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1.
Phys Chem Chem Phys ; 26(19): 14131-14139, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38690682

RESUMEN

Cancer is one of the primary health concerns among humans due to its high incidence rate and lack of effective treatment. Currently, medical techniques to achieve the precise elimination of local cancer lesions with negligible damage to normal tissues are still intensely desired. Herein, we synthesized BaTiO3-TiO2 hollow spheres (BTHSs) for use in microwave dynamic therapy (MWDT) for cancer. Under UV irradiation, BTHSs can mediate the production of multiple reactive oxygen species (ROS), mainly 1O2, which results in a rapid photocatalytic degradation rate (97%), 1.6-fold that of commercial P25. Importantly, the ROS production process can be triggered by microwaves to effectively execute MWDT for cancer. Under microwave irradiation, BTHSs exhibit a remarkable therapeutic effect and slight cytotoxicity. In terms of mechanism, the enhanced ROS production efficiency of BTHSs can be attributed to their unique hollow structure and the formation of a type-II heterojunction by the incorporation of BaTiO3. The hollow structure increases the availability of active sites and enhances light scattering, while the BaTiO3-TiO2 heterojunction enhances the photocatalytic activity of TiO2 through charge transfer and electron-hole separation. Overall, this study provides important insights into the design and optimization of sensitizers for MWDT applications.


Asunto(s)
Compuestos de Bario , Microondas , Especies Reactivas de Oxígeno , Titanio , Titanio/química , Compuestos de Bario/química , Humanos , Especies Reactivas de Oxígeno/metabolismo , Supervivencia Celular/efectos de los fármacos , Neoplasias , Catálisis , Antineoplásicos/química , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico
2.
J Nanobiotechnology ; 22(1): 242, 2024 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-38735936

RESUMEN

BACKGROUND: Two-dimensional ultrathin Ti3C2 (MXene) nanosheets have gained significant attention in various biomedical applications. Although previous studies have described the accumulation and associated damage of Ti3C2 nanosheets in the testes and placenta. However, it is currently unclear whether Ti3C2 nanosheets can be translocated to the ovaries and cause ovarian damage, thereby impairing ovarian functions. RESULTS: We established a mouse model with different doses (1.25, 2.5, and 5 mg/kg bw/d) of Ti3C2 nanosheets injected intravenously for three days. We demonstrated that Ti3C2 nanosheets can enter the ovaries and were internalized by granulosa cells, leading to a decrease in the number of primary, secondary and antral follicles. Furthermore, the decrease in follicles is closely associated with higher levels of FSH and LH, as well as increased level of E2 and P4, and decreased level of T in mouse ovary. In further studies, we found that exposure toTi3C2 nanosheets increased the levels of Beclin1, ATG5, and the ratio of LC3II/Ι, leading to autophagy activation. Additionally, the level of P62 increased, resulting in autophagic flux blockade. Ti3C2 nanosheets can activate autophagy through the PI3K/AKT/mTOR signaling pathway, with oxidative stress playing an important role in this process. Therefore, we chose the ovarian granulosa cell line (KGN cells) for in vitro validation of the impact of autophagy on the hormone secretion capability. The inhibition of autophagy initiation by 3-Methyladenine (3-MA) promoted smooth autophagic flow, thereby partially reduced the secretion of estradiol and progesterone by KGN cells; Whereas blocking autophagic flux by Rapamycin (RAPA) further exacerbated the secretion of estradiol and progesterone in cells. CONCLUSION: Ti3C2 nanosheet-induced increased secretion of hormones in the ovary is mediated through the activation of autophagy and impairment of autophagic flux, which disrupts normal follicular development. These results imply that autophagy dysfunction may be one of the underlying mechanisms of Ti3C2-induced damage to ovarian granulosa cells. Our findings further reveal the mechanism of female reproductive toxicity induced by Ti3C2 nanosheets.


Asunto(s)
Autofagia , Células de la Granulosa , Nanoestructuras , Ovario , Titanio , Animales , Femenino , Autofagia/efectos de los fármacos , Titanio/toxicidad , Titanio/química , Titanio/farmacología , Ratones , Ovario/efectos de los fármacos , Ovario/metabolismo , Nanoestructuras/química , Células de la Granulosa/efectos de los fármacos , Células de la Granulosa/metabolismo , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Folículo Ovárico/efectos de los fármacos , Folículo Ovárico/metabolismo , Estrés Oxidativo/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo
3.
Sci Adv ; 10(19): eadm9561, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38718119

RESUMEN

Lactic acid (LA) accumulation in the tumor microenvironment poses notable challenges to effective tumor immunotherapy. Here, an intelligent tumor treatment microrobot based on the unique physiological structure and metabolic characteristics of Veillonella atypica (VA) is proposed by loading Staphylococcus aureus cell membrane-coating BaTiO3 nanocubes (SAM@BTO) on the surface of VA cells (VA-SAM@BTO) via click chemical reaction. Following oral administration, VA-SAM@BTO accurately targeted orthotopic colorectal cancer through inflammatory targeting of SAM and hypoxic targeting of VA. Under in vitro ultrasonic stimulation, BTO catalyzed two reduction reactions (O2 → •O2- and CO2 → CO) and three oxidation reactions (H2O → •OH, GSH → GSSG, and LA → PA) simultaneously, effectively inducing immunogenic death of tumor cells. BTO catalyzed the oxidative coupling of VA cells metabolized LA, effectively disrupting the immunosuppressive microenvironment, improving dendritic cell maturation and macrophage M1 polarization, and increasing effector T cell proportions while decreasing regulatory T cell numbers, which facilitates synergetic catalysis and immunotherapy.


