Clinical outcomes of short rod technique in posterior lumbar interbody fusion surgery: a minimum of 2-year follow-up.

PURPOSE: We present for the first time a novel entry point of pedicle screws (Short Rod Technique, SRT), which can avoid superior facet violation and has been verified as a safe screw placement method. The purpose of this study is to determine the clinical outcomes of SRT in posterior lumbar interbody fusion (PLIF) surgery. METHODS: We retrospectively analyzed the clinical outcomes of 89 patients who received SRT and 109 patients who received PLIF surgery with regular entry points of pedicle screws with a minimum of 2 years of follow-ups. Patients were divided into three groups according to the number of fusion segments, and the clinical outcomes of the three groups were compared. RESULTS: The length of the wound and the length of rods were significantly shorter in the each SRT group. Less intraoperative blood loss was observed in the SRT group in patients with a single segment and two segments fusions, but not in three segments fusions. Fewer degenerations of the upper adjacent segment were observed in the SRT group in patients with a single segment and three segments fusions. In addition, less postoperative wound pain related to PLIF surgery was observed in the SRT group in patients with two and three segments fusions. CONCLUSION: SRT has been validated as an effective technique with good clinical outcomes, especially for reducing the occurrence of upper ASD in PLIF surgery with a single segment and three segments. The present study provides spinal surgeons with a novel method for performing PLIF surgery.

A novel ferroptosis-related microRNA signature with prognostic value in osteosarcoma.

The induction of ferroptosis is suggested to be a potential therapeutic strategy for cancers. MicroRNAs (miRNAs) are reported to play an important role in cell death processes. This study aims to construct and validate a risk model based on ferroptosis-related miRNAs (FR_miRNAs) to predict prognosis and identify novel therapeutic targets for osteosarcoma. Data from the Therapeutically Applicable Research to Generate Effective Treatments database are used as the training cohort. A prognostic signature based on two FR_miRNAs (miR-635 and miR-593) is developed using univariate Cox regression, least absolute shrinkage and selection operator regression, and multivariate Cox regression analyses. The area under the curve values of the prognostic signature to predict the 1-year, 2-year, 3-year, and 5-year overall survival rates in patients with osteosarcoma are 0.782, 0.781, 0.722, and 0.777, respectively, indicating a good predictive ability. Based on the risk score, patients are divided into low-risk and high-risk groups. Patients with high-risk scores are associated with poor survival. The risk level is determined to be an independent prognostic factor. A nomogram is established for predicting prognosis. The expression levels of PRNP (miR-635-related ferroptosis-related gene (FRG); P=0.024) and HILPDA (miR-593-related FRG; P=0.025) are significantly different between the low-risk and high-risk groups. All results are validated in an external cohort (GSE39040). The results of the functional assay reveal that miR-635 mimics inhibit osteosarcoma (OS) cell proliferation and migration, whereas miR-593 overexpression exerts the opposite effect. In conclusion, miR-635 and miR-593 exert contrasting regulatory effects on OS cell proliferation and migration.

Effects of "fixation-fusion" sequence of lumbar surgery on surgical outcomes for patients with lumbar spinal stenosis: study protocol for a multicenter randomized controlled trial.

BACKGROUND: New-onset neurological symptoms such as numbness and pain in lower extremities might appear immediately after conventional lumbar interbody fusion (LIF) surgery performed in patients with lumbar spinal stenosis. METHODS AND ANALYSIS: This is a multicenter, randomized, open-label, parallel-group, active-controlled trial investigating the clinical outcomes of modified LIF sequence versus conventional LIF sequence in treating patients with lumbar spinal stenosis. A total of 254 eligible patients will be enrolled and randomized in a 1:1 ratio to either modified LIF sequence or conventional LIF sequence group. The primary outcome measure is the perioperative incidence of new-onset lower extremity neurological symptoms, including new adverse events of pain, numbness, and foot drop of any severity. Important secondary endpoints include visual analogue scale (VAS) pain score and lumbar Japanese Orthopaedic Association (JOA) recovery rate. Other safety endpoints will also be evaluated. The safety set used for safety data analysis by the actual surgical treatment received and the full analysis set for baseline and efficacy data analyses according to the intent-to-treat principle will be established as the two analysis populations in the study. CONCLUSION: This study is designed to investigate the clinical outcomes of modified LIF sequences in patients with lumbar spinal stenosis. It aims to provide clinical evidence that the modified "fixation-fusion" sequence of LIF surgery is effective in treating lumbar spinal stenosis. TRIAL REGISTRATION: http://www.chictr.org.cn/index.aspx ID: ChiCTR2100048507.

