Comparison of segmentectomy versus lobectomy for ≤2 cm lung adenocarcinoma with micropapillary and solid subtype negative by intraoperative frozen sections: A multi-center randomized controlled trial / 中国胸心血管外科临床杂志

@#Objective    To compare the clinical effects of segmentectomy and lobectomy for ≤2 cm lung adenocarcinoma with micropapillary and solid subtype negative by intraoperative frozen sections. Methods    The patients with adenocarcinoma who received segmentectomy or lobectomy in multicenter from June 2020 to March 2021 were included. They were divided into two groups according to a random number table, including a segmentectomy group (n=119, 44 males and 75 females with an average age of 56.6±8.9 years) and a lobectomy group (n=115, 43 males and 72 females with an average of 56.2±9.5 years). The clinical data of the patients were analyzed. Results    There was no significant difference in the baseline data between the two groups (P>0.05). No perioperative death was found. There was no statistical difference in the operation time (111.2±30.0 min vs. 107.3±34.3 min), blood loss (54.2±83.5 mL vs. 40.0±16.4 mL), drainage duration (2.8±0.6 d vs. 2.6±0.6 d), hospital stay time (3.9±2.3 d vs. 3.7±1.1 d) or pathology staging (P>0.05) between the two groups. The postoperative pulmonary function analysis revealed that the mean decreased values of forced vital capacity and forced expiratory volume in one second percent predicted in the segmentectomy group were significantly better than those in the lobectomy group (0.2±0.3 L vs. 0.4±0.3 L, P=0.005; 0.3%±8.1% vs. 2.9%±7.4%, P=0.041). Conclusion    Segmentectomy is effective in protecting lungs function, which is expected to improve life quality of patients.

Shanghai Pulmonary Hospital Experts Consensus on the Management of Ground-Glass Nodules Suspected as Lung Adenocarcinoma (Version 1) / 中国肺癌杂志

Background and objective As computed tomography (CT) screening for lung cancer becomes more common in China, so too does detection of pulmonary ground-glass nodules (GGNs). Although anumber of national or international guidelines about pulmonary GGNs have been published,most of these guidelines are produced by respiratory, oncology or radiology physicians, who might not fully understand the progress of modern minimal invasive thoracic surgery, and these current guidelines may overlook or underestimate the value of thoracic surgery in the management of pulmonary GGNs. In addition, the management for pre-invasive adenocarcinoma is still controversial. Based onthe available literature and experience from Shanghai Pulmonary Hospital, we composed this consensus about diagnosis and treatment of pulmonary GGNs. For lesions which are considered as adenocarcinoma in situ, chest thin layer CT scan follow-up is recommended and resection can only be adopt in some specific cases and excision should not exceed single segment resection. For lesions which are considered as minimal invasive adenocarcinoma, limited pulmonary resection or lobectomy is recommended. For lesions which are considered as early stage invasive adenocarcinoma, pulmonary resection is recommend and optimal surgical methods depend on whether ground glass component exist, location, volume and number of the lesions and physical status of patients. Principle of management of multiple pulmonary nodules is that primary lesions should be handled with priority, with secondary lesions taking into account.
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Surgical management of mediastinal hemangioma: a report of 18 cases / 中华胸心血管外科杂志

Objective To summarize our experience in surgical intervention of patients with mediastinal hemangioma.Methods From January 1994 to August 2017,18 patients underwent surgical treatment were diagnosed with mediastinal hemangioma in our department.There were 9 females and 9 males,with the average age of(50.9 ± 14.0) years.Seven patients were seen with signs and symptoms related to the tumor,and the other 11 patients had no symptom.Three cases were located in the anterior mediastinum,1 case in the middle mediastinum and 14 cases in the posterior mediastinum.All of the cases experienced chest computed tomography(unenhanced or contrast-enhanced CT scan).Most mediastinal hemangiomas manifested as well-marginated masses at CT.Seven hemangiomas showed heterogeneous enhancement at contrast-enhanced CT.Calcifications were demonstrated in 2 patients.Preoperative diagnosis was not confirmed in all patients.Two cases were suspected to be hemangioma preoperatively,other cases were suspected to be thymoma,neurofibroma or malignancy.Eight cases were treated by video-assisted thoracic surgery approach,3 of those converted to thoracotomy due to high risk of hemorrhage.Ten cases experienced traditional thoracotomy.Results Seventeen patients had total excision,but one experienced biopsy because of hemorrhage.There were no operative death and major complications.The average operation time was(105.0 ± 49.6) minutes,and the average blood loss was(111.7 ± 138.9) ml.The postoperative hospital stay was (4.7 ± 3.5) days on average.Follow-up time ranged from 1 to 18 months(median,9.6 months).No recurrence was found in the patients with total excision at the time of follow-up.The patient undergoing biopsy showed no progression of the disease for 12 months.Conclusion Mediastinal hemangiomas were rare tumors,without relatively specific clinical manifestation.Calcification and phleboliths on CT scan were helpful in suggesting the vascular nature of the mass.Preoperative diagnosis of mediastinal hemangioma was usually very difficult.Mediastinal hemangiomas were mainly treated by surgical approach and had good prognosis.

