Quantitative Analysis of the Effect of Stereotactic Radiosurgery for Postoperative Residual Cervical Dumbbell Tumors: A Multicenter Retrospective Cohort Study

OBJECTIVE

Stereotactic radiosurgery (SRS) has been performed for spinal tumors. However, the quantitative effect of SRS on postoperative residual cervical dumbbell tumors remains unknown. This study aimed to quantitatively evaluate the efficacy of SRS for treating postoperative residual cervical dumbbell tumors.

METHODS

We retrospectively reviewed cases of postoperative residual cervical dumbbell tumors from 1995 to 2020 in 2 tertiary institutions. Residual tumors underwent SRS (SRS group) or were observed with clinical and magnetic resonance imaging (MRI) follow-up (observation group). Tumor regrowth rates were compared between the SRS and observation groups. Additionally, risk factors for tumor regrowth were analyzed.

RESULTS

A total of 28 cervical dumbbell tumors were incompletely resected. Eight patients were in the SRS group, and 20 in the observation group. The mean regrowth rate was not significantly lower (p = 0.784) in the SRS group (0.18 ± 0.29 mm/mo) than in the observation group (0.33 ± 0.40 mm/mo). In the multivariable Cox regression analysis, SRS was not a significant variable (hazard ratio [HR], 0.57; 95% confidence interval [CI], 0.18-1.79; p = 0.336).

CONCLUSION

SRS did not significantly decrease the tumor regrowth rate in our study. We believe that achieving maximal resection during the initial operation is more important than postoperative adjuvant SRS.

Unilateral Pediculectomy and Reduction with Short-Segment Pedicle Screw Fixation for Thoracolumbar Burst Fracture: A Case Series

BACKGROUND

This study aimed to evaluate the efficacy of unilateral pediculectomy and reduction with short-segment pedicle screw fixation for thoracolumbar burst fracture.

METHODS

We retrospectively reviewed patients who underwent a unilateral pediculectomy and reduction with short-segment fixation and interbody fusion for thoracolumbar burst fracture. The unilateral pediculectomy created sufficient space to approach the ventral side of the spinal cord for removing bone fragments and insertion of an interbody cage to correct kyphosis. Lumbar lordosis (LL), pelvic incidence (PI) minus LL, and segmental Cobb angle were measured at 3 time points: preoperatively, postoperatively, and final follow-up. Furthermore, sagittal vertical axis (SVA) was measured to assess global sagittal balance at the final follow-up.

RESULTS

A total of 10 patients, with a mean age of 39.8 ± 21.0, underwent the surgical procedure. All patients had a thoracolumbar injury classification and severity score > 5. The mean follow-up period was 15.8 ± 13.9 months. The mean postoperative LL (46.0 ± 5.8) was significantly higher (P = 0.008) than the preoperative measurement (32.8 ± 8.2). The mean postoperative PI minus LL (2.2 ± 8.4) was not significantly lower (P = 0.051) than preoperative measurement (15.4 ± 12.6). The mean postoperative segmental Cobb angle (11.4 ± 8.4) was significantly higher (P < 0.001) than the preoperative measurement (-11.6 ± 10.9). At the final follow-up, the mean sagittal vertical axiswas 10.0 ± 28.8 mm.

CONCLUSIONS

Unilateral pediculectomy and reduction with short-segment fixation and interbody fusion served as an efficient surgical method for thoracolumbar burst fracture.

Antinociceptive effects of nefopam activating descending serotonergic modulation via 5-HT2 receptors in the nucleus raphe magnus

BACKGROUND

Nefopam is a centrally acting antinociceptive drug; however, the underlying mechanisms are not fully understood. This study investigated the supraspinal mechanisms of nefopam.

METHODS

The effects of intraperitoneally administered nefopam were assessed in rats using the formalin test, and the mechanisms were investigated by intrathecal or intra-nucleus raphe magnus (NRM) pre-treatment with the serotonin (5-HT) receptor antagonist or 5-HT2 receptor antagonist. The change in extracellular 5-HT levels was measured by spinal cord microdialysis.

RESULTS

Intraperitoneally administered nefopam showed antinociceptive effects in the rat formalin test, which were reversed by intrathecal pre-treatment with 5-HT receptor antagonist dihydroergocristine. Microdialysis study revealed that systemic nefopam significantly increased 5-HT level in the spinal dorsal horn. Pretreatment of cinanserin, a 5-HT2 receptor antagonist, into the NRM blocked the antinociceptive effects of intraperitoneally delivered nefopam. Direct injection of nefopam into the NRM mimicked the effects of systemic nefopam, and this effect was reversed by intra-NRM cinanserin pre-treatment. The increase in spinal level of 5-HT by systemic nefopam was attenuated by intra-NRM cinanserin pre-treatment.

CONCLUSION

The antinociceptive effects of systemically administered nefopam are mediated by 5-HT2 receptors in the NRM, which recruit the descending serotonergic fibres to increase the release of 5-HT into the spinal dorsal horn.

SIGNIFICANCE

This study revealed supraspinal mechanisms of nefopam-produced analgesia mediated by 5-HT2 receptors in the NRM recruiting the descending serotonergic fibres to increase the release of 5-HT into the spinal dorsal horn. These observations support a potential role for nefopam in multimodal analgesia based on its distinct mechanisms of action that are not shared by the other analgesics.

Differential effects of two phosphodiesterase 4 inhibitors against lipopolysaccharide-induced neuroinflammation in mice

BACKGROUND

Several phosphodiesterase 4 (PDE4) inhibitors have emerged as potential therapeutics for central nervous system (CNS) diseases. This study investigated the pharmacological effects of two selective PDE4 inhibitors, roflumilast and zatolmilast, against lipopolysaccharide-induced neuroinflammation.

RESULTS

In BV-2 cells, the PDE4 inhibitor roflumilast reduced the production of nitric oxide and tumor necrosis factor-α (TNF-α) by inhibiting NF-κB phosphorylation. Moreover, mice administered roflumilast had significantly reduced TNF-α, interleukin-1β (IL-1β), and IL-6 levels in plasma and brain tissues. By contrast, zatolmilast, a PDE4D inhibitor, showed no anti-neuroinflammatory effects in vitro or in vivo. Next, in vitro and in vivo pharmacokinetic studies of these compounds in the brain were performed. The apparent permeability coefficients of 3 µM roflumilast and zatolmilast were high (> 23 × 10^-6 cm/s) and moderate (3.72-7.18 × 10^-6 cm/s), respectively, and increased in a concentration-dependent manner in the MDR1-MDCK monolayer. The efflux ratios were < 1.92, suggesting that these compounds are not P-glycoprotein substrates. Following oral administration, both roflumilast and zatolmilast were slowly absorbed and eliminated, with time-to-peak drug concentrations of 2-2.3 h and terminal half-lives of 7-20 h. Assessment of their brain dispositions revealed the unbound brain-to-plasma partition coefficients of roflumilast and zatolmilast to be 0.17 and 0.18, respectively.

CONCLUSIONS

These findings suggest that roflumilast, but not zatolmilast, has the potential for use as a therapeutic agent against neuroinflammatory diseases.

Imbalance in the spinal serotonergic pathway induces aggravation of mechanical allodynia and microglial activation in carrageenan inflammation

Background

This study investigated the effect of an excess and a deficit of spinal 5-hydroxytryptamine (5-HT) on the mechanical allodynia and neuroglia activation in a rodent pain model of carrageenan inflammation.

