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PURPOSE: This study aimed to establish a nomogram to predict the risk of venous thromboembolism (VTE), identifying potential risk factors, and providing theoretical basis for prevention of VTE after spinal surgery. METHODS: A retrospective analysis was conducted on 2754 patients who underwent spinal surgery. The general characteristics of the training group were initially screened using univariate logistic analysis, and the LASSO method was used for optimal prediction. Subsequently, multivariate logistic regression analysis was performed to identify independent risk factors for postoperative VTE in the training group, and a nomogram for predict risk of VTE was established. The discrimination, calibration, and clinical usefulness of the nomogram were separately evaluated using the C-index, receiver operating characteristic curve, calibration plot and clinical decision curve, and was validated using data from the validation group finally. RESULTS: Multivariate logistic regression analysis identified 10 independent risk factors for VTE after spinal surgery. A nomogram was established based on these independent risk factors. The C-index for the training and validation groups indicating high accuracy and stability of the model. The area under the receiver operating characteristic curve indicating excellent discrimination ability; the calibration curves showed outstanding calibration for both the training and validation groups. Decision curve analysis showed the clinical net benefit of using the nomogram could be maximized in the probability threshold range of 0.01-1. CONCLUSION: Patients undergoing spinal surgery with elevated D-dimer levels, prolonger surgical, and cervical surgery have higher risk of VTE. The nomogram can provide a theoretical basis for clinicians to prevent VTE.
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Nomogramas , Tromboembolia Venosa , Humanos , Estudios Retrospectivos , Tromboembolia Venosa/epidemiología , Tromboembolia Venosa/etiología , Tromboembolia Venosa/prevención & control , Procedimientos Neuroquirúrgicos , Cuello , Factores de RiesgoRESUMEN
The sluggish kinetics of the oxygen evolution reaction (OER) always results in a high overpotential at the anode of water electrolysis and an excessive electric energy consumption, which has been a major obstacle for hydrogen production through water electrolysis. In this study, we present a CoNi-LDH/Fe MOF/NF heterostructure catalyst with nanoneedle array morphology for the OER. In 1.0 M KOH solution, the heterostructure catalyst only required overpotentials of 275 and 305 mV to achieve high current densities of 500 and 1000 mA/cm2 for OER, respectively. The catalytic activities are much higher than those of the reference single-component CoNi-LDH/NF and Fe MOF/NF catalysts. The improved catalytic performance of the heterostructure catalyst can be ascribed to the synergistic effect of CoNi-LDH and Fe MOF. In particular, when the anodic OER is replaced with the urea oxidation reaction (UOR), which has a relatively lower thermodynamic equilibrium potential and is expected to reduce the cell voltage, the overpotentials required to achieve the same current densities can be reduced by 80 and 40 mV, respectively. The cell voltage required to drive overall urea splitting (OUS) is only 1.55 V at 100 mA/cm2 in the Pt/C/NF||CoNi-LDH/Fe MOF/NF two-electrode electrolytic cell. This value is 60 mV lower compared with that required for overall water splitting (OWS). Our results indicate that a reasonable construction of a heterostructure catalyst can significantly give rise to higher electrocatalytic performance, and using UOR to replace the anodic OER of the OWS can greatly reduce the electrolytic energy consumption.
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MicroRNAs are a class of small endogenous non-coding RNAs that function as post-transcriptional regulators. In our previous study, we found that miR-181b was significantly downregulated in human gastric adenocarcinoma tissue samples compared to the adjacent normal gastric tissues. In this study, we confirm the down-regulation of miR-181b in human gastric cancer cell lines versus the gastric epithelial cells. Overexpression of miR-181b suppressed the proliferation and colony formation rate of gastric cancer cells. miR-181b downregulated the expression of cAMP responsive element binding protein 1 (CREB1) by binding its 3' untranslated region. Overexpression of CREB1 counteracted the suppression of growth in gastric cancer cells caused by ectopic expression of miR-181b. These results indicate that miR-181b may function as a tumor suppressor in gastric adenocarcinoma cells through negative regulation of CREB1.
