Laboratory evidence of Weibel magnetogenesis driven by temperature gradient using three-dimensional synchronous proton radiography.

The origin of the cosmic magnetic field remains an unsolved mystery, relying not only on specific dynamo processes but also on the seed field to be amplified. Recently, the diffuse radio emission and Faraday rotation observations reveal that there has been a microgauss-level magnetic field in intracluster medium in the early universe, which places strong constraints on the strength of the initial field and implies the underlying kinetic effects; the commonly believed Biermann battery can only provide extremely weak seed of 10-21 G. Here, we present evidence for the spontaneous Weibel-type magnetogenesis in laser-produced weakly collisional plasma with the three-dimensional synchronous proton radiography, where the distribution anisotropy directly arises from the temperature gradient, even without the commonly considered interpenetrating plasmas or shear flows. This field can achieve sufficient strength and is sensitive to Coulomb collision. Our results demonstrate the importance of kinetics in magnetogenesis in weakly collisional astrophysical scenarios.

[Effectiveness analysis of medial buttress plate augmented hollow lag screws fixation in combination with sartorius pedicled iliac flap for the treatment of femoral neck fractures in young adults].

OBJECTIVE: To evaluate the effectiveness of medial buttress plate augmented hollow lag screws fixation in combination with sartorius pedicled iliac flap for the treatment of femoral neck fractures in young adults. METHODS: The clinical data of 11 young adult patients with femoral neck fractures between February 2013 and February 2019 were analyzed retrospectively. There were 7 males and 4 females with a mean age of 45 years (range, 32-58 years). Fractures were caused by falling from height in 6 cases, by traffic accident in 4 cases, and by sports injury in 1 case. There were 7 cases in the left hip and 4 cases in the right hip. The mean Pauwels angle was 64° (range, 55°-75°). All patients were treated by medial buttress plate augmented hollow lag screws fixation and sartorius pedicled iliac flap. The X-ray film of pelvis, lateral X-ray film of hip joint, CT scan and three-dimensional reconstruction of hip joint were taken after operation to assess fracture healing and position of the internal fixators. The postoperative hip function was evaluated according to the Harris score. RESULTS: All the incisions healed by first intention, and no complication such as incision infection and lateral femoral cutaneous nerve injury happened. Re-examination on the second day after operation showed that reduction and fixation of fractures was good. All patients were followed up 18-36 months (mean, 29 months). All fractures achieved bony union. The time of bony union was 16-23 weeks, with an average of 18.2 weeks. One patient (9.1%) got osteonecrosis of the femoral head (ONFH) at 30 months after operation. At last follow-up, Harris score was used to evaluate hip joint function, 9 cases were excellent, 1 case was good, 1 case was fair, and the excellent and good rate was 90.9%. CONCLUSION: Medial buttress plate augmented hollow lag screws fixation in combination with sartorius pedicled iliac flap for the treatment of femoral neck fractures in young adults has the advantage of strong biomechanical stability and can effectively improve the blood supply of femoral head and neck, which subsequently reduce the incidence of ONFH. However, the surgical indication should be fully considered.

Clinical outcomes of doubled-suture Nice knot augmented plate fixation in the treatment of comminuted midshaft clavicle fracture.

BACKGROUND: Free bone fragments were difficult to be fixed in many comminuted midshaft clavicle fractures, and the absence of cortical alignment in comminuted fractures had direct influence on the stability of fixation. This survey was performed to assess the efficacy of doubled-suture Nice knot augmented plate fixation in the treatment of comminuted midshaft clavicle fractures. METHODS: Between 2013 and 2018, all patients with comminuted midshaft clavicle fractures treated with doubled-suture Nice knot augmented plate fixation were retrospectively reviewed and included in this research. Demographic data of the patients, characteristics of the fractures, intraoperative parameters and follow-up data of the patients were evaluated and summarized. RESULTS: A total of 56 patients were included in this study. The mean follow-up time was 25.6 months (range, 12-60 months). The number of male patients was 38 (67.9 %) and of the female patients was 18 (32.1 %). The average age of all patients was 47.89 ± 16.5 years. The mean time of surgery was 85.6 ± 24.0 min. The average length of incision was 9.2 ± 1.9 cm. The number of doubled-suture Nice knot applied ranged from 1 to 5 knots. All the patients reached bone union after the treatment. There was no implant failure or neurovascular injury observed. And most of the patients showed good functional outcome. CONCLUSIONS: The doubled-suture Nice knot could provide reliable fixation for small bone fragments in comminuted clavicle fractures. Combination of the doubled-suture Nice knot and plate screws fixation was a safe and effective method in comminuted midshaft clavicle fractures treatment.

