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1.
Inorg Chem ; 63(17): 7992-8000, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38627375

RESUMEN

The electrochemical reduction of carbon dioxide (CO2) to produce fuels and chemicals has garnered significant attention. However, achieving control over the selectivity of the resulting products remains a challenging task, particularly within molecular systems. In this study, we employed a molecular silver complex immobilized on graphitized mesoporous carbon (GMC) as a catalyst for converting CO2 into CO, achieving an impressive selectivity of over 90% at -1.05 V vs RHE. Notably, the newly formed silver nanoparticles emerged as the active sites responsible for this high CO selectivity rather than the molecular system. Intriguingly, the introduction of copper ions into the restructured Ag-nanoparticle-decorated carbon altered the product selectivity. At -1.1 V vs RHE in 0.1 M KCl, we achieved a high C2 selectivity of 75%. Furthermore, not only the Ag-Cu bimetallic nanoparticle but also the small-sized Ag-Cu nanocluster decorated over GMC was proposed as active sites during catalytic reactions. Our straightforward approach offers valuable insights for fine-tuning the product selectivity of immobilized molecular systems, extending beyond C1 products.

2.
PLoS One ; 19(4): e0300784, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38568921

RESUMEN

PURPOSE: To assess the association between pattern changes in hemoglobin levels over time and the incidence of dementia using trajectories in females aged 55-79 years. MATERIALS AND METHODS: We conducted a retrospective cohort study using females of aged 55-79 years from the National Health Insurance Service National Health Screening Cohort in Korea. To identify hemoglobin trajectories over eight years (2002-2009), we performed a three-step approach comprising measures of change, factor analysis, and cluster analysis. Univariate and multivariate Cox proportional hazard models were used to assess the associations between hemoglobin trajectories and the incidence of dementia. RESULTS: We included 20,195 of 235,742 female participants. New dementia (N = 2664) was developed during follow-up period (2010-2015). Five hemoglobin trajectories were identified: high, mid, low, increasing, and decreasing. With high as a reference, the hazard ratios (HRs) for low and decreasing trajectories were significant, 1.28 (95% confidence interval [CI], 1.13-1.45) and 1.21 (95% CI, 1.10-1.34) in univariate models, respectively. However, only the HR for the decreasing trajectory was significant, 1.12 (95% CI, 1.01-1.24) after adjustment for confounders. CONCLUSION: The decreasing trajectory of hemoglobin levels within the normal range was associated with dementia. Even females aged 55-79 years without anemia might be vulnerable to dementia development risk.


Asunto(s)
Demencia , Humanos , Femenino , Demencia/epidemiología , Estudios Retrospectivos , Incidencia , Factores de Riesgo , Estudios Prospectivos , Hemoglobinas
5.
Acute Crit Care ; 39(1): 91-99, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38303581

RESUMEN

BACKGROUND: Mechanical power (MP) has been reported to be associated with clinical outcomes. Because the original MP equation is derived from paralyzed patients under volume-controlled ventilation, its application in practice could be limited in patients receiving pressure-controlled ventilation (PCV). Recently, a simplified equation for patients under PCV was developed. We investigated the association between MP and intensive care unit (ICU) mortality. METHODS: We conducted a retrospective analysis of Korean data from the Fourth International Study of Mechanical Ventilation. We extracted data of patients under PCV on day 1 and calculated MP using the following simplified equation: MPPCV = 0.098 ∙ respiratory rate ∙ tidal volume ∙ (ΔPinsp + positive end-expiratory pressure), where ΔPinsp is the change in airway pressure during inspiration. Patients were divided into survivors and non-survivors and then compared. Multivariable logistic regression was performed to determine association between MPPCV and ICU mortality. The interaction of MPPCV and use of neuromuscular blocking agent (NMBA) was also analyzed. RESULTS: A total of 125 patients was eligible for final analysis, of whom 38 died in the ICU. MPPCV was higher in non-survivors (17.6 vs. 26.3 J/min, P<0.001). In logistic regression analysis, only MPPCV was significantly associated with ICU mortality (odds ratio, 1.090; 95% confidence interval, 1.029-1.155; P=0.003). There was no significant effect of the interaction between MPPCV and use of NMBA on ICU mortality (P=0.579). CONCLUSIONS: MPPCV is associated with ICU mortality in patients mechanically ventilated with PCV mode, regardless of NMBA use.

