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1.
Front Bioeng Biotechnol ; 12: 1358181, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38812913

RESUMO

Objective: The objective of the present study is to conduct a comparative analysis of the biomechanical advantages and disadvantages associated with a biplanar double support screw (BDSF) internal fixation device. Methods: Two distinct femoral neck fracture models, one with a 30° angle and the other with a 70° angle, were created using a verified and effective finite element model. Accordingly, a total of eight groups of finite element models were utilized, each implanted with different configurations of fixation devices, including distal screw 150° BDSF, distal screw 165° BDSF, 3 CLS arranged in an inverted triangle configuration, and 4 CLS arranged in a "α" configuration. Subsequently, the displacement and distribution of Von Mises stress (VMS) in the femur and internal fixation device were assessed in each fracture group under an axial load of 2100 N. Results: At Pauwels 30° Angle, the femur with a 150°-BDSF orientation exhibited a maximum displacement of 3.17 mm, while the femur with a 165°-BDSF orientation displayed a maximum displacement of 3.13 mm. When compared with the femoral neck fracture model characterized by a Pauwels Angle of 70°, the shear force observed in the 70° model was significantly higher than that in the 30° model. Conversely, the stability of the 30° model was significantly superior to that of the 70° model. Furthermore, in the 70° model, the BDSF group exhibited a maximum femur displacement that was lower than both the 3CCS (3.46 mm) and 4CCS (3.43 mm) thresholds. Conclusion: The biomechanical properties of the BDSF internal fixation device are superior to the other two hollow screw internal fixation devices. Correspondingly, superior biomechanical outcomes can be achieved through the implementation of distal screw insertion at an angle of 165°. Thus, the BDSF internal fixation technique can be considered as a viable closed reduction internal fixation technique for managing femoral neck fractures at varying Pauwels angles.

2.
Heliyon ; 10(5): e26726, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38434291

RESUMO

Purpose: This study aimed to compare the biomechanical effects of different bone cement distribution methods on osteoporotic vertebral compression fractures (OVCF). Patients and methods: Raw CT data from a healthy male volunteer was used to create a finite element model of the T12-L2 vertebra using finite element software. A compression fracture was simulated in the L1 vertebra, and two forms of bone cement dispersion (integration group, IG, and separation group, SG) were also simulated. Six types of loading (flexion, extension, left/right bending, and left/right rotation) were applied to the models, and the stress distribution in the vertebra and intervertebral discs was observed. Additionally, the maximum displacement of the L1 vertebra was evaluated. Results: Bone cement injection significantly reduced stress following L1 vertebral fractures. In the L1 vertebral body, the maximum stress of SG was lower than that of IG during flexion, left/right bending, and left/right rotation. In the T12 vertebral body, compared with IG, the maximum stress of SG decreased during flexion and right rotation. In the L2 vertebral body, the maximum stress of SG was the lowest under all loading conditions. In the T12-L1 intervertebral disc, compared with IG, the maximum stress of SG decreased during flexion, extension, and left/right bending and was basically the same during left/right rotation. However, in the L1-L2 intervertebral discs, the maximum stress of SG increased during left/right rotation compared with that of IG. Furthermore, the maximum displacement of SG was smaller than that of IG in the L1 vertebral bodies under all loading conditions. Conclusions: SG can reduce the maximum stress in the vertebra and intervertebral discs, offering better biomechanical performance and improved stability than IG.

3.
Front Endocrinol (Lausanne) ; 14: 1259095, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37900139

RESUMO

Objective: The aim of this study was to investigate the biomechanical stress of sandwich vertebrae (SVs) and common adjacent vertebrae in different degrees of spinal mobility in daily life. Materials and methods: A finite element model of the spinal segment of T10-L2 was developed and validated. Simultaneously, T11 and L1 fractures were simulated, and a 6-ml bone cement was constructed in their center. Under the condition of applying a 500-N axial load to the upper surface of T10 and immobilizing the lower surface of L2, moments were applied to the upper surface of T10, T11, T12, L1, and L2 and divided into five groups: M-T10, M-T11, M-T12, M-L1, and M-L2. The maximum von Mises stress of T10, T12, and L2 in different groups was calculated and analyzed. Results: The maximum von Mises stress of T10 in the M-T10 group was 30.68 MPa, 36.13 MPa, 34.27 MPa, 33.43 MPa, 26.86 MPa, and 27.70 MPa greater than the maximum stress value of T10 in the other groups in six directions of load flexion, extension, left and right lateral bending, and left and right rotation, respectively. The T12 stress value in the M-T12 group was 29.62 MPa, 32.63 MPa, 30.03 MPa, 31.25 MPa, 26.38 MPa, and 26.25 MPa greater than the T12 stress value in the other groups in six directions. The maximum stress of L2 in M-T12 in the M-L2 group was 25.48 MPa, 36.38 MPa, 31.99 MPa, 31.07 MPa, 30.36 MPa, and 32.07 MPa, which was greater than the stress value of L2 in the other groups. When the load is on which vertebral body, it is subjected to the greatest stress. Conclusion: We found that SVs did not always experience the highest stress. The most stressed vertebrae vary with the degree of curvature of the spine. Patients should be encouraged to avoid the same spinal curvature posture for a long time in life and work or to wear a spinal brace for protection after surgery, which can avoid long-term overload on a specific spine and disrupt its blood supply, resulting in more severe loss of spinal quality and increasing the possibility of fractures.


