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BACKGROUND: Familial chylomicronemia syndrome (FCS) is a rare monogenic form of severe hypertriglyceridemia, caused by mutations in genes involved in triglyceride metabolism. Herein, we report the case of a Korean family with familial chylomicronemia syndrome caused by compound heterozygous deletions of glycosylphosphatidylinositol-anchored high-density lipoprotein-binding protein 1 (GPIHBP1). CASE PRESENTATION: A 4-year-old boy was referred for the evaluation of severe hypertriglyceridemia (3734 mg/dL) that was incidentally detected 4 months prior. His elder brother also demonstrated an elevated triglyceride level of 2133 mg/dL at the age of 9. Lipoprotein electrophoresis revealed the presence of chylomicrons, an increase in the proportion of pre-beta lipoproteins, and low serum lipoprotein lipase levels. The patient's parents and first elder brother had stable lipid profiles. For suspected FCS, genetic testing was performed using the next-generation sequencing-based analysis of 31 lipid metabolism-associated genes, which revealed no pathogenic variants. However, copy number variant screening using sequencing depth information suggested large heterozygous deletion encompassing all the coding exons of GPIHBP1. A real-time quantitative polymerase chain reaction was performed to validate the deletion site. The results showed that the siblings had two heterozygous copy number variants consisting of the whole gene and an exon 4 deletion, each inherited from their parents. During the follow-up period of 17 months, the patient did not develop pancreatitis, following dietary intervention. CONCLUSION: These siblings' case of familial chylomicronemia syndrome caused by rare GPIHBP1 deletions highlight the implementation of copy number variants-beyond next-generation sequencing-as an important consideration in diagnosis. Accurate genetic diagnosis is necessary to establish the etiology of severe hypertriglyceridemia, which increases the risk of pancreatitis.
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Hiperlipoproteinemia Tipo I , Hipertrigliceridemia , Pancreatite , Receptores de Lipoproteínas , Pré-Escolar , Humanos , Masculino , Hiperlipoproteinemia Tipo I/diagnóstico , Hiperlipoproteinemia Tipo I/genética , Hipertrigliceridemia/etiologia , Lipase Lipoproteica/genética , Lipase Lipoproteica/metabolismo , Receptores de Lipoproteínas/genética , Receptores de Lipoproteínas/química , Receptores de Lipoproteínas/metabolismo , Irmãos , Triglicerídeos , CriançaRESUMO
Parkinson's disease (PD) is the second most common neurodegenerative disease worldwide. Given its prevalence, reliable biomarkers for early diagnosis are required. Exosomal proteins within extracellular nanovesicles are promising candidates for diagnostic, screening, prognostic, and disease monitoring purposes in neurological diseases such as PD. This review aims to evaluate the potential of extracellular vesicle proteins or miRNAs as biomarkers for PD. A comprehensive literature search until January 2024 was conducted across multiple databases, including PubMed, EMBASE, Web of Science, and Cochrane Library, to identify relevant studies reporting exosome biomarkers in blood samples from PD patients. Out of 417 articles screened, 47 studies were selected for analysis. Among exosomal protein biomarkers, α-synuclein, tau, Amyloid ß 1-42, and C-X-C motif chemokine ligand 12 (CXCL12) were identified as significant markers for PD. Concerning miRNA biomarkers, miRNA-24, miR-23b-3p, miR-195-3p, miR-29c, and mir-331-5p are promising across studies. α-synuclein exhibited increased levels in PD patients compared to control groups in twenty-one studies, while a decrease was observed in three studies. Our meta-analysis revealed a significant difference in total exosomal α-synuclein levels between PD patients and healthy controls (standardized mean difference [SMD] = 1.369, 95% confidence interval [CI] = 0.893 to 1.846, p < 0.001), although these results are limited by data availability. Furthermore, α-synuclein levels significantly differ between PD patients and healthy controls (SMD = 1.471, 95% CI = 0.941 to 2.002, p < 0.001). In conclusion, certain exosomal proteins and multiple miRNAs could serve as potential biomarkers for diagnosis, prognosis prediction, and assessment of disease progression in PD.
