RESUMO
BACKGROUND: Despite its clinical benefits, patient compliance to remote monitoring (RM) of cardiac implantable electronic devices (CIEDs) varies and remains under-studied in diverse populations. OBJECTIVE: We sought to evaluate RM compliance, clinical outcomes, and identify demographic and socioeconomic factors affecting RM in a diverse urban population in New York. METHODS: This retrospective cohort study included patients enrolled in CIED RM at Montefiore Medical Center between December 2017 and May 2022. RM compliance was defined as the percentage of days compliant to RM transmission divided by the total prescribed days of RM. Patients were censored when they were lost to follow-up or at the time of death. The cohorts were categorized into low (≤30%), intermediate (31-69%), and high (≥70%) RM compliance groups. Statistical analyses were conducted accordingly. RESULTS: Among 853 patients, median RM compliance was 55%. Age inversely affected compliance (p < .001), and high compliance was associated with guideline-directed medical therapy (GDMT) usage and implantable cardioverter defibrillator (ICD)/cardiac resynchronization defibrillator (CRTD) devices. The low-compliance group had a higher mortality rate and fewer regular clinic visits (p < .001) than high-compliance group. Socioeconomic factors did not significantly impact compliance, while Asians showed higher compliance compared with Whites (OR 3.67; 95% CI 1.08-12.43; p = .04). Technical issues were the main reason for non-compliance. CONCLUSION: We observed suboptimal compliance to RM, which occurred most frequently in older patients. Clinic visit compliance, optimal medical therapy, and lower mortality were associated with higher compliance, whereas insufficient understanding of RM usage was the chief barrier to compliance.
Assuntos
Desfibriladores Implantáveis , Tecnologia de Sensoriamento Remoto , Humanos , Idoso , Estudos Retrospectivos , Dispositivos de Terapia de Ressincronização Cardíaca , DemografiaRESUMO
BACKGROUND: The age-adjusted prevalence of child and adolescent obesity has been stabilized in the Korean population, although severe obesity has increased with adverse health effects. In this study, we detailed the prevalence of and trends in overweight, obesity, and severe obesity in Korean children and adolescents by age group and sex from a nationally representative sample, using a new, 2017 age- and sex-specific reference for body mass index. METHODS: We collected Korea National Health and Nutrition Examination Survey data from the years 2007-2020. A total of 23,595 subjects (11,210 females) aged 2-18 years were included in this study. We calculated the recent prevalence of overweight and obesity, including severe obesity, by weighted data from 2019 and 2020. RESULTS: The prevalence of overweight and obesity (class II and class III obesity) was 23.5% and 14.2% (2.5% and 0.5%), respectively. Males showed a higher prevalence of overweight and obesity. Adolescents aged 13-15 years showed the highest prevalence of severe obesity. A positive linear trend was significant for overweight (p = 0.025), class I obesity (p < 0.001), and class II obesity (p = 0.002) for both sexes and all ages combined. However, the trend of obesity prevalence was different in each subgroup. Comparing pre- and post- COVID-19 pandemic, obesity prevalence seemed to increase, but not significantly. CONCLUSIONS: Despite previous reports that obesity in children and adolescents has remained stable, we found that the prevalence of overweight, obesity, and severe obesity has increased in Korean children and adolescents. The effects of COVID-19 on this trend require further evaluation.
