Controlled Release of TGF-ß3 for Effective Local Endogenous Repair in IDD Using Rat Model.

Introduction: Intervertebral disc (IVD) degeneration (IDD) is one of the most widespread musculoskeletal diseases worldwide and remains an intractable clinical challenge. Currently, regenerative strategies based on biomaterials and biological factors to facilitate IVD repair have been widely explored. However, the harsh microenvironment, such as increased ROS and acidity, of the degenerative region impedes the efficiency of IVD repair. Here, an intelligent biodegradable nanoplatform using hollow manganese dioxide (H-MnO2) was developed to modulate the degenerative microenvironment and release transforming growth factor beta-3 (TGF-ß3), which may achieve good long-term therapeutic effects on needle puncture-induced IDD. Methods: Surface morphology and elemental analysis of the MnO2 nanoparticles (NPs) were performed by transmission electron microscopy and an energy-dispersive X-ray spectroscopy detector system, respectively. The biological effects of MnO2 loaded with TGF-ß3 (TGF-ß3/MnO2) on nucleus pulposus cells (NPCs) were assessed via cytoskeleton staining, EdU staining, qPCR and immunofluorescence. The efficacy of TGF-ß3/MnO2 on needle puncture-induced IDD was further examined using MRI and histopathological and immunohistochemical staining. Results: The MnO2 NPs had a spherical morphology and hollow structure that dissociated in the setting of a low pH and H2O2 to release loaded TGF-ß3 molecules. In the oxidative stress environment, TGF-ß3/MnO2 was superior to TGF-ß3 and MnO2 NPs in the suppression of H2O2-induced matrix degradation, ROS, and apoptosis in NPCs. When injected into the IVDs of a rat IDD model, TGF-ß3/MnO2 was able to prevent the degeneration and promote self-regeneration. Conclusion: Use of an MnO2 nanoplatform for biological factors release to regulate the IDD microenvironment and promote endogenous repair may be an effective approach for treating IDD.

Curettage through a wide cortical window for treatment of a primary aneurysmal bone cyst of the patella.

A 27-year-old man presented with intermittent right knee pain for 1 year with no previous trauma. Physical examination revealed only tenderness over the patella. Typical fluid-fluid levels were visible on magnetic resonance imaging (MRI), which highly suggested aneurysmal bone cyst (ABC) of the patella. After removal of a large window of thin cortical bone, curettage and bone grafting followed by cerclage wiring was performed. Histology confirmed the initial diagnosis of primary ABC of the patella. At the final follow-up visit at 71 months after surgery, the patient had normal joint activity with no pain or evidence of recurrence. Previous publications indicated patellectomy in the initial series, but curettage and bone grafting have more recently provided excellent results and good graft incorporation in most cases, even for aggressive lesions. In our patient, thorough curettage and bone grafting through a wide cortical window followed by cerclage wiring fixation and figure-eight sutures was a successful treatment option for primary ABC of the patella without articular disruption.

Mesenchymal stem cells-derived exosomes ameliorate nucleus pulposus cells apoptosis via delivering miR-142-3p: therapeutic potential for intervertebral disc degenerative diseases.

Intervertebral disc degeneration (IDD) is the main cause of lower back pain (LBP), and puzzles massive individuals worldwide. Mesenchymal stem cells (MSCs) transplantation has been demonstrated to potentially ameliorate IDD progression, while the underlying mechanism has not been fully explained. Interleukin-1ß (IL-1ß) was used to induce nucleus pulposus cells (NPCs) injury. Bone marrow MSCs-derived exosomes were isolated using the super centrifugation method, and characterized using Transmission electron microscopy (TEM) and western blot. Cell viability was determined by MTT, while apoptosis was measured by Annexin-V staining using flow cytometry. miR-142-3fp and gene expressions were measured by real-time PCR. The protein expressions were determined by western blot. Herein, we found exosomes from bone marrow MSCs are circular vesicles, about 80 nm in diameter, and with robust expression of TSG101 and CD63, but without of Calnexin. MSCs exosomes alleviated NPCs apoptosis by reducing IL-1ß-induced inflammatory cytokines secretion and MAPK signaling activation. Additionally, MSCs exosomes inhibited NPCs apoptosis and MAPK signaling by delivering miR-142-3p that targets mixed lineage kinase 3 (MLK3). Overexpression of MLK3 abolished the effects of MSCs exosomes on the inflammatory condition, cell apoptosis, and MAPK signaling activation in NPCs. The results confirmed that bone marrow MSCs-derived exosomes-packaged miR-142-3p alleviates NPCs injury through suppressing MAPK signaling by targeting MLK3. The work highlights the therapeutic effect of MSCs on IDD progression, and bone marrow MSCs exosomes might be apromising therapeutic strategy for IDD.