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Biomarcadores , Exossomos , MicroRNAs , Doença de Parkinson , Humanos , Doença de Parkinson/diagnóstico , Doença de Parkinson/sangue , Doença de Parkinson/genética , Exossomos/metabolismo , Exossomos/genética , Biomarcadores/sangue , MicroRNAs/sangue , MicroRNAs/genética , alfa-Sinucleína/sangue , Peptídeos beta-Amiloides/sangueRESUMO
BACKGROUND: This study investigated the association between handgrip strength (HGS) and physical activity (PA) at different levels in Korean adults for the purpose of providing direction for increasing HGS, which represents muscular strength, and increasing understanding of PA and HGS. METHODS: This study targeted adults aged ≥30 years from the Korean National Health and Nutrition Examination Survey (2014-2019), including 31,888 participants for analysis. HGS was defined as the maximum value of the three measurements of the dominant hand. PA was defined as an activity that causes shortness of breath or a fast heartbeat. Data were weighted according to survey district and household data; p < .05 was considered statistically significant. RESULTS: In men, HGS in those aged 30-64 years was significantly associated with high-intensity PA and in those aged ≥65 years was associated with moderate-intensity PA. In women, HGS in those aged 30-64 years was also significantly associated with high-intensity PA, and in those aged ≥65 years, it was significantly associated with both moderate- and high-intensity PA. Moreover, compared to participants who did not participate in weight training, those who participated showed higher HGS in both sexes. CONCLUSIONS: This study demonstrated age- and sex-specific characteristics of the association between HGS and PA in Koreans. The findings suggest the importance of managing health by considering differences in age- and sex-related PA. In particular, this study suggests that adequate PA is necessary despite its importance of PA for elderly individuals.
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Major depressive disorder (MDD) is a highly prevalent psychiatric condition affecting an estimated 280 million individuals globally. Despite the occurrence of suicidal behaviors across various psychiatric conditions, MDD is distinctly associated with the highest risk of suicide attempts and death within this population. In this study, we focused on MDD to identify potential inflammatory biomarkers associated with suicidal risk, given the relationship between depressive states and suicidal ideation. Articles published before June 2023 were searched in PubMed, Embase, Web of Science, and the Cochrane Library to identify all relevant studies reporting blood inflammatory biomarkers in patients with MDD with suicide-related behaviors. Of 571 articles, 24 were included in this study. Overall, 43 significant biomarkers associated with MDD and suicide-related behaviors were identified. Our study provided compelling evidence of significant alterations in peripheral inflammatory factors in MDD patients with suicide-related behaviors, demonstrating the potential roles of interleukin (IL)-1ß, IL-6, C-reactive protein, C-C motif chemokine ligand 2, and tumor necrosis factor-α as biomarkers. These findings underscore the intricate relationship between the inflammatory processes of these biomarkers and their interactions in MDD with suicidal risk.
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Since December 30, 2017, the Seoul Metropolitan Government, Republic of Korea, has been implementing emergency reduction measures (ERMs) restricting the operation of industrial sites, thermal power plants, and vehicles when air quality is expected to deteriorate. ERMs are implemented when the present observed concentration of particulate matter (PM) of aerodynamic diameter less than 2.5 µm (PM2.5) and/or the predicted values for the following day exceed a threshold value. In this study, the effectiveness of ERMs was evaluated for 33 days with and 6 days without ERM implementation but where the PM2.5 concentration exceeded the threshold value, until March 15, 2021. Of the 33 days of ERM implementation, on 7 days it was executed despite the thresholds not being met. The ERM on these days might have been properly executed because the pre-notice and implementation of ERM might have reduced the local emissions of air pollutants. Our major findings are that even on days of ERM implementation, there were marginal reductions in vehicle traffic, thermal power generation, and industrial emissions. Second, the concentrations of PM2.5 and related air pollutants in Seoul were almost unchanged for most ERM implementation episodes. Third, most of the 39 (= 33 + 6) days when the air quality worsened were caused by the transboundary transport of air pollutants from China. In conclusion, it was revealed that the currently executed ERM law is insufficient for effectively reducing PM2.5. To achieve the required reductions, it is necessary to undertake stricter policies in Seoul and its neighboring regions.
