In vitro cytological comparison of osseointegration properties between biomimetic bone trabecular and regular porous structure / 西安交通大学学报(医学版)

【Objective】 To investigate the effects of biomimetic bone trabecular with the same porosity and pore size and regular porous structure on the adhesion, proliferation, and differentiation of osteoblasts, so as to provide theoretical basis for the improvement of osseointegration performance of titanium alloy implants. 【Methods】 The biomimetic bone trabecular and regular porous structures with the same porosity and pore size were generated by computer-aided software, and then processed into disc-shaped Ti6Al4V scaffolds with a diameter of 10 mm and a height of 3 mm by selective laser melting technology. MC3T3-E1 cells, the precursor cells of mouse osteoblasts in the logarithmic growth phase, were seeded on two kinds of scaffolds and divided into biomimetic bone trabecular group and regular porous structure group. After 3 hours of culture, acridine orange staining and phalloidin /DAPI staining were used to evaluate the number of cell adhesion. After 3 days of culture, the scaffolds were examined by scanning electron microscopy to evaluate the adhesion state of cells. After 1, 3, and 5 days of culture, the scaffolds were taken for CCK8 detection to observe the proliferation of cells. After 7 and 14 days of differentiation, alkaline phosphatase (ALP) activity was detected. After 14 days of differentiation, the expressions of osteogenesis-related genes (ALP, OCN, RUNX2) were detected by RT-PCR. After 30 days of differentiation, the scaffolds were stained with alizarin red and 100 g/L cetylpyridinium chloride was used to dissolve mineralized nodules. Calcium salt deposition was qualitatively and quantitatively detected to evaluate cell differentiation. 【Results】 The results of acridine orange and phalloidin /DAPI staining showed that the biomimetic trabecular Ti6Al4V scaffold adhered to more MC3T3-E1 cells than the regular porous structure, and the cytoskeleton of the former scaffold was more densely distributed. The results of scanning electron microscopy showed that the pseudopodia of MC3T3-E1 cells on the biomimetic bone trabecular Ti6Al4V scaffold were longer and the extension state was better than that of the regular porous structure. CCK8 test showed that the proliferation of MC3T3-E1 cells on the biomimetic trabecular bone titanium alloy scaffold was significantly higher than that on the regular porous structure on the 3rd and 5th day, and the difference gradually increased with the increase of time, with statistical significance (P<0.05). The results of cell differentiation test showed that ALP activity on the bionic trabecular scaffold was higher than that on the regular porous structure (P<0.05). The expressions of osteogenic genes (ALP, OCN, RUNX2) in MC3T3-E1 cells on the biomimetic bone trabecular titanium alloy scaffold were significantly higher than those on the regular porous structure (P<0.05). After 30 days of induction, the amount of calcium salt deposited in the bionic trabecular titanium alloy scaffold was significantly larger than that in the regular porous structure (P<0.05). 【Conclusion】 The biomimetic bone trabecular with a porosity of 65% and an equivalent pore size of 600 μm is more conducive to the adhesion, proliferation and differentiation of mouse osteoblast precursor cells MC3T3-E1 on the titanium alloy scaffold than the regular porous structure with the same porosity and pore size. It is theoretically more conducive to improving the osseointegration performance of titanium alloy implants.

Measuring Glutathione Regeneration Capacity in Stem Cells

Glutathione (GSH) is a chief cellular antioxidant, affecting stem cell functions. The cellular GSH level is dynamically altered by the redox buffering system and transcription factors, including NRF2. Additionally, GSH is differentially regulated in each organelle. We previously reported a protocol for monitoring the real-time GSH levels in live stem cells using the reversible GSH sensor FreSHtracer. However, GSH-based stem cell analysis needs be comprehensive and organelle-specific. Hence, in this study, we demonstrate a detailed protocol to measure the GSH regeneration capacity (GRC) in living stem cells by measuring the intensities of the FreSHtracer and the mitochondrial GSH sensor MitoFreSHtracer using a high-content screening confocal microscope. This protocol typically analyses the GRC in approximately 4 h following the seeding of the cells onto plates. This protocol is simple and quantitative. With some minor modifications, it can be employed flexibly to measure the GRC for the whole-cell area or just the mitochondria in all adherent mammalian stem cells.

