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1.
Exp Cell Res ; 440(2): 114134, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38901790

RESUMEN

Individuals with type 2 diabetes mellitus frequently display heightened levels of palmitic acid (PA) in their serum, which may lead to ß-cell damage. The involvement of ferroptosis, a form of oxidative cell death in lipotoxic ß-cell injury remains uncertain. Here, we have shown that PA induces intracellular lipid peroxidation, increases intracellular Fe2+ content and decreases intracellular glutathione peroxidase 4 (GPX4) expression. Furthermore, PA causes distinct changes in pancreatic islets and INS-1 cells, such as mitochondrial atrophy and increased membrane density. Furthermore, the presence of the ferroptosis inhibitor has a significant mitigating effect on PA-induced ß-cell damage. Mechanistically, PA increased ceramide content and c-Jun N-terminal kinase (JNK) phosphorylation. The ceramide synthase inhibitor effectively attenuated PA-induced ß-cell damage and GPX4/Fe2+ abnormalities, while inhibiting JNK phosphorylation. Additionally, the JNK inhibitor SP600125 improved PA-induced cell damage. In conclusion, by promoting ceramide synthesis, PA inhibited GPX4 expression and increased intracellular Fe2+ to induce ß-cell ferroptosis. Moreover, JNK may be a downstream mechanism of ceramide-triggered lipotoxic ferroptosis in ß-cells.


Asunto(s)
Ceramidas , Ferroptosis , Células Secretoras de Insulina , Ácido Palmítico , Transducción de Señal , Ferroptosis/efectos de los fármacos , Células Secretoras de Insulina/efectos de los fármacos , Células Secretoras de Insulina/metabolismo , Ceramidas/metabolismo , Ácido Palmítico/farmacología , Animales , Transducción de Señal/efectos de los fármacos , Fosfolípido Hidroperóxido Glutatión Peroxidasa/metabolismo , Ratas , Peroxidación de Lípido/efectos de los fármacos , Fosforilación/efectos de los fármacos , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Hierro/metabolismo
2.
RNA Biol ; 18(12): 2247-2260, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-33904383

RESUMEN

MicroRNAs (miRNAs) are associated with healing or deteriorating degenerated intervertebral disc (IVD) tissues in spinal cord diseases, including intervertebral disc degeneration (IDD). IDD represents a chronic process of extracellular matrix destruction, but the relevant molecular mechanisms implicated in the regenerative effects of miRNAs are unclear. Here, we investigated the regenerative effects of microRNA-140 (miR-140-3p) in an IDD model induced by annulus needle puncture. Bioinformatics analysis was conducted to identify regulatory factors (KLF5/N-cadherin/MDM2/Slug) linked to miR-140-3p effects in IDD. Mesenchymal stem cells (MSCs) were extracted from degenerated IVD nucleus pulposus (NP), and the expression of miR-140-3p/KLF5/N-cadherin/MDM2/Slug was manipulated to explore their effects on cell proliferation, migration, apoptosis and differentiation. The results showed that miR-140-3p was under-expressed in the degenerated IVD NP, whereas its overexpression alleviated IDD. Mechanistic studies suggested that miR-140-3p targeted KLF5 expression, and high KLF5 expression impeded the migration and differentiation of MSCs. In degenerated IVD NP-derived MSCs, MiR-140-3p-mediated KLF5 downregulation simultaneously elevated N-cadherin expression and transcriptionally inhibited MDM2, thus upregulating Slug expression. The experimental data indicated that miR-140-3p enhanced the proliferation, migration and differentiation of degenerated IVD NP-derived MSCs and repressed their apoptosis. The in vivo validation experiment also demonstrated that miR-140-3p inhibited IDD by modulating the KLF5/N-cadherin/MDM2/Slug axis. Collectively, our results uncovered the regenerative role of miR-140-3p in IDD via regulation of the KLF5/N-cadherin/MDM2/Slug axis, which could be a potential therapeutic target for IDD.Abbreviations: miR-140-3p: microRNA-140-3p; IDD: intervertebral disc degeneration; MSCs: Mesenchymal stem cells; IVD: intervertebral disc; MSCs: mesenchymal stem cells; KLF5: Kruppel-like factor 5; MDM2: mouse double minute 2; NC: negative control; DHI: disc height index.


