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1.
Sensors (Basel) ; 24(4)2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38400380

RESUMO

As a fundamental issue in robotics academia and industry, indoor autonomous mobile robots (AMRs) have been extensively studied. For AMRs, it is crucial to obtain information about their working environment and themselves, which can be realized through sensors and the extraction of corresponding information from the measurements of these sensors. The application of sensing technologies can enable mobile robots to perform localization, mapping, target or obstacle recognition, and motion tasks, etc. This paper reviews sensing technologies for autonomous mobile robots in indoor scenes. The benefits and potential problems of using a single sensor in application are analyzed and compared, and the basic principles and popular algorithms used in processing these sensor data are introduced. In addition, some mainstream technologies of multi-sensor fusion are introduced. Finally, this paper discusses the future development trends in the sensing technology for autonomous mobile robots in indoor scenes, as well as the challenges in the practical application environments.

2.
J Surg Oncol ; 128(4): 612-627, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37178368

RESUMO

BACKGROUND AND OBJECTIVES: Negative surgical margins are significant in improving patient outcomes. However, surgeons can only rely on visual and tactile information to identify tumor margins intraoperatively. We hypothesized that intraoperative fluorescence imaging with indocyanine green (ICG) could serve as an assistive technology to evaluate surgical margins and guide surgery in bone and soft tissue tumor surgery. METHODS: Seventy patients with bone and soft tissue tumors were enrolled in this prospective, non-randomized, single-arm feasibility study. All patients received intravenous indocyanine green (0.5 mg/kg) before surgery. Near-infrared (NIR) imaging was performed on in situ tumors, wounds, and ex vivo specimens. RESULTS: 60/70 tumors were fluorescent at NIR imaging. The final surgical margins were positive in 2/55 cases, including 1/40 of the sarcomas. Surgical decisions were changed in 19 cases by NIR imaging, and in 7/19 cases final pathology demonstrated margins were improved. Fluorescence analysis showed that the tumor-to-background ratio (TBR) of primary malignant tumors was higher than that of benign, borderline, metastatic, and tumors ≥5 cm in size had higher TBR than those <5 cm. CONCLUSIONS: ICG fluorescence imaging may be a beneficial technique to assist in surgical decision making and improving surgical margins in bone and soft tissue tumor surgery.


Assuntos
Verde de Indocianina , Neoplasias de Tecidos Moles , Humanos , Margens de Excisão , Estudos Prospectivos , Imagem Óptica/métodos , Neoplasias de Tecidos Moles/diagnóstico por imagem , Neoplasias de Tecidos Moles/cirurgia , Tomada de Decisões
3.
Entropy (Basel) ; 25(1)2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36673168

RESUMO

Nonholonomic four-wheeled mobile robot (NFMR) is a typical multiple input-multiple output system that formulates its kinematic dynamics concerning position and attitude in a parallel manner. However, due to the lumped disturbances and interconnected states, demand-satisfied performance is difficult to obtain for existing coupled control solutions. To address this problem, a double-loop sliding-mode control (DLSMC) mechanism is proposed for achieving position/attitude cascade regulation. For the outer position tracking loop in the proposed scheme, a sliding mode control method of the bounded time-varying integral nonsingular terminal is designed to guarantee fast tracking in the presence of large initial errors and input saturation. On the other hand, for the inner attitude control loop, a novel adaptive barrier function-based sliding-mode control method is proposed without control gain overestimation. This enables the attitude to follow within a predefined vicinity of the sliding mode surface and holds it subsequently independent of the lumped uncertainties. Theoretical analysis is conducted to demonstrate the asymptotic stability. Comparative experiments implemented on a homemade NFMR show enhanced trajectory tracking performance and system robustness using position/attitude cascade regulation via the proposed DLSMC mechanism.

