Objective To introduce the evidence-based evaluation on off-label uses at home and abroad, so as to investigate a systematic method of evidence-based evaluation on off-label uses. Methods In combination with the domestic and international research literature, a systematic method of evidence-based evaluation on off-label uses was discussed from the following three aspects: sources of evidence, levels of evidence, and recommendation strength. Results Sources of evidence included Clinical Pharmacology, DRUGDEX? System, NCCN Drugs amp; Biologics Compendium and handsearched literature. Levels of evidence and recommendation strength could refer to the 2009 grade system of Oxford Centre for Evidence-Based Medicine, and the strength of recommendations and scientific support of DRUGDEX? System. Conclusion A systematic method of evidence-based evaluation on off-label uses is initially established.
Objective To find a kind of simple and effective method for purifying and label ing stromal vascular fraction cells (SVFs) so as to provide a theoretical basis for cl inical application of SVFs. Methods The subcutaneous adi pose tissue were harvested form volunteers. The adi pose tissue was digested with 0.065%, 0.125%, and 0.185% type I collagenase,respectively. SVFs were harvested after digestion and counted. After trypan blue staining, the rate of viable cells was observed. SVFs was labeled by 1, 1’-dioctadecyl-3, 3, 3’, 3’-2-tetramethy-lindocyanine perchlorate (DiI). The fluorescent label ing and growth was observed under an inverted fluorescence microscope. MTT assay was used to detect cell proliferation. Results The number of SVFs was (138.68 ± 11.64) × 104, (183.80 ± 10.16) × 104, and (293.07 ± 8.31) × 104 in 0.065% group, 0.125% group, and 0.185% group, respectively, showing significant differences among 3 groups (P lt; 0.01). The rates of viable cells were 91% ± 2%, 90% ± 2%, and 81% ± 2% in 0.065% group, 0.125% group, and 0.185% group, respectively, and it was significantly higher in 0.065% group and 0.125% group than in 0.185% group (P lt; 0.01), but no significant difference was found between 0.065% group and 0.125% group (P=0.881). Inverted fluorescence microscope showed that the cell membranes could be labeled by DiI with intact cell membrane, abundant cytoplasm, and good shape, but nucleus could not labeled. SVFs labeled by DiI could be cultured successfully and maintained a normal form. MTT assay showed that similar curves of the cell growth were observed before and after DiI labeled to SVFs. Conclusion The optimal collagenase concentration for purifying SVFs is 0.125%. DiI is a kind of ideal fluorescent dye for SVFs.
Objective To study the biological characteristic of rabbit bone marrow mesenchymal stem cells (BMSCs) double-labeled by PKH26 and BrdU in vitro, and to construct tissue engineered cardiac patch in vitro. Methods The BMSCs were harvested from 6-month-old New Zealand rabbits and labeled with PKH26 and BrdU. The growth and fluorescent intensitywere observed by inverted phase contrast microscope, fluorescent microscope, flow cytometry, and MTT detection. Thecharacteristics of double-labeled BMSCs differentiating into osteoblasts and adipocytes, respectively, in vitro were identified by alkal ine phosphatase (ALP) staining, Al izarin red staining, Oil red O staining, immunocytochemical technique of collagen type I, and osteocalcin expression. The labeled BMSCs were seeded on the small intestinal submucosa (SIS) and co-cultured for 5-7 days to construct tissue engineered cardiac patch. The patches were tested by inverted phase contrast microscope, fluorescent microscope, scanning electron microscope, and HE staining to observe the cell prol iferation. Results The double-labeled cells grew well and showed red fluorescence. There was no significant difference in the growth characteristic between the labeled and unlabeled cells. There was no significant difference in the expression of stem cell specific surface antigen between before lebel ing and after lebel ing. After osteogenic induction of labeled BMSCs, ALP staining and Al izarin red staining were positive, and the cells expressed collagen type I and osteocalcin. After adipocytes induction, l ipid droplets could be observed in cytoplasm by Oil red O staining. After the co-culture in vitro for 5-7 days, the double-labeled cells grew well, showing a multi-layer cellular structure on the surface of SIS. Conclusion Rabbit BMSCs can be double-labeled with PKH26 and BrdU stably. The labeled cells still have the potential of self-renewal abil ity and multipotent differentiation abil ity; tissue engineered cardiac patch can be constructed by co-culturing labeled BMSCs and SIS in vitro.