6.
Sci Rep ; 14(1): 1477, 2024 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-38233543

RESUMEN

As the risk of gypsy moth outbreaks that have detrimental effects on forest ecosystem in the Northern Hemisphere increase due to climate change, a quantitative evaluation of the impact of gypsy moth defoliation is needed to support the adaptive forest management. To evaluate the host-specific impact of gypsy moth defoliation, radial growth and annual carbon accumulation were compared for one severely defoliated (Larix kaempferi (Lamb.) Carrière) and one moderate defoliated (Quercus acutissima Carruth.) host, in defoliated and non-defoliated site using tree-ring analysis. Finally, the resilience indices of radial growth variables were calculated to assess the ability of sampled trees to withstand defoliation. Gypsy moth defoliation mainly decreased latewood width and caused reduction in annual carbon absorption more than 40% for both tree species. However, L. kaempferi, showed the reduced growth until the year following defoliation, while Q. acutissima, showed no lagged growth depression and rapid growth recover. The findings show how each species reacts differently to gypsy moth defoliation and highlight the need of managing forests in a way that takes resilient tree species into account.


Asunto(s)
Larix , Mariposas Nocturnas , Quercus , Animales , Carbono , Ecosistema , Complejo de Polillas Esponjosas Voladoras , Mariposas Nocturnas/fisiología , Quercus/fisiología , República de Corea , Árboles
7.
Nat Commun ; 15(1): 645, 2024 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-38245505

RESUMEN

Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD) is currently the leading cause of chronic liver disease worldwide. Metabolic Dysfunction-Associated Steatohepatitis (MASH), an advanced form of MASLD, can progress to liver fibrosis, cirrhosis, and hepatocellular carcinoma. Based on recent findings by our team that liver 5HT2A knockout male mice suppressed steatosis and reduced fibrosis-related gene expression, we developed a peripheral 5HT2A antagonist, compound 11c for MASH. It shows good in vitro activity, stability, and in vivo pharmacokinetics (PK) in rats and dogs. Compound 11c also shows good in vivo efficacy in a diet-induced obesity (DIO) male mice model and in a choline-deficient, L-amino acid-defined, high-fat diet (CDAHFD) male mice model, effectively improving histologic features of MASH and fibrosis. According to the tissue distribution study using [14C]-labeled 11c, the compound was determined to be a peripheral 5HT2A antagonist. Collectively, first-in-class compound 11c shows promise as a therapeutic agent for the treatment of MASLD and MASH.


Asunto(s)
Hígado Graso , Neoplasias Hepáticas , Fenómenos Fisiológicos Musculoesqueléticos , Masculino , Ratones , Animales , Perros , Ratas , Hígado Graso/tratamiento farmacológico , Cirrosis Hepática/tratamiento farmacológico , Ratones Noqueados
8.
Chest ; 165(2): 313-322, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37806492

RESUMEN

BACKGROUND: Poor uptake to pulmonary rehabilitation (PR) is still challenging around the world. There have been few nationwide studies investigating whether PR impacts patient outcomes in COPD. We investigated the change of annual PR implementation rate, medical costs, and COPD outcomes including exacerbation rates and mortality between 2015 and 2019. RESEARCH QUESTION: Does PR implementation improve outcomes in patients with COPD in terms of direct cost, exacerbation, and mortality? STUDY DESIGN AND METHODS: Data of patients with COPD extracted from a large Korean Health Insurance Review and Assessment service database (2015-2019) were analyzed to determine the trends of annual PR implementation rate and direct medical costs of PR. Comparison of COPD exacerbation rates between pre-PR and post-PR, and the time to first exacerbation and mortality rate according to PR implementation, were also assessed. RESULTS: Among all patients with COPD in South Korea, only 1.43% received PR. However, the annual PR implementation rate gradually increased from 0.03% to 1.4% during 4 years, especially after health insurance coverage commencement. The direct medical cost was significantly higher in the PR group than the non-PR group, but the costs in these groups showed decreasing and increasing trends, respectively. Both the incidence rate and frequency of moderate-to-severe and severe exacerbations were lower during the post-PR period compared with the pre-PR period. The time to the first moderate-to-severe and severe exacerbations was longer in the PR group than the non-PR group. Finally, PR implementation was associated with a significant decrease in mortality. INTERPRETATION: We concluded that health insurance coverage increases PR implementation rates. Moreover, PR contributes toward improving outcomes including reducing exacerbation and mortality in patients with COPD. However, despite the well-established benefits of PR, its implementation rate remains suboptimal.


