One-stage human acellular nerve allograft reconstruction for digital nerve defects

Human acellular nerve allografts have a wide range of donor origin and can effectively avoid nerve injury in the donor area. Very little is known about one-stage reconstruction of digital nerve defects. The present study observed the feasibility and effectiveness of human acellular nerve allograft in the reconstruction of < 5-cm digital nerve defects within 6 hours after injury. A total of 15 cases of nerve injury, combined with nerve defects in 18 digits from the Department of Emergency were enrolled in this study. After debridement, digital nerves were reconstructed using human acellular nerve allografts. The patients were followed up for 6–24 months after reconstruction. Mackinnon-Dellon static two-point discrimination results showed excellent and good rates of 89%. Semmes-Weinstein monofilament test demonstrated that light touch was normal, with an obvious improvement rate of 78%. These findings confirmed that human acellular nerve allograft for one-stage reconstruction of digital nerve defect after hand injury is feasible, which provides a novel trend for peripheral nerve reconstruction.

Electrical stimulation does not enhance nerve regeneration if delayed after sciatic nerve injury: the role of fibrosis

Electrical stimulation has been shown to accelerate and enhance nerve regeneration in sensory and motor neurons after injury, but there is little evidence that focuses on the varying degrees of fibrosis in the delayed repair of peripheral nerve tissue. In this study, a rat model of sciatic nerve transection injury was repaired with a biodegradable conduit at 1 day, 1 week, 1 month and 2 months after injury, when the rats were divided into two subgroups. In the experimental group, rats were treated with electrical stimuli of frequency of 20 Hz, pulse width 100 ms and direct current voltage of 3 V; while rats in the control group received no electrical stimulation after the conduit operation. Histological results showed that stained collagen fibers comprised less than 20% of the total operated area in the two groups after delayed repair at both 1 day and 1 week but after longer delays, the collagen fiber area increased with the time after injury. Immunohistochemical staining revealed that the expression level of transforming growth factor β (an indicator of tissue fibrosis) decreased at both 1 day and 1 week after delayed repair but increased at both 1 and 2 months after delayed repair. These findings indicate that if the biodegradable conduit repair combined with electrical stimulation is delayed, it results in a poor outcome following sciatic nerve injury. One month after injury, tissue degeneration and distal fibrosis are apparent and are probably the main reason why electrical stimulation fails to promote nerve regeneration after delayed repair.

Local administration of icariin contributes to peripheral nerve regeneration and functional recovery

Our previous study showed that systemic administration of the traditional Chinese medicine Epimedium extract promotes peripheral nerve regeneration. Here, we sought to explore the therapeutic effects of local administration of icariin, a major component of Epimedium extract, on peripheral nerve regeneration. A poly(lactic-co-glycolic acid) biological conduit sleeve was used to bridge a 5 mm right sciatic nerve defect in rats, and physiological saline, nerve growth factor, icariin suspension, or nerve growth factor-releasing microsphere suspension was injected into the defect. Twelve weeks later, sciatic nerve conduction velocity and the number of myelinated fibers were notably greater in the rats treated with icariin suspension or nerve growth factor-releasing microspheres than those that had received nerve growth factor or physiological saline. The effects of icariin suspension were similar to those of nerve growth factor-releasing microspheres. These data suggest that icariin acts as a nerve growth factor-releasing agent, and indicate that local application of icariin after spinal injury can promote peripheral nerve regeneration.

Dorsal root ganglion neurons promote proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells

Preliminary animal experiments have confirmed that sensory nerve fibers promote osteoblast differentiation, but motor nerve fibers have no promotion effect. Whether sensory neurons promote the proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells remains unclear. No results at the cellular level have been reported. In this study, dorsal root ganglion neurons (sensory neurons) from Sprague-Dawley fetal rats were co-cultured with bone marrow mesenchymal stem cells transfected with green fluorescent protein 3 weeks after osteogenic differentiation in vitro, while osteoblasts derived from bone marrow mesenchymal stem cells served as the control group. The rat dorsal root ganglion neurons promoted the proliferation of bone marrow mesenchymal stem cell-derived osteoblasts at 3 and 5 days of co-culture, as observed by fluorescence microscopy. The levels of mRNAs for osteogenic differentiation-related factors (including alkaline phosphatase, osteocalcin, osteopontin and bone morphogenetic protein 2) in the co-culture group were higher than those in the control group, as detected by real-time quantitative PCR. Our findings indicate that dorsal root ganglion neurons promote the proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells, which provides a theoretical basis for in vitro experiments aimed at constructing tissue-engineered bone.

