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1.
Int J Nanomedicine ; 19: 2995-3007, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38559446

RESUMO

Background: In the past decades, antimicrobial resistance (AMR) has been a major threat to global public health. Long-term, chronic otitis media is becoming more challenging to treat, thus the novel antibiotic alternative agents are much needed. Methods: ZnO@TiO2@AMP (ATZ NPs) were synthesized through a solvothermal method and subjected to comprehensive characterization. The in vitro and in vivo antibacterial effect and biocompatibility of ATZ NPs were evaluated. For the antibacterial mechanism exploration, we utilized the Electron Paramagnetic Resonance (EPR) Spectrometer to detect and analyze the hydroxyl radicals produced by ATZ NPs. Results: ATZ NPs exhibited a spherical structure of 99.85 nm, the drug-loading rate for ZnO was 20.73%, and AMP within ATZ NPs was 41.86%. Notably, the Minimum Inhibitory Concentration (MIC) value of ATZ NPs against Staphylococcus aureus (S. aureus), methicillin-resistant Staphylococcus aureus (MRSA), and Streptococcus pneumoniae (S. pneumoniae) were 10 µg/mL, and Minimum Bactericidal Concentration (MBC) value of ATZ NPs against S. aureus, and S. pneumoniae were 50 µg/mL. In comparison to the model group, the treatment of otitis media with ATZ NPs significantly reduces inflammatory exudation in the middle ear cavity, with no observable damage to the tympanic membrane. Both in vivo and in vitro toxicity tests indicating the good biocompatibility of ATZ NPs. Moreover, EPR spectroscopy results highlighted the superior ability of ATZ NPs to generate hydroxyl radicals (·OH) compared to ZnO NPs. Conclusion: ATZ NPs exhibited remarkable antibacterial properties both in vivo and in vitro. This innovative application of advanced ATZ NPs, bringing great promise for the treatment of otitis media.


Assuntos
Nanopartículas Metálicas , Staphylococcus aureus Resistente à Meticilina , Otite Média , Infecções Estafilocócicas , Óxido de Zinco , Humanos , Staphylococcus aureus , Radical Hidroxila , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Antibacterianos/farmacologia , Antibacterianos/química , Otite Média/tratamento farmacológico , Testes de Sensibilidade Microbiana , Nanopartículas Metálicas/química
2.
Artigo em Inglês | MEDLINE | ID: mdl-38567929

RESUMO

OBJECTIVES: This RCT aimed to compare zirconia and titanium dental implants in the maxillary premolar region. The comparison was based on marginal bone level (MBL) changes, clinical parameters, aesthetic outcomes, and patient related outcome measures (PROMs) 1 year after prosthetic loading. MATERIALS AND METHODS: Fifty patients were randomly assigned to receive either a zirconia (ZrO2, n = 25) implant or a titanium (Ti, n = 25) bone-level implant. Implants were provided with a lithium disilicate crown 3 months after placement. Follow-up was at 1 month and after 1 year. The primary outcome pertained to changes in MBL. Reported secondary outcomes consisted of implant survival, peri-implant tissue health, aesthetics, and PROMs. RESULTS: Mean MBL change after 1 year was 0.01 mm (SD = 0.45; min = 0.72, max = 0.86) for ZrO2 and -0.09 mm (SD = 0.34; min = 0.53, max = -1.06) for Ti (p = .439). Scores for the other clinical outcome parameters and PROMs were generally favorable, with no significant differences. However, significant differences were found for the aesthetic outcomes regarding two criteria: (a) level of facial mucosa (p = .022), in favor of Ti, and (b) root convexity/soft tissue color and texture (p = .005) in favor of ZrO2. CONCLUSION AND CLINICAL IMPLICATIONS: The ZrO2 and Ti implant types used in this study, replacing a single missing maxillary premolar, show a comparable outcome in terms of MBL change after 1 year. Clinical and aesthetic parameters, as well as PROMs, are favorable and similar between both implant types after 1 year of prosthetic loading. These short-term study results suggest that both are suitable for clinical use.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38568410