4.
Cancer Cell Int ; 21(1): 227, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33879126

RESUMO

OBJECTIVE: The purpose of this study is to explore the effect of miRNA-539 on osteosarcoma (OS) and the underlying mechanism, so as to find a new method for early diagnosis and treatment of osteosarcoma. METHOD: miRNA-539 mimics was transfected into osteosarcoma cells 143b and MG-63 and upregulated the expression of miR-539. QT-PCR was used to detect transfection efficacy. CCK-8 method was used to detect proliferation of 143b and MG-63 osteosarcoma cells and flow cytometry was used to detect the apoptosis of osteosarcoma cells 143b and MG-63. Wound-healing test and Transwell test were used to detect the migration and invasion ability of osteosarcoma cells. TRIAP1 was found to be the potential target gene of miRNA-539 by online bioinformatics software and the expression level of TRIAP1 in osteosarcoma cells overexpressing miRNA-539 was detected by qT-PCR. Western blot was used to detect the level of expression of TRIAP1 and its downstream genes (p53, p21, apaf1 and caspase9) in osteosarcoma cells 143b and MG63 transfected with miR-539 mimics or miR-539 mimics-NC. A model of osteosarcoma subcutaneously transplanted in nude mice was constructed to observe the effect of miRNA-539 on the growth rate of osteosarcoma in vivo. RESULTS: After transfection of miRNA-539 mimics in osteosarcoma cells 143b and MG63, the proliferation level, migration ability, and invasion ability of the osteosarcoma cells were significantly lower than that in the control group, and the apoptosis level was significantly higher than that in the control group (P < 0.01). The dual luciferase reporter confirmed that TRIAP1 was the target of miR-539, and the expression level of TRIAP1 in 143b and MG63 transfected with miRNA-539 mimics was proved to be significantly lower than that in the control group (P < 0.01).The western blot showed the expression of genes targeted by TRIAP1 was upregulated when the expression of TRIAP1 was downregulated. In vivo, the osteosarcoma growth rate in the miRNA-539 mimics group was significantly slower than that in the control group (P < 0.01). CONCLUSIONS: MiRNA-539 may inhibit the cell proliferation, migration and invasion of osteosarcoma cells and promote the apoptosis of osteosarcoma cells by targeting on TRIAP1.

5.
Cancer Cell Int ; 21(1): 187, 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33789678

RESUMO

BACKGROUND: Myeloma bone disease (MBD) is a severe complication of multiple myeloma (MM) mainly due to an imbalance between enhanced osteoclast activity and reduced osteoblast function. Previous studies have demonstrated that miRNAs play a vital role in the osteogenic differentiation of mesenchymal stromal cells (MSCs) in MM. However, the value of miR­302b in MBD remains to be further elucidated. The aim of this study is to explore the role of miR­302b in the regulation of MBD osteogenic differentiation and evaluate the potential of a new therapeutic strategy for the clinical treatment of MBD. METHOD: Our previous research demonstrated that MiR-302b belongs to the miR-302 cluster and is able to inhibit tumor growth and osteolysis in an orthotopic osteosarcoma xenograft tumor mouse model. In this study, we first transfected miR-302b mimics, miR-302b inhibitor, and miR-302b NC into MM1.S and RPMI8226 MM cells to detect the correlation between miR-302b expression in the pathological specimens and the clinicopathological features by qPCR, the target correlation between miR-302b and DKK1 by immunohistochemistry, qPCR and Western blot, and the correlation between miR-302b and the Wnt/ß-catenin signaling pathway by Western blot. The effect of miR-302b on osteoblastogenesis was also studied in a subperiosteal tumorigenesis model of NOD/SCID nude mice. RESULTS: We found that increased miR-302b suppressed cell proliferation and induced cell apoptosis in RPMI 8226 and MM1.S cells. TargetScan online bioinformatic analysis predicted that miR-302b is able to bind to 3'UTR of DKK1 mRNA. Target binding of miR-302b to DKK1 was demonstrated by dual-luciferase reporter assay, qPCR, Western blot and immunohistochemistry, indicating that miR-302b is able to degrade DKK1 in RPMI 8226 and MM1.S cells. The model of co-culturing MM cells with preosteoblast MC3T3-E1 cells showed that miR-302b inhibits MM-induced suppression of osteoblast differentiation. Western blotting showed that miR-302b promotes the Wnt/ß-catenin signaling pathway in MM cells. Micro-CT and immunohistochemistry results showed that miR-302b suppresses myeloma bone destruction in vivo. CONCLUSION: miR-302b is able to target DKK1 and promote the Wnt/ß-catenin signaling pathway in MM.