[Effectiveness of extended Carlson approach in treatment of lateral femoral condylar Hoffa fractures].

OBJECTIVE: To investigate the effectiveness of the extended Carlson approach in the treatment of lateral femoral condylar Hoffa fractures. METHODS: The clinical data of 17 patients with lateral femoral condyle Hoffa fractures between September 2012 and January 2019 were retrospectively analyzed. There were 10 males and 7 females, with a mean age of 43 years (range, 32-68 years). Fractures were caused by traffic accident in 9 cases, by falling from height in 6 cases, and by the other mechanism in 2 cases. According to the Letenneur's classification, there were 8 cases of typeⅠ, 6 cases of type Ⅱ, and 3 cases of type Ⅲ. The mean time from injury to operation was 7 days (range, 3-32 days). All patients were treated with extended Carlson approach. Patients with Letenneur types Ⅰ and Ⅲ were fixed by a posterior antigliding plate combined with headless compression screws from anteroposterior direction, and patients with Letenneur typeⅡ were fixed by headless compression screws from anteroposterior direction. The anteroposterior and lateral X-ray films, CT and three-dimensional reconstruction of the knee joint were taken after operation to assess fracture healing and position of the internal fixators. The knee function was evaluated according to Letenneur's functional assessment system. RESULTS: All patients were followed up 13-28 months (mean, 15 months). All the incisions healed by first intention, and no complication such as fracture redisplacement, fracture nonunion, internal fixator fracture, and common peroneal nerve injury occurred. The mean time of fracture healing was 18 weeks (range, 16-32 weeks). At last follow-up, according to Letenneur's functional assessment system, the knee function was excellent in 12 cases and good in 5 cases, with an excellent and good rate of 100%. CONCLUSION: The extended Carlson approach for the treatment of lateral femoral condylar Hoffa fractures has the advantages of clear exposure, easy reduction and fixation, high fracture healing rate, few complications, and good recovery of knee joint function.

Measurement of the sound velocity of shock compressed water.

The sound velocities of water in the Hugoniot states are investigated by laser shock compression of precompressed water in a diamond anvil cell. The obtained sound velocities in the off-Hugoniot region of liquid water at precompressed conditions are used to test the predictions of quantum molecular dynamics (QMD) simulations and the SESAME equation-of-state (EOS) library. It is found that the prediction of QMD simulations agrees with the experimental data while the prediction of SESAME EOS library underestimates the sound velocities probably due to its improper accounting for the ionization processes.

[The application of percutaneous retrograde pubic screw implantation assisted by hollow pedicle opener in treatment of pubic branch fracture].

OBJECTIVE: To evaluate the effectiveness of percutaneous retrograde pubic screw implantation assisted by hollow pedicle opener in pubic branch fractures. METHODS: The clinical data of 42 patients with pubic branch fractures treated by hollow screw fixation between March 2008 and March 2019 were analyzed retrospectively. According to the operation method, they were divided into the traditional operation group (20 cases in group A, fixed with traditional retrograde pubic screws) and the modified operation group (22 cases in group B, fixed with percutaneous retrograde pubic screws assisted by hollow pedicle opener). There was no significant difference ( P>0.05) between the two groups in terms of gender, age, cause of injury, fracture classification, comorbidity, and time from injury to operation. The operation time, blood loss, incision length, screw length, and complications were recorded and compared between the two groups. The fracture reduction was evaluated according to Matta standard on the next day after operation, and the function was evaluated by Majeed score at 12 months after operation. RESULTS: The operation was successfully completed in both groups. The operation time, blood loss, and incision length of group B were significantly less than those of group A ( P<0.05); there was no significant difference in screw length between the two groups ( t=0.793, P=0.437). All patients were followed up 8-24 months, with an average of 16.8 months. There was no complication in the two groups, such as injury of blood vessels and nerves, fracture of internal fixation, screw entering into joint cavity, and nonunion of fracture. There was no significant difference in the fracture healing time between the two groups ( t=-1.068, P=0.299). There were 2 cases of incision infection, 1 case of incision fat liquefaction, 2 cases of lower extremity deep vein thrombosis in group A, the incidence of complications was 25.0%; there was only 1 case of lower extremity deep vein thrombosis in group B, the incidence of complication was 4.5%, which was lower than that in group A, but the difference was not significant ( χ 2=2.104, P=0.147). In group A, 1 case was found to be dislocated, but in group B, there was no dislocated fracture. There was no significant difference between the two groups in the evaluation of Matta imaging on the next day after operation and the evaluation of Majeed function at 12 months after operation ( P>0.05). CONCLUSION: Percutaneous retrograde pubic screw implantation assisted by hollow pedicle opener is effect for the pubic branch fractures with the advantage of smaller incision, shorter operation time, and less bleeding compared with traditional methods.