RHOA inhibits chondrogenic differentiation of mesenchymal stem cells in adolescent idiopathic scoliosis.

PURPOSE: The etiology of adolescent idiopathic scoliosis (AIS) remains unclear. The chondrogenic differentiation of mesenchymal stem cells (MSCs) is important in AIS, and the Ras homolog gene family member A (RHOA) is associated with chondrogenesis. The purpose of this study was to explore the effect of RHOA on the chondrogenic differentiation of MSCs in AIS. METHODS: We isolated MSCs from patients with AIS (AIS MSCs) and individuals without AIS (control MSCs). The inhibitor Y27632 was used to inhibit the function of RHOA/ROCK signaling, and plasmid-based overexpression and siRNA-mediated knockdown were used to manipulate RHOA expression. CCK-8 was used to detect cell viability. The phosphorylation levels of LIMK1, MLC2 and cofilin were detected by Western blotting. The mRNA expression of aggrecan, SOX9, and COL2A1 were confirmed using RT-PCR. Immunofluorescence was used to analyze F-actin and collagen II. Alcian blue staining was performed to assess the secretion of glycosaminoglycans (GAGs). RESULTS: We found that RHOA was significantly upregulated in AIS MSCs, and the phosphorylation levels of LIMK1, MLC2, and cofilin were increased. The mRNA expressions of aggrecan, SOX9, and COL2A1 were notably reduced in AIS MSCs. However, these effects were abolished by Y27632 treatment and RHOA knockdown in AIS MSCs. In addition, RHOA knockdown in AIS MSCs increased the content of collagen II and GAGs. RHOA overexpression in the control MSCs markedly activated the RHOA/ROCK signaling and decreased the expression of aggrecan, SOX9, and COL2A1, F-actin, and GAGs. CONCLUSION: RHOA regulates the chondrogenic differentiation ability of MSCs in AIS via the RHOA/ROCK signaling pathway and this regulation may involve SOX9.

Sagittal imaging study of the lumbar spine with the short rod technique.

PURPOSE: The short rod technique (SRT) is a novel method for lumbar pedicle screw placement to reduce surgical trauma and avoid damage to the facet joint and articular surface. The core concept is to change the entry point and angle of the screw on the vertebrae at both ends in the sagittal plane to shorten the length of the longitudinal rods. The purpose of this study is to determine the sagittal screw angle (SSA) and its safe Maximum (MAX) value on each lumbar vertebra for the SRT and to observe the shortening effect on the longitudinal rods. METHODS: A total of 152 healthy adults were investigated by measuring the lumbar spine lateral view images. The SSA and MAX-SSA were measured with SRT as reference to the conventional placement technique method. The distance between the entry points of the proximal and distal vertebrae was measured to compare the changes in the length of the longitudinal rods using the two screw placement techniques. RESULTS: + SSA increased from L1 to L4, and -SSA increased from L2 to L5, in which the -SSA of L2, L3, and L4 were significantly greater than those of + SSA (P < 0.05). + MAX-SSA at L1-L4 was 23.26 ± 3.54°, 23.68 ± 3.37°, 24.12 ± 3.29°, and 24.26 ± 3.42°, respectively. -MAX-SSA at L2-L5 was 36.25 ± 3.26°, 38.26 ± 3.73°, 38.62 ± 3.63° and 37.33 ± 3.31°, respectively. Theoretical reductions by calculation for the 2-segment lumbar pedicles were: L1-2: 9 mm, L2-3: 9.29 mm, L3-4: 6.23 mm, and L4-5: 7.08 mm; And the 3-segment lumbar pedicles were: L1-3: 16.97 mm, L2-4: 16.73 mm, L3-5, and 18.24 mm, respectively. CONCLUSIONS: The application of the SRT to lumbar pedicles is a safe screw placement method that can significantly shorten the length of the used longitudinal rods.