Asunto(s)
Neoplasias Colorrectales , Inmunoterapia , Microambiente Tumoral , Neoplasias Colorrectales/terapia , Neoplasias Colorrectales/inmunología , Neoplasias Colorrectales/patología , Inmunoterapia/métodos , Animales , Ratones , Humanos , Catálisis , Línea Celular Tumoral , Nanoestructuras/química , Materiales Biomiméticos/química , Administración Oral , Titanio/química , Biomimética/métodos , Ácido Láctico/química , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Compuestos de Bario
4.
ACS Biomater Sci Eng ; 10(5): 3255-3267, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38684056

RESUMEN

Osteoporosis is a metabolic disease characterized by bone density and trabecular bone loss. Bone loss may affect dental implant osseointegration in patients with osteoporosis. To promote implant osseointegration in osteoporotic patients, we further used a nonthermal atmospheric plasma (NTAP) treatment device previously developed by our research group. After the titanium implant (Ti) is placed into the device, the working gas flow and the electrode switches are turned on, and the treatment is completed in 30 s. Previous studies showed that this NTAP device can remove carbon contamination from the implant surface, increase the hydroxyl groups, and improve its wettability to promote osseointegration in normal conditions. In this study, we demonstrated the tremendous osteogenic enhancement effect of NTAP-Ti in osteoporotic conditions in rats for the first time. Compared to Ti, the proliferative potential of osteoporotic bone marrow mesenchymal stem cells on NTAP-Ti increased by 180% at 1 day (P = 0.004), while their osteogenic differentiation increased by 149% at 14 days (P < 0.001). In addition, the results indicated that NTAP-Ti significantly improved osseointegration in osteoporotic rats in vivo. Compared to the Ti, the bone volume fraction (BV/TV) and trabecular number (Tb.N) values of NTAP-Ti in osteoporotic rats, respectively, increased by 18% (P < 0.001) and 25% (P = 0.007) at 6 weeks and the trabecular separation (Tb.Sp) value decreased by 26% (P = 0.02) at 6 weeks. In conclusion, this study proved a novel NTAP irradiation titanium implant that can significantly promote osseointegration in osteoporotic conditions.


Asunto(s)
Células Madre Mesenquimatosas , Oseointegración , Osteogénesis , Osteoporosis , Gases em Plasma , Ratas Sprague-Dawley , Titanio , Titanio/farmacología , Animales , Osteogénesis/efectos de los fármacos , Osteoporosis/patología , Osteoporosis/terapia , Osteoporosis/tratamiento farmacológico , Gases em Plasma/farmacología , Gases em Plasma/uso terapéutico , Oseointegración/efectos de los fármacos , Femenino , Ratas , Células Madre Mesenquimatosas/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Prótesis e Implantes
5.
Colloids Surf B Biointerfaces ; 238: 113891, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38615392

RESUMEN

The three-dimensional-printed Ti6Al4V implant (3DTi) has been widely accepted for the reconstruction of massive bone defects in orthopedics owing to several advantages, such as its tailored shape design, avoiding bone graft and superior bone-implant interlock. However, the osteoinduction activity of 3DTi is inadequate when applied clinically even though it exhibits osteoconduction. This study developes a comprehensive coatless strategy for the surface improvement of 3DTi through copper (Cu) ion implantation and ultraviolet (UV) photofunctionalization to enhance osteoinductivity. The newly constructed functional 3DTi (UV/Ti-Cu) achieved stable and controllable Cu doping, sustained Cu2+ releasing, and increased surface hydrophilicity. By performing cellular experiments, we determined that the safe dose range of Cu ion implantation was less than 5×1016 ions/cm2. The implanted Cu2+ enhanced the ALP activity and the apatite formation ability of bone marrow stromal cells (BMSCs) while slightly decreasing proliferation ability. When combined with UV photofunctionalization, cell adhesion and proliferation were significantly promoted and bone mineralization was further increased. Meanwhile, UV/Ti-Cu was conducive to the migration and angiogenesis of human umbilical vein endothelial cells (HUVECs) in vitro, theoretically facilitating vascular coupling osteogenesis. In conclusion, UV/Ti-Cu is a novel attempt to apply two coatless techniques for the surface modification of 3DTi. In addition, it is considered a potential bone substrate for repairing bone defects.


Asunto(s)
Aleaciones , Adhesión Celular , Cobre , Células Endoteliales de la Vena Umbilical Humana , Neovascularización Fisiológica , Osteogénesis , Impresión Tridimensional , Titanio , Rayos Ultravioleta , Titanio/química , Titanio/farmacología , Aleaciones/química , Aleaciones/farmacología , Osteogénesis/efectos de los fármacos , Cobre/química , Cobre/farmacología , Adhesión Celular/efectos de los fármacos , Humanos , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Neovascularización Fisiológica/efectos de los fármacos , Animales , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/efectos de los fármacos , Propiedades de Superficie , Iones/química , Proliferación Celular/efectos de los fármacos , Prótesis e Implantes , Células Cultivadas , Angiogénesis
6.
J Mater Sci Mater Med ; 35(1): 25, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38635066

