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1.
J Dent Sci ; 19(3): 1595-1600, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39035269

RESUMEN

Background/purpose: Rapid advancements in AI technology have led to significant interest in its application across various fields, including medicine and dentistry. This study aimed to assess the capabilities of ChatGPT-4V with image recognition in answering image-based questions from the Japanese National Dental Examination (JNDE) to explore its potential as an educational support tool for dental students. Materials and methods: The dataset used questions from the JNDE, which was conducted in January 2023, with a focus on image-related queries. ChatGPT-4V was utilized, and standardized prompts, question texts, and images were input. Data and statistical analyses were conducted using Qlik Sense® and GraphPad Prism. Results: The overall correct response rate of ChatGPT-4V for image-based JNDE questions was 35.0 %. The correct response rates were 57.1 % for compulsory questions, 43.6 % for general questions, and 28.6 % for clinical practical questions. In specialties like Dental Anesthesiology and Endodontics, ChatGPT-4V achieved correct response rates above 70 %, while response rates for Orthodontics and Oral Surgery were lower. A higher number of images in questions was correlated with lower accuracy, suggesting an impact of the number of images on correct and incorrect responses. Conclusion: While innovative, ChatGPT-4V's image recognition feature exhibited limitations, especially in handling image-intensive and complex clinical practical questions, and is not yet fully suitable as an educational support tool for dental students at its current stage. Further technological refinement and re-evaluation with a broader dataset are recommended.

2.
PNAS Nexus ; 2(7): pgad211, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37416876

RESUMEN

Cyclic anthraquinone derivatives (cAQs), which link two side chains of 1,5-disubstituted anthraquinone as a threading DNA intercalator, have been developed as G-quartet (G4) DNA-specific ligands. Among the cAQs, cAQ-mBen linked through the 1,3-position of benzene had the strongest affinity for G4 recognition and stabilization in vitro and was confirmed to bind to the G4 structure in vivo, selectively inhibiting cancer cell proliferation in correlation with telomerase expression levels and triggering cell apoptosis. RNA-sequencing analysis further indicated that differentially expressed genes regulated by cAQ-mBen were profiled with more potential quadruplex-forming sequences. In the treatment of the tumor-bearing mouse model, cAQ-mBen could effectively reduce tumor tissue and had less adverse effects on healthy tissue. These results suggest that cAQ-mBen can be a potential cancer therapeutic agent as a G4 binder.

3.
Bioorg Med Chem Lett ; 50: 128323, 2021 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-34400300

RESUMEN

Interaction of cyclic naphthalene diimide derivatives (cNDIs), 1-4, with TA-core and c-myc as G-quartet (G4) DNA was studied under dilute or molecular crowding condition. Binding study for TA-core based on an isothermal titration calorimetry showed that 1-4 has 106 M-1 order of binding affinity with the following order: 1 > 4 > 2 > 3 under both conditions. Meting temperature (Tm) of TA-core obtained from the temperature dependence of circular dichroism spectra shows that TA-core was most stabilized by 4, which is in agreement with the result of PCR stop assay and the stabilization effect for 1-3 was correlated with their binding affinity under dilute condition. 3 showed specific growth inhibition of cancer cell line Ca9-22 at <0.03 µM of IC50, with no inhibitory effect against normal bone marrow cells. 3, which has highest value of ΔH/ΔG, shows the highest inhibition ability for Ca9-22, carrying a highest expression level of telomerase mRNA.


Asunto(s)
Antineoplásicos/farmacología , Imidas/farmacología , Naftalenos/farmacología , Antineoplásicos/química , Células de la Médula Ósea/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Dicroismo Circular , Cisplatino/farmacología , G-Cuádruplex , Humanos , Imidas/química , Queratinocitos/efectos de los fármacos , Estructura Molecular , Naftalenos/química , Relación Estructura-Actividad
4.
Drug Metab Dispos ; 36(1): 81-6, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17925384

RESUMEN

Dog albumin contains a specific drug-binding site that binds most of the site II ligands of human albumin. This study was undertaken to elucidate the structural configuration of this binding site using a photoaffinity labeling technique. Dog albumin and albumins of other animal species were photolabeled with [(14)C]ketoprofen. The photolabeled albumins were cleaved with cyanogen bromide (CNBr) and analyzed autoradiographically after electrophoretic separation. A 11.6-kDa CNBr fragment of the photolabeled dog albumin was found to have incorporated most of the radioactivity. Site II ligands of human albumin inhibited photoincorporation of radioactivity to this fragment. The binding constants of human and dog albumins ranged from 10 to 12 x 10(5) M(-1), at least twice as high as those of rat, rabbit, and bovine albumins. Edman degradation was performed to elucidate the amino acid sequence of the photolabeled peptide derived from further digestion of the dog 11.6-kDa CNBr fragment with lysyl endopeptidase. The sequence was XXSESLVXRX, which corresponds to Cys(476)-Arg(485) of dog albumin. Dog albumin contains a binding site that may have a binding microenvironment similar to that of site II on human albumin. Therefore, dog may be a better experimental animal for data extrapolation from animal to human with regard to site II drug-drug interactions.


Asunto(s)
Fragmentos de Péptidos/metabolismo , Albúmina Sérica/metabolismo , Secuencia de Aminoácidos , Animales , Autorradiografía , Sitios de Unión , Radioisótopos de Carbono , Bovinos , Cromatografía Líquida de Alta Presión , Perros , Electroforesis en Gel de Poliacrilamida , Humanos , Ligandos , Datos de Secuencia Molecular , Fragmentos de Péptidos/química , Preparaciones Farmacéuticas/sangre , Preparaciones Farmacéuticas/química , Etiquetas de Fotoafinidad , Unión Proteica , Conejos , Ratas , Albúmina Sérica/química , Especificidad de la Especie
5.
Drug Metab Pharmacokinet ; 19(4): 297-302, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15499198

RESUMEN

The binding properties of the disulfide covalent bond between N-acetyl-L-cysteine (NAC) and human serum albumin (HSA) were investigated. HSA, purified from either healthy subjects or renal failure patients, was incubated with NAC in buffer and analyzed by 4VP-EG-Me column chromatography, which can distinguish between the redox states of the only free thiol of HSA. Although intact HSA was found to consist of mainly three sub-types, marcaptoalbumin (HMA), cysteine-bound nonmercaptoalbumin (HNA(Cys)) and a further oxidized form (HNA(oxy)), the formation of a new type of nonmercaptoalbumin (HNA(NAC)) was confirmed after incubation with NAC. Interestingly, NAC rapidly dissociated Cys from HNA(Cys) and NAC itself bound very slowly to HSA. These findings suggest that the interaction between NAC and HSA proceeds in a 2-step processes. The first-order binding and dissociation rate constants of NAC to healthy HSA (k(on,NAC)) and Cys from healthy HNA(Cys) (k(off,Cys)) were approximately 0.0032 and 1.3 (h(-1)), respectively. On the other hand, HSA from renal failure patients showed decreased HMA and increased HNA(Cys). The k(on,NAC) and k(off,Cys) were 0.0094 and 0.45 (h(-1)), respectively, suggesting that the pathological state may affect the binding properties of HSA and NAC.


Asunto(s)
Acetilcisteína/farmacocinética , Disulfuros/farmacocinética , Polímeros/farmacocinética , Compuestos de Piridinio/farmacocinética , Albúmina Sérica/farmacocinética , Acetilcisteína/análisis , Anciano , Disulfuros/análisis , Femenino , Humanos , Masculino , Unión Proteica/fisiología , Albúmina Sérica/análisis
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