Ruxolitinib improves the inflammatory microenvironment, restores glutamate homeostasis, and promotes functional recovery after spinal cord injury

JOURNAL/nrgr/04.03/01300535-202419110-00030/figure1/v/2024-03-08T184507Z/r/image-tiff The inflammatory microenvironment and neurotoxicity can hinder neuronal regeneration and functional recovery after spinal cord injury. Ruxolitinib, a JAK-STAT inhibitor, exhibits effectiveness in autoimmune diseases, arthritis, and managing inflammatory cytokine storms. Although studies have shown the neuroprotective potential of ruxolitinib in neurological trauma, the exact mechanism by which it enhances functional recovery after spinal cord injury, particularly its effect on astrocytes, remains unclear. To address this gap, we established a mouse model of T10 spinal cord contusion and found that ruxolitinib effectively improved hindlimb motor function and reduced the area of spinal cord injury. Transcriptome sequencing analysis showed that ruxolitinib alleviated inflammation and immune response after spinal cord injury, restored EAAT2 expression, reduced glutamate levels, and alleviated excitatory toxicity. Furthermore, ruxolitinib inhibited the phosphorylation of JAK2 and STAT3 in the injured spinal cord and decreased the phosphorylation level of nuclear factor kappa-B and the expression of inflammatory factors interleukin-1β, interleukin-6, and tumor necrosis factor-α. Additionally, in glutamate-induced excitotoxicity astrocytes, ruxolitinib restored EAAT2 expression and increased glutamate uptake by inhibiting the activation of STAT3, thereby reducing glutamate-induced neurotoxicity, calcium influx, oxidative stress, and cell apoptosis, and increasing the complexity of dendritic branching. Collectively, these results indicate that ruxolitinib restores glutamate homeostasis by rescuing the expression of EAAT2 in astrocytes, reduces neurotoxicity, and effectively alleviates inflammatory and immune responses after spinal cord injury, thereby promoting functional recovery after spinal cord injury.

Necroptosis pathway emerged as potential diagnosis markers in spinal cord injury

The present research focused on identifying necroptosis-related differentially expressed genes (NRDEGs) in spinal cord injury (SCI) to highlight potential therapeutic and prognostic target genes in clinical SCI. Three SCI-related datasets were downloaded, including GSE151371, GSE5296 and GSE47681. MSigDB and KEGG datasets were searched for necroptosis-related genes (NRGs). Differentially expressed genes (DEGs) and NRGs were intersected to obtain NRDEGs. The MCC algorithm was employed to select the first 10 genes as hub genes. A protein-protein interaction (PPI) network related to NRDEGs was developed utilizing STRING. Several databases were searched to predict interactions between hub genes and miRNAs, transcription factors, potential drugs, and small molecules. Immunoassays were performed to identify DEGs using CIBERSORTx. Additionally, qRT-PCR was carried out to verify NRDEGs in an animal model of SCI. Combined analysis of all datasets identified 15 co-expressed DEGs and NRGs. GO and KEGG pathway analyses highlighted DEGs mostly belonged to pathways associated with necroptosis and apoptosis. Hub gene expression analysis showed high accuracy in SCI diagnosis was associated with the expression of CHMP7 and FADD. A total of two hub genes, i.e. CHMP7, FADD, were considered potential targets for SCI therapy.

Extradural contralateral S1 nerve root transfer for spastic lower limb paralysis

The current study aims to ascertain the anatomical feasibility of transferring the contralateral S1 ventral root (VR) to the ipsilateral L5 VR for treating unilateral spastic lower limb paralysis. Six formalin-fixed (three males and three females) cadavers were used. The VR of the contralateral S1 was transferred to the VR of the ipsilateral L5. The sural nerve was selected as a bridge between the donor and recipient nerve. The number of axons, the cross-sectional areas and the pertinent distances between the donor and recipient nerves were measured. The extradural S1 VR and L5 VR could be separated based on anatomical markers of the dorsal root ganglion. The gross distance between the S1 nerve root and L5 nerve root was 31.31 (± 3.23) mm in the six cadavers, while that on the diffusion tensor imaging was 47.51 (± 3.23) mm in 60 patients without spinal diseases, and both distances were seperately greater than that between the outlet of S1 from the spinal cord and the ganglion. The numbers of axons in the S1 VRs and L5 VRs were 13414.20 (± 2890.30) and 10613.20 (± 2135.58), respectively. The cross-sectional areas of the S1 VR and L5 VR were 1.68 (± 0.26) mm 2 and 1.08 (± 0.26) mm 2, respectively. In conclusion, transfer of the contralateral S1 VR to the ipsilateral L5 VR may be an anatomically feasible treatment option for unilateral spastic lower limb paralysis.

Development and Clinical Trial of a New Orthopedic Surgical Robot for Positioning and Navigation

Robot-assisted orthopedic surgery has great application prospects, and the accuracy of the robot is the key to its overall performance. The aim of this study was to develop a new orthopedic surgical robot to assist in spinal surgeries and to compare its feasibility and accuracy with the existing orthopedic robot. A new type of high-precision orthopedic surgical robot (Tuoshou) was developed. A multicenter, randomized controlled trial was carried out to compare the Tuoshou with the TiRobot (TINAVI Medical Technologies Co., Ltd., Beijing) to evaluate the accuracy and safety of their navigation and positioning. A total of 112 patients were randomized, and 108 patients completed the study. The position deviation of the Kirschner wire placement in the Tuoshou group was smaller than that in the TiRobot group (p = 0.014). The Tuoshou group was better than the TiRobot group in terms of the pedicle screw insertion accuracy (p = 0.016) and entry point deviation (p < 0.001). No differences were observed in endpoint deviation (p = 0.170), axial deviation (p = 0.170), sagittal deviation (p = 0.324), and spatial deviation (p = 0.299). There was no difference in security indicators. The new orthopedic surgical robot was highly accurate and optimized for clinical practice, making it suitable for clinical application.

A Case of Daratumumab-Induced Significant Decrease in Donor-Specific HLA Antibodies and Remission Induction Before Haploidentical Stem Cell Transplantation in a Refractory B-ALL Patient

Objective:

To explore the method of eliminating donor-specific anti-HLA antibodies (DSA) in haploidentical stem cell transplantation (haplo-SCT).

Methods:

We present a refractory B-cell acute lymphoblastic leukemia (ALL) patient who had strongly positive DSA, but had no human leukocyte antigen–matched donor. Although CD38 expression on leukemia cells was negative, daratumumab combined with etoposide and venetoclax therapy was chosen for her.

Results:

She achieved a significant decrease in DSA levels and complete remission on the combination therapy with daratumumab. She then received a haplo-SCT from a daughter as a donor and had a successful engraftment of donor stem cell. In haplo-SCT, strongly positive DSA levels, directed against donor HLA antigens, could be significantly reduced by daratumumab therapy before transplantation and successfully bridge subsequent haplo-SCT.

Conclusion:

Although CD38 expression is negative in leukemia cells, refractory B-ALL patients may still benefit from combination therapy with daratumumab. We need further clinical observation.

