Takane Suzuki

Semaphorin7A Promotion of Tumoral Growth and Metastasis in Human Oral Cancer by Regulation of G1 Cell Cycle and Matrix Metalloproteases: Possible Contribution to Tumoral Angiogenesis.

Background Semaphorins (SEMAs) consist of a large family of secreted and membrane-anchored proteins that are important in neuronal pathfinding and axon guidance in selected areas of the developing nervous system. Of them, SEMA7A has been reported to have a chemotactic activity in neurogenesis and to be an immunomodulator; however, little is known about the relevance of SEMA7A in the behaviors of oral squamous cell carcinoma (OSCC). Methods We evaluated SEMA7A expression in OSCC-derived cell lines and primary OSCC samples using quantitative reverse transcriptase-polymerase chain reaction, immunoblotting, and semiquantitative immunohistochemistry (sq-IHC). In addition, SEMA7A knockdown cells (shSEMA7A cells) were used for functional experiments, including cellular proliferation, invasiveness, and migration assays. We also analyzed the clinical correlation between SEMA7A status and clinical behaviors in patients with OSCC. Results SEMA7A mRNA and protein were up-regulated significantly (P<0.05) in OSCC-derived cell lines compared with human normal oral keratinocytes. The shSEMA7A cells showed decreased cellular growth by cell-cycle arrest at the G1 phase, resulting from up-regulation of cyclin-dependent kinase inhibitors (p21Cip1 and p27Kip1) and down-regulation of cyclins (cyclin D1, cyclin E) and cyclin-dependent kinases (CDK2, CDK4, and CDK6); and decreased invasiveness and migration activities by reduced secretion of matrix metalloproteases (MMPs) (MMP-2, proMMP-2, pro-MMP-9), and expression of membrane type 1- MMP (MT1-MMP). We also found inactivation of the extracellular regulated kinase 1/2 and AKT pathways, an upstream molecule of cell-cycle arrest at the G1 phase, and reduced secretion of MMPs in shSEMA7A cells. sq-IHC showed that SEMA7A expression in the primary OSCCs was significantly (P = 0.001) greater than that in normal counterparts and was correlated with primary tumoral size (P = 0.0254) and regional lymph node metastasis (P = 0.0002). Conclusion Our data provide evidence for an essential role of SEMA7A in tumoral growth and metastasis in OSCC and indicated that SEMA7A may play a potential diagnostic/therapeutic target for use in patients with OSCC.

One, two-, and three-level instrumented posterolateral fusion of the lumbar spine with a local bone graft: a prospective study with a 2-year follow-up.

Study Design. Prospective trial. Objective. To examine the difference in bone union and clinical results after one-, two-, and three-level instrumented posterolateral fusion surgery using a local bone graft. Summary of Background Data. The iliac crest bone graft technique for lumbar posterolateral fusion surgery is widely used; however, donor site problems such as pain and sensory disturbance have been reported. Local bone has been used for fusion surgery; however, its reliability as a graft for multiple segments has not been fully reported. Methods. One hundred twenty-two patients diagnosed with degenerated spondylolisthesis were divided into three groups [spondylolisthesis at 1 level (n = 42), at 2 levels (n = 40), and at 3 levels (n = 40)]. All patients underwent decompression and instrumented posterolateral fusion with a local bone graft. The amount of bone graft, proportion of patients with (rate) and duration of bone union, Visual Analog Scale (VAS) score, Japanese Orthopedic Association Score (JOAS), and Oswestry Disability Index (ODI) were evaluated before and 2 years after therapy. Results. VAS score, JOA score, and ODI were not significantly different among the three groups before and after surgery (P > 0.05). Average amount of local bone graft used for one segment significantly decreased in proportion to the number of fusion levels (P < 0.05). The rate of bone union was 88% in the one-level group, 85% in the two-level group, and 62.5% in the three-level group, which was significantly lower than that in the one- and two-level groups (P < 0.05). Conclusion. If one- and two-level posterolateral fusion were performed, the local bone graft technique provides a good and uniform bone union rate; however, for three-level fusion poor results were obtained because of an insufficient amount of local bone.

Perioperative Complications in 155 Patients Who Underwent Oblique Lateral Interbody Fusion Surgery: Perspectives and Indications From a Retrospective, Multicenter Survey.