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Poluentes Atmosféricos , Material Particulado , Seul , Monitoramento Ambiental , República da CoreiaRESUMO
We report the unique synthesis of chiral supramolecular tri- and penta-BCPs with controllable chirality using kinetically adjusted seeded supramolecular copolymerization in THF and DMSO (99 : 1, v/v). Tetraphenylethylene (d- and l-TPE) derivatives bearing d- and l-alanine side chains formed thermodynamically favored chiral products via a kinetically trapped in monomeric state with a long lag phase. In contrast, achiral TPE-G containing glycine moieties did not form a supramolecular polymer owing to the energy barrier in its kinetically trapped state. We show that the copolymerization of the metastable states of TPE-G not only enables the generation of supramolecular BCPs by the seeded living growth method, but also transfers chirality at the seed ends. This research demonstrates the generation of chiral supramolecular tri- and penta-BCPs with B-A-B, A-B-A-B-A, and C-B-A-B-C block patterns accompanying chirality transfer via seeded living polymerization.
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Alanina , Tetranitrato de Pentaeritritol , Polimerização , GlicinaRESUMO
Stroke is a primary debilitating disease in adults, occurring in 15 million individuals each year and causing high mortality and disability rates. The latest estimate revealed that stroke is currently the second leading cause of death worldwide. Post-stroke cognitive impairment (PSCI), one of the major complications after stroke, is frequently underdiagnosed. However, stroke has been reported to increase the risk of cognitive impairment by at least five to eight times. In recent decades, peripheral blood molecular biomarkers for stroke have emerged as diagnostic, prognostic, and therapeutic targets. In this study, we aimed to evaluate some blood-derived proteins for stroke, especially related to brain damage and cognitive impairments, by conducting a systematic review and meta-analysis and discussing the possibility of these proteins as biomarkers for PSCI. Articles published before 26 July 2021 were searched in PubMed, Embase, the Web of Science, and the Cochrane Library to identify all relevant studies reporting blood biomarkers in patients with stroke. Among 1820 articles, 40 were finally identified for this study. We meta-analyzed eight peripheral biomarker candidates: homocysteine (Hcy), high-density lipoprotein cholesterol (HDL-C), C-reactive protein (CRP), low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), triglyceride (TG), uric acid, and glycated hemoglobin (HbA1c). The Hcy, CRP, TC, and LDL-C levels were significantly higher in patients with PSCI than in the non-PSCI group; however, the HDL-C, TG, uric acid, and HbA1c levels were not different between the two groups. Based on our findings, we suggest the Hcy, CRP, TC, and LDL-C as possible biomarkers in patients with post-stroke cognitive impairment. Thus, certain blood proteins could be suggested as effective biomarkers for PSCI.
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Biomarcadores/sangue , Disfunção Cognitiva/sangue , Disfunção Cognitiva/etiologia , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/complicações , HumanosRESUMO
Circularly polarized luminescence (CPL) with tunable chirality is currently a challenging issue in the development of supramolecular nanomaterials. We herein report the formation of helical nanoribbons which grow into helical tubes through dynamic helicity inversion. For this, chiral PtII complexes of terpyridine derivatives, namely S-trans-1 and R-trans-1, with respective S- and R-alanine subunits and incorporating trans-double bonds in the alkyl chain were prepared. In DMSO/H2 O (5 : 1 v/v), S-trans-1 initially forms a fibrous self-assembled product, which then undergoes dynamic transformation into helical tubes (left-handed or M-type) through helical ribbons (right-handed or P-type). Interestingly, both helical supramolecular architectures are capable of emitting CPL signals. The metastable helical ribbons show CPL signals (glum =±4.7×10-2 ) at 570â nm. Meanwhile, the nanotubes, which are the thermodynamic products, show intense CPL signals (glum =±5.6×10-2 ) at 610â nm accompanied by helicity inversion. This study provides an efficient way to develop highly dissymmetric CPL nanomaterials by regulating the morphology of metallosupramolecular architectures.