Methods

Male Sprague-Dawley rats were implanted with an intrathecal (i.t.) catheter to administer the drug. To induce an excess or deficit of 5-HT in the spinal cord, animals were given either three i.t. 5-HT injections at 24-hour intervals or a single i.t. injection of 5,7-dihydroxytryptamine (5,7-DHT) before carrageenan inflammation. Mechanical allodynia was measured using the von Frey test for 0-4 hours (early phase) and 24-28 hours (late phase) after carrageenan injection. The changes in the activation of microglia and astrocyte were examined using immunofluorescence of the dorsal horn of the lumbar spinal cord.

Results

Both an excess and a deficit of spinal 5-HT had no or a minimal effect on the intensity of mechanical allodynia during the early phase but prevented the attenuation of mechanical allodynia during the late phase, which was observed in animals not treated with i.t. 5-HT or 5,7-DHT. Animals with an excess or deficit of 5-HT showed stronger activation of microglia, but not astrocyte, during the early and late phases, than did normal animals.

Conclusions

Imbalance in the descending 5-HT pathway in the spinal cord could aggravate the mechanical allodynia and enhance the activation of microglia, suggesting that the spinal 5-HT pathway plays an essential role in maintaining the nociceptive processing in balance between facilitation and inhibition in inflammatory pain caused by carrageenan inflammation.

A Machine Learning-Based Prognostic Model for the Prediction of Early Death After Traumatic Brain Injury: Comparison with the Corticosteroid Randomization After Significant Head Injury (CRASH) Model

BACKGROUND

Machine learning (ML) has been used to predict the outcomes of traumatic brain injury. However, few studies have reported the use of ML models to predict early death. This study aimed to develop ML models for early death prediction and to compare performance with the corticosteroid randomization after significant head injury (CRASH) model.

METHODS

We retrospectively reviewed traumatic brain injury patients between February 2017 and August 2021. The patients were randomly assigned to a training set and a test set. Predictive variables included clinical findings, laboratory values, and computed tomography findings. The ML models (random forest, support vector machine [SVM], logistic regression) were developed with the training set. The CRASH model is a prognostic model that was developed based on 10,008 patients included in the CRASH trial. The ML and CRASH models were applied to the test set to evaluate the performance.

RESULTS

A total of 423 patients were included; 317 and 106 patients were randomly assigned to the training and test sets, respectively. The area under the curve was highest in the SVM (0.952, 95% confidence interval = 0.906-0.990) and lowest in the CRASH model (0.942, 95% confidence interval = 0.886-0.999). There were no significant differences between the area under the curves of the ML and CRASH models (P = 0.899 for random forest vs. the CRASH model, P = 0.760 for SVM vs. the CRASH model, P = 0.806 for logistic regression vs. the CRASH model).

CONCLUSIONS

The ML models may have comparable performances compared to the CRASH model despite being developed with a smaller sample size.

Venous outflow-targeted coil embolization of direct carotid-cavernous fistulas

BACKGROUND

Coil embolization is the mainstay treatment for carotid-cavernous fistulas (CCFs). However, few studies have reported entire occlusion of engorged veins to interrupt venous outflow. We report our experience with venous outflow-targeted coil embolization of direct CCFs.

METHODS

We retrospectively reviewed all the patients diagnosed with direct CCFs treated with venous outflow-targeted coil embolization between November 2013 and February 2020. Venous outflow-targeted coil embolization of the CCFs was performed as follows. First, transarterial stent-assisted coil embolization of CCFs was performed. If the venous outflow to the engorged veins persisted after transarterial stent-assisted coil embolization, entire occlusion of the engorged veins and additional coil packing within the cavernous sinus were performed to interrupt the venous outflow.

RESULTS

Ten patients had undergone venous outflow-targeted coil embolization, 6 women (60%) and 4 men (40%). Transfemoral cerebral angiography showed high-flow, direct CCFs in all the patients. Venous outflow occurred through the superior ophthalmic vein (SOV) in all the patients and was completely interrupted by the entire occlusion of the engorged veins with fibered coils. Three patients (30%) had undergone additional treatment in a supplementary manner because of recurrent symptoms (chemosis in 1 patient, faint tinnitus in 2 patients) in the early postprocedural period (1 to 4 weeks). All the symptoms were resolved on follow-up. No additional recurrence was found during follow-up (1-75 months). No peri-procedural complications were encountered.

CONCLUSIONS

Venous outflow-targeted coil embolization of CCFs would be a safe and effective treatment method.

Anastomosis and Endovascular Treatment of Iatrogenic Vertebral Artery Injury

Iatrogenic vertebral artery injury (VAI) that occurs during cervical spine surgery can cause life-threatening complications, such as arteriovenous fistulas, catastrophic bleeding, neurological impairment, cerebral ischemia, and death. We report a case of dominant VAI during surgery and the treatment of a 60-year-old man diagnosed with a C1-2-3 metastatic spine tumor from urothelial carcinoma. Active bleeding occurred during tumor resection using pituitary forceps, immediately followed by gauze packing and manual compression. Post further resection, we found that the vertebral artery (VA) was completely severed. After temporary clamping on both sides of the damaged VA, an artificial graft anastomosis was performed. After verifying that the flow was intact using Doppler Sonography, Occiput-C1-4-5-6 posterolateral fusion was performed. Angiography was performed immediately after surgery. We found a thrombus occluding the left VA, and performed mechanical thrombectomy and stent insertion. The final angiography showed good VA flow with no emboli. In this case, VA anastomosis and endovascular treatment were performed within a relatively short period of time post VAI, and the patient was able to recover without any neurological deficits.

Comparisons of surgical conditions of deep and moderate neuromuscular blockade through multiple assessments and the quality of postoperative recovery in upper abdominal laparoscopic surgery

STUDY OBJECTIVE

To determine the effect of deep neuromuscular blockade (NMB) on surgical field conditions through multiple assessments during pneumoperitoneum and evaluate the effect of the depth of intraoperative NMB on the quality of postoperative recovery over multiple time periods.

DESIGN

Prospective randomized study.

SETTING

Operating room of a university hospital.

PATIENTS

Eighty non-morbidly obese patients (ASA physical status 1-2) who were scheduled to undergo laparoscopic gastrectomy in the reverse Trendelenburg position.

INTERVENTIONS

Patients were allocated to either the deep or moderate NMB group. The depth of NMB was maintained at a post-tetanic count of 1 for deep NMB with a continuous infusion of rocuronium and at a train-of-four count of 1 for moderate NMB with a small intermittent bolus of cisatracurium.

MEASUREMENTS

Single-blinded scoring of the quality of the surgical field condition was performed by a surgeon using a five-point scale in a 15-min interval during pneumoperitoneum. The quality of postoperative recovery was assessed using the Postoperative Quality of Recovery Scale (PostopQRS) on the day before surgery (baseline) and 1 h, 1 day, and 6 days after surgery.

MAIN RESULTS

Optimal surgical field condition was rated in 87.0% (449/516) and 72.3% (370/512) of all measurements during deep and moderate NMB, respectively (P < 0.001). The percentage of patients maintaining a good-to-optimal condition throughout pneumoperitoneum was higher in the deep NMB group than in the moderate NMB group. There were no significant differences in the percentage of recovered patients between the two groups for all domains and all timepoints.

CONCLUSIONS

Multiple assessments of the surgical field condition demonstrated that deep NMB provided a more satisfactory surgical field condition than moderate NMB during laparoscopic gastrectomy. However, the quality of postoperative recovery, assessed using the PostopQRS, was not different between the two groups according to the depth of NMB.