Large animal models of human cauda equina injury and repair: evaluation of a novel goat model

Previous animal studies of cauda equina injury have primarily used rat models, which display significant differences from humans. Furthermore, most studies have focused on electrophysiological examination. To better mimic the outcome after surgical repair of cauda equina injury, a novel animal model was established in the goat. Electrophysiological, histological and magnetic resonance imaging methods were used to evaluate the morphological and functional outcome after cauda equina injury and end-to-end suture. Our results demonstrate successful establishment of the goat experimental model of cauda equina injury. This novel model can provide detailed information on the nerve regenerative process following surgical repair of cauda equina injury.

Biodegradable chitin conduit tubulation combined with bone marrow mesenchymal stem cell transplantation for treatment of spinal cord injury by reducing glial scar and cavity formation

We examined the restorative effect of modified biodegradable chitin conduits in combination with bone marrow mesenchymal stem cell transplantation after right spinal cord hemisection injury. Immunohistochemical staining revealed that biological conduit sleeve bridging reduced glial scar formation and spinal muscular atrophy after spinal cord hemisection. Bone marrow mesenchymal stem cells survived and proliferated after transplantation in vivo, and differentiated into cells double-positive for S100 (Schwann cell marker) and glial fibrillary acidic protein (glial cell marker) at 8 weeks. Retrograde tracing showed that more nerve fibers had grown through the injured spinal cord at 14 weeks after combination therapy than either treatment alone. Our findings indicate that a biological conduit combined with bone marrow mesenchymal stem cell transplantation effectively prevented scar formation and provided a favorable local microenvironment for the proliferation, migration and differentiation of bone marrow mesenchymal stem cells in the spinal cord, thus promoting restoration following spinal cord hemisection injury.

[Case-control study on effects of fracture of processus styloideus ulnae on prognosis after plate fixation for the treatment of distal radial fractures]

OBJECTIVE

To analyze effects of fracture of processus styloideus ulnae on prognosis in the treatment of distal radial fracture of type C according to AO classification.

METHODS

This was a retrospective case-control study, and the information was got ten through case evaluation and follow-up, including sex, age, patient satisfaction, Gartland & Werley score and radiographic score. There were 76 patient treated with open reduction and plate fixation in People's Hospital Affiliated to Peking University from July 2006 to July 2011. All the patients were divided into two groups: no combination with fracture of processus styloideus ulnae (group A, 56 cases), combination with fracture of processus styloideus ulnae (group B, 20 cases). The patients in group A and B were treated with open reduction and internal fixation; however the fracture of processus styloideus ulnae was not fixed. The indexes such as clinical data, bone grafting, joint movement, Gartland & Werley score and radiographic score were compared between two groups.

RESULTS

The ulnaris pain of patients in group B was more obvious than that in group A. The local VAS, palmar and dorsal flexion degree of wrist joint, motion VAS, patients satisfaction score, radial and ulnar deviation degree, pronation and supination of forearm degree, Gartland & Werley score and radiographic score were separately 0.1 ± 0.1, (51.1 ± 1.9)°, (60.2 ± 1.9)°, 0.6 ± 0.1 (23.1 ± 0.9)°, (28.7 ± 1.3)° (81.5 ± 2.6)°, (68.2 ± 2.7)° 1.9 ± 0.3, 89.6 ± 12.3 in group A; and separately 0.3 ± 0.3, (51.4 ± 2.3)°, (66.6 ± 1.7)°, 0.5 ± 0.2, (24.5 ± 2.0)°, (26.9 ± 1.8)°, (80.3 ± 2.5)°, (70.3 ± 3.7)°, 1.2 ± 0.4, 92.5 ± 7.5 in group B; there were no statistical differences in above indexes between two groups.

CONCLUSION

Whether the distal radial fracture with a concomitant unrepaired ulnar styloid fracture or not exerts no influence on mainly outcomes including function, radiography and motion of the wrist.

Effect of active Notch signaling system on the early repair of rat sciatic nerve injury

It is all known that dedifferentiated Schwann cells (SCs) play an important role in neural regeneration, and Notch signaling has complex and extensive regulatory functions in dedifferentiated SCs. So studies have focused on how to improve peripheral nerve repair by regulating proliferation and dedifferentiation in SCs with Notch signaling meloculars.We have found SCs can be activated when adding Recombinant rat jagged1/FC chimera (an activator of the Notch signaling system) in vivo. Compared with that of the control groups, at 4 weeks post-surgery nerve regeneration and functional rehabilitation in the Recombinant rat jagged1/FC chimera group were advanced significantly, and the expression of neurotrophic factors in the regenerated nerves was elevated largely. These results indicated that SCs activated by Notch signaling could promote nerve repair effectively in the early regenerative stage, suggesting the possible clinical application for the treatment of peripheral nerve defects.

[Pain assessment of biological conduit small gap tubulization in rat sciatic nerve multilation model]

OBJECTIVE

To explore the pain sensation recovery discipline of 2 mm small gap biological conduit tubulization and epineurial neurorrhaphy in rat sciatic nerve multilation model.