Assuntos
Fraturas por Compressão , Fraturas da Coluna Vertebral , Humanos , Análise de Elementos Finitos , Coluna Vertebral , Fraturas por Compressão/cirurgia , Fenômenos Biomecânicos
4.
Polymers (Basel) ; 15(19)2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37835933

RESUMO

High-strength large-volume marine concrete is a critical material required for the construction of large-span sea-crossing bridges. However, the widespread issue of cracking in this concrete type significantly impacts the durability and load-bearing capacity of concrete structures. Dealing with these cracks not only delays construction schedules but also increases project costs. Addressing these pressing technical issues, this project proposes the use of newly developed high-modulus heat-shrinkable fibers (polyethylene terephthalate fiber, also known as PET fiber) from the textile industry. These fibers utilize the heat generated during the hydration of large-volume concrete to trigger its contraction, applying three-dimensional micro-prestressing stress to enhance its crack resistance, while simultaneously incorporating prewetted aggregates with high-performance micro-porous structures and utilizing their internal curing effect to reduce concrete shrinkage. This helps to minimize the loss of micro-prestressing stress caused by concrete shrinkage and creep. This synergistic approach aims to improve the crack resistance of high-strength large-volume marine concrete. By employing modern testing and simulation analysis techniques, this study aims to uncover the mechanism by which the heat-shrinkable fibers exert micro-prestressing stress on concrete and the water release mechanism of internal curing aggregates during the temperature rise and fall stages of large-volume concrete. It seeks to elucidate the cooperative regulation of the microstructure and performance enhancement mechanisms of high-strength large-volume marine concrete by the heat-shrinkable fibers and internal curing aggregates. This research will lead to the development of novel methods for the design and crack control of high-strength large-volume marine concrete, which will be validated through engineering demonstrations. The outcomes of this study will provide theoretical foundations and technical support for the preparation of the crack-resistant large-volume marine concrete used in large-span bridges.

5.
BMC Musculoskelet Disord ; 24(1): 674, 2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37620843

RESUMO

OBJECTIVE: Analysis of the risk factors affecting hip function and complications after femoral neck system (FNS) surgery for femoral neck fractures is of great significance for improving the procedure's efficacy. METHODS: The data of patients with femoral neck fractures who underwent FNS surgery in our hospital between October 2019 and October 2020 were retrospectively analyzed. Age, gender, time from injury to operation, fracture classification, operation time, fracture reduction, and postoperative weight-bearing time information were set as potential factors that may affect the results. Hip Harris scores were performed at 12 months postoperatively, and postoperative complication data (e.g., femoral head necrosis, nonunion, and femoral neck shortness) were collected. The risk factors affecting hip function and complications after FNS surgery were predicted using linear and logistic regression analyses. RESULTS: A total of 69 cases of femoral neck fracture were included, with an average age of 56.09 ± 11.50 years. The linear analysis demonstrated that the age and fracture type of the patients were the risk factors affecting the Harris score of the hip joint after FNS surgery. Older patients with displaced femoral neck fractures had an inferior postoperative hip function. In addition, fracture type, reduction of the femoral neck, and postoperative weight-bearing significantly impacted postoperative complications. Displaced fractures, negative fixation, and premature weight-bearing (< 6 weeks) were risk factors for postoperative complications. The Harris score of patients with a shortened femoral neck in the included cases was not significantly different from that of patients without shortening (P = 0.25). CONCLUSIONS: Advanced age and fracture type are important evaluation indicators of the Harris score after FNS internal fixation of femoral neck fractures in young patients. Fracture type, fracture reduction, and postoperative weight-bearing time are risk factors for complications after FNS.


Assuntos
Fraturas do Colo Femoral , Colo do Fêmur , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Fraturas do Colo Femoral/cirurgia , Fatores de Risco , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Articulação do Quadril/diagnóstico por imagem , Articulação do Quadril/cirurgia
6.
Orthop Surg ; 15(7): 1763-1771, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37254237