6.
Med Sci Monit ; 27: e928617, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33481770

RESUMO

BACKGROUND Our objective was to explore a synthetic alginate hydrogel delivery system for the delivery of demineralized bone matrix (DBM) particles for bone graft substitutes. MATERIAL AND METHODS The physiochemical properties of surface morphology, porosity measurements, in vitro degradation, equilibrium swelling, and mechanical testing of combined DBM powder and alginate in amounts of 0 mg/1 mL, 25 mg/1 mL, 50 mg/1 mL, and 100 mg/1 mL were detected. In vitro cell culture and in vivo studies using Sprague-Dawley rats were performed to evaluate the biocompatibility and osteoinductivity of DBM-alginate (ADBM) composites. RESULTS DBM particles were uniformly scattered in all composites, and macro-scale pores were omnipresent. All composites showed a similar low degradation rate, with approximately 85% of weight remaining after 15 days. As the concentration of DBM particles in composites increased, degradation in collagenase and elastic modulus increased and the pore area and swelling ratio significantly decreased. No cytotoxicity of ADBM or alginate on mesenchymal stem cells (MSCs) was observed. Cell cultivation with ADBM showed greater osteogenic potential, evidenced by the upregulation of alkaline phosphatase and alizarin red staining activity and the mRNA expression level of marker genes RUNX2, OCN, OPN, and collagen I compared with the cells grown in alginate. Evaluation of ectopic bone formation revealed the osteoinductivity of the ADBM composites was significantly greater than that of DBM particles. Osteoinduction of the composites was demonstrated by a cranial defect model study. CONCLUSIONS The delivery of DBM particles using a synthetic alginate hydrogel carrier may be a promising approach in bone tissue engineering for bone defects.


Assuntos
Alginatos/química , Matriz Óssea/transplante , Substitutos Ósseos/química , Hidrogéis/química , Engenharia Tecidual/métodos , Animais , Matriz Óssea/química , Modelos Animais de Doenças , Masculino , Ratos , Ratos Sprague-Dawley
7.
Pharmazie ; 76(6): 244-248, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34078517

RESUMO

This study aimed to investigate the effect of metformin on osteoclast differentiation and apoptosis. Low concentration of metformin inhibited osteoclast differentiation and downregulated the expression of TRAP, RANK, Cathepsink, NFATC-1, MMP-9 and TRAF-6. High concentration of metformin promoted osteoclast apoptosis and upregulated the expression of Bax/Bcl-2 and caspase-3; BV/TV, BS/TV, Tb.N and BMD were increased while Tp.Sp decreased in the group of intraperitoneal metformin+femoral intramedullary osteoclast injection (Met+OC) compared with the control group, 1 nM metformin downregulated Akt, p44/42 MAPK, JNK, p38 MAPK phosphorylation, 5 nM metformin down regulated ERK and Akt phosphorylation. These results suggest that a low concentration of metformin inhibits osteoclast differentiation through PI3K/Akt and MAPK/ERK signaling pathway; high concentrations of metformin promote osteoclast apoptosis through PI3K/Akt and ERK signaling pathway.