Locomotor Exercise Enhances Supraspinal Control of Lower-Urinary-Tract Activity to Improve Micturition Function after Contusive Spinal-Cord Injury

The recovery of lower-urinary-tract activity is a top priority for patients with spinal-cord injury. Historically, locomotor training improved micturition function in both patients with spinal cord injury and animal models. We explore whether training augments such as the supraspinal control of the external urethral sphincter results in enhanced coordination in detrusor-sphincter activity. We implemented a clinically relevant contusive spinal-cord injury at the 12th thoracic level in rats and administered forced wheel running exercise for 11 weeks. Awake rats then underwent bladder cystometrogram and sphincter electromyography recordings to examine the micturition reflex. Subsequently, pseudorabies-virus-encoding red fluorescent protein was injected into the sphincter to trans-synaptically trace the supraspinal innervation of Onuf's motoneurons. Training in the injury group reduced the occurrence of bladder nonvoiding contractions, decreased the voiding threshold and peak intravesical pressure, and shortened the latency of sphincter bursting during voiding, leading to enhanced voiding efficiency. Histological analysis demonstrated that the training increased the extent of spared spinal-cord tissue around the epicenter of lesions. Compared to the group of injury without exercise, training elicited denser 5-hydroxytryptamine-positive axon terminals in the vicinity of Onuf's motoneurons in the cord; more pseudorabies virus-labeled or c-fos expressing neurons were detected in the brainstem, suggesting the enhanced supraspinal control of sphincter activity. Thus, locomotor training promotes tissue sparing and axon innervation of spinal motoneurons to improve voiding function following contusive spinal-cord injury.

A comparison of robot-assisted and fluoroscopy-assisted kyphoplasty in the treatment of multi-segmental osteoporotic vertebral compression fractures

Osteoporotic vertebral compression fracture (OVCF) has become a major public health issue that becomes more pressing with increasing global aging. Percutaneous kyphoplasty (PKP) is an effective treatment for OVCF. Robot-assisted PKP has been utilized in recent years to improve accuracy and reduce complications. However, the effectiveness of robot-assisted PKP in the treatment of multi-segmental OVCF has yet to be proved. This study was designed to compare the efficacy of robot-assisted and conventional fluoroscopy-assisted multi-segmental PKP. A total of 30 cases with multi-segmental OVCF between April 2019 and April 2021 were included in this study. Fifteen cases were assigned to the robot-assisted PKP group (robot group) and 15 cases to the conventional fluoroscopy-assisted PKP group (conventional fluoroscopy group). The number of fluoroscopic exposures, fluoroscopic dose, operation time, cement leakage rate, visual analog scale (VAS) score, vertebral kyphosis angle (VKA), and height of fractured vertebral body (HFV) were compared between the 2 groups. The number of fluoroscopic exposures, fluoroscopic doses, and cement leakage rates in the robot group were lower than in the conventional fluoroscopy group (P<0.05) while the operative time in the robot group was longer than in the conventional fluoroscopy group (P<0.05). VAS score and VKA were decreased and HFV was increased after surgery in both groups (P<0.05). Therefore, robot-assisted PKP for the treatment of multi-segmental OVCF can reduce the number of fluoroscopic exposures, fluoroscopic doses, and cement leakage compared to conventional treatment. As such, robot-assisted PKP has good application prospects and is potentially more effective in the treatment of multi-segmental OVCF.

Application of Extradural Nerve Root Transfer in the Restoration of Lower Limb Function in Spinal Cord Injury: Hypothesis and a Cadaver Feasibility Study

STUDY DESIGN

Two fresh-frozen and six formalin-fixed cadavers were included in the study.

OBJECTIVE

To ascertain whether transferring T9 or T11 ventral root (VR) to L2 VR and T10 or T12 VR to L3 VR in restoring lower limb function after spinal cord injury is anatomically feasible.

SUMMARY OF BACKGROUND DATA

Lower limb paralysis impairs the quality of the life and places burden on the whole society. However, no significant improvement in this area was achieved during recent years.

METHODS

In the present study, two fresh-frozen and six formalin-fixed cadavers were dissected to confirm the anatomical feasibility. A limited laminectomy was performed to expose the T9-L3 extradural nerve roots. T9 and T10 VR were anastomosed to L2 and L3 VR respectively, or T11 and T12 VR were anastomosed to L2 and L3 VR respectively. The pertinent distances between the donor and recipient nerves were measured and H&E staining was used to detect the axon number and cross-section area of each VR.

RESULTS

The limited incision was performed to expose the T9-L3 nerve root. According to the anatomic landmark of dorsal root ganglion, each VR could be isolated from each extradural nerve root. The T9 or T11 VR needs sural nerve graft to be transferred to L2 VR, and T10 or T12 VR also needs a nerve bridge to connect to L3 VR. The nerve numbers of T9, T10, T11, T12, L2, and L3 VRs and the sural nerves were measured respectively. The cross-section areas of T9, T10, T11, T12, L2, and L3 VRs and sural nerves were measured respectively.

CONCLUSION

Our study suggested that application of transferring T9 or T11 VR to L2 VR and T10 or T12 VR to L3 VR in restoring lower limb function is anatomically feasible.Level of Evidence: 5.

CD19 CAR-T cell treatment conferred sustained remission in B-ALL patients with minimal residual disease

The persistence or recurrence of minimal residual disease (MRD) after chemotherapy predicts relapse of B-cell acute lymphoblastic leukemia (B-ALL). CD19-directed chimeric antigen receptor T (CD19 CAR-T) cells have shown promising responses in B-ALL. However, their role in chemotherapy-refractory MRD-positive B-ALL remains unclear. Here we aimed to assess the effectiveness and safety of CD19 CAR-T cells in MRD-positive B-ALL patients. From January 2018, a total of 14 MRD-positive B-ALL patients received one or more infusions of autogenous CD19 CAR-T cells. Among them, 12 patients achieved MRD-negative remission after one cycle of CAR-T infusion. At a median follow-up time of 647 days (range 172–945 days), the 2-year event-free survival rate in MRD-positive patients was 61.2% ± 14.0% and the 2-year overall survival was 78.6 ± 11.0%, which were significantly higher than patients with active disease (blasts ≥ 5% or with extramedullary disease). Moreover, patients with MRD had a lower grade of cytokine release syndrome (CRS) than patients with active disease. However, the peak expansion of CAR-T cells in MRD positive patients showed no statistical difference compared to patients with active disease. Five patients received two or more CAR-T cell infusions and these patients showed a decreased peak expansion of CAR-T cell in subsequent infusions. In conclusion, pre-emptive CD19 CAR-T cell treatment is an effective and safe approach and may confer sustained remission in B-ALL patients with chemotherapy-refractory MRD. The trials were registered at www.chictr.org.cn as ChiCTR-ONN-16009862 (November 14, 2016) and ChiCTR1800015164 (March 11, 2018).