Assuntos
COVID-19 , Obesidade Mórbida , Obesidade Infantil , Masculino , Feminino , Criança , Adolescente , Humanos , Obesidade Mórbida/epidemiologia , Sobrepeso/epidemiologia , Obesidade Infantil/epidemiologia , Inquéritos Nutricionais , Prevalência , Pandemias , COVID-19/epidemiologia , Índice de Massa Corporal , República da Coreia/epidemiologiaRESUMO
A large number of neuronal proteins must show correct spatiotemporal localization in order to carry out their critical functions. The mRNA transcript for the somatodendritic protein activity-regulated cytoskeleton-associated protein (Arc; also known as Arg3.1) contains two conserved introns in the 3' untranslated region (UTR), and was proposed to be a natural target for nonsense-mediated mRNA decay (NMD). However, a well-known NMD component Upf1 has differential roles in transcriptional and translational regulation of Arc gene expression. Specifically, Upf1 suppresses Arc transcription by enhancing destabilization of mRNAs encoding various transcription factors, including Mef2a. Upf1 also binds to the Arc 3'UTR, resulting in suppression of translation. Surprisingly, the Arc transcript escapes from Upf1-mediated NMD by binding to Ago2 (also known as miRISC), which blocks NMD and further suppresses Arc mRNA translation. Upf1 knockdown triggered sustained Arc expression, which contributes to Cofilin (also known as Cfl1) hyperphosphorylation and abnormal neuronal outgrowth and branching. Collectively, these data reveal that multiple levels of Upf1-mediated inhibition of Arc gene expression may allow neurons to more effectively respond to changes in neuronal activity.
Assuntos
Proteínas do Citoesqueleto/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neuritos/metabolismo , Degradação do RNAm Mediada por Códon sem Sentido , Transativadores/metabolismo , Transcrição Gênica , Animais , Linhagem Celular , Cofilina 1/genética , Cofilina 1/metabolismo , Proteínas do Citoesqueleto/genética , Camundongos , Proteínas do Tecido Nervoso/genética , Transativadores/genéticaRESUMO
THeterogeneous nuclear ribonucleoprotein (HNRNP) A1 is the most abundant and ubiquitously expressed member of the HNRNP protein family. In recent years, it has become more evident that HNRNP A1 contributes to the development of neurodegenerative diseases. However, little is known about the underlying role of HNRNP A1 in cancer development. Here, we report that HNRNP A1 expression is significantly increased in lung cancer tissues and is negatively correlated with the overall survival of patients with lung cancer. Additionally, HNRNP A1 positively regulates vaccinia-related kinase 1 (VRK1) translation via binding directly to the 3' untranslated region (UTR) of VRK1 mRNA, thus increasing cyclin D1 (CCND1) expression by VRK1-mediated phosphorylation of the cAMP response element-binding protein (CREB). Furthermore, HNRNP A1 binding to the cis-acting region of the 3'UTR of VRK1 mRNA contributes to increased lung cancer cell proliferation. Thus, our study unveils a novel role of HNRNP A1 in lung carcinogenesis via post-transcriptional regulation of VRK1 expression and suggests its potential as a therapeutic target for patients with lung cancer.
Assuntos
Ribonucleoproteína Nuclear Heterogênea A1/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias Pulmonares/patologia , Proteínas de Neoplasias/fisiologia , Biossíntese de Proteínas , Proteínas Serina-Treonina Quinases/genética , Regiões 3' não Traduzidas , Sequência de Bases , Sistemas CRISPR-Cas , Ciclo Celular , Linhagem Celular , Ciclina D1/biossíntese , Ciclina D1/genética , Fator de Iniciação 3 em Eucariotos/metabolismo , Regulação Neoplásica da Expressão Gênica , Genes Reporter , Ribonucleoproteína Nuclear Heterogênea A1/química , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/biossíntese , Neoplasias Pulmonares/genética , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Ligação Proteica , Domínios Proteicos , Mapeamento de Interação de Proteínas , Proteínas Serina-Treonina Quinases/biossíntese , Interferência de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes/metabolismo , Deleção de Sequência , Regulação para CimaRESUMO
Poly(methyl methacralyate) (PMMA) has long been used in dentistry as a base polymer for dentures, and it is recently being used for the 3D printing of dental materials. Despite its many advantages, its susceptibility to microbial colonization remains to be overcome. In this study, the interface between 3D-printed PMMA specimens and oral salivary biofilm was studied following the addition of zwitterionic materials, 2-methacryloyloxyethyl phosphorylcholine (MPC) or sulfobetaine methacrylate (SB). A significant reduction in bacterial and biofilm adhesions was observed following the addition of MPC or SB, owing to their protein-repellent properties, and there were no significant differences between the two test materials. Although the mechanical properties of the tested materials were degraded, the statistical value of the reduction was minimal and all the properties fulfilled the requirements set by the International Standard, ISO 20795-2. Additionally, both the test materials maintained their resistance to biofilm when subjected to hydrothermal fatigue, with no further deterioration of the mechanical properties. Thus, novel 3D-printable PMMA incorporated with MPC or SB shows durable oral salivary biofilm resistance with maintenance of the physical and mechanical properties.