RESUMO

OBJECTIVE: Bone cement leakage is a major complication of percutaneous vertebroplasty (PVP) while treating Kümmell's disease and it is a focus of close attention during the surgical procedure. The study aimed to investigate whether pre-injecting a composite of bone cement and gelatine sponge (the "bone cement-gelatine sponge composite") before injecting bone cement during PVP aids in lowering the leakage rate in stage I and II Kümmell's disease. METHODS: This prospective analysis evaluated 74 patients with stage I and II Kümmell's disease who underwent PVP treatment at our hospital from December 2019 to December 2021. The participants were divided randomly into groups based on whether the bone cement-gelatine sponge composite was used during the surgery. The two groups were the bone cement-gelatine sponge composite group (GS group, comprising 37 patients) and the no bone cement-gelatine sponge composite group (N-GS group, comprising 37 patients). The independent samples t-test and chi-square test were employed to compare general information, operative time, cement injection volume, intraoperative bleeding, and bone cement leakage between the two groups. Additionally, the visual analogue scale (VAS) score, Oswestry disability index (ODI), anterior vertebral height ratio (AVHR), and the kyphotic Cobb angle were compared between the two groups at the preoperative, 2 days postoperative, and 6 months postoperative stages using repeated measures analysis of variance. RESULTS: All patients were followed up for more than 6 months, with an average of (11.19 ± 2.21) months. No significant differences were observed in terms of the operative time, cement injection volume, and intraoperative bleeding between the two groups (P > 0.05). The incidence of bone cement leakage in the N-GS group (32.43%) was significantly higher than that in the GS group (5.41%), and the difference was statistically significant (P < 0.05). The VAS score and ODI of the two groups at postoperative 2 days and 6 months improved significantly (P < 0.05). The AVHR and kyphotic Cobb angle were corrected to a certain extent (P < 0.05); however, no significant difference was observed between the two groups (P > 0.05). CONCLUSION: The bone cement-gelatine sponge composite intravertebral prefilling technique can lower bone cement leakage in stage I and II Kümmell's disease and can also relieve pain and improve vertebral body height.


Assuntos
Fraturas por Compressão , Cifoplastia , Cifose , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Espondilose , Vertebroplastia , Humanos , Fraturas da Coluna Vertebral/cirurgia , Vertebroplastia/métodos , Cimentos Ósseos , Estudos de Viabilidade , Resultado do Tratamento , Cifose/etiologia , Espondilose/complicações , Fraturas por Compressão/cirurgia , Estudos Retrospectivos , Fraturas por Osteoporose/cirurgia , Cifoplastia/métodos
7.
Front Endocrinol (Lausanne) ; 14: 1072087, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37033237

RESUMO

Objective: To investigate the correlation analysis of larger side bone cement volume/vertebral body volume ratio (LSBCV/VBV%) with adjacent vertebral compression fracture (AVCF) in percutaneous vertebroplasty (PVP) for osteoporotic vertebral compression fracture (OVCF). Methods: A retrospective analysis of 245 OVCF patients who underwent PVP treatment from February 2017 to February 2021, including 85 males and 160 females. The age ranged from 60 to 92 years, with a mean of (70.72 ± 7.03) years. According to whether AVCF occurred after surgery, they were divided into 38 cases in the AVCF group (fracture group) and 207 cases in the no AVCF group (non-fracture group). The correlation between gender, age, bone mineral density (BMD), body mass index (BMI), thoracolumbar segment fracture, bone cement disc leakage, LSBCV, bone cement volume (BCV), VBV, LSBCV/VBV ratio (LSBCV/VBV%), and BCV/VBV% and AVCF were analyzed in both groups. Risk factors for AVCF after PVP were analyzed by multifactorial logistic regression, and then the receiver operating characteristic curves (ROC curves) were plotted to identify the critical value of LSBCV/VBV%. Results: 38 patients (15.5%) developed AVCF postoperatively. Univariate analysis showed that BMD, bone cement disc leakage, LSBCV, and LSBCV/VBV% were risk factors for AVCF after PVP (P<0.05), while gender, age, BMI, thoracolumbar segment fracture, BCV, VBV, and BCV/VBV% were not significantly different in both groups (P>0.05). Multifactorial logistic regression analysis revealed that BMD, bone cement disc leakage, and LSBCV/VBV% were independent risk factors for AVCF after PVP (P<0.05). According to the ROC curve, the LSBCV/VBV% had an area under the curve of 71.6%, a sensitivity and specificity of 89.5% and 51.7%, respectively, and a critical value of 13.82%. Conclusion: BMD, bone cement disc leakage and LSBCV/VBV% are independent risk factors for AVCF after PVP. With LSBCV/VBV at 13.82%, the incidence of AVCF significantly increased.