Copper-Catalyzed One-Pot Synthesis of 1,3-Enynes from 2-Chloro-N-(quinolin-8-yl)acetamides and Terminal Alkynes.

A method for the chemo-, regio-, and stereoselective one-pot synthesis of 1,3-enynes is described. The reaction of 2-chloro-N-(quinolin-8-yl)acetamides with terminal alkynes proceeds smoothly in the presence of a copper catalyst at room temperature to produce (E)-1,3-enynes in satisfactory to excellent yields. The mechanism study reveals that the cross-dimerization of internal alkynes generated in situ with terminal alkynes proceeds via allene intermediates. The directing group 8-aminoquinoline plays a key role in the current selective synthesis of (E)-1,3-enynes.

Effects of medial support screws on locking plating of proximal humerus fractures in elderly patients: a retrospective study.

BACKGROUND: This study aimed to explore the effects of medial support screws (MSS) on the locking proximal humeral plate in elderly patients who suffered from proximal humeral fractures. METHODS: From December 2016 to December 2018, eighty-five elderly patients who suffered from proximal humeral fracture and received standard plate or locking plate with or without MSS were selected. The patients were allocated into 3 groups: Standard plate group (n=23), Locking plate without MSS group (n=34) and Locking plate with MSS group (n=28). Clinical data from all these 3 groups were collected and analyzed. RESULTS: These eighty-five elder patients (ranging 60-78 years) accomplished a follow-up with an average of 16.3 months. The outcome data showed that significant difference was found on the Constant score, humeral internal rotation angle and humeral height ratio (all the P<0.05) among 3 groups, and a highest Constant score and a lowest humeral internal rotation angle and humeral height ratio loss was revealed in Locking platelet with MSS group. Furthermore, the lowest incidence of post-operation complication events (7.1%, P=0.051) and an evident reduction of secondary surgery incidence (P=0.021) was also presented in Locking plate with MSS among these 3 groups. CONCLUSIONS: The medial support screws in the locking proximal humeral plate in treating proximal humeral fractures could reduce humerus restoration loss and humeral internal rotation angle.

[Expression of B-cell lymphoma-2 protein multisite phosphorylation in autophagy after spinal cord injury in rats].

OBJECTIVE: To investigate the changes of autophagy after spinal cord injury (SCI) in rats and its relationship with multisite phosphorylation of B-cell lymphoma-2 (Bcl-2) protein. METHODS: Forty male Sprague-Dawley rats aged 8 weeks were used to prepare SCI models by modified Allen method, and the SCI model were prepared successfully in 36 rats. The 36 SCI models were randomly divided into SCI group, autophagy inhibitor group, and autophagy promoter group, with 12 rats in each group. Another 12 rats were selected as sham operation group with only laminectomy and no spinal cord injury. At the end of modeling, the autophagy inhibitor group and the autophagy promoter group were intrathecally injected with 20 µL of 600 nmol/L 3-methyladenine and 25 nmol/L rapamycin, respectively, once a day for 4 weeks. The sham operation group and the SCI group were injected with only 20 µL of normal saline at the same time point. The motor function of rat in each group was evaluated by the Basso-Beattie-Bresnahan (BBB) score at 1 day and 1, 2, 4 weeks after modeling. The rats in each group were sacrificed at 24 hours after the last injection and the spinal cord tissues were taken. ELISA assay was used to detect the levels of inflammatory factors in spinal cord tissues, including myeloperoxidase (MPO), tumor necrosis factor α (TNF-α), and interleukin 1ß (IL-1ß); the morphological changes of spinal cord were observed by HE staining; the autophagy of mitochondria in spinal cord tissues was observed by transmission electron microscopy; the expressions of Beclin1 and microtubule-associated protein light chain 3 (LC3) were detected by immunofluorescence staining; neuronal apoptosis in spinal cord tissues were observed by TUNEL staining; LC3/TUNEL positive cells were calculated by immunofluorescence double staining; the expressions of Bcl-2 associated X protein (Bax), Bcl-2, p-Bcl-2 (Ser87), and p-Bcl-2 (Ser70) were detected by Western blot. RESULTS: Compared with sham operation group, BBB score of SCI group decreased at each time point, while the levels of MPO, TNF-α, and IL-1ß increased; peripheral space of nerve cells enlarged, cells swelled, vacuoles appeared, and autophagic bodies appeared in mitochondria; the positive rates of Beclin1 and LC3 proteins, and apoptotic rate of neurons significantly increased; the LC3/TUNEL positive cells significantly increased; the expressions of Bax, p-Bcl-2 (Ser87), and p-Bcl-2 (Ser70) proteins increased, while the expression of Bcl-2 protein decreased; all showing significant differences ( P<0.05). Compared with SCI group, BBB score in autophagy inhibitor group decreased at each time point, while the levels of MPO, TNF-α, and IL-1ß increased; a few autophagic vesicles appeared in mitochondria; the positive rates of Beclin1 and LC3 proteins decreased and the apoptotic rate of neurons increased significantly; the LC3 positive cells decreased and the TUNEL positive cells increased; the expressions of Bax, p-Bcl-2 (Ser87), and p-Bcl-2 (Ser70) proteins increased, while the expression of Bcl-2 protein decreased. The results of autophagy promoter group were opposite to those of autophagy inhibitor group; all showing significant differences between groups ( P<0.05). CONCLUSION: Induction of autophagy after SCI in rats can reduce neuronal apoptosis and protect spinal cord function, which may be related to the inhibition of Bcl-2 protein multisite phosphorylation.