Asunto(s)
Biología Computacional/métodos , Regulación hacia Abajo , Degeneración del Disco Intervertebral/genética , Células Madre Mesenquimatosas/citología , MicroARNs/genética , Regiones no Traducidas 3' , Animales , Cadherinas/genética , Movimiento Celular , Proliferación Celular , Células Cultivadas , Modelos Animales de Enfermedad , Humanos , Degeneración del Disco Intervertebral/etiología , Factores de Transcripción de Tipo Kruppel/genética , Masculino , Células Madre Mesenquimatosas/química , Proteínas del Tejido Nervioso/genética , Núcleo Pulposo/química , Núcleo Pulposo/citología , Proteínas Proto-Oncogénicas c-mdm2/genética , Ratas , Transducción de Señal , Factores de Transcripción de la Familia Snail/genética
3.
Bioorg Chem ; 94: 103390, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31662212

RESUMEN

Based on the approach of merged pharmacophores of GPR119 agonists and DPP-4 inhibitors, a series of tetrahydropyridopyrimidine compounds were designed as dual GPR119 and DPP-4 modulators with hypoglycemic activity. Seven fragments extracted from DPP-4 inhibitors were hybridized with the scaffold of tetrahydropyridopyrimidine. Among them, compound 51 displayed most potent GPR119 agonistic activity (EC50 = 8.7 nM) and good inhibition rate of 74.5% against DPP-4 at 10 µM. Furthermore, the blood glucose AUC0-2h of 51 was reduced to 19.5% in the oral glucose tolerance test (oGTT) at the dose of 30 mg/kg in C57BL/6N mice, which was more potent than that of vildagliptin (16.4%) at the same dose. The docking study of compound 51 with DPP-4 indicated GPR119 agonists could inhibit DPP-4 to serve as dual GPR119 and DPP-4 modulators.


Asunto(s)
Dipeptidil Peptidasa 4/metabolismo , Inhibidores de la Dipeptidil-Peptidasa IV/farmacología , Hipoglucemiantes/farmacología , Pirimidinas/farmacología , Pirrolidinas/farmacología , Receptores Acoplados a Proteínas G/agonistas , Animales , Glucemia/efectos de los fármacos , Células CHO , Cricetulus , Inhibidores de la Dipeptidil-Peptidasa IV/síntesis química , Inhibidores de la Dipeptidil-Peptidasa IV/química , Relación Dosis-Respuesta a Droga , Diseño de Fármacos , Prueba de Tolerancia a la Glucosa , Humanos , Hipoglucemiantes/síntesis química , Hipoglucemiantes/química , Ratones , Ratones Endogámicos C57BL , Estructura Molecular , Pirimidinas/síntesis química , Pirimidinas/química , Pirrolidinas/síntesis química , Pirrolidinas/química , Receptores Acoplados a Proteínas G/metabolismo , Relación Estructura-Actividad
4.
J Enzyme Inhib Med Chem ; 35(1): 50-58, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31656107

RESUMEN

GPR119 is a promising target for discovery of anti-type 2 diabetes mellitus agents. We described the optimisation of a novel series of pyrimido[5,4-b][1,4]oxazine derivatives as GPR119 agonists. Most designed compounds exhibited good agonistic activities. Among them, compound 10 and 15 demonstrated the potent EC50 values (13 and 12 nM, respectively) and strong inherent activities. Moreover, significant hypoglycaemic effect of compound 15 was observed by reducing the blood glucose AUC0-2h at the dose of 30 mg/kg, which is stronger than Vildagliptin (23.4% reduction vs. 17.9% reduction).


