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1.
Science ; 384(6697): 781-785, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38753795

RESUMO

Colloidal self-assembly allows rational design of structures on the micrometer and submicrometer scale. One architecture that can generate complete three-dimensional photonic bandgaps is the diamond cubic lattice, which has remained difficult to realize at length scales comparable with the wavelength of visible or ultraviolet light. In this work, we demonstrate three-dimensional photonic crystals self-assembled from DNA origami that act as precisely programmable patchy colloids. Our DNA-based nanoscale tetrapods crystallize into a rod-connected diamond cubic lattice with a periodicity of 170 nanometers. This structure serves as a scaffold for atomic-layer deposition of high-refractive index materials such as titanium dioxide, yielding a tunable photonic bandgap in the near-ultraviolet.


Assuntos
DNA , Fótons , Titânio , DNA/química , Titânio/química , Cristalização , Diamante/química , Nanoestruturas/química , Coloides/química , Conformação de Ácido Nucleico
2.
Sensors (Basel) ; 24(8)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38676026

RESUMO

This work presents a novel multielectrode array (MEA) to quantitatively assess the dose enhancement factor (DEF) produced in a medium by embedded nanoparticles. The MEA has 16 nanocrystalline diamond electrodes (in a cell-culture well), and a single-crystal diamond divided into four quadrants for X-ray dosimetry. DEF was assessed in water solutions with up to a 1000 µg/mL concentration of silver, platinum, and gold nanoparticles. The X-ray detectors showed a linear response to radiation dose (r2 ≥ 0.9999). Overall, platinum and gold nanoparticles produced a dose enhancement in the medium (maximum of 1.9 and 3.1, respectively), while silver nanoparticles produced a shielding effect (maximum of 37%), lowering the dose in the medium. This work shows that the novel MEA can be a useful tool in the quantitative assessment of radiation dose enhancement due to nanoparticles. Together with its suitability for cells' exocytosis studies, it proves to be a highly versatile device for several applications.


Assuntos
Diamante , Eletrodos , Ouro , Nanopartículas Metálicas , Diamante/química , Nanopartículas Metálicas/química , Ouro/química , Prata/química , Platina/química , Doses de Radiação , Humanos , Raios X , Nanopartículas/química
3.
Commun Biol ; 7(1): 318, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38480800

RESUMO

Diamond particles have recently emerged as novel agents in cellular studies because of their superb biocompatibility. Their unique characteristics, including small size and the presence of fluorescent color centers, stimulate many important applications. However, the mechanism of interaction between cells and diamond particles-uptake, transport, and final localization within cells-is not yet fully understood. Herein, we show a novel, to the best of our knowledge, cell behavior wherein cells actively target and uptake diamond particles rather than latex beads from their surroundings, followed by their active transport within cells. Furthermore, we demonstrate that myosin-X is involved in cell-particle interaction, while myosin-II does not participate in particle uptake and transport. These results can have important implications for drug delivery and improve sensing methods that use diamond particles.


Assuntos
Corantes , Diamante , Transporte Biológico , Transporte Biológico Ativo , Miosinas
4.
Chemosphere ; 355: 141763, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38522672

RESUMO

The fluoroquinolones ciprofloxacin, danofloxacin, enoxacin, levofloxacin and lomefloxacin, occur in water bodies worldwide and therefore pose a threat to the aquatic environment. Advanced purification procedures, such as electrochemical oxidation, may act as a remedy since they contribute to eliminating contaminants and prevent micropollutants from entering open water bodies. By electrochemical treatment in a micro-flow reactor equipped with a boron-doped diamond (BDD) electrode, the fluoroquinolones were efficiently degraded. A total of 15 new products were identified using high-performance high-resolution chromatography coupled with high-resolution multifragmentation mass spectrometry. The ecotoxicity of the emerging transformation products was estimated through in silico quantitative structure activity relationship analysis. Almost all transformation products were predicted less ecotoxic than the initial compounds. The fluoroquinolone degradation followed three major mechanisms depending on the voltage during the electrochemical oxidation. At approximately 1 V, the reactions started with the elimination of molecular hydrogen from the piperazine moiety. At approx. 1.25 V, methyl and methylene groups were eliminated. At 1.5 V, hydroxyl radicals, generated at the BDD electrode, led to substitution at the piperazine ring. This novel finding of the three reactions depending on voltage contributes to the mechanistic understanding of electrochemical oxidation as potential remedy against fluoroquinolones in the aquatic environment.


