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2.
Artigo em Inglês | MEDLINE | ID: mdl-38719137

RESUMO

OBJECTIVE: Residual aortic dissection (AD) following DeBakey type I AD repair is associated with a high rate of adverse events that need additional intervention or surgery. This study aimed to identify clinical and early post-operative computed tomography (CT) imaging factors associated with adverse events in patients with type I AD after ascending aorta replacement. METHODS: This single centre, retrospective cohort study included consecutive patients with type I AD who underwent ascending aorta replacement from January 2011 to December 2017 and post-operative CT within 3 months. The primary outcome was AD related adverse events, defined as AD related death and re-operation due to aortic aneurysm or impending rupture. The location and size of the primary intimal tears, aortic diameter, and false lumen status were evaluated. Regression analyses were performed to identify factors associated with AD related adverse events. A decision tree model was used to classify patients as high or low risk. RESULTS: Of 103 participants (55.43 ± 13.94 years; 49.5% males), 24 (23.3%) experienced AD related adverse events. In multivariable Cox regression analysis, connective tissue disease (hazard ratio [HR] 15.33; p < .001), maximum aortic diameter ≥ 40 mm (HR 4.90; p < .001), and multiple (three or more) intimal tears (HR 7.12; p < .001) were associated with AD related adverse events. The 3 year cumulative survival free from AD related events was lower in the high risk group with aortic diameter ≥ 40 mm and multiple intimal tears (41.7% vs. 90.9%; p < .001). CONCLUSION: Early post-operative CT findings indicating a maximum aortic diameter ≥ 40 mm and multiple intimal tears may predict a higher risk of adverse events. These findings suggest the need for careful monitoring and more vigilant management approaches in these cases.

3.
Int Endod J ; 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38761098

RESUMO

Microorganisms are the primary aetiological factor of apical periodontitis. The goal of endodontic treatment is to prevent and eliminate the infection by removing the microorganisms. However, microbial biofilms and the complex root canal anatomy impair the disinfection process. Effective and precise endodontic therapy could potentially be achieved using advanced multifunctional technologies that have the ability to access hard-to-reach surfaces and perform simultaneous biofilm killing, removal, and detection of microorganisms. Advances in microrobotics are providing novel therapeutic and diagnostic opportunities with high precision and efficacy to address current biofilm-related challenges in biomedicine. Concurrently, multifunctional magnetic microrobots have been developed to overcome the disinfection challenges of current approaches to disrupt, kill, and retrieve biofilms with the goal of enhancing the efficacy and precision of endodontic therapy. This article reviews the recent advances of microrobotics in healthcare and particularly advances to overcome disinfection challenges in endodontics, and provides perspectives for future research in the field.

5.
Comput Biol Med ; 175: 108494, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38688124

RESUMO

BACKGROUND & OBJECTIVE: Aortic dissection (AD) is a serious condition requiring rapid and accurate diagnosis. In this study, we aimed to improve the diagnostic accuracy of AD by presenting a novel method for aortic segmentation in computed tomography images that uses a combination of a transformer and a UNet cascade network with a Zoom-Out and Zoom-In scheme (ZOZI-seg). METHODS: The proposed method segments each compartment of the aorta, comprising the true lumen (TL), false lumen (FL), and thrombosis (TH) using a cascade strategy that captures both the global context (anatomical structure) and the local detail texture based on the dynamic patch size with ZOZI schemes. The ZOZI-seg model has a two-stage architecture using both a "3D transformer for panoptic context-awareness" and a "3D UNet for localized texture refinement." The unique ZOZI strategies for patching were demonstrated in an ablation study. The performance of our proposed ZOZI-seg model was tested using a dataset from Asan Medical Center and compared with those of existing models such as nnUNet and nnFormer. RESULTS: In terms of segmentation accuracy, our method yielded better results, with Dice similarity coefficients (DSCs) of 0.917, 0.882, and 0.630 for TL, FL, and TH, respectively. Furthermore, we indirectly compared our model with those in previous studies using an external dataset to evaluate its robustness and generalizability. CONCLUSIONS: This approach may help in the diagnosis and treatment of AD in different clinical situations and provide a strong basis for further research and clinical applications.