METHODS

Based on the rat sciatic nerve multilation model, 2 mm small gap biological conduit tubulization and epineurial neurorrhaphy were applied and the 50% paw withdrawal threshold was observed after 2, 4, 5, 6, 8 and 12 weeks. The data were analyzed by two-way ANOVA and chi-square criterion.

RESULTS

Obvious hyperalgesia was observed in week 2 in both experimental group and control group, and 50% paw withdrawal threshold was improved significantly even to 15 g. The 50% paw withdrawal threshold began to decline week 4 and the 50% paw withdrawal threshold of small gap tubulization group was obviously lower than that of control group, which may imply that the pain sensation recovery of small gap tubulization group was earlier than that of control group. The 50% paw withdrawal threshold of small gap tubulization group began to increase to the plateau period [week 5: (12.70 ± 5.64) g; week 6: (12.20 ± 3.26) g; week 8: (12.31 ± 4.19) g; week 12: (13.95 ± 2.58) g]. The 50% paw withdrawal threshold of control group declined gradually [week 5: (10.47 ± 7.02) g; week 6: (9.42 ± 6.86) g; week 8: (8.50 ± 7.15) g; week 12: (8.06 ± 5.93) g]. The difference was statistical significant between small gap tubulization group and control group in 12th week.

CONCLUSION

Compared with the traditional epineurial neurorrhaphy for peripheral nerve multilation, 2 mm small gap biological conduit tubulization can improve the 50% paw withdrawal threshold during peripheral nerve regeneration process and reduce the pain incidence.

[Generation and characterization of peripheral nerve animal model of pure motor/sensory nerve fibers]

OBJECTIVE

To generate peripheral nerve animal model of pure motor nerve fibers/pure sensory nerve fibers, and identify them.

METHODS

The SPF SD rats were adopted in this study, and divided into 3 groups. In group A, we ablated L2-L4 ventral roots (VRs) to generate peripheral nerve animal model of pure sensory fibers. In group B, we ablated L2-L4 dorsal root ganglions (DRGs) to generate peripheral nerve animal model of pure motor fibers. Two time end-points were set as 2 weeks and 4 weeks. Neuron cells in lumbar spinal cords were detected by immunohistochemical staining with antibody of neuronal nuclei (NeuN). Motor neuron cells in lumbar spinal cords of pure motor fiber animal models and sensory neuron cells in lumbar spinal cords of pure sensory fiber animal models were counted respectively, and then compared to that of normal animals. Femoral nerves distal to the furcation were stained in osmium tetroxide, and then myelinated nerve fibers in the muscle branch and cutaneous branch of femoral nerve were counted respectively.

RESULTS

The mean numbers of sensory neuron cells and motor neuron cells in normal lumbar spinal cords were 62.57 ± 1.02 and 29.73 ± 3.03 per 10 × 20 visual field respectively. For different end-points, the mean numbers of sensory neuron cells after ablating vental foots were 62.12 ± 1.77 (2 weeks), 62.15 ± 1.32 (4 weeks) per 10 × 20 visual field respectively; the mean numbers of motor neuron cells after ablating DRGs were 30.12 ± 0.44 (2 weeks), 30.00 ± 1.87 (4 weeks) per 10 × 20 visual field respectively. In group A, motor axons in muscle branch were degenerated as the sensory axons in muscle branch and cutaneous branch were not changed. The senory axons in femoral nerve for the two end-points were 1 558.17 ± 50.14 (2 weeks) and 1 544.00 ± 47.42 (4 weeks). In group B, sensory axons in muscle branch were degenerated as the motor axons were reserved. The motor axons in muscle branch for the two end-points were 387.67 ± 48.50 (2 weeks) and 393.50 ± 27.86 (4 weeks). There was no statistically significant difference in these mean numbers for the two end-points. The degenerating axons and myelin sheath had not been totally eliminated by the endpoint of 2 weeks.

CONCLUSION

Peripheral nerve animal model of pure motor fibers can be generated by ablating L2-L4 DRGs; peripheral nerve animal model of pure sensory fibers can be generated by ablating L2-L4 ventral roots. The degenerating axons and myelin sheath have been totally eliminated by the end-point of 4 weeks. Ablating the ventral roots does not influence the survival of sensory neuron cells; and ablating the DRGs does not influence the survival of motor neuron cells.