[Effect of screw blade position on proximal femoral nail anti-rotation internal fixation for unstable intertrochanteric fractures in the elderly].

OBJECTIVE: To investigate the effect of the screw blade position on the effectiveness of proximal femoral nail anti-rotation (PFNA) internal fixation for unstable intertrochanteric fractures in the elderly. METHODS: A clinical data of 131 elderly patients with unstable intertrochanteric fractures who were treated with PFNA internal fixation between January 2010 and January 2017 was retrospectively analyzed. According to the anteroposterior X-ray films, the screw blades were placed in the middle of the femoral neck in 72 patients (group A) and at one-third of the femoral neck in 59 patients (group B). There was no significant difference between the two groups ( P>0.05) in the gender, age, bone density, classification of fractures, other medical diseases, and the time between injury and operation. Multiple treatment indexes were analyzed, including complications, hip Harris score, the healing status of fracture, tip-apex distance (TAD), and the height of the tail nail. RESULTS: All patients were followed up 11-14 months, with an average of 12.1 months. All incisions healed by first intention with no complications. All fractures healed and no significant difference in bone healing time between the two groups ( Z=-0.190, P=0.849). At 6 months after operation, TAD was (2.23±0.07) cm in group A and (2.85±0.12) cm in group B, showing significant difference ( t=-47.643, P=0.000); and the height of the tail nail was (1.72±0.14) cm in group A and (0.53±0.26) cm in group B, showing significant difference ( t=31.031, P=0.000). According to the Harris score, the hip functions were rated as excellent in 48 cases, good in 15 cases, and poor in 9 cases in group A, while as excellent in 38 cases, good in 16 cases, and poor in 5 cases in group B, with no significant difference between the two groups ( Z=-0.075, P=0.941). CONCLUSION: For the unstable intertrochanteric fracture in the elderly, the PFNA internal fixation with appropriated TAD and the screw blades placed in the middle or at one-third of the femoral neck can obtain good effectiveness.

Adjacent two-level anterior cervical discectomy and fusion versus one-level corpectomy and fusion in cervical spondylotic myelopathy: Analysis of perioperative parameters and sagittal balance.

OBJECTIVES: The optimal surgical strategy for cervical spondylotic myelopathy (CSM) remains controversial; thus, the current study was designed to compare the outcomes of two different anterior approach surgeries for two-level CSM, namely, adjacent two-level anterior cervical discectomy and fusion (ACDF) and one-level anterior cervical corpectomy and fusion (ACCF). PATIENTS AND METHODS: A total of 53 patients who underwent adjacent two-level ACDF and 68 patients who underwent one-level ACCF in the Spinal Surgery Department from January 2010 to October 2017 were retrospectively analyzed. Independent sample t tests and chi-square tests were used to compare perioperative parameters (hospital stays, bleeding amounts and operation times), clinical parameters (Neck Disability Index scores and Visual Analog Scale scores for neck and arm pain), and radiologic parameters (difference in segmental height, T1 slope, C2-7 sagittal vertical axis, C2-7 lordosis, segmental angle, and fusion rate). RESULTS: The length of hospital stay (p < 0.01), bleeding amount (p < 0.01), operation time (p < 0.001) and difference in segmental height (p < 0.001) were significantly greater in the ACCF group than in the ACDF group, whereas C2-7 lordosis (p < 0.05) and the segmental angle (p < 0.001) were significantly lower in the ACCF group than in the ACDF group. Other parameters were not significantly different between the two groups. CONCLUSION: Both ACDF and ACCF provided satisfactory clinical outcomes and fusion rates for CSM. However, adjacent two-level ACDF was associated with shorter hospital stays, less blood loss, shorter operative times, fewer differences in segmental height and greater improvement in segmental lordotic curvature. On most occasions, when either surgical method could be selected, adjacent two-level ACDF as a surgical treatment for CSM may be a worthwhile alternative method to one-level ACCF.