Process of Obtaining Social Consensus and 3-Year Functional Outcomes of the First Hand Allotransplantation in Korea

BACKGROUND

On February 2, 2017, the surgical team of ten board-certified hand specialists of W Hospital in Korea successfully performed the nation's first hand transplantation at Yeungnam University Medical Center (YUMC). This paper reports on the legal, financial, and cultural hurdles that were overcome to open the way for hand transplantation and its functional outcomes at 36 months after the operation.

METHODS

W Hospital formed a memorandum of understanding with Daegu city and YUMC to comply with government regulations regarding hand transplantation. Campaigns were initiated in the media to increase public awareness and understanding. With the city's financial and legal support and the university's medical cooperation, a surgical team performed a left distal forearm hand transplantation from a brain-dead 48-year-old man to a 35-year-old left-handed man.

RESULTS

With this successful allotransplantation, the Korean Act on Organ Transplantation has now been amended to include hand transplantation. Korean national health insurance has also begun covering hand transplantation. Functional outcome at 36 months after the operation showed satisfactory progress in both motor and sensory functions. The disabilities of the arm, shoulder, and hand score were 23. The final Hand Transplantation Score was 90 points. Functional brain magnetic resonance imaging shows significant cortical reorganization of the corticospinal tract, and reinnervation of intrinsic muscle is observed.

CONCLUSIONS

Hand transplantation at the distal forearm shows very satisfactory outcomes in functional, aesthetical, and psychological aspects. Legal and financial barriers against hand transplantation have long been the most burdensome issues. Despite this momentous success, there have been no other clinical applications of vascularized composite allotransplantation due to the limited acceptance by Korean doctors and people. Further public education campaigns for vascularized composite allotransplantation are needed to increase awareness and acceptance.

Prostaglandin D2 contributes to cisplatin-induced neuropathic pain in rats via DP2 receptor in the spinal cord

Background

Chemotherapy-induced peripheral neuropathy (CIPN) is a major reason for stopping or changing anticancer therapy. Among the proposed pathomechanisms underlying CIPN, proinflammatory processes have attracted increasing attention. Here we assessed the role of prostaglandin D² (PGD²) signaling in cisplatin-induced neuropathic pain.

Methods

CIPN was induced by intraperitoneal administration of cisplatin 2 mg/kg for 4 consecutive days using adult male Sprague-Dawley rats. PGD² receptor DP1 and/or DP2 antagonists were administered intrathecally and the paw withdrawal thresholds were measured using von Frey filaments. Spinal expression of DP1, DP2, hematopoietic PGD synthase (H-PGDS), and lipocalin PGD synthase (L-PGDS) proteins were analyzed by western blotting.

Results

The DP1 and DP2 antagonist AMG 853 and the selective DP2 antagonist CAY10471, but not the DP1 antagonist MK0524, significantly increased the paw withdrawal threshold compared to vehicle controls (P = 0.004 and P < 0.001, respectively). Western blotting analyses revealed comparable protein expression levels in DP1 and DP2 in the spinal cord. In the CIPN group the protein expression level of L-PGDS, but not of H-PGDS, was significantly increased compared to the control group (P < 0.001).

Conclusions

The findings presented here indicate that enhanced PGD² signaling, via upregulation of L-PGDS in the spinal cord, contributes to mechanical allodynia via DP2 receptors in a cisplatin-induced neuropathic pain model in rats, and that a blockade of DP2 receptor activation may present a novel therapeutic target for managing CIPN.

Systemically administered neurotensin receptor agonist produces antinociception through activation of spinally projecting serotonergic neurons in the rostral ventromedial medulla

Background

Supraspinal delivery of neurotensin (NTS), which may contribute to the effect of a systemically administered agonist, has been reported to be either pronociceptive or antinociceptive. Here, we evaluated the effects of systemically administered NTSR1 agonist in a rat model of neuropathic pain and elucidated the underlying supraspinal mechanism.

Methods

Neuropathic pain was induced by L5 and L6 spinal nerve ligation in male Sprague-Dawley rats. The effects of intraperitoneally administered NTSR1 agonist PD 149163 was assessed using von Frey filaments. To examine the role of 5-HT neurotransmission, a serotonin (5-HT) receptor antagonist dihydroergocristine was pretreated intrathecally, and spinal microdialysis studies were performed to measure the change in extracellular level of 5-HT in response to PD 149163 administration. To investigate the supraspinal mechanism, NTSR1 antagonist 48692 was microinjected into the rostral ventromedial medulla (RVM) prior to systemic PD 149163. Additionally, the effect of intrathecal DHE on intra-RVM PD 149163 was assessed.

Results

Intraperitoneally administered PD 149163 exhibited a dose-dependent attenuation of mechanical allodynia. This effect was partially reversed by intrathecal pretreatment with dihydroergocristine and was accompanied by an increased extracellular level of 5-HT in the spinal cord. The PD 149163-produced antinociception was also blocked by intra-RVM SB 48692. Direct injection of PD 149163 into the RVM mimicked the maximum effect of the same drug delivered intraperitoneally, which was reversed by intrathecal dihydroergocristine.

Conclusions

These observations indicate that systemically administered NTSR1 agonist produces antinociception through the NTSR1 in the RVM, activating descending serotonergic projection to release 5-HT into the spinal dorsal horn.

Progressive Cervical Spondylotic Myelopathy Caused by Tic Disorders in a Young Adult with Tourette Syndrome

Involuntary movement of the cervical spine can cause damage to the cervical spinal cord. Cervical myelopathy may occur at an early age in involuntary movement disorders, such as tics. We report the case of a 21-year-old man with Tourette syndrome, who developed progressive quadriparesis, which was more severe in the upper extremities. The patient had abnormal motor tics with hyperflexion and hyperextension of the cervical spine for more than 10 years. High-signal intensity intramedullary lesions were observed at C3-4-5-6 level on T2 weighted magnetic resonance imaging. Examinations were performed for high-signal intensity intramedullary lesions that may occur at a young age, but no other diseases were detected. Botulinum toxin injection to the neck musculature and medication for tic disorders were administered. However, the myelopathy was further aggravated, as the involuntary cervical movement still remained. Therefore, laminoplasty was performed at C3-4-5-6, with posterior fixation at C2-3-4-5-6-7 to alleviate the symptoms. The neurological signs and symptoms improved dramatically. The management of tic disorders should be the first priority during treatment. However, surgical treatment may be necessary, if symptoms worsen after appropriate treatment.

P5989Effect of neprilysin inhibitor for ischemic mitral regurgitation after myocardial injury

Background

After myocardial infarction (MI), mitral valve (MV) tethering and fibrosis stimulate functional mitral regurgitation (MR), resulting in high morbidity of heart failure and cardiac mortality. However, pharmacological treatment has not been proven effective in reducing ischemic MR. MV change post-MI is associated with an excessive endothelial-to-mesenchymal transition (EMT) by transforming growth factor (TGF)-β overexpression and also with left ventricular (LV) remodeling. In a recent clinical study using echocardiography, angiotensin receptor neprilysin inhibitor (ARNI) reduced functional MR to a greater extent than did valsartan, but the mechanism was not revealed.

Purpose

This study tested the hypothesis that treatment of neprilysin inhibitor attenuates functional MR after MI by facilitating LV reverse remodeling and suppressing EMT which mitigates inadequate leaflet adaptation.