Treatment of Soft Tissue and Bony Spinal Stenosis by a Visualized Endoscopic Transforaminal Technique Under Local Anesthesia.

OBJECTIVE: To analyze long-term clinical outcomes of endoscopic transforaminal foraminoplasty for foraminal stenosis. METHODS: Long-term 5-year MacNab outcomes, visual analogue scale (VAS) scores, complications, and unintended aftercare were analyzed in a series of 86 patients who underwent endoscopic transforaminal foraminoplasty for foraminal stenosis. RESULTS: At minimum 5-year follow-up, excellent results according to the MacNab criteria were obtained in 32 patients (37.2%), Good in 40 (46.5%), fair in 11 (12.8%), and poor in 3 (3.5%), respectively. The mean preoperative VAS was 6.15. The mean postoperative and last follow-up VAS was 3.44. Both postoperative VAS and last follow-up VAS were statistically reduced at a significance level of p<0.0001. Postoperative dysesthesia occurred in 9 patients. Another 9 patients had recurrent disc herniations (10.5%). Failure to cure with persistent pain occurred in 3 patients. Two patients developed pain postoperatively stemming from a different level. One patient experienced a postoperative hematoma which ultimately was inconsequential and did not require any additional surgery. Only 3 patients opted for revision endoscopic discectomy and another 2 for revision fusion surgery. CONCLUSION: Patients with symptomatic foraminal stenosis may be treated successfully with early transforaminal endoscopic decompression while maintaining favorable long-term outcomes without the need for fusion in the vast majority of patients.

[The role and mechanism of S100 calcium binding protein B in osteoarthritis cartilage damage repair].

Objective: To investigate the role and mechanism of S100 calcium binding protein B (S100B) in osteoarthritis (OA) cartilage damage repair. Methods: Twenty New Zealand rabbits were randomly divided into control group and model group, with 10 rabbits in each group. Rabbits in the model group were injured by the right knee joint immobilization method to make the artilage injury model, while the control group did not deal with any injury. After 4 weeks, the levels of interleukin-1ß (IL-1ß) and tumor necrosis factor α (TNF-α) in synovial fluid were detected by ELISA method; the mRNA and protein expressions of S100B, fibroblast growth factor 2 (FGF-2), and FGF receptor 1 (FGFR1) in cartilage tissue were examined by real-time fluorescence quantitative PCR (qRT-PCR) and Western blot assay. Human synovial fibroblasts (SF) were isolated and cultured in vitro. The effects of S100B overexpression and knockdown on the levels of IL-1ß and TNF-α (ELISA method) and the expressions of FGF-2 and FGFR1 gene (qRT-PCR) and protein (Western blot) were observed. Moreover, the effects of FGFR1 knockdown in above S100 overexpression system on the levels of IL-1ß and TNF-α (ELISA method) and the expressions of FGF-2 and FGFR1 gene (qRT-PCR) and protein (Western blot) were observed. Results: ELISA detection showed that the expressions of IL-1ß and TNF-α in the synovial fluid of the model group were significantly higher than those of the control group ( P<0.05); qRT-PCR and Western blot detection showed that the mRNA and protein expressions of S100B, FGF-2, and FGFR1 in cartilage tissue were significantly higher than those of the control group ( P<0.05). Overexpression and knockdown S100 could respectively significantly increase and decrease lipopolysaccharides (LPS) induced IL-1ß and TNF-α levels elevation and the mRNA and protein expressions of FGF-2 and FGFR1 ( P<0.05); whereas FGFR1 knockdown could significantly decrease LPS induced IL-1ß and TNF-α levels elevation and the mRNA and protein expressions of FGF-2 and FGFR1 ( P<0.05). Conclusion: S100B protein can regulate the inflammatory response of SF and may affect the repair of cartilage damage in OA, and the mechanism may be related to the activation of FGF-2/FGFR1 signaling pathway.