Adsorption of Cu(II) by phosphogypsum modified with sodium dodecyl benzene sulfonate.

Phosphogypsum (PG) is a solid waste generated during the wet production of phosphoric acid, and stockpiling PG causes serious pollution to the environment. Therefore, we prepared an adsorption material modified with sodium dodecyl benzene sulfonate (SDBS) based on PG (SDBS@PG). SDBS@PG can be regenerated and used in several adsorption-desorption cycles. The optimum conditions for Cu(II) removal are as follows: the Cu(II) concentration is 10 mg/L, the amount of adsorbent is 1.6 g/L, the pH is 6, and the contact time is 60 min. Under these conditions, the removal rate is 99.23 %. The kinetic data of adsorption conform to the pseudo-second-order model. The equilibrium isotherm results are consistent with the Langmuir isotherm equation. Furthermore, plausible mechanisms were proposed: PG was modified with SDBS, which greatly improved the adsorption of Cu(II) onto PG. The main reason is that SDBS is adsorbed on the surface of PG by chemical action in the form of micelles and then Cu(II) is adsorbed on the anionic SDBS micelles of SDBS@PG due to chemical and electrostatic interactions. This work indicates that SDBS@PG can be used for the removal of Cu(II) and is qualified for practical application.

The modified anterior ellipsoidal cap titanium cable tension band for comminuted patellar fractures.

PURPOSE: The purpose of this study was to assess the outcomes in a series of patients, who underwent cerclage and figure-of-eight tension band wiring using a single titanium cable for comminuted patellar fractures. METHODS: We describe a modified tension band technique using a single titanium cable to create an ellipsoidal cap structure that combines the circumferential and figure-of-eight wrapping in the fixation of closed Association for the Study of Internal Fixation/Orthopaedic Trauma Association 34C2 and 34C3 patellar fractures. We retrospectively reviewed 25 patients (16 males and 9 females, mean age 54 years) who underwent the described fixation technique between 2015 and 2017. Postoperative function was evaluated using the Böstman score. RESULTS: At the mean follow-up of 25 months (range 17-39 months), the mean Böstman score was 27.3 ± 2.6 points (range 23-30). Eighteen patients (72%) had excellent results (score ≥28); seven patients (28%) had good results (score 20-27); and no patients had an unsatisfactory result (score < 20). All surgical incisions healed without major wound complications. Two patients reported minor complications (soft tissue irritation, cellulitis). No patients demonstrated loss of reduction or implant failure during the follow-up period. CONCLUSION: The modified anterior ellipsoidal cap tension band using a single titanium cable created an effective tension band structure in the treatment of comminuted patella fractures. It is a simple operative technique that produced a stable fixation construct, which allowed early functional rehabilitation and weight-bearing with a high rate of excellent outcomes at 2 years after surgery.

[Effectiveness analysis of distal radius microplate locking plate for treatment of displaced fracture of medial clavicle].