Drug resistance and molecular typing of diarrheagenic escherichia coli from the diarrhea clinics in Qingpu District, Shanghai / 中华预防医学杂志

Objective: To analyze the drug resistance and multilocus sequence typing of five types of diarrheagenic Escherichia coli (DEC) isolated from diarrhea outpatients of diarrhea comprehensive monitoring designated hospital in Qingpu District, Shanghai from 2015 to 2019. Methods: From January 2015 to December 2019, five types of DEC, isolated and identified from diarrhea outpatient cases' anal swabs of the Qingpu branch of Zhongshan Hospital were collected to determine the minimal inhibitory concentration by using the micro broth dilution susceptibility test. The strains, resistant to the third-generation cephalosporins or carbapenems, or producing ESBLs, were selected based on the results of sensitivity tests and determined by WGS. The MLST typing of DEC was analyzed based on the WGS technology and the minimum spanning tree was constructed by BioNumerics 7.6 software to analyze the local dominant flora. Results: A total of 513 strains of DEC were detected and isolated from 4 494 anal swabs, with a detection rate of 11.42%. About 500 strains were tested for drug sensitivity to nine antibiotics in four classes, including 330 strains of enterotoxigenic E.coli (ETEC), 72 strains of enteroaggregative E.coli (EAEC), 95 strains of enteropathogenic E.coli (EPEC), 1 strain of enterohemorrhagic E.coli (EHEC), and 2 strains of enteroinvasive E.coli (EIEC). From 2015 to 2019, the resistance rate of cefotaxime-clavulanic acid was significantly different (P<0.05). The resistance rate of virulence types of DEC to nalixic acid was significantly different (P<0.05). About 71 strains of DEC were determined by WGS, and 77 drug-resistant genes were detected. Strains were classified into 32 ST subtypes, with the dominant genotypes being ST-1491 (29.6%, 21/71) and ST-10 Complex (23.9%, 17/71). All ST-1491 produced ESBLs, which were blaCTX-M gene mutant strains. The dominant type of ST-10 complex was ST-218 (35.3%, 6/17). In addition, 8 strains of EAEC, 14 strains of EPEC and 49 strains of ETEC were classified into 7, 14 and 18 ST subtypes, respectively. Conclusion: The drug resistance of DEC strains from the diarrhea outpatient case of Qingpu District is serious. The ST types of EAEC and EPEC are highly polymorphic. The dominant ST types of DEC are basically consistent with the common genotypes in southeast China.

Investigation on the Influence of Medical Postgraduates' Awareness of Mental Health Knowledge on Discrimination against Patients with Mental Disorders / 中国医学伦理学

Objective:To explore the discrimination against the patients with mental disorders and current situation of awareness of mental health knowledge of medical postgraduates and their relationship.Methods:A questionnaire survey was conducted among 132 medical postgraduates in October 2016 using the assessment scale of discrimination against patients with mental disorders and mental health knowledge awareness questionnaire,which derived from mental health work indicators survey and evaluation program issued by the General Office of the Ministry of Health in 2010.Results:There was significant gender difference (P ＜0.01)in the overall score and the score of each dimension of assessment scale of discrimination against patients with mental disorders,and the score of mental health knowledge was (13.93-± 3.13).There was significant negative correlation between scores of assessment scale of discrimination against patients with mental disorders and mental health knowledge.Multiple linear regression analysis showed that awareness of mental health knowledge could predict the discrimination against the patients with mental disorders and all its factors.Conclusion:Awareness of mental health knowledge in medical post graduates can predict the discrimination against the patients with mental disorders.Medical universities should carry out corresponding education and publicity work with pertinence.

Ligamentization of Autogenous Hamstring Grafts after Anterior Cruciate Ligament Reconstruction / 中国运动医学杂志

Objective To investigate the ligamentization process of autogenous hamstring grafts after anterior cruciate ligament (ACL)reconstruction and explore its potential influencing factors.Methods Patients undergoing the ACL reconstruction between January and December 2014 were recorded demographic data including their gender,age,weight,height,body mass index (BMI),general joint relaxation(the Beighton score),and their surgical duration.Six,12,and 24 months after the operation,the signal intensity of the proximal,middle and distal part of the ACL grafts was measured using MRI,and the signal to noise quotient (SNQ)was calculated to assess the graft maturity.The data were analyzed statistically to explore the ligamentization process of grafts and its potential influencing factors.Results A total of 87 patients receiving ACL reconstruction were enrolled in this study.The results showed that the SNQ of the proximal and middle part of the ACL grafts decreased gradually with time,and significant differences were observed in the SNQ value of the proximal part between 24 months and that of 6 and 12 months(P＜0.05).There was no significant difference in the SNQ value of the distal part at different time points.The SNQ values of grafts were not significantly affected by the gender,age,body weight,height,BMI,Beighton score or ACL duration(P＞0.05).Conclusion The ligamentization of autogenous hamstring grafts after ACL reconstruction increases gradually with timent positive correlation with postoperative time.