S100B regulates inflammatory response during osteoarthritis via fibroblast growth factor receptor 1 signaling.

The present study aimed to investigate the role of S100B in the inflammation process during osteoarthritis (OA). OA cartilage samples were collected for S100B expression analysis. S100B expression levels were significantly increased in patients with OA compared with the Controls (1.28±0.66 vs. 0.42±0.31; P=0.01) and were determined to be correlated with TNF­α (r=0.42; P=0.04) and IL­1ß (r=0.73; P=0.001) expression levels. Orthopedic casting tape was used to immobilize the right knee at 180˚ extension of adult female New Zealand white rabbits for 4 weeks to establish an OA model. Cartilage specimens from the medial femoral condyle of these rabbits were used for histological confirmation and immunohistochemical analyses, whereas synovial fluid was used in ELISA assays for tumor necrosis factor (TNF)­α and interleukin (IL)­1ß expression levels. Human synovial fibroblasts from the knee synovial tissues of normal patients with traumatic injury were transfected with S100B overexpression and knockdown plasmids and subjected to lipopolysaccharide (LPS) stimulation; subsequently, TNF­α and IL­1ß expression levels in conditioned medium were determined by ELISA; S100B overexpression and knockdown significantly increased and decreased the TNF­α and IL­1ß expression levels, respectively. Increased TNF­α (573.3±15.4 vs. 102.6±8.7 pg) and IL­1ß (378.6±7.2 vs. 170.1±5.8 pg) expression levels were detected in OA model rabbits compared with the Control rabbits. Additionally, S100B, fibroblast growth factor (FGF)­1 and FGF receptor (FGFR)­1 mRNA and protein expression levels were increased in OA model rabbits compared with the Control group. FGFR1 knockdown significantly decreased TNF­α and IL­1ß expression levels in LPS­stimulated S100B­overexpressing human synovial fibroblasts. S100B is involved in FGFR1 signaling­mediated inflammatory response during OA, which may be considered as a potential therapeutic target.

Clinical efficacy of meniscus plasty under arthroscopy in middle-aged and elderly patients with meniscus injury.

Clinical efficacy of meniscal plasty and total meniscectomy under arthroscopy in treating middle-aged and elderly patients with meniscus injury were explored. One hundred and fifteen elderly patients with meniscal injuries treated in the First Peoples Hospital of Wujiang District Suzhou from May 2012 to October 2014 were retrospectively analyzed. They were randomly divided into meniscal plasty group (experimental group) and total meniscectomy group (control group). Length of stay, operation time and VAS between the two groups were compared. Knee function was evaluated before the surgery and at the final follow-up using IKDC 2000 and Lysholm score. The differences of postoperative clinical efficacy and complications in both groups were observed. Postoperative IKDC 2000 and Lysholm score in the experimental group were superior to those of control group (P<0.001). There was no significant difference in the relieving effect of knee pain between the two types of procedures (P>0.05). Shorter operation time was found in control than that of experimental group. We did not observe remarkable differences in length of stay and postoperative complication rate between the two groups (P>0.05). Both meniscal plasty and total meniscectomy under arthroscopy can effectively relieve knee pain in a short time. Meniscal plasty could remarkably alleviate the progression of knee osteoarthritis, maintain knee function and improve daily life of affected population. We considered that meniscal plasty should be served as the preferred approach in treating middle-aged and elderly patients with meniscus injury.

