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1.
Nat Mater ; 23(2): 290-300, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37845321

RESUMEN

Measuring cellular and tissue mechanics inside intact living organisms is essential for interrogating the roles of force in physiological and disease processes. Current agents for studying the mechanobiology of intact, living organisms are limited by poor light penetration and material stability. Magnetomotive ultrasound is an emerging modality for real-time in vivo imaging of tissue mechanics. Nonetheless, it has poor sensitivity and spatiotemporal resolution. Here we describe magneto-gas vesicles (MGVs), protein nanostructures based on gas vesicles and magnetic nanoparticles that produce differential ultrasound signals in response to varying mechanical properties of surrounding tissues. These hybrid nanomaterials significantly improve signal strength and detection sensitivity. Furthermore, MGVs enable non-invasive, long-term and quantitative measurements of mechanical properties within three-dimensional tissues and in vivo fibrosis models. Using MGVs as novel contrast agents, we demonstrate their potential for non-invasive imaging of tissue elasticity, offering insights into mechanobiology and its application to disease diagnosis and treatment.


Asunto(s)
Nanopartículas , Nanoestructuras , Diagnóstico por Imagen/métodos , Proteínas/química , Acústica , Nanopartículas/química
2.
Nat Mater ; 23(10): 1402-1410, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39198713

RESUMEN

Novel two-dimensional semiconductor crystals can exhibit diverse physical properties beyond their inherent semiconducting attributes, making their pursuit paramount. Memristive properties, as exemplars of these attributes, are predominantly manifested in wide-bandgap materials. However, simultaneously harnessing semiconductor properties alongside memristive characteristics to produce memtransistors is challenging. Herein we prepared a class of semiconducting III-V-derived van der Waals crystals, specifically the HxA1-xBX form, exhibiting memristive characteristics. To identify candidates for the material synthesis, we conducted a systematic high-throughput screening, leading us to 44 prospective III-V candidates; of these, we successfully synthesized ten, including nitrides, phosphides, arsenides and antimonides. These materials exhibited intriguing characteristics such as electrochemical polarization and memristive phenomena while retaining their semiconductive attributes. We demonstrated the gate-tunable synaptic and logic functions within single-gate memtransistors, capitalizing on the synergistic interplay between the semiconducting and memristive properties of our two-dimensional crystals. Our approach guides the discovery of van der Waals materials with unique properties from unconventional crystal symmetries.

3.
Acc Chem Res ; 57(19): 2826-2835, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39265143

RESUMEN

ConspectusThe vertical integration of van der Waals nanomembranes (vdW NMs), composed of two-dimensional (2D) layered materials and three-dimensional (3D) freestanding films with vdW surfaces, opens new avenues for exploring novel physical phenomena and offers a promising pathway for prototyping ultrathin, superior-performance electronic and optoelectronic applications with unique functionalities. Achieving the desired functionality through vdW integration necessitates the production of high-quality individual vdW NMs, which is a fundamental prerequisite. A profound understanding of the synthetic strategies for vdW NMs, along with their fundamental working principles, is crucial in guiding the experimental design toward 3D integrated heterostructures. The foremost synthetic challenges in fabricating high-quality vdW NMs are achieving exact control over thickness and ensuring surface planarity on the atomic scale. Despite the development of numerous chemical and mechanical approaches to tackle these issues, an all-encompassing solution has yet to be realized. To address these challenges, we have developed advanced spalling techniques, specifically known as atomic spalling or 2D material-based layer transfer, which emerge as a promising technology for achieving both atomically precise thickness-engineered and atomically smooth vdW NMs. These techniques involve engineering the interfacial fracture toughness and strain energy in the vdW system, allowing for precise control over the initiation and the propagation of cracks within the vdW material based on controlled spalling theory.In this Account, we summarize our recent advancements in the atomic precision spalling technique for the preparation of vdW NMs and their applications. We begin by introducing the fundamentals of advanced spalling techniques, which are based on spalling mode fracture in bilayer systems. Following this, we succinctly describe the preparation methods for source materials for vdW NMs, with a primary focus on chemical synthesis approaches. We then delve into the working principles underlying our recent contributions to advanced spalling techniques, providing insights into how this method attains unprecedented atomic-precision control compared to other fabrication methods with a particular emphasis on tuning the interface between the stressor and the vdW system. Subsequently, we highlight cutting-edge applications based on vdW heterostructures, which combine our spalled vdW NMs. Finally, we discuss the current challenges and future directions for advanced spalling techniques, underscoring their potential to be established as a robust methodology for the preparation of high-quality vdW NMs. Our advanced spalling strategy not only ensures the reliable production of vdW NMs with exceptional control over thickness and atomic-level flatness but also provides a robust theoretical framework essential for producing high-quality vdW NMs.