Assuntos
Materiais Biocompatíveis/farmacologia , Biofilmes/efeitos dos fármacos , Resinas Compostas/química , Materiais Dentários/farmacologia , Boca/efeitos dos fármacos , Polímeros/química , Impressão Tridimensional/instrumentação , Aderência Bacteriana , Biofilmes/crescimento & desenvolvimento , Humanos , Teste de Materiais , Metacrilatos/química , Boca/microbiologia , Fosforilcolina/análogos & derivados , Fosforilcolina/química , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/metabolismoRESUMO
During postnatal neurodevelopment, excessive synapses must be eliminated by microglia to complete the establishment of neural circuits in the brain. The lack of synaptic regulation by microglia has been implicated in neurodevelopmental disorders such as autism, schizophrenia, and intellectual disability. Here we suggest that vaccinia-related kinase 2 (VRK2), which is expressed in microglia, may stimulate synaptic elimination by microglia. In VRK2-deficient mice (VRK2KO ), reduced numbers of presynaptic puncta within microglia were observed. Moreover, the numbers of presynaptic puncta and synapses were abnormally increased in VRK2KO mice by the second postnatal week. These differences did not persist into adulthood. Even though an increase in the number of synapses was normalized, adult VRK2KO mice showed behavioral defects in social behaviors, contextual fear memory, and spatial memory.
Assuntos
Encéfalo/enzimologia , Encéfalo/crescimento & desenvolvimento , Microglia/enzimologia , Proteínas Serina-Treonina Quinases/metabolismo , Sinapses/enzimologia , Animais , Encéfalo/citologia , Células Cultivadas , Potenciais Pós-Sinápticos Excitadores/fisiologia , Medo/fisiologia , Humanos , Masculino , Memória/fisiologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microglia/citologia , Potenciais Pós-Sinápticos em Miniatura/fisiologia , Proteínas Serina-Treonina Quinases/genética , Comportamento Social , Técnicas de Cultura de TecidosRESUMO
BACKGROUND: The cis-AB phenotype, although rare, is the relatively most frequent of ABO subgroups in Koreans. To prevent ABO mistyping of cis-AB samples, our hospital has applied a combination of the manual tile method with automated devices. Herein, we report cases of ABO mistyping detected by the combination testing system. METHODS: Cases that showed discrepant results by automated devices and the manual tile method were evaluated. These samples were also tested by the standard tube method. The automated devices used in this study were a QWALYS-3 and Galileo NEO. Exons 6 and 7 of the ABO gene were sequenced. RESULTS: 13 cases that had the cis-AB allele showed results suggestive of the cis-AB subgroup by manual methods, but were interpreted as AB by either automated device. This happened in 87.5% of these cases by QWALYS-3 and 70.0% by Galileo NEO. Genotyping results showed that 12 cases were ABO*cis-AB01/ABO*O01 or ABO*cis-AB01/ABO*O02, and one case was ABO*cis-AB01/ ABO*A102. CONCLUSION: Cis-AB samples were mistyped as AB by the automated microplate technique in some cases. We suggest that the manual tile method can be a simple supplemental test for the detection of the cis-AB phenotype, especially in countries with relatively high cis-AB prevalence.