Methods

In male Sprague-Dawley rats (n=31), functional MR was induced by occluding the left circumflex coronary artery. Two weeks after MI, MR and LV dilatation were confirmed by echocardiography and magnetic resonance imaging (MRI). Rats were randomly assigned to LCZ696 treatment (ARNI, 60 mg/kg/d, n=10), valsartan treatment (30mg/kg/d, n=10), or corn oil only (MR control group; n=11). After 6 weeks, LV volumes, functions and MR extent were quantified by using echocardiography, cardiac MRI and pressure-volume loop analysis. Also, excised mitral leaflets and LV were analyzed by histopathology and primary cultured valvular endothelial cells (VECs) were evaluated focusing on molecular changes.

Results

LCZ696 significantly attenuated post-MI LV dilatation after 6 weeks when compared with the control group (LV end-diastolic volume (EDV), 461.3±41.3 uL versus 525.1±78.2 uL; p<0.05), while valsartan did not (LV EDV, 471.2±26.8 uL; p>0.05 to control). There were no significant differences in the change of arterial pressure and ejection fraction between the treatment groups, however, dP/dt was greater in the LCZ696 group than in the MR control group (8203±286 mmHg/s for LCZ696 versus 6936±555 mmHg/s for MR control; p=0.01). MR extent and LA volume were significantly decreased in the LCZ696 group compared with the valsartan group. Pathological analysis showed that fibrosis was more prominent in the MR control than in the LCZ696 group. LCZ696 strongly reduced leaflet thickness, TGF-β, and downstream phosphorylated extracellular-signal-regulated kinase and EMT (25.4±11.8% vs. 53.4±12.6% α-smooth muscle actin-positive VECs; p<0.05). Leaflet area increased comparably (5%) in the LCZ696 group compared with the valsartan group.

Conclusions

Neprilysin inhibitor has positive effects on LV reverse remodeling and also directly modulates profibrotic changes of MV leaflets post-MI without eliminating adaptive growth. Understanding the mechanisms could provide new opportunities to ARNI reducing ischemic MR.

Acknowledgement/Funding

This work was supported by the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2014R1A6A3A04056205). It was also

Epidemiology of C5 Palsy after Cervical Spine Surgery: A 21-Center Study

Objective

C5 palsy is a severe complication after cervical spine surgery, the pathophysiology of which remains unclear. This multicenter study investigated the incidence of C5 palsy following cervical spine surgery in Korea.

Methods

We conducted a retrospective multicenter study involving 21 centers from the Korean Cervical Spine Study Group. The inclusion criteria were cervical spine surgery patients between 2012 and 2016, excluding cases of neck surgery. In patients with C5 palsy, the operative methods, disease category, onset time of C5 palsy, recovery time, C5 manual muscle testing (MMT) grade, and post-C5 palsy management were analyzed.

Results

We collected 15,097 cervical spine surgery cases from 21 centers. C5 palsy occurred in 88 cases (0.58%). C5 palsy was more common in male patients (p=0.019) and after posterior approach procedures (p<0.001). C5 palsy usually occurred within 3 days after surgery (77 of 88, 87.5%) and most C5 palsy patients recovered within 6 months (51 of 88, 57.95%). Thirty C5 palsy patients (34.09%) had motor weakness, with an MMT grade≤2. Only four C5 palsy patients (4.5%) did not recover during follow-up. Posterior cervical foraminotomy was performed in 7 cases (7.95%), and steroids were used in 56 cases (63.63%). Twenty-six cases (29.55%) underwent close observation only.

Conclusion

The overall incidence of C5 palsy was relatively low (0.58%). C5 palsy was more common after posterior cervical surgery and in male patients. C5 palsy usually developed within 3 days after surgery, and more than half of patients with C5 palsy recovered within 6 months.

Quaternized Polysulfone Cross-Linked N,N-Dimethyl Chitosan-Based Anion-Conducting Membranes

Anion-conducting membranes were obtained following the cross-linking of 1,4-diazoniabicycle[2.2.2]octane functionalized-polysulfone with N,N-dimethyl chitosan (DMC). The ionic conductivity of the composite membranes was controlled by the amount of DMC. The influence of the amount of DMC on water uptake, swelling ratio, and ionic conductivity of the obtained membrane was studied. The membrane with 2 wt% DMC exhibited an ionic conductivity of 54 mS/cm and 94 mS/cm at 25 °C and 70 °C, respectively. The membrane showed good dimensional stability under hydrated conditions. A urea/O₂ fuel cell, built using the composite membrane, exhibited a peak power density of 4.4 mW/cm² with a current density of 16.22 mA/cm² at 70 °C.

Effect of relative humidity on inactivation of foodborne pathogens using chlorine dioxide gas and its residues on tomatoes

The effect of relative humidity (RH) on the antimicrobial efficacy of chlorine dioxide (ClO₂ ) gas against foodborne pathogens on tomatoes was evaluated. Also, levels of ClO₂ residues on tomatoes after exposure to ClO₂ gas under different RH conditions were measured to determine the quantity of solubilized ClO₂ gas on tomato surfaces. Escherichia coli O157:H7, Salmonella Typhimurium and Listeria monocytogenes were inoculated on tomatoes and exposed to ClO₂ gas (5, 10, 20 and 30 ppmv) under different RH conditions (50, 70 and 90%). As ClO₂ gas concentration and treatment time increased, significant differences (P < 0·05) were observed between inactivation levels under different RH conditions. Exposure to 30 ppmv of ClO₂ gas (50% RH) for 20 min resulted in 1·22-1·52 log reductions of the three foodborne pathogens. Levels of the three foodborne pathogens were reduced to below the detection limit (0·48 log CFU per cm² ) within 15 min when exposed to 30 ppmv of ClO₂ gas at 70% RH and within 10 min at 90% RH. At a given ClO₂ gas concentration, ClO₂ residues on tomatoes significantly (P < 0·05) increased with increasing RH, and there were close correlations between log reductions of pathogens and ClO₂ residues on tomatoes.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study reported on the correlation between the amount of ClO₂ residues on produce surfaces and the level of inactivation of pathogens after ClO₂ gas treatment. Variations in RH have great effect on the solubilization of ClO₂ gas on tomato surfaces considering that ClO₂ residues on tomatoes increased with increasing RH. Also, the amount of ClO₂ residues on tomatoes is positively correlated with the level of inactivation of pathogens. The results of this study provide insights for predicting inactivation patterns of foodborne pathogens by ClO₂ gas for practical application by the fresh produce industry.

Influence of Food with High Moisture Content on Oxygen Barrier Property of Polyvinyl Alcohol (PVA)/Vermiculite Nanocomposite Coated Multilayer Packaging Film

This study investigates the potential complications in applying nanoclay-based waterborne coating to packaging films for food with high moisture content. Multilayer packaging films were prepared by dry laminating commercially available polyvinyl alcohol (PVA)/vermiculite nanocomposite coating films and linear low-density polyethylene film, and the changes in oxygen barrier properties were investigated according to different relative humidity using 3 types of food simulants. When the relative humidity was above 60%, the oxygen permeability increased sharply, but this was reversible. Deionized water and 3% acetic acid did not cause any large structural change in the PVA/vermiculite nanocomposite but caused a reversible deterioration of the oxygen barrier properties. In contrast, 50% ethanol, a simulant for the semifatty food, induced irreversible structural changes with deterioration of the oxygen barrier property. These changes are due to the characteristics of PVA rather than vermiculite.

