The present study analyzed the risk factors, prevalence and clinical results following revision surgery for adjacent segment degeneration (ASD) in patients who had undergone lumbar fusion.
Over an 8-year period, we performed posterior lumbar fusion in 81 patients. Patients were followed a minimum of 2 years (mean 5.5 years). During that time, 9 patients required revision surgery due to ASD development. Four patients underwent autogenous posterolateral arthrodesis and extended transpedicle screw fixation, 4 patients underwent decompressive laminectomy and interspinous device implantation, and 1 patient underwent simple decompression.
Of the 9 of patients with clinical ASD, 33.3% (3 of 9) of patients did not have radiographic ASD on plain radiographs. Following revision surgery, the clinical results were excellent or good in 8 patients (88.9%). Age > 50 years at primary surgery was a significant risk factor for ASD development, while number of fusion levels, initial diagnosis and type of fusion were not.
The incidence of ASD development after lumbar surgery was 11.1% (9 of 81) in this study. Age greater than 50 was the statistically significant risk factor for ASD development. Similar successful clinical outcomes were observed after extended fusion with wide decompression or after interspinous device implantation. Given the latter procedure is less invasive, the findings suggest it may be considered a treatment alternative in selected cases but it needs further study.
Adjacent segment degeneration; Risk factor; Fusion; Interspinous implant
A study is reported on the effect of nanowire density on the ease of pellicle formation and the enrichment of plasma membrane proteins for analysis by mass spectrometry. An optimized synthesis is reported for iron silicate nanowires with a narrow size range of 900 ±400 nm in length and 200 nm diameter. The nanowires were coated with Al2O3 and used to form pellicles around suspended multiple myeloma cells, which acted as a model for cells recovered from tissue samples. Lighter alumina-coated silica nanowires were also synthesized (Kim et al. 2013), which allowed a comparison of the construction of the two pellicles and of the effect of nanowire density on plasma membrane enrichment. Evidence is offered that the dense nanowire pellicle does not crush or distort these mammalian cells. Finally, the pellicles were incorporated into a mass-spectrometry-based proteomic workflow to analyze transmembrane proteins in the plasma membrane. In contrast to a prior comparison of the effect of density with nanoparticles pellicles (Choksawangkarn et al. 2013), nanowire density was not found to significantly affect the enrichment of the plasma membrane. However, nanowires with a favorable aspect for pellicle formation are more easily and reliably produced with iron silicate than with silica. Additionally, the method for pellicle formation was optimized through the use of iron silicate nanowires (ISNW), which is crucial to the improvement of PM protein enrichment and analysis.
Plasma membrane enrichment; nanowire pellicles; nanowire cell coating; silica nanowires; iron silicate nanowires
Abnormalities of the posterior arch, including congenitally absent cervical pedicle and cervical spondylolysis, are rare entities that are usually found incidentally on neck radiographs. It is important to recognize these characteristic radiological features because their radiographic appearance may cause them to be confused with more serious entities such as fractures, locked facets, and tumor-induced bony erosions. Also, it is important to distinguish these abnormalities from similar pathologies to prevent the use of inappropriate treatment. We report the relevant clinical and radiological findings seen in three cases of posterior arch defect after trauma with review of pertinent literature.
Absent cervical pedicle; Cervical spondylolysis; Congenital abnormality
Craniovertebral junction (CVJ) consists of the occipital bone that surrounds the foramen magnum, the atlas and the axis vertebrae. The mortality and morbidity is high for irreducible CVJ lesion with cervico-medullary compression. In a clinical retrospective study, the authors reviewed clinical and radiographic results of occipitocervical fusion using a various methods in 32 patients with CVJ instability.
Thirty-two CVJ lesions (18 male and 14 female) were treated in our department for 12 years. Instability resulted from trauma (14 cases), rheumatoid arthritis (8 cases), assimilation of atlas (4 cases), tumor (2 cases), basilar invagination (2 cases) and miscellaneous (2 cases). Thirty-two patients were internally fixed with 7 anterior and posterior decompression with occipitocervical fusion, 15 posterior decompression and occipitocervical fusion with wire-rod, 5 C1-2 transarticular screw fixation, and 5 C1 lateral mass-C2 transpedicular screw. Outcome (mean follow-up period, 38 months) was based on clinical and radiographic review. The clinical outcome was assessed by Japanese Orthopedic Association (JOA) score.