[Radix hedysari extract promotes peripheral nerve regeneration]

Treatment of peripheral nerve injury is a major challenge in clinical practice. With advances in molecular biology and development of microsurgical techniques and tissue engineering, peripheral nerve repair procedures have been greatly improved. In the last 10 decades, most treatments for peripheral nerve injury in animal models have achieved histological and functional recovery, the treatments in humans, however, produce insufficient recovery, especially for proximal nerve injury. Increasing attention has been paid to the Traditional Chinese Medicine (TCM) for promoting peripheral nerve regeneration, since these remedies often display effective clinical outcome, minor side effects and effectiveness for multiple targets. Although TCM has complex ingredients and the specific pharmacological mechanisms for their effectiveness are still unclear, an effective clinical outcome is welcomed by many clinicians. In the past 20 years, we have made a series of detailed studies including the toxicity tests, pharmacodynamic tests, pharmacological experiments etc, about a new traditional formula which mainly contains the Radix hedysari, Epimedium etc. RESULTS have shown that this formula is safe to be used in both animals and humans with no toxicity and adverse effect, and systemic administration of this formula could enhance the peripheral nerve regeneration.

[Surgical treatment of deltoid ligament injury associated with ankle fractures]

OBJECTIVE

To observe the clinical outcome after the surgical treatment of the deltoid ligament injury associated with ankle fractures.

METHODS

From January 2005 to December 2009, 16 deltoid ligament ruptures associated with ankle fractures were repaired. According to the AO/OTA system, 2 cases belonged to fracture A, 8 to B, and 6 to C. Radiographs, American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scores and visual analogue scale (VAS) were used for the outcome measurements.

RESULTS

The 16 patients were followed up for 30 to 84 months,with the mean follow-up of 47 months. All wounds healed at the first stage. The mean time of bone union was 12.8 weeks (range: 10-14 weeks). The mean AOFAS ankle-hindfoot score in the last follow-up was 93 points (range: 85-100 points). The mean score of VAS was 0.94 points (range: 0-2 points).

CONCLUSION

Surgical treatment of ankle fractures associated with deltoid ligament rupture can achieve satisfactory outcomes, but it is important to decide the operation indication.

[Minimal invasive internal fixation with U-shaped break-off pedicle screws for treatent of thoracolumbar fractures]

OBJECTIVE

To investigate the clinical outcome of minimal invasive internal fixation with U-shaped break-off pedicle screws through paraspinal muscle sparing approach to treat thoracolumbar fractures, and to discuss its advantages.

METHODS

From August 2010 to June 2012, we had 40 thoracolumber fractures patients (27 males and 13 females). Their ages ranged from 22 to 60 years. Of the 40 cases, 4 were T11 fractures, 13 T12 fractures ,17 L1 fractures,6 L2 fractures. According to Denis classification,all of them were burst fractures, with vertebral canal compromise less than 1/3. According to AO classification they were type A or type B1 injuries. All the cases had no nerve injury. The patients were randomly divided into two groups. With Group A (20 cases) we took the method of minimal invasive internal fixation with U-shaped break-off pedicle screws to fix one level above and below the injured vertebra through the parespinal muscle sparing approach. With Group B (20 cases), we took the traditional posterior midline approach and open procedure. Then we compared the two groups by operation time, blood loss, drainage, Visual Analogue Scales and X-ray exposure.

RESULTS

Minimal invasive group had obvious advatages in operation time, bleeding control and early pain relief of post-operation. The X-ray exposure and long-term follow-up outcome were almost the same.

CONCLUSION

Through paraspinal muscle sparing approach minimal invasive internal fixtation with U-shaped break-off pedicle screws to treat thoracolumber has more advantages than traditional procedure in blood control and quick recovery. The method needs no special instruments and don't increase X-ray exposure.

[Treatment of comminuted clavicle shaft fractures with provisional intra-medullary K-wire fixation and bridging plate internal fixation]

OBJECTIVE

To discuss the operation effect of comminuted clavicle shaft fractures with provisional intramedullary K-wire fixation and bridging plate internal fixation.

METHODS

From Mar. 2008 to Jul. 2012, 22 cases of comminuted clavicle shaft fractures was treated with open reduction, and provisional intramedullary K-wire fixation and bridging plate internal fixation. The fracture healing was investigated through X-rays. The 22 cases were followed up to evaluate the function of the affected shoulder with Constant score.

RESULTS

Through the follow-up for average 15 months, all the fractures healed and the average healed time was 14.6 weeks. The average Constant score of the affected shoulder was 95.3. There were 13 excellent cases, 7 good cases, and 2 fair cases. The fineness rate was 90.9% (20/22). Soft tissue problem resulting from plate tilting occurred in 2 cases. At last, they accepted second operation to remove the implant.

CONCLUSION

Applying provisional intramedullary K-wire fixation and bridging plate internal fixation in comminuted clavicle shaft fractures, makes procedure simple, improves healing rate and decreases the complications.