PRACTICAL APPLICATION

We believe this manuscript would be of interest to the wide group of researchers, organizations, and companies in the field of developing nanoclay-based gas barrier packaging for foods with high moisture content. Hence, we wish to diffuse our knowledge to the scientific community.

Epidural Metastasis in Malignant Thymoma Mimicking Epidural Abscess: Case Report and Literature Review

Thymoma and thymic carcinoma are rare epithelial tumors that originate from the thymus gland. Extrathoracic metastases occur in the liver, kidney, and bone in 1% to 15% of patients. Although thymoma and thymic carcinoma exhibit highly aggressive biological behavior, spinal metastasis is rare. We describe a 78-year-old man with left wrist and grasp weakness that occurred 7 days before admission. The patient underwent thymoma surgery 7 years ago and was cured. Magnetic resonance images showed a rim-enhanced mass in the C6-7-T1 epidural space. C6-7-T1 laminectomy was performed and the mass was removed. Histological examination was performed and patient was diagnosed with metastatic thymoma. The previous reported case occurred with involvement of the vertebral body or posterior element, but our case was mostly rim-enhanced and appeared as an abscess and intradural extramedullary tumor.

A Case of Cardiac Arrest due to Multivessel, Diffuse Coronary Spasm in Moyamoya Disease

Moyamoya disease is characterized by progressive stenosis of the distal portion of the internal carotid arteries and fragile collateral vessels in the brain. The precise pathogenesis is still not known. Although extracranial vessel involvement is very rare, coronary arterial involvement has recently been reported. Here, we report a case of diffuse, multivessel coronary spasm leading to cardiac arrest and myocardial infarction in a 47-year-old man with moyamoya disease with no underlying emotional or physical stress.

What Effects Does Necrotic Area of Contrast-Enhanced MRI in Osteoporotic Vertebral Fracture Have on Further Compression and Clinical Outcome?

Objective

The objective of this study was to analyze the correlation between further compression and necrotic area in osteoporotic vertebral fracture (OVF) patients with contrast-enhanced magnetic resonance imaging (CEMRI). In addition, we investigated the radiological and clinical outcome according to the range of the necrotic area.

Methods

Between 2012 and 2014, the study subjects were 82 OVF patients who did not undergo vertebroplasty or surgical treatment. The fracture areas examined on CEMRI at admission were defined as edematous if enhancement was seen and as necrotic if no enhancement was seen. The correlation between further compression and the necrotic and edematous areas of CEMRI, age, and bone mineral density was examined. Also, necrotic areas were classified into those with less than 25% (non-necrosis group) and those with more than 25% (necrosis group) according to the percentages of the entire vertebral body. For both groups, further compression and the changes in wedge and kyphotic angles were examined at admission and at 1 week, 3 months, and 6 months after admission, while the clinical outcomes were compared using the visual analog scale (VAS) and Eastern Cooperative Oncology Group (ECOG) performance status grade.

Results

Further compression was 14.78±11.11% at 1 month and 21.75±14.43% at 6 months. There was a very strong correlation between the necrotic lesion of CEMRI and further compression (r=0.690, p<0.001). The compression of the necrosis group was 33.52±12.96%, which was higher than that of the non-necrosis group, 14.96±10.34% (p<0.005). Also, there was a statistically significantly higher number of intervertebral cleft development and surgical treatments being performed in the necrosis group than in the non-necrosis group (p<0.005). Moreover, there was a statistical difference in the decrease in the height of the vertebral body, and an increase was observed in the kyphotic change of wedge angle progression. There was also a difference in the VAS and ECOG performance scales.

Conclusion

The necrotic area of CEMRI in OVF had a strong correlation with further compression over time. In addition, with increasing necrosis, intervertebral clefts occurred more frequently, which induced kyphotic changes and resulted in poor clinical outcomes. Therefore, identifying necrotic areas by performing CEMRI on OVF patients would be helpful in determining their prognosis and treatment course.

A Viewpoint on Treatment of Traumatic Bilateral Basal Ganglia Hemorrhage in a Child: Case Report

Traumatic basal ganglia hemorrhage (TBGH) is a rare presentation of head injuries. Bilateral lesions are extremely rare. The pathophysiologic mechanism of bilateral TBGH seems to be the same as diffuse axonal injury. However, limited information about childhood bilateral TBGH is available in the literature. We report the case of a child with bilateral TBGH treated with stereotactic aspiration of hemorrhage and periodic urokinase irrigation.

Clinical Experiences of Uncommon Motor Neuron Disease: Hirayama Disease

Hirayama disease, juvenile muscular atrophy of the distal upper limb, is a rare disease predominantly affecting the anterior horn cells of the cervical spinal cord in young men. This cervical myelopathy is associated with neck flexion. It should be suspected in young male patients with a chronic history of weakness and atrophy involving the upper extremities followed by clinical stability in few years. Herein, we report 2 cases of Hirayama disease on emphasis of diagnostic approach and describe the pathognomonic findings at flexion magnetic resonance imaging.

The Safety and Decision Making of Instrumented Surgery in Infectious Spondylitis

OBJECTIVE

Infectious spondylitis is mostly managed by appropriate antibiotic treatment options, and some patients may require surgical interventions. However, surgical interventions that use spinal instrumentation to correct the mechanical instability may be associated with the risk of an increase in the recurrence rate. In this study, we investigated whether spinal instrumentation effects on recurrence of infectious spondylitis.

METHODS

The study was conducted as a retrospective study by dividing the subjects into the noninstrumentation surgery and instrumentation surgery groups among a total of 95 patients who had received surgical interventions in infectious spondylitis from 2009 to 2014. The study investigated patient variables such as underlying illness, presumed source of infection, clinical data, laboratory and radiological data, and ultimate outcome, and compared them between the 2 groups.

RESULTS

In the 95 patients, instrumentation was not used in 21 patients but it was used in 74 patients. When the disease involved ≥3 vertebral bodies, lumbosacral level and epidural part, noninstrumentation surgery was mainly conducted, but when the disease involved the thoracic level and psoas muscle part, instrumentation surgery was mainly conducted. However, there were no differences between the 2 groups in terms of the recurrence rate and the incidence of primary failure.

CONCLUSION

The use of instrumentation in treating infectious spondylitis was determined by the level of involvement and part of the infection, but the use of instrumentation did not cause any increases in the recurrence rate and the incidence of primary failure.

High-fat diet-induced obesity exacerbates kainic acid-induced hippocampal cell death

BACKGROUND

Obesity has deleterious effects on the brain, and metabolic dysfunction may exacerbate the outcomes of seizures and brain injuries. However, it is unclear whether obesity affects excitotoxicity-induced neuronal cell death. The purpose of this study was to investigate the effects of a high-fat diet (HFD) on neuroinflammation and oxidative stress in the hippocampus of kainic acid (KA)-treated mice.

RESULTS

Mice were fed with a HFD or normal diet for 8 weeks and then received a systemic injection of KA. HFD-fed mice showed hypercholesterolemia, insulin resistance, and hepatic steatosis. HFD-fed mice showed greater susceptibility to KA-induced seizures, an increased number of terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-positive cells, neuroinflammation, and oxidative stress. Furthermore, we found that KA treatment increased HFD-induced calpain1, nuclear factor E2-related factor 2, and heme oxygenase-1 expression in the hippocampus.

CONCLUSIONS

These findings imply that complex mechanisms affected by obesity-induced systemic inflammation, neuroinflammation, ER stress, calcium overload, and oxidative stress may contribute to neuronal death after brain injury.

