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1.
BMC Musculoskelet Disord ; 21(1): 734, 2020 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-33172435

RESUMEN

BACKGROUND: The aim of this study is to introduce a new method of percutaneous endoscopic decompression under 3D real-time image-guided navigation for spinal stenosis in degenerative kyphoscoliosis patients without instability or those who with multiple comorbidities. Decompression alone using endoscope for kyphoscoliosis patient is technical demanding and may result in unnecessary bone destruction leading to further instability. The O-arm/StealthStation system is popular for its ability to provide automated registration with intraoperative, postpositioning computed tomography (CT) which results in superior accuracy in spine surgery. METHODS: In this study, we presented four cases. All patients were over seventy years old female with variable degrees of kyphoscoliosis and multiple comorbidities who could not endure major spine fusion surgery. Percutaneous endoscopic unilateral laminotomy and bilateral decompression under 3D real-time image-guided navigation were successfully performed. Patients' demographics, image study parameters, and outcome measurements including pre- and post-operative serial Visual analog scale (VAS), and Oswestry Disability Index (ODI) were well documented. The follow-up time was 1 year. RESULTS: Pre- and post-operative MRI showed average dural sac cross sectional area (DSCSA) improved from 81.62 (range 67.34-89.07) to 153.27 (range 127.96-189.73). Preoperative neurological symptoms including radicular leg pain improved postoperatively. The mean ODI (%) were 85 (range 82.5-90) at initial visit, 35.875 (range 25-51) at 1 month post-operatively, 26.875 (range 22.5-35) at 6 months post-operatively and 22.5 (range 17.5-30) at 12 months post-operatively (p < 0.05). The mean VAS score were 9 (range 8-10) at initial visit, 2.25 (range 2-3) at 1 month post-operatively, 1.75 (range 1-2) at 6 months post-operatively and 0.25 (range 0-1) at 12 months post-operatively (p < 0.05). There was no surgery-related complication. CONCLUSIONS: To the best of our knowledge, this is the first preliminary study of percutaneous endoscopic laminotomy under O-arm navigation with successful outcomes. The innovative technique may serve as a promising solution in treating spinal stenosis patients with lumbar kyphoscoliosis and multiple comorbidities.


Asunto(s)
Estenosis Espinal , Cirugía Asistida por Computador , Anciano , Descompresión Quirúrgica , Femenino , Humanos , Imagenología Tridimensional , Laminectomía , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Estenosis Espinal/complicaciones , Estenosis Espinal/diagnóstico por imagen , Estenosis Espinal/cirugía , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
2.
Bioengineering (Basel) ; 11(6)2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38927791

RESUMEN

The internal mechanisms of dental air turbine handpieces (DATHs) have become increasingly intricate over time. To enhance the operational reliability of dental procedures and guarantee patient safety, this study formulated temporal convolution network (TCN) prediction models with the functions of causality in time sequence, transmitting memory, learning, storing, and fast convergence for monitoring the health and diagnosing the rotor and collet failure of DATHs. A handpiece mimicking a dentist's hand load of 100 g was employed to repeatedly mill a glass porcelain block back and forth for cutting. An accelerometer was employed to capture vibration signals during free-running of unrestrained operation of the handpiece, aiming to discern the characteristic features of these vibrations. These data were then utilized to create a diagnostic health classification (DHC) for further developing a TCN, a 1D convolutional neural network (CNN), and long short-term memory (LSTM) prediction models. The three frameworks were used and compared for machine learning to establish DHC prediction models for the DATH. The experimental results indicate that, in terms of DHC predicted for the experimental dataset, the square categorical cross-entropy loss function error of the TCN framework was generally lower than that of the 1D CNN, which did not have a memory framework or the drawback of the vanishing gradient problem. In addition, the TCN framework outperformed the LSTM model, which required a longer history to provide sufficient diagnostic ability. Still, high accuracies were achieved both in the direction of feed-drive milling and in the gravity of the handpiece through vibration signals. In general, the failure classification prediction model could accurately predict the health and failure mode of the dental handpiece before the use of the DATH when an embedded sensor was available. Therefore, this model could prove to be a beneficial tool for predicting the deterioration patterns of real dental handpieces in their remaining useful life.

3.
Biomed Res Int ; 2019: 7196528, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31828123

RESUMEN

BACKGROUND: The pedicle screw is one of the main tools used in spinal deformity correction surgery. Robotic and navigated surgeries are usually used, and they provide superior accuracy in pedicle screw placement than free-hand and fluoroscopy-guided techniques. However, their high cost and space limitation are problematic. We provide a new solution using 3D printing technology to facilitate spinal deformity surgery. METHODS: A workflow was developed to assist spinal deformity surgery using 3D printing technology. The trajectory and profile of pedicle screws were determined on the image system by the surgical team. The engineering team designed drill templates based on the bony surface anatomy and the trajectory of pedicle screws. Their effectiveness and safety were evaluated during a preoperative simulation surgery. The surgery consisted in making a pilot hole through the drill template on a computed tomography- (CT-) based, full-scale 3D spine model for every planned segment. Somatosensory evoke potential (SSEP) and motor evoke potential (MEP) were used for intraoperative neurophysiological monitoring. Postoperative CT was obtained 6 months after the correction surgery to confirm the screw accuracy. RESULTS: From July 2015 to November 2016, we performed 10 spinal deformity surgeries with 3D printing technology assistance. In total, 173 pedicle screws were implanted using drill templates. No notable change in SSEP and MEP or neurologic deficit was noted. Based on postoperative CT scans, the acceptable rate was 97.1% (168/173). We recorded twelve pedicle screws with medial breach, six with lateral breach, and five with inferior breach. Medial breach (12/23) was the main type of penetration. Lateral breach occurred mostly in the concave side (5/6). Most penetrations occurred above the T8 level (69.6%, 16/23). CONCLUSION: 3D printing technology provides an effective alternative for spinal deformity surgery when expensive medical equipment, such as intraoperative navigation and robotic systems, is unavailable.