Comparison of the clinical features and treatment outcomes of oral and maxillofacial space infection between diabetic and non-diabetic patients / 实用口腔医学杂志

Objective:To review and compare the clinical features and treatment outcomes of oral and maxillofacial space infection (OMSI)between diabetic and non-diabetic patients.Methods:Clinical data of 43 diabetic patients with OMSI(simultaneoustly treated by blood sugar control)and 84 of non-diabetic patients with OMSI were reviewed,the clinical features and treatment outcomes were compared.Statistical analyses were conducted by T test,the chi square test and variance analysis.Results:Diabetic patients with OM-SI were older(P =0.000),had more spaces involved concurrently(P =0.035 )and had higher blood sugar at presentation(P =0.000).There was no significant difference between groups about the use and change of antibiotics,the incision times,hospital stay durition and the incidence of the complications.Conclusion:The prognosis of the diabetic patients with OMSI under the strict control of the blood glucose concentration has no significant difference from the non-diabetic patients with OMSI.Diabetic patients with OMSI have older age and more spaces involved,and special attention should be paid.

A retrospective study of 1 009 patients with oral and maxillofacial fresh trauma / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To analyze the epidemiological characters of fresh maxillofacial fractures in hospitalized patients by the retrospective study.</p><p><b>METHODS</b>From Jan. 2008 to Dec. 2013, a total of 1 009 patients with fresh maxillofacial fractures treated at Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology were investigated. The data were statistically analyzed by SPSS 21.0.</p><p><b>RESULTS</b>The male and female ratio was 2.94:1 and 33.5% of the patients aged from 20 to 30 years. The most common cause of the fresh fracture was road traffic accidents (424 cases, 42.0%), followed by tumblings (250 cases, 24.8%) and violence (128 cases, 12.7%). The number of new fracture was increasing gradually in recent years. The patients were at peak of 20-29 years old. The mandibular fracture was the most frequently seen (536 cases, 53.1%), followed by zygomatic complex fractures (233 cases, 23.1%). The simple maxillary fracture was rare and usually combined with other fractures. Infraorbital nerve injury was the most common one in nerve injuries (144 cases). The most common associated injury was extremity injuries (77 cases), followed by thoracic injury (65 cases) and craniocerebral injury (57 cases). Associated injuries were mostly caused by car accidents (127 sites), followed by fall (32 sites). Logictic regression analysis showed that fall and tumbling were risk factors of mandibular and condylar fracture (OR > 1, P < 0.05), while age was a protective factor (OR > 1, P < 0.05).</p><p><b>CONCLUSIONS</b>Oral and maxillofacial fresh fractures most commonly occurred in young people, and the most common cause of fractures was road traffic accidents. Infraorbital nerve was involved frequently. The most common associated injuries was extremity injuries.</p>

A comparative study of three maxillofacial trauma scoring systems in mandible fracture grading / 实用口腔医学杂志

Objective:To compare 3 maxillofacial trauma scoring systems in mandible fracture grading.Methods:Maxillofacial Injury Severity Score(MISS),Maxillofacial Injury Severity Score(MFISS),Mandible Injury Severity Score(S5)were used in the analysis of mandible fracture severity in 313 cases with mandible fractures.The results were statistically analyzed.Results:S5 score showed higher correlation with operation time,operation charge and hospitalization expenses than MFISS and MISS,and it could distinguish single and multiple mandible fractures effectively.It was also a significant factor affecting the cost of hospitalization.Conclusion:The Mandible Injury Severity Score was more suitable for the scoring of mandible fracture.