RESUMEN

Bioactive, nanoporous TiO2-coating has been shown to enhance cell attachment on titanium implant surface. The aim of this study was to evaluate, whether the saliva proteins affect the epithelial cell adhesion on TiO2-coated and non-coated titanium. Grade V titanium discs were polished. Half of the discs were provided with TiO2-coating produced in sol with polycondensation method. Half of the TiO2-coated and non-coated discs were treated with pasteurized saliva for 30 min. After saliva treatment, the total protein amounts on surfaces were measured. Next, the hydrophilicity of discs were measured with water contact angle measurements. Further, the gingival keratinocyte adhesion strength was measured after 2 and 6 h of cultivation using serial trypsinization. In addition, cell growth and proliferation were measured after 1, 3, and 7 days of cell culture. Finally, cell morphology, spreading and adhesion protein signals were detected with high resolution confocal microscopy. As a result, in sol coated TiO2-surface had significantly higher hydrophilicity when compared to non-coated titanium, meanwhile both non-coated and TiO2-coated surfaces with saliva treatment had a significant increase in hydrophilicity. Importantly, the amounts of adhered saliva proteins were equal between TiO2-coated and non-coated surfaces. Adhesion strength against enzymatic detachment was weakest on non-coated titanium after saliva exposure. Cell proliferation and cell spreading were highest on TiO2-coated titanium, but saliva exposure significantly decreased cell proliferation and spreading on TiO2-coated surface. To conclude, even though saliva exposure makes titanium surfaces more hydrophilic, it seems to neutralize the bioactive TiO2-coating and decrease cell attachment to TiO2-coated surface.


Asunto(s)
Saliva , Titanio , Queratinocitos , Proliferación Celular , Células Epiteliales
7.
J Indian Prosthodont Soc ; 24(2): 175-185, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38650343

RESUMEN

AIM: To evaluate the potential of iron nanoparticles (FeNPs) in conjunction with magnetic fields (MFs) to enhance osteoblast cytomechanics, promote cell homing, bone development activity, and antibacterial capabilities, and to assess their in vivo angiogenic viability using the chicken egg chorioallantoic membrane (CAM) model. SETTINGS AND DESIGN: Experimental study conducted in a laboratory setting to investigate the effects of FeNPs and MFs on osteoblast cells and angiogenesis using a custom titanium (Ti) substrate coated with FeNPs. MATERIALS AND METHODS: A custom titanium (Ti) was coated with FeNPs. Evaluations were conducted to analyze the antibacterial properties, cell adhesion, durability, physical characteristics, and nanoparticle absorption associated with FeNPs. Cell physical characteristics were assessed using protein markers, and microscopy, CAM model, was used to quantify blood vessel formation and morphology to assess the FeNP-coated Ti's angiogenic potential. This in vivo study provided critical insights into tissue response and regenerative properties for biomedical applications. STATISTICAL ANALYSIS: Statistical analysis was performed using appropriate tests to compare experimental groups and controls. Significance was determined at P < 0.05. RESULTS: FeNPs and MFs notably improved osteoblast cell mechanical properties facilitated the growth and formation of new blood vessels and bone tissue and promoted cell migration to targeted sites. In the group treated with FeNPs and exposed to MFs, there was a significant increase in vessel percentage area (76.03%) compared to control groups (58.11%), along with enhanced mineralization and robust antibacterial effects (P < 0.05). CONCLUSION: The study highlights the promising potential of FeNPs in fostering the growth of new blood vessels, promoting the formation of bone tissue, and facilitating targeted cell migration. These findings underscore the importance of further investigating the mechanical traits of FeNPs, as they could significantly advance the development of effective bone tissue engineering techniques, ultimately enhancing clinical outcomes in the field.


Asunto(s)
Membrana Corioalantoides , Campos Magnéticos , Neovascularización Fisiológica , Osteoblastos , Ingeniería de Tejidos , Titanio , Animales , Ingeniería de Tejidos/métodos , Membrana Corioalantoides/irrigación sanguínea , Membrana Corioalantoides/efectos de los fármacos , Neovascularización Fisiológica/efectos de los fármacos , Neovascularización Fisiológica/fisiología , Osteoblastos/efectos de los fármacos , Titanio/química , Titanio/farmacología , Embrión de Pollo , Pollos , Hierro/química , Nanopartículas del Metal/química , Antibacterianos/farmacología , Antibacterianos/química , Adhesión Celular/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Osteogénesis/fisiología , Angiogénesis
8.
J Chromatogr A ; 1725: 464875, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38678692