RESUMO
While a portable microscopic cell counter has been evaluated to enumerate residual white blood cells (WBCs) in red blood cells and platelet concentrates at blood centers, it has not yet been assessed in a hospital blood bank. We investigated the performance of this device and evaluated its accuracy, along with its benefits in time management. Residual WBCs from each of 100 apheresis platelet specimens were measured manually using a Nageotte chamber, along with flow cytometry methods and an ADAM-rWBC automated instrument (NanoEnTek, Seoul, South Korea). The efficiency was calculated by measuring the time required for the analysis of one specimen ten times consecutively. Flow cytometry and the ADAM-rWBC were able to detect four sporadic cases that had residual WBCs exceeding 1/µL that were not detected by the manual method. Analysis time was the shortest with the ADAM-rWBC, followed by flow cytometry and the manual method. Our data suggest that hospital blood banks require quality control of residual WBCs; among the methods evaluated in this study, the portable microscopic cell counter offers the best time efficiency.
Assuntos
Plaquetas/metabolismo , Contagem de Leucócitos/instrumentação , Plaquetoferese/métodos , Bancos de Sangue , Citometria de Fluxo , Humanos , Contagem de Leucócitos/métodos , Controle de QualidadeRESUMO
The CAG repeat length of the androgen receptor (AR) gene, which exhibits an inverse relationship to AR sensitivity, might influence the development of the pubarche along with hyperandrogenemia. There are ethnic differences in the AR CAG repeat length, however, no Asian studies on premature pubarche (PP) have been reported, including Korea. Our objectives were to examine the hormone levels and AR CAG repeat length, and to assess their contributions to PP in Korean girls. Subjects with PP (n=16) and normal pubarche (NP, n=16), and normal controls (NC, n=16) were enrolled. The levels of dehydroepiandrosterone (DHEA), dehydroepiandrosterone-sulfate (DHEAS), 17-hydroxyprogesterone (17-OHP), and free testosterone (FT) were checked. The methylation-weighted (MW) average CAG repeat lengths were analyzed. The median ages at pubarche were 7.4 and 8.9 years in the PP and NP groups, respectively, and the levels of 17-OHP, DHEAS, and FT were similar in both groups. The PP group exhibited a higher DHEAS:DHEA ratio than the NP group (P=0.014). The medians of the MW average CAG repeat length of the AR gene were 22.4 for all subjects and did not differ among the PP (22.3), NP (22.4), and NC (22.2) groups. The AR CAG repeat lengths in the PP and NP groups did not correlate with DHEAS or FT levels. These results suggest that the AR CAG repeat length was not involved in the development of PP in Korean girls. However, excessive adrenal androgen levels, particularly those caused by increased sulfotransferase activity, might be important in the pathogenesis of PP.
Assuntos
Androgênios/sangue , Puberdade Precoce/sangue , Puberdade Precoce/genética , Receptores Androgênicos/genética , Repetições de Trinucleotídeos/genética , Estudos de Casos e Controles , Criança , Feminino , Humanos , Hiperandrogenismo/sangue , Hiperandrogenismo/genética , Resistência à Insulina , Polimorfismo Genético , República da CoreiaRESUMO
The enzyme ferulic acid decarboxylase (FADase) from Enterobacter sp. Px6-4 catalyzes the decarboxylation reaction of lignin monomers and phenolic compounds such as p-coumaric acid, caffeic acid, and ferulic acid into their corresponding 4-vinyl derivatives, that is, 4-vinylphenol, 4-vinylcatechol, and 4-vinylguaiacol, respectively. Among various ferulic acid decarboxylase enzymes, we chose the FADase from Enterobacter sp. Px6-4, whose crystal structure is known, and produced mutants to enhance its catalytic activity by random and site-directed mutagenesis. After three rounds of sequential mutations, FADase(F95L/D112N/V151I) showed approximately 34-fold higher catalytic activity than wild-type for the production of 4-vinylguaiacol from ferulic acid. Docking analyses suggested that the increased activity of FADase(F95L/D112N/V151I) could be due to formation of compact active site compared with that of the wild-type FADase. Considering the amount of phenolic compounds such as lignin monomers in the biomass components, successfully bioengineered FADase(F95L/D112N/V151I) from Enterobacter sp. Px6-4 could provide an ecofriendly biocatalytic tool for producing diverse styrene derivatives from biomass.