Assuntos
Dissecção Aórtica , Tomografia Computadorizada por Raios X , Humanos , Dissecção Aórtica/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Algoritmos
6.
J Mater Chem B ; 12(20): 4935-4944, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38683039

RESUMO

The oral cavity, a warm and moist environment, is prone to the proliferation of microorganisms like Candida albicans (C. albicans), which forms robust biofilms on biotic and abiotic surfaces, leading to challenging infections. These biofilms are resistant to conventional treatments due to their resilience against antimicrobials and immune responses. The dynamic nature of the oral cavity, including the salivary flow and varying surface properties, complicates the delivery of therapeutic agents. To address these challenges, we introduce dendritic microparticles engineered for enhanced adhesion to dental surfaces and effective delivery of antifungal agents and antibiofilm enzymes. These microparticles are fabricated using a water-in-oil-in-water emulsion process involving a blend of poly(lactic-co-glycolic acid) (PLGA) random copolymer (RCP) and PLGA-b-poly(ethylene glycol) (PLGA-b-PEG) block copolymer (BCP), resulting in particles with surface dendrites that exhibit strong adhesion to oral surfaces. Our study demonstrates the potential of these adhesive microparticles for oral applications. The adhesion tests on various oral surfaces, including dental resin, hydroxyapatite, tooth enamel, and mucosal tissues, reveal superior adhesion of these microparticles compared to conventional spherical ones. Furthermore, the release kinetics of nystatin from these microparticles show a sustained release pattern that can kill C. albicans. The biodegradation of these microparticles on tooth surfaces and their efficacy in preventing fungal biofilms have also been demonstrated. Our findings highlight the effectiveness of adhesive microparticles in delivering therapeutic agents within the oral cavity, offering a promising approach to combat biofilm-associated infections.


Assuntos
Antifúngicos , Biofilmes , Candida albicans , Propriedades de Superfície , Biofilmes/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Candida albicans/fisiologia , Antifúngicos/farmacologia , Antifúngicos/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Humanos , Boca/microbiologia , Adesivos/química , Adesivos/farmacologia , Tamanho da Partícula , Polietilenoglicóis/química , Portadores de Fármacos/química
7.
Adv Mater ; : e2314274, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38647521

RESUMO

A gate stack that facilitates a high-quality interface and tight electrostatic control is crucial for realizing high-performance and low-power field-effect transistors (FETs). However, when constructing conventional metal-oxide-semiconductor structures with two-dimensional (2D) transition metal dichalcogenide channels, achieving these requirements becomes challenging due to inherent difficulties in obtaining high-quality gate dielectrics through native oxidation or film deposition. Here, a gate-dielectric-less device architecture of van der Waals Schottky gated metal-semiconductor FETs (vdW-SG MESFETs) using a molybdenum disulfide (MoS2) channel and surface-oxidized metal gates such as nickel and copper is reported. Benefiting from the strong SG coupling, these MESFETs operate at remarkably low gate voltages, <0.5 V. Notably, they also exhibit Boltzmann-limited switching behavior featured by a subthreshold swing of ≈60 mV dec-1 and negligible hysteresis. These ideal FET characteristics are attributed to the formation of a Fermi-level (EF) pinning-free gate stack at the Schottky-Mott limit. Furthermore, authors experimentally and theoretically confirm that EF depinning can be achieved by suppressing both metal-induced and disorder-induced gap states at the interface between the monolithic-oxide-gapped metal gate and the MoS2 channel. This work paves a new route for designing high-performance and energy-efficient 2D electronics.