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Adenocarcinoma/metabolismo , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/biosíntesis , Regulación Neoplásica de la Expresión Génica , MicroARNs/metabolismo , Neoplasias Gástricas/metabolismo , Regiones no Traducidas 3' , Proliferación Celular , Perfilación de la Expresión Génica , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Oligonucleótidos Antisentido/genéticaRESUMEN
OBJECTIVE: To evaluate the placement feasibility and safety of the newly designed retropharyngeal reduction plate by cadaveric test and to perform morphometric trajectory analysis. METHODS: The five cadaveric specimens with intact atlantoaxial joint were enrolled in this study. They were used for simulating the placement process and evaluating the placement feasibility of the retropharyngeal reduction plate. The atlantoaxial dislocation (AAD) of five cadaveric specimens were obtained by proper external force after dissecting ligaments. The retropharyngeal reduction plate was placed on atlantoaxial joint of cadaveric specimens. The X-ray and three-dimensional (3D) spiral CT were used for evaluating the placement safety of retropharyngeal reduction plate. The DICOM data was obtained after 3D spiral CT scanning for the morphometric trajectory analysis. RESULTS: The reduction plates were successfully placed on the atlantoaxial joint of five cadaveric specimens through the retropharyngeal approach, respectively. The X-ray and 3D spiral CT showed the accurate screw implantation and satisfying plate placement. The length of the left/right atlas screw trajectory (L/RAT) was, respectively, 1.73 ± 0.01 cm (LAT) and 1.71 ± 0.02 cm (RAT). The length of odontoid screw trajectory (OST) was 1.38 ± 0.02 cm. The length of the left/right axis screw trajectory (L/RAXT) was, respectively, 1.67 ± 0.02 cm (LAXT) and 1.67 ± 0.01 cm (RAXT). There was no statistical significance between left side and right side in terms of AT and AXT (P > 0.05). The angles of atlas screw trajectory angle (ASTA), axis screw trajectory angle (AXSTA), and odontoid screw trajectory angle (OSTA) were 38.04° ± 2.03°, 56.92° ± 2.66°, and 34.78° ± 2.87°, respectively. CONCLUSION: The cadaveric test showed that the retropharyngeal reduction plate is feasible to place on the atlantoaxial joint, which is also a safe treatment choice for atlantoaxial dislocation. The meticulous preoperative planning of screw trajectory based on individual differences was also vital to using this technique.
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Articulación Atlantoaxoidea , Luxaciones Articulares , Fusión Vertebral , Articulación Atlantoaxoidea/diagnóstico por imagen , Articulación Atlantoaxoidea/cirugía , Placas Óseas , Tornillos Óseos , Cadáver , Humanos , Luxaciones Articulares/diagnóstico por imagen , Luxaciones Articulares/cirugía , Tomografía Computarizada por Rayos XRESUMEN
Anterior decompression and fusion is an established procedure in surgical treatment for multilevel cervical spondylotic myelopathy (MCSM). However, contiguous corpectomies and fusion (CCF) often induce postoperative complications such as nonunion, graft subsidence, and loss of lordotic alignment. As an alternative, noncontiguous corpectomies or one-level corpectomy plus adjacent-level discectomy with retention of an intervening body has been developed recently. In this study, we prospectively compared noncontiguous anterior decompression and fusion (NADF) and CCF for MCSM in terms of surgical invasiveness, clinical and radiographic outcomes, and complications. From January 2005 to June 2007, 105 patients with MCSM were randomized to NADF group (n = 55) and CCF group (n = 50), and followed up for average 31.5 months (range 24-48 months). Average operative time and blood loss decreased significantly in the NADF group as compared with those in the CCF group (p < 0.05 and <0.001, respectively). For VAS, within 3 months postoperatively, there was no significant difference between the two groups. But at 6 months after surgery and final follow-up, VAS improved significantly in NADF group than that in CCF group (p < 0.05). No significant difference of JOA score was observed between the two groups at every collection time. In NADF group, all 55 cases obtained fusion at 1 year after operation (average 5.1 months). In CCF group, 48 cases achieved fusion 1 year postoperatively, but the other 2 cases were performed posterior stabilization and achieved fusion 6 months later. The differences of cervical lordosis between two groups were insignificant at the same follow-up time. But the loss of lordosis and height of fusion segments in 6 months postoperatively and final follow-up were significantly more in CFF group than in NADF group (p < 0.001). Complications were similar in both groups. But in CCF group three cases needed reoperation, one case with extradural hematoma was immediately re-operated after anterior decompression and two cases mentioned above were performed posterior stabilization at 1 year postoperatively. In conclusion, in the patients with MCSM, without developmental stenosis and continuous or combined ossification of posterior longitudinal ligaments, NADF and CCF showed an identical effect of decompression. In terms of surgical time, blood loss, VAS, fusion rate and cervical alignment, NADF was superior compared with CCF.