Assuntos
Fraturas por Compressão , Fraturas da Coluna Vertebral , Vertebroplastia , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Fraturas por Compressão/etiologia , Fraturas por Compressão/cirurgia , Fraturas da Coluna Vertebral/etiologia , Fraturas da Coluna Vertebral/cirurgia , Fraturas da Coluna Vertebral/epidemiologia , Cimentos Ósseos/efeitos adversos , Estudos Retrospectivos , Corpo Vertebral , Vertebroplastia/efeitos adversos
8.
Biomed Eng Online ; 22(1): 20, 2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36859241

RESUMO

OBJECTIVE: The purpose of this study was to compare the biomechanical and clinical results of two surgical methods for the treatment of vertical femoral neck fractures: Femoral neck system (FNS) and traditional three cannulated cancellous screws (CCS). METHODS: First, we developed three different vertical femoral neck fracture models for the finite element analysis, with angles of 55°, 65°, and 75°, respectively. Two experimental groups were set up: the FNS group and the CCS group. Each fracture group was tested under axial loads of 2100 N to measure the femur's displacement, Von Mises stress (VMS), and its internal fixation components. Secondly, we retrospectively included the cases of vertical femoral neck fractures with FNS and CCS in our hospital from May 2019 to May 2021. In this study, we compared the duration of intraoperative fluoroscopy, operative time, hospital stay, fracture healing time, Hemoglobin loss, Harris score of hip joint function, and postoperative complications among patients undergoing hip joint replacement. RESULTS: In terms of finite element analysis, FNS has better anti-displacement stability than CCS at 55°and 65°, while FNS is greater than CCS in Von Mises stress. Clinically, we followed up on 87 patients for an average of 12 months. FNS was superior to traditional CCS in fracture healing time, operation time, fluoroscopy duration, fracture healing time, and Harris hip function score. CONCLUSION: FNS is superior to traditional CCS in biomechanical and clinical aspects of treating vertical femoral neck fractures. There is potential for FNS to become a new treatment option for vertical femoral neck fractures.


Assuntos
Fraturas do Colo Femoral , Colo do Fêmur , Humanos , Análise de Elementos Finitos , Estudos Retrospectivos , Fluoroscopia
9.
Opt Express ; 30(22): 40569-40583, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36298987

RESUMO

Quantum key distribution (QKD) and quantum key agreement (QKA) are two main branches of key establishment in quantum cryptography. However, the research of QKA falls far behind that of QKD, especially in practicability. The main reason is that QKA needs to resist not only the outside eavesdropping but also the participant cheating. Resisting dishonest participant is more difficult than resisting outside eavesdropping, especially when the apparatuses are imperfect. Actually, existing QKA protocols cannot tolerate the channel loss and have to rely on stable quantum storage. To solve this problem, we give a new quantum multi-party key agreement protocol based on the error-correcting code. Our protocol is loss tolerant, and the participants can measure the received qubits immediately in one of two conjugate bases, without storage, so our protocol can eliminate the requirement of quantum storage. Besides, our protocol is more fair because it can partially discriminate dishonest participants' cheating from outside eavesdropping (previously, these two attacks are generally checked simultaneously via decoy states but cannot be discriminated), as a result, dishonest participants generally will not cheat at the cost of losing good reputation.

10.
Front Surg ; 9: 975832, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36034386

RESUMO

Objective: The study aimed to investigate the effect of the type of bone cement distribution on clinical outcomes following percutaneous vertebroplasty (PVP) for osteoporotic vertebral compression fractures (OVCF) in the elderly. Methods: Retrospective analysis of 160 patients diagnosed with OVCF who underwent PVP treatment from March 2018 to December 2020. Based on the kind of postoperative bone cement distribution, bone cement was classified as types I, II, III, IV, and V. Visual Analog Scale (VAS), Oswestry Disability Index (ODI), Cobb angle, anterior vertebral height ratio, refracture rate of injured vertebrae, and incidence of adjacent vertebral fractures were compared for the five types before and after three days, and one year of operation. Results: VAS and ODI at three days and one year postoperative were significantly lower than those preoperative (P < 0.05) for all five distribution types. VAS and ODI for types I, II, and III were lower at one year postoperatively than for types IV and V (P < 0.05). There was no significant difference in Cobb angle and anterior vertebral body height ratio between preoperative and three days postoperative groups (P < 0.05); however, there were significant differences between three days and one-year postoperative and preoperative groups (P < 0.05). Following one year of surgery, the Cobb angle and the anterior vertebral height ratio of types IV and V were significantly different from those of types I, II, and III (P < 0.05), and there was a statistically significant difference between types IV and V (P < 0.05). In terms of the incidence of injured vertebral refractures and adjacent vertebral fractures, the evenly distributed types I, II, and III were significantly lower than the unevenly distributed types IV and V, and the incidence of type V was higher (P < 0.05). Conclusions: The clinical efficacy of cement distribution following PVP of types I, II, and III is better than that of types IV and V, which can better relieve pain with long-lasting efficacy and minimize the occurrence of refractures of injured vertebrae and adjacent vertebral body fractures.