8.
J Am Chem Soc ; 146(12): 8320-8326, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38489763

RESUMO

One-dimensional (1D) Heisenberg antiferromagnets are of great interest due to their intriguing quantum phenomena. However, the experimental realization of such systems with large spin S remains challenging because even weak interchain interactions induce long-range ordering. In this study, we present an ideal 1D S = 5/2 spin chain antiferromagnet achieved through a multistep topochemical route involving dehydration and rehydration. By desorbing three water molecules from (2,2'-bpy)FeF3(H2O)·2H2O (2,2'-bpy = 2,2'-bipyridyl) at 150 °C and then intercalating two water molecules at room temperature (giving (2,2'-bpy)FeF3·2H2O 1), the initially isolated FeF3ON2 octahedra combine to form corner-sharing FeF4N2 octahedral chains, which are effectively separated by organic and added water molecules. Mössbauer spectroscopy reveals significant dynamical fluctuations down to 2.7 K, despite the presence of strong intrachain interactions. Moreover, results from electron spin resonance (ESR) and heat capacity measurements indicate the absence of long-range order down to 0.5 K. This controlled topochemical dehydration/rehydration approach is further extended to (2,2'-bpy)CrF3·2H2O with S = 3/2 1D chains, thus opening the possibility of obtaining other low-dimensional spin lattices.

9.
Korean J Radiol ; 25(4): 331-342, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38528691

RESUMO

The Asian Society of Cardiovascular Imaging-Practical Tutorial (ASCI-PT) is an instructional initiative of the ASCI School designed to enhance educational standards. In 2021, the ASCI-PT was convened with the goal of formulating a consensus statement on the assessment of coronary stenosis and coronary plaque using coronary CT angiography (CCTA). Nineteen experts from four countries conducted thorough reviews of current guidelines and deliberated on eight key issues to refine the process and improve the clarity of reporting CCTA findings. The experts engaged in both online and on-site sessions to establish a unified agreement. This document presents a summary of the ASCI-PT 2021 deliberations and offers a comprehensive consensus statement on the evaluation of coronary stenosis and coronary plaque in CCTA.


Assuntos
Doença da Artéria Coronariana , Estenose Coronária , Placa Aterosclerótica , Humanos , Angiografia por Tomografia Computadorizada , Valor Preditivo dos Testes , Estenose Coronária/diagnóstico por imagem , Placa Aterosclerótica/diagnóstico por imagem , Angiografia Coronária
10.
Cardiol Young ; : 1-14, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38525659

RESUMO

BACKGROUND: The increased survival rate among individuals with CHD has sparked interest in their transition to adult healthcare. Although there is a general agreement on the importance of transition interventions, the empirical evidence supporting them is insufficient. Therefore, this study aimed to conduct a systematic review and meta-analysis of transition interventions for adult healthcare in adolescents and young adults. METHODS AND RESULTS: A literature search was conducted for studies comparing the quantitative effects of transition interventions with control groups, published up to March 15, 2023, in major databases (CENTRAL, Embase, PubMed, Web of Science, CINAHL, KISS, and KMbase), major clinical trial registries, academic journal sites related to the topic, and grey literature databases. Ten studies involving a total of 1,297 participants were identified. Transition interventions proved effective in enhancing disease-related knowledge (Hedge's g = 0.89, 95% CI = 0.29-1.48) and self-management (Hedge's g = 0.67, 95% CI = 0.38-0.95), as well as reducing loss to follow-up (OR = 0.41, 95% CI = 0.22-0.77). The certainty of evidence for the estimated values of each major outcome was low or very low. CONCLUSIONS: This study supports the implementation of transition interventions by demonstrating that they can improve patients' disease knowledge and self-management, while also promoting treatment continuity. However, since the available data on transition interventions for adolescents and young adults with CHD remain limited, the widespread adoption of structured transition interventions in the future may alter the conclusions of this study. REGISTRATION: URL: https://www.crd.york.ac.uk/PROSPERO. Unique identifier: CRD42023399026.