Three-dimensional morphological analysis of acromioclavicular joint in patients with and without subacromial erosion after hook plate fixation.

Objective To investigate the role of acromioclavicular joint morphology in the presence of subacromial erosion after hook plate fixation. Methods We retrospectively analyzed the clinical data of 36 patients (17 men, 19 women; mean age, 48.7 years; range, 21-76 years) treated with hook plate fixation for distal clavicular fractures (n = 20) or acromioclavicular joint dislocation (n = 16) from August 2011 to March 2013. The patients were divided into two groups: the subacromial erosion group (18 patients) and the normal group (18 patients). Differences in multiple anatomical parameters between the two groups were measured and compared. Results The distal clavicle-acromion angle was significantly larger in the subacromial erosion group (mean, 51.37° ± 5.59°) than in the normal group (mean, 44.20° ± 3.83°), as was the distal clavicle-coronal angle (mean, 25.44° ± 2.51° vs. 21.67° ± 4.06°, respectively). The thickness of the acromion was significantly different between men and women (9.72 ± 1.13 vs. 8.16 ± 1.89 mm, respectively). Conclusion The results of this study indicate that the distal clavicle-acromion angle and distal clavicle-coronal angle are closely correlated with the occurrence of subacromial erosion after hook plate fixation.

Oxidized low density lipoprotein facilitates tumor necrosis factor­α mediated chondrocyte death via autophagy pathway.

We aimed to investigate the role of oxidized low density lipoprotein (ox­LDL) in tumor necrosis factor­α (TNF­α) mediated chondrocyte death and explore the mechanisms. Ten osteoarthritis (OA) and normal control cartilage tissue and synovial fluid (SF) samples were collected, and the expression of lectin­like ox­LDL receptor­1 (LOX­1) and ox­LDL level was examined by real time quantitative PCR and enzyme­linked immunosorbent assay (ELISA). An in vitro chondrocyte model was established by the introduction of TNF­α and ox­LDL, cell death was analyzed by trypan blue assay and the mechanisms were explored based on the apoptosis related pathway and autophagy pathway. Significantly increased ox­LDL level (70.30±17.83 vs. 37.22±19.97, P<0.05) in SF sample and LOX­1 expression level (0.51±0.10 vs. 0.32±0.04, P<0.05) in cartilage tissue was found in OA patients compared to those corresponding samples from control subjects. Ox­LDL could facilitate TNF­α mediated chondrocyte death and this effect could be blocked by LOX­1 antibody neutralization. Autophagy inhibition by 3­MA and Atg­5 siRNA could reverse the cell death effect mediated by TNF­α and ox­LDL co­treatment on chondrocytes. Oxidized low density lipoprotein facilitates tumor necrosis factor­α mediated chondrocyte death via its interaction with LOX­1, and autophagy is involved in the mechanisms.

[EXPRESSION AND ROLE OF KIP1 UBIQUITYLATION-PROMOTING COMPLEX 2 IN ASTROCYTES AFTER SPINAL CORD INJURY IN RATS].

OBJECTIVE: To explore the biological functions of Kip1 ubiquitylation-promoting complex 2 (KPC2) in the repair process of spinal cord injury (SCI) by studying the expression and cellular localization of KPC2 in rat SCI models. METHODS: Fifty-six adult Sprague-Dawley rats were randomly divided into 2 groups: in the control group (n = 7), simple T9 laminectomy was performed; in the experimental group (n = 49), the SCI model was established at T9, 7 rats were used to detect follow indexs at 6 hours, 12 hours, 1 day, 3 days, 5 days, 7 days, and 14 days after SC. Western blot analysis was used to detect the protein expressions of P27kip1, KPC2, CyclinA and proliferating cell nuclear antigen (PCNA) after SCI. Immunohistochemistry was used to observed the cellular localization of KPC2 after SCI, double-labeling immunofluorescence staining to observe the co-localization of KPC2 with neuronal nuclei (NeuN), glial fibrillary acidic protein (GFAP) and PCNA. In vitro astrocytes proliferation model was used to further validate these results, Western blot to detect KPC2, p27kip1, and PCNA expressions. The interaction of p27kip1, KPC1, and KPC2 in cell proliferation was analyzed by co-immunoprecipitation. RESULTS: The Western blot analysis showed a significant down-regulation of p27kip1 and a concomitant up-regulation of KPC2, CyclinA, and PCNA after SC. Immunohistochemistry staining revealed a wide distribution of KPC2 positive signals in the gray matter and white matter of the spinal cord. The number of KPC2 positive cells in the experimental group was significantly higher than that in the control group (t = 10.982, P = 0.000). Double-labeling immunofluorescence staining revealed the number of KPC2/NeuN co-expression cells in the gray matter of spinal cord was (0.43 ± 0.53)/visual field in the control group and (0.57 ± 0.53)/visual field in the experimental group, showing no significant difference (t = 0.548, P = 0.604); in the white matter of spinal cord, the number of KPC2/PCNA co-expression cells was (3.86 ± 0.90)/visual field in the control group and (0.71 ± 0.49)/visual field in the experimental group, showing significant difference (t = 7.778, P = 0.000). And then, the number of KPC2/PCNA co-expression cells were (0.57 ± 0.53)/visual field in the control group and (5.57 ± 1.13)/visual field in the experimental group, showing significant difference (t = 8.101, P = 0.000). Concomitantly, there was a similar kinetic in proliferating astrocytes in vitro. The Western blot analysis showed a significant down-regulation of p27kip1 and a concomitant up-regulation of KPC2 and PCNA after serum stimulated. Co-immunoprecipitation demonstrated increased interactions between p27kip1, KPC1, and KPC2 after stimulation. CONCLUSION: The up-regulated expression of KPC2 after SCI is related to the down-regulation of p27kip1, this event may be involved in the proliferation of astrocytes after SCI.