RESUMO

Titanium dioxide (TiO2) is a well-known material for its biomedical applications, among which its implementation as a photosensitizer in photodynamic therapy has attracted considerable interest due to its photocatalytic properties, biocompatibility, high chemical stability, and low toxicity. However, the photoactivation of TiO2 requires ultraviolet light, which may lead to cell mutation and consequently cancer. To address these challenges, recent research has focused on the incorporation of metal dopants into the TiO2 lattice to shift the band gap to lower energies by introducing allowed energy states within the band gap, thus ensuring the harnessing of visible light. This study presents the synthesis, characterization, and application of TiO2 nanoparticles (NPs) in their undoped, doped, and co-doped forms for antimicrobial photodynamic therapy (APDT) against Candida albicans. Blue light with a wavelength of 450 nm was used, with doses ranging from 20 to 60 J/cm2 and an NP concentration of 500 µg/ml. It was observed that doping TiO2 with Cu, Fe, Ag ions, and co-doping Cu:Fe into the TiO2 nanostructure enhanced the visible light photoactivity of TiO2 NPs. Experimental studies were done to investigate the effects of different ions doped into the TiO2 crystal lattice on their structural, optical, morphological, and chemical composition for APDT applications. In particular, Ag-doped TiO2 emerged as the best candidate, achieving 90-100% eradication of C. albicans.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38564013

RESUMO

INTRODUCTION: Distal femur fractures account for 3-6% of all femur fractures. Internal fixation of most distal femur fractures with an anatomic lateral locking plate should permit some motion at the metaphyseal portion of the fracture when secondary bone healing is planned by the operating surgeon. While several studies have been performed evaluating union rates for distal femur fractures with stainless steel and titanium plates, the timing of callus formation between stainless steel and titanium implants used as bridge plates for distal femur fractures (AO/OTA 33-A and -C) has been investigated to a lesser extent. We hypothesize that callus will be visualized earlier with post-operative radiographs with titanium versus stainless steel bridge plates. METHODS: We retrospectively reviewed a consecutive cohort of patients over 18 years of age with acute AO/OTA 33-A and 33-C fracture patterns treated with an isolated stainless steel or titanium lateral bridge plate within 4 weeks of injury by a single fellowship-trained orthopedic trauma surgeon from 2011 to 2020 at one academic Level 1 trauma center. An independent, fellowship-trained orthopedic trauma attending surgeon reviewed anterior-posterior (AP) and lateral radiographs from every available post-operative clinic visit and graded them using the Modified Radiographic Score for Tibia (mRUST). RESULTS: Twenty-five subjects were included in the study with 10 with stainless steel and 15 with titanium plates. There were no significant differences in demographics between both groups, including age, sex, BMI, injury classification, open versus closed, mechanism, and laterality. Statistically significant increased mRUST scores, indicating increased callus formation, were seen on 12-week radiographs (8.4 vs. 11.9, p = 0.02) when titanium bridge plates were used. There were no statistically significant differences in mRUST scores at 6 or 24-weeks, but scores in the titanium group were higher in at every timepoint. DISCUSSION: In conclusion, we observed greater callus formation at 12 weeks after internal fixation of 33-A and 33-C distal femur fractures treated with titanium locked lateral distal femoral bridge plates compared to stainless steel plates. Our data suggest that titanium metallurgy may have quicker callus formation compared to stainless steel if an isolated, lateral locked bridge plate is chosen for distal femur fracture fixation.

5.
Sci Rep ; 14(1): 7715, 2024 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-38565575

RESUMO

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.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Camundongos , Masculino , Animais , Óleo de Cravo/toxicidade , Nanopartículas/toxicidade , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Estresse Oxidativo , Titânio/toxicidade , Dano ao DNA
6.
Cureus ; 16(3): e55456, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38571818

