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Study design:Retrospective study.Objectives:The purpose of this study was to identify the clinical factors for differentiating malignant from benign intramedullary spinal cord tumors.Setting:Niigata, Japan.Methods:We conducted a retrospective review of charts and images. Preoperative paralysis including walking ability, urinary function, magnetic resonance imaging (MRI) findings and pathological diagnosis were evaluated in 33 consecutive cases of intramedullary spinal cord tumor, and the clinical factors that were useful for differentiating malignant from benign tumors were identified.Results:Early progression of paralysis was the most valuable feature for differentiating malignant from benign tumors. Malignant tumors were suspected in only three of ten cases on the basis of MRI findings.Conclusion:Simple assessment of walking ability is easy to perform and is useful for predicting the pathological malignancy of intramedullary tumors of the spinal cord. [ABSTRACT FROM AUTHOR]

Phosphorus is a key plant nutrient linked to plant growth during the early stages of primary succession in volcanic soils. Available phosphorus is thought to include soil and atmospheric phosphorus, but it is not well understood. Here, we focused on deposition as a potential phosphorus source. We evaluated the contribution of deposition to phosphorus uptake and growth in Fallopia japonica, a key pioneer species of primary succession. When we experimented with growing F. japonica under field conditions, F. japonica not covered by a roof absorbed more phosphorus than that covered by the roof, suggesting the influence of total (dry + wet) deposition. Furthermore, we tested the effects of deposition by treating F. japonica seedlings with wet deposition or distilled water in six volcanic soils. Plants that received the wet deposition treatment exhibited higher phosphorus contents and growth rates than those treated with distilled water. The phosphorus from wet deposition and the phosphorus from soil contributed nearly equally to F. japonica development. Our findings suggest that F. japonica grows during primary succession and builds up the phosphorus cycle by absorbing a trace amount of phosphorus from deposition and volcanic soils., (© 2023. Springer Nature Limited.)

Background: Surgical smoke is a vaporous by-product generated during tissue incision and cauterization with an electric scalpel. This smoke contains tissue- and blood/vascular-derived substances, bacteria, viruses, and chemical substances. Among them, it contains many fine particles called particulate matter (PM) 2.5, which are harmful and hazardous to the human body. We aimed to investigate the occurrence of PM2.5 in surgical smoke produced during spinal surgery and to evaluate the efficacy of an electric scalpel with a smoke evacuation pencil., Methods: In this retrospective observational study, 89 patients who underwent spinal surgery between June 2019 and May 2021 were included. A dust monitor was installed in the operating room to measure the PM2.5 air concentration during the surgery. During each surgery, the total amount of PM2.5, the maximum PM2.5 air concentration, the exposure time to PM2.5, and the average value of PM2.5 air concentration from the start to the end of the surgery were calculated., Results: We found that in 29 of the 89 cases (32.6%), the air concentration of PM2.5 increased to a level that could cause health damage during the surgery. Twelve cases (13.4%) reached the level that could cause serious health damage, and 8 cases (9%) reached an emergency warning level. The total amount and the maximum and average levels of PM2.5 were significantly suppressed in the surgery with a smoke evacuation pencil group than in the surgery without a smoke evacuation pencil group., Conclusion: We detected hazardous levels of PM2.5 in the air during spinal surgery, highlighting the importance of considering smoke control or reduction during spinal surgery. We recommend using an electric scalpel with a smoke evacuation pencil for regulating PM2.5 levels in the operating room., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest., (Copyright © 2022 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.)

The geneLEAD VIII is a fully-automated nucleic acid extraction/quantitative PCR equipment developed by Precision System Science Co., Ltd., (PSS). To take advantage of its capability, we developed a quantitative assay system to measure growth of animal viruses. The system was used to assay one of the Chinese herbal extracts whose anti-malarial activities were previously reported and demonstrated its dose-dependent anti-viral activity against feline infectious peritonitis virus (FIPV), a feline coronavirus causing the fatal diseases in cats, and relatively low cell toxicity. The assay developed in this study is useful to screen antiviral drugs and the anti-FIPV activity of the herbal extract identified have a potential to lead to development of new drugs against FIPV and other coronaviruses, such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

Background: This study aimed to report an aortic pseudoaneurysm, a rare but lethal complication, after a spinal fracture in ankylosing spine., Observations: An 83-year-old obese woman presented with dementia and was nonambulatory after a fall. She was transported to the hospital, and imaging showed a hyperextension-type L1 fracture with diffuse idiopathic skeletal hyperostosis (DISH). After posterior fusion surgery using percutaneous pedicle screws, screw loosening was detected 10 days postoperatively. Fracture dislocation was reduced by changing to transdiscal screws and rodding while in the lateral position. However, the anterior opening persisted. Enhanced computed tomography performed at 6 weeks postoperatively showed a large aortic pseudoaneurysm extending into the vertebral fracture site without screw loosening. Neither endovascular aortic repair nor open surgery was applicable. The patient was transferred to a sanatorium and died of pneumonia 5 months postoperatively without aortic aneurysm rupture., Lessons: An aortic pseudoaneurysm can occur in hyperextension-type spinal fractures in DISH, even after fusion surgery, when the edge of the fracture is in contact with the aortic wall. The anterior opening dislocation should be reduced as much as possible.

