the extent and grade of cartilage damage in the experimental group were less severe than those in the control group.Compared to IL-1β group, LR-90 treatment suppressed the mRNA expression of MMP-13 and ADAMTS-5, and enhanced aggrecan and collagen Ⅱ mRNA expression. Consistent with the in vitro results, the intraarticular LR-90 administration suppressed the mRNA expression of IL-1β,MMP-13 and ADAMTS-5 (all P<0.01), while enhanced mRNA expression of aggrecan and collagen Ⅱ in cartilage (all P<0.01).

CONCLUSIONLR-90 protects against cartilage degradation and inhibits the progression of osteoarthritis in rabbit mode1 of osteoarthritis, which is associated with the suppressing IL-1β, MMP-13, ADAMTS-5 and promoting aggrecan and collagen Ⅱ mRNA expression in cartilage.

ADAM Proteins ; metabolism ; Aggrecans ; metabolism ; Animals ; Anterior Cruciate Ligament ; surgery ; Butyrates ; pharmacology ; Cartilage, Articular ; metabolism ; pathology ; Cells, Cultured ; Chondrocytes ; metabolism ; Collagen Type II ; metabolism ; Disease Models, Animal ; Injections, Intra-Articular ; Interleukin-1beta ; pharmacology ; Male ; Matrix Metalloproteinase 13 ; metabolism ; Osteoarthritis ; drug therapy ; Rabbits