RESUMO

Background Varied surface coatings have been studied time and again in medical sciences. Whether general or dental, studying the performance of coatings aims to assess their potential to improve the durability and longevity of titanium implants, thereby advancing implant technology for enhanced patient outcomes. Various analytical techniques are utilized to assess the performance of the coating, providing insights into its effectiveness in preventing corrosion. The findings of this evaluation will contribute to our understanding of corrosion mitigation strategies for titanium implants and pave the way for the development of more durable implant materials. This article aims to evaluate the corrosion resistance of an innovative metal compound coating applied over titanium implants.  Materials and methods In this study, a total of 20 medical-grade, commercially pure titanium screws were collected. The dimensions of the titanium screws were 2mm x 7mm. Around 10 of these commercially pure titanium screw samples were used as the control group. Hafnium nitride (HfN) (0.1 M) was mixed with 100% ethanol and stirred using a glass rod for about 48 hours. Then 10 of the implant screw samples were immersed in the prepared sol and sintered at 400o C for two hours. The HfN-coated samples were then used as the test group. The corrosion resistance of both groups was tested using electrochemical impedance spectroscopy and potentiodynamic polarization studies. The Nyquist, Bode impedance, and Bode phase angle plots were obtained and studied.  Results Using the Stern-Geary equation, the corrosion current density was calculated. On analysis, these values indicated that the higher impedance in HfN-coated titanium screws showed higher mean corrosion potential (Ecorr = -0.452 V) and corrosion current density ( icorr = 0.0354 µA/cm2) than the uncoated titanium screws.  Conclusion It was concluded that the corrosion properties of HfN-coated titanium screws had higher impedance and consequently the highest corrosion resistance. This thereby provides a promising scope for further research of this novel metal coating for use in the biomedical sectors, specifically for dental implants.

7.
Food Chem ; 449: 139168, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38574521

RESUMO

A robust biocompatible solid-phase microextraction (SPME) fiber, so-called Ti/APTS/GA/CS, was prepared by chemical bonding of cross-linked glutaraldehyde-chitosan to the surface of a titanium wire using APTS. The fiber was applied for sampling of phytohormones in plant tissues, followed by HPLC-UV analysis. The structure and morphology of the fiber coating was investigated by FT-IR, SEM, EDX, XRD, and TGA techniques. A Box-Behnken design was implemented to optimize the experimental variables. The calibration graphs were linear over a wide linear range (0.5-200 µg L-1) with LODs over the range of 0.01-0.06 µg L-1. The intra-day and inter-day precisions were found to be 1.3-6.3% and 4.3-7.3%, respectively. The matrix effect values ranged from 86.5% to 111.7%, indicating that the complex sample matrices had an insignificant effect on the determination of phytohormones. The fiber was successfully employed for the direct-immersion SPME (DI-SPME-HPLC) analysis of the phytohormones in cucumber, tomato, date palm, and calendula samples.

8.
J Pharm Bioallied Sci ; 16(Suppl 1): S945-S947, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38595349

RESUMO

Objective: To compare the antibacterial and anti-adherent properties of conventional stainless steel (SS) orthodontic wires and surface-modified silver dioxide-coated and titanium oxide-coated SS orthodontic wires against Streptococcus sanguis causing gingivitis. Materials and Methods: The study used 60 orthodontic SS wire specimens, organized into six groups of ten each. The control group had uncoated wires, and the experimental group featured wires coated with silver dioxide and titanium oxide. Surface modification was done using DC sputtering, and microbiological tests assessed the antibacterial and anti-adherent properties of the AgO2- and TiO2-coated wires. Results: This study demonstrated the antibacterial effect against S. sanguis in orthodontic wires coated with the photocatalytic AgO2 and TiO2 compared to the uncoated wires. Also, this study demonstrated an anti-adherent effect in the AgO2- and TiO2-coated orthodontic wires. Moreover, the bacterial accumulation on orthodontic wires coated with AgO2 and TiO2 was lower compared to that on the uncoated wires. Conclusion: During orthodontic treatment, the formation of dental plaque can be prevented by coating the surface of stainless-steel orthodontic wires with photocatalytic AgO2 and TiO2. Compared to silver dioxide, the titanium oxide-coated SS orthodontic wires showed better antibacterial and anti-adherent properties.