Infectious Spondylitis with Bacteremia Caused by Roseomonas mucosa in an Immunocompetent Patient

Roseomonas are a gram-negative bacteria species that have been isolated from environmental sources. Human Roseomonas infections typically occur in immunocompromised patients, most commonly as catheter-related bloodstream infections. However, Roseomonas infections are rarely reported in immunocompetent hosts. We report what we believe to be the first case in Korea of infectious spondylitis with bacteremia due to Roseomonas mucosa in an immunocompetent patient who had undergone vertebroplasty for compression fractures of his thoracic and lumbar spine.

Association of body composition with bone mineral density in northern Chinese men by different criteria for obesity

With impressive economic development, obesity has emerged as a critical public health issue in China. Recently it was reported that obesity has taken an adverse effect on osteoporosis. Because there is different body mass index (BMI) for obesity globally, studies based on BMI levels on association of obesity with osteoporosis were quite few. Therefore, we discussed the relationship of body composition with skeletal BMD according to WHO BMI and BMI on Working Group on Obesity in China (WGOC).

METHODS

A total of 502 adult men aged 20-89 were enrolled as healthy subjects for osteoporosis study at Qianfoshan Hospital, Shandong University between September 2008 and August 2010. According to WHO BMI, all subjects were divided into three groups: normal weight (18.5 ≤ BMI < 25 kg/m(2), n = 202), overweight (25 ≤ BMI < 30 kg/m(2), n = 242), and obesity (BMI ≥ 30 kg/m(2), n = 58). According to WGOC BMI, normal weight (18.5 ≤ BMI < 24 kg/m(2), n = 137), overweight (24 ≤ BMI < 28 kg/m(2), n = 225), and obesity (BMI ≥ 28 kg/m(2), n = 140). Total body and regional BMD, lean mass (LM), lean body mass index (LBMI), fat mass (FM), percent body fat (%BF) and fat mass index (FMI) were measured by dual-energy X-ray absorptiometry. Age-partial Pearson correlation analyses between body composition-related parameters and BMD. Multiple regression analyses were performed to explore the associations of BMD with LM, LBMI, FM, %BF and FMI.

RESULTS

Fat mass (FM), %BF, FMI, LM and LBMI were positively correlated with BMD at almost sites (P < 0.001) in all subjects. However, the relationship was not different among groups. LM, LBMI, FM and FMI were positively correlated with BMD (P < 0.01) in normal weight. LM and LBMI appeared significantly positive with BMD in overweight and obesity according to WHO and WGOC criteria. %BF and FMI were negative significance with BMD at total body and some regional BMD according to WHO criteria in overweight (P < 0.05). In two obese groups, %BF appeared negatively significant with BMD (P < 0.05) according to WGOC criteria, and %BF and FMI appeared negatively significant with BMD (P < 0.05) according to WHO criteria. In regression of independent variables as FM and LM, LM showed statistically positively significant relations with BMD at almost sites (P < 0.05) in all groups. FM appeared positively significant with BMD in normal groups and overweight group according to WGOC criteria. In regression of independent variables as %BF and FMI, %BF and FMI appeared statistically negatively significant relations with BMD in overweight and obesity, but %BF and FMI were inconsistent in same site.

CONCLUSIONS

Lean mass (LM) and LBMI could help to determinant of BMD, and %BF and FMI were adverse to BMD in overweight and obesity. Comparing with two criteria, we found the differences in fat-related parameters and BMD according to WHO criteria were more obvious than that according to WGOC criteria. We also found that %BF and FMI were useful to research the relationship between osteoporosis and obesity at the same time.

Investigation of thermal and electrical stabilities of a GdBCO coil using grease as an insulation material for practical superconducting applications

This paper presents the effects of thermal grease on the electrical and thermal characteristics of GdBCO pancake coils, observed through charge-discharge, sudden discharge, over-current, and thermal quench testing. In charge-discharge and sudden discharge tests, a coil using thermal grease as an insulation material demonstrated faster charging/discharging rates compared to a coil without turn-to-turn insulation. In the case of over-current tests, the coil using thermal grease exhibited the highest electrical stability. Furthermore, thermal quench testing showed the coil employing thermal grease to possess superior thermal characteristics, with rapid cooling and low temperature rise. Overall, the use of thermal grease as an insulation material may be a potential solution to the problems observed with the existing insulation materials, possessing fast charging/discharging rates with superior thermal and electrical stabilities.

Anesthetic requirements and stress hormone responses in chronic spinal cord-injured patients undergoing surgery below the level of injury: nitrous oxide vs remifentanil

BACKGROUND

Nitrous oxide (N2O) and remifentanil both have anesthetic-reducing and antinociceptive effects. We aimed to determine the anesthetic requirements and stress hormone responses in spinal cord-injured (SCI) patients undergoing surgery under sevoflurane anesthesia with or without pharmacodynamically equivalent doses of N2O or remifentanil.

METHODS

Forty-five chronic, complete SCI patients undergoing surgery below the level of injury were randomly allocated to receive sevoflurane alone (control, n = 15), or in combination with 67% N2O (n = 15) or target-controlled infusion of 1.37 ng/ml remifentanil (n = 15). Sevoflurane concentrations were titrated to maintain a Bispectral Index (BIS) value between 40 and 50. Measurements included end-tidal sevoflurane concentrations, mean arterial blood pressure (MAP), heart rate (HR), and plasma catecholamine and cortisol concentrations.

RESULTS

During surgery, MAP, HR, and BIS did not differ among the groups. Sevoflurane concentrations were lower in the N2O group (0.94 ± 0.30%) and the remifentanil group (1.06 ± 0.29%) than in the control group (1.55 ± 0.34%) (P < 0.001, both). Plasma concentrations of norepinephrine remained unchanged compared to baseline values in each group, with no significant differences among groups throughout the study. Cortisol levels decreased during surgery as compared to baseline values, and returned to levels higher than baseline at 1 h after surgery (P < 0.05) without inter-group differences.

CONCLUSIONS

Remifentanil (1.37 ng/ml) and N2O (67%) reduced the sevoflurane requirements similarly by 31-39%, with no significant differences in hemodynamic and neuroendocrine responses. Either remifentanil or N2O can be used as an anesthetic adjuvant during sevoflurane anesthesia in SCI patients undergoing surgery below the level of injury.

Evaluation of patient outcome after discontinuation of alfuzosin treatment for benign prostatic hyperplasia: a multicentre, prospective study

AIMS

The aim of this study was to assess patient outcome after discontinuation of alfuzosin treatment in patients with benign prostatic hyperplasia (BPH).

METHODS

This study included 200 BPH patients. Alpha-blockers were discontinued after 12 weeks of treatment when the International Prostatic Symptom Score (IPSS) was reduced to < 8 points, peak urine flow rate (Q(max)) was increased to ≥ 15 ml/s, the postvoiding residual (PVR) urine volume was ≤ 100 ml and the patient agreed to discontinue treatment. Urinary symptoms of the patients were assessed at 4, 8, 12 and 24 weeks after discontinuation of medication, and surveys were performed asking whether patients wanted to restart administration of medication.

RESULTS

Of 200 enrolled patients, 142 (71.00%) received 12 weeks of treatment with 10 mg of alfuzosin. The medication was discontinued in 58 of 142 patients (40.85%) because urinary symptoms had improved. Among these patients, follow-up observations were performed for 49 patients up to 24 weeks after treatment discontinued. Of these 49 patients, 28 (57.14%) showed correct urination without a need to restart treatment up to 24 weeks after the medication was discontinued. The discontinuation group demonstrated improved voiding symptoms, including Q(max) and PVR, relative to the re-administration group at baseline. Furthermore, the discontinuation group showed a smaller prostate volume than the re-administration group (p = 0.045).