Assuntos
Carboxiliases/genética , Carboxiliases/metabolismo , Enterobacter/enzimologia , Enterobacter/genética , Biocatálise , Biotransformação , Domínio Catalítico , Ácidos Cumáricos/metabolismo , Descarboxilação , Guaiacol/análogos & derivados , Guaiacol/metabolismo , Simulação de Acoplamento Molecular , Mutagênese Sítio-Dirigida , Mutação , Fenóis/metabolismo , PropionatosRESUMO
To provide high-quality nursing care, nursing education requires the basic quality of self-leadership from professional nurses so that they can make self-directed and responsible judgments and decisions. Therefore, this study aimed to investigate relationships among self-leadership, positive psychological capital, consciousness of calling, and nursing professionalism in nursing students. A cross-sectional online survey of 202 students from two universities in South Korea was conducted between August and September 2022, using a convenience sampling method. A structured questionnaire was used to collect data. Data were analyzed using descriptive statistics, Pearson's correlation coefficient analysis, and bootstrapping using Hayes' PROCESS macro for mediation. A significant positive correlation was found between self-leadership, positive psychological capital, consciousness of calling, and nursing professionalism. Positive psychological capital and consciousness of calling showed an indirect mediating effect on the relationship between self-leadership and nursing professionalism. To improve nursing professionalism, programs should be developed to educate nursing students, strengthen their self-leadership skills, and increase the influence of positive psychological capital and consciousness of calling for nursing. This will ultimately contribute to improving the quality of patient care by fostering competent nursing experts.
RESUMO
Globally, there remains an unwavering increase in the incidence of cvd - from 271 million in 1990 to 523 million in 2019. Among the several modifiable and non-modifiable risk factors of heart disease, dyslipidemia is an important and prevalent risk factor mediated by both genetics and lifestyle factors. Hence, lowering lipid levels, specifically, ldl-c levels (low-density lipoprotein cholesterol), is a key strategy in decreasing the risk of cardiovascular disease. A reduction of 20 mg/dl in ldl-c levels has been found to prevent 2-3 cases of coronary artery disease (cad) for every 1000 individuals. Studies have also found reductions in ldl-c levels to be associated with a mortality benefit. However, ldl-c levels reduction may not eliminate the risk of significant cardiovascular events.
RESUMO
Amidst an aging population and escalating obesity prevalence, elucidating the impact of obesity on transcatheter aortic valve replacement (TAVR) outcomes becomes paramount. The so-called "obesity paradox"-a term denoting the counterintuitive association of obesity, typically a risk factor for cardiovascular diseases, with improved survival outcomes in TAVR patients relative to their leaner or normal-weight counterparts-merits rigorous examination. This review comprehensively investigates the complex relationship between obesity and the clinical outcomes associated with TAVR, with a specific focus on mortality and periprocedural complications. This study aims to deepen our understanding of obesity's role in TAVR and the underlying mechanisms of the obesity paradox, thereby optimizing management strategies for this patient demographic, tailored to their unique physiological and metabolic profiles.