Extracellular vesicles derived from CD73 modified human umbilical cord mesenchymal stem cells ameliorate inflammation after spinal cord injury.

BACKGROUND: Spinal cord injury (SCI) is an inflammatory condition, and excessive adenosine triphosphate (ATP) is released into the extracellular space, which can be catabolized into adenosine by CD73. Extracellular vesicles have been designed as nano drug carriers in many diseases. However, their impacts on delivery of CD73 after SCI are not yet known. We aimed to construct CD73 modified extracellular vesicles and explore the anti-inflammatory effects after SCI. METHODS: CD73 engineered extracellular vesicles (CD73+ hucMSC-EVs) were firstly established, which were derived from human umbilical cord mesenchymal stem cells (hucMSCs) transduced by lentiviral vectors to upregulate the expression of CD73. Effects of CD73+ hucMSC-EVs on hydrolyzing ATP into adenosine were detected. The polarization of M2/M1 was verified by immunofluorescence. Furthermore, A2aR and A2bR inhibitors and A2bR knockdown cells were used to investigate the activated adenosine receptor. Biomarkers of microglia and levels of cAMP/PKA were also detected. Repetitively in vivo study, morphology staining, flow cytometry, cytokine analysis, and ELISA assay, were also applied for verifications. RESULTS: CD73+ hucMSC-EVs reduced concentration of ATP and promoted the level of adenosine. In vitro experiments, CD73+ hucMSC-EVs increased macrophages/microglia M2:M1 polarization, activated adenosine 2b receptor (A2bR), and then promoted cAMP/PKA signaling pathway. In mice using model of thoracic spinal cord contusion injury, CD73+ hucMSC-EVs improved the functional recovery after SCI through decreasing the content of ATP in cerebrospinal fluid and improving the polarization from M1 to M2 phenotype. Thus, the cascaded pro-inflammatory cytokines were downregulated, such as TNF-α, IL-1ß, and IL-6, while the anti-inflammatory cytokines were upregulated, such as IL-10 and IL-4. CONCLUSIONS: CD73+ hucMSC-EVs ameliorated inflammation after spinal cord injury by reducing extracellular ATP, promoting A2bR/cAMP/PKA pathway and M2/M1 polarization. CD73+ hucMSC-EVs might be promising nano drugs for clinical application in SCI therapy.

An analysis of clinical risk factors for adolescent scoliosis caused by spinal cord abnormalities in China: proposal for a selective whole-spine MRI examination scheme.

BACKGROUND: Approximately 80% of adolescent scoliosis cases are idiopathic, and some non-idiopathic scoliosis cases caused by spinal cord abnormalities are misdiagnosed as idiopathic scoliosis. This study examined the risk factors for non-idiopathic scoliosis with intramedullary abnormalities, explored the feasibility of whole-spine MRI, and provided a theoretical basis for the routine diagnosis and treatment of adolescent idiopathic scoliosis. METHOD: The clinical data of adolescent scoliosis patients who were admitted to Shanghai Tongren Hospital and Shanghai Changhai Hospital between July 1, 2013, and December 31, 2018, were reviewed. According to the whole-spine MRI results, the patients were divided into either the idiopathic group or the intramedullary abnormality group. Sex, age, main curvature angle, main curvature direction, kyphosis angle, scoliosis type, coronal plane balance, sagittal plane balance, abdominal wall reflex, sensory abnormality, ankle clonus and tendon reflexes were compared between the two groups. Student's t test was used to evaluate the differences in the continuous variables, and the chi-square test was used to evaluate the differences in the categorical variables. Fisher's exact test was applied to detect the difference in the rate of intraspinal anomalies between the groups. Logistic regression was used to evaluate the correlation between the multivariate risk factors and intramedullary abnormalities. RESULT: A total of 714 adolescent scoliosis patients with a mean age of 13.5 (10-18 years) were included in the study, and intramedullary abnormalities were found in 68 (9.5%) patients. There were statistically significant differences in the incidence rates of intramedullary abnormalities between males and females, left and right thoracic curvatures, angular scoliosis and smooth scoliosis, and abnormal abdominal wall reflex and ankle clonus (P < 0.01). Logistic regression showed that the ratios for sex, scoliosis direction, scoliosis type, abdominal wall reflex and ankle clonus were 2.987, 3.493, 4.823, 3.94 and 8.083, respectively. The ROC curve showed a sensitivity of 66.18% and a specificity of 89.01%, and the Youden index corresponding to the optimal critical point was 0.5519. CONCLUSION: Risk factors associated with adolescent scoliosis caused by abnormal intramedullary abnormalities included male sex, thoracic scoliosis on the left side, sharp curvature of the spine, abnormal abdominal wall reflex and ankle clonus. In adolescent scoliosis patients, the incidence of scoliosis caused by intramedullary abnormalities was approximately 9.5%. These clinical indicators suggest that there is a high-risk adolescent scoliosis population who should undergo whole-spinal MRI preoperatively to rule out intramedullary abnormalities.

