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1.
Med Sci Monit ; 30: e943181, 2024 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-38366581

RESUMEN

The number of patients with malignant tumors is increasing in China, and venous access ports have unique advantages for chemotherapy. Currently, China's research on venous access port-mediated kinesiophobia is still in the developing stage. Using the combination of subjective words and freedom words, and based on literature traceability methods, China National Knowledge Infrastructure (CNKI), Wanfang, Vipp, Chinese Biomedical Database (CBM), Web of Science, The COCHRANE LIBRARY, Embase, and PubMed were searched. Relevant articles published from the construction of the database to October 30, 2023, were identified. Based on the many articles and analyses, the methods of assessing kinesiophobia in malignant tumors patients using venous access port, the related influencing factors and the preventive and intervention strategies were collated. We found 33 articles examining kinesiophobia in oncology patients, of which 4 were specifically conducted on patients with malignant tumors using VAPs or PICCs. The relevant preventive and therapeutic experiences regarding kinesiophobia in cancer patients with VAP still need improvement. Nursing staff can use assessment tools such as the Tampa Rating Scale for Kinesiophobia, the Fear Avoidance Beliefs Questionnaire, and the Cancer Fatigue Scale to reasonably and effectively assess kinesiophobia among patients with malignant tumors who use VAPs. Attention should be paid to the mechanisms and roles of demographic factors, pain and foreign body sensation, cancer fatigue, pain management strategies, and other factors influencing kinesiophobia. This study provides advice to nursing staff for the management of VAP. Such considerations may reduce the complications of kinesiophobia and improve the quality of life of patients.


Asunto(s)
Cateterismo Venoso Central , Neoplasias , Humanos , Kinesiofobia , Calidad de Vida , Neoplasias/complicaciones , Fatiga
2.
Dent Mater ; 38(11): 1812-1825, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36192277

RESUMEN

OBJECTIVES: This study aimed to determine the effects of the postwashing method and time on the mechanical properties and biocompatibility of three-dimensional (3D) printed crown and bridge resin. METHODS: DLP (digital light processing)-printed specimens produced from Nextdent crown & bridge (C&B) resins were washed separately using an ultrasonic bath and rotary washer with TPM (tripropylene glycol monomethyl ether) for 3 min, 6 min, 10 min, 20 min, and 1 h. Postcuring was applied for 30 min to each specimen after the washing process. The flexural strength, Vickers hardness, water sorption and solubility, degree of conversion (DC), elution of residual monomers, and biocompatibility of the specimens were evaluated. RESULTS: The ultrasonic bath showed greater washing efficacy by reducing the residual HEMA (2-hydroxyethyl methacrylate) from 2.0634 ppm to 0.1456 ppm and reducing the residual TEGDMA (triethylene glycol dimethacrylate) from 1.4862 ppm to 0.1484 ppm. With prolonged washing, the flexural strength significantly decreased from 129.67 ± 6.66 MPa (mean±standard deviation) to 103.17 ± 7.20 MPa, while the Vickers hardness increased slightly for the first 6 min and then decreased thereafter significantly. The DC was 87.78 ± 1.34% after 3 min and then gradually decreased with extended washing time. The cytotoxicity significantly decreases with the increment of the washing time. SIGNIFICANCE: The washing effect on the elution of residual monomers was better for an ultrasonic bath than for a rotary washer. Extending the washing time reduces the mechanical properties and cytotoxicity of the Nextdent C&B resin.