RESUMEN

Ultrasonic-assisted dispersive micro solid phase extraction (UA-DMSPE) is proposed as a fast and easy technique for the extraction and preconcentration of methadone and tramadol from serum samples. Different sorbents including carbon nanotubes, oxidized carbon nanotubes, and TiO2 nanoparticles were compared to extract methadone and tramadol. The best performance was obtained using oxidized carbon nanotubes due to the strong affinity between the drugs and carbon nanotube adsorbents. Final analysis of drugs performed by using gas chromatography-mass spectrometric detection. Different parameters affecting the extraction efficiency, such as the sample volume, amount of adsorbent, desorption solvent type and volume, centrifugation time, and speed were investigated and optimized. The striking features of this technique are correlated to its speed and the small volumes of sample (about 1 mL), desorption solvent (about 50 µL), and adsorbent (about 0.001 g) for analysis of drugs, and finally, milder centrifugation conditions relative to the previously reported adsorbent. The optimal parameters were achieved as follows: pH value was set at 9, the sample volume was adjusted to 1200 µL, the amount of adsorbent used was 1 mg, the extraction time was set at 5 min, and the volume of the desorption solvent was adjusted to 50 µL. The limits of detections (0.5 and 0.8 ng mL-1) and quantifications (1.5 and 2.5 ng mL-1) were obtained for methadone and tramadol, respectively. The developed method also showed good repeatability, relative standard deviation (RSD) of 9.49 % and 7.47 % (n = 5), for the spiked aqueous solution at the concentration level of 10, 50, and 100 ng mL-1 for analytes, and linearity, R ≥ 0.9809. The results showed that UA-DMSPE is a quick, relatively inexpensive, and environmentally friendly alternative technique for the extraction of opiate drugs from serum samples.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas , Límite de Detección , Metadona , Microextracción en Fase Sólida , Tramadol , Tramadol/sangre , Metadona/sangre , Cromatografía de Gases y Espectrometría de Masas/métodos , Humanos , Microextracción en Fase Sólida/métodos , Nanotubos de Carbono/química , Reproducibilidad de los Resultados , Adsorción , Titanio
9.
Int J Mol Sci ; 25(7)2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38612848

RESUMEN

The rational design of advanced electrocatalysts at the molecular or atomic level is important for improving the performance of hydrogen evolution reactions (HERs) and replacing precious metal catalysts. In this study, we describe the fabrication of electrocatalysts based on Fe, Co, or Ni single atoms supported on titanium carbide (TiC) using the molten salt method, i.e., TiC-FeSA, TiC-CoSA, or TiC-NiSA, to enhance HER performance. The introduction of uniformly distributed transition-metal single atoms successfully reduces the overpotential of HERs. Overpotentials of TiC-FeSA at 10 mA cm-2 are 123.4 mV with 61.1 mV dec-1 Tafel slope under acidic conditions and 184.2 mV with 85.1 mV dec-1 Tafel slope under alkaline conditions, which are superior to TiC-NiSA and TiC-CoSA. TiC samples loaded with transition-metal single atoms exhibit high catalytic activity and long stability under acidic and basic conditions. Density functional theory calculations indicate that the introduction of transition-metal single atoms effectively reduces the HER barrier of TiC-based electrocatalysts.


Asunto(s)
Hierro , Níquel , Titanio , Cobalto , Hidrógeno
10.
Zhongguo Gu Shang ; 37(4): 352-7, 2024 Apr 25.
Artículo en Chino | MEDLINE | ID: mdl-38664204

RESUMEN

OBJECTIVE: To compare the clinical outcomes of using elastic intramedullary nail and plate to fix fibular fracture. METHODS: The 60 patients with tibiofibular fractures admitted from January 2015 to December 2022 were divided into two groups:intramedullary nail group and plate group, 30 cases each, intramedullary nail group was treated with elastic intramedullary nail fixation group, plate group was treated with steel plate and screw fixation group. Intramedullary nail group, there were 18 males and 12 females, aged from 22 to 75 years old with an average of (39.4±9.8) years old, including 24 cases of traffic accidents injury, 6 cases of falling injury, 23 cases of closed fractures, 7 cases of open fractures. Steel plate group, there were 15 males and 15 females, aged from 24 to 78 years old with an average of (38.6±10.2) years old. The 22 cases were injured by traffic accident, 8 cases were injured by falling. The 24 cases were closed fractures and 6 cases were open fractures. The operation time, intraoperative bleeding, American Orthopedic Foot and Ankle Society (AOFAS) ankle and hind foot scores, clinical healing time of fibula and the incidence of wound complications were compared between the two groups. RESULTS: The patients in both groups were followed up for 6 to 21 months, with an average of (14.0±2.8) months. Compared with plate group, intramedullary nail group had shorter operative time, less bleeding, shorter clinical healing time of fibula, and lower infection rate of incision, and the difference was statistically significant (P<0.05). There were 2 cases of delayed healing in intramedullary nail group, 1 case of nonunion in plate group, and 2 cases of delayed healing in plate group, and there was no statistically significant difference between the two groups (P>0.05). In the last follow-up, according to the AOFAS scoring standard, the ankle function in intramedullary nail group was excellent in 17 cases, good in 12 cases, fair in 1 case, with an average of (88.33±4.57) points, while in plate group, excellent in 16 cases, good in 10 cases, fair in 4 cases, with an average of (87.00±4.14) points;There was no statistical difference between the two groups (P>0.05). CONCLUSION: Elastic intramedullary nail has the advantages of short operation time, less intraoperative bleeding, short fracture healing time and less incision complications in the treatment of fibular fracture, which is worthy of clinical application.