Assuntos
Ciprofloxacina , Poluentes Químicos da Água , Ciprofloxacina/química , Levofloxacino/análise , Enoxacino/análise , Diamante/química , Fluoroquinolonas/análise , Piperazina , Oxirredução , Eletrodos , Água , Poluentes Químicos da Água/análise
5.
Nagoya J Med Sci ; 86(1): 142-148, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38505725

RESUMO

Catheter ablation therapy for persistent atrial fibrillation (PeAF) is both difficult and has limited outcomes. The mechanisms underlying the development and persistence of atrial fibrillation (AF) are not fully understood; therefore, ablation strategies are diverse. A 45-year-old man was referred to our hospital for persistent atrial fibrillation to undergo radiofrequency catheter insertion (RFCA). In the first session we conducted pulmonary vein isolation and additional linear ablation, including that of the roof line and posterior inferior line (posterior box lesion) as the stepwise ablation. However, AF was recurred in six months, therefore he was readmitted for second session ablation preoperative 3D computed tomography (CT) scan for drug-refractory PeAF was performed. The additional isolation of the left superior pulmonary vein and potential drivers of AF by mapping wavefront propagation using multipolar catheters by CARTOFINDER (Biosense Webster, Inc, Diamond Bar, CA, USA) was conducted. However, AF did not terminate. Tomography revealed that the left atrial (LA) diverticulum (LAD) was found uniquely. Electrophysiological findings showed focal firing of the myocardial sleeve and LA diverticulum by an approach for defragmented potentials by re-visiting in interval confidence level (ICL) mode included in the electroanatomical mapping system (CARTO 3, Biosense Webster, Inc, Diamond Bar, CA, USA) and the ablation by encircling this site finally made AF terminate. The AF has not recurred for more than 12 months without the use of antiarrhythmic drugs. This case report suggests that additional ablation around substrates in LAD may be effective for treating refractory AF.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Divertículo , Masculino , Humanos , Pessoa de Meia-Idade , Fibrilação Atrial/cirurgia , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/cirurgia , Ablação por Cateter/métodos , Divertículo/complicações , Divertículo/diagnóstico por imagem , Divertículo/cirurgia , Recidiva , Diamante , Resultado do Tratamento
6.
Environ Pollut ; 346: 123688, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38431247

RESUMO

One challenge of the citrus industry is the treatment and disposal of its effluents due to their high toxicity, substantial organic load, and consequent resistance to conventional biotechnological processes. This study introduces a novel approach, using electrochemical oxidation with a boron-doped diamond anode to efficiently remove organic compounds from biodegraded pulp wash (treated using the fungus Pleurotus sajor-caju.) The findings reveal that employing a current density of 20 mA cm-2 achieves notable results, including a 44.1% reduction in color, a 70.0% decrease in chemical oxygen demand, an 88.0% reduction in turbidity, and an impressive 99.7% removal of total organic carbon (TOC) after 6 h of electrolysis. The energy consumption was estimated at 2.93 kWh g-1 of removed TOC. This sequential biological-electrochemical procedure not only significantly reduced the mortality rate (85%) of Danio rerio embryos but also reduced the incidence of morphologically altered parameters. Regarding acute toxicity (LC50) of the residue, the process demonstrated a mortality reduction of 6.97% for D. rerio and a 40.88% lethality decrease for Lactuca sativa seeds. The substantial reduction in toxicity and organic load observed in this study highlights the potential applicability of combined biological and electrochemical treatments for real agroindustrial residues or their effluents.