Positioning study of cervical vertebra pedicle axial line projective point by computed tomography image reconstruction

BACKGROUND

Safe placement of the screws is a critical aspect of trans-pedicle internal fixation, and little information on in vivo morphology of the cervical vertebrae pedicle measured with imaging methods is available. The aim of this study was to measure the dimensions of cervical vertebrae C3 to C7 and provide screw length, screw diameter and tilt angle for clinical cervical vertebra trans-pedicle internal fixation.

METHODS

Thirty Chinese men and women underwent high-speed spiral computed tomography measurements to obtain data for C3 to C7, and the morphology of the cervical vertebra pedicles was reconstructed.

RESULTS

Reconstructed computer tomography image data revealed that: (1) pedicle sponge width increased incrementally from C3 to C7, (2) pedicle depth was similar for C3 to C7, (3) pedicle angle decreased incrementally from 47.20° to 33.76° for C3 to C7, and (4) pedicle point to midline distance was similar for C3 to C7. There were no statistical differences in morphological data between the right and the left side. Men had statistically larger values than women for all morphological parameters.

CONCLUSIONS

Reconstructed computed tomography images can provide useful data for clinical cervical vertebra trans-pedicle internal fixation. The individual measurement of cervical vertebra pedicles is recommended for safe placement of trans-vertebra pedicle screws.

Effects of Hedysari Polysaccharides on Regeneration and Function Recovery Following Peripheral Nerve Injury in Rats

It has been demonstrated that aqueous extract of Radix Hedysari Prescription and modified Radix Hedysari Prescription could improve the regeneration of injured peripheral nerve. Radix Hedysari is a main component in these two formulas. We hypothesized that Hedysari polysaccharides (HPS), a main active ingredient, could also enhance peripheral nerve regeneration after nerve injury in adult animals. In the present study, we examined the effects of HPS on sciatic nerve regeneration for 6 weeks following clamping in rats (administrated orally of 2 ml HPS liquid daily, 0.25 g/ml). The results showed that HPS was able to enhance sciatic function index (SFI) value, tibial function index (TFI) value, peroneal nerve function index (PFI) value, conduction velocity, and the number of regenerated myelinated nerve fibers, suggesting the potential clinical application of HPS for the treatment of peripheral nerve injury in humans.

Clinical effect of distal radius fracture treated with open reduction and internal plate fixation

BACKGROUND

For some specific comminuted unstable intra-articular fracture, the plaster cast can not maintain the alignment of the articular surface effectively. The aim of this study was to evaluate the clinical effects of distal radius fracture treated with open reduction and internal plate fixation retrospectively.

METHODS

From January 2002 to March 2010, 539 cases of distal radius fracture were treated with open reduction and internal fixation, including 184 males and 355 females aging 21 - 72 years (mean 57 years). Fractures were caused by falling to the ground in 459 cases, by traffic accident in 62 cases and by athletic injuries in 18 cases. Of 539 cases, there were 523 cases of closed fracture and 16 cases of open fracture. According to Arbeitsgemeinschaft fur Osteosynthesefragen (AO) standards of classification, there were 14 cases of A2 type, 22 of A3 type, 18 of B1 type, 24 of B2 type, 62 of B3 type, 91 of C1 type, 162 of C2 type and 146 of C3 type. The time from injury to operation was 1 - 16 days (mean 5 days). All patitents received open reduction and internal plate screw fixation. Forty-seven patients with bone defect were given 6 - 15 g autologous ilium and 75 cases were given 5 ml calcium sulphate artificial aggregate after reduction.

RESULTS

All incisions healed by first intention after operation. Patients were followed up for 15 to 32 months postoperatively (mean 22 months). The fractures healed within 10 - 18 weeks after operation (mean 12 weeks). During the last follow-up, the mean palmar tilt was (7.0 ± 0.9)° and the mean ulnar variance was (21.0 ± 4.2)°, showing significant difference when compared with preoperation ((-5.0 ± 1.2)° and (8.0 ± 3.8)°). The radial heights were not abbreviated. According to Gartland and Werley assessment system, the results were excellent in 314 cases, good in 163 cases, fair in 46 cases, and poor in 16 cases 12 weeks after operation, the excellent and good rate was 88.5%.

CONCLUSIONS

The clinical effect of distal radius fracture treated with open reduction and internal plate fixation was relatively satisfactory. Meticulous operation procedure and individual rehabilitation strategy contribute to the wrist joint functional recovery.

Overall anatomical features and clinical value of the sacral nerve in high resolution computed tomography reconstruction

BACKGROUND

Sacral nerve injury is a common complication of pelvic or sacral fractures. As the sacral nerve courser within the sacrum and has a complex relationship with the surrounding tissues, different parts of the sacral plexus injury have similar clinical symptoms and signs. Since lack of specific imaging technique in the diagnosis of sacral nerve injury, especially on multi-segment, multi-site, how to determine the preoperative location and extent of the sacral nerve injury accurately becomes a concern of the general orthopaedic and images practitioners. This study was conducted to gain an insight into the overall anatomical features of the sacral nerve (SN) on the same slice in high resolution computed tomography (HRCT) reconstruction and to determine the value of this information for the clinical diagnosis of related diseases.