Nine neurologically intact patients remained same after surgery. Among 23 patients with cervical myelopathy, clinical improvement was noted in 18 cases (78.3%). One patient died 2 months after the surgery because of pneumonia and sepsis. Fusion was achieved in 27 patients (93%) at last follow-up. No patient developed evidence of new, recurrent, or progressive instability.
The authors conclude that early occipitocervical fusion to be recommended in case of reducible CVJ lesion and the appropriate decompression and occipitocervical fusion are recommended in case of irreducible craniovertebral junction lesion.
Craniocervical junction instability; Occipitocervical fusion; Spinal instrumentation
Degenerated conditions such as herniated disc or spinal stenosis are common etiologies of lumbar radiculopathy. Less common etiologies include spinal extradural cyst such as synovial cysts and ganglion cysts. Ganglion cyst of the posterior longitudinal ligament (PLL) of the spine is a rare entity that can result in classical sciatica. Posterior longitudinal ligament cyst has no continuity with the facet joint and has no epithelial lining. Two young male patients presented with unilateral sciatica and were found to have intraspinal cystic lesions causing lumbar radiculopathy. Magnetic resonance imaging demonstrated rounded, cystic lesions (i.e., hypointense on T1- but hyperintense on T2-weighted images) adjacent to minimally dehydrated, nonherniated disc spaces in both cases. These patients underwent posterior decompression and cysts were excised, and their sciatic symptoms were completely resolved. Histological examination showed typical features of ganglion cysts in these cases.
Ganglion cyst; Intervertebral disc; Posterior longitudinal ligament
Nickel nanotubes have been synthesized by the popular and versatile method of template-assisted electrodeposition, and a surface-directed growth mechanism based on the adsorption of the nickel-borate complex has been proposed.
According to the development of endovascular technique and devices, larger aneurysms on the distal internal carotid artery (ICA) can be treated using a less invasive method. The authors report on clinical and angiographic outcomes of these aneurysms treated using an endovascular technique.
Materials and Methods
Data on 21 patients with large aneurysms at distal ICA treated by endovascular method between January 2005 and December 2012 were included in this retrospective analysis.
Clinical outcome of patients showed strong correlation with the initial neurologic status (p < 0.05). Aneurysm morphology showed saccular, fusiform, and wide-neck in 12, six and three patients. Six patients underwent stent assisted coiling and the other 15 patients underwent simple coiling. Aneurysm occlusion was performed immediately after embolization with near-complete (Raymond class 1-2) in 20 patients (95.2%) and incomplete (Raymond class 3) in one patient (4.8%). Delayed thrombotic occlusion occurred in two patients and their clinical result was fatal. Another five patients died in the hospital, from massive brain edema and/or increased intracranial pressure due to initial subarachnoid hemorrhage. Overall mortality was 30% (seven out of 21). Fatal complication related to the endovascular procedure occurred in two patients with thrombosis at middle cerebral artery (one with stent, the other without it).
Recent developed endovascular device and technique is safe enough and a less invasive method for distal large or giant aneurysms. Based on our analysis of the study, we suspect that coil embolization of large distal ICA aneurysms (with or without stenting) is effective and safe.
Large aneurysm; Internal carotid artery; Endovascular; Stent
Proteomic and other characterization of plasma membrane proteins is made difficult by their low abundance, hydrophobicity, frequent carboxylation and dynamic population. We and others have proposed that underrepresentation in LC-MS/MS analysis can be partially compensated by enriching the plasma membrane and its proteins using cationic nanoparticle pellicles. The nanoparticles increase the density of plasma membrane sheets and thus enhance separation by centrifugation from other lysed cellular components. Herein we test the hypothesis that the use of nanoparticles with increased densities can provide enhanced enrichment of plasma membrane proteins for proteomic analysis. Multiple myeloma cells were grown and coated in suspension with three different pellicles of three different densities and both pellicle coated and uncoated suspensions analyzed by high-throughput LC-MS/MS. Enrichment was evaluated by the total number and the spectral counts of identified plasma membrane proteins.
Plasma membrane; nanoparticles; pellicle enrichment; proteomics; spectral counting
The recent development of 1D barcode arrays has proved their capabilities to be applicable to highly multiplexed bioassays. This article introduces two magnetic decoding protocols for suspension arrays of shape-coded silica nanotubes to process multiplexed assays rapidly and easily, which will benefit the minimization and automation of the arrays.