Teriparatide (TPTD) administration has a potent osteogenic action and promotes the healing of osteoporotic vertebral fractures (OVFs). We aimed to investigate the outcomes of vertebroplasty with posterior spinal fusion (VP + PSF) and determine the impact of perioperative TPTD administration. We included 73 patients (18 male and 55 female patients; mean age: 78 years) with thoracolumbar OVFs who underwent VP + PSF and were followed-up for at least 2 years. Twenty-three patients who received TPTD perioperatively for > 3 months were included in the TPTD group, and the remaining 50 patients were included in the non-TPTD group. Radiographic findings regarding sagittal alignment and clinical outcomes in both groups were compared. The mean duration of TPTD administration was 17.5 ± 5.0 months (range 4-24 months). The mean loss of correction of local kyphosis angle in the TPTD group (4.0°) was lesser than that in the non-TPTD group (7.5°; p < 0.05); however, no significant differences were observed between the groups regarding global sagittal alignment, the occurrence of subsequent vertebral fractures, pedicle screw loosening and treatment-efficacy rates of clinical outcomes. Local kyphosis correction in patients who underwent VP + PSF for OVFs could be maintained through perioperative TPTD administration; however, TPTD administration had little effect on clinical outcomes., (© 2022. The Author(s).)

Importance: The optimal management for acute traumatic cervical spinal cord injury (SCI) is unknown., Objective: To determine whether early surgical decompression results in better motor recovery than delayed surgical treatment in patients with acute traumatic incomplete cervical SCI associated with preexisting canal stenosis but without bone injury., Design, Setting, and Participants: This multicenter randomized clinical trial was conducted in 43 tertiary referral centers in Japan from December 2011 through November 2019. Patients aged 20 to 79 years with motor-incomplete cervical SCI with preexisting canal stenosis (American Spinal Injury Association [ASIA] Impairment Scale C; without fracture or dislocation) were included. Data were analyzed from September to November 2020., Interventions: Patients were randomized to undergo surgical treatment within 24 hours after admission or delayed surgical treatment after at least 2 weeks of conservative treatment., Main Outcomes and Measures: The primary end points were improvement in the mean ASIA motor score, total score of the spinal cord independence measure, and the proportion of patients able to walk independently at 1 year after injury., Results: Among 72 randomized patients, 70 patients (mean [SD] age, 65.1 [9.4] years; age range, 41-79 years; 5 [7%] women and 65 [93%] men) were included in the full analysis population (37 patients assigned to early surgical treatment and 33 patients assigned to delayed surgical treatment). Of these, 56 patients (80%) had data available for at least 1 primary outcome at 1 year. There was no significant difference among primary end points for the early surgical treatment group compared with the delayed surgical treatment group (mean [SD] change in ASIA motor score, 53.7 [14.7] vs 48.5 [19.1]; difference, 5.2; 95% CI, -4.2 to 14.5; P = .27; mean [SD] SCIM total score, 77.9 [22.7] vs 71.3 [27.3]; P = .34; able to walk independently, 21 of 30 patients [70.0%] vs 16 of 26 patients [61.5%]; P = .51). A mixed-design analysis of variance revealed a significant difference in the mean change in ASIA motor scores between the groups (F1,49 = 4.80; P = .03). The early surgical treatment group, compared with the delayed surgical treatment group, had greater motor scores than the delayed surgical treatment group at 2 weeks (mean [SD] score, 34.2 [18.8] vs 18.9 [20.9]), 3 months (mean [SD] score, 49.1 [15.1] vs 37.2 [20.9]), and 6 months (mean [SD] score, 51.5 [13.9] vs 41.3 [23.4]) after injury. Adverse events were common in both groups (eg, worsening of paralysis, 6 patients vs 6 patients; death, 3 patients vs 3 patients)., Conclusions and Relevance: These findings suggest that among patients with cervical SCI, early surgical treatment produced similar motor regain at 1 year after injury as delayed surgical treatment but showed accelerated recovery within the first 6 months. These exploratory results suggest that early surgical treatment leads to faster neurological recovery, which requires further validation., Trial Registration: ClinicalTrials.gov Identifier: NCT01485458; umin.ac.jp/ctr Identifier: UMIN000006780.