Biomechanical comparison of transforaminal lumbar interbody fusion with 1 or 2 cages by finite-element analysis.

BACKGROUND: Anterior lumbar interbody fusion and posterior lumbar interbody fusion with 1 cage have been shown to have similar biomechanics compared with the use of 2 cages. However, there have been no reports on the biomechanical differences between using 1 or 2 cages in transforaminal lumbar interbody fusion (TLIF) surgery. OBJECTIVE: To determine the biomechanical differences between the use of 1 or 2 cages in TLIF by finite-element analysis. METHODS: Three validated finite-element models of the L3-L5 lumbar segment were created (intact model and single- and paired-cage TLIF models). To study the biomechanics, a compressive preload of 400 N over 7.5 N-m was applied to the superior surfaces of the L3 vertebral body to simulate flexion, extension, rotation, and lateral bending. RESULTS: There was no significant difference in the range of motion between single-cage and paired-cage TLIF models, < 1° for all loading cases. Cage stress was high in the single-cage TLIF model under all loading conditions. Bone graft stress was high in the single-cage TLIF model. Pedicle screw stress was higher in the single-cage compared with the paired-cage TLIF. CONCLUSION: Single-cage TLIF approximates biomechanical stability and increases the stress of the bone graft. The use of a single cage may simplify the standard TLIF procedure, shorten operative times, decrease cost, and provide satisfactory clinical outcomes. Thus, single-cage TLIF is a useful alternative to traditional 2-cage TLIF.

Chitin nanowhisker aerogels.

Chitin nanowhiskers are structured into mesoporous aerogels by using the same benign process used previously in our group to make cellulose nanowhisker aerogels. The nanowhiskers are sonicated in water to form a hydrogel before solvent-exchange with ethanol and drying under supercritical CO2 (scCO2 ). Aerogels are prepared with various densities and porosities, relating directly to the initial chitin nanowhisker content. scCO2 drying enables the mesoporous network structure to be retained as well as allowing the gel to retain its initial dimensions. The chitin aerogels have low densities (0.043-0.113 g cm(-3) ), high porosities (up to 97 %), surface areas of up to 261 m(2) g(-1) , and mechanical properties at the high end of other reported values (modulus between 7 and 9.3 MPa). The aerogels were further characterized by using X-ray diffraction, BET analysis, electron microscopy, FTIR, and thermogravimetric analysis. Characterization showed that the rod-like crystalline nature of the nanowhiskers was retained during the aerogel production process, making the aerogel truly an assembled structure of chitin nanocrystals. These aerogels also showed the lowest reported shrinkage during drying to date, with an average shrinkage of only 4 %.

[Impact of joint capsule repair and external rotators suture on prognosis in primary total hip arthroplasty by posterolateral approach].