Asunto(s)
Clavos Ortopédicos , Placas Óseas , Peroné , Fracturas de la Tibia , Humanos , Masculino , Femenino , Persona de Mediana Edad , Adulto , Anciano , Peroné/lesiones , Peroné/cirugía , Fracturas de la Tibia/cirugía , Titanio , Fijación Intramedular de Fracturas/métodos , Fijación Intramedular de Fracturas/instrumentación , Adulto Joven , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Fijación Interna de Fracturas/métodos , Fijación Interna de Fracturas/instrumentación , Acero
11.
J Cardiothorac Surg ; 19(1): 245, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38632587

RESUMEN

BACKGROUND: Very large chest wall resections can lead to acute thoracic insufficiency syndrome due to the interdependence of lung expansion and thoracic volume. Chest wall tumor surgeries often encounter complications, with the size of the chest wall defect being a significant predictor. Several methods for large chest wall reconstruction have been described, aiming to provide stability, prevent flail chest, and ensure airtight closure. However, no single method fulfills all requirements. Composite chest wall reconstruction using titanium plates and Gore-Tex patches has shown the potential to minimize physiologic abnormalities caused by extensive defects. CASE PRESENTATION: A 42-year-old man with myxofibrosarcoma underwent multiple surgeries, chemotherapies, and radiation therapies due to repeated local recurrences. After right arm amputation and resection of the right third to fifth ribs, a local recurrence was detected. A 30 × 40 cm chest wall defect was resected en bloc, and a titanium plate was used for three-dimensional formability, preventing flail chest and volume loss. The Gore-Tex patch was then reconstructed into an arch shape, allowing lateral thoracic mobility. The patient recovered well and did not experience respiratory dysfunction or local recurrence but later succumbed to distant metastasis. CONCLUSIONS: In this case, the combination of a titanium plate and a Gore-Tex patch proved effective for reconstructing massive lateral chest wall defects. The approach provided stability, preserved thoracic volume, and allowed for lateral mobility. While the patient achieved a successful outcome in terms of local recurrence and respiratory function, distant metastasis remained a challenge for myxofibrosarcoma patients, and its impact on long-term prognosis requires further investigation. Nevertheless, the described procedure offers promise for managing extensive chest wall defects.


Asunto(s)
Tórax Paradójico , Sarcoma , Neoplasias Torácicas , Pared Torácica , Masculino , Humanos , Adulto , Pared Torácica/cirugía , Titanio , Mallas Quirúrgicas , Neoplasias Torácicas/cirugía , Sarcoma/patología , Politetrafluoroetileno
12.
Skin Res Technol ; 30(4): e13687, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38566505

RESUMEN

BACKGROUND: The physical appearance of an individual plays a primary role as it influences the opinion of the viewer. For this reason, orthodontic therapy to improve perceived aesthetics is in high demand among patients. This factor, combined with the increase in the number of non-invasive facial aesthetic treatments, has led to the need to understand potential risk factors in the application of medical devices to the perioral skin in patients with fixed orthodontic appliances. The aim of this study was to evaluate in vitro heating of the orthodontic bracket following electromagnetic fields and negative pressure (V-EMF) used as an anti-aging treatment. METHODS: Two different types of titanium alloy wires, one made of "beta-Titanium" alloy and the other "Ni-Ti" (DW Lingual Systems GmbH-Bad Essen-Germany) were used. The orthodontic wires and brackets mounted on a resin mouth were covered with porcine muscle tissue, then subjected to anti-aging therapy with a Bi-one LifeTouchTherapy medical device (Expo Italia Srl-Florence-Italy) which generates a combination of vacuum and electromagnetic fields (V-EMF) already adopted for antiaging therapy. During administration of the therapy, the orthodontic brackets and porcine tissue were thermally monitored using a Wavetek Materman TMD90 thermal probe (Willtek Communications GmbH-Germany). In total 20 orthodontic mouths were used, 10 with Beta Titanium wires and 10 with Nickel Titanium wires. RESULTS: A temperature increase of about 1°C was recorded in each group. The outcome of the present research shows that the absolute temperatures measured on orthodontic appliances, which, despite having a slightly different curve, both show an increase in temperature of 1.1°C at the end of the session, thus falling well within the safety range of 2°C as specified by the standard CENELEC EN 45502-1. Therefore, V-EMF therapy can be considered safe for the entire dental system and for metal prostheses, which tend to heat up at most as much as biological tissue (+0.9°C/1.1°C vs. 1.1°C/1.1°C). CONCLUSION: In conclusion, anti-aging therapy with V-EMF causes a thermal increase on orthodontic brackets that is not harmful to pulp health.


Asunto(s)
Campos Electromagnéticos , Níquel , Titanio , Humanos , Animales , Porcinos , Vacio , Calefacción , Alambres para Ortodoncia , Aleaciones , Ensayo de Materiales
13.
Shanghai Kou Qiang Yi Xue ; 33(1): 54-58, 2024 Feb.
Artículo en Chino | MEDLINE | ID: mdl-38583025