Objective The combined appl ication of green fluorescent protein (GFP) and confocal laser scanning microscope three-dimensional reconstruction (CLSM-3DR) were used to monitor the construction and in vivo transplantation of tissue engineered bone (TEB), to provide for technology in selection of scaffolds and three-dimensional constructional methods. Methods After bone marrow mesenchymal stem cells (BMSCs) were isolated from a 2-year-old green goat by a combination method of density gradient centrifugation and adherent culture, and the expressions of CD29, CD60L, CD45, and CD44 in BMSCs were detected by flow cytometry. Plasmid of pLEGFP-N1 was ampl ified, digested by enzymes (Hind III, BamH I, Sal I, and Bgl II), and identified. Transfection of pLEGFP-N1 into PT67 cells was performed under the help of l iposome. Positive PT67 cells were picked out with G418, and prol iferated for harvesting virus. Based on the titre of virus, after BMSCs were infected by virus containing pLEGFP-N1, GFP positive BMSCs were collected and prol iferated for seeding cells. TEB was fabricated by GFP positive BMSCs and decalcified bone matrix (DBM) and observed by CLSM-3DR for the evaluation of the distribution and prol iferation of seeding cells. After TEB was transplanted in the defect of goat femur, CLSM was used for observing the survival and distribution of GFP positive cells in the grafts. Results The isolated cells were fibroblast-l ike morphous, with the positive expression of CD29 and CD44, and negative expression of CD60L and CD45. The digested production of pLEGFP-N1 was collected for ionophoresis, whose results showed the correct fragment length (6 900 bp). The virus of pLEGFP-N1 was harvested by transfection of pLEGFP-N1 into PT67 cells and used for further infection to obtain GFP positive BMSCs. The prol iferated GFP positive BMSCs and DBM were used for fabrication of TEB. The distribution, prol iferation, and migration of BMSCs in TEB were observed by CLSM-3DR. GFP positive cells also were observed in images of TEB graft in goat femur 28 days after transplantation. Conclusion The BMSCs labeled by GFP in three-dimensional scaffold in vivo were monitored well by CLSM-3DR. It suggests a wide use potency in monitoring of three-dimensional cultured TEB.
Objective To further investigate the possible mechanism of the correction of scol iosis with Staple by quantifying the effect of Staple on growth rate of vertebral growth plates in goat scol iosis. Methods Experimental scol iosis was created in 10 juvenile female goats by using unilateral pedicle screws asymmetric tethering. After 8-10 weeks, goats were divided randomly into Staple treated group (n=5) and control group (n=5). All tethers were removed in both groups and Staplegroup underwent anterior vertebral stapl ing with 4-5 shape memory alloy Staples along the convexity of the maximal curvature after posterior tether being removed. All goats were observed for an additional 8-13 weeks, the Cobb angle were measured to observe the correction of scol iosis. The fluorochromes Oxytetracycl ine and Calcein were administered respectively 18 and 3 days before death to label the ossifying front under the growth plates. Superior intervertebral disc of apical vertebra and two adjacent growth plates were completely harvested in all goats. All specimens were embedded with polymethyl methacrylate and sl iced undecalcified. The growth rates of the vertebral growth plates were calculated by measuring the distance between the two fluorescent l ines with fluorescence microscope. Results Nine (5 in Staple treated group and 4 in control group) of 10 tethered goats had progressive scol iotic curves of significant magnitude after 8-10 weeks of tethering. In Staple treated group, the Cobb angles were (34.8 ± 12.4)° at the instant after treatment , and (15.6 ± 11.7)° 8-13 weeks after treatment; showing statistically significant difference (P lt; 0.05). In the control group, the Cobb angles were (49.3 ± 18.0)° at the instant after treatment, and(49.0 ± 17.6)° 8-13 weeks after treatment; showing no statistically significant difference (P gt; 0.05). In Staple treated group, the growth rate of growth plate in the concavity (3.27 ± 0.96) μm/d was higher than that in convexity (1.84 ± 0.52) μm/d (P lt; 0.05), while the growth rate of the concavity did not differ significantly from that of the convexity in control group (P gt; 0.05). Conclusion Staple can significantly alter the growth rates of two sides of vertebrae in scol iosis with the growth rate of concavity exceeding the one of convexity, which results in correction of deformity.