Assuntos
Diamante , Poluentes Químicos da Água , Diamante/química , Poluentes Químicos da Água/análise , Eletrólise/métodos , Compostos Orgânicos , Eletrodos , Oxirredução
7.
Environ Pollut ; 347: 123705, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38442825

RESUMO

The ongoing challenge of water pollution by contaminants of emerging concern calls for more effective wastewater treatment to prevent harmful side effects to the environment and human health. To this end, this study explored for the first time the implementation of single-crystal boron-doped diamond (BDD) anodes in electrochemical wastewater treatment, which stand out from the conventional polycrystalline BDD morphologies widely reported in the literature. The single-crystal BDD presented a pure diamond (sp3) content, whereas the three other investigated polycrystalline BDD electrodes displayed various properties in terms of boron doping, sp3/sp2 content, microstructure, and roughness. The effects of other process conditions, such as applied current density and anolyte concentration, were simultaneously investigated using carbamazepine (CBZ) as a representative target pollutant. The Taguchi method was applied to elucidate the optimal operating conditions that maximised either (i) the CBZ degradation rate constant (enhanced through hydroxyl radicals (•OH)) or (ii) the proportion of sulfate radicals (SO4•-) with respect to •OH. The results showed that the single-crystal BDD significantly promoted •OH formation but also that the interactions between boron doping, current density and anolyte concentration determined the underlying degradation mechanisms. Therefore, this study demonstrated that characterising the BDD material and understanding its interactions with other process operating conditions prior to degradation experiments is a crucial step to attain the optimisation of any wastewater treatment application.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Humanos , Boro/química , Oxirredução , Diamante/química , Poluentes Químicos da Água/química , Eletrodos , Purificação da Água/métodos
8.
PLoS One ; 19(3): e0298783, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38536786

RESUMO

BACKGROUND: People with mild to moderate dementia and their loved ones may experience strong existential and spiritual challenges due to the disease. People with dementia could therefore benefit greatly from ongoing conversational support. Within the literature and in supportive practice, there are very few tools that help professionals provide this type of support. Professionals may therefore be unaware of, or uncertain of, how support can be given. OBJECTIVE: To develop and test support approaches that may enable professionals to better conduct conversations with attention for existential and spiritual issues. METHODS: Participatory action research was conducted with dementia care professionals who spoke to 62 clients and 36 loved ones. Research consisted of two cycles of analyzing support, formulating strategies to try, testing and reflecting on the success of these actions and formulating new ones. The Diamond model for existential and spiritual issues regarding mild to moderate dementia, developed in previous research, was used as a framework. RESULTS: Five types of approaches, corresponding to the five fundamental polarities within the basic framework, were found to be helpful in alleviating tensions and bolstering strengths. For issues of self-confidence and -worth, an approach of exploring the felt self was developed; for issues of capacity and adaptability, an exploring daily routines approach; for issues of security and loss, an exploring a trinity of needs approach; for issues of burden and enrichment, an exploring memory approach; and for issues of faith and meaning, an exploring ones' predicament approach. When exploring these approaches, participants found sets and sequencing of questions and prompts to be helpful and transformative. CONCLUSION: Professionals can use the Diamond framework to provide conversational support to alleviate tension, enhance meaning and bolster strength for clients and loved ones.


Assuntos
Demência , Espiritualidade , Humanos , Projetos Piloto , Cuidados Paliativos , Demência/terapia , Diamante
9.
Sci Total Environ ; 923: 171454, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38438038