Comparison of the modified Wiltse's approach with spinal minimally invasive system and traditional approach for the therapy of thoracolumbar fracture

Thoracolumbar fractures are usually treated by open posterior pedicle screw fixation. However, this procedure involves massive paraspinal muscle stripping, inflicting surgical trauma, and prolonged X-ray exposure. In this study, we observed 127 patients with single-segment injury thoracolumbar fractures. Thirty-six patients were treated by the modified Wiltse's paraspinal approach with minimally invasive channel system, while 91 patients were treated via traditional posterior approach. Operation time, intraoperative blood loss, intraoperative fluoroscopy frequency, screw placement accuracy, visual analogue scale score, and Cobb's angle of two groups were compared. The X-ray exposure times were notably reduced (4.2±1.6) in the new approach group (P<0.05). The pedicle screw placement accuracy and Cobb's angle after surgery were similar in the two groups. We conclude that modified Wiltse's paraspinal approach with spinal minimally invasive channel system surgery can significantly reduce the X-ray exposure times and is an alternative therapy for the thoracolumbar fracture.

A multi-level drill guide template improves the accuracy of pedicle screw placement in lumbar spine

OBJECTIVE

Free-hand technique is widely used in pedicle screw placement for lumbar spine and generally safe; however, screw malposition still occurs. To develop a novel multi-level drill guide template for pedicle screw placement in lumbar spine and evaluate its accuracy.

MATERIALS AND METHODS

Twelve lumbar cadaveric specimens were randomly allocated into guide template group (n=6) and free-hand group (n=6). Computed tomography (CT) scans were obtained for reconstruction of three-dimensional (3D) model of each lumbar vertebra, and further an individual guide template was designed. Then the templates and their corresponding vertebra were developed by rapid prototyping (RP) technology. With the guide of the templates, screws were inserted via mini-open Wiltse approach. The positions of the screws were assessed based on postoperative CT images.

RESULTS

In total, 120 pedicle screws inserted (guide template group: n=60 vs. free-hand group: n=60). For all 30 vertebras in the guide template group, all pre-designed personalized drill guide templates can be fitted into the facet joints of each vertebra well. Furthermore, our results revealed a significant improvement for the guide template group in the accuracy rate (p=0.026).

CONCLUSIONS

Armed with advantages of minimal invasion, enhanced accuracy and safety, the novel technique of multi-level drill guide template can be properly applied in pedicle screw placement for lumbar spine and promises to be a potential option in clinical application.

Cervical intradural disc herniation with Brown-Séquard syndrome: case report and literature review

Objective

To report a rare case of cervical intradural disc herniation (IDH) with Brown-Séquard syndrome and to review the related literature.

Methods

Pathogenesis, preoperative diagnosis, and the surgical technique are discussed, and previous literature reports are reviewed.

Results

A 44-year-old woman complained of weakness of the left upper and lower extremities and paresthesias in the right limbs after a bicycle ride 3 days earlier. She had a history of neck pain for 2 years prior. CT showed obvious ossification of the posterior longitudinal ligament (OPLL), and MRI revealed C3-7 disc herniations, with a positive “halo sign” around the herniated C4/5. We performed emergency decompression through anterior cervical corpectomy, and vertebrotomy decompression and fusion. At review 3 months after surgery, the patient’s neck pain was markedly relieved, and motor strength in the limbs had improved. At 1 year after surgery, she had recovered completely.

Conclusion

Cervical IDH is a rare condition that may be related to the traumatic inflammatory response and OPLL. Relatively rare imaging features such as the hawk-beak sign, halo sign, Y sign, and epidural gas sign could help in preoperative diagnosis. Prompt anterior cervical decompression is the preferred treatment for this condition.

[Efficacy and safety of CD19 chimeric antigen receptor T cells for the treatment of 22 patients with B-cell lymphoma]

目的

探讨CD19 CAR-T治疗B细胞淋巴瘤的疗效及安全性。

方法

评估2017年2月1日至2018年7月1日CD19 CAR-T治疗22例B细胞淋巴瘤患者的疗效及不良反应情况。

结果

22例患者输注CD19 CAR-T后，总体完全缓解（CR）率为45.5%，部分缓解（PR）率为31.8%，总有效率为77.3%。其中12例复发难治患者9例有效，2例达CR，7例PR；10例微小残留病（MRD）阳性患者，8例MRD转阴。全部患者外周血中均检测到CD19 CAR-T细胞在体内增殖，复发难治患者与MRD阳性患者T细胞增殖的达峰时间分别为治疗后第4.5（1~12）天和治疗后第12（5~19）天，外周血CAR-T细胞分别占总的T淋巴细胞的4.02%（2.23%~28.60%）和10.10%（3.55%~24.74%）。MRD转阴患者持续缓解，中位随访8（3~18）个月均未复发，且此组患者有3例联合PD-1抗体治疗，均达CR。复发难治患者中，7例CAR-T治疗后达PR患者疗效保持时间为1.5~6.0个月，PD-1表达率为25.7%~55.3%，5例CAR-T治疗无效患者PD-1均高表达；共有3例患者联合应用PD-1抗体，其中2例有效；2例CAR-T治疗后达CR患者中1例行异基因造血干细胞移植，另1例随访12个月仍持续缓解。22例患者输注CAR-T细胞后14例发生不同程度的细胞因子释放综合征（CRS），其中9例为1级CRS，4例为2级CRS，其中1例复发难治患者发生3级CRS，经糖皮质激素、IL-6抗体治疗后CRS得到控制。治疗有效的17例患者中14例发生CRS，治疗无效的5例患者均未发生CRS。难治复发患者发生CRS的严重程度高于MRD阳性患者。

结论

CD19 CAR-T在CD19⁺ B细胞淋巴瘤中取得了疗效。CAR-T联合免疫检查点抑制剂的应用能够更好地提高疗效，CAR-T细胞治疗可作为复发难治患者的挽救治疗，清除B细胞淋巴瘤的MRD效果更好且不良反应小。

A novel extradural nerve transfer technique by coaptation of C4 to C5 and C7 to C6 for treating isolated upper trunk avulsion of the brachial plexus

The study aimed to demonstrate the feasibility of an extradural nerve anastomosis technique for the restoration of a C5 and C6 avulsion of the brachial plexus. Nine fresh frozen human cadavers were used. The diameters, sizes, and locations of the extradural spinal nerve roots were observed. The lengths of the extradural spinal nerve roots and the distance between the neighboring nerve root outlets were measured and compared in the cervical segments. In the spinal canal, the ventral and dorsal roots were separated by the dura and arachnoid. The ventral and dorsal roots of C7 had sufficient lengths to anastomose those of C6. The ventral and dorsal of C4 had enough length to be transferred to those of C5, respectively. The feasibility of this extradural nerve anastomosis technique for restoring C5 and C6 avulsion of the brachial plexus in human cadavers was demonstrated in our anatomical study.

Biomechanical strength impact of lateral wall breach on spinal pedicle screw fixation

OBJECTIVE

The purpose of our study was to make a comparison between the fixation strength of optimum placed pedicle screw (OS) and re-directionally accurate placed pedicle screw (RS) after lateral pedicle breach.

PATIENTS AND METHODS

A total of 30 fresh lumbar vertebrae (L1-5) were gained from 6 male or female pigs weighing about 100 kg, which were divided into 2 groups according to different ways of pedicle screws placement: OS group (n=30) and RS group (n=30). MTS machine was employed to detect the screw loosening and axial pullout. We examined seating torque, screw-loosening force, the maximal torque and post-loosening axial pullout in each pedicle screw.