METHODS

Fifty healthy volunteers and 30 patients (40 sides) with SN lesions confirmed by surgery were scanned using a 16-slice helical CT scanner (Light Speed, GE, USA). Among the patients, 6 with intervertebral disk hernia (6 sides), 8 with spinal stenosis (12 sides), 11 with pelvic trauma (14 sides), 4 with pelvic malignancies (6 sides), and 1 with sacral vertebral tuberculosis (2 sides). The SN multiplanar reconstruction was performed using a UNIX-based SCD4.1 workstation where the image was set on the same slice. All images were stored in the Digital Imaging and Communications in Medicine format. The display of nerves in different sections was analyzed using a five-graded scale with coordinate curves of each individual score. The overall anatomic features visible on the slice were analyzed and the abnormalities of the lesions were studied.

RESULTS

The image of the same slice clearly revealed the shape, running direction, thickness, tension and adjacent anatomy of the S1-S4 nerves. The rank of display rates in different sections was: outward-rotated oblique sagittal > outward-rotated oblique coronal > oblique coronal plane > coronal > sagittal > transverse section. The S5 nerve was partially displayed from the starting point to the segment around the posterior sacral foramen. The overall anatomy of the triangular sacral plexus was only revealed in the oblique outward-rotated sagittal section, while 100% of its individual rami, as well as two or three of the adjacent rami, were displayed from their starting points to the anterior border of the piriformis. The abnormalities included 39 sides of morphological change (97.5%), 38 sides of compression (95.0%), 35 sides of adhesion (87.5%), 32 sides of displacement (80.0%), 34 sides of shrinkage (85.0%), 6 sides of thickening (15.0%), and 2 sides of abruption (5.0%).

CONCLUSIONS

The 16-slice CT multiplanar reconstruction was able to reveal the overall anatomic features of the SN on the same slice. The section of reconstruction was a crucial factor in determining the display capability of various sacral nerves. This technology was valuable in the diagnosis and management of related diseases.

Calcitonin gene-related peptide induces proliferation and monocyte chemoattractant protein-1 expression via extracellular signal-regulated kinase activation in rat osteoblasts

BACKGROUND

Calcitonin gene-related peptide (CGRP), a sensory neuropeptide, affects osteoblast proliferation and bone formation. However, the mechanisms are not fully understood. Monocyte chemoattractant protein-1 (MCP-1) is a chemokine that stimulates the migration of monocytes and plays important roles in regulating bone remolding during fracture repair. In this study, we investigated the effects of CGRP on proliferation and MCP-1 expression in cultured rat osteoblasts.

METHODS

Primary rat osteoblasts were isolated from fetal rats calvariae. Cells were exposed to gradient concentrations (10(-9) to 10(-7) mol/L) of CGRP. Protein and mRNA levels of MCP-1 were quantified by Western blotting and semiquantitative reverse transcription-polymerase chain reaction, respectively. The protein level of MCP-1 was investigated and compared in cell culture media by enzyme linked immunosorbent assay (ELISA). Phospho-extracellular signal-regulated kinase (ERK) expression was detected by Western blotting. Cell proliferative activity was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and BrdU assay. The effects of MAPK/ERK kinase (MEK)-inhibitor U0126 on CGRP-induced MCP-1 expression in primary rat osteoblasts were examined.

RESULTS

CGRP effectively enhanced primary rat osteoblast proliferation and led to significant increases in the expression of MCP-1 mRNA and protein in time- and dose-dependent manners. CGRP activated the ERK pathway. Pretreatment of cultured rat osteoblasts with MEK inhibitor U0126 resulted in dose-dependent inhibitions of CGRP-induced MCP-1 mRNA and protein levels. Thus, CGRP promoted cell proliferation and stimulated MCP-1 expression in cultured rat osteoblasts.

CONCLUSION

These studies document novel links between CGRP and MCP-1 and illuminate the effects of CGRP in regulating bone remodeling.