OBJECTIVE: To investigate and evaluate the effectiveness of the distal radius microplate locking plate for the treatment of displaced fracture of medial clavicle. METHODS: Between January 2013 and June 2017, 18 cases of obvious displaced fracture of medial clavicle were treated with distal radius microlocking plate. There were 10 males and 8 females, with an average age of 51.4 years (range, 18-88 years). Causes of injury included traffic accident injury in 15 cases, heavy object injury in 3 cases; all of them were closed injury. According to Edinburgh classification, 15 cases were ⅠB1 type and 3 cases were ⅠB2 type. Fracture displacement was 12-21 mm (mean, 16.3 mm). The time from injury to operation was 3-7 days (mean, 4.3 days). After operation, the clinical healing and complications of fracture were observed, and shoulder function was evaluated according to Rockwood's scoring criteria. RESULTS: No incisional infection, neurovascular injury, or other early complications occurred. All 18 patients were followed up 8-15 months (mean, 12 months). All fractures reached clinical osseous union, and the healing time was 8-24 weeks (mean, 16.6 weeks). Postoperative plate loosening occurred in 1 case, which was removed surgically, while other patients did not suffer from complications such as bone nonunion, displacement, internal fixator loosening, and loss of reduction. At last follow-up, according to Rockwood's scoring criteria, the results were excellent in 12 cases and good in 6 cases. CONCLUSION: The distal radius microplate locking plate is effective for the treatment of displaced medial clavicle fracture, which has few complications, and is feasible for early functional exercise, and is helpful for the recovery of shoulder joint function.

Metformin alleviates hyperglycemia-induced apoptosis and differentiation suppression in osteoblasts through inhibiting the TLR4 signaling pathway.

AIMS: Metformin was found to protect against hyperglycemia-induced injury in osteoblasts, but the cellular mechanisms involved remain unclear. Therefore, the aim of this study was to determine the effect of metformin on hyperglycemia-induced apoptosis and differentiation suppression in osteoblasts and to explore its relationships with the TLR4 signaling pathway. MAIN METHODS: A mouse osteoblast cell line, MC3T3-E1, and a diabetic rat model were used to survey the protective effects of metformin on hyperglycemia-induced injury. TLR4 expression was altered using small interfering (si)RNA and lentivirus-mediated TLR4 overexpression. LPS was used as a specific TLR4 activator, and CLI-095 was used as a TLR4 inhibitor. KEY FINDINGS: Metformin improved osteoblast differentiation, reduced apoptosis in hyperglycemic osteoblasts, and inhibited TLR4, MyD88 and NF-κB expression in a dose-dependent manner. Down-regulating the expression or inhibiting the activity of TLR4 enhanced these protective effects of metformin on osteoblast differentiation, cell viability and cell apoptosis in hyperglycemic conditions, whereas up-regulating the expression or activating the activity of TLR4 had the opposite effects. Activating NF-κB suppressed the protective effects of metformin, while inhibiting NF-κB activity had the opposite effects. Metformin increased ALP and OCN secretion, enhanced BMP-2 expression, improved bone mineral density (BMD), and decreased TLR4, MyD88 and NF-κB levels in the femur tissues of diabetic rats. SIGNIFICANCE: Taken together our experimentation support the hypothesis that metformin may alleviate hyperglycemia-induced apoptosis and differentiation suppression in osteoblasts by inhibiting the TLR4/MyD88/NF-κB signaling pathway.

[Effectiveness of cerclage and a figure-of-eight tension band by a single titanium wire in treatment of patellar fracture].

Objective: To estimate the outcome of cerclage followed by a figure-of-eight tension band with a single titanium wire for the treatment of patellar fracture. Methods: A retrospective analysis was made on the clinical data of 46 patients with patellar fractures treated between June 2012 and November 2014. There were 30 males and 16 females, aged 20-86 years (mean, 54 years). The fracture causes included falling in 27 cases, traffic accident in 16 cases, and knock in 3 cases. There were 41 cases of closed fractures and 5 cases of open fracture. The injury located at the left side in 24 cases and the right side in 22 cases. According to AO classification, fracture was rated as type 34-A in 3 cases, as type 34-B in 1 case, as type 34-C1 in 7 cases, as type 34-C2 in 13 cases, and as type 34-C3 in 22 cases. The time between injury and operation ranged 1-12 days (mean, 3.7 days). During operations, a single titanium wire was used to pass around the patellar, followed a figure-of-eight wrapping, to tight and fix at the tension of 35 kg. Results: All incisions healed primarily. The patients were followed up 20.6 months on average (range, 6-24 months). Partial wire loosening was found in 2 cases, irritation of skin or soft tissue in 1 case. The X-ray examination showed bony healing at 3 months after operation, without breakage of titanium wire. The internal fixation was removed in 38 cases at 12 months after operation. According to the Böstman rating score, the mean score was 28.34 (range, 24-30) at 12 months after ope-ration; the results were excellent in 42 cases and good in 4 cases, with an excellent and good rate of 100%. Conclusion: For patellar fracture, cerclage followed by a figure-of-eight tension band with a single titanium wire is able to achieve an effective stability and to allow early motion for patient with less complication.