4.
Nano Lett ; 2024 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-39377650

RESUMEN

Semimetal electrodes for 2D semiconductors have been extensively studied; however, research on p-type semimetals has been limited due to the scarcity of materials that satisfy both high work functions and low resistances. In response, we investigated the behavior of NiSe2 as an electrode. Utilizing a novel co-evaporation method that suppresses oxidation and contamination, we synthesized NiSe2 demonstrating a high work function of 5.53 eV, a low resistance of 5.81 × 10-5 Ω cm, and a record hole concentration exceeding 1023 cm-3. We confirmed that when WSe2 comes into contact with NiSe2, the Fermi level of WSe2 falls below the work function of NiSe2, leading to complete hole degeneration of the channel. This unusual Fermi level alignment correlates with the high hole concentration in NiSe2 and the maximum energy level of its hole pockets. Our research provides new insights into how an electrode's hole concentration affects channel behavior.

5.
Nano Lett ; 24(1): 270-278, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38157214

RESUMEN

Here, we introduce the magneto-mechanical-genetic (MMG)-driven wireless deep brain stimulation (DBS) using magnetic nanostructures for therapeutic benefits in the mouse model of Parkinson's disease (PD). Electrical DBS of the subthalamic nucleus (STN) is an effective therapy for mitigating Parkinson's motor symptoms. However, its broader application is hampered by the requirement for implanted electrodes and the lack of anatomical and cellular specificity. Using the nanoscale magnetic force actuators (m-Torquer), which deliver torque force under rotating magnetic fields to activate pre-encoded Piezo1 ion channels on target neurons, our system enables wireless and STN-specific DBS without implants, addressing key unmet challenges in the DBS field. In both late- and early-stage PD mice, MMG-DBS significantly improved locomotor activity and motor balance by 2-fold compared to untreated PD mice. Moreover, MMG-DBS enabled sustained therapeutic effects. This approach provides a non-invasive and implant-free DBS with cellular targeting capability for the effective treatment of Parkinsonian symptoms.


Asunto(s)
Estimulación Encefálica Profunda , Enfermedad de Parkinson , Trastornos Parkinsonianos , Núcleo Subtalámico , Ratones , Animales , Enfermedad de Parkinson/genética , Enfermedad de Parkinson/terapia , Trastornos Parkinsonianos/terapia , Núcleo Subtalámico/fisiología , Neuronas/fisiología , Canales Iónicos
6.
Small ; 20(25): e2307276, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38196162

RESUMEN

Graphdiyne (GDY) has garnered significant attention as a cutting-edge 2D material owing to its distinctive electronic, optoelectronic, and mechanical properties, including high mobility, direct bandgap, and remarkable flexibility. One of the key challenges hindering the implementation of this material in flexible applications is its large area and uniform synthesis. The facile growth of centimeter-scale bilayer hydrogen substituted graphdiyne (Bi-HsGDY) on germanium (Ge) substrate is achieved using a low-temperature chemical vapor deposition (CVD) method. This material's field effect transistors (FET) showcase a high carrier mobility of 52.6 cm2 V-1 s-1 and an exceptionally low contact resistance of 10 Ω µm. By transferring the as-grown Bi-HsGDY onto a flexible substrate, a long-distance piezoresistive strain sensor is demonstrated, which exhibits a remarkable gauge factor of 43.34 with a fast response time of ≈275 ms. As a proof of concept, communication by means of Morse code is implemented using a Bi-HsGDY strain sensor. It is believed that these results are anticipated to open new horizons in realizing Bi-HsGDY for innovative flexible device applications.