EGFP Expression Controlled by GFAP Promoter in Mesenchymal Cells: An Efficient Tool for Glial Lineage Selection and Transplantation

In order to demonstrate a new method to label and select enough glial cells from induced MSCs to provide cells for cell therapy, MSCs were induced with Beta-mercaptoethanol followed by retinoic acid, forskolin, basic-FGF, PDGF and heregulin. Induced MSCs were transfected with reconstructed vector pGFAP-EGFP by inserting GFAP promotor into pEGFP-N3 to substitute CMV promotor. Living cells against G418 were enriched and checked by flowcytometry. EGFP expressing cells were sorted and used for transplantation in vivo. Immunoelectronmicroscopy was accomplished using anti-EGFP to relocalize the transplanted cells. Almost all MSCs took on phenotypes of glial cells after induction, expressing S100 and GFAP. The EGFP expression rate of survived MSCs against G418 was 82.74%. Glial cells expressing EGFP accumulated mainly around the damaged nerve fibers. MSCs were relocalized by immunoelectronmicroscopy and remyelination was observed. EGFP expression controlled by GFAP promoter in mesenchymal cells was an efficient tool for glial lineage selection and transplantation. Induced MSCs can promote nerve regeneration by participating remyelination.

[The prospective study project of 62 cases spinal cord injury]

OBJECTIVE

To rudiment analyze the different intervention factors affecting the spinal cord injury functional recovery initially through prospective study project.

METHODS

Designed prospective study project without clinical treatment intervention and admitted 62 spinal cord injury cases into observation group from Dec 2006 to Dec 2007. The internalized standard included acute spinal cord injury within 1 week, aged from 18 to 65 years old without sexuality difference and diagnosed as type A injury: total spinal cord injury or type B injury: non-total spinal cord injury (without movement function below the injury plane) according to clinical physical examination and combined MRI or CT examination. All the 62 cases were followed up. The spinal cord function were estimated at the time of arriving hospital, 1, 3, 6 months after injury during the following up time according to the American Spine Injury Association standard (Revised at 2000) and functional independence measure (FIM) score. The intervention factors affecting the spinal cord injury functional recovery were analyzed.

RESULTS

Among the 62 cases, male 60 cases and female 2 cases, aged from 18 to 41 years old, mean age 24 years old, 29 cases can be classified into type A injury and 33 cases can be classified into type B injury. There was no significant difference (Index including sense ASIA, motor ASIA and FIM) between operation group and non-operation group, namely conservatively composite treatment at all observation point in all type A injury cases (P > 0.05). There was significant difference (Index including sense ASIA, motor ASIA and FIM) between operation group and non-operation group at all observation point in all type B injury cases (P < 0.05); And there was significant difference (Index including sense ASIA, motor ASIA and FIM) between operated in 8 hours (< or = 8 h) group and beyond 8 hours (> 8 h) group at all observation point in all type B operated cases (P < 0.05).

CONCLUSIONS

Operation and operation time were of no significant value for type A injury (total spinal cord injury), but considering the nursing convenience and the need for spinal stabilities, operation decompression and internal fixation can be chosen; Operation decompression should be performed as soon as quickly for type B injury (non-total spinal cord injury) in order to get better functional recovery.

Fourier Transform Raman and Density Functional Theory Studies on the Adsorption Behavior of p-Hydroxybenzoic Acid on Silver Nanoparticles

Two models of p-hydroxybenzoic acid (PHBA) adsorbed on the surfaces of silver nanoparticles were established, each of them corresponding to an experimental configuration. The first model is PHBA adsorbed on one Ag atom through the carboxyl group, and the second one is PHBA adsorbed on two Ag atoms through the carboxyl and hydroxyl groups. The Raman spectra of these two models using DFT-B3PW91 with lanl2dz were calculated; it was found that the calculated Raman frequencies were in good agreement with experimental values. So one can conclude that the simplified models are probably reasonable to describe some surface-enhanced Raman experiments.

Study on the adoption of Schwann cell phenotype by bone marrow stromal cells in vitro and in vivo

OBJECTIVE

To explore the possibilities of bone marrow stromal cells (MSCs) to adopt Schwann cell phenotype in vitro and in vivo in SD rats.

METHODS

MSCs were obtained from tibia and femur bone marrow and cultured in culture flasks. Beta-mercaptoethanol followed by retinoic acid, forskolin, basic-FGF, PDGF and heregulin were added to induce differentiation of MSCs'. Schwann cell markers, p75, S-100 and GFAP were used to discriminate induced properties of MSCs' by immunofluorescent staining. PKH-67-labelled MSCs were transplanted into the mechanically injured rat sciatic nerve, and laser confocal microscopy was performed to localize the PKH67 labelled MSCs in the injured sciatic nerve two weeks after the operation. Fluorescence PKH67 attenuation rule was evaluated by flow cytometry in vitro.

RESULTS

MSCs changed morphologically into cells resembling primary cultured Schwann cells after their induction in vitro. In vivo, a large number of MSCs were cumulated within the layer of epineurium around the injured nerve and expressed Schwann cell markers, p75, S-100, and GFAP.

CONCLUSION

MSCs are able to support nerve fiber regeneration and re-myelination by taking on Schwann cell function, and can be potentially used as possible substitutable cells for artificial nerve conduits to promote nerve regeneration.

