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1.
J Org Chem ; 89(7): 4503-4511, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38502929

RESUMO

Tetrahydroisoquinoline (THIQ) derivatives stand out as a promising class of compounds due to their diverse range of biological activities, making them particularly valuable in drug discovery. To enhance their structural diversity, an Rh-catalyzed denitrogenative annulation method has been introduced for synthesizing these derivatives. An intriguing aspect of this method is the ability of the Brønsted acid to prevent further annulation while facilitating the production of the desired THIQ derivatives, achieving impressive yields of up to 86%. This synthetic approach was subsequently leveraged to create an analogue of cyclocelabenzine, a compound showing potential as an anti-inflammatory agent.

2.
Int J Med Sci ; 21(7): 1257-1264, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38818460

RESUMO

Background: Ferroptosis is an iron-driven cell-death mechanism that plays a central role in various diseases. Recent studies have suggested that baicalein inhibits ferroptosis, making it a promising therapeutic candidate. Materials and Methods: Fibroblast cultures were treated with different agents to determine the effects of baicalein on ferroptosis. Ferroptosis-related gene expression, lipid peroxidation, and post-treatment cellular structural changes were measured using real-time quantitative polymerase chain reaction, C11-BODIPY dye, and transmission electron microscopy, respectively. Results: Baicalein significantly inhibited rat sarcoma virus selective lethal 3-induced ferroptosis in fibroblasts. Moreover, in baicalein-treated groups, reduced ferroptosis-related gene expression, decreased lipid peroxidation, and maintained cell structure was observed when compared with those of the controls. Discussion: The ability of baicalein to counteract RSL3-induced ferroptosis underscores its potential protective effects, especially in diseases characterized by oxidative stress and iron overload in fibroblasts. Conclusion: Baicalein may serve as a potent therapeutic agent against conditions in which ferroptosis is harmful. The compound's efficacy in halting RSL3-triggered ferroptosis in fibroblasts paves the way for further in vivo experiments and clinical trials.


Assuntos
Ferroptose , Fibroblastos , Flavanonas , Animais , Humanos , Ratos , Carbolinas , Ferroptose/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Flavanonas/farmacologia , Flavanonas/uso terapêutico , Ferro/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos
3.
Int J Med Sci ; 21(7): 1302-1306, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38818474

RESUMO

Background: Hyperopia is a significant refractive error in children, often leading to vision impairment. This study aimed to investigate whether partial or full spectacle correction is benefit for hyperopia in preschool-aged children. Methods: A retrospective study was conducted on hyperopic children visited to teaching medical center outpatient clinic between October 2011 and October 2018, and were categorized into three groups: full correction, overcorrection, and undercorrection. The study was approved by the institutional ethical committee of Tri-Service General Hospital. Results: Following a minimum of one-year follow-up period, no statistically significant differences were observed in best-corrected visual acuity (BCVA) among children receiving full, over, or under spectacle correction. Notably, the overcorrection group exhibited a significant reduction in spherical equivalent (SE) compared to both the full and under correction groups, indicating a better SE with spectacle overcorrection. Conclusions: Spectacle overcorrection may offer potential benefits for enhancing SE in preschool children with hyperopia. Nevertheless, further investigation through randomized controlled trials is warranted to establish the validity of this approach and its impact on visual outcomes in this hyperopic pediatric population.


Assuntos
Óculos , Hiperopia , Acuidade Visual , Humanos , Hiperopia/terapia , Hiperopia/fisiopatologia , Estudos Retrospectivos , Pré-Escolar , Feminino , Masculino , Refração Ocular/fisiologia , Criança , Resultado do Tratamento , Seguimentos
4.
Proc Natl Acad Sci U S A ; 118(4)2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33408129

RESUMO

Spatially concentrating and manipulating biotherapeutic agents within the circulatory system is a longstanding challenge in medical applications due to the high velocity of blood flow, which greatly limits drug leakage and retention of the drug in the targeted region. To circumvent the disadvantages of current methods for systemic drug delivery, we propose tornado-inspired acoustic vortex tweezer (AVT) that generates net forces for noninvasive intravascular trapping of lipid-shelled gaseous microbubbles (MBs). MBs are used in a diverse range of medical applications, including as ultrasound contrast agents, for permeabilizing vessels, and as drug/gene carriers. We demonstrate that AVT can be used to successfully trap MBs and increase their local concentration in both static and flow conditions. Furthermore, MBs signals within mouse capillaries could be locally improved 1.7-fold and the location of trapped MBs could still be manipulated during the initiation of AVT. The proposed AVT technique is a compact, easy-to-use, and biocompatible method that enables systemic drug administration with extremely low doses.