Assuntos
Metformina , Osteoclastos , Apoptose , Diferenciação Celular , Metformina/farmacologia , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt
8.
Eur Spine J ; 29(5): 1147-1158, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32200495

RESUMO

PURPOSE: To evaluate the safety and efficacy of a system aiming to correct scoliosis called "electromagnetically controlled shape-memory alloy rods" (EC-SMAR) used in a rabbit model. METHODS: We heat-treated shape-memory alloy (SMA) rods to achieve a transition temperature between 34 and 47 °C and a C-shape austenite phase. We then developed a water-cooled generator capable of generating an alternating magnetic field (100 kHz) for induction heating. We next studied the efficacy of this system in vitro and determined some parameters prior to proceeding with animal experiments. We then employed a rabbit model, in which we fixed a straight rod along the spinous processes intraoperatively, and conducted induction heating postoperatively every 4 days for 1 month, while performing periodic X-ray assessments. RESULTS: Significant kyphotic deformations with Cobb angles of about 45° (p < 0.01) were created in five rabbits, and no complications occurred throughout the experiment. The rabbits are still very much alive and do not show any signs of discomfort. CONCLUSIONS: This is the first system that can modulate spinal deformation in a gradual, contactless, noninvasive manner through electromagnetic induction heating applied to SMA alloy rods. Although this study dealt with healthy spines, it provides promising evidence that this device also has the capacity to correct human kyphosis and even scoliosis in the future. These slides can be retrieved under Electronic Supplementary Material.


Assuntos
Escoliose , Ligas de Memória da Forma , Ligas , Animais , Níquel , Coelhos , Escoliose/cirurgia , Coluna Vertebral , Titânio
9.
Sensors (Basel) ; 20(18)2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32937859

RESUMO

Due to the praiseworthy maneuverability and actuation flexibility, the in-wheel-motor-driven mobile robots (IWMD-MR) are widely employed in various industrial fields. However, the active estimation and rejection of unknown disturbances/uncertainties remain a tough work for formulating a stable lateral motion controller. To address the challenge, this paper proposes a robust lateral stabilization control (RLSC) scheme for the developed IWMD-MR by designing an active disturbance suppression mechanism. The distinctive features of the proposed RLSC method are threefold: (i) With a fuzzy estimator, a modified super-twisting sliding mode method is designed to eliminate the system perturbations and time-varying lumped disturbances in an active manner; (ii) The resultant system trajectory is forced into a bounded switching region within finite time, which can be maintained therein for subsequent periods; (iii) Employing the Lyapunov function, new adaption rules for multivariable gains are derived to preserve the lateral motion stability and robustness. Finally, under the direct yaw moment control framework, simulation experiments of real-life IWMD-MR are offered to verify the effectiveness of the presented RLSC method.

10.
J Cell Biochem ; 120(8): 13121-13132, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30887562

RESUMO

Osteoporosis (OP) results from the impaired function of endogenous bone marrow mesenchymal stem cells (BMSCs). Icariin (ICA) has shown potential osteoprotective effects. However, the molecular mechanism for the anabolic action of ICA remains largely unknown. The objective of the present study is to investigate whether ICA prevents bone loss by acting on BMSCs via affecting the level of autophagy after ovariectomy (OVX). The BMSCs were extracted from BALB/c mice treated with ICA, chloroquine (CQ, an autophagy inhibitor) or ICA + CQ. The OVX mice were injected with ICA, CQ, or ICA + CQ for 1 month. We performed Alizarin Red staining and alkaline phosphatase staining to detect osteogenic differentiation of BMSCs. Micro-CT, hematoxylin and eosin staining, Oil Red O staining, and tartrate-resistant acid phosphatase staining were used to assess the bone mass, lipid droplets and osteoclasts in femurs. Autophagy activity in BMSCs from different groups was evaluated by Western blot analysis. The osteogenic differentiation of BMSCs from OVX-induced OP mice was decreased. Treatment with ICA reduced bone loss and formation of osteoclasts and increased osteogenic differentiation of BMSCs in vitro and vivo. In addition, autophagy was enhanced in BMSCs of OVX mice treated with ICA. Our results indicate that ICA prevents OVX-induced bone loss possibly by strengthening the osteogenic differentiation of BMSCs via increasing autophagic activity.


