Objective To introduce the development of the collagen materials in drug release and tissue engineering. Methods Literature review and complex analysis were adopted. Results In recent years, some good progress hasbeen made in the studies of collagen, and study on collagen-based materials has become an investigative hotspot especially in tissue engineering. Some new collagen-based drug delivery andengineered materials have come into clinically-demonstrated moment, which willpromote their clinical applications in tissue repairs.ConclusionCollagen has been considered a good potential material in drug release, especially in the tissue-engineering field. To give collagen new characters we should pay more attention to grafting with different function branches through chemistry technique in the future work, except- moderate cross-linking treatment or commingling withother nature or synthesized macromolecules.
Objective To study the medicine dynamics, distribution in tissue and abdominal cavity fluid concentration of 5-FU after giving intraperitoneal by using a gelatin carrier to be made 5-FU slowing-release microballoons. Methods 5-FU slowing-release microballoons medicine release speed, tissue distributing and the concentration in abdominal cavity fluid were measured by high performance liquid chromatography. Results 5-FU wrapped by gelatin were slowly released. The concentration in abdominal cavity fluid was obviously higher than that in tissue or in blood. Using established standard curve line, it was proved that in body area under curve (AUC) of 5-FU slowing-release microballoons group was obviously higher than that of simple 5-FU injection group, analyzed by 3p97 pharmacokinetic software management. Conclusion 5-FU enwrapped by gelatin can retain an effective anticancer activity concentration in abdominal cavity 7 days after giving intraperitoneal and it is distributed mostly in abdominal cavity.
Chitosan is a kind of biological material with good histocompatibility and gradual biodegradability in vivo. It has no toxicity or side-effect. For its gradual degradation, chitosan and adriamycin were mixed and formed drug delivery system (DDS). The release test of DDS and exudant of DDS in inhibiting OS-116 were examined in vitro. The results were as following: the DDS could release adriamycin in slow and stable way. The SO-116 inhidition rate of the exudant of the DDS on the 1st, 20th, 40th and 60th day was 58.11%, 36.48%, 24.32% and 21.62% respectively. It was concluded that the drug delivery system was a slow release system. It could maintain the concentration of adriamycin in a certain level. It was also suggested that the chitosan was a good carrier for slow release of chemotherapeutic drug in local therapy for postoperative treatment of bone tumor.
ObjectiveTo construct bone morphogenetic protein 2 (BMP-2) gelatin/chitosan hydrogel sustained-release system, co-implant with induced pluripotent stem cells (iPS) derived mesenchymal stem cells (MSCs) to hydroxyapatite (HA)/zirconium dioxide (ZrO2) bio porous ceramic foam, co-culture in vitro, and to explore the effect of sustained-release system on osteogenic differentiation of iPS-MSCs.MethodsBMP-2 gelatin/chitosan hydrogel microspheres were prepared by water-in-oil solution. Drug encapsulation efficiency, drug loading, and in vitro sustained release rate of the microspheres were tested. HA/ZrO2 bio porous ceramic foam composite iPS-MSCs and BMP-2 gelatin/chitosan hydrogel sustained release system co-culture system was established as experimental group, and cell scaffold complex without BMP-2 composite gelatin/chitosan hydrogel sustained release system as control group. After 3, 7, 10, and 14 days of co-culture in the two groups, ALP secretion of cells was detected; gene expression levels of core binding factor alpha 1 (Cbfa1), collagen type Ⅰ, and Osterix (OSX) were detected by RT-PCR; the expression of collagen type Ⅰ was observed by immunohistochemical staining at 14 days of culture; and cell creep and adhesion were observed by scanning electron microscopy.ResultsBMP-2 gelatin/chitosan hydrogel sustained-release system had better drug encapsulation efficiency and drug loading, and could prolong the activity time of BMP-2. The secretion of ALP and the relative expression of Cbfa1, collagen type Ⅰ, and OSX genes in the experimental group were significantly higher than those in the control group at different time points in the in vitro co-culture system (P<0.05). Immunohistochemical staining showed that the amount of fluorescence in the experimental group was significantly more than that in the control group, i.e. the expression level of collagen type Ⅰ was higher than that in the control group. The cells could be more evenly distributed on the materials, and the cell morphology was good. Scanning electron microscopy showed that the sustained-release system could adhere to cells well.ConclusioniPS-MSCs have the ability of osteogenic differentiation, which is significantly enhanced by BMP-2 gelatin/chitosan hydrogel sustained-release system. The combination of iPS-MSCs and sustained-release system can adhere to the materials well, and the cell activity is better.