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We report a unique dynamic morphology transformation of a Ag+-coordinated supramolecular nanostructure accompanying the conversion of complex structures in aqueous solution. In the presence of AgNO3 (1.0 equiv), the achiral bipyridine-based ligand 1G, possessing hydrazine and glycine moieties, preferentially generated a 1D needle-like structure (nanostructure I) based on the 1GAgNO3 complex (1G:Ag+ = 1:1) as a metastable product. Nanostructure I was then transformed into nanostructure II, which was composed of the 1G3Ag2(NO3)2 complex (1G:Ag+ = 3:2) as the thermodynamically stable product. This nanostructure exhibited a 1D helical tubular structure with a uniform diameter via a 2D ribbon as an intermediator, which led to the generation of a circular dichroism (CD) signal with right-handed (P-type) helicity. The observed dynamic transformation was attributed to formation of the thermodynamically favored helical 1G3Ag2(NO3)2 complex. In addition, the helical 1G3Ag2(NO3)2 complex acted as an initiator in the transformation from the 1D needle-like structure to the 1D helical tube via a 2D ribbon. The enhanced ΔG° value of nanostructure II compared to that of nanostructure I confirmed that nanostructure II is thermodynamically stable. More importantly, the transformation of supramolecular nanostructure I to nanostructure II occurred via an "on" pathway, even though the 1GAgNO3 complex was converted to the 1G3Ag2(NO3)2 complex, which did not involve dissociation from nanostructure I into the monomeric 1GAgNO3 complex species. In the kinetic study, the NO3- anion was found to act as an accelerator for the dynamic transformation from nanostructure I to nanostructure II. This result provides the first example of a dynamic transformation of a 1D needle-like structure into a 1D tubular structure via a 2D ribbon structure, accompanied by the conversion of a complex structure and the generation of a large CD signal for the metallo-supramolecular nanostructure. This study may open up new avenues to the understanding of a dynamic morphology transformation process in biological systems.
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Parkinson's disease (PD) is a progressive neurodegenerative disease characterized by the loss of dopaminergic neurons in the substantia nigra. Several treatments for PD have focused on the management of physical symptoms using dopaminergic agents. However, these treatments induce various adverse effects, including hallucinations and cognitive impairment, owing to non-targeted brain delivery, while alleviating motor symptoms. Furthermore, these therapies are not considered ultimate cures owing to limited brain self-repair and regeneration abilities. In the present study, we aimed to investigate the therapeutic potential of human adipose-derived stem cells (hASCs) using magnetic nanoparticles in a 6-hydroxydopamine (6-OHDA)-induced PD mouse model. We used the Maestro imaging system and magnetic resonance imaging (MRI) for in vivo tracking after transplantation of magnetic nanoparticle-loaded hASCs to the PD mouse model. The Maestro imaging system revealed strong hASCs signals in the brains of PD model mice. In particular, MRI revealed hASCs distribution in the substantia nigra of hASCs-injected PD mice. Behavioral evaluations, including apomorphine-induced rotation and rotarod performance, were significantly recovered in hASCs-injected 6-OHDA induced PD mice when compared with saline-treated counterparts. Herein, we investigated whether hASCs transplantation using magnetic nanoparticles recovered motor functions through targeted brain distribution in a 6-OHDA induced PD mice. These results indicate that magnetic nanoparticle-based hASCs transplantation could be a potential therapeutic strategy in PD.
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Tecido Adiposo/citologia , Nanopartículas de Magnetita , Doença de Parkinson/terapia , Transplante de Células-Tronco , Células-Tronco/citologia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Terapia Baseada em Transplante de Células e Tecidos/efeitos adversos , Terapia Baseada em Transplante de Células e Tecidos/métodos , Modelos Animais de Doenças , Imunofluorescência/métodos , Humanos , Imuno-Histoquímica , Camundongos , Oxidopamina/efeitos adversos , Doença de Parkinson/diagnóstico , Doença de Parkinson/etiologia , Transplante de Células-Tronco/efeitos adversos , Transplante de Células-Tronco/métodos , Células-Tronco/metabolismoRESUMO
BACKGROUND: The global COVID-19 pandemic has increased cyber communication, causing nursing students' clinical practice to be held in cyberspace. Thus, it is essential to ensure that nursing students develop comprehensive cyber ethics awareness. Moreover, cyberbullying is becoming more widespread and is an increasingly relevant new concept. OBJECTIVES: This study aimed to assess the experiences of cyberbullying among nursing students during clinical practice and determine the effects of cyberbullying victimization and cyber environments on their cyber ethics awareness. RESEARCH DESIGN: Data for this descriptive cross-sectional study were collected in July 2020 using a self-reported questionnaire and analyzed using hierarchical regression. PARTICIPANTS AND RESEARCH CONTEXT: The study included data from 291 nursing students with more than 6 months of clinical experience who were enrolled in two nursing universities in two cities in South Korea. ETHICAL CONSIDERATIONS: This study was conducted after obtaining approval from the Institutional Review Board of G University. Written, informed consent was obtained from all participants. RESULTS: Cyberbullying victimization experiences during clinical practice were few. The most common cyberbullies of work- and person-related cyberbullying were nurses and classmates, respectively. DISCUSSION: Cyber ethics awareness was affected by cyber anonymity and the perceived seriousness of cyberbullying; cyberbullying related to clinical practices was a new factor that significantly affected cyber ethics awareness. CONCLUSIONS: Hospitals and nursing universities should develop a multi-dimensional, comprehensive, and effective nursing intervention education program to be integrated into the nursing curriculum to enhance cyber ethics awareness and reduce cyberbullying of nursing students.