The programmed cell death 1 gene polymorphisms (PD 1.3 G/A, PD 1.5 C/T and PD 1.9 C/T) and susceptibility to ankylosing spondylitis: a meta-analysis.

OBJECTIVE: The objective is to integrate all the eligible studies and investigate whether the programmed cell death 1 (PDCD-1) gene polymorphisms (PD 1.3 G/A, PD 1.5 C/T, and PD 1.9 C/T polymorphism) are correlated with ankylosing spondylitis risk (AS). Ankylosing spondylitis is a chronic inflammatory disease, and several genetic and environmental factors play an important role in the development and progression of AS. Significant associations between PDCD-1 gene polymorphisms (PD 1.3 G/A, PD 1.5 C/T or PD 1.9 C/T) and AS risk have been reported; however, some of these results are controversial. METHODS: A systematic online search was performed using PubMed, EMBASE, Web of Science, and the Cochrane Library to identify case-control studies investigating the relationship between PD 1.3 G/A, PD 1.5 C/T, and PD 1.9 C/T polymorphisms and the susceptibility of AS. The pooled odds ratio (OR) with 95 % confidence interval (CI; 95 %) was calculated to assess the associations, and subgroup meta-analyses were performed according to the ethnicity of the study populations. RESULTS: Five studies involving 909 cases and 982 controls met the inclusion criteria after assessment by two reviewers. Overall, there were no significant associations between PD 1.3 G/A and PD 1.5 C/T polymorphisms and AS risk. With regard to PD 1.9 C/T polymorphism, a significant association was found under the allele contrast model (T vs. C: OR 1.74, 95 % CI 1.48-2.06, P < 0.001), heterozygote model (CT vs. CC: OR 2.43, 95 % CI 1.65-3.59, P < 0.001), homozygote model (TT vs. CC: OR 1.87, 95 % CI 1.30-2.71, P = 0.001), and dominant model (CT/TT vs. CC: OR 2.29, 95 % CI 1.65-3.18, P < 0.001). In the subgroup analysis of ethnicity, no significant associations were found between PD 1.3 G/A, PD 1.5 C/T polymorphisms, and AS risk in either Asian or Caucasian populations. However, our study suggested that PD 1.9 C/T polymorphism was significantly associated with AS in Asian populations (T vs. C: OR 1.72, 95 % CI 1.46-2.04, P < 0.001; CT vs. CC: OR 2.44, 95 % CI 1.56-3.82, P < 0.001; TT vs. CC: OR 1.88, 95 % CI 1.30-2.73, P = 0.001; and CT/TT vs. CC: OR 2.29, 95 % CI 1.58-3.32, P < 0.001) but not in Caucasian populations. CONCLUSION: The PD 1.9 C/T polymorphism may be involved in susceptibility to AS, particular in Asian populations; however, no significant associations were found between PD 1.3 G/A, PD 1.5 C/T polymorphisms, and AS risk in either Asians or Caucasians.

The polymorphisms of melatonin receptor 1B gene (MTNR1B) (rs4753426 and rs10830963) and susceptibility to adolescent idiopathic scoliosis: a meta-analysis.