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Vértebras Cervicales/cirugía , Laminectomía/métodos , Fusión Vertebral/métodos , Espondilosis/cirugía , Anciano , Vértebras Cervicales/diagnóstico por imagen , Discectomía/efectos adversos , Discectomía/métodos , Femenino , Humanos , Laminectomía/efectos adversos , Masculino , Persona de Mediana Edad , Osificación del Ligamento Longitudinal Posterior/complicaciones , Osificación del Ligamento Longitudinal Posterior/diagnóstico por imagen , Osificación del Ligamento Longitudinal Posterior/cirugía , Dimensión del Dolor , Dolor Postoperatorio/etiología , Estudios Prospectivos , Radiografía , Reoperación , Fusión Vertebral/efectos adversos , Estenosis Espinal/complicaciones , Estenosis Espinal/diagnóstico por imagen , Estenosis Espinal/cirugía , Espondilosis/complicaciones , Espondilosis/diagnóstico por imagen , Resultado del TratamientoRESUMEN
Trees in the Morus genera belong to the Moraceae family. To better understand the species status of genus Morus and to provide information for studies on evolutionary biology within the genus, the complete chloroplast (cp) genomes of M. cathayana and M. multicaulis were sequenced. The plastomes of the two species are 159,265 bp and 159,103 bp, respectively, with corresponding 83 and 82 simple sequence repeats (SSRs). Similar to the SSRs of M. mongolica and M. indica cp genomes, more than 70% are mononucleotides, ten are in coding regions, and one exhibits nucleotide content polymorphism. Results for codon usage and relative synonymous codon usage show a strong bias towards NNA and NNT codons in the two cp genomes. Analysis of a plot of the effective number of codons (ENc) for five Morus spp. cp genomes showed that most genes follow the standard curve, but several genes have ENc values below the expected curve. The results indicate that both natural selection and mutational bias have contributed to the codon bias. Ten highly variable regions were identified among the five Morus spp. cp genomes, and 154 single-nucleotide polymorphism mutation events were accurately located in the gene coding region.
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Recently, more attentions have been focused on the exploration of hemicelluloses in the paper industry. In this work, xylan-grafted-polyacrylamide (xylan-g-PAM) biopolymers were synthesized by the graft copolymerization of xylan with acrylamide, and their interaction with fibers was also investigated to improve waste newspaper pulp properties with or without cationic fiber fines. The influences of synthesis conditions were studied on the grafting ratio and the grafting efficiency of biopolymers. Prepared biopolymers were characterized by FTIR, 13C NMR, TGA and rheology. It was found that the grafting of PAM on xylan was conductive to improve xylan properties, such as the solubility in water, rheological features, and thermal stability, and the maximum grafting ratio was achieved to 14.7%. Moreover, xylan-g-PAM could obviously enhance the mechanical properties of waste paper pulps. Xylan-g-PAM also played the dominant role in increasing the strength of paper in the combination with prepared cationic fine fibers. When the amounts of xylan-g-PAM and cationic fiber fines were 1.0 wt % and 0.5 wt %, the mechanical properties such as the tensile index was increased by 49.09%, tear index was increased by 36.54%, and the burst index was increased by 20.67%, when compared with the control handsheets. Therefore, xylan-g-PAM as the new biopolymer could be promising in the application of strength agents for the paper industry as well as cationic fiber fines.
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Among the natural macromolecules potentially used as the scaffold material in hydrogels, xylan has aroused great interest in many fields because of its biocompatibility, low toxicity, and biodegradability. In this work, new pH and thermoresponsive hydrogels were prepared by the cross-linking polymerization of maleic anhydride-modified xylan (MAHX) with N-isopropylacrylamide (NIPAm) and acrylic acid (AA) under UV irradiation to form MAHX-g-P(NIPAm-co-AA) hydrogels. The pore volume, the mechanical properties, and the release rate for drugs of hydrogels could be controlled by the degree of substitution of MAHX. These hydrogels were characterized by swelling ability, lower critical solution temperature (LCST), Fourier-transform infrared (FTIR), and SEM. Furthermore, the cumulative release rate was investigated for acetylsalicylic acid and theophylline, as well as the cytocompatibility MAHX-based hydrogels. Results showed that MAHX-based hydrogels exhibited excellent swelling-deswelling properties, uniform porous structure, and the temperature/pH dual sensitivity. In vitro, the cumulative release rate of acetylsalicylic acid for MAHX-based hydrogels was higher than that for theophylline, and in the gastrointestinal sustained drug release study, the acetylsalicylic acid release rate was extremely slow during the initial 3 h in the gastric fluid (24.26%), and then the cumulative release rate reached to 90.5% after sustained release for 5 h in simulated intestinal fluid. The cytotoxicity experiment demonstrated that MAHX-based hydrogels could promote cell proliferation and had satisfactory biocompatibility with NIH3T3 cells. These results indicated that MAHX-based hydrogels, as new drug carriers, had favorable behavior for intestinal-targeted drug delivery.