9.
J Pharm Bioallied Sci ; 16(Suppl 1): S537-S539, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38595400

RESUMO

Background: Orthodontic treatment is commonly used to correct misaligned teeth and improve dental aesthetics and function. Archwires play a crucial role in this treatment by exerting forces on teeth, prompting them to shift into desired positions. Materials and Methods: For this experimental study, 60 participants requiring orthodontic treatment were selected and divided into three groups: Group A, treated with stainless steel archwires; Group B, treated with nickel-titanium archwires; and Group C, treated with beta-titanium archwires. Standardized orthodontic procedures were followed for all participants. The rate of tooth movement was measured over a period of 6 months using digital models and a calibrated measurement technique. Results: The study revealed notable differences in the rate of orthodontic tooth movement among the three groups. Group B (nickel-titanium archwires) demonstrated the highest mean rate of tooth movement, with an average of 1.5 mm per month. Group A (stainless steel archwires) exhibited a mean rate of 1.2 mm per month, while Group C (beta-titanium archwires) showed the lowest mean rate at 0.9 mm per month. Conclusion: In conclusion, this study highlights the varying efficacy of different archwire materials in accelerating orthodontic tooth movement. Nickel-titanium archwires exhibited the highest rate of tooth movement compared to stainless steel and beta-titanium archwires.

10.
J Pharm Bioallied Sci ; 16(Suppl 1): S247-S249, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38595517

RESUMO

Objective: This study's objective was to assess and contrast the performance of several plating techniques in the treatment of zygomaticomaxillary complex (ZMC) fractures. Group A (Microplate System), Group B (Titanium Mesh System), and Group C (Absorbable Plate System) plating systems were the ones that were studied. Materials and Methods: With 10 patients in each group, a retrospective analysis of 30 patients with ZMC fractures was done. The following information was gathered: fracture reduction, stable fixation, complications, and patient satisfaction. Analysis was done on patient-reported outcomes, surgical outcomes, and demographic factors. Results: Group B (Titanium Mesh System) came in second with rates of 70% and 80%, respectively, while Group A (Microplate System) showed the highest rates of fracture reduction (90%) and stable fixation (100%). For fracture reduction and stable fixation, Group C (Absorbable Plate System) demonstrated rates of 80% and 90%, respectively. For Groups A, B, and C, the complication rates were 20%, 30%, and 10%, respectively. For Groups A, B, and C, the patient satisfaction levels were 90%, 80%, and 70%, respectively. Conclusion: According to the results, the Microplate System (Group A) is better than the Titanium Mesh System (Group B) and the Absorbable Plate System (Group C) in terms of fracture reduction and stable fixation when treating ZMC fractures. All plating systems had acceptable complication rates, and overall patient satisfaction ratings were high. Fracture features and patient-specific considerations should be taken into account while making individualized treatment options.

11.
J Pharm Bioallied Sci ; 16(Suppl 1): S711-S713, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38595627

RESUMO

Background: Effective endodontic instrumentation aims to remove microorganisms, debris, and tissue from the root canal while maintaining dentinal integrity. This study compares dentinal defect incidence following canal preparation with different hand files, nickel-titanium rotary files, and reciprocating files. Materials and Methods: Eighty single-rooted mandibular premolars with mature apices were collected. Four groups (n = 20) were established based on canal patency establishment, canal preparation technique, irrigation solution, and final irrigation. After root sectioning at 3 mm, 6 mm, and 9 mm from the apex, slices were examined under a stereomicroscope, and dentinal defects were recorded. A second examiner reviewed the images. Results: The results showed significant difference of P = 0.031 among Hand files vs. Rotary ProTaper files: In Hand files vs. Reciprocating WaveOne files significant difference was P = 0.048, and for rotary ProTaper files vs. Reciprocating WaveOne files: No significant difference (P = 0.643). Dentinal defect counts were similar at 3 mm, 6 mm, and 9 mm. Statistically significant variation was observed between hand files and rotary files, as well as hand files and reciprocating files. Conclusion: Both rotary and reciprocating files showed a statistically significant increase in dentinal defect incidence compared to hand files. However, clinical implications should be considered cautiously. Instrumentation technique selection should be based on clinical context, operator experience, and patient factors. Further clinical studies are needed for validation.