CONCLUSION

When patients with BPH displayed symptomatic improvement upon treatment with alpha-blockers, the improvements were maintained in a select subpopulation of patients without the need to re-administer the alpha-blockers.

The analysis of patterns and risk factors of newly developed vertebral compression fractures after percutaneous vertebroplasty

OBJECTIVE

The purpose of this study was to investigate the patterns and the risk factors of newly developed vertebral compression fractures (VCFs) after percutaneous vertebroplasty (PVP).

METHODS

We performed a retrospective review of the 244 patients treated with PVP from September 2006 to February 2011. Among these patients, we selected 49 patients with newly developed VCFs following PVP as the new VCFs group, and the remaining 195 patients as the no VCFs group. The new VCFs group was further divided into 2 groups : an adjacent fractures group and a nonadjacent fractures group. The following data were collected from the groups : age, gender, body weight/height, body mass index (BMI), bone mineral density (BMD) score of the spine and femur, level of initial fracture, restoration rate of anterior/middle vertebral height, and intradiscal cement leakage, volume of polymethylmethacrylate (PMMA).

RESULTS

Age, gender, mean body height/weight, mean BMI and volume of PMMA of each of the group are not statistically significantly associated with fractures. In comparison between the new VCFs group and the no VCFs group, lower BMD, intradiscal cement leakage and anterior vertebral height restoration were the significant predictive factors of the fracture. In addition, new VCFs occurrence at the adjacent spines was statistically significant, when the initial fracture levels were confined to the thoracolumbar junction, among the subgroups of new VCFs.

CONCLUSION

Lower spinal BMD, the greater anterior vertebral height restoration rate and intradiscal cement leakage were confirmed as risk factors for newly formed VCFs after PVP.

Reverse latissimus dorsi muscle flap for an extensive soft tissue defect accompanied by infectious spondylitis

Spinal infection is an inflammatory process around the vertebral body, and it can extend to the epidural space, posterior elements and paravertebral soft tissues. Infectious spondylitis is a rare infectious disorder, which is often associated with significant neurologic deficits and mortality. When an extensive soft tissue defect is accompanied by infectious spondylitis, effective infection control and proper coverage of soft tissue are directly connected to successful outcomes. However, it is not simple to choose the appropriate treatment methods for infectious spondylitis accompanied by a soft tissue defect. Herein, we report a case of severe infectious spondylitis that was accompanied by an extensive soft tissue defect which was closed with a reverse latissimus muscle flap after traumatic spinal epidural hemorrhage.

Comparison of efficacy for erectile function and lower urinary tract symptoms of tadalafil 20 mg on-demand and 5 mg once daily in patients with erectile dysfunction

Aim:  To compare the improvement in erectile dysfunction (ED) and lower urinary tract symptoms (LUTS) as well as safety of tadalafil dosed at 20 mg on-demand and 5 mg once daily among ED patients. Materials and methods:  A total of 194 ED patients visited between March 2010 and June 2011 were recruited. Out of 194 individuals, 168 (86.6%) met inclusion criteria after completing the two-week screening period (V0). The Patients were randomly allocated into two groups: (i) 20 mg of tadalafil as needed (Group 1: n = 84, 50.0%) and (ii) 5 mg of tadalafil once daily (Group 2: n = 84, 50.0%). Blood pressure (BP), heart rate (HR) and the five-item version of the International Index of Erectile Function (IIEF-5) were assessed immediately before initiation of treatment (V1) and after four (V2) and twelve weeks of treatment (V3). In men with an IPSS of ≥ 8 at V1, IPSS, maximal flow rate (Qmax) and post-void residual volume (PVR) were also assessed. Results:  Of the 168 patients, 134 (79.8%; Group 1: n = 68, 81.0%; Group 2: n = 66, 78.6%) patients completed the trial. IIEF-5 improved in both groups, and the mean change was larger in Group 2 at V3 (4.9 ± 4.2 vs. 6.5 ± 4.5; p = 0.032) Similarly, though IPSS (with ≥ 8, n = 88, 65.7%; Group 1: n = 44, 64.7%; Group 2: n = 44, 66.7%) improved in both groups, the mean change was larger in Group 2 at V3 (-2.8 ± 4.3 vs. -4.8 ± 4.1; p = 0.026). Qmax and PVR did not differ significantly in either group. Conclusions:  Once daily tadalafil was more efficacious in treating both ED and LUTS than on-demand dosing. However, no differences were observed between the two dosing schedules with regard to the improvement in LUTS when stratified by improvement in ED. The side effects were insignificant for both dosing schedules.

Development and evaluation of a new device to effectively detach micro-organisms from food samples

AIMS

 To develop a new instrument of great versatility for recovering micro-organisms from all types of food samples and to compare the effects with existing sample preparation methods.

METHODS AND RESULTS

 To detach micro-organisms from large-size unbroken food samples such as apples, carrots, potatoes and tomatoes without preprocessing, the Spindle apparatus was newly developed. The Spindle was used to effectively detach micro-organisms from large-size samples. In a comparative study involving 51 food samples, treatment with the Spindle and Stomacher showed that recovery of total aerobic micro-organisms (naturally occurring mesophilic microflora) and foodborne pathogens (from samples inoculated with Escherichia coli O157:H7, Salmonella Typhimurium and Listeria monocytogenes) for both methods was highly correlated (R² = 0·98). Furthermore, diluents treated by the Spindle contained much less food debris than those treated by stomaching.

CONCLUSIONS

 These results indicate that Spindle is a novel, effective alternative method for detaching micro-organisms from food samples including four kinds of large-size samples without the need for preprocessing.

SIGNIFICANCE AND IMPACT OF STUDY

 The Spindle might be used to widely detaching micro-organisms from all types of food samples for microbiological assay.

Isolation and characterization of a lytic Myoviridae bacteriophage PAS-1 with broad infectivity in Aeromonas salmonicida

To search for candidate control agents against Aeromonas salmonicida subsp. salmonicida infections in aquaculture, one bacteriophage (phage), designated as PAS-1, was isolated from the sediment samples of the rainbow trout (Oncorhynchus mykiss) culture farm in Korea. The PAS-1 was morphologically classified as Myoviridae and possessed approximately 48 kb of double-strand genomic DNA. The phage showed broad host ranges to other subspecies of A. salmonicida as well as A. salmonicida subsp. salmonicida including antibiotic-resistant strains. Its latent period and burst size were estimated to be approximately 40 min and 116.7 PFU/cell, respectively. Furthermore, genomic and structural proteomic analysis of PAS-1 revealed that the phage was closely related to other Myoviridae phages infecting enterobacteria or Aeromonas species. The bacteriolytic activity of phage PAS-1 was evaluated using three subspecies of A. salmonicida strain at different doses of multiplicity of infection, and the results proved to be efficient for the reduction of bacterial growth. Based on these results, PAS-1 could be considered as a novel Aeromonas phage and might have potentiality to reduce the impacts of A. salmonicida infections in aquaculture.

Inferolateral entry point for c2 pedicle screw fixation in high cervical lesions

OBJECTIVE

The purpose of this retrospective study was to evaluate the efficacy and safety of atlantoaxial stabilization using a new entry point for C2 pedicle screw fixation.