5.
Skeletal Radiol ; 53(6): 1111-1118, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38057435

RESUMO

OBJECTIVE: To investigate and quantify age-related changes in lower limb muscle stiffness in typically developing children and adolescents using acoustic radiation force impulse shear wave elastography. MATERIALS AND METHODS: Shear wave velocities of bilateral rectus femoris, tibialis anterior, and medial gastrocnemius muscles at rest were obtained in typically developing children and adolescents aged 3 to 18 years. The participants were classified into three age groups: Group 1 (children), 3 to 7 years old; Group 2, 8 to 12 (pre-adolescent); and Group 3 (adolescent), 13 to 18. The shear wave velocities of muscle were compared across the three age groups, as well as compared between right- and left-side limbs. The correlation between shear wave velocities and body weight or body mass index was assessed. RESULTS: Of the 47 participants, 21 were in Group 1, 17 in Group 2, and 9 in Group 3. There were no significant differences among the three age groups' shear wave velocities of bilateral lower limb muscles, and no significant differences between right and left sides. There was no correlation between muscle stiffness and body weight or body mass index. CONCLUSION: The present pilot study applied acoustic radiation force impulse shear wave elastography to quantify lower limb muscle stiffness in typically developing children and adolescents aged 3 to 18 years, suggesting no marked change in muscle stiffness occurs as they develop.


Assuntos
Técnicas de Imagem por Elasticidade , Criança , Humanos , Adolescente , Pré-Escolar , Projetos Piloto , Músculo Esquelético/diagnóstico por imagem , Extremidade Inferior/diagnóstico por imagem , Peso Corporal , Acústica
6.
J Formos Med Assoc ; 123 Suppl 1: S61-S69, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37061399

RESUMO

Coronavirus disease 2019 (COVID-19) has caused tremendous morbidity and mortality worldwide. The large number of post-COVID survivors has drawn attention to the management of post-COVID condition, known as long COVID. This review examines current knowledge of long COVID, regarding its epidemiology, mechanism, and clinical presentations in both adults and children. We also review the rehabilitation principles, modules, and effects, and share Taiwan's efforts to provide a top-down, nationwide care framework for long COVID patients. Dyspnea, chronic cough, and fatigue are the most commonly reported symptoms in the first 6 months after infection, but cognitive impairment and psychological symptoms may persist beyond this time. Several possible mechanisms behind these symptoms were proposed, but remained unconfirmed. These symptoms negatively impact individuals' function, activities, participation and quality of life. Rehabilitation is a key element of management to achieve functional improvement. Early management should start with comprehensive evaluation and identification of red flags. Exercise-based therapy, an essential part of management of long COVID, can be conducted with different modules, including telerehabilitation. Post-exertional symptom exacerbation and orthostatic hypotension should be carefully monitored during exercise. Randomized control trials with a large sample size are needed to determine the optimal timing, dosage, and modules.


Assuntos
COVID-19 , Síndrome de COVID-19 Pós-Aguda , Adulto , Criança , Humanos , Qualidade de Vida , Terapia por Exercício , Dispneia
7.
J Magn Reson Imaging ; 58(3): 894-904, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36573963

RESUMO

BACKGROUND: Contrast-enhanced computed tomography angiography (CTA) and magnetic resonance angiography (MRA) are the primary modalities to assess donors' vessels before transplant surgery. Radiation and contrast medium are potentially harmful to donors. PURPOSE: To compare the image quality and visualization scores of hepatic arteries on CTA and balanced steady-state free-precession (bSSFP) non-contrast-enhanced MRA (NC-MRA), and to evaluate if bSSFP NC-MRA can potentially be a substitute for CTA. STUDY TYPE: Prospective. POPULATION: Fifty-six consecutive potential living-related liver donors (30.9 ± 8.4 years; 31 men). FIELD STRENGTH/SEQUENCE: 1.5T; four bSSFP NC-MRA sequences: respiratory-triggered (Inhance inflow inversion recovery [IFIR]) and three breath-hold (BH); and CTA. ASSESSMENT: The artery-to-liver contrast (Ca-l) was quantified. Three radiologists independently assigned visualization scores using a four-point scale to potential origins, segments, and branches of the hepatic arteries, determined the anatomical variants based on Hiatt's classification, and assessed the image quality of NC-MRA sequences. STATISTICAL TESTS: Fleiss' kappa to evaluate the readers' agreement. Repeat measured ANOVA or Friedman test to compare Ca-l of each NC-MRA. Friedman test to compare overall image quality and visualization scores; post hoc analysis using Wilcoxon signed-rank test. P-value <0.05 was considered statistically significant. RESULTS: Inhance IFIR Ca-l was significantly higher than all BH bSSFP Ca-l (0.56 [0.45-0.64] vs. 0.37 [0.29-0.47] to 0.41 [0.23-0.51]). Overall image quality score of BH bSSFP TI1200 was significantly higher than other NC-MRA (4 [4-4] vs. 4 [3 to 4-4]). The median visualization scores of almost all arteries on CTA were significantly higher than on NC-MRA (4 [3 to 4-4] vs. 1 [1-2] to 4 [4-4]). The median visualization scores were all 4 [4-4 ] on Inhance IFIR with >92.3% observed scores ≥3, except the segment 4 branch (3 [1-4], 53.6%). The identification rates of arterial variants were 92.9%-97% on Inhance IFIR. DATA CONCLUSIONS: Although CTA is superior to the NC-MRA, all NC-MRA depict the donor arterial anatomy well. Inhance IFIR can potentially be an alternative image modality for CTA to evaluate the arterial variants of living donors. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.