Study Design. A retrospective multicenter survey. Objective. To investigate the perioperative complications of oblique lateral interbody fusion (OLIF) surgery. Summary of Background Data. OLIF has been widely performed to achieve minimally invasive, rigid lumbar lateral interbody fusion. The associated perioperative complications are not yet well described. Methods. The participants were patients who underwent OLIF surgery under the diagnosis of degenerative lumbar diseases between April 2013 and May 2015 at 11 affiliated medical institutions. The collected data were classified into intraoperative and early-stage postoperative (⩽1 mo) complications. The intraoperative complications were then subcategorized into organ damage (neural, vertebral, vascular, and others) and other complications, mainly related to instrumental failure. The collected data were also divided and analyzed based on whether the surgeon was certified to perform the surgery and the incidence of complications in the early (April 2013–March 2014) and late stages (April 2014–May 2015) of OLIF introduction. Results. In the 155 included patients, 75 complications were reported (incidence rate, 48.3%). The most common complication was endplate fracture/subsidence (18.7%), followed by transient psoas weakness and thigh numbness (13.5%) and segmental artery injury (2.6%). Almost all these complications were transient, except for three patients who had permanent damage: one had ureteral injury and two had neurological injury. Postoperative complications included surgical site infection (1.9%) and reoperation (1.9%). Whether the primary operator was experienced did not affect the incidence of complications. Regarding the introductory stage, the incidence of complications was 50% in the early stage and 38% in the late stage. Conclusion. The overall incidence of perioperative complications of OLIF surgery reached 48.3%, of which only 1.9% resulted in permanent damage. Our analysis based on surgeon experience indicated that the OLIF procedure could be performed without increasing incidence of complications, under the guidance of experienced supervisors. Level of Evidence: 3

Vein Wrapping for Chronic Nerve Constriction Injury in a Rat Model: Study Showing Increases in Vegf and Hgf Production and Prevention of Pain-associated Behaviors and Nerve Damage

BACKGROUND Although efficacious clinical results have been reported after vein wrapping for the treatment of recurrent compressive neuropathy, the mechanism of nerve protection remains uncertain. METHODS Eight-week-old male Wistar rats (n = 90) were randomly divided into three groups: sham procedure, chronic constriction injury, and chronic constriction injury plus vein wrapping. Mechanical withdrawal thresholds and walking patterns were measured with use of von Frey filaments and the CatWalk system, respectively. We investigated L4-L5 dorsal root ganglia immunohistochemically at fourteen days postsurgery and sciatic nerves histologically at fourteen days and again five months postsurgery. Concentrations of several sciatic neurotrophic factors in the ligated sciatic nerves were quantified with use of ELISA (enzyme-linked immunosorbent assay). RESULTS In behavioral tests, the rats in which the chronic constriction injury had been followed by vein wrapping displayed significantly greater pain responses than the sham group, and the group with untreated chronic constriction injury showed greater pain responses than the vein-wrapping group (both p < 0.05). Immunoreactive markers of inflammation and nerve damage, calcitonin gene-related peptide (CGRP) and activating transcription factor-3 (ATF3), were upregulated in dorsal root ganglion neurons in the constriction-injury and vein-wrapping groups compared with those in the sham group, with greater upregulation in the constriction-injury group than in the vein-wrapping group (both p < 0.01). Histologic observation showed marked nerve degeneration and scar tissue formation around the sciatic nerve in the constriction-injury group, but these effects were prevented to some extent in the vein-wrapping group. Vascular endothelial growth factor (VEGF) levels at one and three days postsurgery and hepatocyte growth factor (HGF) levels at three, seven, fourteen, and twenty-eight days postsurgery were significantly higher in the vein-wrapping group than in the other groups (p < 0.05). CONCLUSIONS Vein wrapping decreased pain-associated behavior and nerve damage caused by chronic constriction injury. VEGF and HGF produced in response to vein grafts may play a mechanistic role. CLINICAL RELEVANCE These findings may lead to development of new therapies employing growth factors, with or without other materials, that simulate vein wrapping.

The effect of Anti-NGF receptor (p75 Neurotrophin Receptor) antibodies on nociceptive behavior and activation of spinal microglia in the rat brachial plexus avulsion model.