METHODS

Data were collected from 44 patients undergoing posterior C1 lateral mass screw and C2 screw fixation. The 20 cases were approached by the Harms entry point, 21 by the inferolateral point, and three by pars screw. The new inferolateral entry point of the C2 pedicle was located about 3-5 mm medial to the lateral border of the C2 lateral mass and 5-7 mm superior to the inferior border of the C2-3 facet joint. The screw was inserted at an angle 30° to 45° toward the midline in the transverse plane and 40° to 50° cephalad in the sagittal plane. Patients received followed-up with clinical examinations, radiographs and/or CT scans.

RESULTS

There were 28 males and 16 females. No neurological deterioration or vertebral artery injuries were observed. Five cases showed malpositioned screws (2.84%), with four of the screws showing cortical breaches of the transverse foramen. There were no clinical consequences for these five patients. One screw in the C1 lateral mass had a medial cortical breach. None of the screws were malpositioned in patients treated using the new entry point. There was a significant relationship between two group (p=0.036).

CONCLUSION

Posterior C1-2 screw fixation can be performed safely using the new inferolateral entry point for C2 pedicle screw fixation for the treatment of high cervical lesions.

Is titanium mesh cage safe in surgical management of pyogenic spondylitis?

OBJECTIVE

To report our experience with pyogenic spondylitis treated with anterior radical debridement and insertion of a titanium mesh cage and to demonstrate the effectiveness and safety of the use of a titanium mesh cage in the surgical management of pyogenic spondylitis.

METHODS

We retrospectively analyzed the clinical characteristics of 19 patients who underwent surgical treatment in our department between January 2004 and December 2008. The average follow-up period was 11.16 months (range, 6-64 months). We evaluated risk factors, cultured organisms, lab data, clinical outcomes, and radiographic results. Surgical techniques for patients with pyogenic spondylitis were anterior radical debridement and reconstruction with titanium mesh cage insertion and screw fixation. All patients received intravenous antibiotics for at least 6 weeks postoperatively, and some patients received oral antibiotics.

RESULTS

The infections resolved in all of the patients as noted by normalization of their erythrocyte sedimentation rates and C-reactive protein levels. The mean pain score on a Visual Analog Scale was 7.8 (range, 4-10) before surgery and 2.4 (range, 1-5) after surgery. The Frankel grade was improved by one grade in seven patients. After surgery, the average difference of the angle was improved about 6.96° in all patients. At the last follow-up, the mean loss of correction was 4.86°.

CONCLUSION

Anterior radical debridement followed by the placement of instrumentation with a titanium mesh cage may be a safe and effective treatment for selected patients with pyogenic spondylitis. This surgical therapy does not lead to recurrent pyogenic spondylitis.

Nano-scaled Pt/Ag/Ni/Au contacts on p-type GaN for low contact resistance and high reflectivity

We synthesized the vertical-structured LED (VLED) using nano-scaled Pt between p-type GaN and Ag-based reflector. The metallization scheme on p-type GaN for high reflectance and low was the nano-scaled Pt/Ag/Ni/Au. Nano-scaled Pt (5 A) on Ag/Ni/Au exhibited reasonably high reflectance of 86.2% at the wavelength of 460 nm due to high transmittance of light through nano-scaled Pt (5 A) onto Ag layer. Ohmic behavior of contact metal, Pt/Ag/Ni/Au, to p-type GaN was achieved using surface treatments of p-type GaN prior to the deposition of contact metals and the specific contact resistance was observed with decreasing Pt thickness of 5 A, resulting in 1.5 x 10(-4) ohms cm2. Forward voltages of Pt (5 A)/Ag/Ni contact to p-type GaN showed 4.19 V with the current injection of 350 mA. Output voltages with various thickness of Pt showed the highest value at the smallest thickness of Pt due to its high transmittance of light onto Ag, leading to high reflectance. Our results propose that nano-scaled Pt/Ag/Ni could act as a promising contact metal to p-type GaN for improving the performance of VLEDs.

CT differentiation of pyogenic liver abscesses caused by Klebsiella pneumoniae vs non-Klebsiella pneumoniae

OBJECTIVE

Klebsiella pneumoniae is one of the organisms most commonly isolated from pyogenic liver abscesses in Asian populations. We compared CT findings in liver abscesses caused by K. pneumoniae with those caused by other bacterial pathogens.

METHODS

Of 214 patients with liver abscesses examined over a 5 year period, 129 patients with positive blood or aspirate cultures were enrolled. The patients were divided into two groups: the K. pneumoniae monomicrobial liver abscess (KLA) group (n = 59) and the non-K. pneumoniae monomicrobial or polymicrobial liver abscess (non-KLA) group (n = 70). Two radiologists blinded to the culture results evaluated the CT images, recording the number, size, location and configuration of abscesses, the thickness of the abscess wall, the pattern of rim enhancement, septal enhancement, the double target sign, internal necrotic debris, internal gas bubbles and underlying biliary disease. The presence of diabetes and metastatic infection was also compared between groups. Statistical analyses were performed using univariate (Student's t-test and χ(2) test) and multivariate analyses.

RESULTS

Multivariate analysis showed that a thin wall, necrotic debris, metastatic infection and the absence of underlying biliary disease were the most significant predictors of KLA. When three of the four criteria were used in combination, a specificity of 98.6% was achieved for the diagnosis of KLA.

CONCLUSION

A thin-walled abscess, internal necrotic debris, the presence of metastatic infection and the absence of underlying biliary disease may be useful CT findings in the early diagnosis of K. pneumoniae liver abscesses.

Posterior atlantoaxial screw-rod fixation in a case of aberrant vertebral artery course combined with bilateral high-riding vertebral artery

We present a case of posterior atlantoaxial screw-rod fixation in a patient with an aberrant vertebral artery (VA) course combined with bilateral high-riding VA. An aberrant VA which courses below the posterior arch of the atlas (C1) that does not pass through the C1 transverse foramen and without an osseous anomaly is rare. However, it is important to consider an abnormal course of the VA both preoperatively and intraoperatively in order to avoid critical vascular injuries in procedures which require exposure or control of the VA, such as the far-lateral approach and spinal operations.

Eight enrichment broths for the isolation of Campylobacter jejuni from inoculated suspensions and ground pork

AIMS

The efficiency of eight enrichment broths for the selective isolation of Campylobacter jejuni was compared to identify an optimal enrichment broth.

METHODS AND RESULTS

Brucella-FBP, Preston, Doyle and Roman, modified CCD (mCCD), Park and Sanders, Bolton, Hunt and Radle and Hunt broths were compared for their recovery of (i) Camp. jejuni in suspension, (ii) Camp. jejuni from inoculated ground pork, (iii) heat-injured Camp. jejuni (55 degrees C for 20 min) in suspension and (iv) heat-injured Camp. jejuni from inoculated ground pork. Hunt broth and Bolton broth showed the highest and most rapid enrichment efficacy for the cell suspensions and ground pork, respectively. Preston, Park and Sanders and mCCD broths had relatively high enrichment efficiencies, while Brucella-FBP broth was significantly inferior to the other broths (P < 0.05).

CONCLUSIONS

Cell recovery from the eight enrichment broths was dependent on the sample type and the state of the cells. The use of the appropriate broth is important for the rapid and efficacious enrichment of Camp. jejuni. In particular, heat-injured Camp. jejuni require a longer cultivation time and a suitable enrichment broth.

SIGNIFICANCE AND IMPACT OF THE STUDY

The results from the present study provide information for selecting the most appropriate enrichment broth for Camp. jejuni and may contribute to improved detection methods for the organism.