RESUMO

Appraising the activity of soil microbial community in relation to soil acidity and heavy metal (HM) content can help evaluate it's quality and health. Coal mining has been reported to mobilize locked HM in soil and induce acid mine drainage. In this study, agricultural soils around coal mining areas were studied and compared to baseline soils in order to comprehend the former's effect in downgrading soil quality. Acidity as well as HM fractions were significantly higher in the two contaminated zones as compared to baseline soils (p < 0.01). Moreover, self-organizing and geostatistical maps show a similar pattern of localization in metal availability and soil acidity thereby indicating a causal relationship. Sobol sensitivity, cluster, and principal component analyses were employed to enunciate the relationship between the various metal and acidity fractions with that of soil microbial properties. The results indicate a significant negative impact of metal bioavailability, and acidity on soil microbial activity. Lastly, Taylor diagrams were employed to predict soil microbial quality and health based on soil physicochemical inputs. The efficiency of several machine learning algorithms was tested to identify Random Forrest as the best model for prediction. Thus, the study imparts knowledge about soil pollution parameters, and acidity status thereby projecting soil quality which can be a pioneer in sustainable agricultural practices.


Assuntos
Compostos Azo , Minas de Carvão , Metais Pesados , Poluentes do Solo , Solo/química , Microbiologia do Solo , Poluentes do Solo/análise , Metais Pesados/análise , Diamante/análise , China , Monitoramento Ambiental
10.
J Dent ; 143: 104917, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38431188

RESUMO

OBJECTIVES: To assess the effects of aging and bleaching procedures on the color stability and surface roughness of a new single-shade composite versus multi-shade composite resins. METHODS: A single-shade composite resin (Charisma Diamond One, CDO) and 3 multi-shade composite resins (Tetric NCeram, Filtek Z350 XT, Clearfil Majesty Posterior) were tested. Thirty specimens of each material were subjected to one of the aging procedures respectively: immersion in distilled water (12 days/37 °C), immersion in coffee (12 days/37 °C), or water thermocycling (10,000 cycles/5-55 °C). All specimens underwent in-office bleaching after aging. Kruskal-Wallis tests and analysis of variance were used for statistical analysis (α=0.05). RESULTS: All materials exhibited a change of color (ΔE00), translucency (RTP), whiteness (WID) and surface roughness parameters (Sa,Sv) after aging and bleaching procedures. CDO showed the highest ΔE00 among all resins with the highest RTP value, regardless of the aging procedures. Immersion in coffee led to the significantly highest ∆E00 values and lowest RTP values for nearly all resins. Positive ΔWID1 (WID(bleaching)-WID(baseline)) values were found in distilled water immersion and thermocycling groups, while negative ΔWID1 values were found in the coffee immersion group for all materials. Besides, positive ΔWID2 (WID(bleaching)-WID(aging)) values were found in all aging groups for nearly all materials. All materials showed an increasing trend in Sa and Sv after bleaching. CONCLUSIONS: CDO showed more pronounced discoloration than multi-shade composite resins. Although the whiteness of all resins increased after bleaching, none was completely restored in the coffee immersion group. Bleaching significantly increased the surface roughness of all materials. CLINICAL SIGNIFICANCE: Charisma Diamond One is more susceptible to discoloration, which may affect its long-term success rate. Bleaching could partially reduce the color change of the composite resins but did not return them completely to their original state. The roughness of the resins increased after bleaching, prompting dentists to repolish them after bleaching.


Assuntos
Café , Resinas Compostas , Água , Diamante , Teste de Materiais , Cor , Propriedades de Superfície
11.
Oper Dent ; 49(2): 189-199, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38349843