RESULTS

Maximal insertion torque of OS was (111.6±8.4) N•cm and RS was (79.0±6.3) N•cm, which indicated a significant difference (Z=3.012, p=0.003). Seating torque of OS and RS were (85.9±5.6) N•cm and (60.3±4.8) N•cm separately, and the difference was statistically significant (Z=2.799, p=0.006). Screw loosening force of OS and RS were (75.9±7.0) N and (52.4±6.3) N respectively, and the difference was statistically significant (Z=2.652, p=0.003). Post-loosening axial pullout force of OS and RS were (328.5±11.3) N and (269.1±9.6) N separately, demonstrating that the difference was statistically significant (Z=2.865, p=0.004).

CONCLUSIONS

RS placement is an alternative for remediation following a lateral wall breach evidenced by significantly decreased seating torque, screw loosening force, the maximal torque and post-loosening axial pullout compared with OS.

A novel entry point for pedicle screw placement in the thoracic spine

This study was aimed to introduce a novel entry point for pedicle screw fixation in the thoracic spine and compare it with the traditional entry point. A novel entry point was found with the aim of improving accuracy, safety and stability of pedicle screw technique based on anatomical structures of the spine. A total of 76 pieces of normal thoracic CT images at the transverse plane and the thoracic pedicle anatomy of 6 cadaveric specimens were recruited. Transverse pedicle angle (TPA), screw length, screw placement accuracy rate and axial pullout strength of the two different entry point groups were compared. There were significant differences in the TPA, screw length, and the screw placement accuracy rate between the two groups (P<0.05). The maximum axial pullout strength of the novel entry point group was slightly larger than that of the traditional group. However, the difference was not significant (P>0.05). The novel entry point significantly improved the accuracy, stability and safety of pedicle screw placement. With reference to the advantages above, the new entry point can be used for spinal internal fixations in the thoracic spine.

Association between H19 polymorphisms and osteosarcoma risk

OBJECTIVE

The long non-coding RNA (lncRNA) H19, a maternally expressed imprinted gene, has involvement in cancer susceptibility and disease progression. However, the association between H19 polymorphisms and osteosarcoma susceptibility has remained elusive. We designed this case-control study to explore the association between H19 polymorphism and osteosarcoma risk.

PATIENTS AND METHODS

In this study, we genotyped 4 tagger SNPs of the H19 gene in a case-control study including 193 osteosarcoma cases and 393 cancer-free controls.

RESULTS

For the main effect analysis, rs217727 (G>A) was associated with osteosarcoma risk (GA/GG: adjusted OR = 1.51, 95% CI: 1.06-2.17, p = 0.024; AA/GG: adjusted OR = 1.89, 95% CI: 1.23-2.91, p = 0.004; additive model: adjusted OR = 1.35, 95% CI: 1.01-1.80, p = 0.043).

CONCLUSIONS

This finding indicates that rs217727 polymorphism may play a role in genetic susceptibility to the risk of osteosarcoma, which may improve our understanding of the potential contribution of H19 SNPs to cancer pathogenesis.

Strain softening of nano-scale fuzzy interfaces causes Mullins effect in thermoplastic polyurethane

The strain-induced softening of thermoplastic polyurethane elastomers (TPUs), known as the Mullins effect, arises from their multi-phase structure. We used the combination of small- and wide- angle X-ray scattering (SAXS/WAXS) during in situ repeated tensile loading to elucidate the relationship between molecular architecture, nano-strain, and macro-scale mechanical properties. Insights obtained from our analysis highlight the importance of the ‘fuzzy interface’ between the hard and soft regions that governs the structure evolution at nanometre length scales and leads to macroscopic stiffness reduction. We propose a hierarchical Eshelby inclusion model of phase interaction mediated by the ‘fuzzy interface’ that accommodates the nano-strain gradient between hard and soft regions and undergoes tension-induced softening, causing the Mullins effect that becomes apparent in TPUs even at moderate tensile strains.

Mitomycin C induces apoptosis in human epidural scar fibroblasts after surgical decompression for spinal cord injury

Numerous studies have shown that topical application of mitomycin C after surgical decompression effectively reduces scar adhesion. However, the underlying mechanisms remain unclear. In this study, we investigated the effect of mitomycin C on the proliferation and apoptosis of human epidural scar fibroblasts. Human epidural scar fibroblasts were treated with various concentrations of mitomycin C (1, 5, 10, 20, 40 μg/mL) for 12, 24 and 48 hours. Mitomycin C suppressed the growth of these cells in a dose- and time-dependent manner. Mitomycin C upregulated the expression levels of Fas, DR4, DR5, cleaved caspase-8/9, Bax, Bim and cleaved caspase-3 proteins, and it downregulated Bcl-2 and Bcl-xL expression. In addition, inhibitors of caspase-8 and caspase-9 (Z-IETD-FMK and Z-LEHD-FMK, respectively) did not fully inhibit mitomycin C-induced apoptosis. Furthermore, mitomycin C induced endoplasmic reticulum stress by increasing the expression of glucose-regulated protein 78, CAAT/enhancer-binding protein homologous protein (CHOP) and caspase-4 in a dose-dependent manner. Salubrinal significantly inhibited the mitomycin C-induced cell viability loss and apoptosis, and these effects were accompanied by a reduction in CHOP expression. Our results support the hypothesis that mitomycin C induces human epidural scar fibroblast apoptosis, at least in part, via the endoplasmic reticulum stress pathway.

The feasibility study of extradural nerve anastomosis technique for canine bladder reinnervation after spinal cord injury

OBJECTIVE

Intradural nerve anastomosis for bladder innervation has been demonstrated to be useful. However, its clinical application remains limited because of the complex surgery, its complications and extensive bony destruction. The purpose of the current study was to demonstrate the feasibility of extradural spinal root anastomosis for bladder innervation in canines.

METHODS

Ten beagle dogs were used. The length of the extradural segment of the nerve root, upper nerve root outlet (the point at which it emerges from the spinal dura mater) to S2 (dS2), the S3 (dS3) nerve root outlet distance, and the diameters of the extradural spinal roots were measured. The numbers of nerve fibers from L6 to S3 ventral roots were calculated using immunohistochemical staining.

RESULTS

The extradural spinal roots could be divided into a ventral root (VR) and a dorsal root (DR) before the ganglionic enlargement of the dorsal root, and the extradural motor nerve roots situate ventrally to their corresponding sensory nerve roots. The extradural nerve root lengths of S1 and parts of L7 were longer than the corresponding dS2. The numbers of nerve and motor nerve fibers, and the diameters of extradural nerve roots, were gradually descending from L6 to S3.

CONCLUSION

The S1 VRs and parts of the L7 VRs can be extradurally anastomosed to the S2 nerves without tension. A nerve graft was needed for extradural anastomosis of L6 VRs and parts of L7 VRs to S2 VRs. This study demonstrated the feasibility of extradural spinal nerve anastomosis for treating neurogenic bladder in canines.