12.
Artigo em Inglês | MEDLINE | ID: mdl-38594815

RESUMO

OBJECTIVES: Clinical data on all-ceramic screw-retained implant crowns (SICs) luted on titanium base abutments (TBAs) over more than 3 years are sparse. This study aimed to evaluate the clinical performance and potential risk factors for these restorations. MATERIALS AND METHODS: Analysis took place based on the medical patient-records of three dental offices. Implant survival and prosthetic complications over time were evaluated. The study included SICs in premolar and molar regions made from monolithic lithium disilicate ceramic (M_LiDi) or veneered zirconia (V_ZiO) luted on a TBA documented over an observation time of at least 3 years. Survival and complication rates were calculated and compared by a log-rank test. Cox-Regressions were used to check potential predictors for the survival (p < .05). RESULTS: Six hundred and one crowns out of 371 patients met the inclusion criteria and follow-up period was between 3.0 and 12.9 (mean: 6.4 (SD: 2.1)) years. Over time, six implants had to be removed and 16 restorations had to be refabricated. The estimated survival rates over 10 years were 93.5% for M_LiDi and 95.9% for V_ZiO and did not differ significantly among each other (p = .80). However, V_ZiO showed significantly higher complication rates (p = .003). Material selection, sex, age, and implant diameter did not affect the survival of investigated SICs but crown height influences significantly the survival rate (hazard ratio, HR = 1.26 (95%CI: 1.08, 1.49); p = .043). CONCLUSIONS: Screw-retained SICs luted on TBAs that were fabricated from monolithic lithium disilicate ceramic or veneered zirconia showed reliable and similar survival rates. Increasing crown heights reduced survival over the years.

13.
Artigo em Inglês | MEDLINE | ID: mdl-38598155

RESUMO

Formaldehyde (HCHO) is one of the primary indoor air pollutants, and efficiently eliminating it, especially at low concentrations, remains challenging. In this study, BiVO4-TiO2 catalyst was developed using ultrasonic blending technology for the photocatalytic oxidation of low-level indoor HCHO. The crystal structure, surface morphology, element distribution, and active oxidation species of the catalyst were examined using XRD, SEM, TEM, UV-Vis, EDS, and ESR techniques. Our results demonstrated that the BiVO4-TiO2 catalyst, prepared by ultrasonic blending, exhibited good oxidation performance and stability. The HCHO concentration reduced from 1.050 to 0.030 mg/m3 within 48 h, achieving a removal rate of 97.1%. The synergy between BiVO4 and TiO2 enhanced the efficiency of separating photogenerated carriers and minimized the likelihood of recombination between photogenerated electrons and holes. Additionally, this synergy significantly enhanced the presence of hydroxyl radicals (·OH) on the catalyst, resulting in an oxidation performance superior to that of either BiVO4 or TiO2. Our research offers valuable insights for the development of new photocatalysts to address HCHO pollution.

14.
Artigo em Inglês | MEDLINE | ID: mdl-38590232

RESUMO

Bruxism can be defined as the process of direct contact with teeth and dental materials with an involuntary jaw-tightening movement. In this process, teeth and dental materials can be exposed to various damage mechanisms. This study aims to realize the mechanism of bruxism with finite element analysis and in vitro rotating chewing movement analysis. Within the scope of the study, cp-Ti, Ti-5Zr, and Ti-5Ta materials were subjected to wear tests in the finite element analysis and in vitro rotating chewing movement method under the determined Bruxism chewing test conditions. Test specimens with cylindrical geometry were exposed to a direct every-contact wear mechanism for 30 s under 150 N bruxism chewing bite force. The bruxism chewing cycle continued for 300 min at a frequency of 2 Hz. Microanalysis of the wear surfaces of the samples after the experimental study was carried out with Scanning Electron Microscopy. The results obtained within the scope of this study showed that the Bruxism wear resistance increased by adding zirconium and tantalum to pure titanium material. This result shows that pure titanium material, which is known to have poor wear resistance, can be improved with Zr and Ta alloys. It is clinically important that the success rate in the treatment process increases with the increase in wear resistance. However, the micro-cracks observed in the microstructure may have occurred in the sub-surface, which is a show of the fatigue wear mechanism.