RESUMO

The study aimed to evaluate the effect of thickness on the translucency parameter (TP) and whiteness index for dentistry (WID) of single-shade resin composites compared with a multi-shade resin composite after thermocycling. A total of 100 resin composite samples of five brands (Filtek Z250, Omnichroma, Vittra APS Unique, Zenchroma, and Charisma Diamond One) with thicknesses of 2 mm and 4 mm were prepared (n=10). CIE L*a*b* coordinates were obtained using a spectrophotometer. The resin composite samples were subjected to 10,000 thermocycles. Before and after thermocycling, TP values were calculated with the CIEDE2000 formula, and whiteness values were calculated using the WID. The influence of thickness, resin composite, and aging on these variables was analyzed using the generalized linear model (p<0.05). Omnichroma and Filtek Z250 exhibited, respectively, the highest and the lowest TP00 values compared with the other resin materials (p<0.001). The TP00 values of Zenchroma and Diamond One were similar (p>0.05). Vittra APS Unique had a lower TP than Zenchroma and Diamond One (p<0.001). Before thermocycling, the highest WID showed the combination of Vittra APS Unique with thicknesses of 2 mm (48.33±1.18). After thermocycling, the highest WID was shown in the combination of Vittra APS Unique with thicknesses of 2 mm (45.33±0.55) and 4 mm (46.23±0.94) (p<0.001). After thermocycling, the lowest WID was for the combination of Filtek Z250 with thicknesses 2 mm (21.16±0.93) and 4 mm (20.70±0.91) (p<0.001). The TP and WID values of the resin composites varied across different composites and thicknesses. Single-shade resin composites of different thicknesses demonstrated higher translucency and whiteness values than multi-shade resin composite, both before and after thermocycling.


Assuntos
Resinas Compostas , Diamante , Cor , Teste de Materiais , Espectrofotometria
12.
Urol Pract ; 11(2): 303-311, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38305182

RESUMO

INTRODUCTION: Benign prostatic hyperplasia (BPH) is a common urologic pathology for older men. The prevalence and effect on quality of life have prompted the development of new surgical procedures to manage BPH while attempting to minimize treatment side effects. The objective of this study is to utilize TriNetX, a third-party database, to investigate temporal trends in BPH procedures from 2013 to 2019 in the United States. METHODS: Male patients aged 18 to 100 who were diagnosed with BPH from 2013 to 2019 were filtered from the TriNetX Diamond Network. Yearly cohorts undergoing a BPH-related procedure were searched using Current Procedural Terminology and International Classification of Diseases 10th Revision codes. Temporal and descriptive analytics were utilized to describe trends in treatment utilization. RESULTS: There were 302,646 BPH procedures recorded on the TriNetX Diamond Network. Transurethral resection of the prostate was the most commonly performed procedure, accounting for 47.2% of procedures in 2013 and 44.9% in 2019. Photoselective vaporization of the prostate remained a popular treatment but showed the greatest decrease in utilization over time (31.8% in 2013, 21.5% in 2019). Prostatic urethral lift (UroLift) was rapidly embraced as a treatment modality, as usage increased by 18.3% over a 6-year period (0.0% in 2014, up to 18.3% in 2019). Other procedures such as Rezum (5.8%) and holmium laser enucleation of the prostate (5.1%) made up greater proportions of BPH procedures by 2019. CONCLUSIONS: Transurethral resection of the prostate was the most common procedure from 2013 to 2019. However, minimally invasive surgeries represent an increased percentage of BPH surgeries every year.


Assuntos
Hiperplasia Prostática , Ressecção Transuretral da Próstata , Humanos , Masculino , Estados Unidos/epidemiologia , Idoso , Ressecção Transuretral da Próstata/efeitos adversos , Hiperplasia Prostática/epidemiologia , Qualidade de Vida , Próstata , Diamante
13.
Protein Expr Purif ; 218: 106441, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38367654

RESUMO

Nanobodies (Nbs) represent a class of single-domain antibodies with great potential application value across diverse biotechnology fields, including therapy and diagnostics. Thymic Stromal Lymphopoietin (TSLP) is an epithelial cell-derived cytokine, playing a crucial role in the regulation of type 2 immune responses at barrier surfaces such as skin and the respiratory/gastrointestinal tract. In this study, a method for the expression and purification of anti-TSLP nanobody (Nb3341) was established at 7 L scale and subsequently scaled up to 100 L scale. Key parameters, including induction temperature, methanol feed and induction pH were identified as key factors by Plackett-Burman design (PBD) and were optimized in 7 L bioreactor, yielding optimal values of 24 °C, 8.5 mL/L/h and 6.5, respectively. Furthermore, Diamond Mix-A and Diamond MMC were demonstrated to be the optimal capture and polishing resins. The expression and purification process of Nb3341 at 100L scale resulted in 22.97 g/L titer, 98.7% SEC-HPLC purity, 95.7% AEX-HPLC purity, 4 ppm of HCP content and 1 pg/mg of HCD residue. The parameters of the scaling-up process were consistent with the results of the optimized process, further demonstrating the feasibility and stability of this method. This study provides a highly promising and competitive approach for transitioning from laboratory-scale to commercial production-scale of nanobodies.