Asunto(s)
Procedimientos Neuroquirúrgicos/instrumentación , Tornillos Pediculares , Impresión Tridimensional , Enfermedades de la Médula Espinal/cirugía , Adolescente , Adulto , Niño , Femenino , Humanos , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/fisiopatología , Vértebras Lumbares/cirugía , Masculino , Persona de Mediana Edad , Robótica/instrumentación , Enfermedades de la Médula Espinal/diagnóstico por imagen , Enfermedades de la Médula Espinal/fisiopatología , Fusión Vertebral/instrumentación , Cirugía Asistida por Computador/instrumentación , Tomografía Computarizada por Rayos X , Adulto Joven
4.
Int J Clin Exp Med ; 8(11): 20712-21, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26884994

RESUMEN

Liver function is not considered as a risk factor by current risk scores, such as EUROSCORE II or STS-Score for cardiac surgery. The aim of this study was to review the role of liver dysfunction, classified by the Child-Turcotte-Pugh classification or model for end-stage liver disease scores, as a risk factor for mortality and morbidity of patients following cardiac surgery. The Pubmed referencing library was searched. The rates of mortality and morbidity were calculated using SPSS software. The mortality rates in patients of Child class A, Child class B, and Child class C were pairwise compared respectively. A total of 22 reports including 939 patients from eight countries were reviewed. The mortality rate of patients increased in accordance with increased CTP classification. The lowest mortality rate was recorded in Child class A patients, followed by Child class B patients and the highest mortality rate was observed in Child class C patients. The mean complication rate ranged from 3.82% to 22.15%. Child class C patients should be considered unacceptable for cardiovascular surgery. As two studies revealed, patients with a higher MELD score had significantly higher mortality rates. Liver function should be viewed as an important risk factor for cardiovascular surgery, based on its strong association with mortality and morbidity.

5.
Oncotarget ; 5(21): 10718-31, 2014 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-25301739

RESUMEN

Chondrosarcoma is the second most common primary malignant bone cancer, with potential for local invasion and distant metastasis. Chemokine CCL5 (formerly RANTES) of the CC-chemokine family plays a crucial role in metastasis. Angiogenesis is essential for the cancer metastasis. However, correlation of CCL5 with vascular endothelial growth factor (VEGF) expression and angiogenesis in human chondrosarcoma is still unknown. CCL5-mediated VEGF expression was assessed by qPCR, ELISA, and Western blotting. CCL5-induced angiogenesis was examined by migration and tube formation in endothelial progenitor cells in vitro. CCL5 increased VEGF expression and also promoted chondrosarcoma conditional medium-mediated angiogenesis in vitro and in vivo. Stimulation of chondrosarcoma with CCL5 augmented PI3K and Akt phosphorylation, while PI3K and Akt inhibitor or siRNA abolished CCL5-induced VEGF expression and angiogenesis. We also demonstrated CCL5 inhibiting miR-200b expression and miR-200b mimic reversing the CCL5-enhanced VEGF expression and angiogenesis. Moreover, in chondrosarcoma patients showed the positive correlation between CCL5 and VEGF; negative correlation between CCL5 and miR-200b. Taken together, results demonstrate CCL5 promoting VEGF-dependent angiogenesis in human chondrosarcoma cells by down-regulating miR-200b through PI3K/Akt signaling pathway.


Asunto(s)
Neoplasias Óseas/irrigación sanguínea , Quimiocina CCL5/metabolismo , Condrosarcoma/irrigación sanguínea , MicroARNs/genética , Neovascularización Patológica , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Animales , Apoptosis , Western Blotting , Neoplasias Óseas/metabolismo , Neoplasias Óseas/patología , Movimiento Celular , Proliferación Celular , Células Cultivadas , Quimiocina CCL5/genética , Embrión de Pollo , Condrosarcoma/metabolismo , Condrosarcoma/patología , Membrana Corioalantoides , Regulación hacia Abajo , Células Progenitoras Endoteliales/metabolismo , Ensayo de Inmunoadsorción Enzimática , Humanos , Masculino , Ratones , Ratones Desnudos , Fosfatidilinositol 3-Quinasas/genética , Fosforilación , Proteínas Proto-Oncogénicas c-akt/genética , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal , Factor A de Crecimiento Endotelial Vascular/genética , Ensayos Antitumor por Modelo de Xenoinjerto
6.
Dalton Trans ; 42(48): 16857-67, 2013 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-24085317

RESUMEN

The synthesis of two homochiral l-tartrate-copper(II) coordination polymers, [Cu2(C4H4O6)2(H2O)2·xH2O]n (1), and [Cu(C4H4O6)]n (2), under hydrothermal conditions, is reported. Compound 1 adopts a 2D layered network structure with a space group of P21, while compound 2 features a 3D network structure with a space group P21212. Interestingly, the 2D layered structure of compound 1 can undergo a crystal-to-crystal network reassembly, with the formation of the 3D network structure of compound 2 under dehydration conditions. Variable temperature and field magnetic studies reveal the existence of a distinct ferromagnetic interaction between Cu(2+) ions as the result of distinct syn-anti carboxylate bridging coordination modes.


Asunto(s)
Complejos de Coordinación/química , Cobre/química , Imanes/química , Tartratos/química , Desecación , Modelos Moleculares , Temperatura , Agua/química
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