Asunto(s)
Hipoglucemiantes/farmacología , Oxazinas/farmacología , Pirimidinas/farmacología , Receptores Acoplados a Proteínas G/agonistas , Animales , Glucemia/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Prueba de Tolerancia a la Glucosa , Humanos , Hipoglucemiantes/síntesis química , Hipoglucemiantes/química , Ratones , Ratones Endogámicos C57BL , Estructura Molecular , Oxazinas/síntesis química , Oxazinas/química , Pirimidinas/síntesis química , Pirimidinas/química , Relación Estructura-Actividad
5.
Bioorg Chem ; 86: 103-111, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30685641

RESUMEN

A novel series of fused pyrimidine derivatives were designed, synthesized and evaluated as GPR119 agonists. Among them, cyclohexene fused compounds (tetrahydroquinazolines) showed greater GPR119 agonistic activities than did dihydrocyclopentapyrimidine and tetrahydropyridopyrimidine scaffolds. Analogues (16, 19, 26, 28, 42) bearing endo-N-Boc-nortropane amine and fluoro-substituted aniline exhibited better EC50 values (0.27-1.2 µM) though they appeared to be partial agonists.


Asunto(s)
Antihipertensivos/farmacología , Glucemia/efectos de los fármacos , Pirimidinas/farmacología , Receptores Acoplados a Proteínas G/agonistas , Animales , Antihipertensivos/síntesis química , Antihipertensivos/química , Células CHO , Cricetulus , Relación Dosis-Respuesta a Droga , Prueba de Tolerancia a la Glucosa , Humanos , Ratones , Ratones Endogámicos C57BL , Estructura Molecular , Pirimidinas/síntesis química , Pirimidinas/química , Relación Estructura-Actividad
6.
Mol Cell Biochem ; 392(1-2): 109-16, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24771064

RESUMEN

Osteosarcoma is the most bone-associated malignancy with high lethality. The current therapeutic strategy benefits little on the survival of patients. Studies have shown that aberrant activation of Wnt/ß-catenin pathway is essential for the progression of osteosarcoma, implying that targeting this signaling may be an effective way of therapeutics. Recently, TIKI family has been identified as a new class of negative regulators for Wnt/ß-catenin pathway. However, the implication of TIKIs with osteosarcoma has not been explored. Here, we constructed an adenoviral vector that expresses TIKI2 in osteosarcoma cells (Ad-TIKI2). TIKI2 expression was found to be reduced in osteosarcoma specimens and cell lines. In tested osteosarcoma cells, the activation of Wnt/ß-catenin pathway was found to be inhibited by TIKI2 expression. Furthermore, the proliferation, colony formation ability, and invasion were all significantly suppressed in osteosarcoma cells infected with Ad-TIKI2. Finally, animal experiments further confirmed that TIKI2 restoration was able to inhibit the growth of osteosarcoma in vivo. Taken together, we provided evidence that reduced expression of TIKI family protein in osteosarcoma may participate in the progression of osteosarcoma and restoring its expression was able to impair the growth of osteosarcoma.


Asunto(s)
División Celular/fisiología , Metaloendopeptidasas/fisiología , Osteosarcoma/patología , Vía de Señalización Wnt , beta Catenina/metabolismo , Animales , Secuencia de Bases , Línea Celular Tumoral , Proliferación Celular , Cartilla de ADN , Xenoinjertos , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Invasividad Neoplásica , Osteosarcoma/metabolismo , Reacción en Cadena de la Polimerasa
7.
Orthop Surg ; 15(6): 1454-1467, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37186216

RESUMEN

Spinal tuberculosis, also known as Pott's disease or tuberculous spondylitis, is usually secondary to primary infection in the lungs or other systems, and in most instances, is thought to be transmitted via blood. Typical manifestations of infection include narrowing of the intervertebral disc by erosion and bone destruction of adjacent vertebrae. Atypical spinal tuberculosis is a specific type of spinal tuberculosis. It mainly consists of single vertebral lesions, single posterior structure lesions, multiple vertebral lesions, and intra-spinal lesions. Skipped multifocal spinal tuberculosis is one of these types and is characterized by two or more vertebral lesions without the involvement of the adjoining intervertebral discs, regardless of their location. To date, only a few cases have been reported. Upon clinical admission, it can be treated conservatively or surgically, depending on the patient's symptoms. In addition, gene or biological therapies are being investigated. However, because of the exceptional imaging findings and insidious symptoms, it is often misdiagnosed as a neoplastic lesion, osteoporotic fracture, or other infectious spondylitis, increasing the risk of neurological deficit and kyphotic deformity, and delaying the optimal treatment window. In this study, we review the diagnosis and treatment strategies for skipped multifocal spinal tuberculosis lesions and enumerate the common differential diagnoses, to provide reference and guidance for clinical treatment and diagnosis direction.