Assuntos
Anticorpos de Domínio Único , Linfopoietina do Estroma do Timo , Anticorpos de Domínio Único/genética , Anticorpos de Domínio Único/metabolismo , Citocinas/metabolismo , Células Epiteliais , Diamante/metabolismo
14.
ACS Sens ; 9(4): 1785-1798, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38384144

RESUMO

Real-time sensing of dopamine is essential for understanding its physiological function and clarifying the pathophysiological mechanism of diseases caused by impaired dopamine systems. However, severe fouling from nonspecific protein adsorption, for a long time, limited conventional neural recording electrodes concerning recording stability. This study reported a high-antifouling nanocrystalline boron-doped diamond microsensor grown on a carbon fiber substrate. The antifouling properties of this diamond sensor were strongly related to the grain size (i.e., nanocrystalline and microcrystalline) and surface terminations (i.e., oxygen and hydrogen terminals). Experimental observations and molecular dynamics calculations demonstrated that the oxygen-terminated nanocrystalline boron-doped diamond microsensor exhibited enhanced antifouling characteristics against protein adsorption, which was attributed to the formation of a strong hydration layer as a physical and energetic barrier that prevents protein adsorption on the surface. This finally allowed for in vivo monitoring of dopamine in rat brains upon potassium chloride stimulation, thus presenting a potential solution for the design of next-generation antifouling neural recording sensors. Experimental observations and molecular dynamics calculations demonstrated that the oxygen-terminated nanocrystalline boron-doped diamond (O-NCBDD) microsensor exhibited ultrahydrophilic properties with a contact angle of 4.9°, which was prone to forming a strong hydration layer as a physical and energetic barrier to withstand the adsorption of proteins. The proposed O-NCBDD microsensor exhibited a high detection sensitivity of 5.14 µA µM-1 cm-2 and a low detection limit of 25.7 nM. This finally allowed for in vivo monitoring of dopamine with an average concentration of 1.3 µM in rat brains upon 2 µL of potassium chloride stimulation, thus presenting a potential solution for the design of next-generation antifouling neural recording sensors.


Assuntos
Diamante , Dopamina , Dopamina/análise , Dopamina/química , Animais , Diamante/química , Interações Hidrofóbicas e Hidrofílicas , Ratos , Incrustação Biológica/prevenção & controle , Boro/química , Neurotransmissores/análise , Técnicas Biossensoriais/métodos , Adsorção , Simulação de Dinâmica Molecular , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/instrumentação , Masculino , Nanopartículas/química
15.
Biosensors (Basel) ; 14(2)2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38391994

RESUMO

Amperometry is arguably the most widely used technique for studying the exocytosis of biological amines. However, the scarcity of human tissues, particularly in the context of neurological diseases, poses a challenge for exocytosis research. Human platelets, which accumulate 90% of blood serotonin, release it through exocytosis. Nevertheless, single-cell amperometry with encapsulated carbon fibers is impractical due to the small size of platelets and the limited number of secretory granules on each platelet. The recent technological improvements in amperometric multi-electrode array (MEA) devices allow simultaneous recordings from several high-performance electrodes. In this paper, we present a comparison of three MEA boron-doped diamond (BDD) devices for studying serotonin exocytosis in human platelets: (i) the BDD-on-glass MEA, (ii) the BDD-on-silicon MEA, and (iii) the BDD on amorphous quartz MEA (BDD-on-quartz MEA). Transparent electrodes offer several advantages for observing living cells, and in the case of platelets, they control activation/aggregation. BDD-on-quartz offers the advantage over previous materials of combining excellent electrochemical properties with transparency for microscopic observation. These devices are opening exciting perspectives for clinical applications.


