Negative pressure promotes epidermal differentiation of bone marrow mesenchymal stem cells / 中国组织工程研究

BACKGROUND: As a physical factor, negative pressure can promote the osteogenic differentiation and endothelial differentiation of mesenchymal stem cells. If a negative pressure exerts effects on the epidermal differentiation of mesenchymal stem cells, it will be highly important for the combination use of negative pressure and mesenchymal stem cells in wound healing. OBJECTIVE: To explore the effect of negative pressure on the epidermal differentiation of bone marrow mesenchymal stem cells. METHODS: Bone marrow mesenchymal stem cells of New Zealand white rabbits were isolated and cultured. Then, the passage 3 cells were induced for epidermal differentiation under negative pressure (-16.625 kPA, twice a day, once for 4 hours) as experimental group. Another cells induced under no negative pressure were used as control group. After induction, cell growth curve was drawn in each group, and the expression of cytokeratin 5 and cytokeratin 10 mRNA was examined by real-time PCR at 2 weeks after induction. RESULTS AND CONCLUSION: The cell growth of the experimental group was inhibited, and the mRNA expression of cytokeratin 5 and cytokeratin 10 was significantly increased compared with the control group (P < 0.05). These findings indicate that under the condition of negative pressures, the epidermal differentiation ability of bone marrow mesenchymal stem cells is increased, and in contrary, the cell proliferation is inhibited.

Antibacterial dental adhesive containing nanoantibacterial inorganic fillers / 华西口腔医学杂志

OBJECTIVE@#This investigation aimed to develop a novel antibacterial dental adhesive containing nanoantibacterial inorganic fillers and measure the dentin bonding strength, mechanical properties, and antibacterial property of the novel adhesive in vitro.@*METHODS@#Novel nanoantibacterial inorganic fillers containing quaternary ammonium salt with long chain alkyl were synthesized on the basis of previous research. These novel nanoantibacterial inorganic fillers were added into the dental adhesive to prepare novel nanoantibacterial dental resin composite at mass fractions of 0%, 2.5%, 5.0%, 7.5%, and 10%; 0% was used as control. Dentin shear bonding test was used to evaluate the bonding strength. Flexural test was utilized to measure the novel resin composite flexural strength and elastic modulus. A dental plaque microcosm biofilm model with human saliva as inoculum was formed. Colony forming unit, lactic acid production, and live/dead assay of the biofilm on novel dental adhesive were calculated to assess the effect of novel dental adhesive on human dental plaque microcosm biofilm.@*RESULTS@#The dentin shear bond strength, flexural strength, and elastic modulus were 28.9 MPa, 86.6 MPa, and 4.2 GPa, respectively, when the nanoantibacterial inorganic filler mass fraction in the dental adhesive reached approximately 5.0%. Consequently, the dentin shear bond strength and mechanical properties significantly increased. Addition of 2.5% nanoantibacterial inorganic fillers into the dental adhesive exerted no adverse effect on the mechanical properties significantly (P>0.05). Dental adhesive containing 5% or more nanoantibacterial inorganic fillers inhibited the metabolic activity of the dental plaque microcosm biofilm significantly, thereby displaying a strong antibacterial potency (P<0.05).@*CONCLUSIONS@#This novel antibacterial dental adhesive, which contained 5.0% nanoantibacterial inorganic filler, exhibited promising bonding strength, mechanical property, and antibacterial ability. Hence, this adhesive can be potentially used in caries inhibition in dental application.

The effects of chitosan oligosaccharides on OPG and RANKL expression in a rat osteoarthritis model

Abstract Purpose: To investigate the effect of chitosan oligosaccharides (COS) against osteoarthritis (OA) and preliminarily discuss the osteoprotegerin (OPG), receptor activator of NF-κB ligand (RANKL) and RANK expression in a rat OA model. Methods: Thirty-six 6-week-old Male SD rats were randomly divided into three groups: sham-operated group(CON), OA-induction group(OA), COS intervention group(n=12/group). At 4 weeks after the operation, COS (50 ul) intervention weekily for consecutive 5 weeks. The OA and CON groups received an injection of 50 ul physiological saline. At death, 11 weeks following surgery, cartilage was harvested and total RNA and protein were extracted. Both the morphological changes of the cartilage were observed and harvested the total RNA and protein. Meanwhile, the expression of OPG, RANKL and RANK in cartilage were determined. Results: The expression of OPG and RANKL were both enhanced in the cartilage of the OA model. Compared with the OA group, COS treatment improved the cartilage damage (both extent and grade). Furthermore, the COS group showed highly OPG and lower RANKL. Simultaneously, COS treatment upregulated the ratio of OPG/RANKL and downregulated the RANKL/RANK. Conclusion: Chitosan oligosaccharides may be used as a unique biological agent to prevent and treat osteoarthritis, and this effect is associated with modulation of the expression of osteoprotegerin and receptor activator of NF-κB ligand.