RESUMEN

PURPOSE: To compare the forming ability of four kinds of nickel-titanium instrument preparation resin for simulated curved root canal. METHODS: A total of 40 single bend resin simulated root canals were randomly divided into 4 groups with 10 in each group. Four kinds of nickel-titanium instruments (ProTaper, HyFlex EDM, WaveOne Gold and Reciproc Blue) were used for root canal preparation, and divided into group A, group B, group C and group D. The preparation time of the four groups was compared, the root canal images before and after preparation were analyzed by computer image analysis software, and the changes of the preparation time, curvature and curvature radius of the four groups were recorded. With the root tip as the center of the circle, the radius of 1-10 mm was selected as concentric circle arcs. The detection points were overlapping root canal intersection points. The resin removal amount and center positioning force of the inner and outer walls of the root canal at different detection points were recorded. Statistical analysis was performed with SPSS 20.0 software package. RESULTS: The root canal preparation time in group A was significant longer than that in group B, C and D(P<0.05), but there was no significant difference in the curvature and curvature radius of the root canal among the four groups (P>0.05). The removal amount of resin from the root canal wall in group C was significant lower than that in group A, B and D (P<0.05) when the distance from the detection point to the apical foramina was 5, 6, 8, 9 and 10 mm, respectively. The removal amount of resin from the outer wall of the root canal in group C was significant lower than that in group A, B and D (P<0.05) when the distance from the detection point to the apical foramina was 5, 6, 7, 9 and 10 mm, respectively. The root tip offset of group A from the detection point to the apical hole of 1, 2, 3, 4, 6, 7, 8, 9 and 10 mm was significant greater than that of group B, C and D(P<0.05). CONCLUSIONS: Among the four instruments, ProTaper has the largest apical deviation, HyFlex EDM, WaveOne Gold and Reciproc Blue have better ability of root canal forming.


Asunto(s)
Cavidad Pulpar , Titanio , Níquel , Instrumentos Dentales , Preparación del Conducto Radicular/métodos , Diseño de Equipo
14.
J Mater Chem B ; 12(16): 4039-4052, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38591157

RESUMEN

Clear cell renal cell carcinoma (ccRCC) is a disease with high incidence and poor prognosis. The conventional treatment involves radiotherapy and chemotherapy, but chemotherapeutic agents are often associated with side effects, i.e., cytotoxicity to nontumor cells. Therefore, there is an urgent need for the development of novel therapeutic strategies for ccRCC. We synthesized spherical P/TiO2 nanoparticles (P/TiO2 NPs) by vaporization phosphorization (VP). X-ray photoelectron spectroscopy (XPS) and ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis DRS) analyses confirmed that the anatase TiO2 surface was successfully doped with phosphorus and produced a large number of oxygen vacancies (OV). Serving as a photosensitizer, P/TiO2 NPs not only extended the photoresponse range to the near-infrared II region (NIR II) but also introduced a donor energy level lower than the TiO2 conduction band, narrowing the band gap, which could facilitate the migration of photogenerated charges and trigger the synergistic treatment of photodynamic therapy (PDT) and photothermal therapy (PTT). During NIR irradiation in vitro, the P/TiO2 NPs generated local heat and various oxygen radicals, including 1O2, ˙O2-, H2O2, and ˙OH, which damaged the ccRCC cells. In vivo, administration of the P/TiO2 NPs + NIR reduced the tumor volume by 80%, and had the potential to inhibit tumor metastasis by suppressing intratumor neoangiogenesis. The P/TiO2 NPs showed superior safety and efficacy relative to the conventional chemotherapeutic agent used in ccRCC treatment. This study introduced an innovative paradigm for renal cancer treatment, highlighting the potential of P/TiO2 NPs as safe and effective nanomaterials and presenting a compelling new option for clinical applications in anticancer therapy.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Nanocompuestos , Fósforo , Fotoquimioterapia , Terapia Fototérmica , Titanio , Titanio/química , Titanio/farmacología , Fósforo/química , Humanos , Animales , Nanocompuestos/química , Neoplasias Renales/tratamiento farmacológico , Neoplasias Renales/patología , Neoplasias Renales/terapia , Ratones , Carcinoma de Células Renales/tratamiento farmacológico , Carcinoma de Células Renales/patología , Carcinoma de Células Renales/terapia , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/síntesis química , Antineoplásicos/química , Antineoplásicos/farmacología , Antineoplásicos/síntesis química , Supervivencia Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Ratones Desnudos , Ratones Endogámicos BALB C , Ensayos de Selección de Medicamentos Antitumorales , Tamaño de la Partícula , Línea Celular Tumoral
15.
Clin Biomech (Bristol, Avon) ; 114: 106239, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38599132

RESUMEN

BACKGROUND: The application of expandable titanium-cages has gained widespread use in vertebral body replacement for indications such as burst fractures, tumors and infectious destruction. However, torque forces necessary for a satisfactory expansion of these implants and for subsidence of them into the adjacent vertebrae are unknown within the osteoporotic spine. METHODS: Six fresh-frozen human, osteoporotic, lumbar spines were dorsally instrumented with titanium implants (L2-L4) and a partial corpectomy of L3 was performed. An expandable titanium-cage was inserted ventrally and expanded by both residents and senior surgeons until fixation was deemed sufficient, based on haptic feedback. Torque forces for expansion were measured in Nm. Expansion was then continued until cage subsidence occurred. Torque forces necessary for subsidence were recorded. Strain of the dorsal rods during expansion was measured with strain gauges. FINDINGS: The mean torque force for fixation of cages was 1.17 Nm (0.9 Nm for residents, 1.4 Nm for senior surgeons, p = .06). The mean torque force for subsidence of cages was 3.1 Nm (p = .005). Mean peak strain of the dorsal rods was 970 µm/m during expansion and 1792 µm/m at subsidence of cages (p = .004). INTERPRETATION: The use of expandable titanium-cages for vertebral body replacement seems to be a primarily safe procedure even within the osteoporotic spine as torque forces required for subsidence of cages are nearly three times higher than those needed for fixation. Most of the expansion load is absorbed by straining of the dorsal instrumentation. Rod materials other than titanium may alter the torque forces found in this study.


