Eun-Min Seo

The Influence of Thoracic Inlet Alignment on the Craniocervical Sagittal Balance in Asymptomatic Adults

Study Design: A prospective radiographic study. Objectives: To analyze the relationship between craniocervical sagittal balance and thoracic inlet (TI) alignment and to present the parameters that would help predict physiological lordosis of the cervical spine. Summary of Background Data: The physiological cervical lordosis (CL) and related factors has not been clearly defined yet. No studies have reported correlations between TI alignment and sagittal balance of the cervical spine. Methods: Cervical spine lateral radiograph of 77 asymptomatic adult volunteers (aged between 21 and 50 y) were taken to analyze the following parameters. (1) Thoracic inlet parameters: thoracic inlet angle (TIA), T1 slope, neck tilting (NT); (2) cervical spine parameters: C0-2 angle, C2-7 angle, % ratio of (C0-2/C0-7 angle), (C2-7/C0-7 angle), and cervical tilting; (3) cranial parameters: C0 angle, cranial offset, and cranial tilting. Statistical analysis was performed using the Pearson correlation coefficients and multiple regression analysis. Results: The mean TIA, T1 slope, NT were 69.5, 25.7, and 43.7, respectively. The mean C0-2 angle, C2-7 angle, C0 angle, cranial offset, cervical tilting, and cranial tilting were −22.4 degrees, −9.9 degrees, −9.3 degrees, 20.9 mm, 18 degrees, and 7.7 degrees, respectively. The ratio of C0-2:C2-7 angle was maintained as 77:23% and cervical tilting:cranial tilting was 70.2:29.8%. A significant correlation was found between TIA and T1 slope (r=0.694), T1 slope and C2-7 angle (r=−0.624), C2-7 angle and C0-2 angle (r=−0.547), C0-2 angle and cranial offset (r=−0.406). Conclusions: The thoracic inlet alignment had significant correlations with craniocervical sagittal balance. To preserve physiological NT around 44 degrees, large TIA increased T1 slope and CL and vice versa. TIA and T1 slope could be used as parameters to predict physiological alignment of the cervical spine. The results of this study may serve as baseline data for the evaluation of sagittal balance or planning of a fusion angle in the cervical spine.

Factors determining cervical spine sagittal balance in asymptomatic adults: correlation with spinopelvic balance and thoracic inlet alignment

BACKGROUND CONTEXT Based on the previous studies, cervical lordosis (CL) is a parameter influenced by thoracic kyphosis (TK); however, the correlations still remain unclear. Few studies have analyzed the correlations between the cervical spine lordosis and global spinopelvic balance. To date, there has been no study focused on the factors determining cervical spine sagittal balance. PATIENT SAMPLE Seventy-seven asymptomatic volunteers without the history of symptoms related to whole spine. OUTCOME MEASURES Statistical significance of correlations of radiographic parameters on cervical spine and whole-spine standing lateral radiograph. PURPOSE To analyze the factors determining cervical spine sagittal balance, including global spinopelvic balance and thoracic inlet (TI) alignment in asymptomatic adults. STUDY DESIGN A prospective radiographic study. METHODS Cervical and whole-spine standing lateral radiographs were taken to analyze the following parameters: spinopelvic parameters pelvic incidence (PI), sacral slope (SS), lumbar lordosis (LL), and TK; TI parameters thoracic inlet angle (TIA) and T1 slope; and cervical spine parameters C0-C2, C2-C7, and C0-C7 angles and cervical tilting. Statistical analysis was performed using the Pearson correlation coefficients and multiple regression analysis. RESULTS All the parameters showed a normal distribution. There was a significant sequential linkage between PI and SS (r=0.653), SS and LL (r=0.807), LL and TK (r=-0.516), and TK and C0-C7 angle (r=-0.322). There was a significant relationship between TK and T1 slope (r=0.351) but no significant relationship between TK and TIA. There were significant sequential relationships between TIA and T1 slope (r=0.694), T1 slope and C2-C7 angle (r=-0.624), and C2-C7 and C0-C2 angles (r=-0.547). T1 slope was the only parameter that demonstrated a significant correlation with both SP and TI parameters. A linear regression model showed that T1 slope had a stronger relationship with TIA (r=0.694) than TK (r=0.351). CONCLUSIONS T1 slope was a key factor determining cervical spine sagittal balance. Both spinopelvic balance and TI alignment have a significant influence on cervical spine sagittal balance via T1 slope, but TIA had a stronger effect than TK. An individual with large T1 slope required large CL to preserve physiologic sagittal balance of the cervical spine. The results of the present study could serve as baseline data for further studies on the cervical spine sagittal balance in various clinical conditions including the surgical reconstruction of lordosis.