ER Stress via CHOP Pathway is Involved in FK506-Induced Apoptosis in Rat Fibroblasts

Background/Aims: Hypertrophic scars (HS) formation results from reduced apoptosis and increased proliferation of fibroblasts. Therefore, apoptosis of fibroblasts is a key target for the development of novel therapeutic strategies for HS. Previous reports demonstrated that FK506 could attenuate scar formation in vivo and FK506 could also induce endoplasmic reticulum stress (ER stress). However, the effects of FK506 on ER stress-mediated apoptosis in fibroblasts remain unclear. Methods: Rat skin fibroblasts were used in the study. Cell viability was examined using cell counting Kit-8. Apoptosis was detected by Annexin V/Propidium Iodide Double Staining. Gene silencing was performed using Small Interfering RNAs (siRNAs) or via lentiviral infection. The expression of apoptosis-related proteins was determined via Western blot. Interaction between proteins was explored by co-immunoprecipitation. Results: FK506 significantly reduced cell viability and induced apoptosis in fibroblasts. Interestingly, ER stress was also activated after FK506 treatment. We further demonstrated that FK506-induced apoptosis was mediated by ER stress via activating CHOP, evidenced by decreased apoptosis after inhibition of ER stress using TUDCA or silencing expression of CHOP. Furthermore, Co-immunoprecipitation results indicated that treatment of FK506 induced disassociation of FKBP12.6 from RyR2 and its translocation from ER membrane to cytosol, consequently promoting ER stress-mediated apoptosis. Conclusion: FK506-induced fibroblasts apoptosis was mediated by ER stress via CHOP signaling pathway.

Taurine Reduced Epidural Fibrosis in Rat Models after Laminectomy via Downregulating EGR1

BACKGROUND/AIMS

Epidural fibrosis, a common complication after laminectomy, has been demonstrated to be closely associated with poor surgical outcomes. Previous studies showed that taurine had remarkable anti-fibrotic effects on lung and liver fibrosis. We performed this study to investigate the effects of taurine in rat models of epidural fibrosis after laminectomy and to explore the potential molecular mechanism.

METHODS

Laminectomy was performed on each rat to establish epidural fibrosis model. After taurine treatment, Masson's trichrome and immunohistochemistry staining were used to examine epidural fibrosis. Cell viability was determined using the Cell Counting Kit-8 assay. Annexin V/Propidium Iodide double staining was performed to detect fibroblasts apoptosis. Microarray was adopted to identify significantly changed mRNAs. mRNA expression was measured by qRT-PCR. Lentivirus infection was performed to establish stable knockdown and overexpression cell lines. The expression of fibrosis-related proteins was determined via Western blot.

RESULTS

Taurine treatment markedly reduced laminectomy-induced epidural fibrosis in rat models. However, this effect of taurine was independent on TGF-β/Smad pathway, evidenced by no change in the expression of TGF-β and its receptors. Besides, taurine had almost no effect on cell apoptosis. Interestingly, taurine treatment significantly decreased expression of EGR1 (Early growth response protein 1), an enhancer of fibrosis, both in vivo and in vitro. Furthermore, overexpression of EGR1 increased activation of fibroblasts, while EGR1 knockdown achieved an opposite effect, indicating that EGR1 plays a key role in the inhibitory effect of taurine on TGF-β-induced fibrosis.

CONCLUSIONS

Reduced epidural fibrosis in vivo and decreased activation of fibroblasts in vitro after taurine treatment was mediated by EGR1. Taurine promises to be a potential prevention for epidural fibrosis after laminectomy.

Neuroanatomy and clinical analysis of the cervical sympathetic trunk and longus colli

Anterior cervical surgery is commonly used for cervical vertebral body lesions. However, the structure of blood vessels and nerve tissues along the route of anterior cervical surgery is complex. We aimed to measure the data of the longus colli, the sympathetic trunk and the cervical sympathetic trunk (CST) ganglia in Chinese cadaver specimens. A total of 32 adult cadavers were studied. We delineated the surgical anatomy of the CST. The superior and inferior/cervicothoracic ganglia of the sympathetic trunk consistently appeared. The middle ganglion was observed in 28.1% of the specimens and there were 2 cases of unilateral double middle cervical ganglia. The inferior ganglion was observed in 25.0% of the specimens and the cervicothoracic ganglion was observed in the remaining specimens. The distance between the CST gradually decreased from the top to the bottom, and the distance between the medial edges of the longus colli gradually broadened from the top down. The average angle between the bilateral CST and the midline of the vertebra was 11.2°±1.8° on the left side and 10.3°±1.4° on the right side. The average angle between the medial margins of longus colli of both sides was 11.1°±1.9°. The CST is at high risk when LC muscle is cut transversely or is dragged heavily, especially at the levels of C6 and C7. Awareness of the regional anatomy of the CST could help surgeons to identify and preserve it during anterior cervical surgeries.

Overexpression of Both ERG11 and ABC2 Genes Might Be Responsible for Itraconazole Resistance in Clinical Isolates of Candida krusei

Objective

To study the main molecular mechanisms responsible for itraconazole resistance in clinical isolates of Candida krusei.

Methods

The 14α-demethylases encoded by ERG11 gene in the 16 C.krusei clinical isolates were amplified by polymerase chain reaction (PCR), and their nucleotide sequences were determined to detect point mutations. Meanwhile, ERG11 and efflux transporters (ABC1 and ABC2) genes were determined by quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) for their expression in itraconazole-resistant (R), itraconazole-susceptible dose dependent (SDD) and itraconazole-susceptible (S) C.krusei at the mRNA level.

Results

We found 7-point mutations in ERG11 gene of all the C.krusei clinical isolates, including 6 synonymous mutations and 1 missense mutation (C44T). However, the missense mutation was found in the three groups. The mRNA levels of ERG11 gene in itraconazole-resistant isolates showed higher expression compared with itraconazole-susceptible dose dependent and itraconazole-susceptible ones (P = 0.015 and P = 0.002 respectively). ABC2 gene mRNA levels in itraconazole-resistant group was significantly higher than the other two groups, and the levels of their expression in the isolates appeared to increase with the decrease of susceptibility to itraconazole (P = 0.007 in SDD compared with S, P = 0.016 in SDD with R, and P<0.001 in S with R respectively). While ABC1 gene presented lower expression in itraconazole resistant strains. However, the mRNA levels of ERG11, ABC1 and ABC2 in a C.krusei (CK10) resistant to both itraconazole and voriconazole were expressed highest in all the itraconazole-resistant isolates.

Conclusions

There are ERG11 gene polymorphisms in clinical isolates of C.krusei. ERG11 gene mutations may not be involved in the development of itraconazole resistance in C.krusei. ERG11 and ABC2 overexpression might be responsible for the acquired itraconazole resistance of these clinical isolates.