Preventive effect of Mongolian medicine Tonglaga-5 Pill on osteoporosis induced by retinoic acid in rats and its mechanism / 吉林大学学报(医学版)

Objective To observe the effect of Mongolian medicine Tonglaga-5 Pill on the osteoporosis induced by retinoic acid in the rats,and to provide experminted basis for its clinical application.Methods 60 female Wistar rats were randomly divided into blank group,model group,Ossptide Tablets group,Tonglaga-5 Pill groups with low,medium and high doses (n=10).The osteoporosis models were induced by retinoic acid in the rats.The levels of serum calcium (Ca), phosphorus (P), alkaline phosphatase (ALP), transforming growth factorβ1 (TGF-β1),insulin like growth factor (IGF-1)and bone indexes were detected and the contents of Ca and P in ash were also detected,and the changes of bone histomorphometry of the rats were observed under light microscope by HE staining.Results Compared with model group,the serum calcium and P contents of the rats in Tonglaga-5 Pill groups were increased,but there were no significant differences (P>0.05);the ALP levels were decreased significantly (P0.05);the contents of calcium and P in ash were increased in different degrees,but there were no significant differences (P>0.05).Compared with control group,the femur maximum width index and minmum width index of the rats in model group were significantly decreased (P0.05).Under light microscope,the rich and full bone trabecula was found in the rat femur in control group;the bone trabecula in model group was decreased,and the bone trabecula in Tonglaga-5 Pill groups was increased. Compared with model group, the trabecular bone areas in Tonglage-5 pill groups and Ossotide group were increased (P<0.05).Conclusion Tonglaga-5 Pill displays a certain preventive effect on the rats with retinoic acid-induced osteoporosis,which can blocks the bone mineral loss,bone tissue structure changes and bone quality decreasing effectively.

Inhibitory effect of adenovirus-mediated endostatin gene transfer on transplanted lung carcinoma in mice / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the effect of adenovirus-mediated endostatin gene transfer on transplanted lung cancer in mice and its mechanism of action.</p><p><b>METHODS</b>Transplant tumor model was induced by subcutaneous inoculation of 2 x 10(6) Lewis lung cancer (LLC) cells into the back of C57BL/6 mice. The mice were treated by intratumoral injection of 2 x 10(9) pfu Ad-mEndostatin. The expression of endostatin in situ and its maintaining time were detected by immunohistochemistry and Western Blot, respectively. The endostatin level in serum was determined by ELISA . The inhibition of tumor growth and changes of survival were recorded and the microvessel density (MVD) was determined by histochemical stainingwith CD31 and CD105 antibodies. The tumor apoptosis was observed by electron microscopy.</p><p><b>RESULTS</b>In comparison with controls, intratumoral injection of Ad-mEndostatin significantly inhibited the tumor growth and metastasis, and prolonged the survival rate of mice (P < 0.05). Strong positive expression of mEndostatin was seen in the tumor tissue after injection of Ad-mEndostatin, immunhistochemically ostained by mouse endostatin monoclonal antibody, while the control groups showed only very low expression or absence. Serum endostatin concentration was 1540 +/- 560 ng/ml at the second week of administration, the expression of endostatin diminished a month later. The microvessel density (MVD)) decreased from 42.4 +/- 4.8 to 10.5 +/- 3.2 per x 200 magnificetion microscopic field by CD10 staining and from 68.5 +/- 4.5 to 37.5 +/- 4.6 by CD31 staining, respectively (P < 0.05). More apoptotic tumor cells were seen under the transmission electron microscope.</p><p><b>CONCLUSION</b>Endostatin gene therapy mediated by adenoviral vector efficiently induces expression of endostatin in vivo, and inhibits the growth and metastasis of tumor. It is concluded that its action is targeted to tumor neovasculature and the mechanism is inhibition of tumor angiogenesis.</p>