Correction of enophthalmos following orbital fracture with computer-assisted navigation system / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To evaluate the efficiency of individually fabricated titanium mesh to correct enophthalmos following orbital fracture by using computer-assisted navigation system.</p><p><b>METHODS</b>Forty- nine patients with unilateral orbital fracture were divided into navigation group (25 cases) and non-navigation group (24 cases). All patients underwent orbital reconstruction to correct post-traumatic enophthalmos with individually fabricated titanium mesh. The bilateral global projection and the orbital volumn were measured preoperatively and postoperatively. The depth of titanium mesh was measured postoperatively.</p><p><b>RESULTS</b>Statistical analysis demonstrated the global projection at the affected side increased by (3.35 ± 1.46) mm in navigation group and by (2.25 ± 1.14) mm in non- navigation group postoperatively, and there was a significant difference between the two groups (P < 0.05). The orbital volumn at the affected side decreased by (5.94 ± 2.20) ml in navigation group and by (4.21 ± 2.18) ml in non-navigation group, and there was a significant difference between the two groups (P < 0.05). The depth of titanium was (31.95±2.97) mm in navigation group and (29.27±2.72) mm in non-navigation group, and the values between the two groups differed significantly (P < 0.05).</p><p><b>CONCLUSIONS</b>The use of computer-assisted navigation for the orbital wall reconstruction with individually fabricated titanium mesh can protect the optic nerve reliably and achieve satisfactory results.</p>

Anti-gastric cancer effect of melatonin and Bcl-2, Bax, p21 and p53 expression changes / 生理学报

In order to investigate the role of melatonin in inhibiting the proliferation of murine gastric cancer and the underlying molecular mechanism, we performed an in vivo study by inoculating murine foregastric carcinoma (MFC) cells in mice, and then tumor-bearing mice were treated with different concentrations of melatonin (i.p.). The changes of Bcl-2, Bax, p21 and p53 expressions in tumor tissue were detected by using real-time fluorescence quantitative RT-PCR and Western blot. We found that: (1) melatonin resulted in reductions of tumor's volume and weight in the gastric cancer-bearing mice and thus showed anti-cancer effect; (2) melatonin reduced Bcl-2 expression, but increased the expression of Bax, p53 and p21 in tumor tissue. Our results suggest that melatonin could inhibit the growth of tumors in gastric cancer-bearing mice through accelerating the apoptosis of tumor cells.

Intraoperative study on anthropometry and gender differences of the proximal tibial plateau at the arthroplasty resection surface / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The tibial plateau is asymmetric with a larger medial plateau. We observed from clinical practice that the shape of the tibial plateau does not always present a larger medial plateau. Tibial plateau also showed other shapes. The purpose of this study was to analyze the anthropometric data of the proximal tibia in a large group of Chinese patients undergoing total knee arthroplasty and to investigate the morphology of the resected proximal tibial surface and its gender differences.</p><p><b>METHODS</b>A total of 822 knees (164 males, 658 females) from the Chinese population were measured intraoperatively for medial anteroposterior (MAP) and lateral anteroposterior (LAP) dimensions of the resected proximal tibial surface. The difference of MAP and LAP (DML) was also calculated as MAP minus LAP. We then classified the data into three groups based on the DML (<-2, -2 to 2, and >2 mm) to analyze the morphology of the proximal tibia and its distribution between male and female.</p><p><b>RESULTS</b>The shape of proximal tibial plateau was of three types: larger medial plateau type, symmetric type, and larger lateral plateau type. There were significant differences between males and females in relation to the shape distribution of the proximal tibial plateau (P < 0.05). Most of the proximal tibial plateau was asymmetric, with 517 of 822 (62.9%) tibia having a DML >2 mm and 120 of 822 (14.6%) tibia having a DML<-2 mm. Only 185 of 822 (22.5%) tibia had a DML between -2 and 2 mm.</p><p><b>CONCLUSION</b>The results of this study can be used as a guideline to design tibial components with different DMLs to better match the different anthropometry of the resected tibial surface.</p>

Inhibitory effect of melatonin on murine foregastric carcinoma cells via membrane receptors MT2 / 解剖学报

Objective To investigate the inhibitory effect of melatonin on the proliferation activity of murine foregastic carcinomac ( MFC) cells via melatonin membrane receptors MT 2 and its relationship with the signaling pathways of mitogen-activated protein kinases ( MAPKs), phosphatidylinositol 3-kinase ( PI3K)-Akt.Methods Using siRNA technology to silence MT2 expression, we examined the ability of melatonin to inhibit the proliferation activity of MFC cells and its influence on the phosphorylation of ERK 1/2 and Akt.Results We found two interesting effects of SiRNA-mediated silencing of MT2 expression.Firstly, it significantly antagonized the inhibitory effect of melatonin on the proliferation activity of MFC cells .Secondly , it partially blocked the inhibitory effect of melatonin on the phosphorylation of ERK 1/2 and Akt.Conclusion Our results suggest that melatonin can inhibit the phosphorylation of ERK 1/2 and Akt via MT2 receptors , thereby inhibiting the proliferation of gastric cancer cells .