Regulation of Wnt signaling activity for growth suppression induced by quercetin in 4T1 murine mammary cancer cells

Quercetin is a promising chemopreventive agent against cancer that inhibits tumor progression by inducing cell cycle arrest and promoting apoptotic cell death. Recently, the Wnt/β-catenin signaling pathway has been implicated in mammary tumorigenesis, where its abnormal activation is associated with the development of breast cancer. Thus, the objective of this study was to examine the biological activities of quercetin against mammary cancer cells, and to determine whether quercetin could regulate the Wnt/β-catenin signaling pathway. Quercetin showed dose-dependent inhibition of cell growth and induced apoptosis in 4T1 cells. Treatment of 20 µM quercetin suppressed ~50% of basal TopFlash luciferase activity. Moreover, the inhibitory effect of quercetin on the Wnt/β-catenin signaling pathway was confirmed by the reduced stabilization of the β-catenin protein. Among various antagonists screened for the Wnt/β-catenin signaling pathway, the expression of DKK1, 2 and 3 was induced after treatment with 20 µM of quercetin. Stimulation with recombinant DKK1 protein, showed suppressive cell growth of mammary cancer cells instead of quercetin. When 4T1 cells were treated with recombinant Wnt3a or LiCl along with quercetin, both stimulators for the Wnt/β-catenin signaling pathway were able to restore the suppressed cell viability by quercetin. Thus, our data suggest that quercetin exerts its anticancer activity through the downregulation of Wnt/β-catenin signaling activity. These results indicate for the first time that quercetin decreases cell viability and induces apoptosis in murine mammary cancer cells, which is possibly mediated by DKK-dependent inhibition of the Wnt/β-catenin signaling pathway. In conclusion, our findings suggest that quercetin has great potential value as chemotherapeutic agent for cancer treatment, especially in breast cancer controlled by Wnt/β-catenin signaling activity.

Sagittal decompensation after corrective osteotomy for lumbar degenerative kyphosis: classification and risk factors.

Study Design. A retrospective study Objective. To classify the types and identify related factors on sagittal decompensation after corrective osteotomy for lumbar degenerative kyphosis (LDK). Summary of Background Data. There has been a skeptical view of surgical treatment of LDK owing to loss of sagittal balance even after correction of kyphosis. However, there had been no report on the classification and risk factors of sagittal decompensation. Methods. A total of 23 LDK patients who had undergone corrective osteotomy were enrolled. The mean follow-up period was 45.7 months. Radiographic parameters including sagittal balance, the cross-sectional area of paravertebral muscles, were analyzed. We classified the type of sagittal decompensation into thoracic (Group T) and lumbar decompensation (Group L) with a reference line from the posterosuperior corner of the sacrum to the center of the T12-L1 disc. The type of sagittal decompensation was defined with the location of T1 and the reference line at the last follow-up radiographs. Results. The mean number of fusion segments was 7.7. Sagittal balance improved from 26.4 cm to 4 cm immediately after operation but deteriorated to 11.2 cm at the last follow-up. The decompensation was greater in Group T (11 cases) than in Group L (12 cases) (9.1 cm vs. 5.2 cm, P = 0.03). The comparative analysis showed significant differences between groups T and L in thoracic kyphosis at the last follow-up (Group T:L = 40.5°:27.5°, P = 0.04), preoperative thoracic kyphotic angle (Group T:L = 19.6°:−1°, P = 0.01), mean ratio of cross-sectional area of paravertebral muscles to intervertebral disc in T12-L1, and incidence of the preoperative compensatory thoracic lordosis (Group T:L = 27.3%:100%, P = 0). Conclusion. The mean sagittal decompensation after corrective osteotomy for LDK was 38.3%. The etiology was loss of lumbosacral lordosis in Group L and progression of kyphosis at the proximal unfused segments in addition to lumbosacral loss in Group T. The decompensation was greater in the thoracic type than in the lumbar type and was considered relevant to a large preoperative thoracic kyphotic angle, absence of compensatory thoracic lordosis, and atrophy of paravertebral muscles.

Cervical Pedicle Screw Insertion Using the Technique with Direct Exposure of the Pedicle by Laminoforaminotomy

Objective To present the accuracy and safety of cervical pedicle screw insertion using the technique with direct exposure of the pedicle by laminoforaminotomy. Methods We retrospectively reviewed 12 consecutive patients. A total of 104 subaxial cervical pedicle screws in 12 patients had been inserted. We also assessed the clinical and radiological outcomes and analyzed the direction and grade of pedicle perforation (grade 0: no perforation, 1: <25%, 2: 20% to 50%, 3: >50% of screw diameter) on the postoperative vascular-enhanced computed tomography scans. Grade 2 and 3 were considered as incorrect position. Results The correct position was found in 95 screws (91.3%); grade 0-75 screws, grade 1-20 screws and the incorrect position in 9 screws (8.7%); grade 2-6 screws, grade 3-3 screws. There was no neurovascular complication related with cervical pedicle screw insertion. Conclusion This technique (technique with direct exposure of the pedicle by laminoforaminotomy) could be considered relatively safe and easy method to insert cervical pedicle screw.