OBJECTIVE: To determine whether MTNR1B rs4753426 and rs10830963 polymorphisms are correlated with AIS. Adolescent idiopathic scoliosis (AIS) is the most common form of spinal deformity, while its etiology remains uncertain. Melatonin receptor 1B (MTNR1B) gene polymorphisms have been found to be significantly associated with AIS risk; however, some of these results are controversial. METHODS: An systematic online search was performed using PubMed, EMBASE, Web of Science and the Cochrane Library to identify case-control studies investigating the relationship between MTNR1B rs4753426 and rs10830963 polymorphisms and the susceptibility of AIS. The pooled odds ratio (OR) with 95 % confidence interval (95 % CI) was calculated to assess the associations, and subgroup meta-analyses were performed according to the ethnicity of the study populations. RESULTS: A total of five studies involving 2395 cases and 3645 controls met the inclusion criteria after assessment by two reviewers. Overall, no significant associations were found between MTNR1B rs4753426 polymorphism and AIS risk (C vs. T: OR = 1.11, 95 % CI 0.94-1.30, P = 0.21; CC vs. TT: OR = 1.15, 95 % CI 0.97-1.36, P = 0.12; CT vs. TT: OR = 1.14, 95 % CI 0.97-1.35, P = 0.10; CC/CT vs. TT: OR = 1.14, 95 % CI 0.98-1.33, P = 0.09; CC vs. CT/TT: OR = 1.10, 95 % CI 0.84-1.45, P = 0.48), as well as the MTNR1B rs10830963 polymorphism (G vs. C: OR = 0.99, 95 % CI 0.88-1.12, P = 0.91; GG vs. CC: OR = 0.99, 95 % CI 0.74-1.33, P = 0.96; CG vs. CC: OR = 1.00, 95 % CI 0.84-1.18, P = 0.88; GG/CG vs. CC: OR = 0.99, 95 % CI 0.84-1.17, P = 0.93; GG vs. CG/CC: OR = 0.99, 95 % CI 0.75-1.30, P = 0.92). When stratified by ethnicity, there were no significant associations between MTNR1B rs4753426 and MTNR1B rs10830963 polymorphisms and AIS risk in either Asian or Caucasian populations. CONCLUSION: MTNR1B rs4753426 and MTNR1B rs10830963 polymorphisms are not obviously associated with risk of AIS in either Asian populations or Caucasian populations.

Application of the polystyrene model made by 3-D printing rapid prototyping technology for operation planning in revision lumbar discectomy.

OBJECTIVE: The objective was to evaluate the effectiveness of 3-D rapid prototyping technology in revision lumbar discectomy. 3-D rapid prototyping technology has not been reported in the treatment of revision lumbar discectomy. METHODS: Patients with recurrent lumbar disc herniation who were preparing to undergo revision lumbar discectomy from a single center between January 2011 and 2013 were included in this analysis. Patients were divided into two groups. In group A, 3-D printing technology was used to create subject-specific lumbar vertebral models in the preoperative planning process. Group B underwent lumbar revision as usual. Preoperative and postoperative clinical outcomes were compared between groups included operation time, perioperative blood loss, postoperative complications, Oswestry Disability Index (ODI), Japan Orthopaedics Association (JOA) scores, and visual analogue scale (VAS) scores for back pain and leg pain. RESULTS: A total of 37 patients were included in this study (Group A = 15, Group B = 22). Group A had a significantly shorter operation time (106.53 ± 11.91 vs. 131.92 ± 10.81 min, P < 0.001) and significantly less blood loss (341.67 ± 49.45 vs. 466.77 ± 71.46 ml, P < 0.001). There was no difference between groups for complication rate. There were also no differences between groups for any clinical metric. CONCLUSION: Using the 3-D printing technology before revision lumbar discectomy may reduce the operation time and the perioperative blood loss. There does not appear to be a benefit to using the technology with respect to clinical outcomes. Future prospective studies are needed to further elucidate the efficacy of this emerging technology.

(18)F-FDG PET/CT of adrenal lesions.

OBJECTIVE: The purpose of this review is to describe FDG uptake characteristics of adrenal lesions, which can show increased FDG uptake on PET/CT. CONCLUSION: Both benign and malignant adrenal lesions can show increased FDG uptake. Knowledge of the uptake characteristics of these lesions is helpful for increasing diagnostic accuracy and expanding the differential diagnosis for adrenal lesions.

Spectrum of the prostate lesions with increased FDG uptake on (18)F-FDG PET/CT.