Background: This study aimed to determine the indications for drainage in extended haematogenous iliopsoas abscesses (IPAs), which include both primary and vertebral osteomyelitis-related IPAs., Methods: Sixty-three IPA patients who were initially treated with only antibiotics and no drainage were enrolled. The success (S) group included patients who were cured without drainage, while the failure (F) group included those who required open or percutaneous drainage or died., Results: Compared with patients in the S group, patients in the F group (n = 15) had a higher incidence of end-stage renal disease on hemodialysis, compromised immunity, vertebral osteomyelitis of the cervicothoracic spine, other musculoskeletal infections, and multilocular abscesses. The IPAs in the F group had larger transverse and longitudinal diameters. In receiver operating characteristic curve analyses for the diameter of IPAs, the most valuable cut-off points predicting the F group were a longitudinal diameter of 5.0 cm (sensitivity, 1.0; specificity, 0.67) and a transverse diameter of 2.3 cm (sensitivity, 0.73; specificity, 0.73). A combination of both diameter cut-offs had high specificity (sensitivity, 0.73; specificity, 0.90)., Conclusions: Drainage should be applied in case of a larger abscess with transverse diameter ≥ 2.3 cm and longitudinal diameter ≥ 5.0 cm. Conversely, IPAs with longitudinal diameter <5 cm do not require drainage. Haemodialysis, compromised immunity, vertebral osteomyelitis of the cervicothoracic spine, and musculoskeletal infections are risk factors of conservative treatment failure., Competing Interests: Declaration of competing interest The authors declare that they have no conflicts of interest., (Copyright © 2020 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.)

Purpose: To elucidate clinico-radiological features, therapeutic outcomes, and survival factors of vertebral osteomyelitis patients infected by methicillin-resistant staphylococci (MRS)., Methods: Vertebral osteomyelitis patients admitted to the orthopaedic department between 2007 and 2011 (n = 248) were selected for this multicenter study. We compared patients' backgrounds, therapeutic course, and in-hospital mortality between MRS and methicillin-susceptible staphylococci (MSS). We also examined survival factors of vertebral osteomyelitis due to MRS., Results: Sixteen patients of MRS vertebral osteomyelitis and 55 patients of MSS were included in this study. In MRS vertebral osteomyelitis, the rates of comorbid diabetes mellitus, involvement of >2 vertebral bodies, in-hospital mortality, and operation of surgical debridement were higher compared to those in MSS vertebral osteomyelitis. Univariate analysis showed that operation of surgical debridement was a factor related to survival in MRS patients., Conclusions: Higher rate of comorbid diabetes mellitus, involvement of >2 vertebral bodies, in-hospital mortality, and performing surgical debridement are peculiar features of MRS vertebral osteomyelitis compared to MSS vertebral osteomyelitis. If patients with MRS vertebral osteomyelitis respond poorly to antibiotic therapy, it might be better to consider surgical debridement not to lose an opportunity of operation due to exacerbation of systemic conditions., (Copyright © 2016 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.)

The cell surface receptor, low-density lipoprotein receptor-related protein 5 (LRP5) is a key regulator of bone mass. Loss-of-function mutations in LRP5 cause the human skeletal disease osteoporosis-pseudoglioma syndrome, an autosomal recessive disorder characterized by severely reduced bone mass and strength. We investigated the role of LRP5 on bone strength using mice engineered with a loss-of-function mutation in the gene. We then tested whether the osteogenic response to mechanical loading was affected by the loss of Lrp5 signaling. Lrp5-null (Lrp5-/-) mice exhibited significantly lower bone mineral density and decreased strength. The osteogenic response to mechanical loading of the ulna was reduced by 88 to 99% in Lrp5-/- mice, yet osteoblast recruitment and/or activation at mechanically strained surfaces was normal. Subsequent experiments demonstrated an inability of Lrp5-/- osteoblasts to synthesize the bone matrix protein osteopontin after a mechanical stimulus. We then tested whether Lrp5-/- mice increased bone formation in response to intermittent parathyroid hormone (PTH), a known anabolic treatment. A 4-week course of intermittent PTH (40 microg/kg/day; 5 days/week) enhanced skeletal mass equally in Lrp5-/- and Lrp5+/+ mice, suggesting that the anabolic effects of PTH do not require Lrp5 signaling. We conclude that Lrp5 is critical for mechanotransduction in osteoblasts. Lrp5 is a mediator of mature osteoblast function following loading. Our data suggest an important component of the skeletal fragility phenotype in individuals affected with osteoporosis-pseudoglioma is inadequate processing of signals derived from mechanical stimulation and that PTH might be an effective treatment for improving bone mass in these patients.