Asunto(s)
Enfermedad Pulmonar Obstructiva Crónica , Humanos , Seguro de Salud , República de Corea/epidemiología , Progresión de la Enfermedad
9.
Int J Biometeorol ; 68(2): 263-277, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38047942

RESUMEN

The selection of explanatory variables is important in modeling prediction of changes in species distribution in response to climate change. In this study, we evaluated the importance of variable selection in species distribution models. We compared two different types of models for predicting the distribution of ant species: temperature-only and both temperature and precipitation. Ants were collected at 343 forest sites across South Korea from 2006 through 2009. We used a generalized additive model (GAM) to predict the future distribution of 16 species that showed significant responses to changes in climatic factors (temperature and/or precipitation). Four types of GAMs were constructed: temperature, temperature with interaction of precipitation, temperature and precipitation without interaction, and temperature and precipitation with interaction. Most species displayed similar results between the temperatureonly and the temperature and precipitation models. The results for predicted changes in species richness were different from the temperature-only model. This indicates higher uncertainty in the prediction of species richness, which is obtained by combining the prediction results of distribution change for each species, than in the prediction of distribution change. The turnover rate of the ant assemblages was predicted to increase with decreases in temperature and increases in elevation, which was consistent with other studies. Finally, our results showed that the prediction of the distribution or diversity of organisms responding to climate change is uncertain because of the high variability of the model outputs induced by the variables used in the models.


Asunto(s)
Hormigas , Animales , Hormigas/fisiología , Temperatura , Bosques , Cambio Climático , República de Corea
10.
Tuberc Respir Dis (Seoul) ; 87(2): 185-193, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38111098

RESUMEN

BACKGROUND: The mechanisms leading to lung fibrosis are still under investigation. This study aimed to demonstrate whether antacids could prevent the development of interstitial lung disease (ILD). METHODS: This population-based longitudinal cohort study was conducted between January 2006 and December 2010 in South Korea. Eligible subjects were ≥40 years of age, exposed to proton pump inhibitors (PPI)±histamine-2 receptor antagonists (H-2 blockers) or H-2 blockers only, and had no history of ILD between 2004 and 2005. Exposure to antacids was defined as the administration of either PPI or H-2 receptor antagonists for >14 days, whereas underexposure was defined as antacid treatment administered for less than 14 days. Newly developed ILDs, including idiopathic pulmonary fibrosis (IPF), were counted during the 5-year observation period. The association between antacid exposure and ILD development was evaluated using adjusted Cox regression models with variables, such as age, sex, smoking history, and comorbidities. RESULTS: The incidence rates of ILD with/without antacid use were 43.2 and 33.8/100,000 person-years, respectively and those of IPF were 14.9 and 22.9/100,000 person-years, respectively. In multivariable analysis, exposure to antacid before the diagnosis of ILD was independently associated with a reduced development of ILD (hazard ratio [HR], 0.57; 95% confidence interval [CI], 0.45 to 0.71; p<0.001), while antacid exposure was not associated with development of IPF (HR, 0.88; 95% CI, 0.72 to 1.09; p=0.06). CONCLUSION: Antacid exposure may be independently associated with a decreased risk of ILD development.

12.
Antioxidants (Basel) ; 12(11)2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-38001766

RESUMEN

Retinyl palmitate (RP) is a retinol ester with strong antioxidant and anti-inflammatory properties as an antiwrinkle agent. However, it has poor aqueous solubility and easily degrades into inactive forms for topical applications. Therefore, we developed chitosan-coated nanocapsules (ChiNCs) to encapsulate RP using a simple nanoprecipitation method for protection against physiological conditions and to enable deep skin penetration. The as-prepared RP-loaded nanocapsules (RP@ChiNCs) loaded with approximately 5 wt.% RP exhibited a hydrodynamic diameter of 86 nm and surface charge of 24 mV. They had adequate stability to maintain their physicochemical properties after lyophilization in a biological buffer. Notably, ChiNCs provided RP with remarkable protection against degradation for 4 weeks at 37 °C. Thus, RP@ChiNCs exhibited good antioxidant activity in situ for sufficiently long periods without considerable changes in their efficacy. Furthermore, ChiNCs enhanced the skin penetration of lipophilic RP based on the inherent nature of chitosan. RP@ChiNCs exhibited good in vitro antioxidant and anti-inflammatory effects without causing any cytotoxicity in dermal fibroblasts. Accordingly, they promoted cell proliferation in a wound-scratch test and enhanced collagen synthesis. These results suggest that RP@ChiNCs are promising candidates for cosmetic and biomedical applications.