Correlates of and willingness to participate in HIV voluntary counseling and testing among migrants in a city of Shanxi province / 中华流行病学杂志

<p><b>OBJECTIVE</b>To determine the correlates of and willingness to participate(WTP) in HIV voluntary counseling and testing (VCT) among migrants in Shanxi province.</p><p><b>METHODS</b>Through quota sampling, a total of 1280 migrants were recruited from 6 different venues where migrants were most likely employed to administer a face-to-face anonymous interview.</p><p><b>RESULTS</b>Knowledge of VCT among migrants was low. Only 56.6% of migrants had heard of HIV voluntary counseling and testing. 64.5% reported willingness to accept VCT after participants were informed that HIV counseling and testing was offered free of charge Centers for Disease Prevention and Control (48.7%), hospital (27.0%) and home (18.5%) were most preferred places for VCT service. Logistic regression analysis indicated that the willingness was associated with having a history of HIV test, having better knowledge of HIV, no discrimination against people with HIV, and high HIV/AIDS perception.</p><p><b>CONCLUSION</b>Community-based health education programs for improving HIV/AIDS knowledge, promoting acceptance of VCT and eliminating discrimination to HIV-infected persons were called for.</p>

In vivo biodegradability of the composite materials for tracheal prosthesis in rats: Collagen/hydroxyapatite and poly(lactic-co-glycolic acid) / 中国组织工程研究

BACKGROUND: Preparing the tracheal prosthesis by biomaterials is crucial for studying the implant of long tracheal defect.The biocompatibility and biodegradability of collagen/hydroxyapatite (Col/HAp) and poly(lactic-co-glycolic acid) (PLGA) in vivo, as a artificial material for tracheal prosthesis, need to be observed.OBJECTIVE: To explore in vivo biodegradability of Col/HAp and PLGA of tracheal prosthesis in rats.DESIGN: Randomized controlling observation.SETTING: Department of Thoracic and Cardiovascular Surgery, Clinical College of Yangzhou University; Department of Thoracic and Cardiovascular Surgery, Changzheng Hospital of the Second Military Medical University of Chinese PLA.MATERIALS: The experiment was carried out in the National Experimental Animal Center of the Second Military Medical University of Chinese PLA from March 2003 to December 2004. Sixteen SD rats of either gender were offered by this center, aged three months and weighed 150-170 g. Col/HAp and PLGA (the copolymer of polylactic acid and polyglycolic acid according to the percent of 90:10) were self-made.METHODS: ①Empirical process: Rats were fed adaptively for 1 week and anesthetized. Then undermining dissection was performed along with musculi dorsal surface toward spine bilaterally, so as to form two capsular gaps, which were implanted with Col/HAp sponge and PLGA fiber mesh cloth respectively, in a size of 10 mm ×10 mm. ②Empirical evaluation: The postoperative activity, incision healing and rejection of rats were observed; 2, 4, 6, 8 weeks postoperatively, the Col/HAp sponge and PLGA mat that were embedded subcutaneously as well as surrounding tissues were determined using scanning electron microscope or transmission electron microscope.MAIN OUTCOME MEASURES: In vivo biodegradability of two materials implanted in rats at different time points.RESULTS: ①All the animals could carry out normal activity, respiration and diet; no incision infection, fluidity, necrosis or sinus tract appeared; there was no edema in the skins of implanted area, neither hypersensitiveness nor toxicity was found; the implant materials had no rejection. ②The features of the implanted materials varied throughout the implantation. During the follow-up, the infiltration of inflammatory cells was found in the interface between the implants and neighboring host tissues in the early stage, phagocytes and fibroblastic cells were also observed later. As the process went on, the materials were biodegraded gradually, encapsulated by phagocytes, and replaced by newly generated fibrous tissues. No remarkable harmful influences of the composite materials on the neighboring host tissues such as apomorphosis, necrosis, hyperplasia and foreign body reaction were observed grossly and microscopically.CONCLUSION: All the implants show a good biocompatibility and biodegradability. Both Col/HAp and PLGA go through a gradual process of biodegradability, biological absorption and replacement by host tissues ultimately in vivo, which suggest that these two kinds of composite biomaterials will be used safely in developing tracheal prosthesis.