OBJECTIVE: Increased FDG uptake in the prostate can be caused by both benign and malignant conditions. The purpose of this pictorial review is to demonstrate a spectrum of prostate lesions which can show increased FDG uptake on PET/CT imaging. CONCLUSION: Various prostate lesions can show increased FDG uptake. Knowledge of the uptake characteristics of these lesions may be helpful for increasing diagnostic accuracy.

Effect of lordosis angle change after lumbar/lumbosacral fusion on sacrum angular displacement: a finite element study.

PURPOSE: To assess and characterize the sacrum angular displacements in response to lumbar lordosis after lumbar/lumbosacral fusion. METHODS: A finite element model of the lower lumbar spine-pelvis was established and used to simulate the posterior fusion at L3-L5 and L4-S1. The lordosis angle in the fusion segments was set to five different conditions with respect to the intact model: 10° less than intact, 5° less than intact, same as intact, 5° more than intact, and 10° more than intact. Variations of the sacrum angular displacements with lordosis changes were analyzed under loading setting of axial compression, flexion, extension, lateral bending, and axial rotation. RESULTS: Compared with the intact lordosis, both increased and decreased lumbar lordosis angles caused the sacrum angular displacements to be increased. The lordosis angle increased by 10° induced the most substantial increase in sacrum angular displacements. In addition, the sacrum angular displacements of the L4-S1 fusion model at different lordosis angles were higher than those of the L3-L5 fusion model. CONCLUSION: The sacrum angular displacements occur as a result of the fusion surgery (L4-S1) and the changes in lumbar lordosis.

[Changhai fulcrum bending radiographic technique to assess curve flexibility in patients with adolescent idiopathic scoliosis].

OBJECTIVE: To evaluate the role and value of Changhai fulcrum bending radiograph(CH-FBR) in curve flexibility assessment of adolescent idiopathic scoliosis(AIS) patients. METHODS: Thirty-seven AIS patients treated between June 2012 and August 2013 were enrolled, including 31 female and 6 male patients whose age ranged from 10 to 19 years, averaged of 15.0 years. The assessment of radiographs included preoperative standing posterior-anterior radiograph, supine side-bending radiograph, traditional fulcrum bending radiograph, Changhai fulcrum bending radiograph and postoperative standing posterior-anterior radiograph. Postoperatively, radiographs were assessed at one week. The CH-FBR was performed at the lowest height and the optimized height which means the weight on the fulcrum touch the maximum. All measurements of angle were made with use of the Cobb method. The flexibility of the curve as well as the correction rate and fulcrum bending correction index (FBCI) were calculated for all patients. The maximum height of CH-FBR, basic weight and maximum weight were measured for all AIS. Paired t-tests were used to assess differences between preoperative and postoperative curves within group samples. The Pearson correlation coefficients were calculated using bivariate analysis between CH-FBR flexibility rate and correction rate, the maximum height of CH-FBR and maximum weight, the height changes of CH-FBR and weight changes. RESULTS: A total of 46 curves were involved in this study, including 28 thoracic and 18 thoracolumbar/lumbar curves. Preoperatively, the mean Cobb angle of the 46 structural curves was 47° ± 11°. Postoperatively, the mean Cobb angle was 11° ± 5°. Cobb's angle in supine side-bending(t = 7.2, P = 0.001), traditional fulcrum bending (t = 7.1, P = 0.001) and lowest height of Changhai fulcrum bending (t = 6.5, P = 0.001) were significantly different from the postoperative Cobb angle; Cobb's angle in traditional FBR (t = 11.0, P = 0.001) and lowest height of Changhai fulcrum bending (t = 13.6, P = 0.001) were significantly different from the optimized height CH-FBR Cobb angle. There was no significant difference found between traditional FBR Cobb angle and lowest height CH-FBR Cobb angle (t = 2.0, P = 0.051), optimized height CH-FBR Cobb angle and postoperative Cobb angle (t = 0.9, P = 0.36), lowest height CH-FBR Cobb angle and traditional FBR Cobb angle(t = 2.0, P = 0.051). The maximum height of CH-FBR, basic weight and maximum weight were (29.6 ± 1.4)cm,(20 ± 6)kg, and (40 ± 6) kg. Preoperatively, the mean Cobb angle of the 28 structural curves(main thoracic curves) was 46° ± 11°. Postoperatively, the mean Cobb angle was 12° ± 6°. Preoperatively, the mean Cobb angle of the 18 structural curves(thoracolumbar/lumbar curves) was 49° ± 12°. Postoperatively, the mean Cobb angle was 10° ± 5°. The results were same in 28 structural curves, 18 structural curves as well as 46 curves. Correlation analysis of 46 curves indicated that the maximum height of CH-FBR positively correlated with maximum weight (r = 0.69, r(2) = 0.47, P = 0.001), the height changes of CH-FBR positively correlated with weight changes on CH-FBR (r = 0.62, r(2) = 0.38, P = 0.001). CONCLUSIONS: CH-FBR is a more reliable and effective method than traditional FBR and supine side-bending for curve flexibility evaluation in AIS patients. Moreover, compared to the traditional FBR and side-bending radiograph, the flexibility suggested by the optimized height CH-FBR more closely approximates the postoperative result made by pedicle screws fixation and fusion.

