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1.
Eur Spine J ; 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38907855

RESUMO

PURPOSE: Prolonged mechanical ventilation (PMV) and reintubation are among the most serious postoperative adverse events associated with malignant cervical tumors. In this study, we aimed to clarify the incidence, characteristics, and risk factors for PMV and reintubation in target patients. METHODS: This retrospective nested case-control study was performed between January 2014 and January 2020 at a large spinal tumor center in China. Univariate analysis was used to identify the possible risk factors associated with PMV and reintubation. Logistic regression analysis was performed to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) with covariates of a probability < 0.05 in univariate analysis. RESULTS: From a cohort of 560 patients with primary malignant (n = 352) and metastatic (n = 208) cervical tumors, 27 patients required PMV and 20 patients underwent reintubation. The incidence rates of PMV and reintubation were 4.82% and 3.57%, respectively. Three variables (all p < 0.05) were independently associated with an increased risk of PMV: Karnofsky Performance Status < 50 compared to ≥ 80, operation duration ≥ 8 h compared to < 6 h, and C4 nerve root encased by the tumor. Longer operative duration and preoperative hypercapnia (all p < 0.05) were independent risk factors for postoperative reintubation, both of which led to longer length of stay (32.6 ± 30.8 vs. 10.7 ± 5.95 days, p < 0.001), with an in-hospital mortality of 17.0%. CONCLUSION: Our results demonstrate the risk factors for PMV or reintubation after surgery for malignant cervical tumors. Adequate assessment, early detection, and prevention are necessary for this high-risk population.

2.
Heliyon ; 10(8): e29446, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38660275

RESUMO

Background: The diagnostic yield of radial endobronchial ultrasound (r-EBUS) for the diagnosis of peripheral pulmonary lesions (PPLs) varies between studies and is affected by multiple factors. We aimed to evaluate the efficacy and safety of r-EBUS, and to explore the factors influencing the diagnostic yield of r-EBUS in patients with PPLs. Methods: The PubMed, Web of Science, and EMBASE databases were searched to identify relevant studies that used r-EBUS for diagnosing PPLs from the date of inception to Dec 2022. Meta-analysis was conducted using Review Manager 5.4 and Stata 15.1. Results: An analysis of 46 studies with a total of 7252 PPLs was performed. The pooled diagnostic yield of r-EBUS was 73.4 % (95 % CI: 69.9%-76.7 %), with significant heterogeneity detected among studies (I2 = 90 %, P < 0.001). Further analysis demonstrated PPLs located in the middle or lower lobe, >2 cm in size, malignant in type, solid in appearance on computerized tomography (CT), present in bronchus sign, the within probe location, and the addition of rapid on-site evaluation (ROSE) were associated with increased diagnostic yield, whereas use of a guide sheath (GS), bronchoscopy type, and a multimodality approach failed to influence the outcome. The pooled incidence rates of overall complications, pneumothorax and moderate and severe bleeding were 3.1 % (95 % CI: 2.1%-4.3 %), 0.4 % (95 % CI: 0.1%-0.7 %) and 1.1 % (95 % CI: 0.5%-2.0 %), respectively. Conclusions: r-EBUS has an appreciable diagnostic yield and an excellent safety manifestation when used to deal with PPLs.

3.
Spine (Phila Pa 1976) ; 49(10): 715-725, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38239008

RESUMO

STUDY DESIGN: A retrospective case series. OBJECTIVE: This study developed a novel classification system based on imaging and anatomy to select optimal surgical approaches and reconstruction strategies to achieve total resection of cervical dumbbell tumors and restore spinal stability. SUMMARY OF BACKGROUND DATA: Total resection is necessary to decrease the recurrence rate of cervical dumbbell tumors. Previous cervical dumbbell tumor classifications are insufficient for determining surgical strategies; therefore, a practical classification is needed. MATERIALS AND METHODS: This study included 295 consecutive patients with cervical dumbbell tumors who underwent total surgical resection. A novel classification of cervical dumbbell tumors was developed based on magnetic resonance imaging and computed tomography. Continuous variables were expressed as mean±SD and were compared using an unpaired two-tailed Student t test. The χ 2 test or the Fisher exact test was used for categorical variables. Kendall's W test assessed three independent raters' inter-rater and intrarater reliabilities on 140 cervical dumbbell tumors. RESULTS: The inter-rater and intrarater consistency coefficient was 0.969 (χ 2 =404.3, P <0.001) and 0.984 (χ 2 =273.7, P <0.001). All patients with type I and II tumors underwent single-posterior surgeries to achieve total resection. Of the patients in this study, 86.1%, 25.9%, 75.9%, and 76.9% underwent posterior surgeries for types IIIa, IIIb, IVa, and V tumors, respectively. All patients with type IVb tumors underwent a combined anterior and posterior approach. Posterior internal fixation was used for all patients in posterior surgery. Anterior reconstruction was applied for patients with type IVb tumors (20/20, 100%) and some with type V tumors (3/13, 23.1%). The mean follow-up duration was 93.6±2.6 months. A recurrence was observed in 19 (6.4%) patients. CONCLUSION: The authors describe a novel classification system that is of practical use for planning the complete resection of cervical dumbbell tumors.