Remnant-preserving posterior cruciate ligament reconstruction with graft tension-relieving: a comparative study with conventional technique / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Posterior cruciate ligament (PCL) tear is a severe injury to the knee joint and often requires surgical reconstruction. A number of PCL reconstruction techniques have been reported. However, the problem of residual laxity after surgery is not unusual with conventional techniques. This study aims to introduce a modified PCL reconstruction with remnant preservation and graft tension relieving.</p><p><b>METHODS</b>Between December 2008 and June 2011, 36 cases of PCL reconstruction were performed in our institute, 20 with conventional technique (Group I) and 16 with modified technique (Group II). Pre- and post-operative results of the international knee documentation committee knee evaluation form (IKDC), Lysholm, Tegner, and KT2000 side-to-side difference were obtained.</p><p><b>RESULTS</b>Significant improvements of IKDC, Lysholm, Tegner, and KT2000 results after surgery were found in both groups. Group II showed better improvement in all subjective examinations and significantly more decrease of KT 2000 side-to-side difference.</p><p><b>CONCLUSION</b>Modified PCL reconstruction with remnant preservation and graft tension relieving showed better results in restoration of posterior stability compared to conventional technique.</p>

Use of computer-assisted navigation system in reconstruction of unilateral old zygomatic complex fracture / 中华创伤杂志

Objective To investigate whether the surgery resorting to computer-assisted navigation system (CANS) can enhance effects in managing unilateral old zygomatic complex (ZMC) fracture in comparison with conventional surgery.Methods Twenty-four patients with unilateral old ZMC fracture for which surgical correction was wanted were divided into study group (n =12,treated with navigational surgery) and control group (n =12,treated with traditional surgery) in the 1 ∶ 1 matched case-control study.Therapeutic effects of CANS were evaluated by postoperative CT measurement,subjective satisfaction questionnaire and clinical examination.Results According to postoperative three-dimensional CT measurement,the mean projection and width differentials of bilateral zygomatic bones were 1.58 mm and 1.47 mm in study group,3.58 mm and 3.63 mm in control group,with significant differences between groups.No complications occurred within three months of follow-up.Moreover,the patients in study group were all satisfied with the treatment,but two patients in control group desired further surgery to ameliorate zygomatic shape.Conclusion Surgery with application of CANS improves efficacy of treatment for unilateral old ZMC fracture.

Application of computer navigation system in the treatment of post-traumatic reconstruction / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the value of computer aided navigation system (CANS) in the treatment of post traumatic maxillofacial deformation.</p><p><b>METHODS</b>Fifty-four patients (M = 37, F = 17) were included in the study, including 31 cases of zygomatic fracture, 7 cases of pure orbital fracture, 11 cases of temporal mandibular joint ankylosis, 1 case of foreign body and 4 cases of defect reconstruction with custom implant. Data acquisition was done through CT scan, and DICOM data was transferred into workstation. Computer assisted design, including osteotomy, reposition, fibula flap design, orbital implant construction was performed using Surgicase CMF and Brain Lab Iplan system. The virtual design was transferred to Brain Lab navigation system, and the osteotomy, reduction, location of bone graft and custom implant were guided by navigation. Postoperative CT scan was required 48 - 72 hours after surgery. Preoperative and postoperative CT images were superimposed automatically in BrainLab Iplan system, and compared both in 3D objects and 2D slices.</p><p><b>RESULTS</b>All the cases achieved good results without serious complication. The error of important corresponding points in zygomatic fracture reduction, orbital reconstruction and defect reconstruction was 0.2 - 3.5 mm, 0.8 - 2.0 mm and 0.2 - 2.2 mm respectively.</p><p><b>CONCLUSIONS</b>Computer assisted design is of considerable value for the systematic and accurate planning for complicated post traumatic deformation. Virtual plan could be carried out accurately with the assistance of CANS.</p>