Asunto(s)
Fusión Vertebral , Titanio , Humanos , Cuerpo Vertebral , Torque , Vértebras Lumbares/cirugía , Prótesis e Implantes
16.
Int J Pediatr Otorhinolaryngol ; 179: 111938, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38579403

RESUMEN

INTRODUCTION: Endoscopic ossicular chain reconstruction (OCR) in adults has demonstrated equivalent outcomes to the traditional microscopic approach. Less data exist on endoscopic OCR outcomes in children, who have unique considerations including a smaller transcanal corridor and variable pathology. The purpose of this study was to investigate surgical and audiometric outcomes in children undergoing fully endoscopic and endoscopic-assisted OCR in both the short and long-term. METHODS: Retrospective review of all children (<17 years) who underwent endoscopic OCR at one tertiary care center between 2017 and 2021. Children undergoing primary and revision endoscopic OCR with either partial (PORP) and total ossicular reconstruction prostheses (TORP) were included. Children undergoing surgery for juvenile otosclerosis or congenital stapes fixation, or any child receiving a stapes prosthesis were excluded. Primary outcome measures were post-operative change in 4 frequency (500 Hz, 1, 2, 4 KHz) air conduction pure tone average (AC PTA) and change in air-bone gap (ABG). Secondary measures included need for readmission and/or revision surgery, complication rate, and surgery duration. RESULTS: Seventeen patients met inclusion criteria. Average age was 11.3 years (range, 5-17 years); 14 were male. A variety of fixed length, titanium total and partial prostheses were used. The most common prosthesis length was 2 mm (range 2-5 mm), and there were no intra- or perioperative complications. Mean long-term follow-up was 2.6 years. Most common pathology was congenital cholesteatoma (11/17, 64%), followed by chronic otitis media with tympanic membrane perforation (5/17, 29.4%), and extruded prosthesis (1/17, 5.9%). Intraoperatively, the most common finding was incus erosion (10/17, 58.8%), followed by malleus erosion (6/17, 35.3%), stapes erosion (4/17, 23.5%), and stapes absence (4/17, 23.5%). Eight children (47%) were reconstructed with PORPs, and 9 children (52.9%) were reconstructed with TORPs. Average ABG improved from 36.8 dB preoperatively to 19.9 dB postoperatively in the short-term and remained stable at 19.5 dB in the long-term. Average short-term ABG improvement was 4.2 dB for PORPs and 18 dB for TORPs. In the long-term, average ABG improved by 2.3 dB in PORPs and 13.4 dB in TORPs. PORPs had higher rates of ABG closure and lower AC PTAs than TORPs in the long-term. DISCUSSION: Endoscopic ossiculoplasty is a viable option in children presenting with ossicular erosion from various causes. Audiometric improvement following endoscopic partial and total ossicular reconstruction remains stable over time, with a preference towards partial in the long-term, and mirrors published outcomes for microscopic surgery.


Asunto(s)
Prótesis Osicular , Reemplazo Osicular , Adulto , Humanos , Masculino , Niño , Femenino , Titanio , Implantación de Prótesis , Oído Medio , Estudios Retrospectivos , Resultado del Tratamiento
17.
BMC Musculoskelet Disord ; 25(1): 259, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38566097

RESUMEN

BACKGROUND: Modular neck femoral stems are advantageous because they can accurately restore the ideal hip geometry using various options in terms of offset, length, and version. However, there are concerns regarding junctional problems. Despite several reports on such issues, there is a lack of study on mid- to long-term results of these stems. The current study evaluated the mid-term results of patients who underwent primary total hip arthroplasty using a titanium-titanium (Ti-Ti) modular neck femoral stem. METHODS: In total, data on 47 hips (42 patients) that could be followed-up for ≥ 5 years after primary total hip arthroplasty using the Ti-Ti modular neck femoral stem from 2011 to 2015 were reviewed. There were 22 male and 20 female patients, and their mean age was 56.3 (range: 31-76) years. The mean follow-up period was 8 (range: 5-12) years. Functional and radiological outcomes, complications, and reoperations were investigated. In addition, we conducted a comparative analysis of the outcomes between those who underwent surgery using the Ti-Ti modular neck femoral stem and 41 hips (35 patients, 19 males and 16 females) that underwent primary total hip arthroplasty using nonmodular femoral stems as a control. RESULTS: In all Ti-Ti cases, the mean Harris Hip Scores were 50.6 (range: 6-59) preoperatively and 92.7 (range: 78-99) at the last follow-up (P < 0.001). Regarding the neck component's modularity, straight neck components were used in all Ti-Ti cases, and an anteverted or a retroverted neck was not used in any case. Stem revision was performed in one hip due to aseptic loosening. One hip underwent open reduction and internal fixation due to periprosthetic fracture without stem loosening. There were no cases of osteolysis and periprosthetic joint infection and clinically detectable junctional problems. The stem survival rate, with any stem revision as the endpoint, at 12 years was 96.6%. No significant difference was observed in the functional and radiological outcomes beween the Ti-Ti and nonmodular groups. CONCLUSIONS: The Ti-Ti modular neck femoral stem had comparable results with broadly used nonmodular femoral stems; hence, it can be a reliable option in primary total hip arthroplasty. However, in terms of the modularity itself of the modular neck femoral stem, whether the modular neck femoral stem is useful in uncomplicated primary total hip arthroplasty is unclear.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Prótesis de Cadera , Humanos , Masculino , Femenino , Persona de Mediana Edad , Artroplastia de Reemplazo de Cadera/efectos adversos , Artroplastia de Reemplazo de Cadera/métodos , Titanio , Diseño de Prótesis , Estudios Retrospectivos , Reoperación , Estudios de Seguimiento , Falla de Prótesis
18.
PLoS One ; 19(4): e0299896, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38568900