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COVID-19 , Cyberbullying , Ética em Enfermagem , Estudantes de Enfermagem , Estudos Transversais , Humanos , Pandemias , SARS-CoV-2RESUMO
BACKGROUND: The definition of community health outreach to promote the health of vulnerable populations depends heavily on the particulars of the given health project and community. There is no consistency in the definitions attached to the concept itself. Our study aimed to clarify the general definition of community health outreach to facilitate its understanding and use. METHODS: Walker and Avant's (2010) method of concept analysis was used to understand community health outreach. A total of 45 articles were included in the analysis after having searched for text on database portals like PubMed, Scopus, CINAHL complete and EMBASE published between 2010 and 2018. RESULTS: The defining attributes of the concept of community health outreach were purposive, temporary, mobile and collaboration with community. The antecedents were population facing health risks and awareness of health risks. The consequences were increased accessibility and health promotion. CONCLUSION: This study proposed the definition of community health outreach as a temporary, mobile project that involves the collaboration of a community to undertake its purposeful health intervention of reaching a population facing health risks. This definition provides a general understanding of the outreach undertaken by health workers and enables the strong connection between health professionals and community residents.
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Relações Comunidade-Instituição , Promoção da Saúde/organização & administração , Saúde Pública , Formação de Conceito , HumanosRESUMO
Alzheimer's disease (AD), a progressive neurodegenerative disorder, is characterized clinically by cognitive decline and pathologically by the development of amyloid plaques. AD is the most common cause of dementia among older people. However, there is currently no cure for AD. In this study, we aimed to elucidate the therapeutic effects of human amniotic epithelial stem cells (hAESCs) in a transgenic mouse model of AD. Tg2576 transgenic (Tg) mice underwent behavioral tests, namely the Morris water maze and Y-maze tests, to assess their cognitive function. In the Morris water maze test, hAESC-treated Tg mice exhibited significantly shorter escape latencies than vehicle-treated Tg mice. In the Y-maze test, hAESC-treated Tg mice exhibited significantly higher rate of spontaneous alteration than vehicle-treated Tg mice, while the total number of arm entries did not differ between the groups. Furthermore, Congo red staining revealed that hAESCs injection reduced the number of amyloid plaques present in the brains of Tg mice. Finally, beta-secretase (BACE) activity was significantly decreased in Tg mice at 60 min after hAESCs injection. In this study, we found that intracerebral injection of hAESCs alleviated cognitive impairment in a Tg2576 mouse model of AD. Our results indicate that hAESCs injection reduced amyloid plaques caused by reduced BACE activity. These results indicate that hAESCs may be a useful therapeutic agent for the treatment of AD-related memory impairment.
