BACKGROUND:Zinc-based alloy medical implant materials have excellent mechanical properties,complete degradability and good biocompatibility,and are mainly used in orthopedic implants,cardiovascular stents,bile duct stents,tracheal stents,nerve catheters,etc. OBJECTIVE:To review the research progress of biodegradable zinc-based alloys in bone defect repair and prospect the promising research direction and achievements of zinc-based materials. METHODS:After searching PubMed,Web of Science,WanFang Data,and CNKI databases from the establishment of the database to June 2023,various relevant articles on biodegradable zinc-based alloys for bone implant material research were collected.The basic characteristics of biodegradable zinc based alloys were summarized,and the role of zinc-based alloys in promoting bone tissue repair was sorted and summarized.The current research hotspots and shortcomings were discussed. RESULTS AND CONCLUSION:(1)Zinc-based alloys have good biocompatibility.Using zinc-based alloys as the matrix material,with the help of scaffold structure construction technology and coating optimization process,the bone conductivity of zinc-based alloys will be effectively improved,and their degradation products will have efficient bone induction to regulate the gene expression of osteoblasts and osteoclasts,thereby promoting the repair and reconstruction of bone defects.(2)However,in the research on optimizing zinc-based alloys,the coating process is relatively insufficient,and additive loading technology is still lacking.(3)Zinc-based alloys have excellent mechanical and biological properties.Through special processes,their bone conductivity and osteoinductivity can be increased to effectively improve their ability to promote bone repair and reconstruction,and it is expected to further achieve the development of personalized transplant materials.Further research and development are needed to optimize the integration of coating and additive loading technologies into zinc-based alloys.

Objective To evaluate the efficacy of locking compression plate (LCP) and retrograde intramedullary nail (RIMN) in the treatment of periprosthetic fractures after total knee arthroplasty (TKA),providing reference for surgeons to select the fixation approach.Methods Cochrane Library,PubMed,Embase,Medline,Wanfang database,VIP Database for Chinese Technical Periodicals,and China National Knowledge Infrastructure (CNKI) were searched to identify the retrospective comparison studies (RCS) which compared the clinical outcomes of LCP and RIMN for patients with periprosthetic supracondylar fractures of the distal femur after TKA.The quality of included literatures was evaluated by Newcastle-Ottawa scale(NOS).Meta-analysis was performed using Revman 5.3 software to compare the operation time,Knee society score (KSS),fracture healing time,nonunion rate,reoperation rate,and incidence of complications between the two groups.Results Ten retrospective comparison studies involving 487 patients were identified including LCP group (296 cases) and RIMN group (191 cases).The meta analysis results showed that no significant differences were found in the operation time (MD =10.89,95％ CI-9.56-31.33,P ＞ 0.05),KSS (MD =1.11,95％ CI-8.88-11.10,P =0.83),fracture healing time (MD =0.00,95％ CI-1.51-1.51,P ＞0.05),nonunion rate (OR =0.71,95％ CI 0.38-1.31,P ＞ 0.05),reoperation rate (OR =0.65,95％ CI 0.22-1.91,P ＞ 0.05),and complication incidence rate (0R=0.69,95％CI0.38-1.26,P＞0.05) between these two groups.Conclusions There are no significant differences in the operation time,KSS,fracture healing time,nonunion rate,reoperation rate,and complications between LCP and RIMN groups.LCP and RIMN have similar clinical outcomes in treating periprosthetic supracondylar femoral fracture following TKA.

To describe a novel particles surface display system which is consisted of gram-positive enhancer matrix (GEM) particles and anchor proteins for bacteria-like particles vaccines, we treated Lactobacillus rhamnosus GG bacteria with 10% heated-TCA for preparing GEM particles, and then identified the harvested GEM particles by electron microscopy, RT-PCR and SDS-PAGE. Meanwhile, Escherichia coli was induced to express hybrid proteins PA3-EGFP and P60-EGFP, and GEM particles were incubated with them. Then binding of anchor proteins were determined by Western blotting, transmission electron microscopy, fluorescence microscopy and spectrofluorometry. GEM particles preserved original size and shape, and proteins and DNA contents of GEM particles were released substantially. The two anchor proteins both had efficiently immobilized on the surface of GEM. GEM particles that were bounded by anchor proteins were brushy. The fluorescence of GEM particles anchoring PA3 was slightly brighter than P60, but the difference was not significant (P>0.05). GEM particles prepared from L. rhamnosus GG have a good binding efficiency with anchor proteins PA3-EGFP and P60-EGFP. Therefore, this novel foreign protein surface display system could be used for bacteria-like particle vaccines.