15.
Artigo em Inglês | MEDLINE | ID: mdl-38591734

RESUMO

OBJECTIVES: The aim of this narrative review was to explore the application of digital technologies (DT) for the simplification and improvement of bone augmentation procedures in advanced implant dentistry. MATERIAL AND METHODS: A search on electronic databases was performed to identify systematic reviews, meta-analyses, randomized and non-randomized controlled trials, prospective/retrospective case series, and case reports related to the application of DT in advanced implant dentistry. RESULTS: Seventy-nine articles were included. Potential fields of application of DT are the following: 1) the use of intra-oral scanners for the definition of soft tissue profile and the residual dentition; 2) the use of dental lab CAD (computer-aided design) software to create a digital wax-up replicating the ideal ridge and tooth morphology; 3) the matching of STL (Standard Triangulation Language) files with DICOM (DIgital COmmunication in Medicine) files from CBCTs with a dedicated software; 4) the production of stereolithographic 3D models reproducing the jaws and the bone defects; 5) the creation of surgical templates to guide implant placement and augmentation procedures; 6) the production of customized meshes for bone regeneration; and 7) the use of static or dynamic computer-aided implant placement. CONCLUSIONS: Results from this narrative review seem to demonstrate that the use of a partially or fully digital workflow can be successfully used also in advanced implant dentistry. However, the number of studies (in particular RCTs) focused on the use of a fully digital workflow in advanced implant dentistry is still limited and more studies are needed to properly evaluate the potentials of DT.

16.
Se Pu ; 42(4): 333-344, 2024 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-38566422

RESUMO

17ß-Estradiol (E2), an important endocrine hormone in the mammalian body, participates in the regulation of the physiological functions of the reproductive system, mammary glands, bone, and cardiovascular system, among others. Paradoxically, despite the physiological actions of endogenous E2 (0.2-1.0 nmol/L), numerous clinical and experimental studies have demonstrated that high-dose E2 treatment can cause tumor regression and exert pro-apoptotic actions in multiple cell types; however, the underlying mechanism remains undescribed. In particular, little information of the cellular processes responding to the lethality of E2 is available. In the present study, we attempted to characterize the cellular processes responding to high-dose (µmol/L) E2 treatment using quantitative phosphoproteomics to obtain a better understanding of the regulatory mechanism of E2-induced cell death. First, the cell phenotype induced by high-dose E2 was determined by performing Cell Counting Kit-8 assay (CCK8), cell cytotoxicity analysis by trypan blue staining, and microscopic imaging on HeLa cells treated with 1-10 µmol/L E2 or dimethyl sulfoxide (DMSO) for 1-3 d. E2 inhibited cell proliferation and induced cell death in a dose- and time-dependent manner. Compared with the DMSO-treated HeLa cells, the cells treated with 5 µmol/L E2 for 2 d demonstrated >74% growth inhibition and approximately 50% cell death. Thus, these cells were used for quantitative phosphoproteomic analysis. Next, a solid-phase extraction (SPE)-based immobilized titanium ion affinity chromatography (Ti4+-IMAC) phosphopeptide-enrichment method coupled with data-independent acquisition (DIA)-based quantitative proteomics was employed for the in-depth screening of high-dose E2-regulated phosphorylation sites to investigate the intracellular processes responding to high-dose E2 treatment. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) identified over 10000 phosphorylation sites regulated by E2 and DMSO in HeLa cells. In comparison with the DMSO-treated cells, the cells treated with 5 µmol/L E2 showed 537 upregulated phosphorylation sites and 387 downregulated phosphorylation sites, with a threshold of p<0.01 and |log2(fold change)|≥1. A total of 924 phosphorylation sites on 599 proteins were significantly regulated by high-dose E2, and these sites were subjected to enrichment analysis. In addition, 453 differently regulated phosphorylation sites on 325 proteins were identified only in the E2- or DMSO-treated cell samples. These phosphorylation sites may be phosphorylated or dephosphorylated in response to high-dose E2 stimulation and were subjected to parallel enrichment analyses. Taken together, 1218 phosphorylation sites on 741 proteins were significantly regulated by high-dose E2 treatment. The functional phosphoproteins in these two groups were then analyzed using Gene Ontology (GO) and Gene Set Enrichment Analysis (GSEA) to determine the biological processes in which they participate and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway database. Consistent with the cell-phenotype data, cell cycle-related proteins were highly enriched in the two groups of E2-regulated phosphoproteins (p<0.05), indicating that high-dose E2 treatment can regulate cell proliferation. In addition, E2-regulated phosphoproteins were highly enriched in the cellular processes of ribosome biogenesis, nucleocytoplasmic transport, and messenger ribonucleic acid (mRNA) processing/splicing (p<0.05), indicating that the activation of these processes may contribute to high-dose E2-induced cell death. These results further confirm that high-dose E2 treatment inhibits protein translation and induces cell death. Furthermore, the significant upregulation of multiple phosphorylation sites associated with epidermal growth factor receptor (EGFR) and mitogen-activated protein kinases (MAPKs) MAPK1, MAPK4, and MAPK14 by high-dose E2 indicates that the EGFR and MAPK signaling pathways are likely involved in the regulation of E2-induced cell death. These phosphorylation sites likely play vital roles in E2-induced cell death in HeLa cells. Overall, our phosphoproteomic data could be a valuable resource for uncovering the regulatory mechanisms of E2 in the micromolar range.