Assuntos
Vértebras Cervicais , Procedimentos de Cirurgia Plástica , Humanos , Vértebras Cervicais/cirurgia , Vértebras Cervicais/diagnóstico por imagem , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto , Idoso , Procedimentos de Cirurgia Plástica/métodos , Neoplasias da Coluna Vertebral/cirurgia , Neoplasias da Coluna Vertebral/diagnóstico por imagem , Neoplasias da Coluna Vertebral/classificação , Adulto Jovem , Imageamento por Ressonância Magnética/métodos , Reprodutibilidade dos Testes , Adolescente , Tomografia Computadorizada por Raios X
4.
Orthop Surg ; 16(1): 78-85, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38014475

RESUMO

OBJECTIVE: Recurrent giant cell tumor (RGCT) of the spine represents a clinical challenge for surgeons, and the treatment strategy remains controversial. This study aims to describe the long-term follow-up outcomes and compare the efficacy of en bloc spondylectomy versus piecemeal spondylectomy in treating RGCT of the thoracolumbar spine. METHODS: A total of 32 patients with RGCT of the thoracolumbar spine treated from June 2012 to June 2019 were retrospectively reviewed. A total of 15 patients received total en bloc spondylectomy (TES) with wide or marginal margin while 17 patients received total piecemeal spondylectomy (TPS) with intralesional margin. Postoperative Eastern Cooperative Oncology Group Performance Score (ECOG-PS), Frankel classification and recurrence-free survival (RFS) were evaluated after surgery. Survival curves were estimated by the Kaplan-Meier method and differences were analyzed with the log-rank test. Multivariate analysis was performed with Cox regression to identify the independent prognostic factors affecting RFS. RESULTS: During a median follow-up of 41.9 ± 17.5 months, all patients with compromised neurologic functions exhibit significant improvement, with the mean ECOG-PS decreasing from 1.5 ± 1.3 to 0.13 ± 0.3 (p < 0.05). Among the 17 patients treated with TPS, eight patients developed local recurrence after a median time of 15.9 ± 6.4 months and four patients died from progressive disease. On the other hand, local recurrence were well managed with TES, since only one out of 15 patients experienced local relapse and all patients are alive with satisfied function at the latest follow-up. The median RFS for patients receiving TES and TPS are 75.0 months (95% CI: 67.5-82.5 m) and 38.3 months (95% CI: 27.3-49.3 m) respectively (p = 0.008). Multivariate analysis shows that the Ki67 index (p = 0.016), resection mode (p = 0.022), and denosumab (p = 0.039) are independent risk factors affecting RFS. CONCLUSIONS: TES with wide/marginal margin should be offered to patients with RGCT whenever feasible, given its long-term benefits in local control and symptom alleviation. Additionally, patients with lower Ki67 index and application of denosumab tend to have a better prognosis.


Assuntos
Tumores de Células Gigantes , Neoplasias da Coluna Vertebral , Humanos , Denosumab/uso terapêutico , Estudos Retrospectivos , Antígeno Ki-67 , Recidiva Local de Neoplasia/tratamento farmacológico , Coluna Vertebral/patologia , Resultado do Tratamento
5.
In Vitro Cell Dev Biol Anim ; 59(6): 420-430, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37460875

RESUMO

Brevilin A (BA) is the primary component of Centipeda minima, which is widely used in Chinese traditional medicine. The anti-inflammatory and anti-tumor properties of BA have been established; however, its function in bone metabolism is not well understood. This study revealed that concentrations of BA below 1.0 µM did not inhibit the proliferation of bone marrow macrophages but did impede the differentiation and bone resorption activity of osteoclasts. Furthermore, BA suppressed the expression of osteoclast-specific genes Mmp9, Acp5, Dc-stamp, Ctsk, and Atp6v0d2. In addition, mTOR, ERK, and NFATc1 activation in bone marrow macrophages were suppressed by BA. As a whole, BA blocks the mTOR and ERK signaling pathways, which is responsible for the development and activity of osteoclasts, and the resorption of bone.


Assuntos
Reabsorção Óssea , Osteoclastos , Animais , Osteoclastos/metabolismo , Reabsorção Óssea/genética , Reabsorção Óssea/patologia , Serina-Treonina Quinases TOR/metabolismo , Ligante RANK/farmacologia , Ligante RANK/metabolismo , Fatores de Transcrição NFATC/genética , Fatores de Transcrição NFATC/metabolismo , Diferenciação Celular/genética , Osteogênese/genética
6.
Sci Rep ; 13(1): 7843, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37188728

RESUMO

This study investigated the influence of stress levels on the mechanical behavior and particle crushing of irregular granular materials. Granular materials with irregular sides were modelled using the discrete element method. A new method of using a shear fracture zone to characterize the deformation of irregular granular materials under high pressure was proposed. The crushing energy is analysed based on the first law of thermodynamics. The shear strength of irregular granular materials shows significantly nonlinear behavior due to particle crushing. The deformation behavior can be characterized with the help of particle rotation under low confining pressure, and can be characterized with the help of particle breakage under high confining pressure. Granular materials easily break into many single fine particles under high confining pressure. The breakage degree can be represented by the value of crushing energy. Irregular granular materials have a large breakage degree under high confining pressures. It weakens the stability of engineered structures constructed from granular materials.