RESUMO
Orthotopic heart transplant is the gold standard therapeutic intervention for patients with end-stage heart failure. Conventionally, heart transplant has relied on donation after brain death for organ recovery. Donation after circulatory death (DCD) is the donation of the heart after confirming that circulatory function has irreversibly ceased. DCD-orthotopic heart transplant differs from donation after brain death-orthotopic heart transplant in ways that carry implications for widespread adoption, including differences in organ recovery, storage and ethical considerations surrounding normothermic regional perfusion with DCD. Despite these differences, DCD has shown promising early outcomes, augmenting the donor pool and allowing more individuals to benefit from orthotopic heart transplant. This review aims to present the current state and future trajectory of DCD-heart transplant, examine key differences between DCD and donation after brain death, including clinical experiences and innovations in methodologies, and address the ongoing ethical challenges surrounding the new frontier in heart transplant with DCD donors.
Assuntos
Insuficiência Cardíaca , Transplante de Coração , Doadores de Tecidos , Obtenção de Tecidos e Órgãos , Humanos , Insuficiência Cardíaca/cirurgia , Insuficiência Cardíaca/fisiopatologia , Obtenção de Tecidos e Órgãos/ética , Morte Encefálica , Preservação de Órgãos/métodosRESUMO
OBJECTIVES: This study aimed to use a carboxybetaine methacrylate (CBMA) copolymer solution to surface treat 3D printed clear aligners at different fabrication stages, to impart antifouling properties, and assess the surface treatment at various fabrication stages' impact on physico-mechanical characteristics. METHODS: Surface treatments using a blend of 2-hydroxyethyl methacrylate (HEMA) and CBMA, termed CCS, were performed at various stages of 3D printed clear aligner fabrication. Experimental groups, CB1, CB2, and CB3, were determined by the stage of surface treatment during post-processing. CB1, CB2, and CB3 received treatment before post-curing, after post-curing, and after post-processing, respectively. Untreated samples served as controls. Physical and mechanical properties were assessed through tensile testing, Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and UV-Vis spectroscopy. The surface was further characterized through scanning electron microscopy and contact angle measurements. The cytotoxicity was assessed with 7-day elution and agar diffusion assays. Lastly, bacterial biofilm resistance was evaluated using confocal laser scanning microscopy. Crystal violet assay was performed using Streptococcus mutans. RESULTS: Surface treatment during CB1 stage exerted the most significantly unfavorable influence on properties of the 3D printed aligner resin. CB2 samples showed the maximum preservation of translucency even after 7-day aging. CB2 and CB3 phases showed enhanced hydrophilicity of sample surfaces with reduced adhesion of multispecies biofilm and S. mutans. SIGNIFICANCE: Application of CCS surface treatment immediately after post-curing (CB2) can enhance the biofilm resistance of 3D printed clear aligners while maintaining high fidelity to optical translucency and constituent mechanical properties.
RESUMO
Calcium silicate-based cement (CSC) is a commonly used material in endodontic treatment. However, it has limited antibacterial activity, especially for cases involving primary infections. Zinc oxide nanoparticles (ZnO-NPs) are recognized for their potential in biomedical applications due to their antibacterial properties and ability to reduce inflammation. This study aims to optimize CSC by incorporating ZnO-NPs to maintain its physical properties, enhance its antibacterial activity, and reduce the production of pro-inflammatory cytokines. ZnO-NPs were integrated into a commercial CSC (Endocem MTA) at 1 wt% (CSZ1) or 3 wt% (CSZ3). Setting time, compressive strength, and X-ray diffraction were then measured. In addition, pH, calcium ion release, and zinc ion release were measured for 7 days. Antibacterial activity against Enterococcus faecalis and viability of murine macrophages (RAW264.7) were determined using colorimetric assays. Gene expression levels of pro-inflammatory cytokines in lipopolysaccharide induced RAW264.7 were evaluated using quantitative polymerase chain reaction. Results were compared to an unmodified CSC group. In the CSZ3 group, there was a significant increase of approximately 12% in setting time and a reduction of about 36.4% in compressive strength compared to the control and CSZ1 groups. The presence of ZnO-NPs was detected in both CSZ1 and CSZ3. Both CSC and CSZ1 groups maintained an alkaline pH and released calcium ions, while zinc ions were significantly released in the CSZ1 group. Additionally, CSZ1 showed a 1.8-fold reduction of bacterial activity and exhibited around 85% reduction in colony-forming units compared to the CSC group. Furthermore, the CSZ1 group showed a more than 39% reduction in pro-inflammatory cytokine levels compared to the CSC group. Thus, enriching CSC with 1 wt% ZnO-NPs can enhance its antibacterial activity and reduce pro-inflammatory cytokines without showing any tangible adverse effects on its physical properties.