Assuntos
Serotonina , Humanos , Boro/química , Diamante/química , Eletrodos , Exocitose , Quartzo
16.
BMC Oral Health ; 24(1): 197, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326838

RESUMO

BACKGROUND: Recently, universal single-shade resin composites have become increasingly available in the dental market. The modification of their composition can have an inadvertent effect on their physical and surface properties, and subsequently determinantal effect on their clinical function and longevity. Therefore, this study aimed to evaluate the effect of different finishing and polishing (F/P) systems on surface roughness (Ra), surface gloss (GU), and Vickers microhardness (VMH) of universal single-shade RBCs. MATERIALS AND METHODS: Four commercial RBCs were used; the universal single-shade RBCs were Omnichroma, Charisma® Diamond ONE, and Vittra APS Unique, and a conventional nanocomposite Filtek™ Z250 XT was used as a control. The 3 F/P systems were Sof-Lex™ XT, Enhance®/PoGo®, and Diacomp® Plus Twist. A total of 160 discs were used for the 3 F/P system groups for all RBCs (n = 10). After F/P, the Ra, GU, and VMH were assessed. The data were analyzed using 2-way ANOVA at p-value < 0.05. RESULTS: Significant differences were found among the four RBCs and the 3 F/P systems (p < .000). Omnichroma showed the lowest Ra and acceptable GU, but the lowest VMH. Charisma showed the highest Ra, acceptable GU, and VMH. Vittra showed acceptable Ra, GU, and VMH and Filtek showed the highest GU, VMH, and acceptable Ra. CONCLUSION: Although conventional nanohybrid RBC (Filtek Z250 XT) showed better GU and VMH values, the universal single-shade RBCs demonstrated comparable surface properties. The highest GU & VMH and lowest Ra were achieved by Diacomp followed by Enhance and Soflex.


Assuntos
Resinas Compostas , Polimento Dentário , Humanos , Teste de Materiais , Materiais Dentários , Diamante , Propriedades de Superfície
17.
BMC Oral Health ; 24(1): 164, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38302932

RESUMO

AIM: This research aimed to use an extra-oral 3D scanner for conducting volumetric analysis after caries excavation using caries-detecting dyes and chemomechanical caries removal agents in individuals with occlusal and proximal carious lesions. METHODS: Patients with occlusal (A1, A2, A3) and proximal carious lesions (B1, B2, B3) were treated with the conventional rotary technique, caries detecting dyes (CDD) and chemomechanical caries removal (CMCR) method on 90 teeth (n = 45 for each). Group A1, B1: Excavation was performed using diamond points. Group A2, B2: CDD (Sable Seek™ caries indicator, Ultradent) was applied and left for 10 s, and then the cavity was rinsed and dried. For caries removal, diamond points or excavators were used. Group A3 and B3: BRIX3000 papain gel was applied with a micro-brush for 20 s and was activated for 2 min, and then the carious tissue was removed with a sharp spoon excavator. Post-excavation cavity volume analysis was performed using a 3D scanner. The time required and the verbal pain score (VPS) for pain were scored during excavation. Post-restoration evaluation was performed at 1, 3, and 6 months FDI (Federation Dentaire Internationale) criteria. RESULTS: Comparison of age, time and volume with study groups were made using Independent Sample' t' test and one-way analysis of variance (ANOVA) for two and more than two groups, respectively. Using Cohen's Kappa Statistics, evaluators 1 and 2 agreed on caries removal status aesthetic, functional and biological properties at different follow-ups. The chi-square test revealed that the rotary groups [A1(2.5 ± 0.4 min) B1(4.0 ± 0.4 min)] had significantly less (p = 0.000) mean procedural time than CDD [A2(4.5 ± 0.4 min) B2(5.7 ± 0.4 min)] and CMCR [A3(5.4 ± 0.7 min) B3(6.2 ± 0.6 min)] groups. The CMCR group showed better patient acceptance and less pain during caries excavation than the rotary and CDD groups. CMCR group showed significantly less mean caries excavated volume(p = 0.000). Evaluation of restoration after 1-, 3-, and 6-month intervals was acceptable for all the groups. CONCLUSION: Brix3000 helps effectively remove denatured teeth with less pain or sensitivity. The time required for caries removal was lowest in the rotary method and highest in the brix3000 group, while the volume of caries removed was the lowest for brix3000 and highest for the rotary group.