In the first protocol, the magnetic nanocrystals are incorporated into the inner voids of barcoded silica nanotubes in order to give the nanotubes magnetic properties. The second protocol is performed by trapping the barcoded silica nanotubes onto streptavidin-modified magnetic beads.
The rapid and easy decoding process was demonstrated by applying the above two protocols to multiplexed assays, resulting in high selectivity. Furthermore, the magnetic bead-trapped barcode nanotubes provided a great opportunity to exclude the use of dye molecules in multiplexed assays by using barcode nanotubes as signals.
The rapid and easy manipulation of encoded carriers using magnetic properties could be used to develop promising suspension arrays for portable bioassays.
AAO; anodic aluminum oxide; barcode; bioassay; cancer marker; magnetic decoding; multiplex assay; silica nanotubes; suspension array
We present a simple and up-scalable method to produce highly repaired graphene oxide with a large surface area, by introducing spherical multi-layered graphene balls with empty interiors. These graphene balls are prepared via chemical vapor deposition (CVD) of Ni particles on the surface of the graphene oxides (GO). Transmission electron microscopy and Raman spectroscopy results reveal that defects in the GO surfaces are well repaired during the CVD process, with the help of nickel nanoparticles attached to the functional groups of the GO surface, further resulting in a high electrical conductivity of 18,620 S/m. In addition, the graphene balls on the GO surface effectively prevent restacking of the GO layers, thus providing a large surface area of 527 m2/g. Two electrode supercapacitor cells using this highly conductive graphene material demonstrate ideal electrical double layer capacitive behavior, due to the effective use of the outstanding electric conductivity and the large surface area.
Our objective was a retrospective assessment of the management modalities that provided the most beneficial treatment in hemorrhagic moyamoya disease during the last 13 years at our institution. The clinical results of 44 patients with hemorrhagic moyamoya disease were investigated, comparing revascularization surgery (direct, indirect, and combined bypass) or conservative treatment. Angiographic features, rebleeding, and clinical outcome were investigated. Six of the 35 patients (17.1%) with revascularization surgery experienced rebleeding, as did 4 of 9 patients (44.4%) with conservative treatment. However, patients who underwent bypass surgery had a lower chance of rebleeding. No significant difference in chance of rebleeding was observed between bypass surgery and non surgery groups (p > 0.05). Cerebral angiography performed after bypass surgery showed that for achieving good postoperative revascularization, direct and combined bypass methods were much more effective (p < 0.05). While the risk of rebleeding in the revascularization group was generally lower than in the conservative treatment group, there was no statistically significant difference between treatment modalities and conservative treatment. Although statistical significance was not attained, direct and combined bypass may reduce the risk of hemorrhage more effectively than indirect bypass.
Hemorrhagic moyamoya disease; Revascularization surgery; Intracranial hemorrhage; Surgical results
In the present study, we evaluated the effect, safety and radiological outcomes of cervical hybrid surgery (cervical disc prosthesis replacement at one level, and interbody fusion at the other level) on the multilevel cervical degenerative disc disease (DDD).
Fifty-one patients (mean age 46.7 years) with symptomatic multilevel cervical spondylosis were treated using hybrid surgery (HS). Clinical [neck disability index (NDI) and Visual Analogue Scale (VAS) score] and radiologic outcomes [range of motion (ROM) for cervical spine, adjacent segment and arthroplasty level] were evaluated at routine postoperative intervals of 1, 6, 12, 24 months. Review of other similar studies that examined the HS in multilevel cervical DDD was performed.
Out of 51 patients, 41 patients received 2 level hybrid surgery and 10 patients received 3 level hybrid surgery. The NDI and VAS score were significantly decreased during the follow up periods (p<0.05). The cervical ROM was recovered at 6 and 12 month postoperatively and the mean ROM of inferior adjacent segment was significantly larger than that of superior adjacent segments after surgery. The ROM of the arthoplasty level was preserved well during the follow up periods. No surgical and device related complications were observed.
Hybrid surgery is a safe and effective alternative to fusion for the management of multilevel cervical spondylosis.