Asunto(s)
Resinas Compuestas , Coronas , Éteres , Ensayo de Materiales , Metacrilatos , Polietilenglicoles , Ácidos Polimetacrílicos , Impresión Tridimensional , Agua
3.
J Mech Behav Biomed Mater ; 130: 105170, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35334279

RESUMEN

The photosensitive resin used in additive manufacturing is cured by free radical polymerization by UV irradiation. However, undesired reaction with oxygen during polymerization inhibits polymerization and results in an under-cured polymer. Therefore, in this study, the hypothesis that successful oxygen shielding in the post-polymerization step could affect the properties of the final polymer was tested. 3D printed specimens using denture base resin were post polymerized either by immersion in glycerin for oxygen shielding (GL group) or placed in a medium-low vacuum chamber at 5 × 10-2 Torr (VA group). Specimens cured with no additional conditioning served as the control (CON group). To consider the effect of temperature, all groups were additionally compared with 80 °C and without an increase in temperature (room temperature) during post-polymerization. Fourier transform infrared spectroscopy was used to measure the monomer conversion ratios between different groups. In addition, the mechanical properties were quantified by the micro-hardness, flexural strength, and elasticity of the surface, and the water sorption and solubility. Dynamic mechanical analysis (DMA) was conducted to observe the trend in storage and loss modulus between the groups against temperature. Differences in the surface as a function of the post-polymerization conditions were qualitatively observed by scanning electron microscopy (SEM). The result shows that oxygen shielding during post-polymerization showed an increase in the degree of conversion (DC) and hardness of the resin surface. The highest DC was observed for GL group specimens at both room temperature and 80 °C. This result was confirmed by the SEM micrographs of the resin surface, where the interface between the layers of the GL group structure becomes more robust. However, a difference was observed between the samples prepared at room temperature and 80 °C. The flexural modulus was highest in the GL group, followed by the VA group, and lowest in the CON group at 80 °C. No difference in water absorption was observed for any groups, but high water solubility was observed in the GL group at room temperature. Overall, more significant differences in the properties were observed for the samples post-polymerized at 80 °C than at room temperature. The results of DMA analysis to determine the glass transition temperature showed a similar trend in all groups, and the storage modulus and loss rate obtained in the same experiment decreased in the order of GL, CON, and VA. In conclusion, an oxygen shielded post-polymerization environment at elevated temperature effectively improves the mechanical properties of photosensitive resin.


Asunto(s)
Glicerol , Oxígeno , Resinas Compuestas , Dureza , Ensayo de Materiales , Polimerizacion , Polímeros/química , Impresión Tridimensional , Propiedades de Superficie , Temperatura , Vacio , Agua/química
4.
J Mech Behav Biomed Mater ; 128: 105127, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35182913

RESUMEN

This study analyzed the flexural properties, Vickers hardness, degree of conversion (DC), and cell viability of 3D printed crown and bridge resin postcured using various types of postcuring equipment (PCE). 3D printed specimens were postcured for various times using different types of 3D printing PCE [for 5, 15, and 30 min using LC 3D Print Box (LC), Form Cure (FC), Cure M (CM), and Veltz 3D (VE) devices] and the VALO handheld light-curing (VA) device for 20, 40, and 60 s. Neither the flexural strength (132.27-145.79 MPa) nor the flexural modulus (1.52-1.83 GPa) differed significantly when postcuring for 30 min using the LC, FC, CM, or VE device, or for 20, 40, or 60 s of postcuring using the VA device (p > 0.05). The Vickers hardness was highest after 30 min of postcuring for all groups, and varied significantly with the postcuring time in the LC (p < 0.001) and CM (p < 0.001) groups. DC was significantly higher for the 5-min CM group (84.97 ± 4.02%) than for the GS, 30-min FC, 5-min VE, and 20-s VA groups. Cell viability of the postcured resin specimens was 56.46-92.29%, and varied significantly in the CM and VE groups according to the postcuring time (p < 0.05). Confocal laser scanning microscopy observations showed well-developed cell morphology and numerous cell-cell contacts in all groups except the GS group. This study found that the use of different types of PCE did not significantly affect the flexural properties of 3D printed crown and bridge resin, whereas there were significant variations in DC, Vickers hardness, and cell viability.