【Abstract】 Objective To explore the optimal dosage, timing and cytotoxicity of bromodeoxyuridine (BrdU) labelling for rabbit adipose-derived stromal stem cells (ADSCs) in vitro so as to confirm its feasibil ity for stem cells labell ing and tracer means. Methods Six rabbits were used in this experiment, aged 8-12 weeks, weighing 1.5-2.0 kg and neglecting their gender. 1-2 mL fat was removed, the ADSCs were isolated and cultured using the adherence method in vitro . The 3rd passage of ADSCs was incubated with BrdU at 5, 10, 15 and 20 μg/mL (groups A, B, C and D）for 12, 24, 48 and 72 hours to identify the optimal BrdU concentration and incubating time for cell labell ing. Immunohistochemistry and trypanblau strain were performed respectively to calculate the labell ing index (positive rate) and the cells’ activity for different time after BrdU labell ing. The ADSCs without BrdU labell ing were used as control (Group E）. Results The main appearance of primary ADSCs was short fusiform shape, and of the 3rd passage ADSCs long fusiform shape. The 3rd passage of ADSCs could differentiate into osteoblastsand adipocytes under corresponding inductive medium. The ADSCs’ nucleus show green fluor under fluorescence microscope after labeled by the BrdU. The labell ing ratio increased in groups A, B, C and D after incubating 12 hours, the mean labell ing ratio were 30.6％ ±2.3％，32.4％ ±1.9％，45.8％ ±1.8％，50.8％ ±3.1％ , respectively, and the labell ing ratio of Group E was 0. There were significant differences between groups C, D and Group A (P lt; 0.01). The labell ing ratio of groups A, B, C and D were 45.9％ ±2.0％，87.9％ ±3.3％，90.6％ ±2.9％，91.7％ ±3.2％，respectively after 24 hours and the labell ing ratio of Group E was 0. There were significant differences between groups B, C, D and Group A (P lt; 0.01). The results of all groups after incubating48 hours and 72 h ours were similar to that after incubating 24 hours. The cell counting of groups A, B, C and D were better than that of Group E, but showing no siginificant differences（P gt; 0.05）. Conclusion The most appropriate time for BrdU labell ing ADSCs is 48 hours, the most appropriate concentration is 10 μg/mL. The labell ing rate is high and cytotoxicity is l ittle.
Objective To explorer the survival time of autogeneic BMSCs labeled by superparamagnetic iron oxide (SPIO) in rabbit intervertebral discs and the rule of migration so as to prove bases of gene therapy preventing intervertebral disc degeneration. Methods Twelve rabbits were used in this experiment, aged 8-10 weeks, weighing 1.5-2.0 kg and neglecting their gender. BMSCs were separated from rabbits bone marrow by density gradient centrifugation and cultivated, and the 3rd generation of BMSCs were harvested and labeled with SPIO, which was mixed with poly-l-lysine. The label ing efficiency was evaluated by Prussian blue staining and transmission electron microscope. Trypanblau stain and MTT were performed to calculate the cell’ s activity. Rabbits were randomly divided into experimental group (n=8) and control group (n=4), the labeled BMSCs and non-labeled BMSCs (5 × 105/mL) were injected into their own intervertebral discs (L1,2, L2,3, L3,4 and L4,5), respectively. At 2, 4, 6 and 8 weeks, the discs were treated with Perl’s fluid to observe cell survival and distribution. Results The label ing efficiency of BMSCs with SPIO was 95.65% ± 1.06%, the cell activity was 98.28% ± 0.85%. There was no statistically significant difference in cell prol iferation within 7 days between non-labeled and labeled cells (P gt; 0.05). After 8 weeks of operation, the injected cells was al ive. ConclusionLabeled BMSCs with SPIO is feasible in vitro and in vivo, and the cells can survive more than 8 weeks in rabbit discs.