7.
Respir Res ; 25(1): 213, 2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38762465

RESUMEN

BACKGROUND: Obesity is associated with airway hyperresponsiveness and lung fibrosis, which may reduce the effectiveness of standard asthma treatment in individuals suffering from both conditions. Statins and proprotein convertase subtilisin/kexin-9 inhibitors not only reduce serum cholesterol, free fatty acids but also diminish renin-angiotensin system activity and exhibit anti-inflammatory effects. These mechanisms may play a role in mitigating lung pathologies associated with obesity. METHODS: Male C57BL/6 mice were induced to develop obesity through high-fat diet for 16 weeks. Conditional TGF-ß1 transgenic mice were fed a normal diet. These mice were given either atorvastatin or proprotein convertase subtilisin/kexin-9 inhibitor (alirocumab), and the impact on airway hyperresponsiveness and lung pathologies was assessed. RESULTS: High-fat diet-induced obesity enhanced airway hyperresponsiveness, lung fibrosis, macrophages in bronchoalveolar lavage fluid, and pro-inflammatory mediators in the lung. These lipid-lowering agents attenuated airway hyperresponsiveness, macrophages in BALF, lung fibrosis, serum leptin, free fatty acids, TGF-ß1, IL-1ß, IL-6, and IL-17a in the lung. Furthermore, the increased RAS, NLRP3 inflammasome, and cholecystokinin in lung tissue of obese mice were reduced with statin or alirocumab. These agents also suppressed the pro-inflammatory immune responses and lung fibrosis in TGF-ß1 over-expressed transgenic mice with normal diet. CONCLUSIONS: Lipid-lowering treatment has the potential to alleviate obesity-induced airway hyperresponsiveness and lung fibrosis by inhibiting the NLRP3 inflammasome, RAS and cholecystokinin activity.


Asunto(s)
Dieta Alta en Grasa , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Ratones Endogámicos C57BL , Ratones Transgénicos , Obesidad , Fibrosis Pulmonar , Animales , Masculino , Dieta Alta en Grasa/efectos adversos , Obesidad/tratamiento farmacológico , Obesidad/metabolismo , Ratones , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Fibrosis Pulmonar/prevención & control , Fibrosis Pulmonar/patología , Fibrosis Pulmonar/metabolismo , Fibrosis Pulmonar/tratamiento farmacológico , Inhibidores de PCSK9 , Atorvastatina/farmacología , Atorvastatina/uso terapéutico , Ratones Obesos , Proproteína Convertasa 9/metabolismo , Proproteína Convertasa 9/genética , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales/uso terapéutico , Hiperreactividad Bronquial/prevención & control , Hiperreactividad Bronquial/tratamiento farmacológico , Hiperreactividad Bronquial/metabolismo , Hiperreactividad Bronquial/fisiopatología , Anticuerpos Monoclonales Humanizados
8.
Liver Int ; 44(8): 2011-2037, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38661296

RESUMEN

BACKGROUND AND AIMS: The presence of steatosis in a donor liver and its relation to post-transplantation outcomes are not well defined. This study evaluates the effect of the presence and severity of micro- and macro-steatosis of a donor graft on post-transplantation outcomes. METHODS: The UNOS-STAR registry (2005-2019) was used to select patients who received a liver transplant graft with hepatic steatosis. The study cohort was stratified by the presence of macro- or micro-vesicular steatosis, and further stratified by histologic grade of steatosis. The primary endpoints of all-cause mortality and graft failure were compared using sequential Cox regression analysis. Analysis of specific causes of mortality was further performed. RESULTS: There were 9184 with no macro-steatosis (control), 150 with grade 3 macro-steatosis, 822 with grade 2 macro-steatosis and 12 585 with grade 1 macro-steatosis. There were 10 320 without micro-steatosis (control), 478 with grade 3 micro-steatosis, 1539 with grade 2 micro-steatosis and 10 404 with grade 1 micro-steatosis. There was no significant difference in all-cause mortality or graft failure among recipients who received a donor organ with any evidence of macro- or micro-steatosis, compared to those receiving non-steatotic grafts. There was increased mortality due to cardiac arrest among recipients of a grade 2 macro-steatosis donor organ. CONCLUSION: This study shows no significant difference in all-cause mortality or graft failure among recipients who received a donor liver with any degree of micro- or macro-steatosis. Further analysis identified increased mortality due to specific aetiologies among recipients receiving donor organs with varying grades of macro- and micro-steatosis.