13.
ACS Omega ; 8(38): 35034-35043, 2023 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-37779938

RESUMEN

The electrochemical chlorine evolution reaction (CER) is one of the most important electrochemical reactions. Typically, iridium (Ir)- or ruthenium (Ru)-based mixed metal oxides have been used as electrocatalysts for the CER due to their high activities and durabilities. However, the scarcity of Ir and Ru has indicated the need to develop alternative earth-abundant transition-metal-based CER catalysts. In this study, we report a Co3O4 nanoparticle (NP) catalyst synthesized by a hydrothermal method. Furthermore, Ru was successfully incorporated into the Co3O4 NPs (RuxCo3-xO4 NPs) for further improvement of catalytic performance in chlorine generation. Electrokinetic analyses combined with in situ X-ray absorption near-edge structure (XANES) results suggested an identical CER mechanism for the Co3O4 NPs and RuxCo3-xO4 NPs. Various characterization techniques demonstrated that the homogeneous substitution of Ru4+ ions into the Co3+ octahedral sites enhanced the structural disorder and changed the electronic state of Co3O4, resulting in additional exposed active sites. Remarkably, the Ru0.09Co2.91O4 NP electrode exhibited outstanding stability for more than 150 h even at a high current density of 500 mA/cm2, which shows its commercial viability for active chlorine generation.

14.
Mater Today Bio ; 22: 100774, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37664795

RESUMEN

Ferrocene-based nanoparticles have garnered interest as reactive oxygen species (ROS)-responsive nanocarriers of anticancer drugs and imaging agents. However, their biomedical applications remain limited due to their poor physiological stability. PEGylation of nanocarriers improves their stability and biocompatibility. In this study, we aimed to develop novel PEG-ferrocene nanoparticles (PFNPs) with enhanced stability and ROS responsiveness for the delivery of paclitaxel (PTX) and imaging agents. PEGylation improved the stability of ferrocene nanoparticles, inhibiting their ROS-responsive destruction. Several PEG-ferrocene polymers containing different molar ratios of methacrylic acid and poly (ethylene glycol) methyl ether methacrylate was designed for optimization. ROS-responsive polymers with optimal monomer ratios were self-assembled into PFNPs with enhanced stability. The PFNPs distended, effectively releasing encapsulated PTX and imaging agents within 8 h in the presence of ROS. Furthermore, they remained stable, with no changes in their hydrodynamic diameters or polydispersity indexes after storage in an aqueous solution and biological buffer. The accumulation of PFNPs in a tumor model in vivo was 15-fold higher than a free dye. PTX-loaded PFNPs showed a substantial tumor-suppression effect, reducing tumor size to approximately 18% of that in the corresponding control group. These findings suggest a promising application of ROS-responsive PFNPs in tumor treatment as biocompatible nanocarriers of anticancer drugs and imaging agents.

15.
Bioorg Med Chem Lett ; 94: 129461, 2023 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-37652099

RESUMEN

Tryptophan hydroxylase 1 (TPH1) has emerged as a target for the treatment of metabolic diseases including obesity and fatty liver disease. A series of xanthine derivatives were synthesized and evaluated for their TPH1 inhibition. Among the synthesized compounds, compound 40 showed good in vitro activity and liver microsomal stability. Docking studies revealed that compound 40 showed better binding to TPH1 via key intermolecular interactions involving the xanthine scaffold, imidazo-thiazolyl ring, and hydroxyl-containing phenacyl moiety. In addition, compound 40 effectively suppressed the adipocyte differentiation of 3 T3-L1 cells.


Asunto(s)
Alcaloides , Enfermedad del Hígado Graso no Alcohólico , Humanos , Diuréticos , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Obesidad/tratamiento farmacológico , Triptófano Hidroxilasa/antagonistas & inhibidores , Xantinas/química , Xantinas/farmacología
16.
J Korean Med Sci ; 38(31): e242, 2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37550810