An MRI-based feasibility study of unilateral percutaneous vertebroplasty

Background

Percutaneous vertebroplasty (PVP) has been demonstrated to be effective in the treatment of osteoporotic fracture. The bilateral pedicular approach is the most frequently used method. However, unilateral PVP is becoming increasingly more attractive for surgeons because of its numerous benefits, including lower radiation exposure, less tissue injury, and less bone cement leakage. The purpose of this study was to investigate the anatomical feasibility of unilateral PVP by exploring the differences in the puncture success rate of the unilateral pedicular approach among different lumbar segments, between men and women, and between the left and right sides.

Methods

Punctures were simulated on magnetic resonance imaging scans of 200 patients (100 men, 100 women) at a maximum angle via a pedicular approach. The distance between the entry point and the midline of the vertebral body, the maximum puncture angle, the puncture success value, and the puncture success rate were measured and compared among different lumbar levels, between the two sexes, and between the left and right sides.

Results

The maximum puncture distance between the entry point and the midline gradually increased from L1 to L5, and the maximum puncture angle showed the same tendency from L1 to L5. The puncture success values for L3 and L4 were higher than those for the other lumbar levels (L1, 31.53 ± 34.45; L2, 42.15 ± 28.06; L3, 56.21 ± 18.30; L4, 56.20 ± 12.93; and L5, 48.01 ± 6.88). The puncture success rates varied from 69.5 to 98.0 % among the different lumbar levels; L3 and L4 were the two highest (L3, 95.5 %; L4, 98.0 %). There were significant differences in these measurements between men and women and between the left and right sides.

Conclusions

PVP with the unilateral puncture approach appears more likely to succeed at L3 to L5 than at L1 and L2. The unilateral approach might be more suitable for men than women at levels other than L5. Additionally, the left pedicular approach might be optimal for unilateral PVP procedures.

Application of Near Infrared Spectroscopy Coupled with Fluidized Bed Enrichment and Chemometrics to Detect Low Concentration of β-Naphthalenesulfonic Acid

A fluidized bed enrichment technique was developed to improve sensitivity of near infrared (NIR) spectroscopy with features of rapidness and large volume solution. D301 resin was used as an adsorption material to preconcentrate β-naphthalenesulfonic acid in solutions in a concentration range of 2.0-100.0 μg/mL, and NIR spectra were measured directly relative to the β-naphthalenesulfonic acid adsorbed on the material. An improved partial least squares (PLS) model was attained with the aid of multiplicative scatter correction pretreatment and stability competitive adaptive reweighted sampling wavenumber selection method. The root mean square error of cross validation was 1.87 μg/mL at PLS factor of 7. An independent test set was used to assess the model, with the relative error (RE) in an acceptable range of 0.46 to 10.03% and mean RE of 3.72%. This study confirmed the viability of the proposed method for the measurement of a low content of β-naphthalenesulfonic acid in water.

X-ray Study of Human Dental Tissues Affected by Erythroblastosis Fetalis

Numerous diseases are known to cause microstructural alteration of dental tissues structure. One type in particular is associated with neonatal jaundice and circulation of bilirubin in blood at high concentration due to increased hemolysis in conditions such as erythroblastosis fetalis, septicemia, biliary atresia, and other causes of hyperbilirubinemia. In those conditions, the products of the catabolism of hemoglobin end up deposited in various tissues, including teeth, where they can present clinically as visibly stained brown/green teeth. There is almost no information on the nature or extent of the structural changes taking place in these conditions. Here, advanced nondestructive wide-angle synchrotron X-ray scattering techniques combined with scanning microscopy methods were used to investigate for the first time the ultrastructure of the dental hard tissues in an archival case of intrinsically pigmented green teeth. Despite no obvious elemental variation across the pigmented tissue region, the high-resolution crystallographic properties probed by wide-angle synchrotron X-ray scattering revealed an ultrastructural variation (orientation, particle size, and lattice parameter of hydroxyapatite crystallites) associated with a pigmentation line in dentine and with a distinct neonatal line in enamel.

Tacrolimus reduces scar formation and promotes sciatic nerve regeneration

A sciatic nerve transection and repair model was established in Sprague-Dawley rats by transecting the tendon of obturator internus muscle in the greater sciatic foramen and suturing with nylon sutures. The models were treated with tacrolimus gavage (4 mg/kg per day) for 0, 2, 4 and 6 weeks. Specimens were harvested at 6 weeks of intragastric administration. Masson staining revealed that the collagen fiber content and scar area in the nerve anastomosis of the sciatic nerve injury rats were significantly reduced after tacrolimus administration. Hematoxylin-eosin staining showed that tacrolimus significantly increased myelinated nerve fiber density, average axon diameter and myelin sheath thickness. Intragastric administration of tacrolimus also led to a significant increase in the recovery rate of gastrocnemius muscle wet weight and the sciatic functional index after sciatic nerve injury. The above indices were most significantly improved at 6 weeks after of tacrolimus gavage. The myelinated nerve fiber density in the nerve anastomosis and the sciatic nerve functions had a significant negative correlation with the scar area, as detected by Spearman’s rank correlation analysis. These findings indicate that tacrolimus can promote peripheral nerve regeneration and accelerate the recovery of neurological function through the reduction of scar formation.

Rapid identification of spinal ventral and dorsal roots using a quartz crystal microbalance

The fast and accurate identification of nerve tracts is critical for successful nerve anastomosis. Taking advantage of differences in acetylcholinesterase content between the spinal ventral and dorsal roots, we developed a novel quartz crystal microbalance method to distinguish between these nerves based on acetylcholinesterase antibody reactivity. The acetylcholinesterase antibody was immobilized on the electrode surface of a quartz crystal microbalance and reacted with the acetylcholinesterase in sample solution. The formed antigen and antibody complexes added to the mass of the electrode inducing a change in frequency of the electrode. The spinal ventral and dorsal roots were distinguished by the change in frequency. The ventral and dorsal roots were cut into 1 to 2-mm long segments and then soaked in 250 μL PBS. Acetylcholinesterase antibody was immobilized on the quartz crystal microbalance gold electrode surface. The results revealed that in 10 minutes, both spinal ventral and dorsal roots induced a frequency change; however, the frequency change induced by the ventral roots was notably higher than that induced by the dorsal roots. No change was induced by bovine serum albumin or PBS. These results clearly demonstrate that a quartz crystal microbalance sensor can be used as a rapid, highly sensitive and accurate detection tool for the quick identification of spinal nerve roots intraoperatively.

Potential risk of mitomycin C at high concentrations on peripheral nerve structure

Although the local application of mitomycin C may prevent epidural adhesion after laminectomy, mitomycin C can induce neurotoxicity in optic and acoustic nerves at high concentrations. To determine the safe concentration range for mitomycin C, cotton pads soaked with mitomycin C at different concentrations (0.1, 0.3, 0.5, and 0.7 mg/mL) were immediately applied for 5 minutes to the operation area of rats that had undergone laminectomy at L₁. Rat sciatic nerves, instead of dorsal nerves, were used in this study. The results showed that mitomycin C at 0.1-0.5 mg/mL did not damage the structure and function of the sciatic nerve, while at 0.7 mg/mL, mitomycin C significantly reduced the thickness of the sciatic nerve myelin sheath compared with lower concentrations, though no functional change was found. These experimental findings indicate that the local application of mitomycin C at low concentrations is safe to prevent scar adhesion following laminectomy, but that mitomycin C at high concentrations (> 0.7 mg/mL) has potential safety risks to peripheral nerve structures.