Asunto(s)
Hígado Graso , Trasplante de Hígado , Sistema de Registros , Humanos , Trasplante de Hígado/efectos adversos , Trasplante de Hígado/mortalidad , Masculino , Femenino , Persona de Mediana Edad , Adulto , Hígado Graso/mortalidad , Supervivencia de Injerto , Donantes de Tejidos , Índice de Severidad de la Enfermedad , Bases de Datos Factuales , Anciano , Resultado del Tratamiento
9.
Nano Lett ; 23(11): 5227-5235, 2023 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-37192537

RESUMEN

As a new enabling nanotechnology tool for wireless, target-specific, and long-distance stimulation of mechanoreceptors in vivo, here we present a hydrogel magnetomechanical actuator (h-MMA) nanoparticle. To allow both deep-tissue penetration of input signals and efficient force generation, h-MMA integrates a two-step transduction mechanism that converts magnetic anisotropic energy to thermal energy within its magnetic core (i.e., Zn0.4Fe2.6O4 nanoparticle cluster) and then to mechanical energy to induce the surrounding polymer (i.e., pNiPMAm) shell contraction, finally delivering forces to activate targeted mechanoreceptors. We show that h-MMAs enable on-demand modulation of Notch signaling in both fluorescence reporter cell lines and a xenograft mouse model, demonstrating its utility as a powerful in vivo perturbation approach for mechanobiology interrogation in a minimally invasive and untethered manner.


Asunto(s)
Hidrogeles , Nanopartículas , Humanos , Animales , Ratones , Fenómenos Mecánicos
10.
Nano Lett ; 23(13): 6269-6275, 2023 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-37099317

RESUMEN

Tailoring the electrical properties of one-dimensional (1D) van der Waals (vdW) materials is desirable for their applications toward electronic devices by exploiting their unique characteristics. However, 1D vdW materials have not been extensively investigated for modulation of their electrical properties. Here we control doping levels and types of 1D vdW Nb2Pd3Se8 over a wide energy range by immersion in AuCl3 or ß-nicotinamide adenine dinucleotide (NADH) solutions, respectively. Through spectroscopic analyses and electrical characterizations, we confirm that the charges were effectively transferred to Nb2Pd3Se8, and the dopant concentration was adjusted to the immersion time. Furthermore, we make the axial p-n junction of 1D Nb2Pd3Se8 by a selective area p-doping using the AuCl3 solution, which exhibits rectifying behavior with an Iforward/Ireverse of 81 and an ideality factor of 1.2. Our findings could pave the way to more practical and functional electronic devices based on 1D vdW materials.

11.
J Esthet Restor Dent ; 36(2): 255-262, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37578750

RESUMEN

OBJECTIVE: Digitally-designed removable complete dentures are typically composed of a resin denture base without a metal framework. However, metal denture bases are preferable as resin bases are more susceptible to fracture. Therefore, this article introduces a unique technique that integrates computer-aided design (CAD) and conventional resin processing for the fabrication of removable complete dentures with a metal framework. CLINICAL CONSIDERATIONS: A maxillary complete denture with a metal base and a mandibular implant-retained overdenture reinforced with a metal framework were fabricated. The dentures were designed using CAD software and a tooth library. The denture bases were milled from wax disks, and artificial teeth were placed to complete the wax dentures. The metal frameworks were also designed using CAD software and produced via casting of printed resin patterns. Finally, conventional denture processing techniques were applied to obtain dentures with metal frameworks. CONCLUSIONS: A digitally designed, removable complete denture with a metal base can be successfully fabricated using the described technique, which merges digital design and conventional methods. This article demonstrates the feasibility and potential advantages of this innovative approach in denture fabrication. CLINICAL SIGNIFICANCE: The presented technique provides the following advantages: digital design features, precise space above implant overdenture attachments for a metal framework, convenience of esthetic evaluation with printed trial dentures, long-term data storage and duplication, reliable bond between the artificial teeth and denture base, and enhanced strength of the removable complete denture due to the metal reinforcement.