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OBJECTIVE: To explore a way of the gene therapy for acute spinal cord injury (ASCI) by vivo transfection of exogenous gene into spinal cord tissue. METHODS: Twenty-four rats of SD were divided into experiment group and control group (each group had 12 rats). After anaesthesia by abdominal cavity, lamina of thoracic vertebra of all rats were cut-open in prone position. Complex of plasmid and report gene-Lac Z, and plasmid without report gene-Lac Z were respectively injected into cavum subdural of SD rats of experiment group and control group by cation liposome (DOTAP) encapsulation. The rats were killed at the 2nd week after operation, spinal cord tissue of injected segments were detected by reverse transcription-polymerase chain raction (RT-PCR) and immunohistochemistry. RESULTS: In experiment group, positive staining of beta-galactosidase can be clearly observed in neuron and glia cell of rat's spinal cord by immunohistochemistry detection. Lac Z mRNA in same area was also detected by RT-PCR. But, in control group, no above-mentioned positive results were found. CONCLUSION: Effective transfection of exogenous gene in vivo into spinal cord is a new hot spot for treatment of SCI. Thus certain nerve growth factor imput partly area of spinal cord injury can promote central nerve regrowth and avoid early secondary injury.
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Terapia Genética , Operón Lac , Traumatismos de la Médula Espinal/terapia , Médula Espinal/metabolismo , Transfección , beta-Galactosidasa/análisis , Enfermedad Aguda , Animales , ARN Mensajero/análisis , Ratas , Ratas Sprague-DawleyRESUMEN
MicroRNAs (miRNAs) constitute a class of noncoding RNAs that post-transcriptionally regulate gene expression. Recent evidence indicates that many miRNAs function as oncogenes or tumor suppressors by negatively regulating their target genes. In our previous study, using miRNA microarray analysis, we found that miRNA-182 (miR-182) was significantly downregulated in human gastric adenocarcinoma tissue samples. Here, we confirmed the downregulation of miR-182 in a larger sample of gastric tissue samples. Overexpression of miR-182 suppressed the proliferation and colony formation of gastric cancer cells. An oncogene, encoding cAMP-responsive element binding protein 1 (CREB1), serves as a direct target gene of miR-182. A fluorescent reporter assay confirmed that miR-182 binds specifically to the predicted site of the CREB1 mRNA 3'-UTR. When miR-182 was overexpressed in gastric cancer cell lines, both the mRNA and protein levels of CREB1 were depressed. Furthermore, CREB1 was present at a high level in human gastric adenocarcinoma tissues, and this was inversely correlated with miR-182 expression. Ectopic expression of CREB1 overcame the suppressive phenotypes of gastric cancer cells caused by miR-182. These results indicate that miR-182 targets the CREB1 gene and suppresses gastric adenocarcinoma cell growth, suggesting that miR-182 shows tumor-suppressive activity in human gastric cancer.
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Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , MicroARNs/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patología , Regiones no Traducidas 3' , Adenocarcinoma/genética , Anciano , Proliferación Celular , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , MicroARNs/genética , Persona de Mediana Edad , Neoplasias Gástricas/genéticaRESUMEN
STUDY DESIGN: A retrospective study. OBJECTIVE: To evaluate the clinical outcome, effectiveness, and security of the surgical management of acute thoracolumbar burst fracture with corpectomy, titanic mesh autograft, and Z-plate fixation by anterior approach. SUMMARY OF BACKGROUND DATA: Many surgical methods were adopted to treat acute burst thoracolumbar fracture. But the optimal surgical management remains controversial. METHODS: A retrospective review of a consecutive series of 48 patients with thoracolumbar burst fracture treated with anterior corpectomy, titanic mesh autograft, and Z-plate internal fixation was carried out. Preoperative clinical and radiographic data of all cases were originally collected. Surgical indications were motor neurologic deficit and thoracolumbar column instability. Twenty-two patients (45.8%) with acute thoracolumbar burst fractures presented with a neurologic deficit. The postoperative recovery of neural function, restoration of anterior cortex collapse, kyphotic angle, and spinal canal compromise were observed. RESULTS: The preoperative kyphotic angle was improved to a mean of 5.6°, radiographic height restored to 95.8% of the adjacent normal levels, and canal compromise was 0%. None of the patients had neurologic deterioration. Mean follow-up time was 32.4 months (range, 24-47 months). All 22 patients with neurologic deficit demonstrated at least one Frankel grade improvement on final observation, with 16 (73%) patients had accomplished complete neurologic recovery. Forty-six (96%) patients reported minimal or no pain at final follow-up observation, and 40 (83%) patients who had been working before injury returned to original work. CONCLUSION: The authors considered spinal cord decompression with anterior corpectomy and stability reconstruction with titanic mesh autograft and Z-plate fixation at same time in one incision as an effective technique for unstable thoracolumbar burst fracture with and without neurologic deficit.