11.
Front Immunol ; 13: 849468, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35669769

RESUMO

Objective: This study aims to investigate the potential prognostic significance of programmed death ligand-1 (PD-L1) protein expression in tumor cells of breast cancer patients received neoadjuvant chemotherapy (NACT). Methods: Using semiquantitative immunohistochemistry, the PD-L1 protein expression in breast cancer tissues was analyzed. The correlations between PD-L1 protein expression and clinicopathologic characteristics were analyzed using Chi-square test or Fisher's exact test. The survival curve was stemmed from Kaplan-Meier assay, and the log-rank test was used to compare survival distributions against individual index levels. Univariate and multivariate Cox proportional hazards regression models were accessed to analyze the associations between PD-L1 protein expression and survival outcomes. A predictive nomogram model was constructed in accordance with the results of multivariate Cox model. Calibration analyses and decision curve analyses (DCA) were performed for the calibration of the nomogram model, and subsequently adopted to assess the accuracy and benefits of the nomogram model. Results: A total of 104 breast cancer patients received NACT were enrolled into this study. According to semiquantitative scoring for IHC, patients were divided into: low PD-L1 group (61 cases) and high PD-L1 group (43 cases). Patients with high PD-L1 protein expression were associated with longer disease free survival (DFS) (mean: 48.21 months vs. 31.16 months; P=0.011) and overall survival (OS) (mean: 83.18 months vs. 63.31 months; P=0.019) than those with low PD-L1 protein expression. Univariate and multivariate analyses indicated that PD-L1, duration of neoadjuvant therapy, E-Cadherin, targeted therapy were the independent prognostic factors for patients' DFS and OS. Nomogram based on these independent prognostic factors was used to evaluate the DFS and OS time. The calibration plots shown PD-L1 based nomogram predictions were basically consistent with actual observations for assessments of 1-, 3-, and 5-year DFS and OS time. The DCA curves indicated the PD-L1 based nomogram had better predictive clinical applications regarding prognostic assessments of 3- and 5-year DFS and OS, respectively. Conclusion: High PD-L1 protein expression was associated with significantly better prognoses and longer DFS and OS in breast cancer patients. Furthermore, PD-L1 protein expression was found to be a significant prognostic factor for patients who received NACT.


Assuntos
Antígeno B7-H1 , Neoplasias da Mama , Antígeno B7-H1/metabolismo , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Intervalo Livre de Doença , Feminino , Humanos , Terapia Neoadjuvante , Nomogramas
12.
Front Immunol ; 13: 831848, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35320931

RESUMO

Objective: This study aims at investigating the potential prognostic significance of the breast immune prognostic index (BIPI) in breast cancer patients who received neoadjuvant chemotherapy (NACT). Methods: The optimal cutoff value was calculated through the receiver operating characteristic curve (ROC). The correlations between BIPI and clinicopathologic characteristics were determined by the chi-square test or Fisher's exact test. The Kaplan-Meier method was used to estimate the survival probability, and the log-rank test was used to analyze the differences in the survival probability among patients. The univariate and multivariate Cox proportional hazard regression model was used to screen the independent prognostic factors. A prognostic nomogram for disease-free survival (DFS) and overall survival (OS) was built on the basis of the multivariate analyses. Furthermore, the calibration curve and decision curve analysis (DCA) were used to assess the predictive performance of the nomogram. Results: All enrolled patients were split into three subgroups based on the BIPI score. The mean DFS and OS of the BIPI score 0 group and BIPI score 1 group were significantly longer than those of the BIPI score 2 group (42.02 vs. 38.61 vs. 26.01 months, 77.61 vs. 71.83 vs. 53.15 months; p < 0.05). Univariate and multivariate analyses indicated that BIPI was an independent prognostic factor for patients' DFS and OS (DFS, hazard ratio (HR): 6.720, 95% confidence interval (CI): 1.629-27.717; OS, HR: 8.006, 95% CI: 1.638-39.119). A nomogram with a C-index of 0.873 (95% CI: 0.779-0.966) and 0.801 (95% CI: 0.702-0.901) had a favorable performance for predicting DFS and OS survival rates for clinical use by combining immune scores with other clinical features. The calibration curves at 1-, 3-, and 5-year survival suggested a good consistency between the predicted and actual DFS and OS probability. The DCA demonstrated that the constructed nomogram had better clinical predictive usefulness than only BIPI in predictive clinical applications of 5-year DFS and OS prognostic assessments. Conclusions: The patients with low BIPI score have better prognoses and longer DFS and OS. Furthermore, the BIPI-based nomogram may serve as a convenient prognostic tool for breast cancer and help in clinical decision-making.