7.
J Clin Neurosci ; 106: 145-151, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36330956

RESUMO

PURPOSE: This study aimed to characterize giant cell tumor of the tendon sheath (GCTTS) in spine more fully and further validate the therapeutical effect of surgcial resection for treating this neoplasm. METHODS: Patients diagnosed with spinal GCTTS and received surgical resection in our hospital between January 2009 and September 2021 were identified retrospectively. The clinical data and radiological images were summarized and the clinical outcomes of patients with a follow-up period of more than 12 months were analyzed. RESULTS: Thirty patients with benign GCTTS and one with malignant GCTTS were included. Preoperative radiological images were available in 28 of 30 benign cases. Benign lesions were revealed as soft tissue masses centering on the facet joint with osteolytic bone destruction in 26 patients on CT, and as prevertebral or intramuscular masses without bone erosion in 2. MRI showed the signal of isointensity or hypointensity on T1 weighted images (T1WI) in 25 patients and slightly hyperintense in three. On T2 weighted images (T2WI), 17 lesions displayed homogeneous hypointense signal, and eight lesions possessed heterogeneous signals. The remaining three lesions featured slightly hyperintense signal on T2WI. Follow-up data were available in 23 of 30 benign cases treated with gross-total resection, and two patients experienced recurrence. CONCLUSIONS: Spinal GCTTS should be suspected in cases with features such as the mass mainly involving the posterior bone elements, the lack of intralesional calcification, T2-weighted dark signals, and free of any cancer. Gross-total resection is an effective means for treating spinal GCTTS.


Assuntos
Tumor de Células Gigantes de Bainha Tendinosa , Tumores de Células Gigantes , Humanos , Estudos Retrospectivos , Seguimentos , Tumor de Células Gigantes de Bainha Tendinosa/patologia , Imageamento por Ressonância Magnética/métodos , Tendões/diagnóstico por imagem , Tendões/cirurgia , Tendões/patologia , Resultado do Tratamento , Tumores de Células Gigantes/diagnóstico por imagem , Tumores de Células Gigantes/epidemiologia , Tumores de Células Gigantes/cirurgia
8.
ACS Synth Biol ; 11(12): 4123-4133, 2022 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-36442151

RESUMO

Pyrimidine ribonucleotide de novo biosynthesis pathway (PRdnBP) is an important pathway to produce pyrimidine nucleosides. We attempted to systematically investigate PRdnBP in Escherichia coli with genome-scale metabolic models and utilized the models to guide strain design. The balance of central carbon metabolism and PRdnBP affected the production of cytidine from glucose. Using Bayesian metabolic flux analysis, the effect of modified PRdnBP on the metabolic network was analyzed. The acetate overflow became coupled with PRdnBP flux, while they were originally independent under oxygen-sufficient conditions. The coupling between cytidine production and acetate secretion in the modified strain was weakened by arcA deletion, which resulted in further improving the efficient accumulation of cytidine. In total, 1.28 g/L of cytidine with a yield of 0.26 g/g glucose was produced. The yield of cytidine produced by E. coli is higher than previous reports. Our strategy provides an effective attempt to find metabolic bottlenecks in genetically engineered bacteria by using flux coupling analysis.


Assuntos
Citidina , Escherichia coli , Escherichia coli/genética , Escherichia coli/metabolismo , Citidina/genética , Citidina/metabolismo , Teorema de Bayes , Glucose/metabolismo , Acetatos/metabolismo , Computadores , Engenharia Metabólica/métodos
9.
Materials (Basel) ; 11(11)2018 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-30441828

RESUMO

The initiation and evolution of the localized corrosion in carbon steel were investigated in a simulated marine environment of Xisha Island in the South China Sea. In the initial stage, localized corrosion occurred in the form of corrosion spot. The localized corrosion morphology and electrochemical information during corrosion process were tracked by field emission scanning electron microscopy energy dispersive spectrometry (FE-SEM-EDS), scanning vibrating electrode technique (SVET) and scanning Kelvin probe force microscopy (SKPFM). Localized corrosion was induced by the microcrevices around Al2O3 inclusions. The occluded cells and oxygen concentration cell formed in the pits could accelerate the localized corrosion. Pearlite accelerated the dissolution of the inside and surrounding ferrite via the galvanic effect between Fe3C and ferrite. Overall, the localized corrosion was initiated and evaluated under a synergistic effect of crevice corrosion, occluded cells, oxygen concentration cell and the galvanic couple between FeC3 and ferrite.

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