RESUMEN

BACKGROUND: Profibrotic properties of pleural mesothelial cells may play an important role in the fibrosis activity in idiopathic pulmonary fibrosis (IPF). The purpose of this study was to compare the expression of pleural mesothelial cell markers in IPF and cryptogenic organizing pneumonia (COP), with an assumption that increased expression implies increase in fibrosis. METHODS: Twenty IPF lung samples were stained by immunohistochemistry for the pleural mesothelial cell markers: leucine rich repeat neuronal 4 (LRRN4), uroplakin 3B, CC-chemokine ligand 18, and laminin-5. Nine COP lung samples were used as controls. A semi-quantitative analysis was performed to compare markers expression in IPF and COP. RESULTS: LRRN4 expression was found in epithelial lining cells along the honeycombing and fibroblastic foci in IPF, but not in the fibrotic interstitial lesion and airspace filling fibrous tufts in COP. We found a significant decrease in baseline forced vital capacity when LRRN4 expression was increased in honeycombing epithelial cells and fibroblastic foci. CONCLUSION: LRRN4 expression patterns in IPF are distinct from those in COP. Our findings suggest that mesothelial cell profibrotic property may be an important player in IPF pathogenesis and may be a clue in the irreversibility of fibrosis in IPF.


Asunto(s)
Neumonía en Organización Criptogénica , Fibrosis Pulmonar Idiopática , Neumonía Organizada , Humanos , Fibrosis Pulmonar Idiopática/patología , Pulmón/patología , Neumonía en Organización Criptogénica/diagnóstico , Neumonía en Organización Criptogénica/metabolismo , Neumonía en Organización Criptogénica/patología , Fibrosis
17.
Cell Commun Signal ; 21(1): 142, 2023 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-37328841

RESUMEN

BACKGROUND: LRRC6 is an assembly factor for dynein arms in the cytoplasm of motile ciliated cells, and when mutated, dynein arm components remained in the cytoplasm. Here, we demonstrate the role of LRRC6 in the active nuclear translocation of FOXJ1, a master regulator for cilia-associated gene transcription. METHODS: We generated Lrrc6 knockout (KO) mice, and we investigated the role of LRRC6 on ciliopathy development by using proteomic, transcriptomic, and immunofluorescence analysis. Experiments on mouse basal cell organoids confirmed the biological relevance of our findings. RESULTS: The absence of LRRC6 in multi-ciliated cells hinders the assembly of ODA and IDA components of cilia; in this study, we showed that the overall expression of proteins related to cilia decreased as well. Expression of cilia-related transcripts, specifically ODA and IDA components, dynein axonemal assembly factors, radial spokes, and central apparatus was lower in Lrrc6 KO mice than in wild-type mice. We demonstrated that FOXJ1 was present in the cytoplasm and translocated into the nucleus when LRRC6 was expressed and that this process was blocked by INI-43, an importin α inhibitor. CONCLUSIONS: Taken together, these results hinted at the LRRC6 transcriptional regulation of cilia-related genes via the nuclear translocation of FOXJ1. Video Abstract.


Asunto(s)
Cilios , Dineínas , Factores de Transcripción Forkhead , Animales , Ratones , Cilios/metabolismo , Dineínas/genética , Dineínas/metabolismo , Factores de Transcripción Forkhead/metabolismo , Regulación de la Expresión Génica , Ratones Noqueados , Proteínas/genética , Proteómica , Proteínas del Citoesqueleto/metabolismo
18.
Acute Crit Care ; 38(2): 160-171, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37313662

RESUMEN

BACKGROUND: Patients with coronavirus disease 2019 (COVID-19) infections often have macrovascular or microvascular thrombosis and inflammation, which are known to be associated with a poor prognosis. Heparin has been hypothesized that administration of heparin with treatment dose rather than prophylactic dose for prevention of deep vein thrombosis in COVID-19 patients. METHODS: Studies comparing therapeutic or intermediate anticoagulation with prophylactic anticoagulation in COVID-19 patients were eligible. Mortality, thromboembolic events, and bleeding were the primary outcomes. PubMed, Embase, the Cochrane Library, and KMbase were searched up to July 2021. A meta-analysis was performed using random-effect model. Subgroup analysis was conducted according to disease severity. RESULTS: Six randomized controlled trials (RCTs) with 4,678 patients and four cohort studies with 1,080 patients were included in this review. In the RCTs, the therapeutic or intermediate anticoagulation was associated with significant reductions in the occurrence of thromboembolic events (5 studies, n=4,664; relative risk [RR], 0.72; P=0.01), and a significant increase in bleeding events (5 studies, n=4,667; RR, 1.88; P=0.004). In the moderate patients, therapeutic or intermediate anticoagulation was more beneficial than prophylactic anticoagulation in terms of thromboembolic events, but showed significantly higher bleeding events. In the severe patients, the incidence of thromboembolic and bleeding events in the therapeutic or intermediate. CONCLUSIONS: The study findings suggest that prophylactic anticoagulant treatment should be used in patients with moderate and severe COVID-19 infection groups. Further studies are needed to determine more individualized anticoagulation guidance for all COVID-19 patients.