BACKGROUND:MicroRNAs (miRNAs) are widely involved in regulation of physiological processes, such as human development, cel proliferation, differentiation, and apoptosis, angiogenesis and lipid metabolism. MiRNAs also play an important regulating role in the pathological process of femoral head necrosis. At present, the research about the effect of icarin on miRNA expression in glucocorticoid- induced avascular necrosis is stil in the exploratory stage, and the specific targets, possible regulation mechanism and signaling pathway remain unclear.
OBJECTIVE:To explore the effect of icarin on miRNA expression of bone microvascular endothelial cels in steroids-induced human femoral head lesionsin vitro.
METHODS: Bone microvascular endothelial cels in cancelous bone of the femoral head were isolated and harvested in vitro. Icarin preconditioning preceded establishment of models of glucocorticoid-induced bone microvascular endothelial cel injury. Differential expression profiles and transcriptomes in glucocorticoid and normal groups were tested by miRNA microarrays. The most differentialy expressed miR-23b and miR-339 in microarray analysis were further confirmed by real-time quantitative PCR, Meanwhile the effects of icarin on the expression of miR-23b-5p and miR-339-5p were detected.
RESULTS AND CONCLUSION:According to the microarray analysis, one miRNA was up-regulated and four mi RNAs were down-regulated in the glucocorticoid group (fold > 2,P < 0.05). Results of RT-qPCR revealed that miR-23b was down-regulated and miR-339 up-regulated in the glucocorticoid group, which were in agreement with the microarray analysis (P < 0.05). Icarin pretreatment effectively prevented the imbalances of miR-23b expression induced by glucocorticoid (P < 0.01). These findings indicate that Icarin may participate in the pathological process of steroid-induced femoral head necrosis through regulating the expression of miR-23b.

BACKGROUNDWhat benefits and toxicities patients acquire from the use of bevacizumab combined with firstline chemotherapy remains controversial. This study was performed to evaluate the efficacy and safety of first-line chemotherapy plus bevacizumab in patients with metastatic colorectal cancer (mCRC).

METHODSSeveral databases, including PubMed, Embase, and Cochrane Library, were searched up to April 30, 2013. Eligible studies were only randomized, controlled trials (RCTs) with a direct comparison between mCRC patients treated with and without bevacizumab. Overall risk ratio (RR), hazard ratio (HR), odds ratio (OR), and 95% confidence intervals (CI) were calculated employing fixed or random-effects models depending on the heterogeneity of the included trials.

RESULTSSix RCTs, including 1582 patients in chemotherapy plus bevacizumab group and 1484 patients in chemotherapyalone group, were included. Overall, the addition of bevacizumab to first-line chemotherapy increased overall response rate (ORR) by 4.5%, prolonged both progression-free survival (PFS) and overall survival (OS), and increased the rate of total Grades 3 or 4 adverse events (G3/4AEs) by 6.9%. Significant differences were found in ORR (RR = 1.22 (95% CI 1.01-1.46), P = 0.03), PFS (HR = 0.60 (95% CI 0.47-0.77), P < 0.0001), OS (HR = 0.83 (95% CI 0.70-0.97), P = 0.02), and any G3/4AEs (OR = 1.56 (95% CI 1.29-1.89), P < 0.00001).

CONCLUSIONBevacizumab is a valuable addition to the current first-line chemotherapy regimens used in patients with mCRC, because of conferring a significant improvement in ORR, PFS, and OS, even though it increased adverse events.

Angiogenesis Inhibitors ; therapeutic use ; Antibodies, Monoclonal, Humanized ; therapeutic use ; Bevacizumab ; Colorectal Neoplasms ; drug therapy ; Humans ; Odds Ratio

BACKGROUNDThe incidence of total hip replacement in the younger and more active patients is ever increasing. The ceramic-on-ceramic (COC) bearing was developed to reduce wear debris-induced osteolysis and loosening and to improve the longevity of hip arthroplasties. Few studies have reported the clinical results and complications of the new zirconia-toughened ceramic total hip arthroplasty (THA).

METHODSA consecutive series of 132 young patients (177 hips) that underwent primary cementless THAs between January 2010 and December 2012 were included in this study. These arthroplasties all had fourth-generation COC bearings performed through a posterolateral approach. The average age was (41.8 ± 8.3) years (ranging from 22 to 55 years), and the mean follow-up period was (24.5 ± 9.4) months (ranging from 12 to 47 months). The results were evaluated both clinically and radiographically. Harris hip score (HHS) was determined before surgery and at the time of each follow-up. Presence of postoperative groin or thigh pain and squeaking were recorded. Other complications such as dislocations, periprosthetic fractures, and ceramic components fractures were diagnosed and treated in emergency.