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Doença de Alzheimer/terapia , Âmnio/citologia , Transplante de Células-Tronco , Células-Tronco/citologia , Doença de Alzheimer/etiologia , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Animais , Comportamento Animal , Modelos Animais de Doenças , Humanos , Imuno-Histoquímica , Aprendizagem em Labirinto , Camundongos , Camundongos Transgênicos , Placa Amiloide/metabolismo , Placa Amiloide/patologia , Transplante de Células-Tronco/métodos , Resultado do TratamentoRESUMO
Metal-coordination polymeric gels are interesting areas as organic/inorganic hybrid supramolecular materials. The bispicolylamine (BPA) based gelator (1) showed excellent gelation with typical fibrillar morphology in acetonitrile. Upon complexing 1 with Zn2+, complexes ([1 + Zn + ACN]2+ and [1 + zinc trifluoromethanesulfonate (ZnOTf)]+) with four coordination numbers were formed, which determine the gel structure significantly. A gel-sol transition was induced, driven by the ratio of the two metal complexes produced. Through nuclear magnetic resonance analysis, the driving forces in the gel formation (i.e., hydrogen-bonding and π-π stacking) were observed in detail. In the absence and the presence of Zn2+, the intermolecular hydrogen-bonds and π-π stacking were the primary driving forces in the gel formation, respectively. In addition, the supramolecular gels exhibited a monolayer lamellar structure irrespective of Zn2+. Conclusively, the gels' elasticity and viscosity reduced in the presence of Zn2+.
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Aminas/química , Géis/química , Ácidos Picolínicos/química , Zinco/química , Complexos de Coordenação , Ligação de Hidrogênio , Espectroscopia de Ressonância Magnética , Metais , Estrutura Molecular , Fenômenos Físicos , Polímeros/químicaRESUMO
OBJECTIVE: This study aimed to investigate the frequency of the anti-cyclic citrullinated peptide (anti-CCP) antibody in patients with psoriatic arthritis (PsA) and to assess its associations with clinical features of this disease. METHODS: The Medline, EMBASE, and Cochrane databases were searched for studies that examined anti-CCP antibodies in patients with PsA. Meta-analyses of the frequency of the anti-CCP antibody in these patients and its association with polyarthritis, bone erosion, dactylitis, and enthesitis were then performed. RESULTS: Fourteen studies with a combined total of 3291 patients with PsA met the inclusion criteria for this meta-analysis. The pooled overall frequency of anti-CCP antibodies was 9.8% (95% confidence interval [CI]â¯= 7.1-13.3, pâ¯< 0.001). Stratification by ethnicity showed that the anti-CCP antibody frequency was lower in Europeans than in non-Europeans (8.5% vs. 14.0%). The meta-analysis showed a significant association of the anti-CCP antibody with polyarthritis (odds ratio [OR]â¯= 4.390, 95% CIâ¯= 2.312-8.333, pâ¯< 0.001), bone erosion (ORâ¯= 2.800, 95% CIâ¯= 1.921-4.081, pâ¯< 0.001), and dactylitis (ORâ¯= 1.958, 95% CIâ¯= 1.340-2.861, pâ¯< 0.001). However, there was no association between this antibody and enthesitis. CONCLUSIONS: Our meta-analysis demonstrated that the overall frequency of the anti-CCP antibody was 9.8% in patients with PsA, and its presence was associated with increased risks of polyarthritis, bone erosion, and dactylitis, but not of enthesitis.
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Anticorpos Antiproteína Citrulinada/imunologia , Artrite Psoriásica , Febre Reumática/imunologia , Artrite Psoriásica/epidemiologia , Artrite Psoriásica/imunologia , Autoanticorpos , Humanos , Testes Imunológicos , Razão de Chances , Peptídeos Cíclicos , Febre Reumática/epidemiologiaRESUMO
We demonstrated the morphology transformation of co-assemblies based on terpyridine-based ligands (1R and 1S) possessing R- or S-alanine analogues and their platinum(II) complex (2R-Pt and 2S-Pt). The right-handed helical ribbon of the co-assembly formed with 0.5â equivalents of 2R-Pt to 1R was converted into the left-handed helical ribbon with 0.6â equivalents of 2R-Pt. The left-handed helical ribbon structure of the co-assembly became a tubular structure in the presence of 0.8-1.0â equivalents of 2R-Pt. The morphology transformation via helical inversion at the supramolecular level was due to an orientation change of the amide groups caused by non-covalent Ptâ â â Pt interactions between the terpyridine of 2R-Pt and that of 2R-Pt. This study provides insights into controlling the morphology of the transformation of helical ribbons into tubular structures through helicity inversion in co-assembled supramolecular nanostructures based on platinum(II) complexes.