Asunto(s)
Diseño Asistido por Computadora , Dentadura Completa , Mandíbula , Maxilar , Humanos
12.
J Prosthet Dent ; 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38972802

RESUMEN

STATEMENT OF PROBLEM: Scan bodies play a crucial role in the accuracy of digital implant scans by serving as implant-positioning transfer devices. Previous literature has demonstrated the effects of scan body characteristics on the accuracy of digital implant scans. However, the optimal application methods of scan bodies to enhance scanning accuracy remain unclear. PURPOSE: The purpose of this systematic review was to determine the optimal application methods of scan bodies to enhance the accuracy of digital implant scans. MATERIAL AND METHODS: An electronic search was conducted by using the PubMed (MEDLINE), Web of Science, Cochrane Library, and Embase databases from November 2018 to 2023. Relevant references from the included studies were further screened manually for eligibility. Following the population, intervention, comparison, and outcome (PICO) criteria, a research question focused on identifying the optimal application method for effectively using scan bodies to enhance scanning accuracy was developed. Specific inclusion criteria involved in vitro and in vivo studies. The Checklist for Reporting In Vitro Studies (CRIS) guidelines were followed and the assessment of the risk of bias in the included studies was conducted. RESULTS: Sixteen articles that met the eligibility criteria were included in this systematic review. Two studies investigated the effect of scan body bevel orientation on the accuracy of digital implant scans, and 3 examined the impact of tightening torque on scan bodies. Among the studies focusing on completely edentulous arches, 5 recommended the use of auxiliary geometric devices on the dental arch to enhance scanning accuracy. However, 2 studies reported no improvements in accuracy after splinting scan bodies with thread. CONCLUSIONS: Different techniques for applying scan bodies, such as configuring bevel orientation, adjusting tightening torque, and attaching auxiliary geometric devices, influence the accuracy of digital implant scans. For scanning completely edentulous arches, attaching auxiliary devices to scan bodies to cover the edentulous ridge effectively enhances scanning accuracy.

13.
Respir Res ; 24(1): 85, 2023 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-36934237

RESUMEN

BACKGROUND: Particulate matter10 (PM10) can induce airway inflammation and fibrosis. Recently, chitinase-1 has been shown to play key roles in inflammation and fibrosis. We aimed to investigate the effects of chitinase-1 inhibitor in PM10-treated murine mice models. METHODS: In female BALB/c mice, PM10 was intranasally administered six times over 3 weeks, and ovalbumin (OVA) was intraperitoneally injected and then intranasally administered. Chitinase-1 inhibitor (CPX) 6 times over 3 weeks or dexamethasone 3 times in the last week were intraperitoneally administered. Two days after the last challenges, mice were euthanized. Messenger RNA sequencing using lung homogenates was conducted to evaluate signaling pathways. RESULTS: PM10 and/or OVA-induced airway inflammation and fibrosis murine models were established. CPX and dexamethasone ameliorated PM10 or PM10/OVA-induced airway hyper-responsiveness, airway inflammation, and fibrosis. CPX and dexamethasone also reduced levels of various inflammatory markers in lung homogenates. PM10 and OVA also induced changes in mRNA expression across an extreme range of genes. CPX and dexamethasone decreased levels of mRNA expression especially associated with inflammation and immune regulation. They also significantly regulated asthma and asthma-related pathways, including the JACK-STAT signaling pathway. CONCLUSIONS: Chitinase-1 suppression by CPX can regulate PM10- and OVA-induced and aggravated airway inflammation and fibrosis via an asthma-related signaling pathway.