Preparation and biological evaluation of Chitin short fiber reinforced polycaprolactone composite / 生物医学工程学杂志

Chitin short fiber reinforced polycaprolactone composite was prepared by melting blending method. The cytotoxicity and biocompatibility of pure polycaprolactone and of chitin short fiber reinforced polycaprolactone composite were investigated in order to provide useful scientific basis for clinical application. The biocompatibility of pure polycaprolactone and that of chitin short fiber reinforced polycaprolactone composite were evaluated by a series of tests, including cytotoxicity test in vitro, acute systemic toxicity test, hemolysis test, pyrogen test and sensitivity test. The results showed that the cytotoxicity scores of the two materials were grade 0 and the growth and proliferation of the cultured cells were not significantly inhibited by the two materials. There were no potential allergic materials in the composites and the maceration extract showed no hemolytic reaction, no acute systemic toxicity and no pyrogen reaction. We conclude that the composites have fine biocompatibility and are safe for clinical use in the reconstruction treatment for chest wall defect.

Experimental study of degradable chitin long fiber reinforced polycaprolactone for reconstruction of chest wall defects / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the application of a novel degradable biomaterial as a chest wall prosthesis and provide valuable scientific basis for clinical application.</p><p><b>METHODS</b>Preparation of chitin long fiber reinforced polycaprolactone (PCL) by means of melt blending and modeling. Full-thickness chest wall defects of 10 cm x 8 cm was created in 10 dogs and then repaired with long chitin fiber reinforced PCL artificial rib in 8 dogs (tested group) and Marlex mesh in 2 dogs (control group). It was dynamically observed that the situation of the implanted chest wall prosthesis and the progress of the regeneration of the chest wall tissue postoperatively.</p><p><b>RESULTS</b>No operative and perioperative deaths were observed in all experimental dogs. In tested group, slight paradoxical respiration occurred in 2 dogs and could not be seen in 2 weeks. No chest wall subsidence and infection occurred. New bone tissue obviously regenerated around both resection ends of the ribs and integrated tightly with artificial ribs. In control group, there were evidently paradoxical respiration and chest wall subsidence. Marlex mesh folded and was enveloped by fibrous tissue.</p><p><b>CONCLUSION</b>Degradable chitin long fiber reinforced PCL can provide effective support to chest walls and is a practicable material for chest wall reconstruction.</p>

The Searches in Reform of Thoracic and Cardiovascular Surgery Teaching Method / 中华医学教育探索杂志

Thoracic and cardiovascular surgery teaching is the focal and difficult point in the whole surgery teaching.This article introduces the authors'reform by using advanced multimedia and image equipment to enhance teaching effect in both theory and practice,using the modern modes such as logic guide,case study and inter-communication to inspire students'passion and by emphasizing basic skill and asepsis environment to build normative teaching in thoracic and cardiovascular surgery.

Experimental study on the reconstruction of circumferential tracheal defects with novel prosthesis / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the feasibility of using new tracheal prosthesis made of biomaterials to replace extensive circumferential tracheal defects in mongrel dogs.</p><p><b>METHODS</b>Three types of tracheal prostheses were developed, whose basic skeleton of tubular mesh was knitted with polypropylene monofilament and poly (lactic-co-glycolic acid) fiber. The inner side of type-I tubular mesh was first coated with polyurethane solution and then with collagen. The exterior of type-I was then immobilized with collagen-hydroxyapatite composites. In contrast, the internal and external walls of type-II were coated with polyurethane solution, which produced a prosthesis similar to a nonporous one, while type-III was coated only with collagen solution. Surgical resection and replacement of a segment of the cervical trachea was performed in 16 adult mongrel dogs. The efficacy of the implanted prosthesis periodically evaluated postoperatively.</p><p><b>RESULTS</b>In group A, only one died from prosthetic dehiscence, another from anastomotic leakage, and the others had uneventful postoperative courses. The implanted prosthesis was completely incorporated with the recipient trachea, where different length of reepithelialization occurred on the luminal surface of the reconstructed trachea. Macroscopic examination showed scattered and different sizes of neo-ossification surrounding the implanted prosthesis. The prosthesis was roentgenopaque when exposed to routine X rays. In contrast, a relatively high number of complications occurred postoperatively in group B and C.</p><p><b>CONCLUSION</b>Type-I tracheal prosthesis may be used effectively for long-segment circumferential tracheal replacement, and appears very promising for clinical application, with further improvements in promoting the epithelialization.</p>

Experimental study in vitro on toxicology and cytocompatibility of collagen/hydroxylapatite (CHA) composite material as part of tracheal prosthesis / 生物医学工程学杂志