Asunto(s)
Coronas , Resistencia Flexional , Resinas Compuestas , Ensayo de Materiales , Impresión Tridimensional , Propiedades de Superficie
5.
Bone ; 127: 220-227, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31216497

RESUMEN

Osteocalcin is an osteoblast-specific secreted protein that has been associated with endocrine roles in multiple aspects of energy metabolism. We examined whether undercarboxylated osteocalcin (ucOC) downregulates pancreatic lipase (PNLIP) expression in pancreatic acinar cells and then identified the downstream signaling pathway involved. We previously demonstrated that ß adrenergic blockade attenuates body weight/fat mass gain in high-fat diet-fed mice and that this effect is associated with decreased PNLIP expression in pancreatic acinar cells. In the present study, we first confirmed that the serum ucOC level is inversely correlated with PNLIP expression, i.e., mice exhibiting high serum levels of ucOC showed low PNLIP levels in the pancreas. In in vitro experiments using primary pancreatic acinar and 266-6 cells, ucOC downregulated PNLIP expression. cAMP/PKA signaling inhibitors significantly reversed ucOC-induced downregulation of PNLIP expression. ucOC promoted the phosphorylation of cAMP response element-binding protein 2 (ATF4). Overexpression of ATF4 significantly suppressed PNLIP expression. Knockdown of ATF4 by siRNA reversed the ucOC-induced downregulation of PNLIP expression. A luciferase reporter assay showed that ucOC suppressed PNLIP promoter transactivation. Chromatin immunoprecipitation and a luciferase reporter assay demonstrated that ATF4 directly bound to the CRE on the mouse PNLIP promoter and suppressed PNLIP transactivation. Knockdown of G-protein coupled receptor 6A (Gprc6a), a candidate receptor for mediating the response to ucOC in the bone-pancreas endocrine loop, by siRNA reversed the downregulating effect of ucOC on PNLIP expression. Taken together, ucOC downregulates pancreatic lipase expression in a cAMP/protein kinase A/ATF4-dependent manner. Gprc6a is a potential osteocalcin-sensing receptor that regulates PNLIP expression in pancreatic acinar cells.


Asunto(s)
Células Acinares/metabolismo , Factor de Transcripción Activador 4/metabolismo , Regulación hacia Abajo , Lipasa/metabolismo , Osteocalcina/metabolismo , Páncreas/enzimología , Animales , Secuencia de Bases , Línea Celular , AMP Cíclico/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Humanos , Masculino , Ratones Endogámicos C57BL , Osteocalcina/sangre , Regiones Promotoras Genéticas/genética , Unión Proteica , Receptores Acoplados a Proteínas G/metabolismo , Transducción de Señal
6.
Int J Mol Sci ; 19(1)2018 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-29315243

RESUMEN

Hyperglycemic conditions in diabetic patients can affect various cellular functions, including the modulation of osteogenic differentiation. However, the molecular mechanisms by which hyperglycemia affects osteogenic differentiation are yet to be clarified. This study aimed to investigate whether the aberrant increase in protein O-linked-ß-N-acetylglucosamine glycosylation (O-GlcNAcylation) contributes to the suppression of osteogenic differentiation due to hyperglycemia. To induce osteogenic differentiation, C2C12 cells were cultured in the presence of recombinant human bone morphogenetic protein 2 (BMP2). Excessive protein O-GlcNAcylation was induced by treating C2C12 cells with high glucose, glucosamine, or N-acetylglucosamine concentrations or by O-GlcNAc transferase (OGT) overexpression. The effect of O-GlcNAcylation on osteoblast differentiation was then confirmed by examining the expression levels of osteogenic marker gene mRNAs, activity of alkaline phosphatase, and transcriptional activity of Runx2, a critical transcription factor for osteoblast differentiation and bone formation. Cell treatment with high glucose, glucosamine or N-acetylglucosamine increased O-GlcNAcylation of Runx2 and the total levels of O-GlcNAcylated proteins, which led to a decrease in the transcriptional activity of Runx2, expression levels of osteogenic marker genes (Runx2, osterix, alkaline phosphatase, and type I collagen), and activity of alkaline phosphatase. These inhibitory effects were rescued by lowering protein O-GlcNAcylation levels by adding STO45849, an OGT inhibitor, or by overexpressing ß-N-acetylglucosaminidase. Our findings suggest that excessive protein O-GlcNAcylation contributes to high glucose-suppressed osteogenic differentiation.