Asunto(s)
Asma , Quitinasas , Material Particulado , Animales , Femenino , Ratones , Asma/inducido químicamente , Asma/tratamiento farmacológico , Asma/complicaciones , Líquido del Lavado Bronquioalveolar , Quitinasas/genética , Quitinasas/metabolismo , Dexametasona/farmacología , Modelos Animales de Enfermedad , Fibrosis , Inflamación/metabolismo , Pulmón/metabolismo , Ratones Endogámicos BALB C , Ovalbúmina , Material Particulado/efectos adversos , ARN Mensajero/genética
14.
Microb Ecol ; 86(2): 1050-1059, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36151339

RESUMEN

Research on niche specialization in the microbial communities of ammonia oxidizers is important for assessing the consequences of vegetation shift on nitrogen (N) cycling. In this study, soils were sampled from three tree stands (needleleaf, mixed, and evergreen broadleaf) from the Hannam experimental forest in South Korea in spring (May 2019), summer (August 2019), autumn (November 2019), and winter (January 2020). Quantitative polymerase chain reaction (qPCR) and high-throughput sequencing were used to measure the abundance and community structure of various nitrifiers: ammonia-oxidizing archaea and bacteria (AOA and AOB, respectively) as well as complete ammonia oxidizers (comammox). Nitrification rates and total ammonia oxidizer abundance were significantly higher in needleleaf forest soil than those in other forest stands, and they were lowest in evergreen broadleaf forest soil. Comammox clade B was most abundant in needleleaf and evergreen broadleaf forest soils, while AOA were significantly more abundant in mixed forest soil. The abundances of comammox clade B and AOA were negatively correlated with dissolved organic carbon. Phylogenetic analysis showed that NT-alpha and NS-gamma-2.3.2 were the most abundant AOA lineages in all the samples. The seasonal of AOA, AOB, and comammox varied with the sites, suggesting the need to examine the combinations of environmental factors when considering the effects of seasonal changes in the environment. Overall, the results suggest that potential vegetation shifts in forest ecosystems might affect nitrification activities by regulating the abundance and community structure of ammonia oxidizers.


Asunto(s)
Nitrificación , Suelo , Suelo/química , Ecosistema , Amoníaco , Filogenia , Oxidación-Reducción , Microbiología del Suelo , Archaea , Bosques
15.
Environ Sci Technol ; 57(6): 2647-2659, 2023 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-36719133

RESUMEN

CH4 emission in the Arctic has large uncertainty due to the lack of mechanistic understanding of the processes. CH4 oxidation in Arctic soil plays a critical role in the process, whereby removal of up to 90% of CH4 produced in soils by methanotrophs can occur before it reaches the atmosphere. Previous studies have reported on the importance of rising temperatures in CH4 oxidation, but because the Arctic is typically an N-limited system, fewer studies on the effects of inorganic nitrogen (N) have been reported. However, climate change and an increase of available N caused by anthropogenic activities have recently been reported, which may cause a drastic change in CH4 oxidation in Arctic soils. In this study, we demonstrate that excessive levels of available N in soil cause an increase in net CH4 emissions via the reduction of CH4 oxidation in surface soil in the Arctic tundra. In vitro experiments suggested that N in the form of NO3- is responsible for the decrease in CH4 oxidation via influencing soil bacterial and methanotrophic communities. The findings of our meta-analysis suggest that CH4 oxidation in the boreal biome is more susceptible to the addition of N than in other biomes. We provide evidence that CH4 emissions in Arctic tundra can be enhanced by an increase of available N, with profound implications for modeling CH4 dynamics in Arctic regions.


Asunto(s)
Nitrógeno , Suelo , Nitrógeno/análisis , Metano/análisis , Tundra , Ecosistema , Regiones Árticas , Microbiología del Suelo
16.
Clin Oral Implants Res ; 34(1): 33-41, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36278423