Multilevel cervical spondylosis; Anterior cervical discectomy and fusion; Total disc replacement; Hybrid
Engineered nanoparticles are one of the leading nanomaterials currently under investigation due to their applicability in various fields, including drug and gene delivery, biosensors, cancer treatment and diagnostic tools. Moreover, the number of commercial products containing nanoparticles released on the market is rapidly increasing. Nanoparticles are already widely distributed in air, cosmetics, medicines and even in food. Therefore, the unintended adverse effect of nanoparticle exposure is a growing concern both academically and socially. In this context, the toxicity of nanoparticles has been extensively studied; however, several challenges are encountered due to the lack of standardized protocols. In order to improve the experimental conditions of nanoparticle toxicity studies, serious consideration is critical to obtain reliable and realistic data. The cell type must be selected considering the introduction route and target organ of the nanoparticle. In addition, the nanoparticle dose must reflect the realistic concentration of nanoparticles and must be loaded as a well-dispersed form to observe the accurate size- and shape-dependent effect. In deciding the cytotoxicity assay method, it is important to choose the appropriate method that could measure the toxicity of interest without the false-negative or -positive misinterpretation of the toxicity result.
agglomeration; cell type; cytotoxicity assay; dose; nanoparticle; toxicity
Treatment for intoxication involves the neutralization or clearance of a toxic compound, but the current methods of treatment are limited in their ability to safely and effectively detoxify the patient. Emerging research has focused on using nanoparticles as parenteral detoxifying agents to circulate through the body and capture toxins. The variable compositions of these nanoparticles control the mechanism in which they capture and remove specific compounds. As discussed in this article, the recent methods for utilizing nanoparticles for detoxification show great potential for intoxication treatment. However, several challenges must be overcome before a universal nanoparticle detoxification method is available for clinical use.
detoxification; drug; liposomes; nanocapsules; nanomedicine; nanoparticles; overdose treatment; silica nanotubes; toxicity; uptake
Glutamate-induced cobalt uptake reveals that non-NMDA glutamate receptors (GluRs) are present in rat taste bud cells. Previous studies involving glutamate induced cobalt staining suggest this uptake mainly occurs via kainate type GluRs. It is not known which of the 4 types of taste bud cells express subunits of kainate GluR. Circumvallate and foliate papillae of Sprague-Dawley rats (45~60 days old) were used to search for the mRNAs of subunits of non-NMDA GluRs using RT-PCR with specific primers for GluR1-7, KA1 and KA2. We also performed RT-PCR for GluR5, KA1, PLCβ2, and NCAM/SNAP 25 in isolated single cells from taste buds. Taste epithelium, including circumvallate or foliate papilla, express mRNAs of GluR5 and KA1. However, non-taste tongue epithelium expresses no subunits of non-NMDA GluRs. Isolated single cell RT-PCR reveals that the mRNAs of GluR5 and KA1 are preferentially expressed in Type II and Type III cells over Type I cells.
Taste bud; Kainate receptor; RT-PCR; Single isolated cell
C2 laminar screw fixation is considered as an excellent alternative to Magerl's transfacetal approach or Harms construct for the atlantoaxial stabilization. However, to our knowledge, there is no report on the feasibility of the new approach to Korean population. We investigated morphometric parameters of the dorsal arch of the C2 to provide the quantitative data for the feasibility of laminar screw fixation.
One-hundred-and-two patients' cervical computed tomography had been reconstructed and investigated on the anatomical parameters related with C2 laminar screw placement. Sixty patients were male and forty-two patients were female. Measurements included the laminar thickness and slope, spino-laminar angle, and maximal screw length.
Ages ranged from 20 to 81 and the mean age was 48.4. Mean laminar thickness was 5.7 mm (±1.0) (5.8 mm in male and 5.4 mm in female). Fifty-one patients (50%) had a laminar thickness smaller than 5.5 mm at least unilaterally, therefore the patients were considered as inappropriate candidates for the laminar screw fixation in the smaller side of the laminae. Mean value of maximal length of screw was 33.3 mm (34.3 mm in male and 31.9 mm in female). Mean spino-laminar angle was 43.2° and mean slope angle was 32.9°.
Half of patients had inappropriate laminar profiles to accommodate a 3.5 mm screw in at least one side of the axis. The three-dimensional computed tomography reconstruction is mandatory for the preoperative assessment for the feasibility of the C2 lamina.
Axis; Laminar screw