Assuntos
Dimetil Sulfóxido , Espectrometria de Massas em Tandem , Animais , Humanos , Cromatografia Líquida , Células HeLa , Estradiol/farmacologia , Fosfoproteínas/química , Fosfoproteínas/metabolismo , Receptores ErbB/metabolismo , Fosforilação , Mamíferos/metabolismo
17.
Sci Rep ; 14(1): 8045, 2024 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-38580674

RESUMO

Silver and titanium-silver nanoparticles have unique properties that make the textile industry progress through the high quality of textiles. Preparation of AgNPs and TiO2-Ag core-shell nanoparticles in different concentrations (0.01% and 0.1% OWF) and applying it to cotton fabrics (Giza 88 and Giza 94) by using succinic acid 5%/SHP as a cross-linking agent. Ultra-violet visible spectroscopy (UV-Vis), X-ray diffraction (XRD), dynamic light scattering (DLS), zeta potential, transmission electron microscopy (TEM), scanning electron microscopy/energy-dispersive X-ray (SEM-EDX) are tools for AgNPs and TiO2-AgNPs characterization and the treated cotton. The resulting AgNPs and TiO2-AgNPs were added to cotton fabrics at different concentrations. The antimicrobial activities, UV protection, self-cleaning, and the treated fabrics' mechanical characteristics were investigated. Silver nanoparticles and titanium dioxide-silver nanoparticles core-shell were prepared to be used in the treatment of cotton fabrics to improve their UV protection properties, self-cleaning, elongation and strength, as well as the antimicrobial activities to use the produced textiles for medical and laboratory uses and to increase protection for medical workers taking into account the spread of infection. The results demonstrated that a suitable distribution of prepared AgNPs supported the spherical form. Additionally, AgNPs and TiO2-AgNPs have both achieved stability, with values of (- 20.8 mV and - 30 mV, respectively). The synthesized nanoparticles spread and penetrated textiles' surfaces with efficiency. The findings demonstrated the superior UV protection value (UPF 50+) and self-cleaning capabilities of AgNPs and TiO2-AgNPs. In the treatment with 0.01% AgNPs and TiO2-AgNPs, the tensile strength dropped, but the mechanical characteristics were enhanced by raising the concentration to 0.1%. The results of this investigation demonstrated that the cotton fabric treated with TiO2-AgNPs exhibited superior general characteristics when compared to the sample treated only with AgNPs.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Humanos , Prata/química , Fibra de Algodão , Ácido Succínico , Nanopartículas Metálicas/química , Têxteis , Antibacterianos/farmacologia , Antibacterianos/química
18.
J Dent ; 145: 104977, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38582434