Assuntos
Autofagia/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Flavonoides/uso terapêutico , Osteogênese/efeitos dos fármacos , Animais , Cloroquina/uso terapêutico , Feminino , Citometria de Fluxo , Imunofluorescência , Camundongos , Camundongos Endogâmicos BALB C , Osteoporose/metabolismo , Osteoporose/prevenção & controle , Ovariectomia
11.
Med Sci Monit ; 25: 1362-1372, 2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30785872

RESUMO

BACKGROUND Osteoblastoma is a rare, benign, osteolytic neoplasm commonly found in the spine in early adulthood. Here, we review the clinical characteristics, radiographic findings, and surgical management of patients with spinal osteoblastoma. MATERIAL AND METHODS Thirteen patients with osteoblastoma who underwent surgery at our institute from June 2008 to November 2017 were enrolled in this study. The American Spinal Injury Association (ASIA) impairment scale was used to assess neurological function. All patients were treated with either total excision or intralesional piecemeal excision without postoperative radiotherapy. Clinical efficacy was evaluated by visual analog scale (VAS) scores, the Oswestry Disability Index (ODI) of nerve function, physical and radiographic examinations, bone fusion, and neurologic status. RESULTS The follow-up lasted 23-82 months (average, 43.8 months). The average surgical time was 178.1 minutes (range, 100-230 minutes), with an average intraoperative blood loss of 574 mL (range, 230-1100 mL). Postoperatively, VAS scores decreased from 6.2±1.7 to 0.5±0.7 (P<0.001). The preoperative and final ODI scores were 51.1±7.7 and 22.6±4.9, respectively, reflecting a significant decrease (P<0.001). According to the ASIA classification, 3 patients had grade C, 3 patients had grade D, and 7 patients had grade E disease. Three months postoperatively, 1 patient had grade D and 10 patients had grade E disease; ultimately, all cases were grade E disease. Only 1 patient experienced local recurrence and underwent en bloc marginal resection with postoperative radiotherapy. All patients remained neurologically stable without any major complications. CONCLUSIONS Accurate intraoperative localization with complete resection is the key to preventing recurrence. Aggressive surgical resection can achieve satisfactory clinical and radiographic outcomes.


Assuntos
Osteoblastoma/diagnóstico , Osteoblastoma/terapia , Adolescente , Adulto , Idoso , Neoplasias Ósseas/cirurgia , Criança , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/cirurgia , Procedimentos de Cirurgia Plástica , Estudos Retrospectivos , Coluna Vertebral/cirurgia , Resultado do Tratamento
12.
Sensors (Basel) ; 19(15)2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31362439

RESUMO

In real-world robotic navigation, some ambiguous environments contain symmetrical or featureless areas that may cause the perceptual aliasing of external sensors. As a result of that, the uncorrected localization errors will accumulate during the localization process, which imposes difficulties to locate a robot in such a situation. Using the ambiguity grid map (AGM), we address this problem by proposing a novel probabilistic localization method, referred to as AGM-based adaptive Monte Carlo localization. AGM has the capacity of evaluating the environmental ambiguity with average ambiguity error and estimating the possible localization error at a given pose. Benefiting from the constructed AGM, our localization method is derived from an improved Dynamic Bayes network to reason about the robot's pose as well as the accumulated localization error. Moreover, a portal motion model is presented to achieve more reliable pose prediction without time-consuming implementation, and thus the accumulated localization error can be corrected immediately when the robot moving through an ambiguous area. Simulation and real-world experiments demonstrate that the proposed method improves localization reliability while maintains efficiency in ambiguous environments.

13.
Med Sci Monit ; 21: 638-45, 2015 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-25725252

RESUMO

BACKGROUND: The expression of Src and phospho-Src (p-Src) is closely related to tumor invasion and metastasis. The aim of the present study was to investigate the expression of these molecules in osteosarcoma and their relationship with each other, to provide a theoretical basis to understand the prognosis of osteosarcoma. MATERIAL AND METHODS: We selected surgically resected osteosarcoma specimens from 116 patients of Zhongnan Hospital of Wuhan University and Hubei Cancer Hospital, Hubei, China, between January 2000 and January 2010 with detailed follow-up data. Twenty osteochondroma specimens from the corresponding period were used as controls. Expression of Src and p-Src was detected in osteosarcoma and osteochondroma by immunohistochemistry. We analyzed the relationship of the 2 proteins and osteosarcoma patient prognosis. RESULTS: The expression of Src and p-Src in osteosarcoma was significantly higher than the expression level in osteochondroma (P<0.05). The expression levels of the 2 proteins, clinical stage, and tumor metastasis were significantly associated with survival time (P<0.05), but there was no correlation between age or sex and survival time. The expression of Src and p-Src in osteosarcoma was positively correlated. CONCLUSIONS: Src and p-Src can be used as an auxiliary indicator to determine a malignant phenotype of bone tumors, and the combined detection of Src and p-Src may indicate the prognosis of osteosarcoma.