Assuntos
Compostos de Cálcio , Nanopartículas , Silicatos , Óxido de Zinco , Animais , Camundongos , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Óxidos/química , Cálcio , Nanopartículas/química , Antibacterianos/farmacologia , Zinco , CitocinasRESUMO
The study investigated the effects of temperature and centrifugation time on the efficacy of removing uncured resin from 3D-printed clear aligners. Using a photo-polymerizable polyurethane resin (Tera Harz TC-85, Graphy Inc., Seoul, Korea), aligners were printed and subjected to cleaning processes using isopropyl alcohol (IPA) or centrifugation (g-force 27.95g) at room temperature (RT, 23 °C) and high temperature (HT, 55 °C) for 2, 4, and 6 min. The control group received no treatment (NT). Cleaning efficiency was assessed through rheological analysis, weight measurement, transparency evaluation, SEM imaging, 3D geometry evaluation, stress relaxation, and cell viability tests. Results showed increased temperature and longer centrifugation times significantly reduced aligner viscosity, weight (P < 0.05), and transmittance. IPA-cleaned aligners exhibited significantly lower transparency and rougher surfaces in SEM images. All groups met ISO biocompatibility standards in cytotoxicity tests. The NT group had higher root mean square (RMS) values, indicating greater deviation from the original design. Stress relaxation tests revealed over 95% recovery in all groups after 60 min. The findings suggest that a 2-min HT centrifugation process effectively removes uncured resin without significantly impacting the aligners' physical and optical properties, making it a clinically viable option.
Assuntos
Centrifugação , Impressão Tridimensional , Temperatura , Resinas Sintéticas/química , Poliuretanos/química , Sobrevivência Celular/efeitos dos fármacos , Teste de Materiais , Humanos , AnimaisRESUMO
OBJECTIVES: To create bacteria-resistant dental CAD-CAM blocks with a biofilm-resistant effect by incorporating Nano-crystalline ceramic and polymer (NCP) with 2-methacryloyloxyethyl phosphorylcholine (MPC) and sulfobetaine methacrylate (SBMA) and at an equimolar ratio, referred to as MS. METHODS: Experimental groups comprised NCP blocks containing zwitterions at 0.15wt% (MS015) and 0.45wt% (MS045). NCP blocks without MS served as control (CTRL). Flexural strength, surface hardness, water sorption and solubility, photometric properties, and cytotoxicity were assessed for all samples. Additionally, the resistance to single and multi-species bacterial adhesion was investigated. RESULTS: MS045 showed significant reduction in flexural strength (P < 0.01) compared to both CTRL and MS015. Both MS015 and MS045 showed significantly increased water sorption and significant reduction in water solubility compared to CTRL. Light transmission remained consistent across all MS content levels, but the irradiance value decreased by 12 % in the MS045 group compared to the MS015 group. Notably, compared to the CTRL group, the MS015 group exhibited enhanced resistance to adhesion by Porphyromonas gingivalis and a multi-species salivary biofilm, with biofilm thickness and biomass reduced by 45 % and 56 %, respectively. CONCLUSIONS: NCP containing 0.15 % MS can effectively reduce adhesion of multiple species of bacteria while maintaining physical and mechanical properties. CLINICAL SIGNIFICANCE: NCP integrating zwitterions is clinically advantageous in resisting bacterial adhesion at internal and external margins of milled indirect restoration.