RESUMEN

The objective was to evaluate the effect of glide path and coronal flaring on the dentin volume removal and percentage of touched walls in curved canals using two heat-treated rotary files. The mesiobuccal canal of forty-eight, randomly selected, extracted mandibular molars was divided into two groups of 24 each, according to the type of instrument used (RACE EVO and EdgeSequel rotary files). Each group was further divided into three subgroups; Group (A): Control using one file shaped to 04/30, Group (B) with a glide path (EdgeGlidePath (EGP)), and Group (C): with a glide path and coronal flaring (EGP and EdgeTaper Platinum (ETP) SX file respectively). The root canals were then instrumented using the assigned instruments. The assessment was carried out using micro-CT. The comparison of the mean values of the tested groups about dentin volume removal and percentage of untouched walls did not reach statistical significance (p<0.05). Glide path and coronal flaring had an insignificant effect on the dentin volume removal and percentage of untouched walls in curved canals.


Asunto(s)
Calor , Níquel , Preparación del Conducto Radicular , Microtomografía por Rayos X/métodos , Preparación del Conducto Radicular/métodos , Aleaciones , Titanio , Cavidad Pulpar/diagnóstico por imagen , Cavidad Pulpar/cirugía , Diseño de Equipo
19.
Sci Rep ; 14(1): 7715, 2024 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-38565575

RESUMEN

Titanium dioxide nanoparticles (TiO2-NPs) have found wide applications in medical and industrial fields. However, the toxic effect of various tissues is still under study. In this study, we evaluated the toxic effect of TiO2-NP on stomach, liver, and kidney tissues and the amelioration effect of clove oil nanoemulsion (CLV-NE) against DNA damage, oxidative stress, pathological changes, and the apoptotic effect of TiO2-NPs. Four groups of male mice were subjected to oral treatment for five consecutive days including, the control group, the group treated with TiO2-NPs (50 mg/kg), the group treated with (CLV-NE) (5% of the MTD), and the group treated with TiO2-NPs plus CLV-NE. The results revealed that the treatment with TiO2-NPs significantly caused DNA damage in the liver, stomach, and kidney tissues due to increased ROS as indicated by the reduction of the antioxidant activity of SOD and Gpx and increased MDA level. Further, abnormal histological signs and apoptotic effect confirmed by the significant elevation of p53 expression were reported after TiO2-NPs administration. The present data reported a significant improvement in the previous parameters after treatment with CLV-NE. These results showed the collaborative effect of the oils and the extra role of nanoemulsion in enhancing antioxidant effectiveness that enhances its disperse-ability and further promotes its controlled release. One could conclude that CLV-NE is safe and can be used as a powerful antioxidative agent to assess the toxic effects of the acute use of TiO2-NPs.


Asunto(s)
Nanopartículas del Metal , Nanopartículas , Ratones , Masculino , Animales , Aceite de Clavo/toxicidad , Nanopartículas/toxicidad , Antioxidantes/farmacología , Antioxidantes/metabolismo , Estrés Oxidativo , Titanio/toxicidad , Daño del ADN
20.
BMC Vet Res ; 20(1): 127, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38561720

RESUMEN

BACKGROUND: Pseudomonas putida is a pathogenic bacterium that induces great losses in fishes, including Nile tilapia (Oreochromis niloticus). Currently, the application of nanomaterials in aquaculture practices has gained more success as it endows promising results in therapies compared to traditional protocols. OBJECTIVE: Therefore, the current perspective is considered the first report to assess the anti-bacterial efficacy of titanium dioxide nanogel (TDNG) against Pseudomonas putida (P. putida) in Nile tilapia. METHODS: The fish (n = 200; average body weight: 47.50±1.32 g) were allocated into four random groups (control, TDNG, P. putida, and TDNG + P. putida), where 0.9 mg/L of TDNG was applied as bath treatment for ten days. RESULTS: Outcomes revealed that P. putida infection caused ethological alterations (surfacing, abnormal movement, and aggression) and depression of immune-antioxidant variables (complement 3, lysozyme activity, total antioxidant capacity, superoxide dismutase, and reduced glutathione content). Additionally, a substantial elevation in hepatorenal biomarkers (aspartate and alanine aminotransferases and creatinine) with clear histopathological changes and immuno-histochemical alterations (very weak BCL-2 and potent caspase-3 immuno-expressions) were seen. Surprisingly, treating P. putida-infected fish with TDNG improved these variables and obvious restoration of the tissue architectures. CONCLUSION: Overall, this report encompasses the key role of TDNG as an anti-bacterial agent for controlling P. putida infection and improving the health status of Nile tilapia.


Asunto(s)
Cíclidos , Enfermedades de los Peces , Polietilenglicoles , Polietileneimina , Pseudomonas putida , Titanio , Animales , Antioxidantes , Nanogeles , Dieta , Suplementos Dietéticos , Alimentación Animal/análisis , Enfermedades de los Peces/tratamiento farmacológico , Enfermedades de los Peces/microbiología
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