Asunto(s)
Espondilitis , Tuberculosis de la Columna Vertebral , Humanos , Tuberculosis de la Columna Vertebral/diagnóstico , Tuberculosis de la Columna Vertebral/terapia , Espondilitis/diagnóstico por imagen , Espondilitis/terapia , Diagnóstico Diferencial , Vértebras Torácicas/patología , Imagen por Resonancia Magnética
8.
Acta Biomater ; 158: 475-492, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36640954

RESUMEN

Intervertebral disc degeneration (IVDD) is a degenerative disease characterized by lower-back pain, causing disability globally. Antioxidant therapy is currently considered one of the most promising strategies for IVDD treatment, given the crucial role of reactive oxygen species (ROS) in IVDD pathogenesis. Herein, a ROS-responsive magnesium-containing microsphere (Mg@PLPE MS) was constructed for the antioxidative treatment of IVDD. The Mg@PLPE MS has a core-shell structure comprising poly(lactic-co-glycolic acid) (PLGA) and ROS-responsive polymer poly(PBT-co-EGDM) as the shell and a magnesium microparticle as the core. The poly(PBT-co-EGDM) can be destroyed by H2O2 through the H2O2-triggered hydrophobic-to-hydrophilic transition, subsequently promoting an Mg-water reaction to produce H2. Thus, Mg@PLPE MS provides a valuable platform for H2O2 elimination and controlled H2 release. The generated H2 scavenge for ROS by reacting with noxious •OH. Notably, the Mg@PLPE MS exerted significant antioxidative and anti-inflammatory effects in a disc degeneration rat model and alleviated extracellular matrix degradation and disc cells apoptosis, thereby underlining its efficacy in IVDD treatment. The Mg@PLPE MS also exhibited robust biocompatibility and negligible toxicity, presenting the promise for the antioxidative treatment of IVDD in vivo. STATEMENT OF SIGNIFICANCE: Antioxidant therapy is currently considered one of the most promising strategies for intervertebral disc degeneration (IVDD) treatment, given the crucial role of reactive oxygen species (ROS) in IVDD pathogenesis. Here, ROS-responsive magnesium-containing microspheres (Mg@PLPE MSs) were constructed to alleviate IVDD through controlled release of hydrogen gas. The Mg@PLPE MSs can effectively scavenge overproduced ROS by simultaneously reacting with H2O2 and •OH, thus creating a suitable microenvironment for inhibition of ECM degradation. As a result, Mg@PLPE MSs treated IVDD rats exhibit minimal nucleus pulposus decrease, less extracellular matrix degradation, minimal radial fissure of fibrous rings, and higher disc height index. Therefore, the as-prepared Mg@PLPE MSs may shed a new light on clinical treatment of IVDD.


Asunto(s)
Degeneración del Disco Intervertebral , Disco Intervertebral , Núcleo Pulposo , Ratas , Animales , Degeneración del Disco Intervertebral/patología , Antioxidantes/farmacología , Antioxidantes/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Ratas Sprague-Dawley , Microesferas , Magnesio/metabolismo , Peróxido de Hidrógeno/farmacología , Núcleo Pulposo/patología , Disco Intervertebral/metabolismo
9.
Biochimie ; 214(Pt B): 27-48, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37268183

RESUMEN

Intervertebral disc (IVD) degeneration (IDD) is a common disorder that affects the spine and is a major cause of lower back pain (LBP). The extracellular matrix (ECM) is the structural foundation of the biomechanical properties of IVD, and its degradation is the main pathological characteristic of IDD. Matrix metalloproteinases (MMPs) are a group of endopeptidases that play an important role in the degradation and remodeling of the ECM. Several recent studies have shown that the expression and activity of many MMP subgroups are significantly upregulated in degenerated IVD tissue. This upregulation of MMPs results in an imbalance of ECM anabolism and catabolism, leading to the degradation of the ECM and the development of IDD. Therefore, the regulation of MMP expression is a potential therapeutic target for the treatment of IDD. Recent research has focused on identifying the mechanisms by which MMPs cause ECM degradation and promote IDD, as well as on developing therapies that target MMPs. In summary, MMP dysregulation is a crucial factor in the development of IDD, and a deeper understanding of the mechanisms involved is needed to develop effective biological therapies that target MMPs to treat IDD.