RESULTSThe average HHSs improved from preoperative 60.3 ± 10.7 (ranging from 29 to 76) to 91.0 ± 5.1 (ranging from 74 to 100) at the final follow-up (t = 45.064, P < 0.05), and 97.7% of cases were scored as excellent and good results. At the last follow-up, incidental inguinal pain was found in three hips (1.7%) and thigh pain in 11 hips (6.2%). Radiographs showed a high rate of new bone formation around the acetabular and stem components. No obvious osteolysis or prosthesis loosening was detected. Complications occurred in six hips (3.4%): posterior dislocation in two hips (1.1%), periprosthetic femoral fracture in one hip (0.6%), asymptomatic squeaking in two hips (1.1%), and ceramic liner fracture in one hip (0.6%).

CONCLUSIONSThe fourth-generation COC THA showed excellent clinical results in younger active patients with no osteolysis-related prosthesis failure at a short-term follow-up study. Surgeons should still be aware of the potential risks of complications such as dislocation, periprosthetic fracture, squeaking, and ceramic components fracture.

Adult ; Arthroplasty, Replacement, Hip ; methods ; Ceramics ; Female ; Humans ; Male ; Middle Aged ; Young Adult

BACKGROUNDThe aim of this study was to determine the relationship between prosthesis coverage and postoperative hidden blood loss (HBL) in primary total knee arthroplasty (TKA).

METHODSA total of 120 patients who had undergone unilateral TKA from August 2012 to May 2013 were retrospectively studied. The Gross formula was used to calculate the amount of HBL. Routine standard anteroposterior (AP) and lateral X-ray films of the knee joint were taken postoperatively and used to measure the percentages of coronal femoral and of coronal and sagittal tibial prosthetic coverage. Then Pearson's correlation analysis was performed to assess the correlations between the percentages of prosthetic coverage for each AP and lateral position and HBL on the first and third postoperative days.

RESULTSThe volumes of HBL on the first and third postoperative days after TKA were (786.5 ± 191.6) ml and (1 256.6 ± 205.1) ml, respectively, and lateral X-ray film measurements of percentages of coronal femoral, tibial coronal, and sagittal prosthetic coverage were (87.9 ± 2.5)%, (88.5 ± 2.2)%, and (89.1 ± 2.3)%, respectively. Pearson's correlation analysis showed statistically significant correlations between percentages of total knee prosthetic coverage for each AP and lateral position and volumes of HBL on the first and third postoperative days (P < 0.05).

CONCLUSIONSHBL after TKA correlates with degree of prosthetic coverage. To some extent, the size of the surfaces exposed by osteotomy determines the amount of HBL. Choice of the appropriate prosthesis can significantly reduce postoperative HBL. Designing individualized prostheses would be a worthwhile development in joint replacement surgery.

Aged ; Aged, 80 and over ; Arthroplasty, Replacement, Knee ; adverse effects ; Female ; Humans ; Knee Joint ; surgery ; Male ; Middle Aged ; Postoperative Hemorrhage ; etiology ; Retrospective Studies

BACKGROUND:Corticosteroid-induced osteonecrosis of femoral head is one of the major causes of the loss of hip joint function. More and more studies have shown that corticosteroid-induced osteonecrosis of femoral head may be associated with proliferation ability of bone marrow mesenchymal stem cells.
OBJECTIVE:To detect the proliferation and differentiation ability of bone marrow mesenchymal stem cells isolated from patients with steroid-induced osteonecrosis of femoral head, providing rational evidences for treatment of corticosteroid-induced osteonecrosis of femoral head with the transplantation of autologous bone marrow containing bone marrow mesenchymal stem cells into the necrotic area of femoral head.
METHODS:Bone marrow mesenchymal stem cells from the femoral heads were col ected from patients with corticosteroid-induced osteonecrosis of femoral head, and new femoral neck fractures without osteonecrosis who were scheduled for total hip arthroplasty. In another group, bone marrow mesenchymal stem cells were col ected from ilium bone marrow of the same steroid-induced osteonecrosis of femoral head patients. The femoral neck fracture was defined as fracture without preceding trauma or in response to minimal trauma. Cases with corticoid treatment were excluded from the femur neck fracture patients. Al bone marrow mesenchymal stem cells were divided three groups:femoral neck fracture group;femoral head group of corticosteroid-induced osteonecrosis of femoral head;ilium group of corticosteroid-induced osteonecrosis of femoral head. The bone marrow mesenchymal stem cells were isolated by enzyme digestion or density gradient centrifugation from bone marrow blood of the three detecting area, and then selected by the adhesive method. Passage 3 bone marrow mesenchymal stem cells were selected for experiments.
RESULTS AND CONCLUSION:The results of methyl-thiazolyl-tetrazolium assay indicated that the bone marrow mesenchymal stem cells obtained from the femoral head group showed reduced proliferation ability compared with those obtained from the other two groups. The percentage of bone marrow mesenchymal stem cells was increased at G 0/G 1 , but decreased significantly at S+G 2/M in the femoral head group (P<0.05). The bone marrow mesenchymal stem cells obtained from the ilium group were proliferated best. The decreased proliferation ability of bone marrow mesenchymal stem cells may play a role in the low repair capacity of corticosteroid-induced osteonecrosis of femoral head, and bone marrow mesenchymal stem cells from the ilium of patients with corticosteroid-induced osteonecrosis of femoral head have a better proliferative ability.