Cytotoxicity and cytocompatibility remains the principal theme for biomaterials application in medicine. The purpose of this study was to investigate the cytotoxicity and cytocompatibility of collagen/hydroxyapatite(CHA) composite material in vitro in order to provide useful scientific basis for clinical use. Cellular cultivation in vitro and MTT assay were conducted for evaluating the composite material's influence on the morphology, growth and proliferation of cultured cell(L-929 cell). The hemolysis test was also performed for evaluating the impact on the function and metabolism of erythrocyte. These results demonstrated that the CHA composite material had no cytotoxicity and no hemolytic effect, and it might not be harmful to the morphology of the L-929 cell. The growth and proliferation of the L-929 cell could not be inhibited significantly. The cytotoxicity score of the composite material was grade 0. The hemolysis rate was 1.85%. In conclusion, collagen/hydroxyapatite (CHA) composite material might have good cytocompatibility and be safe for clinical use.

Experimental study on a novel esophageal prosthesis made of composite biomaterials / 中华外科杂志

<p><b>OBJECTIVE</b>To design and develop a novel esophageal prosthesis by selecting appropriate biomaterials, developing special manufacturing techniques, and investigating the feasibility of replacement of cervical esophagus in mongrel dogs.</p><p><b>METHODS</b>In accordance with the requirements of ideal esophageal substitutes, we designed a new type of esophageal prostheses. The inner stent were made with polyurethane of medical grade, and the outer surface of the prosthesis was coated with collagen-chitosan sponge. The silicone tube was used as a control. Thirteen adult mongrel dogs that were divided into two groups were used to establish the experimental models.</p><p><b>RESULTS</b>In the experimental group (n = 8), the esophageal prostheses were completely incorporated with the native esophagus and adherent to the surrounding host connective tissues. Epithelial linings of varying degrees were formed on the luminal surface, and complete epithelization was seen in 1 month postoperatively. The granulation at the sites of the anastomosis in this group was less significant than that of the control group. One dog has been surviving for 12 months up to now without any complications. In the control group (n = 5), esophageal epithelial was not observed on the luminal surface, constriction of the regenerated esophagus progressed and all the dogs died within 2 months after operation.</p><p><b>CONCLUSION</b>These observations suggest that this esophageal prosthesis made of composite biomaterials has high biocompatibility and potential for long-segment esophageal reconstruction, which is promising for the clinical repair of esophageal defects.</p>

Replacing dog cervical esophagus with polyurethane stent covered with collagen-chitosan sponge / 第二军医大学学报

Objective: To replace esophageal defects with artificially composed biodegradable materials and non-biodegradable materials. Met hods: A two-layered tube consisting of a collagen-chitosan sponge and an inner polyurethane stent was used to replace 5 cm esophageal segmental defect s in 15 dogs. The inner polyurethane stent was removed endoscopically at weekly intervals from 2 or 4 weeks. Results: Partial regeneration of es ophageal epithelia was observed in 5 dogs at week 2, and progressing constricti on occurred and the dogs became unable to swallow within 1 month. In the 10 dog s that the polyurethane stent was removed at week 4, regenerated esophageal tiss ue successfully replaced the defects, and complete epithelization was observed 1 month after surgery. Complete regeneration of esophageal mucosa structures, inc luding mucosal smooth muscle and mucosal glands were observed 3 months after surgery, and partial regeneration of esophageal muscle tissue was also observed 6 months after surgery. Conclusion: Our artificial prosthesis i n reconstruction of the cervical esophagus segment in dogs is feasible. Through temporary polyurethane tube, collagen-chitosan sponge provides a three-dimensi onal structure suitable for the regeneration and sufficient degradation time for the complete regeneration of esophagus.

Replacing dog cervical esophagus with polyurethane stent covered with collagen-chitosan sponge / 第二军医大学学报

Objective: To replace esophageal defects with artificially composed biodegradable materials and non-biodegradable materials. Met hods: A two-layered tube consisting of a collagen-chitosan sponge and an inner polyurethane stent was used to replace 5 cm esophageal segmental defect s in 15 dogs. The inner polyurethane stent was removed endoscopically at weekly intervals from 2 or 4 weeks. Results: Partial regeneration of es ophageal epithelia was observed in 5 dogs at week 2, and progressing constricti on occurred and the dogs became unable to swallow within 1 month. In the 10 dog s that the polyurethane stent was removed at week 4, regenerated esophageal tiss ue successfully replaced the defects, and complete epithelization was observed 1 month after surgery. Complete regeneration of esophageal mucosa structures, inc luding mucosal smooth muscle and mucosal glands were observed 3 months after surgery, and partial regeneration of esophageal muscle tissue was also observed 6 months after surgery. Conclusion: Our artificial prosthesis i n reconstruction of the cervical esophagus segment in dogs is feasible. Through temporary polyurethane tube, collagen-chitosan sponge provides a three-dimensi onal structure suitable for the regeneration and sufficient degradation time for the complete regeneration of esophagus.