Objective To observe whether theograde axial flow of retinal ganglion cells (RGC) in diabetic rats at the early stage was damaged. Methods Diabetic model was induced by streptozotocin in 6 adult male Sprague-Dawley (SD)rats. Fluorogold (FG) was injected to the superior colliculi 4 weeks later.Streched preparation of retina was made 12 and 72 hours after the injection, and was stained after photographed by fluorescent microscope. The proportion of RGC with different sizes labeled by FG was calculated. Other 6 normal adult male SD rats were in the control group. Results Twelve hours after injection with FG, there was no difference of the total number of RGC in experimental and control group, but the ratio of small RGC was lower in experimental group than that in the control group; 72 hours after injection with FG, The number of RGC, especially the small RGC, decreased obviously in experimental group compared with the control group. Conclusion The speed of the retrograde axial flow of RGC in diabetic rats at the early stage is affected, and the small RGC are damageable. (Chin J Ocul Fundus Dis, 2006, 22: 4-6)
Objective lt;brgt;To investigate the feasibility of labeling iris pigment epithelial（IPE）cells of rabbits with 5（and 6）carboxyfluorescein diacetate succinimidyl ester（CFSE）. lt;brgt; lt;brgt;Methods lt;brgt;Enzyme-assisted microdissection was used to isolate the cultured rabbitprime;s IPE cells.The third or forth subcultured IPE cells were incubated with 2.5，5，10，20，and 40 mu;mol/L of CFSE for 1，5，and10min respectively.The fluorescence intensity was detected by flow cytometry，and the leakage of CFSE and its dyeing were observed by fluorescence antibody labeling. lt;brgt;Results lt;brgt;Incubation with 20 mu;mol/L CFSE under 37℃for1minute was the most optimal condition for IPE cells labeling.The coloration of IPE cells stained by CFSE lasted 4 weeks.There was no leakage of dye from labeled rabbit IPE cells to non-labeled human IPE cells in mixed culture process. lt;brgt; lt;brgt;Conclusion lt;brgt;With the advantages of high rate of dyeing，long time of tracing，safety and convenience，CFSE can be used as a new method to label the rabbitprime;s IPE cells. lt;brgt; lt;brgt;(Chin J Ocul Fundus Dis, 2006, 22: 261-264)
Objective To determine the extent of off-label drug use in Pediatric Wards of West China Second University Hospital in 2010 and analyze its risk factors, so as to provide baseline data for getting acquainted with the extent of off-label drug use in pediatrics in China, and for making policies of off-label drug use. Methods The proportionate stratified random sampling was conducted to select medical advice and discharge medication for hospitalized children in Pediatric Wards in 2010. According to drug instructions, the off-label drug use of prescriptions of all selected children was analyzed in the following aspects, the category of off-label drug use, age, category of drugs and wards. In addition, a logistic regression was done that modeled the odds of receiving an off-label prescription as a function of the following possible risk factors: age, sex and the rank of doctors. Results The total 749 children were selected, and 14 374 prescriptions involving 385 drugs were analyzed. The rate of off-label drug use was 98.00%, 78.96% and 88.05% in children, prescriptions and drug categories, respectively. The main categories of off-label drug use were no pediatric information (29.41%), indication (18.35%), dosage (17.61%) and dosage range (±20%) (13.52%). The top 2 age groups of off-label drug use were adolescents (83.56%) and children (80.58%). The top 4 drugs of off-label use were those for alimentary tract and metabolism (82.28%), anti-infectives for systemic use (75.06%), blood and blood forming organs (79.27%) and respiratory (58.27%). The top 2 wards of off-label drug use were Pediatric Hematology (88.27%) and Neonates (79.12%). In hospital, children, adolescents and male patients had higher risk factors of off-label drug use, and doctors with senior rank prescribed more off-label prescriptions than those with intermediate rank. Conclusion The off-label drug use in Pediatric Wards is common in West China Second University Hospital. On the one hand, drug instructions lack the pediatric information, and, on the other hand, it’s badly in need of developing relevant legislations, regulations or guidelines to regulate off-label drug use, in order to avoid doctor’s professional risks and ensure the safety of pediatric drug use.