Asunto(s)
Degeneración del Disco Intervertebral , Disco Intervertebral , Humanos , Degeneración del Disco Intervertebral/tratamiento farmacológico , Degeneración del Disco Intervertebral/metabolismo , Degeneración del Disco Intervertebral/patología , Matriz Extracelular/metabolismo , Regulación hacia Arriba , Activación Transcripcional , Metaloproteinasas de la Matriz/metabolismo , Disco Intervertebral/metabolismo , Disco Intervertebral/patología
10.
Mater Today Bio ; 22: 100748, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37600350

RESUMEN

Excellent biocompatibility, mechanical properties, chemical stability, and elastic modulus close to bone tissue make polyetheretherketone (PEEK) a promising orthopedic implant material. However, biological inertness has hindered the clinical applications of PEEK. The immune responses and inflammatory reactions after implantation would interfere with the osteogenic process. Eventually, the proliferation of fibrous tissue and the formation of fibrous capsules would result in a loose connection between PEEK and bone, leading to implantation failure. Previous studies focused on improving the osteogenic properties and antibacterial ability of PEEK with various modification techniques. However, few studies have been conducted on the immunomodulatory capacity of PEEK. New clinical applications and advances in processing technology, research, and reports on the immunomodulatory capacity of PEEK have received increasing attention in recent years. Researchers have designed numerous modification techniques, including drug delivery systems, surface chemical modifications, and surface porous treatments, to modulate the post-implantation immune response to address the regulatory factors of the mechanism. These studies provide essential ideas and technical preconditions for the development and research of the next generation of PEEK biological implant materials. This paper summarizes the mechanism by which the immune response after PEEK implantation leads to fibrous capsule formation; it also focuses on modification techniques to improve the anti-inflammatory and immunomodulatory abilities of PEEK. We also discuss the limitations of the existing modification techniques and present the corresponding future perspectives.

11.
Mater Today Bio ; 18: 100524, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36619202

RESUMEN

Spinal cord injuries (SCIs) are devastating. In SCIs, a powerful traumatic force impacting the spinal cord results in the permanent loss of nerve function below the injury level, leaving the patient paralyzed and wheelchair-bound for the remainder of his/her life. Unfortunately, clinical treatment that depends on surgical decompression appears to be unable to handle damaged nerves, and high-dose methylprednisolone-based therapy is also associated with problems, such as infection, gastrointestinal bleeding, femoral head necrosis, obesity, and hyperglycemia. Nanomaterials have opened new avenues for SCI treatment. Among them, performance-based nanomaterials derived from a variety of materials facilitate improvements in the microenvironment of traumatic injury and, in some cases, promote neuron regeneration. Nanoparticulate drug delivery systems enable the optimization of drug effects and drug bioavailability, thus contributing to the development of novel treatments. The improved efficiency and accuracy of gene delivery will also benefit the exploration of SCI mechanisms and the understanding of key genes and signaling pathways. Herein, we reviewed different types of nanomaterials applied to the treatment of SCI and summarized their functions and advantages to provide new perspectives for future clinical therapies.

12.
Front Cell Dev Biol ; 11: 1324561, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38313000

RESUMEN

Intervertebral disc (IVD) degeneration (IDD) is a worldwide spinal degenerative disease. Low back pain (LBP) is frequently caused by a variety of conditions brought on by IDD, including IVD herniation and spinal stenosis, etc. These conditions bring substantial physical and psychological pressure and economic burden to patients. IDD is closely tied with the structural or functional changes of the IVD tissue and can be caused by various complex factors like senescence, genetics, and trauma. The IVD dysfunction and structural changes can result from extracellular matrix (ECM) degradation, differentiation, inflammation, oxidative stress, mechanical stress, and senescence of IVD cells. At present, the treatment of IDD is basically to alleviate the symptoms, but not from the pathophysiological changes of IVD. Interestingly, the p38 mitogen-activated protein kinase (p38 MAPK) signaling pathway is involved in many processes of IDD, including inflammation, ECM degradation, apoptosis, senescence, proliferation, oxidative stress, and autophagy. These activities in degenerated IVD tissue are closely relevant to the development trend of IDD. Hence, the p38 MAPK signaling pathway may be a fitting curative target for IDD. In order to better understand the pathophysiological alterations of the intervertebral disc tissue during IDD and offer potential paths for targeted treatments for intervertebral disc degeneration, this article reviews the purpose of the p38 MAPK signaling pathway in IDD.