Assuntos
Aderência Bacteriana , Biofilmes , Cerâmica , Desenho Assistido por Computador , Resistência à Flexão , Teste de Materiais , Metacrilatos , Fosforilcolina , Propriedades de Superfície , Cerâmica/química , Metacrilatos/química , Aderência Bacteriana/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Fosforilcolina/análogos & derivados , Fosforilcolina/química , Fosforilcolina/farmacologia , Materiais Dentários/química , Polímeros/química , Humanos , Dureza , Solubilidade , Porphyromonas gingivalis/efeitos dos fármacosRESUMO
Wild-type naphthalene dioxygenase (NDO) from Pseudomonas sp. strain NCIB 9816-4 transforms relatively planar flavone and isoflavone to cis-dihydrodiols. However, this enzyme cannot catalyze the transformation of flavanone and isoflavanone in which a phenyl group bonds to the stereogenic C2 or C3 of the C-ring. Protein modeling suggested that Phe224 in the substrate binding site of NDO may play a key role in substrate specificity toward flavanone and isoflavanone. Site-directed mutants of NDO with substitution of Phe224 with Tyr biotransformed only the (S)-stereoisomers of flavanone and isoflavanone, producing an 8-OH group on the A-ring. In contrast, the Phe224Cys and Phe224Gln substitutions, which used (2S)-flavanone as a substrate, and Phe224Lys, which transformed (2S)-flavanone and (3S)-isoflavanone, each showed lower activity than the Phe224Tyr substitution. The remainder of the tested mutants had no activity with flavanone and isoflavanone. Protein docking studies of flavanone and isoflavanone to the modeled mutant enzyme structures revealed that an expanded substrate binding site, due to mutation at 224, as well as appropriate hydrophobic interaction with the residue at 224, are critical for successful binding of the substrates. Results of this study also suggested that in addition to the previously known Phe352, the Phe224 site of NDO appears to be important site for expanding the substrate range of NDO and bringing regiospecific and stereospecific hydroxylation reactions to C8 of the flavanone and isoflavanone A-rings.
Assuntos
Dioxigenases/química , Dioxigenases/metabolismo , Flavanonas/metabolismo , Isoflavonas/metabolismo , Complexos Multienzimáticos/química , Complexos Multienzimáticos/metabolismo , Pseudomonas/enzimologia , Substituição de Aminoácidos , Dioxigenases/genética , Hidroxilação , Complexos Multienzimáticos/genética , Mutagênese Sítio-DirigidaRESUMO
The isoeugenol monooxygenase (iem) gene from Pseudomonas nitroreducens Jin1, responsible for the conversion of isoeugenol to vanillin, was cloned and overexpressed in Escherichia coli. The purified Iem had a predicted molecular mass of 54 kDa. The V(max), K(M), and k(cat) values for it, using isoeugenol as substrate, were 4.2 µmol vanillin min(-1) mg(-1) of protein, 120 µM, and 3.8 s(-1), respectively. Maximum substrate turnover for Iem occurred at 30 °C and pH 9.0. An (18)Oxygen-labeling experiment revealed that oxidative cleavage of isoeugenol by Iem was catalyzed via a monooxygenation reaction, and that incorporation of the oxygen atom from O(2) into vanillin was preferable to incorporation from water. While the catalytic activity of Iem, as prepared, did not require the addition of any organic or metal cofactor, ICP-MS analysis showed 0.7 mol of iron per mol of Iem. Moreover site-directed mutagenesis of Iem of four conserved histidine residues individually, His(167), His(218), His(282), and His(471), which appear to be involved in ligand bonding with Fe(2+), resulted in a loss of activity. Enzyme activity was not appreciably influenced by preincubation of Iem with high concentrations of chelators, suggesting that iron is tightly bound. Iem has an iron-mediated mechanism that is widely spread among the three domains of life.