Replacing dog cervical esophagus with polyurethane stent covered with collagen-chitosan sponge / 第二军医大学学报

Objective: To replace esophageal defects with artificially composed biodegradable materials and non-biodegradable materials. Met hods: A two-layered tube consisting of a collagen-chitosan sponge and an inner polyurethane stent was used to replace 5 cm esophageal segmental defect s in 15 dogs. The inner polyurethane stent was removed endoscopically at weekly intervals from 2 or 4 weeks. Results: Partial regeneration of es ophageal epithelia was observed in 5 dogs at week 2, and progressing constricti on occurred and the dogs became unable to swallow within 1 month. In the 10 dog s that the polyurethane stent was removed at week 4, regenerated esophageal tiss ue successfully replaced the defects, and complete epithelization was observed 1 month after surgery. Complete regeneration of esophageal mucosa structures, inc luding mucosal smooth muscle and mucosal glands were observed 3 months after surgery, and partial regeneration of esophageal muscle tissue was also observed 6 months after surgery. Conclusion: Our artificial prosthesis i n reconstruction of the cervical esophagus segment in dogs is feasible. Through temporary polyurethane tube, collagen-chitosan sponge provides a three-dimensi onal structure suitable for the regeneration and sufficient degradation time for the complete regeneration of esophagus.

Pulmonary apoptosis induced by ischemia-reperfusion lung injury in rats / 第二军医大学学报

Objective:To observe the pulmonary apoptosis resulted from ischemia reperfusion lung injury in rats. Methods: Forty male SD rats, weighing 300 350 g,were randomly divided into 8 groups: 6 ischemia reperfusion group,simple ischemia group and control group( n =5).An in situ ischemia reperfusion lung injury rat model was established. Apoptotic cells were detected by the terminal deoxynucleotidyl transferase mediate dUTP nick end labelling (TUNEL) technique and the apoptotic DNA fragments by pulmonary DNA electrophoresis. Electron microscopy was performed to verify the morphologic changes of apoptosis. Results: Obvious apoptosis of pneumocytes occurred early after(30 min) ischemia reperfusion lung injury, with the peak on 2 h after reperfusion, and there were no significant differences 12 h after reperfusion compared with control group. There was a slight but no statistically significant elevation of apoptotic pneumocytes number in simple ischemia group compared with controls. Conclusion: The result indicates that apoptosis may contribute significantly to ischemia reperfusion lung injury.

A comparison of 2 kinds of hydroxyapatite/collagen composites as tissue engineering scaffold / 第二军医大学学报

Objective:To prepare 2 composites using different proportions of hydroxyapatite and collagen and to assess their structural and biological properties, so as to pave a way for preparing tissue engineering chest wall scaffold.Methods: Two kinds of hydroxyapatite/collagen composites were prepared according to the weight ratios of 11 and 12; collagen sponge served as control. Then the structures of the 2 composites and the collagen sponge were observed under SEM. In vivo study was conducted to assess the biocompatibility and biodegradation of the composites by gross inspection and histological examination. Results: The collagen sponge had a 3-D network structure with fluey collagen fibers and poor mechanical strength, and its structure was damaged within 2 weeks after implantation and was completely absorbed 4 weeks later. The hydroxyapatite and collagen were well mixed in the composite with a hydroxyapatite to collagen ratio of 12; the composite had homogeneous 3-D porous structure (size of the pore being 100-400 m) and showed good biocompatibility: maintained its porous structure 4 weeks after implantation and was absorbed within 8 weeks. In composite with hydroxyapatite to collagen ratio of 11, the hydroxyapatite particles were separated from collagen fiber and conglomerated into masses, and the composite resulted in severe tissue reaction after implantation.Conclusion: When mixed with a reasonable proportion of hydroxyapatite, the collagen sponge has improved structure, biodegradable performance, and biocompatibility; the composite may be a novel scaffold for tissue engineering chest wall reconstruction.