19.
Eur Respir J ; 62(1)2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37202155

RESUMEN

BACKGROUND: We aimed to study whether statin use is associated with lowering the development of interstitial lung disease (ILD) and idiopathic pulmonary fibrosis (IPF). METHODS: The study population was the Korean National Health Insurance Service-Health Screening Cohort. ILD and IPF cases were identified using diagnosis codes (J84.1 for ILD and J84.1A as a special code for IPF) based on the International Classification of Diseases, 10th Revision. The study participants were followed up from 1 January 2004 to 31 December 2015. Statin use was defined by the cumulative defined daily dose (cDDD) per 2-year interval and participants were categorised into never-users, <182.5, 182.5-365.0, 365.0-547.5 and ≥547.5 by cDDD. A Cox regression was used to fit models with time-dependent variables of statin use. RESULTS: Incidence rates for ILD with and without statin use were 20.0 and 44.8 per 100 000 person-years, respectively, and those for IPF were 15.6 and 19.3 per 100 000 person-years, respectively. The use of statins was independently associated with a lower incidence of ILD and IPF in a dose-response manner (p-values for trend <0.001). ILD showed respective adjusted hazard ratios (aHRs) of 1.02 (95% CI 0.87-1.20), 0.60 (95% CI 0.47-0.77), 0.27 (95% CI 0.16-0.45) and 0.24 (95% CI 0.13-0.42) according to the increasing category of statin use compared with never-users. IPF showed respective aHRs of 1.29 (95% CI 1.07-1.57), 0.74 (95% CI 0.57-0.96), 0.40 (95% CI 0.25-0.64) and 0.21 (95% CI 0.11-0.41). CONCLUSION: A population-based cohort analysis found that statin use is independently associated with a decreased risk of ILD and IPF in a dose-response manner.


Asunto(s)
Inhibidores de Hidroximetilglutaril-CoA Reductasas , Fibrosis Pulmonar Idiopática , Enfermedades Pulmonares Intersticiales , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Enfermedades Pulmonares Intersticiales/complicaciones , Fibrosis Pulmonar Idiopática/tratamiento farmacológico , Fibrosis Pulmonar Idiopática/epidemiología , Fibrosis Pulmonar Idiopática/complicaciones , Estudios de Cohortes , Incidencia
20.
Heliyon ; 9(4): e15314, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37095924

RESUMEN

Statement of problem: Biomaterials, including polymethyl methacrylate (PMMA) and bisacrylate, have been widely used as conventional interim materials and may exhibit cytotoxicity or systemic toxicity. Purpose: This study was designed to compare the mechanical properties of polylactic acid (PLA) as an alternative to conventional dental polymers for computer-aided design and manufacturing (CAD/CAM). Material and methods: Four groups (n = 20 per group) of CAD/CAM polymers were assessed. Specimens of PLA (PLA Mill) and PMMA (PMMA Mill) for subtractive manufacturing, PLA for fused deposition modeling (PLA FDM), and bisphenol for additive manufacturing by stereolithography (Bisphenol SLA) were fabricated into 2-mm-wide, 2-mm-thick and 25-mm-long specimens using a milling machine, an FDM printer, and an SLA printer, respectively.The flexural strength (FS) and elastic modulus (EM) were calculated. The surface roughness and Shore D hardness were analyzed with a 3D optical surface roughness analyzer and a Shore durometer, respectively. Results: PLA Mill showed the lowest FS (64.9 ± 8.28), followed by PLA FDM (104.27 ± 4.42 MPa), PMMA Mill (139.2 ± 20.95 MPa), and Bisphenol SLA (171.56 ± 15.38 MPa), with statistically significant differences. PLA FDM showed the highest EM, followed by PLA Mill, Bisphenol SLA, and PMMA Mill. Significant differences were observed not only between PMMA Mill and Bisphenol SLA but also between PLA FDM and PLA Mill. The lowest Shore D hardness was observed for PLA FDM, followed by PLA Mill, PMMA Mill, and Bisphenol SLA, which showed the highest value among the 4 groups, with significance. The highest values for the surface roughness parameters were observed for PLA Mill, and the lowest were observed for Bisphenol SLA. Conclusions: Among the tested CAD/CAM polymers, Bisphenol SLA was the most durable material, and the mechanical properties of PLA FDM were within the clinically acceptable range.

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