Objective To investigate the promotion effects of the collagen membrane incorporating bFGF impregnated microspheres on the wound healing of the pigskin losing its full-thickness layers. Methods The bFGF containing microspheres was added into the dry microspleres.The collagen membranes were prepared by incorporating bFGF-impregnated microspheres, and 6 York pig models of skin wounds with loss of their full-thickness layers were established for the ob servation of the effects on the wound healing. Results The healing time and the 28day healing rate were 27.30±1.14 days and 98.12%±1.97%, respectively.The healing rate was significantly higher and the healing time was significantl y shorter in the experimental group than in the control group (Plt;0.05). The histological examination showed that the proliferation condition of the epidermiswasalso much better in the experimental group. Conclusion Incorporation of bFGF-impregnated microspheres into the collagen membrane is a promising method of pro moting the healing of the wound with a loss of the fullthickness skin.
【Abstract】ObjectiveTo study the application of ultrasonically activated scalpel in laparoscopic intestinal adhesion release.MethodsIntestinal adhesion release with ultrasonically activated scalpel under laparoscope was performed in 29 patients suffered from intestinal adhesive obstruction after gynecological operation. ResultsAll operations were successfully performed, and none of them converted into open surgery. Intestinal disruption occurred durring operation in 2 patients with extensive intestinal denseadhesion which were mended successfully under laparoscope. The operative duration was 30-150 min (mean 45 min). Postoperative complications such as bowel leakage, bleeding, abdominal infection were not experienced. Postoperative hospital stay was 3-7 days (mean 4 days). No case had relapse symptom such as abdominal distention or pain after 1-24 months of followup. ConclusionCompared with electric scalpel, ultrasonically activated scalpel can improve the operative safety, lessen tissue damage, shorten operative time, and reduce the chance of relapse in laparoscopic operation in gynecology.
Objective To evaluate the safety and efficacy of the operation performed under the video-assisted thoracoscope to release the anterior part of the spine of the patient with severe adolescent idiopathic scoliosis (AIS). Methods From April 2004 to July 2006, 24 patients with AIS (Illness course, 1.5-9 years; Lenke Ⅰ in 17 patients, Lenke Ⅱ in 7; right scoliosis in 22, left scoliosis in 2), among whom there were 9 males and 15 females, with an average age of 14.7 years (range, 11-21 years) at the time of the operation. Before operation, the thoracic vertebral Cobb anger at the coronal plane was averaged 78.3°(range, 65-125°). All the patients had normal muscle strength and muscle tension in their lower limbs, but 5 of the patients had a decrease of the superficial sensation in their lower limbs. All the patients had a moderately or severely decreased lung reserve function. Under general anesthesia, the patient was placed in the lateral position to set up a work channel for thoracoscopy. The releasing of the thoracic intervertebral space and the confluence of the bone grafts were performed. During Stage Ⅰ or Stage Ⅱ, the orthopedic procedures for the posterior part of the scoliosis spine, the internal fixation, and the confluence ofthe bone grafts were completed. ResultsAll the patients survived the periodof perioperation. During operation, there was a hemorrhage of 50-200 ml, averaged 100 ml, with a postoperative thoracic closely-drained fluid of 100-150 ml. The incision was healed by the first intention. Each patient underwent the releaseof 4-6 intervertebral spaces, with an average of 5.5 spaces released. The average coronal Cobb angle was 45.6°(range, 25-75°). The physiological curvatureat the sagittal plane was normal, with an improved shape of the spine. The follow-up for 3-18 months averaged 9.3 months revealed that the bilateral pulmonary markings were clear, with confluence of the orthopedic segment of the spine. The patients could live and work normally, and had a significantly-improved psychological condition and an active social participation because of their improved appearance. Conclusion The releasing of the anterior part of the spine under the video-assisted thoracoscope can effectively release the adolescent idiopathic scoliosis and improve the flexibility of the spine, with a smaller degree of the surgical wound and a faster and clearer exposure of the spinal column during operation.