Role of IL-17 in nucleus pulposus cell proliferation and metabolism cultured in vitro.

OBJECTIVE: To explore the role of cytokine, interleukin-17 (IL-17) in human degenerative disc disease. METHODS: Through magnetic resonance imaging, human degenerative disc tissues were confirmed from the isolated nucleus pulposus cells, which were then cultured in vitro. The cells were cultured with and without different concentrations of IL-17. 2 ng/mL, 5 ng/mL, 10 ng/mL, 15 ng/mL and 20 ng/mL IL-17 concentrations were used for stimulation. After 72 hours, the inhibition rate of proliferation was measured by MTS method. For 48 and 96 hours, the nucleus pulposus cells were cultured with and without the appropriate IL-17 concentrations. The mRNA and protein expression levels of the matrix macromolecules and degrading tissue genes were measured by Real-time PCR and Western blot analysis. RESULTS: It was noted that nucleus pulposus cell proliferation was inhibited after culturing in vitro with IL-17 stimulation, and it was further observed that the inhibition effect was significantly stronger with 15 ng/mL IL-17 concentration. With the dosage of 15 ng/mL, IL-17 stimulation induced multiple cellular responses, such as the significant increase in mRNA expression for both aggrecan (ACAN) and type I collagen (COLLA1) genes (P<0.05), and the significant decrease in mRNA expression of both degrading tissue genes, MMP3 and TIMP3 (P<0.05). Western blot results also showed that the protein level of COL1A1 was significantly decreased (t=3.199, P=0.006), while the protein level of one peptidases (ADAMTS5) significantly increased (t=2.667, P=0.021). CONCLUSIONS: These findings suggest that IL-17 can inhibit proliferation and affect the metabolism of the cultured nucleus pulposus cells in vitro, and these findings could possibly contribute to the degenerative changes that occur in DDD through extracellular matrix synthesis inhibition, promoting nucleus pulposus extracellular matrix degradation and disrupting the metabolic balance.

[Clinical application of radial mid-forearm perforator fasciocutaneous flap].

OBJECTIVE: To investigate the effectiveness of using radial mid-forearm perforator fasciocutaneous flap to repair soft tissue defect in lower segment of the forearm and the wrist. METHODS: Between May 2007 and July 2012, 7 cases of soft tissue defect of lower segment of the forearm and the wrist were repaired with radial mid-forearm perforator fasciocutaneous flap. There were 6 males and 1 female with an average age of 38 years (range, 22-45 years). Defects were caused by crushing injury in 4 cases with the disease duration of 3-22 days (mean, 14 days), by internal fixation of ulnar comminuted fracture in 2 cases after 16 and 20 days of operation respectively, and by focal cleaning of wrist joint tuberculosis in 1 cases after 24 days of operation. The locations of defect were the lower segment of the forearm in 5 cases and the dorsal side of the wrist in 2 cases. The area of soft tissue defect ranged from 4 cm x 3 cm to 9 cm x 5 cm. The size of flap ranged from 6 cm x 4 cm to 12 cm x 6 cm. The donor site was closed with direct suturing or skin grafting. RESULTS: The intraoperative blood loss was 50- 90 mL (mean, 64 mL); the operation time was 60-80 minutes (mean, 72 minutes). Six flaps survived with wound healing by first intention; partial flap necrosis occurred in 1 case, and delayed healing was obtained after dressing change. Skin grafting at donor sites survived with healing of incision bly first intention. The patients were followed up 3-14 months (mean, 9 months). No ulcer or sinus tract was observed; all flaps showed a slightly swollen appearance and had normal color. CONCLUSION: Radial mid-forearm perforator fasciocutaneous flap does not need to dissect the source of blood vessels due to constantly anatomical structure. It has the advantages of easy operation, rich blood supply, high survival rate, and satisfactory clinical effect, so it is an important supplement of the other non-main vessel pedicle flaps to repair soft tissue defect in the lower segment of the forearm and the wrist.