11.
Genet Epidemiol ; 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38472164

RESUMO

Genome-wide association studies (GWAS) have provided an abundance of information about the genetic variants and their loci that are associated to complex traits and diseases. However, due to linkage disequilibrium (LD) and noncoding regions of loci, it remains a challenge to pinpoint the causal genes. Gene network-based approaches, paired with network diffusion methods, have been proposed to prioritize causal genes and to boost statistical power in GWAS based on the assumption that trait-associated genes are clustered in a gene network. Due to the difficulty in mapping trait-associated variants to genes in GWAS, this assumption has never been directly or rigorously tested empirically. On the other hand, whole exome sequencing (WES) data focuses on the protein-coding regions, directly identifying trait-associated genes. In this study, we tested the assumption by leveraging the recently available exome-based association statistics from the UK Biobank WES data along with two types of networks. We found that almost all trait-associated genes were significantly more proximal to each other than randomly selected genes within both networks. These results support the assumption that trait-associated genes are clustered in gene networks, which can be further leveraged to boost the power of GWAS such as by introducing less stringent p value thresholds.

14.
J Korean Soc Radiol ; 85(1): 210-214, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38362385

RESUMO

Interventricular membranous septal aneurysms are rare. Since these aneurysms can lead to complications such as obstruction of right ventricular outflow and thromboembolism, the detection of this aneurysm has clinical significance. Herein, we report a case of an interventricular membranous septal aneurysm with an internal thrombus thought to be the cause of a cerebral infarction.

15.
Mol Pharm ; 21(3): 1353-1363, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38282332

RESUMO

Very late antigen-4 (VLA4; CD49d) is a promising immune therapy target in treatment-resistant leukemia and multiple myeloma, and there is growing interest in repurposing the humanized monoclonal antibody (Ab), natalizumab, for this purpose. Positron emission tomography with radiolabeled Abs (immuno-PET) could facilitate this effort by providing information on natalizumab's in vivo pharmacokinetic and target delivery properties. In this study, we labeled natalizumab with 89Zr specifically on sulfhydryl moieties via maleimide-deferoxamine conjugation. High VLA4-expressing MOLT4 human T cell acute lymphoblastic leukemia cells showed specific 89Zr-natalizumab binding that was markedly blocked by excess Ab. In nude mice bearing MOLT4 tumors, 89Zr-natalizumab PET showed high-contrast tumor uptake at 7 days postinjection. Biodistribution studies confirmed that uptake was the highest in MOLT4 tumors (2.22 ± 0.41%ID/g) and the liver (2.33 ± 0.76%ID/g), followed by the spleen (1.51 ± 0.42%ID/g), while blood activity was lower at 1.12 ± 0.21%ID/g. VLA4-specific targeting in vivo was confirmed by a 58.1% suppression of tumor uptake (0.93 ± 0.15%ID/g) when excess Ab was injected 1 h earlier. In cultured MOLT4 cells, short-term 3 day exposure to the proteasome inhibitor bortezomib (BTZ) did not affect the α4 integrin level, but BTZ-resistant cells that survived the treatment showed increased α4 integrin expression. When the effects of BTZ treatment were tested in mice, there was no change of the α4 integrin level or 89Zr-natalizumab uptake in MOLT4 leukemia tumors, which underscores the complexity of tumor VLA4 regulation in vivo. In conclusion, 89Zr-natalizumab PET may be useful for noninvasive monitoring of tumor VLA4 and may assist in a more rational application of Ab-based therapies for hematologic malignancies.


Assuntos
Integrina alfa4beta1 , Leucemia , Humanos , Animais , Camundongos , Natalizumab/uso terapêutico , Cisteína , Integrina alfa4 , Camundongos Nus , Distribuição Tecidual , Linhagem Celular Tumoral , Tomografia por Emissão de Pósitrons/métodos , Zircônio/química
16.
Biochemistry ; 63(3): 355-366, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38206111