Assuntos
Neoplasias da Mama , Terapia Neoadjuvante , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Intervalo Livre de Doença , Feminino , Humanos , Terapia Neoadjuvante/métodos , Nomogramas , Prognóstico
13.
Neoplasma ; 68(6): 1245-1256, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34641696

RESUMO

Cancer pathogenesis is influenced by epigenetic alterations mediated by circular RNAs (circRNAs). In this study, we aimed to investigate the regulatory mechanisms and cytological function of hsa_circ_0006470/miR-27b-3p in gastric cancer (GC). circRNA and microRNA expressions in cancer cells were measured by the qRT-PCR method. A dual-luciferase reporter assay was performed to validate the binding of hsa_circ_0006470 with miR-27b-3p. hsa_circ_0006470 was silenced in AGS cells, and proliferation, migration, and invasion were tested via the CCK-8 assay and Transwell system, respectively. The autophagy in GC cells was assessed by marker protein detection and transmission electron microscope. The results showed that hsa_circ_0006470 expression was significantly elevated in GC cells, which was mainly distributed in cytoplasmic components and could directly bind with miR-27b-3p in GC cells. Silencing of hsa_circ_0006470 repressed cell proliferation, migration, and invasion, which may be through regulating miR-27b-3p/Receptor tyrosine kinase-like orphan receptor 1 (ROR1). Silencing of hsa_circ_0006470 also elevated LC3II and Beclin-1 and suppressed p62 protein abundances, which subsequently induced autophagy in AGS cells. Furthermore, we found that hsa_circ_0006470 promotes phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PI3KCA) expressing by sponging miR-27b-3p. In conclusion, hsa_circ_0006470 promoted GC cell proliferation and migration through targeting miR-27b-3p and suppressing autophagy machinery.


Assuntos
MicroRNAs , RNA Circular , Neoplasias Gástricas , Movimento Celular/genética , Proliferação de Células/genética , Humanos , MicroRNAs/genética , RNA Circular/genética , Receptores Órfãos Semelhantes a Receptor Tirosina Quinase , Neoplasias Gástricas/genética , Células Tumorais Cultivadas
14.
Front Cell Dev Biol ; 9: 656741, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33859986

RESUMO

OBJECTIVE: Prognostic nutritional index (PNI), calculated as serum albumin (ALB) (g/L) + 5 × total lymphocyte count (109/L), is initially used to evaluate nutritional status in patients undergoing surgery and may evaluate the therapeutic effects and predict the survival of various solid tumors. The present study aimed to evaluate the potential prognostic significance of PNI in breast cancer patients receiving neoadjuvant chemotherapy (NACT). METHODS: A total of 785 breast cancer patients treated with neoadjuvant chemotherapy were enrolled in this retrospective study. The optimal cutoff value of PNI by receiver operating characteristic curve stratified patients into a low-PNI group (<51) and a high PNI group (≥51). The associations between breast cancer and clinicopathological variables by PNI were determined by chi-square test or Fisher's exact test. Kaplan-Meier plots and log-rank test were used to evaluate the clinical outcomes of disease-free survival (DFS) and overall survival (OS). The prognostic value of PNI was analyzed by univariate and multivariate Cox proportional hazards regression models. The toxicity of NACT was accessed by the National Cancer Institute Common Toxicity Criteria (NCI-CTC). RESULTS: The results indicated that PNI had prognostic significance by an optimal cutoff value of 51 on DFS and OS in univariate and multivariate Cox regression survival analyses. Breast cancer patients with a high PNI value had longer DFS and OS than those with a low PNI value [47.64 vs. 36.60 months, P < 0.0001, hazard ratio (HR) = 0.264, 95%CI = 0.160-0.435; 73.61 vs. 64.97 months, P < 0.0001, HR = 0.319, 95%CI = 0.207-0.491, respectively]. Furthermore, the results indicated that patients with high PNI had longer DFS and OS than those with low PNI in early stage and advanced breast cancer, especially in advanced breast cancer. The mean DFS and OS times for breast cancer patients with high PNI by the log-rank test were longer than in those with low PNI in different molecular subtypes. Moreover, the mean DFS and OS times in patients with high PNI by the log-rank test were longer than in those patients with low PNI without or with lymph vessel invasion. The common toxicities after neoadjuvant chemotherapy were hematologic and gastrointestinal reaction, and the PNI had no significance on the toxicities of all enrolled patients, except in anemia, leukopenia, and myelosuppression. CONCLUSION: Pretreatment PNI with the advantages of being convenient, noninvasive, and reproducible was a useful prognostic indicator for breast cancer patients receiving neoadjuvant chemotherapy and is a promising biomarker for breast cancer on treatment strategy decisions.