Assuntos
Meios de Contraste , Doadores Vivos , Masculino , Humanos , Estudos Prospectivos , Fígado/diagnóstico por imagem , Fígado/irrigação sanguínea , Angiografia por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X , Reprodutibilidade dos Testes
8.
Int J Behav Nutr Phys Act ; 20(1): 44, 2023 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-37069626

RESUMO

BACKGROUND: Promoting physical activity (PA) in different populations experiencing sleep disturbance may increase population PA levels and improve sleep. This scoping review aimed to examine the effect of various PA intervention strategies on sleep across different populations, identify key sleep outcomes, and analyze knowledge gaps by mapping the relevant literature. METHODS: For this study, we systematically searched articles published till March 2022 from PubMed, Web of Science, Cochrane Library, and Embase databases for randomized clinical trials (RCTs) regarding the effect of physical activity on sleep. Two authors extracted key data and descriptively analyzed the data. Thematic analysis was used to categorize the results into themes by all authors. Arksey and O'Malley's scoping review framework was used to present the findings. RESULTS: Twenty-one randomized controlled trials out of 3052 studies were finally included with 3677 participants (2852 females (78%)). Five trials were conducted in healthy working-age adults with sleep disturbance but without the diagnosis of insomnia, five in healthy older adults, two in perinatal women, four in patients with cancer, three in mental illness related subjects, and another two in other disease-related areas. PA interventions were diverse, including walking, resistance training, aerobic exercise, housework, water exercise, basketball, smartphone/tablet "apps", web, online videos or wearable actigraphy, and self-determined exercise. Three major themes were identified: (1) Sleep environment may be important to address prior to instituting PA interventions, (2) All types of PA were effective for improving sleep in all populations studied, (3) Self-tolerated PA is safe for improving sleep in the elderly and in co-morbid or perinatal populations. CONCLUSIONS: PA is effective and safe for improving sleep in both healthy and co-morbid populations with sleep disturbance by increasing daily activity levels using a variety of strategies, even low intensity, such as housekeeping, sit-to-stand repetitions, along with encouraging PA through web pages, videos, and self-goal setting apps. In addition, this scoping review identifies the need for further therapeutic research and future exploration in populations with sleep initiation or sleep maintenance disturbance.


Assuntos
Exercício Físico , Neoplasias , Idoso , Feminino , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Sono , Caminhada
9.
J Biol Chem ; 296: 100809, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34023382

RESUMO

Oligosaccharyltransferase (OST) catalyzes the central step in N-linked protein glycosylation, the transfer of a preassembled oligosaccharide from its lipid carrier onto asparagine residues of secretory proteins. The prototypic hetero-octameric OST complex from the yeast Saccharomyces cerevisiae exists as two isoforms that contain either Ost3p or Ost6p, both noncatalytic subunits. These two OST complexes have different protein substrate specificities in vivo. However, their detailed biochemical mechanisms and the basis for their different specificities are not clear. The two OST complexes were purified from genetically engineered strains expressing only one isoform. The kinetic properties and substrate specificities were characterized using a quantitative in vitro glycosylation assay with short peptides and different synthetic lipid-linked oligosaccharide (LLO) substrates. We found that the peptide sequence close to the glycosylation sequon affected peptide affinity and turnover rate. The length of the lipid moiety affected LLO affinity, while the lipid double-bond stereochemistry had a greater influence on LLO turnover rates. The two OST complexes had similar affinities for both the peptide and LLO substrates but showed significantly different turnover rates. These data provide the basis for a functional analysis of the Ost3p and Ost6p subunits.


Assuntos
Hexosiltransferases/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Hexosiltransferases/química , Cinética , Proteínas de Membrana/química , Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismo , Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/química , Especificidade por Substrato
10.
Anal Chem ; 94(48): 16579-16586, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36414482

RESUMO

Chlorine, as a dual-use chemical, is an essential industrial chemical which has been used as a chemical weapon in the past due to its toxicity and availability. The retrospective verification of chlorine intoxication is often especially challenging, and unambiguous markers are still missing. In this study, the effects of different chlorinating and oxidizing agents on human hair were investigated. Samples were exposed to a variety of chlorinating chemicals for a short time and then completely hydrolyzed by a HBr solution to break down their keratin proteins into individual amino acids. After derivatization and targeted liquid chromatography-mass spectrometry analysis, 3-chlorotyrosine and 3,5-dichlorotyrosine were unambiguously identified from human hair exposed to chlorine, hypochlorite, and sulfuryl chloride. Our results show long-term stability of these markers in the biological matrix, as the chlorotyrosines can still be found 10 months post-exposure at the same levels. Finally, an untargeted analysis was able to discriminate between some of the different intoxicants.


Assuntos
Cloro , Cabelo , Humanos , Cloro/química , Estudos Retrospectivos , Espectrometria de Massas , Cabelo/metabolismo , Biomarcadores
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