RESUMEN

OBJECTIVES: To evaluate the association between different vertical levels of the abutment margin and residual cement prevalence in cement-retained implant restorations with customized abutments. METHODS: One hundred and nine single-unit cement-retained implant restorations with a screw-access channel were included. The crowns were intraorally cemented on the abutments, and excess cement was removed. The abutment-crown complex was unscrewed, and the abutment-crown complex and peri-implant tissue were photographed. Residual cement presence was recorded by dividing the abutment-crown complex and peri-implant tissue into four quadrants: mesial, distal, buccal, and lingual. The prevalence of residual cement was compared according to the height of the custom abutment margin of the corresponding quadrant. A multilevel model was used for statistical analysis (α = .05). RESULTS: Cement remnants were discovered on 72.48% of the dental implants. When the restoration quadrants were compared, cement remnants were present on 51.38%, 39.45%, 20.18%, and 17.43% of the mesial, distal, buccal, and lingual surfaces, respectively (p < .01). Regarding the abutment margin level, cement residues were found in 60.22% and 61.4% of the 0.5 mm subgingival and ≥1 mm subgingival margin groups, respectively, which were significantly more than those in the supragingival (23.65%) and equigingival (26.59%) margin groups (p < .01). After adjustment for confounding factors, the adjusted odds ratio (with 95% confidence interval) for residual cement in the subgingival margin groups was 3.664 (1.71, 7.852) when compared to the supragingival and equigingival margin groups. CONCLUSIONS: The risk of residual cement occurrence was 3.66-fold higher with a subgingival abutment margin than with supragingival and equigingival abutment margins.


Asunto(s)
Cementación , Implantes Dentales , Pilares Dentales , Prótesis Dental de Soporte Implantado , Cementos Dentales , Cementos de Ionómero Vítreo/química , Coronas
17.
Nano Lett ; 22(18): 7415-7422, 2022 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-36069378

RESUMEN

Regulation of genetic activity in single cells and tissues is pivotal to determine key cellular functions in current biomedicine, yet the conventional biochemical activators lack spatiotemporal precision due to the diffusion-mediated slow kinetics and nonselectivity. Here, we describe a magnetogenetic method for target-specific activation of a clustered regularly interspaced short palindromic repeats (CRISPR) system for the regulation of intracellular proteins. We used magnetomechanical force generated by the magnetic nanostructure to activate pre-encoded Piezo1, the mechanosensitive ion channel, on the target cell. The activated Piezo1 further triggers the intracellular Ca2+ signaling pathway, inducing the pre-encoded genes to express genes of interest (GOIs), which is Cas9 protein for the CRISPR regulation of the target proteins. We demonstrated that this magnetogenetic CRISPR system successfully edits the target genome for both in vitro and pseudo-in vivo environments, providing a versatile magnetic platform for remote gene editing of animals with various size scales.


Asunto(s)
Proteína 9 Asociada a CRISPR , Edición Génica , Animales , Proteína 9 Asociada a CRISPR/genética , Sistemas CRISPR-Cas/genética , Edición Génica/métodos , Canales Iónicos/genética
18.
J Prosthet Dent ; 130(6): 927-934, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35850874

RESUMEN

STATEMENT OF PROBLEM: Interim restorations are often used along with mouth rinses during the healing period following surgical procedures. However, evidence regarding the color and surface properties of digitally fabricated interim restorations after oral rinsing is lacking. PURPOSE: The purpose of this in vitro study was to evaluate whether different mouth rinses could affect the color and surface roughness of milled and printed interim restorations after simulated oral rinsing. MATERIAL AND METHODS: Disk-shaped specimens (Ø15×2 mm; N=180) were fabricated by using conventional (Jet Tooth Shade), milled (Yamahachi PMMA Disk), and printed (NextDent C&B) resin materials. All resin specimens were divided into 3 different groups according to the rinsing material: distilled water, whitening mouth rinse (Listerine Healthy White), and conventional mouth rinse (Listerine Cool Mint). The specimens were further allocated into short- and long-term subgroups, and oral rinsing simulation was performed (n=10). Short-term rinsing simulated the conditions in a usual interim restoration period, and long-term rinsing was performed to evaluate the properties of the interim materials. The color differences (CIEDE2000, ΔE00) between the baseline and each time point were determined by using a spectrophotometer. The surface roughness of the tested specimens was measured by using a confocal laser scanning microscope. Kruskal-Wallis and Friedman tests with nonparametric pairwise comparisons were used to analyze the data (α=.05). RESULTS: On simulation of a 6-month use of the mouth rinse, the color change in the milled resin did not differ from that in the conventional resin (P>.334), but the printed resin showed a significantly greater color change than the other resins (P<.007). The greatest color change with the printed resin was observed when a conventional mouth rinse was used. However, all color changes were below a perceptible threshold of 1.30. When daily rinsing for 14 years was simulated, all resin groups showed a perceptible color change when conventional mouth rinse was used, and the printed resin showed the greatest median ±interquartile range ΔE00 (2.24 ±0.2). In both short- and long-term simulations, the printed resin rinsed with the conventional mouth rinse showed significantly greater roughness than that rinsed with distilled water (P<.009). CONCLUSIONS: The printed resin showed higher stainability than the conventional resin, and the color change was greatest with the conventional mouth rinse. However, in 6 months of daily mouth rinse simulation, all the tested resin materials exhibited imperceptible color change and clinically acceptable surface roughness.