OBJECTIVE: To investigate the impact of joint capsule repair and external rotators suture on the prognosis in primary total hip arthroplasty (THA) by posterolateral approach. METHODS: Between January 2006 and June 2009, 159 patients with femoral neck fracture underwent primary THA by posterolateral approach, and were divided into 4 groups according to different treatments: joint capsule repair and external rotators suture were given in group A (n=38), only joint capsule repair in group B (n=39), only external rotators suture in group C (n=41), and no joint capsule repair or external rotators suture in group D (n=41). There was no significant difference in gender, age, cause of injure, disease duration, type of fracture, combined medical disease, or prosthesis selection among 4 groups (P > 0.05). The bleeding volume, drainage, postoperative hip dislocation rate, hip Harris score, and the hip range of motion (ROM) in internal rotation and external rotation were compared. RESULTS: There was no significant difference in operative time, bleeding volume, or drainage among 4 groups (P > 0.05). Postoperative hip dislocation occurred in 0, 0, 4 (9.8%), and 4 (9.8%) cases of groups A, B, C, and D, respectively, showing significant difference in incidence of postoperative hip dislocation among 4 groups (chi2=7.910, P=0.048). The hip Harris scores were significantly improved after operation when compared with preoperative scores in 4 groups (P < 0.05). Significant differences were found in hip Harris score at 6 weeks and 6 months after operation among 4 groups (P < 0.05); group D was significantly lower than groups A, B, and C, and groups B and C were significantly lower than group A (P < 0.05). There was no significant difference in the hip ROM in internal rotation among 4 groups at 6 weeks and 6, 12 months after operation (P > 0.05); but the hip ROM in external rotation were significantly bigger in groups A and C than in groups B and D at 6 weeks and 6 months after operation (P < 0.05). CONCLUSION: Joint capsule repair and external rotators suture in primary THA by posterolateral approach do not increase the bleeding volume and drainage, but can reduce the early postoperative hip dislocation risk, increase the Harris score, and recover the external rotation function of involved hip. So joint capsule and external rotators should be repaired in THA by posterolateral approach.

[Effectiveness comparison of micro-anchor repair and modified pull-out suture in treatment of mallet fingers].

OBJECTIVE: To compare the effectiveness between micro-anchor repair and modified pull-out suture in the treatment of mallet fingers. METHODS: Between June 2010 and March 2011, 33 patients with mallet fingers were treated by micro-anchor repair method (n = 18, group A) and by modified pull-out suture method in which the broken tendons were sutured with double metal needle Bunnell's suture and a knot was tied palmarly (n = 15, group B). There was no significant difference in age, gender, and disease duration between 2 groups (P > 0.05). RESULTS: The operation time was (62.5 +/- 3.1) minutes in group A and (65.0 +/- 4.6) minutes in group B, showing no significant difference (t = 1.85, P = 0.07). The treatment expense in group A [(8 566.2 +/- 135.0) yuan] was significantly higher than that in group B [(5 297.0 +/- 183.5) yuan] (t = 58.92, P = 0.00). Incision infection occurred in 2 cases of group A and 1 case of group B; the other patients obtained healing of incision by first intention. Relapsed mallet finger was observed in 1 case of group B. All patients in 2 groups were followed up 12-21 months. According to the Crawford functional assessment system, the results were excellent in 5 cases, good in 10 cases, fair in 2 cases, and poor in 1 case at the last follow-up with an excellent and good rate of 83.3% in group A; the results were excellent in 4 cases, good in 9 cases, fair in 1 case, and poor in 1 case with an excellent and good rate of 86.7% in group B. There was no significant difference in the excellent and good rate between 2 groups (chi 2 = 0.23, P = 0.97). CONCLUSION: Both micro-anchor repair and modified pull-out suture are simple and effective methods in the treatment of mallet finger. But compared with micro-anchor repair, pull-out suture has lower expense.

Expression of vascular endothelial growth factor and matrix metalloproteinase-9 in sacral chordoma.