BACKGROUND:It is a clinical difficult in the treatment of osteonecrosis with joint preservation, and to solve this problem, a variety of bone graft substitutes are at the exploration stage. OBJECTIVE:To evaluate the clinical outcome of lightbulb operation with porous bioceramic β-tricalcium phosphate in a consecutive series of patients with osteonecrosis of the femoral head. METHODS:From January to December 2008, 58 patients (88 hips) who had undergone lightbulb operation with porous bioceramic β-tricalcium phosphate were involved in this study. Al patients were evaluated both clinicaly and radiographicaly at postoperative 3, 6, 12 months and annualy. Functional improvement was assessed with the Harris hip score. RESULTS AND CONCLUSION: Among these patients, 56 patients (85 hips) were folowed up for 2-5 years. According to the ARCO staging system, there were 27 hips of stage II, 40 hips of stage IIIa, 18 hips of IIIb. According to the hospital’s classification, type C was in 4 hips, L1 in 15 hips, L2 in 28 hips, and L3 in 38 hips. According to the Harris hip score system, excelent outcome was in 55 hips, good in 12 hips, fair in 5 hips and poor in 13 hips. Nine of 11 patients who failed to preserve their own joints were subjected to hip replacement. The  mean preoperative and postoperative Harris scores were 61.2 and 85.3, respectively, with a mean improvement of 24.1 points (P < 0.001). All hips were radiologically stable, with no progress of osteonecrosis, and bone density in the bone graft area increased obviously. The replacement time of porous bioceramic β-tricalcium phosphate was 1-1.5 years. These findings suggest that the porous bioceramic β-tricalcium phosphate provides an option to treat osteonecrosis of the femoral head with satisfactory clinical outcomes, and profits the repair and reconstruction of femoral head osteonecrosis. When in the lateral column of femoral head, the porous bioceramic β-tricalcium phosphate can play a supporting role in the lateral column of the necrotic area, and further prevent collapse, which is suitable for patients with osteonecrosis of the femoral head, especially for those with joint preservation.

Objective To explore the regular progressive pattern of nontraumatic osteonecrosis of the femoral head (ONFH) in order to establish the reliable and convenient new classification of ONFH.Methods The coronal section of the femoral head was divided into three pillars (medial,central and lateral).The mid-coronal section of the femoral head on MRI was selected.The China-Japan Friendship Hospital (CJFH)classification of ONFH was established according to the site of necrotic focus in three pillars.A total of 153hips with ONFH were classified according to CJFH classification and Japanese Investigation Committee (JIC)classification,respectively.The collapse rate was observed and compared between both classifications of ONFH.Results The CJFH classification for ONFH consists of 3 types:type A,the medial pillar was involved; type B,the medial and central pillars were involved; type C,the lateral pillar was involved.According to site of necrosis focus in the lateral pillar,the type C was divided into 3 types:C1,there pillars were involved but there still was some normal tissue in lateral pillar;,C2,partial central pillar and all lateral pillar were involved; C3,the whole femoral head was involved.The natural history of the ONFH showed the collapse rate of type C2 and C3 in CJFH classification (95.3％) was higher than that (72.3％) of type C2 in JIC classification.Conclusion The CJFH classification of ONFH based on three pillars is more sensitive than JIC classification in predicting collapse of the femoral head.Moreover,the CJFH classification is convenient to use.