Study Design. We measured the response of the behavior and spinal glial activation to anti-nerve growth factor receptor (p75 neurotrophin receptor [p75NTR]) antibodies in the rat brachial plexus avulsion (BPA) model. Objective. The aim of this study was to investigate the effect of anti-p75NTR antibodies on nociceptive behavior and activation of spinal microglia in the rat BPA model. Summary of Background Data. Tanezumab (anti-nerve growth factor antibody) treatment is associated with pain reduction and improvement in function, but with several complications. Methods. Thirty male Wistar rats were used. In the BPA group, the C8–T1 roots were avulsed from the spinal cord with forceps at the lower trunk level and 10 &mgr;L of saline was applied locally (n = 10). In the anti-p75NTR group, the C8–T1 roots were avulsed and 10 &mgr;L of anti-p75NTR antibody was applied locally (n = 10). In a sham-operated group, the lower trunk was simply exposed (n = 10). Mechanical hyperalgesia and pain-induced walking patterns were measured using von Frey filaments (Stoelting, Wood Dale, IL) and the CatWalk gait analysis (Noldus Information Technology, the Netherlands) system every third day for 3 weeks. Activation of astrocytes and microglia was immunohistochemically examined in the spinal cord using anti-glial fibrillary acidic protein (GFAP) and anti-Iba1 antibodies both 7 and 21 days after surgery. Results. Animals in the BPA group displayed significant mechanical hyperalgesia that continued through day 21 compared with animals in the sham-operated group, and mechanical hyperalgesia in the anti-p75NTR group was significantly improved 6 days after the operation. Regarding pain-induced gait analysis via CatWalk, animals in the BPA group displayed a significantly greater pain-like gait pattern than the p75 group for up to 3 weeks. Levels of GFAP-immunoreactive astrocytes and Iba1-immunoreactive microglia in the anti-p75NTR group were significantly reduced compared with the BPA group. Conclusion. Our results suggest that p75NTR contributes to neuropathic pain associated with BPA, and that inhibition of p75NTR reduces neuropathic pain. Level of Evidence: N/A

Activation of Astrocytes and Microglia in the C3–T4 Dorsal Horn by Lower Trunk Avulsion in a Rat Model of Neuropathic Pain

PURPOSE Brachial plexus pain is thought to be generated not by avulsed roots but rather by nonavulsed roots, because avulsed roots could not transmit action potentials to central nerves. The aim of this study was to evaluate pain-related behavior and the extent of glial activation in a model of brachial plexus avulsion (BPA). METHODS We used 24 male Wistar rats. For rats in the BPA group, the C8-T1 roots were avulsed from the spinal cord at the level of the lower trunk (n = 10). Rats in a sham-surgery group had a similar surgery without the root avulsion (n = 7). Rats in an untreated group had no surgery (n = 7). Mechanical hyperalgesia of the forelimb plantar surfaces corresponding to C6 and C7 dermatomes was evaluated using a Semmes-Weinstein monofilament test every third day for 3 weeks (n = 15). Activation of astrocytes and microglia was examined immunohistochemically using anti-glia fibrillary acidic protein and anti-Iba1 antibodies 3 days after surgery (n = 9). RESULTS When compared with rats in the sham-surgery and naive control groups, rats in the BPA group displayed significant mechanical hyperalgesia in the dermatome innervated by uninjured nerves both ipsilaterally and contralaterally and continuing through day 21. Iba1-immunoreactive microglia and glia fibrillary acidic protein-immunoreactive astrocytes were significantly activated on the ipsilateral side in the BPA group from levels C3 to T3 compared with the sham-surgery and untreated groups of rats. CONCLUSIONS Activation of glia at uninjured levels of the dorsal horn may facilitate pain transmission following BPA injury. Consequently, spared spinal glial cells may represent therapeutic targets for treatment of pain related to BPA injury. CLINICAL RELEVANCE Our findings may indicate why neuropathic pain is so frequent and intense following BPA injury.

Lower Lumbar Segmental Arteries Can Intersect Over the Intervertebral Disc in the Oblique Lateral Interbody Fusion Approach With a Risk for Arterial Injury: Radiological Analysis of Lumbar Segmental Arteries by Using Magnetic Resonance Imaging.

Study Design. A retrospective radiological study on vascular anatomy. Objective. The aim of this study was to evaluate the anatomical and radiological features of lumbar segmental arteries with respect to the surgical field of the oblique lateral interbody fusion (OLIF) approach by using magnetic resonance imaging (MRI). Summary of Background Data. OLIF surgery restores disc height and enables indirect decompression of narrowed spinal canals through an oblique lateral approach to the spine, by using a specially designed retractor. In a minimal surgical field, injuring segmental arteries can cause massive hemorrhage. Methods. We reviewed 272 lumbar MRIs. In the sagittal images, the intersection of one-third of the anterior and median lines of the intervertebral disc (IVD) was considered the center of the virtually installed OLIF retractor. The cephalad/caudal distances from the center and branch angles of segmental arteries to the longitudinal axes of the aorta were measured to determine whether the segmental arteries run into the surgical area. Statistical significance was set at P < 0.05. Results. The branch angles of segmental arteries were significantly acute (⩽90°) in L1–L3 arteries and significantly blunt (>90°) in L4 and L5 arteries. The average distance to the center of the caudal adjacent IVD was significantly larger, and there were generally low possibilities for the existence of segmental arteries below half of the vertebral height, where the surgeons can install fixation pins with ease and safety. Among the lumbar segmental arteries, L5 showed specific characteristics with significant deviation, a four times (4.1% vs. L1–L3 segmental arteries) higher adjacency rate, and a two-fifth (38.6% vs. 100%) lower existence rate. Conclusion. Segmental arteries can be involved in the surgical field of OLIF especially in the lower lumbar spine level of L4 and L5 arteries, which can directly run across IVDs. L5 segmental arteries can also be iliolumbar arteries that have an abnormal trajectory by nature. Level of Evidence: 4