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Finely controlled circularly polarized luminescence (CPL) supramolecular polymerization based on a tetraphenylethene core with four l- or d-alanine branch side chains (l-1 and d-1) in the solution state is presented, resulting from the tuning of mechanical stimulus. Weak, green emissions of l-1 and d-1 in tetrahydrofuran (THF) were converted into strong blue emissions by tuning the mechanical stimulus. The strong blue emissions were caused by an aggregation-induced emission (AIE) effect during the formation of a supramolecular polymer. Lag time in the supramolecular polymerization was drastically reduced by the mechanical stimulus, which was indicative of the acceleration of the supramolecular polymerization. A significant enhancement of circular dichroism (CD) and CPL signals of l-1 and d-1 was observed by tuning the rotational speed of the mechanical stimulus, implying that the chiral supramolecular polymerization was accelerated by the mechanical stimulus.
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We describe the role of amide groups formed by achiral and chiral moieties to study supramolecular helicity at the molecular level and the correlation between helicity and solvent properties at the supramolecular level. Using circular dichroism (CD) spectroscopy, we observed the CD spectra of supramolecular gel 1, which comprised a triphenylamine (TPA) core, terpyridine, and alanine moieties, formed in various solvents. The strong positive CD signals of supramolecular gel 1 formed in organic solvents, such as chloroform, tetrahydrofuran (THF), and dichloromethane, which have low polarity and a low acceptor number, were observed at 350â nm, indicating right-handed helicity. In contrast, the negative CD signals of supramolecular gel 1 formed in mixed DMSO/water (5:1 v/v), methanol, ethanol, and n-propanol were obtained at 350â nm, indicating left-handed helicity. These findings suggest that the helicity of supramolecular gel 1 was strongly influenced by the solvent properties. Indeed, atomic force spectroscopy images showed the right- and left-handed helicity of supramolecular gel 1 formed in various organic solvents, which was pure helicity.
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The defective fluorite-related Y3NbO7 host lattice was doped with Eu3+ ions to understand the influence of spark plasma sintering (SPS) process on this host lattice. The intrinsic disorder due to the occurrence of oxygen vacancies results in amorphous-type responses of the luminescent cations, and the spectral distribution varies as a function of the niobium content. Two spectral fingerprints of europium emissions were clearly enhanced. The correlation between luminescence, X-ray diffraction, and electron diffraction characterizations shows the existence of local inhomogeneity. Indeed, the particular nonequilibrium sintering conditions allowed pointing out a lack of miscibility within the Y3NbO7 solid solution domain. Thus, the SPS pellet is a composite of two extreme compositions. This phase demixing is mainly induced by the pressure coupled with a current effect that makes possible ionic migration in this Y3NbO7 ionic conductive matrix.
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BACKGROUD: Smoking is a risk factor for cardiovascular diseases as well as pulmonary dysfunction. In particular, adolescent smoking has been reported to have a higher latent risk for cardiovascular disease. Despite the risk to and vulnerability of adolescents to smoking, the mechanisms underlying the effects of acute nicotine exposure on adolescents remain unknown. This study therefore evaluated the mechanism underlying the effects of linalyl acetate on cardiovascular changes in adolescent rats with acute nicotine exposure. METHODS: Parameters analyzed included heart rate (HR), systolic blood pressure, lactate dehydrogenase (LDH) activity, vascular contractility, and nitric oxide levels. RESULTS: Compared with nicotine alone, those treated with nicotine plus 10 mg/kg (p = 0.036) and 100 mg/kg (p = 0.023) linalyl acetate showed significant reductions in HR. Moreover, the addition of 1 mg/kg (p = 0.011), 10 mg/kg (p = 0.010), and 100 mg/kg (p = 0.011) linalyl acetate to nicotine resulted in significantly lower LDH activity. Nicotine also showed a slight relaxation effect, followed by a sustained recontraction phase, whereas nicotine plus linalyl acetate or nifedipine showed a constant relaxation effect on contraction of mouse aorta (p < 0.001). Furthermore, nicotine-induced increases in nitrite levels were decreased by treatment with linalyl acetate (p < 0.001). CONCLUSIONS: Taken together, our findings suggest that linalyl acetate treatment resulted in recovery of cell damage and cardiovascular changes caused by acute nicotine-induced cardiovascular disruption. Our evaluation of the influence of acute nicotine provides potential insights into the effects of environmental tobacco smoke and suggests linalyl acetate as an available mitigating agent.