Assuntos
Osteossarcoma/metabolismo , Osteossarcoma/patologia , Proteínas Proto-Oncogênicas pp60(c-src)/metabolismo , Adolescente , Adulto , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Neoplasias Ósseas/cirurgia , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Osteocondroma/metabolismo , Osteocondroma/patologia , Osteocondroma/cirurgia , Osteossarcoma/cirurgia , Fosforilação , Cuidados Pós-Operatórios , Prognóstico , Adulto Jovem
14.
J Foot Ankle Surg ; 54(4): 663-70, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25956019

RESUMO

A meta-analysis was performed to investigate the outcomes between absorbable screw (AS) and metallic screw (MS) fixation for distal tibiofibular syndesmosis injuries (DTSIs). Randomized controlled trials comparing AS versus MS fixation in DTSIs were searched systematically, and the outcomes were analyzed using Review Manager Software, version 5.2. The risk ratio (RR) or mean difference with the 95% confidence interval (CI) was calculated using the fixed effects or random effects model. A total of 16 studies were included in the meta-analysis. No statistically significant difference was found between AS and MS fixation in excellent and good functional recovery rate (RR 1.11, 95% CI 1.00 to 1.23, I(2) = 60%, p = .06), infection (RR 1.66, 95% CI 0.73 to 3.79, I(2) = 0%, p = .23), incidence of pain (RR 0.68, 95% CI 0.24 to 1.92, I(2) = 12%, p = .47), screw broken (RR 0.31, 95% CI 0.03 to 2.93, I(2) = %, p = .31), heterotopic ossification (RR 1.93, 95% CI 0.21 to 17.62, I(2) = 51%, p = .56; 472 cases in 4 studies), fracture healing time (mean difference -1.88, 95% CI -3.51 to -0.26, I(2) = 93%, p = .02,), duration of operation time (mean difference 7.64, 95% CI -3.80 to 19.09, I(2) = 98%, p = .19). The incidence of foreign body reaction was higher with AS fixation (RR 6.07, 95% CI 2.54 to 14.50, I(2) = 0%, p < .001). The reoperation rate was higher with MS fixation (RR 0.08, 95% CI 0.03 to 0.18, I(2) = 77%, p < .01). The functional outcomes of AS were as good as those with MS for DTSIs. Other than the foreign body reaction, the complications occurring after AS fixation were not as serious as those with MS fixation. AS fixation might be a preferable alternative for reconstruction of DTSIs.


Assuntos
Implantes Absorvíveis , Fraturas do Tornozelo/cirurgia , Parafusos Ósseos , Fixação Interna de Fraturas/instrumentação , Metais , Reação a Corpo Estranho/etiologia , Humanos , Complicações Pós-Operatórias
15.
IEEE Trans Neural Netw Learn Syst ; 34(10): 7873-7886, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35157596

RESUMO

This article investigates the consensus control for a class of fractional-order (FO) nonlinear multi-agent systems (MASs). Severe sensor/actuator faults and time-varying delays are both considered in the FO MASs. The severe faults may cause unknown control directions in MASs. A new adaptive controller, which is composed of a distributed FO Nussbaum gain, an FO filter, and an auxiliary function, is presented to deal with the severe faults. To cope with the time-varying delays, two different methods are proposed based on barrier Lyapunov function and Lyapunov-Krasovskii function, respectively. Meanwhile, the radial basis function neural network (RBF NN) is applied to approximate the unknown nonlinear functions during the design procedures. This can result in a low-complexity controller. Finally, two simulation examples are used to verify the validity of the proposed schemes.