[Plasma microRNA profile in immune thrombocytopenia: screening and verification]

OBJECTIVE

To screen the plasma microRNA (miRNA) profile of immune thrombocytopenia (ITP) patients.

METHODS

Agilent 19.0 miRNA microarray was used to detect the expression profile of miRNA in plasma from 25 ITP patients and 20 healthy controls from June 2012 to September 2013. The software programs of TargetScan and miRanda were used for predicting target genes associated with differential miRNA. Then gene ontology (GO) and pathway analysis were performed to explore the genes and pathways involved in the pathogenesis of ITP. And differential miRNA was validated by real-time quantitative polymerase chain reaction (PCR).

RESULTS

A genome-wide miRNA array revealed 29 differential miRNAs in the plasma samples of ITP patients including 15 up-regulated and 14 down-regulated miRNA. A total of 608 potential genes were predicted by TargetScan and miRanda.GO result showed that there were 475 (78.12%), 491(80.76%) and 533 (87.66%) genes respectively involved in biological process, molecular function and cellular component.Enrichment test showed 9 GO terms had significant difference (P < 0.05). Pathway analysis showed that 157 pathways were associated with 608 genes.Enrichment test showed 25 pathways had significant difference (P < 0.05). As revealed by real-time PCR, the expressions of miRNA4778-5p and miRNA4800-5p became obviously up-regulated while those of miRNA4707-5p, miRNA4721, miRNA3620-3p and miRNA378i decreased (all P < 0.05). The results agreed with those of microarray.

CONCLUSIONS

The plasma differential miRNA profiles are identified in ITP patients. And miRNA is involved in calcium signaling pathway and T cell receptor signaling pathway may be associated with ITP pathogenesis.

Position and complications of pedicle screw insertion with or without image-navigation techniques in the thoracolumbar spine: a meta-analysis of comparative studies

Computer-navigated pedicle screw insertion is applied to the thoracic and lumbar spine to attain high insertion accuracy and a low rate of screw-related complications. However, some in vivo and in vitro studies have shown that no advantages are gained with the use of navigation techniques compared to conventional techniques. Additionally, inconsistent conclusions have been drawn in various studies due to different population characteristics and methods used to assess the accuracy of screw placement. Moreover, it is not clear whether pedicle screw insertion with navigation techniques decreases the incidence of screw-related complications. Therefore, this study was sought to perform a meta-analysis of all available prospective evidence regarding pedicle screw insertion with or without navigation techniques in human thoracic and lumbar spine. We considered in vivo comparative studies that assessed the results of pedicle screw placement with or without navigation techniques. PubMed, Ovid MEDLINE and EMBASE databases were searched. Three published randomized controlled trials (RCTs) and nine retrospective comparative studies met the inclusion criteria. These studies included a total of 732 patients in whom 4,953 screws were inserted. In conclusion, accuracy of the position of grade I, II, III and IV screws and complication rate related to pedicle screw placement were significantly increased when navigation techniques were used in comparison to conventional techniques. Future research in this area should include RCTs with well-planned methodology to limit bias and report on validated, patient-based outcome measures.

Resveratrol inhibits the phosphatidylinositide 3-kinase/protein kinase B/mammalian target of rapamycin signaling pathway in the human chronic myeloid leukemia K562 cell line

Resveratrol inhibits the initiation, promotion and progression of tumors, however, the mechanism by which resveratrol inhibits the proliferation of the human chronic myeloid leukemia K562 cell line remains unclear. The present study was conducted to investigate the effect of resveratrol on the activation of the phosphatidylinositide 3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling cascade in K562 cells. Resveratrol showed significant cytotoxic effects and induced apoptosis in K562 cells in a dose- and time-dependent manner. In addition, resveratrol attenuated the phosphorylation of PI3K, Akt and mTOR in the K562 cells. Furthermore, the selected inhibitors of PI3K (LY294002), Akt (SH-6) and mTOR (rapamycin) enhanced the effects of resveratrol in K562 cells. In addition, cyclin D1 levels were found to decrease and the activation of caspase-3 was observed. Resveratrol was also found to significantly attenuate the phosphorylation of the downstream molecules, p70S6K and 4EBP1. These results suggested that the downregulation of the PI3K/Akt/mTOR signaling cascades may be a crucial mediator in the inhibition of proliferation and induction of apoptosis by resveratrol in K562 cells.

[Construction, expression and functional detection of fusion gene of CD80 extracellular region and anti-human CD33 scFv]

OBJECTIVE

To construct and express the CD80 extracellular region-anti-human CD33 single chain fragment of variable region (ExCD80-CD33scFv) fusion gene, and detect the biological activity of the fusion protein.

METHODS

Extracellular region of CD80 (ExCD80) was amplified and then linked with anti-CD33scFv using 403Aa-427Aa (hydrophilic fragments) in domain III of human serum albumin (HAS) as interlinker. The recombinant fusion gene was subcloned into the prokaryotic expression vector PET22b(+) and expressed in E.coli Rosetta (DE3) after induction by IPTG. The purified fusion protein was obtained after a series of purification steps including cell lysis, inclusion body solubilization, Ni(2+); metal affinity chromatography and protein refolding. The biological activity of the fusion protein was detected with indirect immunofluorescence technique.

RESULTS

The ExCD80 (633bp) was amplified by PCR and 403aa-427aa from domain III of HAS as interlinker was synthesized correctly. SDS-PAGE and Western blotting demonstrated that ExCD80-CD33scFv fusion gene expression vector was successfully constructed and expressed in E.coli Rosetta (DE3). The relative molecular mass (Mr;) of the fusion protein was 55 000, which has human CD33-binding specificity after renaturation as shown by indirect immunofluorescence technique.

CONCLUSION

Recombinant ExCD80-CD33scFv fusion gene was successfully constructed and expressed in E.coli Rosetta (DE3), which could provide a foundation for the future target therapy to the myeloid leukemia.

A case of hypereosinophilic syndrome presenting with multiorgan thromboses associated with intestinal obstruction

Idiopathic hypereosinophilic syndrome (HES) is a disease characterized by persistent hypereosinophilia (>1.5×109/L) for more than 6 months in the absence of other causes of reactive eosinophilia. Patients with HES presenting with multiorgan thromboses are rare. Herein we report a 57-year-old man with HES who presented with deep venous thrombosis of the lower extremities, portal thrombosis, pulmonary embolism, and mesenteric venous thrombosis, which led to intestinal obstruction.

Conflict of interest:None declared.

An acetylcholinesterase antibody-based quartz crystal microbalance for the rapid identification of spinal ventral and dorsal roots

Differences in the levels of acetylcholinesterase (AChE) in ventral and dorsal spinal roots can be used to differentiate the spinal nerves. Although many methods are available to assay AChE, a rapid and sensitive method has not been previously developed. Here, we describe an antibody-based quartz crystal microbalance (QCM) assay and its application for the quantification of AChE in the solutions of ventral and dorsal spinal roots. The frequency variation of the QCM device corresponds to the level of AChE over a wide dynamic range (0.5-10 µg/ml), which is comparable to the response range of the ELISA method. The frequency shift caused by the ventral roots is 3-fold greater than that caused by the dorsal roots. The antibody-based QCM sensor was stable across many successive replicate samples, and the method required less than 10 min, including the AChE extraction and analysis steps. This method is a rapid and convenient means for the quantification of AChE in biological samples and may be applicable for distinguishing the ventral and dorsal roots during surgical operations.