Hemangioma of the Ilium Simulating Bone Metastasis on 18 F-PSMA-1007 PET/CT.

ABSTRACT: A 64-year-old man was referred for 18 F-PSMA-1007 PET/CT scan for initial staging of biopsy-proved prostate adenocarcinoma. 18 F-PSMA-1007 PET/CT showed focal intense 18 F-PSMA-1007 of the prostate adenocarcinoma and a focal intense activity with SUV max of 10.5 in the left ilium. The 18 F-PSMA-1007-avid iliac bone lesion corresponded to a hemangioma, which was initially detected on pelvic MRI 13 months ago and remained stable in size. This case indicates that hemangioma should be included in the differential diagnosis of PSMA-avid iliac bone lesions.

Atypical Bone Involvement in Erdheim-Chester Disease Showing No or Subtle Structure Changes and Increased Activity on FDG PET/CT.

ABSTRACT: Bones are the most common sites involved in Erdheim-Chester disease. On imaging, the bone involvement in Erdheim-Chester disease typically presents as osteosclerotic lesions, and osteolytic lesions are unusual. Bone lesions showing no or subtle structure changes are rarely reported. We describe FDG PET/CT findings in a case of Erdheim-Chester disease with atypical bone involvement. The bone lesions showed no or subtle structure changes without obvious osteosclerosis or osteolysis on radiographs and CT, and increased FDG activity mimicking lymphoma. Familiarity with these atypical imaging findings of bone involvement in Erdheim-Chester disease is helpful for the diagnosis.

The effect of phosphorylation on the conformational dynamics and allostery of the association of death-associated protein kinase with calmodulin.

Protein phosphorylation plays an important role in the signal transduction and is capable of regulation of cell activity. The death-associated protein kinase 1 (DAPK1), as a Ser/Thr kinase, interacts with calmodulin (CaM) to regulate apoptotic and autophagic signaling. Autophosphorylation of DAPK1 at Ser308 located at the autoregulatory domain (ARD) blocks CaM binding and inhibits kinase catalytic activity. However, the mechanism underlying the influence of Ser308 phosphorylation (pS308) on the DAPK1 activity remains unclear. Here, we performed multiple, microsecond length molecular dynamics (MD) simulations, the molecular mechanics generalized Born/surface area (MM-GBSA) binding free energy calculations, principal component analysis, and dynamic cross-correlation analysis to unravel the conformational dynamics and allostery of the DAPK1 - CaM interaction triggered by the pS308 at the ARD. MD simulations showed that pS308 affected the conformational stability of the DAPK1 - CaM complex. Further energetic and structural exploration revealed that pS308 weakened the association of the phosphorylated DAPK1 to CaM, which lowered the susceptibility of DAPK1 to be activated by CaM. This result can provide mechanistic insights into the molecular underpinning through which the DAPK1 kinase activity is modulated by the auto-phosphorylation.Communicated by Ramaswamy H. Sarma.

Whole-blood gene expression profiling in ankylosing spondylitis identifies novel candidate genes that may contribute to the inflammatory and tissue-destructive disease aspects.