Asunto(s)
Antisépticos Bucales , Diente , Materiales Dentales , Agua , Ensayo de Materiales , Propiedades de Superficie , Color
19.
Molecules ; 29(1)2023 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-38202660

RESUMEN

In this paper, we demonstrate the use of polymer dispersed liquid crystal (PDLC) imprinted with a microlens array (MLA) via solution process to improve the outcoupling efficiency of organic light emitting diodes (OLEDs). The PDLC, well known for its scattering effect, is an excellent technology for improving the outcoupling efficiency of OLEDs. Additionally, we introduce a simple spin-coating process to fabricate PDLC which is adaptable for future solution-processed OLEDs. The MLA-imprinted PDLC applied OLED shows an enhancement factor of 1.22 in outcoupling efficiency which is a 37.5% increase compared to the existing PDLC techniques without changing the electrical properties of the OLED. Through this approach, we can expect the roll-to-roll based extremely flexible OLED, and with further research on pattering PDLC by various templates, higher outcoupling efficiency is achievable through a simple UV irradiation process.

20.
Asian Pac J Allergy Immunol ; 41(3): 244-252, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33068368

RESUMEN

BACKGROUND: It is difficult to differentiate between hypereosinophilic syndrome (HES) and antineutrophil cytoplasmic antibody (ANCA)-negative eosinophilic granulomatosis with polyangiitis (EGPA). OBJECTIVE: We compared laboratory data at diagnosis between Korean patients with HES and ANCA-negative EGPA and investigated independent laboratory predictors suggesting HES. METHODS: We reviewed the medical records of 41 HES patients and 16 ANCA-negative EGPA patients. The cut-offs were extrapolated by the receiver operator characteristic (ROC) curve. The odds ratio (OR) and relative risk (RR) were assessed using the multivariable logistic regression analysis and the chi-square test, respectively. We developed a new equation by assigning a weight to each variable according to the slopes (B) and expressed a decimal as the nearest integer. RESULTS: HES patients had a higher median WBC and eosinophil counts than ANCA-negative EGPA patients. The cutoffs of WBC and eosinophil counts for HES were set at 9,900.0/mm3 and 2,400.0/mm3. In the multivariable analysis, WBC count ≥ 9,900.0/mm3 (B 1.763) and eosinophil count ≥ 2,400.0/mm3 (B 1.515) were significantly associated with HES. An equation was as follows: HES-suggesting laboratory index (HSLI) = 2 × (WBC count ≥ 9,900.0/mm3 (1 = No or 2 = Yes)) + 1.5 × (eosinophil count ≥ 2,400.0/mm3 (1 = No or 2 = Yes)). The cut-off of HSLI for HES was 4.25. Patients with HSLI ≥ 4.25 exhibited a significantly high RR (51.429) for HES, compared to those without. CONCLUSIONS: In conclusion, the cut-off of HSLI derived from WBC and eosinophil counts could be an independent predictor of HES in patients suspected of both HES and ANCA-negative EGPA.


Asunto(s)
Síndrome de Churg-Strauss , Granulomatosis con Poliangitis , Síndrome Hipereosinofílico , Humanos , Anticuerpos Anticitoplasma de Neutrófilos , Granulomatosis con Poliangitis/diagnóstico , Síndrome de Churg-Strauss/diagnóstico , Eosinófilos , Síndrome Hipereosinofílico/diagnóstico
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