Lumbosacral spondyloptosis treated using partial reduction and pedicular transvertebral screw fixation in an osteoporotic elderly patient

Spondyloptosis is complete dislocation of the L-5 vertebral body on the sacrum anteriorly. Its optimal treatment is still controversial. In particular, choosing the optimal surgical technique is difficult in the osteoporotic elderly patient given the high incidence of instrumentation failure, pseudarthrosis, progressive slippage, and severe sagittal imbalance. The authors of this report used partial reduction and pedicular transvertebral screw fixation of the lumbosacral junction for the treatment of spondyloptosis in an osteoporotic elderly patient.

DNA barcoding to fishes: current status and future directions

Abstract DNA barcoding appears to be a promising approach for taxonomic identification, characterization, and discovery of newer species, facilitating biodiversity studies. It helps researchers to appreciate genetic and evolutionary associations by collection of molecular, morphological, and distributional data. Fish DNA barcoding, based on the sequencing of a uniform area of Cytochrome C Oxidase type I (COI) gene, has received significant interest as an accurate tool for species identification, authentication, and phylogenetic analysis. The aim of this review article was to investigate recent global status, approaches, and future direction of DNA barcoding in fisheries sectors. We have tried to highlight its possible impacts, complications, and validation issues at species levels for biodiversity analysis. Moreover, an effort has been put forward to understand issues related to various marker genes associated with barcode process as primer sequences and have concluded barcode promotion as an indispensable tool of molecular biology for the development of taxonomic support systems.

The safety zone of percutaneous cervical approach: a dynamic computed tomographic study.

Study Design. A prospective study using computed tomography (CT) scans. Objective. To identify the structures at risk and the safety zone of a percutaneous cervical approach. Summary of Background Data. A percutaneous cervical approach may injure the important structures of the anterior neck. However, the dynamic locations of vital structures and the structures at risk by routine trajectory have not been analyzed. Methods. Thirty patients were enrolled for this study. We obtained the CT scans of the cervical spine at each level of the intervertebral disc from C3–C4 to C6–C7, after manually pushing the airway in the same position and manner of discography. The patients ingested contrast materials for imaging of their digestive tracts and were injected intravenous contrast materials for imaging of vascular structures, just before obtaining images. We estimated the distances from the operators fingertip to the digestive tract on the left side and to the carotid artery on the right side, at each level. The safety zone was determined by the sum of 2 distance calculations. We identified the anatomic structure at risk by simulated needle insertion toward the center of the disc through the safety zone. Results. At C3–C4, the safety zone was measured 18.9 ± 6.6 mm. The superior thyroidal artery (STA) was located in the safety zone of C3–C4 in 86.7%. At C4–C5, the safety zone was measured 23.5 ± 6.5 mm. The STA and the right lobe of the thyroid gland (TG) were located in the safety zone in 26.7% and 30%, respectively. At C5–C6, the safety zone was measured 33.7 ± 6 mm. The TG was located in the safety zone of C5–C6 in 76.7%. At C6–C7, the safety zone was 29.2 ± 4.5 mm. The TG was located on the approach plane in 90%. Conclusion. The safety zone was wider at the distal level (C5–C6, C6–C7) than at the proximal level (C3–C4, C4–C5). The safest needle entry point should be between the pushing point of the airway and the pulsating point of the carotid artery. In addition, the needle should be approached toward the center of the disc. A percutaneous cervical approach allows a low risk of pharyngoesophageal structure injury and is considered a safe diagnostic technique in dynamic imaging studies.

Genetic Polymorphism in Extracellular Regulators of Wnt Signaling Pathway

The Wnt signaling pathway is mediated by a family of secreted glycoproteins through canonical and noncanonical mechanism. The signaling pathways are regulated by various modulators, which are classified into two classes on the basis of their interaction with either Wnt or its receptors. Secreted frizzled-related proteins (sFRPs) are the member of class that binds to Wnt protein and antagonizes Wnt signaling pathway. The other class consists of Dickkopf (DKK) proteins family that binds to Wnt receptor complex. The present review discusses the disease related association of various polymorphisms in Wnt signaling modulators. Furthermore, this review also highlights that some of the sFRPs and DKKs are unable to act as an antagonist for Wnt signaling pathway and thus their function needs to be explored more extensively.

Charcot Spine Treated Using a Single Staged Posterolateral Costotransversectomy Approach in a Patient with Traumatic Spinal Cord Injury

Charcot spine is a progressive and destructive process that affects the vertebral bodies, intervertebral discs, and posterior facets. It is the result from repetitive microtrauma in patients who have decreased joint protective mechanisms due to loss of deep pain and proprioceptive sensation, typically because of spinal cord injury. The objective of the study is to report an unusual case of Charcot spine, as a late complication of traumatic spinal cord injury, treated by a circumferential arthrodesis performed with a single staged posterolateral costotransversectomy approach.