Assuntos
Corantes , Cárie Dentária , Humanos , Suscetibilidade à Cárie Dentária , Dentina , Preparo da Cavidade Dentária/métodos , Cárie Dentária/diagnóstico por imagem , Cárie Dentária/terapia , Cárie Dentária/patologia , Diamante , Dor
18.
Proc Jpn Acad Ser B Phys Biol Sci ; 100(3): 149-164, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38311394

RESUMO

Since the large-volume press with a double-stage multianvil system was created by the late Professor Naoto Kawai, this apparatus (Kawai-type multianvil apparatus or KMA) has been developed for higher-pressure generation, in situ X-ray and neutron observations, deformation experiments, measurements of physical properties, synthesis of high-pressure phases, etc., utilizing its large sample volume and capacity in stable and homogeneous high temperature generation compared to those of competitive diamond anvil cells. These advancements in KMA technology have been made primarily by Japanese scientists and engineers, which yielded a wealth of new experimental data on phase transitions, melting relations, and physical characteristics of minerals and rocks, leading to significant constraints on the structures, chemical compositions, and dynamics of the deep Earth. KMA technology has also been used for synthesis of novel functional materials such as nano-polycrystalline diamond and transparent nano-ceramics, opening a new research field of ultrahigh-pressure materials science.


Assuntos
Diamante , Tecnologia , Diamante/química , Fenômenos Físicos
19.
Sci Adv ; 10(4): eadi5300, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38266085

RESUMO

The constant interplay and information exchange between cells and the microenvironment are essential to their survival and ability to execute biological functions. To date, a few leading technologies such as traction force microscopy, optical/magnetic tweezers, and molecular tension-based fluorescence microscopy are broadly used in measuring cellular forces. However, the considerable limitations, regarding the sensitivity and ambiguities in data interpretation, are hindering our thorough understanding of mechanobiology. Here, we propose an innovative approach, namely, quantum-enhanced diamond molecular tension microscopy (QDMTM), to precisely quantify the integrin-based cell adhesive forces. Specifically, we construct a force-sensing platform by conjugating the magnetic nanotags labeled, force-responsive polymer to the surface of a diamond membrane containing nitrogen-vacancy centers. Notably, the cellular forces will be converted into detectable magnetic variations in QDMTM. After careful validation, we achieved the quantitative cellular force mapping by correlating measurement with the established theoretical model. We anticipate our method can be routinely used in studies like cell-cell or cell-material interactions and mechanotransduction.


Assuntos
Comunicação Celular , Mecanotransdução Celular , Microscopia de Força Atômica , Microscopia de Fluorescência , Diamante
20.
ACS Appl Mater Interfaces ; 16(4): 4361-4374, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38232177

RESUMO

This study demonstrates the control of neuronal survival and development using nitrogen-doped ultrananocrystalline diamond (N-UNCD). We highlight the role of N-UNCD in regulating neuronal activity via near-infrared illumination, demonstrating the generation of stable photocurrents that enhance neuronal survival and neurite outgrowth and foster a more active, synchronized neuronal network. Whole transcriptome RNA sequencing reveals that diamond substrates improve cellular-substrate interaction by upregulating extracellular matrix and gap junction-related genes. Our findings underscore the potential of conductive diamond as a robust and biocompatible platform for noninvasive and effective neural tissue engineering.


Assuntos
Diamante , Engenharia Tecidual , Diamante/farmacologia , Diamante/química , Condutividade Elétrica , Neurônios/fisiologia , Sobrevivência Celular
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