Single lung transplantation for emphysema: analysis of 6 cases / 南方医科大学学报

<p><b>OBJECTIVE</b>To review the experience with the management of single lung transplantation for emphysema.</p><p><b>METHODS</b>Between January 2003 and August 2006, single lung transplantation was performed in 6 patients for emphysema with cold low potassium solution flushing. A triple-drug regimen was adopted using steroids, mycophenolate mofetil and tacrolimus as the maintenance immunosuppressants. Chest radiograph score, oxygenation index, and pulmonary arterial pressure of the patients in early after the transplantation were reviewed.</p><p><b>RESULTS</b>All the 6 patients survived for over 30 days after the operation, and 4 of them remained alive with good quality-of-life. Four patients recovered from acute rejection successfully after methylprednisolone pulse therapy for 3 days. One patient underwent reoperation for hemorrhage in the thoracic cavity and finally recovered; spontaneous pneumothorax of the autologous lungs occurred in two patients, who underwent reoperation but finally died 74 days and 77 days after the transplantation, respectively.</p><p><b>CONCLUSION</b>Single lung transplantation is effective for end-stage emphysema. Carefully selected recipients and comprehensive design of the surgical procedures are critical to successful lung transplantation.</p>

Injection of activated carbon nanoparticles for guiding lymphadenectomy during minimal invasive surgery in lung cancer / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To evaluate the clinical value of activated carbon nanoparticles for guiding lymphadenectomy in lung cancer.</p><p><b>METHODS</b>Fourty-two lung cancer patients were divided into two groups: the control group (22 cases) and experiment group (20 cases) who received activated carbon nanoparticles injection around the tumor either by endoscopic injection or intraoperative subserosal injection. The number of dissected lymph node, black-stained lymph node, positive lymph node and the side effect of the procedure were analyzed, respectively.</p><p><b>RESULTS</b>No severe complication was observed in the experiment group. The operative time was not prolonged significantly in the experiment group either. However, the number of average lymph nodes dissected in the experiment group (25.5) was significantly more than that in the control group (14.6) (P <0.01).</p><p><b>CONCLUSION</b>Local injection of activated carbon nanoparticles around the tumor during surgical exploration is effective, safe and easy to do for guiding lymphadenectomy in lung cancer patient.</p>

The preliminary study on molecular biologic staging of non-small cell lung cancer lymph nodes / 中国基层医药

Objective To analyze negative lymph nodes of 34 non-small cell lung cancer(NCLC) patients with total correction by means of fluorescent quantitation PCR and immunohistcchemistry,and to form molecular bi- ology staging.Methods Clinical data and tissue samples of 193 lymph nodes were collected from 34 patients under- going resection for non-small cell lung cancer.Using fluorescent quantitation reverse transcription-polymerase chain reaction(RT-PCR) and immunohistochemistry method,lymph nodes were examined for CEA gene mRNA,P53 and CK to form molecular biology staging.All the patients were followed-up for an average of forty months.Results The CEAmRNA was identified in 21.7% (42/193) lymph nodes negative patients from 17 patients(17/34,50%); TMN staging was up-regulated in 8 patients;positive lymph nodes were increased in 9 patients.P53 and AE1/AE3 were identified 9.8%(19/193) from 11 patients,18.6 % (36/193)from 15 patients,separately;TMN staging was up-regulated in 2 patients of P53 examination and 5 patients of AE1/AE3 analysis;positive lymph nodes were in- creased in in 7 patients of P53 examination and 11 patients of AE1/AE3 analysis.There was obvious statistical sig- nificance in them,but the molecular biology staging based on the three markers was not an independent factor on re- currence and metasis of lung cancer.Conclusion CEAmRNA.P53 and AE1/AE3 analysis could find lung cancer micrometasis more sensitively to form molecular biology staging which was relative to the prognosis,but not an inde- pendent prognostic indicator.It might be good to the therapy strategy after operation.