Inhibition of epidural fibrosis after microendoscopic discectomy with topical application of mitomycin C: a randomized, controlled, double-blind trial

OBJECT

The authors conducted a study to evaluate the effects and the safety of locally applied mitomycin C (MMC) on epidural fibrosis after microendoscopic discectomy (MED).

METHODS

Seventy-five patients undergoing single-level unilateral MED for lumbar disc herniation were randomly assigned to receive cotton wool impregnated with either 0.5 mg/ml MMC or saline applied at the site of discectomy for 5 minutes. Outcome measures included degrees of pain severity, functional disability, physical symptoms, and quantitative evaluation of postoperative epidural fibrosis shown on follow-up lumbar contrast-enhanced MRI.

RESULTS

Sixty-two patients completed the follow-up. Neither serious drug adverse effects nor clinically significant laboratory adverse effects were observed. Patients in both groups showed similar clinical recoveries postoperatively. A statistically significant difference (p < 0.05) between the 2 treatments was shown in a quantitative evaluation of postoperative MRI-documented epidural fibrosis in the MMC group and the saline group using a modified grading system. The mean cross-sectional areas of epidural fibrosis were 7.32-70.06 mm(2) in the MMC group and 22.94-90.48 mm(2) in the saline group. The epidural fibrosis index ranged from 0.0296 to 0.3267 in the MMC group and from 0.1191 to 0.3483 in the saline group. A significant difference was also observed using the Ross grading system to evaluate postoperative MR images.

CONCLUSIONS

Although no benefit was observed clinically, the authors observed a notable reduction of epidural fibrosis after MED radiologically, with 0.5 mg/ml MMC locally applied and no clinical side effects.

Effect of FK506 in reducing scar formation by inducing fibroblast apoptosis after sciatic nerve injury in rats

We previously demonstrated that FK506, a generally applied immunosuppressant in organ transplantation, could promote peripheral nerve regeneration through reducing scar formation. However, little is known about how FK506 reduces scar formation. Herein we investigated the influence of FK506 on fibroblast proliferation and its correlation with scar formation after sciatic nerve injury in rats, and further explored the effect of FK506 on fibroblast proliferation and apoptosis in vitro. Masson staining and immunohistochemistry revealed that scar area and fibroblast number in the nerve anastomosis of sciatic nerve-injured rats were significantly reduced after FK506 administration. The scar area had a significant positive correlation with the fibroblast number, as detected by linear correlation analysis. CCK-8 assay and flow cytometry indicated that FK506 also inhibited proliferation and induced apoptosis of fibroblasts in vitro. It was primarily phosphorylation of JNK and ERK that were activated during the apoptosis of fibroblast. Pretreatment of cells with JNK inhibitor, SP600125, or ERK inhibitor, PD98059, could inhibit FK506-induced fibroblast apoptosis, respectively. Moreover, simultaneous application of both inhibitors had additive roles in cell protection from apoptosis. These results suggest that FK506-induced fibroblast apoptosis contributes to the suppression of fibroblast proliferation and then results in the reduction of scar formation in sciatic nerve-injured rat, and that JNK and ERK are involved in FK506-induced fibroblast apoptosis.

Micturition reflex arc reconstruction including sensory and motor nerves after spinal cord injury: urodynamic and electrophysiological responses

OBJECTIVE

To evaluate artificial reflex arcs for micturition using urodynamics and electrophysiological recordings.

DESIGN

Sixteen beagles were equally and randomly divided into two groups.

METHODS

In group A, anastomosis of the proximal end of the left L7 ventral root (VR) and distal end of the left S2 VR was performed, as well as anastomosis of the L7 dorsal root (DR) and S2 DR to reconstruct the sensory and the motor function of the bladder. In group B the proximal end of the left L7 VR and the distal end of the left S2 VR were anastomosed, while the left L7 DR was kept intact to reconstruct the motor function of the bladder. Outcome measures included electrophysiological testing and the urodynamic measures. In addition, we also monitored urinary infection rates.

RESULTS

Stimulation to the left S2 DR in groups A and B both elevated the bladder pressure before and after the spinal lower motor neuron lesion. Single stimulation of the two groups both elicited evoked action potentials. Urinary infections occurred in group A (three occurrences) and in group B (eight occurrences) during the 3 months after the spinal lower motor neuron lesion.

CONCLUSION

Data showed that both reconstructive methods could induce bladder micturition and evoked action potentials. However, in group A the micturition response was better and the urinary infection rates were lower after the spinal lower motor neuron lesion. Thus, the artificial physiological reflex arc reconstruction method used in group A, with sensory input above the lesion, might provide a better alternative in clinical practice.

[Efficacy and safety of two different low-dose rituximab regimens for Chinese adult patients with immune thrombocytopenia]

OBJECTIVE

To compare the efficacy of two different regimens of low doses rituximab for the treatment of adult patients with immune thrombocytopenia (ITP).

METHODS

Fifty-one patients were enrolled in this study and was non-randomly assigned to receive 100 mg rituximab weekly for 4 weeks (group A, 31 cases) or a single dose of 375 mg/m2 rituximab (group B, 20 cases).

RESULTS

For group A: Overall and complete response (OR and CR) rates were 58% and 29% , respectively. In responders, the median time to response was 42 (10 -101) days, with a median follow-up time of 15 (10 - 16) months, 3 of 18 responders (17%) relapsed. For group B: OR and CR rates were 50% and 35% , respectively. In responders, the median time to response was 35 (18 - 108) days, with a median follow-up time of 13 (6 -17) months, 1 of 9 responders (11%) relapsed. No significant difference in the OR, CR, the relapse rate and relapse free survival was observed in patients between the two groups.

CONCLUSION

The low dose rituximab regimen (100 mg weekly for 4 weeks or a single close of 375 mg/m2) may be a useful alternative therapy in patients with ITP.

Confocal imaging reveals three-dimensional fine structure difference between ventral and dorsal nerve roots

Peripheral nerve injury repair is one of the most challenging problems in neurosurgery, partially due to lack of knowledge of three-dimensional (3-D) fine structure and organization of peripheral nerves. In this paper, we explored the structures of nerve fibers in ventral and dorsal nerves with a laser scanning confocal microscopy. Thick tissue staining results suggested that nerve fibers have a different 3-D structure in ventral and dorsal nerves, and reconstruction from serial sectioning images showed that in ventral nerves the nerve fibers travel in a winding form, while in dorsal nerves, the nerve fibers form in a parallel cable pattern. These structural differences could help surgeons to differentiate ventral and dorsal nerves in peripheral nerve injury repair, and also facilitate scientists to get a deeper understanding about nerve fiber organization.