15.
J Gastrointest Oncol ; 12(1): 121-132, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33708430

RESUMO

BACKGROUND: Gastric cancer is the second leading cancer-related mortality worldwide and more effective treatment strategies are urgently needed to combat the disease. Using lipoteichoic acid (LTA) and miR-27b-3p agomir, we aimed to assess the efficacy of this combination of therapies in treating gastric cancer. METHODS: The RNA levels of miR-27b-3p, FOXO3, MET, KRAS, vascular endothelial growth factor C (VEGFC), TSC1, and P65 were analyzed by quantified-PCR (Q-PCR) and the cell viability of AGS cells was analyzed by MTT. Confirm Luciferase reporter assays were used to explore the putative miR-27b-3p binding sites and Western blot analyzed the protein level of GAPDH, VEGFC, P65, AKT, and phosphorylated-AKT (p-AKT). The level of P65 in both the cytoplasm and nucleus of AGS cells was visualized by immunofluorescence assay. Subcutaneous xenograft models of gastric cancer were established, and mice were treated with miR-27b-3p agomir, LTA, or both. Hematoxylin-eosin staining and Ki-67 immunohistochemistry analysis of tumor tissues were then performed. RESULTS: The results showed that the decreased expression of miR-27b-3p in gastric cancer cell lines inhibited the viability of AGS cells, and VEGFC was confirmed as the target of miR-27b-3p. In addition, ectopic expression of miR-27b-3p significantly inhibited the AKT pathway in AGS and N87 cells, and LTA suppressed the proliferation of gastric cancer cells by inhibiting the NF-κB pathway. In an established xenograft model, both miR-27b-3p agomir alone and LTA treatment alone inhibited tumor growth and treatment which combined the two showed an even stronger inhibitory effect. CONCLUSIONS: Taken together, the combined use of LTA and miR-27b-3p agomir exhibited a synergistic effect in the treatment of gastric cancer.

16.
JAMA Netw Open ; 3(10): e2020303, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33074325

RESUMO

Importance: Breast cancer is the most commonly diagnosed cancer and the leading cause of death in women worldwide. Yet the racial/ethnic disparity in incidences and distributions of breast cancer remains largely unknown. Objective: To examine the racial/ethnic patterns associated with the incidence of the subtypes of breast cancer and distribution of patients across clinicopathological variables. Design, Setting, and Participants: This population-based cohort study analyzed data from the Surveillance, Epidemiology, and End Results (SEER) database, which collected data from 18 SEER cancer registries that identified patients with breast cancer in the US diagnosed between January 1, 2010, and December 31, 2015. The inclusion criteria were (1) female patients with primary unilateral breast cancer who underwent surgical treatment; (2) record of estrogen receptor, progesterone receptor, and ERBB2 status; (3) record of medical history and histological subtype of the specified tumor location; and (4) data on patient race/ethnicity, lateral tumor position, tumor size, tumor TNM stage, and number of tumors. Incidence and distribution rates were identified and compared for different molecular subtypes, histological grades, pathological patterns, T stages, TNM stages, and tumor sites of breast cancers for each racial/ethnic group. Patient race/ethnicity was classified as follows: non-Hispanic White, Hispanic White, Black, Asian/Pacific Islander, American Indian/Alaskan Native, and unknown. Data were analyzed from January 1, 2010, to December 31, 2015. Main Outcomes and Measures: Incidence rates of 4 molecular subtypes: hormone receptor (HR)-positive and ERBB2-negative, HR-positive and ERBB2-positive, HR-negative and ERBB2-positive, and triple-negative breast cancer (TNBC). Data on distribution by histological grades (grades 1-4 and unknown), pathological patterns, T stages, TNM stages, and tumor sites was also extracted. Annual age-standardized incidence rates and incidence rate ratios (IRRs) were calculated with 95% CIs. Race/ethnicity case-to-case odds ratios were estimated using polytomous regression. Results: A total of 239 211 women with breast cancer were analyzed (median [interquartile range]) age, 60 [50-69] years). The annual incidence rate of all breast cancers was 31.3 (95% CI, 31.2- 31.5) per 100 000 people in non-Hispanic White women (the reference group), which was higher compared with the incidence among Black women (IRR, 1.04; 95% CI, 1.02-1.05; P < .001). The incidence rates were also lower in Asian/Pacific Islander (IRR, 0.90; 95% CI, 0.89-0.92; P < .001), American Indian/Alaskan native (IRR, 0.82; 95% CI, 0.81-0.83; P < .001), and Hispanic White women (IRR, 0.79; 95% CI, 0.75-0.83; P < .001). In Black patients, the incidences of the HR-positive and ERBB2-positive (IRR, 1.12; 95% CI, 1.08-1.16; P < .001), HR-negative and ERBB2-positive (IRR, 1.46; 95% CI, 1.38-1.54; P < .001), and TNBC (IRR, 2.07; 95% CI, 2.01-2.14; P < .001) subtypes were higher than those in non-Hispanic White patients, but the incidence of the HR-positive and ERBB2-negative subtype in Black women was lower (IRR, 0.86; 95% CI, 0.84-0.87; P < .001). The incidences of histological grade 1 (IRR, 0.75; 95% CI, 0.73-0.78; P < .001) and grade 2 (IRR, 0.91; 95% CI, 0.89-0.93; P < .001) were lower in Asian/Pacific Islander vs non-Hispanic White patients. Non-Hispanic White patients had a higher proportion of lobular carcinoma (9.7% [n = 15 718]) and tubular adenocarcinoma (0.6% [n = 997]) than Black (7.2% [n = 1933]; 0.3% [n = 81]), Asian/Pacific Islander (5.7% [n = 1202]; 0.3% [n = 55]), Hispanic White (7.2% [n = 1985]; 0.3% [n = 88]), and American Indian/Alaskan Native patients (7.2% [n = 101]; 0.4% [n = 5]). Conclusions and Relevance: This cohort study found notable disparities in incidences and proportions of different molecular subtypes, histological grades, pathological patterns, T stages, TNM stages, and tumor sites associated with race/ethnicity. The findings suggest that combining epidemiologic with genomic and molecular profiling data warrants further research.