RESUMO

Inferring the historical and biophysical causes of diversity within protein families is a complex puzzle. A key to unraveling this problem is characterizing the rugged topography of sequence-function adaptive landscapes. Using biochemical data from a 29 = 512 combinatorial library of tobacco 5-epi-aristolochene synthase (TEAS) mutants engineered to make the native major product of Egyptian henbane premnaspirodiene synthase (HPS) and a complementary 512 mutant HPS library, we address the question of how product specificity is controlled. These data sets reveal that HPS is far more robust and resistant to mutations than TEAS, where most mutants are promiscuous. We also combine experimental data with a sequence Potts Hamiltonian model and direct coupling analysis to quantify mutant fitness. Our results demonstrate that the Hamiltonian captures variation in product outputs across both libraries, clusters native family members based on their substrate specificities, and exposes the divergent catalytic roles of couplings between the catalytic and noncatalytic domains of TEAS versus HPS. Specifically, we found that the role of the interdomain connectivities in specifying product output is more important in TEAS than connectivities within the catalytic domain. Despite being 75% identical, this property is not shared by HPS, where connectivities within the catalytic domain are more important for specificity. By solving the X-ray crystal structure of HPS, we assessed structural bases for their interdomain network differences. Last, we calculate the product profile Shannon entropies of the two libraries, which showcases that site-site connectivities also play divergent roles in catalytic accuracy.


Assuntos
Alquil e Aril Transferases , Catálise , Domínio Catalítico , Mutação
17.
Adv Mater ; 36(10): e2300320, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37141008

RESUMO

Fungal pathogens have been designated by the World Health Organization as microbial threats of the highest priority for global health. It remains a major challenge to improve antifungal efficacy at the site of infection while avoiding off-target effects, fungal spreading, and drug tolerance. Here, a nanozyme-based microrobotic platform is developed that directs localized catalysis to the infection site with microscale precision to achieve targeted and rapid fungal killing. Using electromagnetic field frequency modulation and fine-scale spatiotemporal control, structured iron oxide nanozyme assemblies are formed that display tunable dynamic shape transformation and catalysis activation. The catalytic activity varies depending on the motion, velocity, and shape providing controllable reactive oxygen species (ROS) generation. Unexpectedly, nanozyme assemblies bind avidly to fungal (Candida albicans) surfaces to enable concentrated accumulation and targeted ROS-mediated killing in situ. By exploiting these tunable properties and selective binding to fungi, localized antifungal activity is achieved using in vivo-like cell spheroid and animal tissue infection models. Structured nanozyme assemblies are directed to Candida-infected sites using programmable algorithms to perform precisely guided spatial targeting and on-site catalysis resulting in fungal eradication within 10 min. This nanozyme-based microrobotics approach provides a uniquely effective and targeted therapeutic modality for pathogen elimination at the infection site.


Assuntos
Antifúngicos , Micoses , Animais , Antifúngicos/química , Antifúngicos/metabolismo , Antifúngicos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Candida albicans/metabolismo , Modelos Animais
18.
J Am Coll Radiol ; 21(3): 505-514, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37778572

RESUMO

OBJECTIVE: Academic radiology is essential for advancing medical knowledge, improving patient care, and leading professional organizations. Any shortage of academic faculty affects the ability to provide quality education in radiology, conduct research, and advance the field. In this study, we aimed to identify contributors to the challenges faced by academic radiology in Korea and compare the work burden, career satisfaction, and burnout between academic radiology and private practice. METHODS: A Google survey of members of the Korean Society of Radiology, conducted between August 19, 2022 and August 31, 2022, attracted responses from 642 radiologists, including 511 board-certified radiologists and 131 radiologist trainees. The survey assessed career satisfaction, burnout, and reasons for working in academia and frustrations with an academic career. RESULTS: Of the responding academic radiologists, 53% were located in Seoul, and of the responding private practice radiologists, 71% were located in regions outside Seoul. The reported volume of image readings per month (CT and/or MRI) was higher for academic radiologists than for private practice radiologists, but no significant difference in the time taken to complete the readings was evident between the two groups. Compared with private practice radiologists, academic radiologists required more time for education, clinical conferences, and additional nonclinical tasks. Lower scores for career satisfaction and higher scores for burnout were reported by academic radiologists, compared with private practice radiologists. DISCUSSION: The field of academic radiology in Korea faces challenges because of a faculty shortage. To prevent the collapse of education in radiology, interventions must address the identified contributors to this shortage, while increasing career satisfaction and reducing burnout among academic radiologists.