Transfer of activation-dependent gene expression into T cell lines by recombinant adeno-associated virus

We examined the ability of recombinant adeno-associated virus (rAAV) to transfer regulated gene expression into T cell lines. An AAV-based vector containing the neomycin resistance gene and expressing the firefly luciferase (luc) gene under the regulatory control of the interleukin 2 promoter (pAAV-luc) was generated and adenovirus-free rAAV (rAAV-luc) was produced from this vector. Transfection of pAAV-luc into the human T cell line Jurkat resulted in luciferase expression while infection of Jurkat T cells with rAAV-luc resulted in significant luciferase expression only after selection for neomycin-resistant cells. Long-term growth of transduced Jurkat T cells showed that there was no detectable constitutive expression of luciferase and that luciferase gene expression remained inducible for at least 180 days. Luciferase expression was activated by PMA and ionomycin and by anti-CD3 antibodies and was inhibited by cyclosporin A. Examination of G418-resistant clones showed that rAAV-luc had integrated into the host chromosomes but that some of the clones lost some of the transferred DNA or lost expression from the transferred DNA. These results indicate that rAAV can transfer and integrate regulated gene expression into T cell lines but that the transferred genetic material may be lost or its expression may be silenced over time.

[Multiple types of cytokines secreted by a mouse fetal liver stromal cell line]

A murine fetal liver stromal cell line, called MFLC, has been established and maintained in DME supplemented with 10%NCS for 2 years. Without exogenous stimulation, the MFLC cells spontaneously secreted several types of cytokines, including IL-6, GM-CSF and chemotactic factor. Of which, IL-6 and chemotactic factor were abundant, GM-CSF at low level. Biological activities of IL-7 and IL-3 were not detected in the MFLC cell's supernatants. MFLC-SN induced colony formation of murine bone marrow cells in a dose dependent fashion in which mixed granulocyte/macrophage/megakaryocyte colonies(CFU-GMM) and granulocyte/macrophage colonies(CFU-GM) were dominant. MFLC-SN also sustained colony formation of bone marrow cells taken from 5-Fu injected mice, suggesting that there was a biological activity similar to SCF in MFLC-SN. The cytokines secreted by MFLC might play an important role in T cell early development in fetal liver. These results will be useful for us to analyse the mechanism of T cell development in fetal liver and to study the cytokine network regulation.

Study of simplified measures for malaria surveillance in the late consolidation phase in China

This paper presents the results of a study on simplified surveillance methods conducted in 23 pilot counties in 11 provinces and municipalities in China where reside 15 million people and malaria control has been in the late consolidation phase. Two simplified surveillance Schemes (A and B) taking treatment of clinical cases as the main measure were implemented in 1992-1994. The rate of annual blood examination for case detection was 1.0% in pilot Scheme A, while in areas of scheme B it was 0.3%. The implementation of both Scheme A and Scheme B, simplified or without treatment of infection foci and management of mobile populations, acquired satisfactory effects against malaria. Consequently, malaria incidence was declining steadily, only a few indigenous and introduced cases were detected. The parasite rate in residents and the IFA positive rate in children were very low. The results of pilot studies and cost-effectiveness analysis indicated that Scheme B is effective, rational and economic, and can be implemented to replace the routine surveillance measures in areas where malaria has been at the late consolidation phase in China.

[Cytokine production by MTSC 4 cells, an established mouse thymic dendritic cell line]

The cytokine production by MTSC 4 cells, a murine thymic dendritic cell line established in our laboratory, has been investigated. Without exogenous stimulation, the MTSC 4 cells constitutively produce multiple types of cytokines, including IL-1, IL-6, IL-7, CSF, IFN and Chemotactic factor (CF). Of which, IL-6 and IFN were abundant: IL-1 and Chemokine, moderate: IL-7 and CSF at low level. MTSC4 cells could not produce detectable either IL-3 of TNF alpha. The establishment of MTSC 4 may be useful in the analysis of the mechanism of thymus selection, and in the study of the network regulation of autocrined cytokines.

Multiple types of cytokines constitutively produced by an established murine thymic epithelial cell line

An untransformed murine thymic epithelial cell line (MTEC1) has been established. Without exogenous stimulation, the MTEC1 cells constitutively produced multiple types of cytokines, including IL-1, IL-6, IL-7, GM-CSF and chemotactic factor(s). Of which, IL-6, GM-CSF and chemotactic factor(s) were abundant; IL-1, moderate; and IL-7 at low level. MTEC1 cells neither produced detectable IL-3 nor TNF alpha. Thus, the MTEC1 cells may be useful not only in the evaluation of the signals required for thymic selection in vitro, but also useful in the analysis of the endogenous regulation of the autocrine cytokine production cascade.