RESUMO

OBJECTIVE: This study compared the protective effect of an experimental TiF4/Chitosan toothpaste with a commercial toothpaste on the prevention of erosive tooth wear (ETW) in situ. METHODS: Fifteen subjects took part in this crossover and double-blind study, in which they wore a palatal appliance containing 4 bovine enamel and 4 dentin in 3 phases (5 days each). Half of the samples were subjected to erosive challenges (90 s in 0.1 % citric acid, pH 2.5, 4 times/day), and the other half to erosive plus abrasive challenges (15 s plus 45 s of contact, 2 times/day). The phases corresponded to the application of the different toothpastes: 1) TiF4 (1400 ppm F-) plus Chitosan, 2) Elmex®, Erosion Protection (1400 ppm F-, Chitosan), and 3) Placebo (negative control). Tooth wear was measured using contact profilometry (µm) and submitted to two-way RM ANOVA/Tukey test (p < 0.05). RESULTS: No significant differences were detected between the experimental and commercial toothpastes, regardless of the challenge on both tissues. Both significantly reduce ETW compared to negative control (p < 0.0006). Tooth wear was increased by brushing only on eroded enamel (p < 0.01), but not on dentin (p = 0.6085). TiF4/Chitosan [erosion 2.98 ± 1.12 µm vs. erosion and abrasion 3.12 ± 1.33 µm] and Elmex® toothpastes [erosion 2.35 ± 0.93 µm vs. erosion and abrasion 2.98 ± 1.0 µm] minimized the impact of brushing compared to placebo on enamel [erosion 4.62 ± 1.48 µm vs. erosion and abrasion 5.15 ± 1.50 µm]. CONCLUSIONS: TiF4 plus chitosan toothpastes showed to be effective in minimizing the ETW as the commercial toothpaste is in situ. CLINICAL RELEVANCE: The experimental toothpaste has similar effect against ETW compared to the commercial toothpaste. Considering the increased ETW prevalence worldwide, this result supports clinical trials and a possible application of this experimental anti-erosive toothpaste in the future.

19.
J Nanobiotechnology ; 22(1): 158, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589901

RESUMO

In the context of wound healing and tissue regeneration, precise control of cell migration direction is deemed crucial. To address this challenge, polydimethylsiloxane (PDMS) platforms with patterned 10 nm thick TiOx in arrowhead shape were designed and fabricated. Remarkably, without tall sidewall constraints, MC3T3-E1 cells seeded on these platforms were constrained to migrate along the tips of the arrowheads, as the cells were guided by the asymmetrical arrowhead tips which provided large contact areas. To the best of our knowledge, this is the first study demonstrating the use of thin TiOx arrowhead pattern in combination with a cell-repellent PDMS surface to provide guided cell migration unidirectionally without tall sidewall constraints. Additionally, high-resolution fluorescence imaging revealed that the asymmetrical distribution of focal adhesions, triggered by the patterned TiOx arrowheads with arm lengths of 10, 20, and 35 µm, promoted cell adhesion and protrusion along the arrowhead tip direction, resulting in unidirectional cell migration. These findings have important implications for the design of biointerfaces with ultrathin patterns to precisely control cell migration. Furthermore, microelectrodes were integrated with the patterned TiOx arrowheads to enable dynamic monitoring of cell migration using impedance measurement. This microfluidic device integrated with thin layer of guiding pattern and microelectrodes allows simultaneous control of directional cell migration and characterization of the cell movement of individual MC3T3-E1 cells, offering great potential for the development of biosensors for single-cell monitoring.


Assuntos
Dimetilpolisiloxanos , Adesões Focais , Adesão Celular , Movimento Celular
20.
Materials (Basel) ; 17(3)2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38591474

RESUMO

The hot deformation behavior of titanium matrix composites plays a crucial role in determining the performance of the formed components. Therefore, it is significant to establish an accurate constitutive relationship between material deformation parameters and flow stress. In this study, hot compression experiments were conducted on a (2.5 vol%TiB + 2.5 vol%TiC)/TC4. The experiments were performed under temperatures ranging from 1013.15 to 1133.15 K and strain rates ranging from 0.001 to 0.1 s-1. Based on the stress-strain data obtained from the experiment, the constitutive models were established by using the Arrhenius model and the BP neural network algorithm, respectively. Considering the relationship between strain rate, hot working temperature, and flow stress, a comparative analysis was conducted to evaluate the prediction accuracy of two different constitutive models. The research results indicate that the flow stress of (2.5 vol%TiB + 2.5 vol%TiC)/TC4 increases with decreasing temperature and increasing strain rate, and the stress-strain curve shows obvious work hardening and softening behaviors. Both the Arrhenius model and the BP neural network algorithm are effective in predicting the hot compression flow stress of (2.5 vol%TiB + 2.5 vol%TiC)/TC4, but the average relative error and root mean square error of the BP neural network algorithm are smaller and the correlation coefficient is higher, thus possessing higher accuracy and reliability.

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