Characteristics of low back pain in adolescent patients with early-stage spondylolysis evaluated using a detailed visual analogue scale.

Study Design. Retrospective comparative cohort study. Objective. To elucidate the characteristics of low back pain (LBP) in adolescent patients with early-stage spondylolysis (ESS). Summary of Background Data. ESS is a common cause of acute LBP in adolescents. When treating patients with ESS, early diagnosis is important; however, early diagnosis is difficult without magnetic resonance imaging. Methods. Adolescent patients (n = 77) with acute LBP showing no pathological findings on plain radiography were included (<1 m after onset). Patients were divided into ESS and nonspecific LBP (NS-LBP) groups by conducting magnetic resonance imaging; patients showing no pathological findings that explain the cause of LBP were classified as NS-LBP. LBP was evaluated using a traditional visual analogue scale (VAS; 0–10 cm), Oswestry Disability Index, and a detailed VAS scoring system in which pain is independently evaluated in 3 different postural situations (in motion, standing, and sitting); the values were compared between the 2 groups. Results. Of 77 patients, 41 (mean age: 14.6 yr; 33 adolescent boys/8 adolescent girls) had ESS and 36 (mean age: 14.3 yr; 20 adolescent boys/16 adolescent girls) were considered to have NS-LBP. Respective traditional VAS and Oswestry Disability Index scores were 4.9, 16.1 in the ESS group, and 6.2, 26.3 in the NS-LBP group. Both scores were significantly higher in the NS-LBP group. The results of the detailed VAS revealed that the ESS group showed significantly greater pain intensity while in motion than while standing or sitting (4.2, 2.0, and 2.0, respectively), whereas the NS-LBP group showed similar pain intensities in all 3 postural situations (5.3, 4.0, and 4.9, respectively). Conclusion. This study revealed that LBP characteristics may provide important information for distinguishing ESS from other low back disorders. Because early diagnosis is essential for the treatment of ESS, MRI examination is recommended for patients showing severe pain in motion, but less pain when standing or sitting. Level of Evidence: 3

Wrist extension strength required for power grip: a study using a radial nerve block model

The aim of this study was to investigate the correlation of wrist extension strength (WES) and grip strength (GS) using a radial nerve block, and to determine the WES required to prevent the “wrist flexion phenomenon” (antagonistic WES) when making a fist. We tested 14 arms in seven healthy males. WES and GS were measured before blocking as standard WES and standard GS. All participants then had radial nerve blocks with mepivacaine hydrochloride. During the recovery process from radial nerve blockade, WES and GS were recorded every 5 minutes. There was a very strong correlation between WES and GS (p < 0.0001). The mean antagonistic WES was 51% of standard WES, and the mean GS, recorded at the same time, was 66% of standard GS.

Distribution of hip pain in patients with idiopathic osteonecrosis of the femoral head

Abstract Objective: To determine the distribution of referred hip pain in patients with idiopathic osteonecrosis of the femoral head (ION). Methods: We prospectively documented 119 hips in 90 patients with ION (mean age 51 years). Patients identified the location of pain originating in their hip on a drawing of the body. Osteoarthritis of the hip (OA) was used as a historical cohort. Results: Referral of pain originating from the hip in patients with ION was 93% (111 hips) to the groin, 68% (81 hips) to the knee, 36% (43 hips) to the anterior thigh, 34% (40 hips) to the buttock, 18% (22 hips) to the lower leg, 9% (11 hips) to the greater trochanter, and 8% (9 hips) to the low back. About 97% (115 hips) of pain was located in the hip region (groin, buttock, and greater trochanter) and 77% (92 hips) showed referred pain (anterior thigh, knee, lower leg, and low back). Pain from ION was significantly more frequent in the knee and lower leg, but significantly less frequent in the lower back than pain from OA. Conclusion: We should be aware of ION masquerading as pain in the knee or anterior thigh.