16.
Clin Exp Med ; 23(8): 5389-5398, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37861934

RESUMO

Heat shock protein B6 (HSPB6) plays a certain role in the formation of several cancers, whereas its effect on osteosarcoma remains unclear. In this study, the effect of HSPB6 on osteosarcoma was validated through numerous experiments. HSPB6 was down-regulated in osteosarcoma. As indicated by the result of CCK-8 and colony formation assays, HSPB6 overexpression was likely to inhibit the osteosarcoma cells proliferation, whereas the flow cytometry analysis suggested that apoptosis of osteosarcoma cells was increased after HSPB6 overexpression. Furthermore, transwell and wound healing assays suggested that when HSPB6 was overexpressed, osteosarcoma cells migration and invasion were declined. Moreover, the western blotting assay suggested that the protein level of p-ERK1/2 was down-regulated in osteosarcoma when HSPB6 was overexpressed. Besides, the effect of HSPB6 on osteosarcoma in vivo was examined. As indicated by the result, HSPB6 overexpression was likely to prevent osteosarcoma growth and lung metastasis in vivo. As revealed by the findings of this study, HSPB6 overexpression exerted anticancer effects in osteosarcoma through the ERK signaling pathway and HSPB6 may be suitable target for osteosarcoma molecular therapies.


Assuntos
Neoplasias Ósseas , Osteossarcoma , Humanos , Apoptose , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Proteínas de Choque Térmico HSP20/genética , Proteínas de Choque Térmico HSP20/metabolismo , Sistema de Sinalização das MAP Quinases , Osteossarcoma/patologia , Transdução de Sinais
17.
Exp Ther Med ; 26(3): 457, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37614424

RESUMO

As an important 5-methylcytidine (m5C) methyltransferase, NOP2/Sun RNA methyltransferase family member 6 (NSUN6) has been reported to play an important role in the progression of several diseases. However, the role of NSUN6 in the progression of osteosarcoma (OS) remains unclear. This study aimed to identify the role of NSUN6 in the progression of OS and clarify the potential molecular mechanism. The present study discovered that NSUN6 was upregulated in OS and a higher NSUN6 expression was a strong indicator for poorer prognosis of patients with OS. In addition, the loss of NSUN6 led to reduced proliferation, migration and invasion of OS cells. Through bioinformatics analysis, RNA immunoprecipitation (RIP) and methylated RIP assays, eukaryotic elongation factor 1 α-2 (EEF1A2) was identified and validated as a potential target of NSUN6 in OS. Mechanistically, the expression of EEF1A2 was significantly suppressed following NSUN6 knockdown due to reduced EEF1A2 mRNA stability in an m5C-dependent manner. Meanwhile, NSUN6 deficiency inhibited m5C-dependent activation of Akt/mTOR signaling pathway. In addition, genetic overexpression of EEF1A2 or pharmacological activation of the Akt signaling pathway counteracted the suppressive effects of NSUN6 deficiency on the proliferation, invasion and migration of OS cells. The current findings suggested that NSUN6 may serve as a potential therapeutic target for OS treatment.

18.
Cell Death Dis ; 14(2): 125, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36792587

RESUMO

5-methylcytosine (m5C) modification, which is mainly induced by the RNA methyltransferase NSUN2 (NOP2/Sun domain family, member 2), is an important chemical posttranscriptional modification in mRNA and has been proven to play important roles in the progression of many cancers. However, the functions and underlying molecular mechanisms of NSUN2-mediated m5C in osteosarcoma (OS) remain unclear. In this study, we found NSUN2 was highly expressed in OS tissues and cells. We also discovered that higher expression of NSUN2 predicted poorer prognosis of OS patients. Our study showed that NSUN2 could promote the progression of OS cells. Moreover, we employed RNA sequencing, RNA immunoprecipitation (RIP), and methylated RIP to screen and validate the candidate targets of NSUN2 and identified FABP5 as the target. We observed that NSUN2 stabilized FABP5 mRNA by inducing m5C modification and further promoted fatty acid metabolism in OS cells. Moreover, both knocking down the expression of FABP5 and adding fatty acid oxidation inhibitor could counterbalance the promoting effect of NSUN2 on the progression of OS. Our study confirms that NSUN2 can up-regulate the expression of FABP5 by improving the stability of FABP5 mRNA via m5C, so as to promote fatty acid metabolism in OS cells, and finally plays the role in promoting the progression of OS. Our findings suggest that NSUN2 is a promising prognostic marker for OS patients and may serve as a potential therapeutic target for OS treatment. A schematic illustration was proposed to summarize our findings.