Evaluation of the navigation system for orbital wall reconstruction in unilateral orbital fractures / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To evaluate the efficiency of navigation system for orbital wall reconstruction in unilateral orbital fractures.</p><p><b>METHODS</b>Fifteen patients (7 male and 8 female) with unilateral orbital fracture underwent orbital reconstruction with the help of intraoperative navigation system. The average age was 34.3 ± 9.5 years. All patients underwent spiral CT scanning preoperatively, and the CT data was imported to the BrainLab navigation system (Germany, BrainLab company). The orbit of the intact side was mirrored to the opposite side as the reference for pre-operative planning. The titanium mesh was mounted on the resin template made by rapid prototyping machine based on the mirrored CT data. When the injury was limited, the hydroxyapatite sheet was used for the orbital wall reconstruction. During the operation, the real-time navigation helped to ensure precise placement. The re-establishing result was assessed based on the postoperative CT data with the following four variables: the volumetric difference between the bilateral orbit, the volume of the herniated soft tissue, the global projection and the discrepancy between the simulated and the achieved position of the reconstructed orbital wall. The reconstructive discrepancy was measured only in the titanium plate grafting cases.</p><p><b>RESULTS</b>There were no serious complications such as infection, graft rejection and optic nerve injury in any case. Preoperatively, the average degree of enophthalmos was (3.5 ± 1.6) mm, the average volumetric difference between the injured and the unaffected orbit was (4.5 ± 1.8) ml, and the average volume of the herniated orbital soft tissue was (2.1 ± 0.7) ml. Postoperatively, the three values were respectively reduced to (1.3 ± 0.6) mm, (1.8 ± 0.9) ml and (0.7 ± 0.3) ml. The discrepancy of the medial and inferior wall were (2.5 ± 0.6) mm and (2.1 ± 0.4) mm.</p><p><b>CONCLUSIONS</b>The intraoperative use of navigation system for the orbital wall reconstruction in unilateral orbital fractures can provide reliable accuracy and achieve satisfactory results.</p>

Sex, age, and annual incidence of primary total knee arthroplasty: a university affiliated hospital survey of 3118 Chinese patients / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>In recent years, the number of patients undergoing primary total knee arthroplasty in China has rapidly increased. However, the incidence of primary total knee arthroplasty is unknown. The purpose of this study was to investigate the sex, age and, annual incidence of primary total knee arthroplasty based on 3118 Chinese patients who underwent the procedure during the period of 2000 - 2011.</p><p><b>METHODS</b>Total knee arthroplasties were performed on 511 males and 2607 females in our hospital during the period of 2000 - 2011. The sex, age, and annual incidence of primary total knee arthroplasty were evaluated.</p><p><b>RESULTS</b>The annual incidence of primary total knee arthroplasty increased from 35 knees in 2000 to 681 knees in 2011. The average annual percentage increase in incidence was 33.2%. Females accounted for 83.2% of the patients who underwent primary total knee arthroplasty. In both males and females, the highest incidence was observed in the group aged 65 - 74 years.</p><p><b>CONCLUSIONS</b>This study demonstrated a rapid increase in the incidence of primary total knee arthroplasty in our Chinese study population. The sex and age incidence of primary total knee arthroplasty in our study population differed from those reported in Western populations.</p>