In order to observe the curative effect and general reaction of locally used adriamycin (ADM)-loaded chitosan drug delivery system on giant cell tumor of bone after curettage. The cavities of 4 cases of giant cell tumor after curettage were filled with ADM-loaded chitosan drug delivery system with 4 times the dosage usually used for intravenous application. After operation, the concentration of ADM in plasma on the 1st, 2nd and 5th day, and the functions of liver and kidney on the 1st week, 1st month and 6th month were all investigated. The results were that the concentration of ADM in plasma was (143.05 +/- 27.55) ng/ml, (52.17 +/- 11.28) ng/ml and (4.25 +/- 3.07) ng/ml respectively, and the functions of liver and kidney were all normal in 6 months. After a follow-up of 7-19 months, no local or general reactions were observed and X-ray showed no recurrence. Therefore, it was concluded that the locally used ADM-loaded chitosan delivery system was safe and effective in treatment of giant cell tumor of bone after curettage.
Objective To evaluate the cost-effectiveness of three LTBI screening strategies: the tuberculin skin test (TST), the T-SPOT.TB and the combination of TST and T-SPOT (TST+T.SPOT), to provide economic evidence for T.SPOT application in China. Methods A decision analysis model evaluated three strategies among a cohort of 1000 tuberculosis (TB) close contacts, using incremental cost-effectiveness of prevention a active TB patient (1 year post contact). Meta analyses were conducted to calculate the key parameters of T.SPOT and TST. The official data or literature was searched and the unaccessible data was to specify other parameters, such as cost, LTBI prevalence, etc. The one-way sensitivity analysis was performed, varying key parameters over a wide range of reasonable values to evaluate the impact of data uncertainties and to determine the robustness of our overall conclusion. Results a) As for the total cost, the TST+T.SPOT strategy (?212 213.81 per 1 000 contacts) cost the least, while the single T.SPOT strategy cost the most; b) Subsequently, the TST+T.SPOT strategy required less contacts to be treated to prevent an active case of TB (8.31) than the single TST strategy (25.67); c) the TST+T.SPOT strategy shared the most cost-effectiveness (?3 063.50 per active TB case prevented) than the single TST or T.SPOT strategy; and d) The results of one-way sensitivity analyses showed that cost-effectiveness values were sensitive to changes in LTBI prevalence (gt;60%), Sen and Spn of TST test (gt;70%), with the single TST being superior to the single T.SPOT. Conclusion The Single T.SPOT strategy enjoys the most cases prevented from active TB, while the TST+S.SPOT strategy is the most cost-effective. The conclusion is sensitive to a few parameters, such as LTBI prevalence, but the TST+T.SPOT strategy is always the best.
ObjectiveTo review and analyze the long-term results of delayed repair of median nerve injury. MethodsBetween January 2004 and December 2008, 228 patients with median nerve injury undergoing delayed repair were followed up for more than 4 years, and the clinical data were retrospectively analyzed. There were 176 males (77.19%) and 52 females (22.81%), aged 2-71 years (median, 29 years). The main injury reason was cutting injury in 159 cases (69.74%);203 cases had open injury (89.04%). According to the injury level, injury located at area I (upper arm) in 38 cases (16.67%), at area II (elbow and proximal forearm) in 53 cases (23.25%), at area III (anterior interosseous nerve) in 13 cases (5.70%), and at area IV (distal forearm to wrist) in 124 cases (54.39%). The delayed operations included delayed suture (50 cases, 21.93%), nerve release (149 cases, 65.35%), and nerve graft (29 cases, 12.72%). ResultsFor patients with injury at area I and area II, the results were good in 23 cases (25.27%), fair in 56 cases (61.54%), and poor in 12 cases (13.18%) according to modified Birch and Raji’s median nerve grading system;there was significant difference in the results between 3 repair methods for injury at area II (χ2=6.228, P=0.044), but no significant difference was found for injury at area I (χ2=2.241, P=0.326). Twelve patients (13.18%) needed musculus flexor functional reconstruction. Recovery of thenar muscle was poor in all patients, but only 5 cases (5.49%) received reconstruction. Thirteen cases of nerve injury at area III had good results, regardless of the repair methods. For patients with injury at area IV, the results were excellent in 6 cases (4.84%), good in 22 cases (17.74%), fair in 72 cases (58.06%), and poor in 24 cases (19.35%) according to Birch and Raji’s grading system;there was significant difference in the results between 3 repair methods (χ2=12.646, P=0.002), and the result of delayed repair was better. ConclusionThe results of delayed repair is poor for all median nerve injuries, especially for high level injury. The technique of repair methods vary with injury level. For some delayed median nerve injuries, early nerve transfer may be a better choice for indicative patients.