Assuntos
Neoplasias da Mama/classificação , Neoplasias da Mama/epidemiologia , Etnicidade/estatística & dados numéricos , Grupos Raciais/estatística & dados numéricos , Programa de SEER , Estudos de Coortes , Detecção Precoce de Câncer/estatística & dados numéricos , Feminino , Humanos , Incidência , Estadiamento de Neoplasias , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Estados Unidos
17.
J Hazard Mater ; 393: 122324, 2020 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-32135361

RESUMO

Photocatalytic CO2 reforming is considered to be an effective method for clean, low-cost, and environmentally friendly reduction and conversion of CO2 into hydrocarbon fuels by utilizing solar energy. However, the low separation efficiency of charge carriers and deficient reactive sites have severely hampered the efficiency of the photocatalytic CO2 reforming process. Therefore, cocatalysts are usually loaded onto the surface of semiconductor photocatalysts to reduce the recombination of charge carriers and accelerate the rates of surface reactions. Herein, molybdenum (Mo) nanospheres are proposed as a novel non-precious cocatalyst to enhance the photocatalytic CO2 reforming of g-C3N4 significantly. The Mo nanospheres boost the adsorption of CO2 and activate the surface CO2via a photothermal effect. The time-resolved fluorescence decay spectra reveals that the lifetime of photo-induced charge carriers is prolonged by the Mo nanospheres, which guarantees the migration of charge carriers from g-C3N4 to Mo nanospheres. Unexpectedly, Mo loaded g-C3N4 can effectively utilize a wide spectral range from UV to near-infrared region (NIR, up to 800 nm). These findings highlight the potential of Mo nanospheres as a novel cocatalyst for photocatalytic CO2 reforming to CH4.

18.
Nanomaterials (Basel) ; 9(11)2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31671593

RESUMO

Novel fibrous graphitic carbon nitride (g-C3N4) derivatives prepared from metal organic frameworks (MOFs) were doped with Ce3+ (Ce-C3N4) as photocatalytic materials. Ce-C3N4 was characterized using various techniques, revealing its high specific surface area, excellent photocatalytic activity, and stability for H2 evolution under visible light irradiation. The fluorine modified samples show superior photocatalytic activity under visible light irradiation, which is due to the presence of more active sites and enhanced absorption of solar energy. This work provides a new synthetic route for MOF-derived g-C3N4 that can be doped with different metal ions. The fluorine modified Ce-C3N4 is an efficient photocatalyst with potential for many applications related to energy and the environment.

19.
ACS Omega ; 4(13): 15593-15599, 2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31572860

RESUMO

Oxygen vacancy-modified WO3-x nanorods composited with g-C3N4 have been synthesized via the chemisorption method. The crystalline structure, morphology, composition, band structure, and charge separation mechanism for WO3-x /g-C3N4 heterostructures are studied in detail. The g-C3N4 nanosheets are attached on the surface of WO3-x nanorods. The Z-scheme separation is confirmed by the analysis of generated hydroxyl radicals. The electrons in the lowest unoccupied molecular orbital of g-C3N4 and the holes in the valence band of WO3 can participate in the photocatalytic reaction to reduce CO2 into CO. New energy levels of oxygen vacancies are formed in the band gap of WO3, further extending the visible-light response, separating the charge carriers in Z-scheme and prolonging the lifetime of electrons. Therefore, the WO3-x /g-C3N4 heterostructures exhibit much higher photocatalytic activity than the pristine g-C3N4.

20.
Dalton Trans ; 48(2): 426-434, 2019 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-30403237

RESUMO

Surface-enhanced Raman scattering (SERS) and surface-enhanced infrared absorption (SEIRA) are complementary techniques, and both provide fingerprint structural information on various materials with a high sensitivity. Herein, Zn-Al layered double hydroxides (LDHs) are proposed for the first time as highly sensitive and uniform substrates for both SERS and SEIRA. Zn-Al LDHs show a remarkable SERS effect with an enhancement factor (EF) as high as 1.637 × 104 by using 4-mercaptobenzoic acid (4-MBA) as the probe molecule, where the charge transfer and hydrogen bonds are believed to result in the SERS effect. Interestingly, Zn-Al LDHs also exhibit SEIRA by using 4-methoxybenzenethiol (4-MTP), where the resultant substrates possess excellent long-term stability. This study not only presents a facile route to fabricate LDH materials, but also provides a novel substrate that can be used in both SERS and SEIRA.

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