We performed a comprehensive gene expression analysis to identify differentially expressed genes (DEGs) between AS (ankylosing spondylitis) and health controls. A total of 1454 DEGs were obtained, including 919 up-regulated genes and 535 down-regulated genes. There were 218 interactions and 224 pairs in the conPPI network. Topological analysis showed that 11 genes had a close relationship with AS. GO (gene ontology) functional enrichment analysis of the two modules showed that the DEGs in conPPI mainly participated in the biologic process of immune response. The KEGG pathway analysis showed that most DEGs in the two modules were enriched into cell receptor signaling pathway, natural killer cell mediated cytotoxicity and primary immunodeficiency. We hypothesized that these DEGs associated with immune response DEGs might provide basic for depth understanding of the AS development.

Cytogenetic analysis in 16-year follow-up study of a mother and fetus exposed in a radiation accident in Xinzhou, China.

In November 1992, a radiation accident occurred in Xinzhou, due to the collection by a farmer of an unused (60)Co source; 37 individuals were exposed to ionizing radiation. Three individuals died and the farmer's 19-weeks-pregnant wife suffered acute radiation symptoms. Conventional chromosome analysis, cytokinesis-block micronuclei (CBMN) assay and fluorescence in situ hybridization (FISH) painting with three pairs of whole chromosome probes were used to analyze chromosomal aberrations for the pregnant female and her baby during the 16 years following the accident. The yields of dicentrics and rings (dic+r) continually declined between 41 days and 16 years after the accident. The frequency of binucleated MN also decreased over time for both mother and daughter. Sixteen years after exposure, the yields of dic+r and binucleated MN decreased to normal levels, but the reciprocal translocation frequencies remained elevated, for both mother and daughter. FISH results showed a decreasing yield of translocations with time. Based on the changes in maternal translocation frequency, the daughter's dose at the time of exposure was estimated as 1.82 (1.35-2.54)Gy. This was consistent with the clinical manifestations of severe mental retardation and low IQ score. FISH-based translocation analysis can be used for follow-up studies on accidental exposure and, after correction, for retrospective dose estimation for individuals prenatally exposed to radiation.

Comparison of the pedicle screws placement between electronic conductivity device and normal pedicle finder in posterior surgery of scoliosis.

STUDY DESIGN: Prospective randomized clinical trial. OBJECTIVE: To compare the accuracy and time using of pedicle screw placement between electronic conductivity device (ECD) and normal pedicle finder (NPF) in posterior surgery of scoliosis, through a randomized clinical trial. SUMMARY OF BACKGROUND DATA: Pedicle screw insertion for scoliosis correction can be associated with increased pedicle perforations. The malposition rates using various techniques in different region of the spine have been reported to occur with a frequency of 3.3%-43%. An ECD has been reported in spine surgeries, but its accuracy and surgical time comparing with NPF in the presence of scoliosis has not been reported. METHODS: The 42 patients of adolescent idiopathic scoliosis with average major Cobb angle of 55.3±7 degrees (range, 45-78 degrees), who received posterior correction surgeries using pedicle screws system only were divided into 2 groups by random: group NPF (22 patients); and group ECD (20 patients). NPF group had 332 screws and ECD group had 362 screws. The 2 groups were compared for accuracy of screw placement, time for screw insertion, and the number of times the C-arm had to be brought into the field. RESULTS: There were 47 (14.2%) pedicle perforation in the NPF group as compared with only 15 (4.1%) in the ECD group (P<0.001). Although in different region of the spine, screw accuracy showed discrepant statistical result, with upper (T1-T3), middle (T4-T7), and lower thoracic (T8-T10) comparison showing significant statistical difference (P=0.010, 0.001, and 0.041, respectively) and thoracolumbar (T11-L2) and lower lumbar (L3-L5) comparison showing no significant statistical difference (P=0.278 and 0.292, respectively). Average screw insertion time in the NPF group was 241±61 seconds compared with 204±33 seconds in the ECD group (P=0.009). The C-arm had to be moved into the operation field on an average of 1.59±0.67 times in the NPF group compared with 1.20±0.52 in the ECD group (P=0.040). CONCLUSIONS: ECD increases pedicle screw accuracy, especially in T1-T10, and reduces insertion time and radiation in posterior adolescent idiopathic scoliosis.