Sacral chordoma is a vessel-rich and infiltrative tumor, but the fundamental knowledge of its biological behavior remains unknown. This study was designed to investigate the expression levels and contributions of vascular endothelial growth factor (VEGF) and matrix metalloproteinase-9 (MMP-9) in the angiogenesis and recurrence of sacral chordoma and their correlations. An immunohistochemical method was used to investigate the expression of VEGF, MMP-9, and microvascular density (MVD) in 36 patients with sacral chordoma. Their differences in expressions were statistically analyzed and their correlations with angiogenesis and recurrence were evaluated. The mean MVD of sacral chordomas was significantly higher than that of the adjacent normal tissues (P = 0.033). Immunoreactivity for VEGF and MMP-9 was significantly higher in sacral chordoma tissues than in adjacent normal tissues (P = 0.008, P = 0.005). The mean MVD of VEGF and MMP-9 were statistically higher in positive group than in negative group (P = 0.015, P = 0.004), respectively . Moreover, a significant correlation was found between the VEGF and MMP-9 (P = 0.002). The log-rank test revealed that continuous disease-free survival time (CDFS) was significantly shorter in the MMP-9-positive group than in the MMP-9-negative group (P = 0.019), but the difference in the VEGF-positive group and the VEGF-negative group was not statistically significant (P = 0.938). Our data suggest that VEGF and MMP-9 might act with a synergistic effect and can positively regulate the angiogenesis in sacral chordoma. Positive expression of MMP-9 might indicate the local recurrence of sacral chordoma. The result suggests that some specific drugs which inhibit VEGF, MMP-9, or their receptors may have a good therapeutic effect for sacral chordoma.

Surgical treatment of sacral chordomas combined with transcatheter arterial embolization.

STUDY DESIGN: A retrospective study, analyzing midterm results of transcatheter arterial embolization (TAE) for removal of a sacral chordoma. OBJECTIVE: To develop a suitable method to maximally remove the tumor. SUMMARY OF BACKGROUND DATA: Although previous reports have reported the use of TAE for removal of tumors, there is currently no data available on using this method to treat sacral chordomas. METHODS: Thirty patients with sacral chordomas, who underwent surgical treatment from January 1994 to September 2005, were selected. All 30 patients underwent the posterior approach after TAE of the main arteries that supplied the sacral chordoma. The average follow-up was 44.6 months after the operation. The blood lost during the operation, blood transfusion, and the blood drained from the patient after the operation was reviewed. In addition, the sphincter muscle function of the bladder and bowel was observed. RESULTS: The intraoperative blood loss averaged 1200 mL during the removal of the tumor. The average blood drained from the patient after the operation was 650 mL. The average blood transfusion postoperatively was 1080 mL. Of the 30 patients, 12 had recurrence and 2 died of tumor metastasis. In the 17 patients whose sacral nerve roots had been bilaterally reserved at and above the S3 level, the sphincter muscle function of the bladder and bowel was good, whereas the function of the sphincter muscles was impaired in 2 patients with nerve roots reserved only at and above the S1 level. In 1 case, colostomy and ureterocutaneosomy were used. CONCLUSIONS: In comparison with historical literature, preoperative TAE for excising the sacral tumor can significantly decrease intraoperative blood loss, make the surgical field clear, possibly eliminate the need for using an anterior approach, and facilitate the maximal removal of the sacral chordoma. It is an encouraging technique for excising the sacral chordomas.

Analysis of risk factors for recurrence after the resection of sacral chordoma combined with embolization.

BACKGROUND CONTEXT: Although several authors have already reported on the high local recurrence rate of sacral chordomas after surgical resection, there are no reports on the risk factors for recurrence after resection when combined with preoperative tumor-related blood vessel embolism by digital subtraction angiography (DSA) technique. PURPOSE: To investigate the factors related to the continuous disease-free survival time (CDFS) after the resection of sacral chordomas combined with embolization. STUDY DESIGN/SETTING: Retrospective review of the signs, images, and immunohistochemical data of patients with sacral chordomas treated with an initial operation combined with transcatheter arterial embolization. PATIENT SAMPLE: Twenty-two patients with sacral chordomas received initial resection combined with transcatheter arterial embolization. OUTCOME MEASURES: Recurrence, proliferating cell nuclear antigen (PCNA) expression, basic fibroblast growth factor (bFGF) expression, CDFS. METHODS: All cases were selected and followed for an average of 39.2 months. The roles of gender, age, tumor size, tumor location, surgical method, radiation therapy, PCNA expression, and bFGF expression in local recurrence were analyzed using the log-rank test. RESULTS: Sacral chordomas recurred in eight of 22 cases. The CDFS was significantly greater in tumors located below S3 as compared with those above S3. When evaluating PCNA and bFGF expression levels, the CDFS was greater in low expressions rather than high expressions. It was determined that the surgical method used was of prognostic significance to the CDFS. CONCLUSIONS: Higher tumor location and higher expressions of PCNA and bFGF will lead to a shorter CDFS. Resecting the tumor as completely as possible will decrease the chances of local recurrence of sacral chordomas.