Asunto(s)
Proteína Morfogenética Ósea 2/farmacología , Diferenciación Celular/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Factor de Crecimiento Transformador beta/farmacología , Fosfatasa Alcalina/genética , Fosfatasa Alcalina/metabolismo , Animales , Células Cultivadas , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Subunidad alfa 1 del Factor de Unión al Sitio Principal/genética , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Inhibidores Enzimáticos/farmacología , Glucosamina/farmacología , Glucosa/farmacología , Glicosilación/efectos de los fármacos , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Humanos , Ratones , Mioblastos/citología , Mioblastos/efectos de los fármacos , Mioblastos/metabolismo , N-Acetilglucosaminiltransferasas/antagonistas & inhibidores , N-Acetilglucosaminiltransferasas/genética , N-Acetilglucosaminiltransferasas/metabolismo , Ligamento Periodontal/citología , Ligamento Periodontal/efectos de los fármacos , Ligamento Periodontal/metabolismo , Proteínas Recombinantes/farmacología , Factor de Transcripción Sp7/genética , Factor de Transcripción Sp7/metabolismo , Transcripción Genética/efectos de los fármacos
7.
J Med Food ; 21(1): 57-69, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28981378

RESUMEN

Morinda citrifolia (Noni) leaf is an herbal medicine with application in the domestic treatment of a broad range of conditions, including bone fracture and luxation. However, the basic mechanism underlying the stimulation of osteogenic differentiation by Noni leaf extract remains poorly understood. This study aimed to examine the effect of this extract on osteogenic differentiation and the mechanism by which Noni leaf extract enhances osteogenic differentiation. Aqueous extract of Noni leaves was prepared, and rutin and kaempferol-3-O-rutinoside were identified to be two of its major components. C2C12 and human periodontal ligament (hPDL) cells were used to study the effect of Noni. Noni did not show cytotoxicity at a concentration range of 0.015%-1.0% (w/v%) and significantly enhanced the activity of alkaline phosphatase (ALP) and expression levels of osteoblast differentiation markers, including Runx2, ALP, osterix, and osteocalcin, bone morphogenetic protein 2, Wnt3a, and ß-catenin. In addition, Noni enhanced the matrix mineralization of hPDL cells. In the signaling pathways, Noni increased the phosphorylation levels of Akt and GSK3ß and nuclear translocation and transcriptional activity of ß-catenin, which were attenuated by the addition of Dkk-1, a Wnt inhibitor, or LY294002, a PI3K inhibitor. These results suggest that Noni leaf extract enhances osteogenic differentiation through the PI3K/Akt-dependent activation of Wnt/ß-catenin signaling. Noni leaf extract might be a novel alternative medicine for bone and periodontal regeneration in patients with periodontal diseases.


Asunto(s)
Morinda/química , Osteoblastos/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Extractos Vegetales/farmacología , Vía de Señalización Wnt/efectos de los fármacos , beta Catenina/metabolismo , Fosfatasa Alcalina/genética , Fosfatasa Alcalina/metabolismo , Animales , Proteína Morfogenética Ósea 2/genética , Proteína Morfogenética Ósea 2/metabolismo , Línea Celular , Ratones , Osteoblastos/citología , Osteoblastos/metabolismo , Osteocalcina/genética , Osteocalcina/metabolismo , Hojas de la Planta/química , Proteína Wnt3A/genética , Proteína Wnt3A/metabolismo , beta Catenina/genética
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