13.
Risk Manag Healthc Policy ; 16: 383-391, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36936882

RESUMEN

Aim: This study investigated the current status and related risk factors of 48-hour unplanned return to the intensive care unit (ICU) to reduce the return rate and improve the quality of critical care management. Methods: Data were collected from 2365 patients discharged from the comprehensive ICU. Multivariate and 1:1 propensity score matching analyses were performed. Results: Forty patients (1.69%) had unplanned readmission to the ICU within 48 hours after transfer. The primary reason for return was respiratory failure (16 patients, 40%). Furthermore, respiratory failure (odds ratio [OR] = 5.994, p = 0.02) and the number of organ failures (OR = 5.679, p = 0.006) were independent risk factors for unplanned ICU readmission. Receiver operating characteristic curves were drawn for the predictive value of the number of organ injuries during a patient's unplanned transfer to the ICU (area under the curve [AUC] = 0.744, sensitivity = 60%, specificity = 77.5%). Conclusion: The reason for patient transfer and the number of organ injuries during the process were independent risk factors for patients who were critically ill. The number of organs damaged had a predictive value on whether the patient would return to the ICU within 48 hours.

14.
Mol Biol Rep ; 39(3): 3097-102, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21691706

RESUMEN

To investigate the mutations of BRCA1 and BRCA2 and determine whether clinic-pathological factors related to BRCA gene mutation. Mastectomy specimens from 360 breast cancers were enrolled and examined in the study. The relationship between BRCA gene mutation and clinic-pathological factors was evaluated. Overall, 280 patients were BRCA negative and 80 got BRCA gene mutation. Triple-negative breast cancers--i.e., breast cancers that do not express estrogen receptors (ER), progesterone receptors (PR) or human epidermal growth factor receptor 2 (HER2/neu)--was observed in 53.85% of the BRCA1 mutation patients, in 28.57% of the BRCA2 mutation cases, while 14.29% of BRCA negative patients. BRCA1 mutation patients got a heavy lymph node metastasis and higher nuclear grade tumors than the others (P = 0.004, 0.007). Furthermore, BRCA mutation was also found to be significantly related to ER, PR and HER2/neu status (P < 0.05). BRCA1 expression was not associated with breast cancer-specific survival in the triple-negative breast cancers (P = 0.742). After Cox regression, BRCA1 mutation was not shown to be an independent prognostic factor for breast cancer. These findings substantiated the possibility of tumors associated with BRCA1 mutations divided into two distinct groups, triple-negative and non-triple-negative groups requires further investigation.


Asunto(s)
Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Genes BRCA1 , Genes BRCA2 , Mutación/genética , Adulto , Anciano , Neoplasias de la Mama/metabolismo , China/epidemiología , Femenino , Humanos , Inmunohistoquímica , Estimación de Kaplan-Meier , Metástasis Linfática/genética , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Receptor ErbB-2/metabolismo , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo
15.
Comput Intell Neurosci ; 2022: 4672586, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36072742

RESUMEN

In recent years, with the continuous development of machine learning technology, this technology has achieved success in many fields and activities. Therefore, using machine learning technology for fuzzy research has a good research prospect. In the development of related research, the author of this study noticed that some researchers began to use tennis machine learning technology and achieved good results. However, most of the research is only for simple analysis and is related to the current work. It cannot be used to move a solid tennis ball, nor it can make small changes to the original tennis movement; thus, it cannot carry out a complete and brand-new movement. The defense of tennis first establishes visual teaching tools with the help of various courses and visual teaching techniques to improve the teaching effect. By optimizing the network data, this study constructs the corresponding data search model, which downloads a large amount of data from the network ram, so as to separate the impact of the network environment on the load. The simulation results show that the model is optimized for the high-quality 3G network environment, and the load time and energy consumption are greatly reduced. It is more efficient in WiFi and a a high-quality 4G network environment.