[Time differences of bone marrow mesenchymal stem cells and nucleus pulposus-like cells in a non contact co-culture system].

OBJECTIVE: To investigate time differences in directional differentiation of bone marrow mesenchymal stem cells (BMSCs) into nucleus pulposus-like cells (NPCs) in a non contact co-culture system so as to search for the best time for transplantation in vivo. METHODS: Six New Zealand white rabbits (aged 6 weeks, weighing 1.5-2.0 kg) were selected. BMSCs were collected and cultured for immunocytochemistry identification of CD34, CD44, CD45, and CD90; NPCs were isolated and identified immunocytochemically by RT-PCR. The 2nd passage BMSCs and the primary NPCs were co-cultured in a non contact co-culture system. The cell morphological changes were observed and the cell growth curves were made at 1, 3, and 5 passages after co-culture. The expressions of the aggrecan and collagen type II genes were detected by RT-PCR in BMSCs at 5, 10, and 15 days after co-culture; the expressions of the aggrecan and collagen type II proteins were detected by Western blot at 5, 10, 15, 20, 25, and 30 days after co-culture. RESULTS: The expressions of CD44 and CD90 were positive, CD34 and CD45 were negative in BMSCs. The expressions of the collagen type II and aggrecan were positive in NPCs. At 2 weeks after co-culture, the morphology of BMSCs changed obviously, the cells were polygonal and irregular shape. The cell growth rate showed no difference within 3 passages, but decreased obviously after 3 passages. RT-PCR showed that the expressions of collagen type II and aggrecan genes at 10 and 15 days were significantly higher than those at 5 days (P < 0.05), no significant difference was found between at 10 days and at 15 days (P > 0.05). Western blot showed that the expressions of collagen type II and aggrecan proteins gradually increased with time, and there was significant difference within 5, 10, and 15 days (P < 0.05), but no significant difference was found after 15 days of co-culture (P > 0.05). CONCLUSION: In a non contact co-culture system, BMSCs can differentiate into the NPCs. The expression of collagen type II and aggrecan can reach a stable level at 15 days after co-culture, and it is the suitable time for transplantation in vivo.

[Comparison of three methods for the treatment of aged femoral intertrochanteric fracture].

OBJECTIVE: To investigate the reasonable methods of treatment for aged intertrochanteric fractures through the comparison and analysis about the clinical data and follow-up results of three kinds of treatment method of elderly intertrochanteric fractures. METHODS: From June 2004 to June 2010,131 patients with intertrochanteric fractures were treated and reviewed retrospectively. Among them, 72 patients were treated with dynamic hip screw (DHS) included 20 males and 52 females with an average age of (72.5 +/- 5.5) years, 43 patients were treated with proximal femoral nail antirotation (PFNA) included 12 males and 31 females with an average age of (72.8 +/- 4.9) years and 16 patients were treated with hemiarthroplasty included 4 males and 12 females with an average age of (76.0 +/- 5.0) years. The three groups of patients were statistically analyzed and compared on surgical trauma including operation time, blood loss, incision length, X-ray exposure, and on postoperative recovery including non-weight-bearing walking time, the hospitalization time, the healing time, the recovery of joint function and complications. RESULTS: All patients were followed-up from 6 months to 3 years (means 18.2 months). In surgical trauma: the results of length of incision,operation time and blood loss was DHS>hemiarthroplasty>PFNA. PFNA group had the most X-ray exposure, hemiarthroplasty group had the least. In postoperative recovery: the results of in non-weight-bearing walking time, hospitalization time and healing time was DHS>PFNA>hemiarthroplasty. Harris scores at 12 weeks after operation in hemiarthroplasty was higher than that of DHS and PFNA, but there was no statistical difference between DHS and PFNA. The incidence of postoperative complications in DHS group was more than that of PFNA group, but there were not significant differences among three groups. CONCLUSION: PFNA is prepered in the treatment of senile intertrochanteric fractures. DHS fixation is more suitable for primary hospital and AI-type fracture and the fracture near the entry point of PFNA. The hemiarthroplasty is one of the best ways to treat unstable comminuted and/or severe osteoporosis of elderly intertrochanteric fracture. However,it isn't generally considered.