Assuntos
Metiltransferases , Osteossarcoma , Humanos , Metilação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Metiltransferases/genética , Metiltransferases/metabolismo , RNA/metabolismo , Osteossarcoma/genética , Ácidos Graxos , Proteínas de Ligação a Ácido Graxo/genética , Proteínas de Ligação a Ácido Graxo/metabolismo
19.
Nanoscale Adv ; 5(18): 5102-5114, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37705764

RESUMO

Skin wounds caused by external injuries remain a serious challenge in clinical practice. Wound dressings that are antibacterial, pro-angiogenic, and have potent regeneration capacities are highly desirable for wound healing. In this study, a minimally invasive and wound-friendly Cu@ZIF-8 encapsulated PEGDA/CMCS microneedle (MN) array was fabricated using the molding method to promote wound healing. The MNs had good biocompatibility, excellent mechanical strength, as well as strong antibacterial properties and pro-angiogenic effects. When incubated with H2O2, Cu@ZIF-8 nanoparticles generated reactive oxygen species, which contributed to their antibacterial properties. Due to the oxidative stress of the cupric ions released from Cu@ZIF-8 and the anti-bacterial capability of the PEGDA/CMCS hydrogel scaffold, such an MN array presents excellent antibacterial activity. Moreover, with the continuous release of Cu ions from the scaffold, such MNs are effective in terms of promoting angiogenesis. With considerable biocompatibility and a minimally invasive approach, the degradable MN array composed of PEGDA/CMCS possessed superior capabilities to continuously and steadily release the loaded ingredients and avoid secondary damage to the wound. Benefiting from these features, the Cu@ZIF-8 encapsulated degradable MN array can dramatically accelerate epithelial regeneration and neovascularization. These results indicated that the combination of Cu@ZIF-8 and degradable MN arrays is valuable in promoting wound healing, which opened a new window for treatment of skin defection.

20.
Cancers (Basel) ; 15(8)2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37190330

RESUMO

(1) Background: Biopsies are the gold standard for the diagnosis of musculoskeletal tumors. In this study, we aimed to explore whether indocyanine green near-infrared fluorescence imaging can assist in the biopsy of bone and soft tissue tumors and improve the success rate of biopsy. (2) Method: We recruited patients with clinically considered bone and soft tissue tumors and planned biopsies. In the test group, indocyanine green (0.3 mg/kg) was injected. After identifying the lesion, a near-infrared fluorescence camera system was used to verify the ex vivo specimens of the biopsy in real time. If the biopsy specimens were not developed, we assumed that we failed to acquire lesions, so the needle track and needle position were adjusted for the supplementary biopsy, and then real-time imaging was performed again. Finally, we conducted a pathological examination. In the control group, normal biopsy was performed. (3) Results: The total diagnosis rate of musculoskeletal tumors in the test group was 94.92% (56/59) and that in the control group was 82.36% (42/51). In the test group, 14 cases were not developed, as seen from real-time fluorescence in the core biopsy, and then underwent the supplementary biopsy after changing the puncture direction and the location of the needle channel immediately, of which 7 cases showed new fluorescence. (4) Conclusions: Using the near-infrared fluorescence real-time development technique to assist the biopsy of musculoskeletal tumors may improve the accuracy of core biopsy and help to avoid missed diagnoses, especially for some selected tumors.

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