Asunto(s)
Máquina de Vectores de Soporte , Tenis , Animales , Simulación por Computador , Visualización de Datos , Aprendizaje Automático , Masculino , Ovinos
16.
Front Bioeng Biotechnol ; 10: 931800, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35800332

RESUMEN

Traffic accidents and falling objects are responsible for most spinal cord injuries (SCIs). SCI is characterized by high disability and tends to occur among the young, seriously affecting patients' lives and quality of life. The key aims of repairing SCI include preventing secondary nerve injury, inhibiting glial scarring and inflammatory response, and promoting nerve regeneration. Hydrogels have good biocompatibility and degradability, low immunogenicity, and easy-to-adjust mechanical properties. While providing structural scaffolds for tissues, hydrogels can also be used as slow-release carriers in neural tissue engineering to promote cell proliferation, migration, and differentiation, as well as accelerate the repair of damaged tissue. This review discusses the characteristics of hydrogels and their advantages as delivery vehicles, as well as expounds on the progress made in hydrogel therapy (alone or combined with cells and molecules) to repair SCI. In addition, we discuss the prospects of hydrogels in clinical research and provide new ideas for the treatment of SCI.

17.
Orthop Surg ; 14(7): 1271-1280, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35486489

RESUMEN

Intervertebral disc degeneration (IDD) causes a variety of signs and symptoms, such as low back pain (LBP), intervertebral disc herniation, and spinal stenosis, which contribute to high social and economic costs. IDD results from many factors, including genetic factors, aging, mechanical injury, malnutrition, and so on. The pathological changes of IDD are mainly composed of the senescence and apoptosis of nucleus pulposus cells (NPCs), the progressive degeneration of extracellular matrix (ECM), the fibrosis of annulus fibrosus (AF), and the inflammatory response. At present, IDD can be treated by conservative treatment and surgical treatment based on patients' symptoms. However, all of these can only release the pain but cannot reverse IDD and reconstruct the mechanical function of the spine. The latest research is moving towards the field of biotherapy. Mesenchymal stem cells (MSCs) are regard as the potential therapy of IDD because of their ability to self-renew and differentiate into a variety of tissues. Moreover, the non-coding RNAs (ncRNAs) are found to regulate many vital processes in IDD. There have been many successes in the in vitro and animal studies of using biotherapy to treat IDD, but how to transform the experimental data to real therapy which can apply to humans is still a challenge. This article mainly reviews the treatment strategies and research progress of IDD and indicates that there are many problems that need to be solved if the new biotherapy is to be applied to clinical treatment of IDD. This will provide reference and guidance for clinical treatment and research direction of IDD.


Asunto(s)
Anillo Fibroso , Degeneración del Disco Intervertebral , Desplazamiento del Disco Intervertebral , Disco Intervertebral , Células Madre Mesenquimatosas , Núcleo Pulposo , Animales , Disco Intervertebral/patología , Degeneración del Disco Intervertebral/patología , Degeneración del Disco Intervertebral/terapia , Desplazamiento del Disco Intervertebral/patología , Núcleo Pulposo/patología
18.
Mater Today Bio ; 16: 100402, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36105676

RESUMEN

Polyetheretherketone (PEEK) has gradually become the mainstream material for preparing orthopedic implants due to its similar elastic modulus to human bone, high strength, excellent wear resistance, radiolucency, and biocompatibility. Since the 1990s, PEEK has increasingly been used in orthopedics. Yet, the widespread application of PEEK is limited by its bio-inertness, hydrophobicity, and susceptibility to microbial infections. Further enhancing the osteogenic properties of PEEK-based implants remains a difficult task. This article reviews some modification methods of PEEK in the last five years, including surface modification of PEEK or incorporating materials into the PEEK matrix. For surface modification, PEEK can be modified by chemical treatment, physical treatment, or surface coating with bioactive substances. For PEEK composite material, adding bioactive filler into PEEK through the melting blending method or 3D printing technology can increase the biological activity of PEEK. In addition, some modification methods such as sulfonation treatment of PEEK or grafting antibacterial substances on PEEK can enhance the antibacterial performance of PEEK. These strategies aim to improve the bioactive and antibacterial properties of the modified PEEK. The researchers believe that these modifications could provide valuable guidance on the future design of PEEK orthopedic implants.