Second-look arthroscopic evaluation of the articular cartilage after primary single-bundle and double-bundle anterior cruciate ligament reconstructions / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Several reports have shown the progression of articular cartilage degeneration after anterior cruciate ligament (ACL) reconstruction. No report has been published about the cartilage comparing changes after single-bundle (SB) and double-bundle (DB) ACL reconstructions. The purpose of this study was to evaluate the articular cartilage changes after SB and DB ACL reconstructions by second-look arthroscopy.</p><p><b>METHODS</b>Ninety-nine patients who received arthroscopic ACL reconstruction were retrospectively reviewed at an average of 14 months after reconstruction, 58 patients underwent SB ACL reconstruction and 41 patients underwent DB ACL reconstruction. Hamstring tendon autografts were used in all patients. Second-look arthroscopy was done in conjunction with the tibial staple fixation removal at least one year after the initial ACL reconstruction. Arthroscopic evaluation and grading of the articular cartilage degeneration for all patients were performed at the initial ACL reconstruction, and at the second-look arthroscopy.</p><p><b>RESULTS</b>The average cartilage degeneration at the patellofemoral joint (PFJ) was found significantly worsened after both SB and DB ACL reconstructions. This worsening were not seen at medial tibiofemoral joint (TFJ) and lateral TFJ. Grade II cartilage damage was the most common. At second-look arthroscopy, the average patellar cartilage degeneration was 1.14 ± 0.14 (at first look 0.52 ± 0.11) for the SB group, and 1.22 ± 0.15 (at first look 0.56 ± 0.12) for the DB group. The average trochlear cartilage degeneration was 1.05 ± 0.16 (at fist look 0.10 ± 0.06) and 0.66 ± 0.17 (at fist look 0.17 ± 0.09), respectively. The average patellar cartilage degeneration showed no significant difference in both groups. However, the average trochlea cartilage degeneration in DB group was significantly less than in SB group.</p><p><b>CONCLUSIONS</b>Patellofemoral cartilage degeneration continued to aggravate after ACL reconstruction. DB ACL reconstruction could significantly decrease the trochlea cartilage degeneration compared with SB ACL reconstruction.</p>

Effect of morphine postconditioning on myocardial ischemia-reperfusion injury in rabbits / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the protective effects of morphine postconditioning on myocardial ischemia-reperfusion (I/R)injury and the potential mechanisms in rabbits.</p><p><b>METHODS</b>Thirty-two New Zealand male white rabbits were randomly assigned into 4 groups: Group 1 (Sham), Group 2 (I/R), Group 3 (ischemic postconditioning), Group 4 (ischemia and morphine postconditioning). Group 1 was perfused for 160 min; Group 2 underwent 40 min ischemia and 120 min reperfusion; Group 3 underwent three cycles of 30 s reperfusion and 30 s left anterior descending coronary artery re-occlusion immediately after 40 min ischemia and before 120 min reperfusion; Group 4 was given morphine 1.0 mg/kg immediately after 40 min ischemia in 1 min and before 120 min reperfusion. Blood samples were taken from arterial line at 20 min before occlusion, 20 min after occlusion, 40 min after occlusion, 1 h after reperfusion and 2 h after reperfusion for determination of the plasma levels of cardiac troponin I (cTnI). At the end of the reperfusion, infarct size (IS) and area at risk were defined by Evans and TTC staining. Plasma SOD activity and MDA were determined at the end of reperfusion.</p><p><b>RESULT</b>The levels of cTnI were significantly lower during reperfusion in the two postconditioning groups than those in I/R group. The plasma MDA content was significantly lower and SOD activity was significantly higher in the two postconditioning groups than those in I/R group, but there was no difference between two postconditioning groups. Morphine significantly reduced infarct size of the left ventricular area at risk as compared with I/R group (P<0.05).</p><p><b>CONCLUSION</b>Morphine postconditioning is as effective as ischemic postconditioning in the protection of myocardium against I/R injury in rabbits. Decrease in oxygen free radicals and increased antioxidant activity might be involved in its mechanism.</p>

Clinical research on revision after anterior cruciate ligament reconstruction / 中华外科杂志

<p><b>OBJECTIVE</b>To analyze the management principle of revision after anterior cruciate ligament (ACL) reconstruction and the factors contributing to its result.</p><p><b>METHODS</b>The data of 12 patients who received revision after ACL reconstructions from November 2001 to July 2006 were studied retrospectively. The indication of the operation, the management during the procedure and the clinical results were analyzed.</p><p><b>RESULTS</b>All the patients had pathological instability after primary ACL reconstructions. In this group, 2 cases received primary bone transplantation. The other 10 cases received primary ACL revision. Among them, 4 cases were reconstructed with STG obtained from the same lateral, 4 cases were obtained from the opposite lateral, 1 case was reconstructed with bone-patellar tendon-bone (B-PT-B) obtained from the same lateral, and 1 case was reconstructed with iliotibial tractus. One year later, the mean side-to-side difference of KT-2000 examination were 1.6 mm and 3.1 mm at 90 degrees and 30 degrees. The mean IKDC, Lysholm and Tegner scores were 72.8, 78.3 and 4.9.</p><p><b>CONCLUSIONS</b>The functional results and objective stability could be obtained through revision ACL reconstruction. However, outcomes are less favorable than those with primary reconstructions, which might be related to the factors including deficiency of previous surgery and impact of revision procedure.</p>