Assuntos
Esgotamento Profissional , Radiologia , Humanos , Radiologia/educação , Radiologistas , Radiografia , República da Coreia
19.
Trends Biotechnol ; 42(4): 479-495, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37968157

RESUMO

The eradication of drug-resistant microbial biofilms remains an unresolved global health challenge. Small-scale robotics are providing innovative therapeutic and diagnostic approaches with high precision and efficacy. These approaches are rapidly moving from proof-of-concept studies to translational biomedical applications using ex vivo, animal, and clinical models. Here, we discuss the fundamental and translational aspects of how microrobots target the infection sites to disrupt the structural and functional traits of biofilms and their antimicrobial resistance mechanisms. We emphasize current approaches of mechanochemical disruption and on-site drug delivery that are supported by in vivo models and preclinical testing, while also highlighting diagnostics potential. We also discuss clinical translation challenges and provide perspectives for development of microrobotics approaches to combat biofilm infections and biofouling in humans.


Assuntos
Biofilmes , Incrustação Biológica , Animais , Humanos , Sistemas de Liberação de Medicamentos , Antibacterianos
20.
Am Heart J ; 269: 167-178, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38123045

RESUMO

BACKGROUND: The risks of leaflet thrombosis and the associated cerebral thromboembolism are unknown according to different anticoagulation dosing after transcatheter aortic valve replacement (TAVR). The aim was to evaluate the incidence of leaflet thrombosis and cerebral thromboembolism between low-dose (30 mg) or standard-dose (60 mg) edoxaban and dual antiplatelet therapy (DAPT) after TAVR. METHODS: In this prespecified subgroup analysis of the ADAPT-TAVR trial, the primary endpoint was the incidence of leaflet thrombosis on 4-dimensional computed tomography at 6-months. Key secondary endpoints were new cerebral lesions on brain magnetic resonance imaging and neurological and neurocognitive dysfunction. RESULTS: Of 229 patients enrolled in this study, 118 patients were DAPT group and 111 were edoxaban group (43 [39.1%] 60 mg vs 68 [61.3%] 30 mg). There was a significantly lower incidence of leaflet thrombosis in the standard-dose edoxaban group than in the DAPT group (2.4% vs 18.3%; odds ratio [OR] 0.11; 95% confidence interval [CI], 0.01-0.55; P = .03). However, no significant difference was observed between low-dose edoxaban and DAPT (15.0% vs 18.3%; OR 0.79; 95% CI, 0.32-1.81; P = .58). Irrespective of different antithrombotic regiments, the percentages of patients with new cerebral lesions on brain MRI and worsening neurological or neurocognitive function were not significantly different. CONCLUSIONS: In patients without an indication for anticoagulation after TAVR, the incidence of leaflet thrombosis was significantly lower with standard-dose edoxaban but not with low-dose edoxaban, as compared with DAPT. However, this differential effect of edoxaban on leaflet thrombosis was not associated with a reduction of new cerebral thromboembolism and neurological dysfunction.


Assuntos
Estenose da Valva Aórtica , Piridinas , Tiazóis , Tromboembolia , Trombose , Substituição da Valva Aórtica Transcateter , Humanos , Substituição da Valva Aórtica Transcateter/efeitos adversos , Substituição da Valva Aórtica Transcateter/métodos , Inibidores da Agregação Plaquetária , Valva Aórtica/cirurgia , Resultado do Tratamento , Tromboembolia/epidemiologia , Tromboembolia/etiologia , Tromboembolia/prevenção & controle , Trombose/epidemiologia , Trombose/etiologia , Trombose/prevenção & controle , Anticoagulantes/uso terapêutico , Estenose da Valva Aórtica/complicações
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