19.
Orthop Surg ; 14(3): 577-586, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35147295

RESUMEN

OBJECTIVE: To study the effectiveness of a new spinal protection device for preventing and treating osteoporotic vertebral compression fractures (OVCFs) by finite element analysis (FEA). METHODS: One healthy volunteer and one patient with 1-segment lumbar vertebral compression fractures were included in this experimental study. The DICOM files of two different lumbar spiral computed tomography (CT) scans were converted into STL files, and 3D finite element models of the lumbar spine were generated for normal and L1 vertebral fracture spines. A new type of spinal protection device was applied to reduce the stress on the anterior vertebral edge and direct the center of gravity posteriorly. The stress distribution characteristics of different finite element models of the lumbar spine were analyzed, revealing the characteristics of the stress distributed along the spine under the action of the new spinal protection device. RESULTS: Under normal conditions, the stress was mainly distributed in the middle and posterior columns of the spine. When the anterior border of the L1 vertebral body was fractured and collapsed, the stress distribution shifted toward the anterior column due to the center of gravity being directed forward. According to finite element analysis of the spine with the new protection device, the stress in the middle and posterior columns tended to increase, and that in the anterior column decreased. After the new type of spinal fixation device was applied, the stress at the L1 and L2 vertebral endplates decreased to a certain extent, especially that at the L1 vertebral body. The maximum stress on the L1 vertebral body decreased by 20% after the auxiliary device was applied. CONCLUSIONS: According to the FEA results, the new spinal protection device can effectively prevent and treat osteoporotic vertebral compression fractures (OVCFs), and can alter the stress distribution in the spine and reduce the stress in the anterior column of the vertebral body, especially in vertebral compression fractures.


Asunto(s)
Fracturas por Compresión , Fracturas Osteoporóticas , Fracturas de la Columna Vertebral , Análisis de Elementos Finitos , Fracturas por Compresión/cirugía , Humanos , Vértebras Lumbares/lesiones , Vértebras Lumbares/cirugía , Fracturas Osteoporóticas/prevención & control , Fracturas Osteoporóticas/cirugía , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fracturas de la Columna Vertebral/prevención & control , Fracturas de la Columna Vertebral/cirugía
20.
J Mater Chem B ; 10(3): 456-467, 2022 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-34982090

RESUMEN

Bacterial infections and antibiotic resistance have become a global healthcare crisis. Herein, we designed and synthesized a series of cationic amphiphilic dendrons with cationic dendrons and hydrophobic alkyl chains for potential antibacterial applications. Our results showed that the antimicrobial activities of the cationic amphiphilic dendrons were highly dependent upon the length of the hydrophobic alkyl chain, whereas the number of cationic charges was less important. Among these cationic amphiphilic dendrons, a prime candidate was identified, which possessed excellent antimicrobial activity against various pathogens (minimum inhibitory concentrations of 9, 3, and 3 µg mL-1 for Escherichia coli, Staphylococcus aureus, and methicillin-resistant Staphylococcus aureus, respectively). Scanning electron microscopy and fluorescence microscopy analyses showed that it could disrupt the integrity of a pathogen's membrane, leading to cell lysis and death. In addition, in vitro bacteria-killing kinetics showed that it had rapid bactericidal efficiency. It also had excellent antimicrobial activities against MRSA in vivo and promoted wound healing. In general, the synthesized cationic amphiphilic dendrons, which exhibited rapid and broad-spectrum bactericidal activity, may have great potential in antimicrobial applications.


Asunto(s)
Antibacterianos/uso terapéutico , Dendrímeros/uso terapéutico , Infecciones Cutáneas Estafilocócicas/tratamiento farmacológico , Tensoactivos/uso terapéutico , Animales , Antibacterianos/síntesis química , Membrana Celular/efectos de los fármacos , Dendrímeros/síntesis química , Farmacorresistencia Bacteriana/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Interacciones Hidrofóbicas e Hidrofílicas , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Ratones , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Ratas , Infecciones Cutáneas Estafilocócicas/patología , Tensoactivos/síntesis química , Cicatrización de Heridas/efectos de los fármacos
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