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1.
Proc Natl Acad Sci U S A ; 120(45): e2205463120, 2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-37917793

RESUMEN

Zero-knowledge proof (ZKP) is a fundamental cryptographic primitive that allows a prover to convince a verifier of the validity of a statement without leaking any further information. As an efficient variant of ZKP, noninteractive zero-knowledge proof (NIZKP) adopting the Fiat-Shamir heuristic is essential to a wide spectrum of applications, such as federated learning, blockchain, and social networks. However, the heuristic is typically built upon the random oracle model that makes ideal assumptions about hash functions, which does not hold in reality and thus undermines the security of the protocol. Here, we present a quantum solution to the problem. Instead of resorting to a random oracle model, we implement a quantum randomness service. This service generates random numbers certified by the loophole-free Bell test and delivers them with postquantum cryptography (PQC) authentication. By employing this service, we conceive and implement NIZKP of the three-coloring problem. By bridging together three prominent research themes, quantum nonlocality, PQC, and ZKP, we anticipate this work to inspire more innovative applications that combine quantum information science and the cryptography field.

2.
Phys Rev Lett ; 133(6): 060201, 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39178451

RESUMEN

Bell's theorem states that the quantum mechanical description of physical quantities cannot be fully explained by local realistic theories, laying a solid basis for various quantum information applications. Hardy's paradox is celebrated as the simplest form of Bell's theorem concerning its "All versus Nothing" approach to test local realism. However, due to experimental imperfections, existing tests of Hardy's paradox require additional assumptions of the experimental systems, and these assumptions constitute potential loopholes for faithfully testing local realistic theories. Here, we experimentally demonstrate Hardy's nonlocality through a photonic entanglement source. By achieving a detection efficiency of 82.2%, a quantum state fidelity of 99.10%, and applying high-speed quantum random number generators for the measurement setting switching, the experiment is implemented in a loophole-free manner. During 6 h of running, a strong violation of P_{Hardy}=4.646×10^{-4} up to 5 standard deviations is observed with 4.32×10^{9} trials. A null hypothesis test shows that the results can be explained by local realistic theories with an upper bound probability of 10^{-16348}. These testing results provide affirmative evidence against local realism, and establish an advancing benchmark for quantum information applications based on Hardy's paradox.

3.
J Org Chem ; 89(2): 1353-1360, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38190649

RESUMEN

We have developed a visible light-induced intermolecular [2 + 2]-cycloaddition reaction between alkenes and alkynes using thioxanthone and Cu(OTf)2 as cocatalysts. Various quinolin-2(1H)-ones, featuring diverse substituted groups, were successfully employed in this reaction, resulting in the synthesis of a series of 4,8b-dihydrocyclobuta[c]quinolin-3(2aH)-ones. Our methodology presents a novel synthetic approach for alkene-alkyne [2 + 2]-cycloaddition, delivering cyclobutene derivatives with exceptional regioselectivity.

4.
Chem Soc Rev ; 52(3): 879-920, 2023 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-36637396

RESUMEN

Cancer remains as one of the most significant health problems, with approximately 19 million people diagnosed worldwide each year. Chemotherapy is a routinely used method to treat cancer patients. However, current treatment options lack the appropriate selectivity for cancer cells, are prone to resistance mechanisms, and are plagued with dose-limiting toxicities. As such, researchers have devoted their attention to developing prodrug-based strategies that have the potential to overcome these limitations. This tutorial review highlights recently developed prodrug strategies for cancer therapy. Prodrug examples that provide an integrated diagnostic (fluorescent, photoacoustic, and magnetic resonance imaging) response, which are referred to as theranostics, are also discussed. Owing to the non-invasive nature of light (and X-rays), we have discussed external excitation prodrug strategies as well as examples of activatable photosensitizers that enhance the precision of photodynamic therapy/photothermal therapy. Activatable photosensitizers/photothermal agents can be seen as analogous to prodrugs, with their phototherapeutic properties at a specific wavelength activated in the presence of disease-related biomarkers. We discuss each design strategy and illustrate the importance of targeting biomarkers specific to the tumour microenvironment and biomarkers that are known to be overexpressed within cancer cells. Moreover, we discuss the advantages of each approach and highlight their inherent limitations. We hope in doing so, the reader will appreciate the current challenges and available opportunities in the field and inspire subsequent generations to pursue this crucial area of cancer research.


Asunto(s)
Neoplasias , Fotoquimioterapia , Profármacos , Humanos , Profármacos/farmacología , Profármacos/uso terapéutico , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Fotoquimioterapia/métodos , Neoplasias/diagnóstico por imagen , Neoplasias/tratamiento farmacológico , Microambiente Tumoral
5.
Anal Chem ; 95(13): 5747-5753, 2023 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-36951754

RESUMEN

Drug-induced liver injury (DILI) is a major clinical issue associated with the majority of commercial drugs. During DILI, the peroxynitrite (ONOO-) level is upregulated in the liver. However, traditional methods are unable to timely monitor the dynamic changes of the ONOO- level during DILI in vivo. Therefore, ONOO--activated near-infrared (NIR) fluorescent probes with high sensitivity and selectivity are key to the early diagnosis of DILI in situ. Herein, we report a novel ONOO--responsive NIR fluorescent probe, QCy7-DP, which incorporates a donor-dual-acceptor π-electron cyanine skeleton with diphenyl phosphinate. The ONOO--mediated highly selective hydrolytic cleavage via an addition-elimination pathway of diphenyl phosphinate produced the deprotonated form of QCy7 in physiological conditions with a distinctive extended conjugated π-electron system and ∼200-fold enhancement in NIR fluorescence emission at 710 nm. Moreover, the probe QCy7-DP was successfully used for the imaging of the endogenous and exogenous ONOO- concentration changes in living cells. Importantly, in vivo fluorescence imaging tests demonstrated that the probe can effectively detect the endogenous generation of ONOO- in an acetaminophen (APAP)-induced liver injury mouse model. This study provides insight into the design of highly selective NIR fluorescent probes suitable for spatiotemporal monitoring of ONOO- under different pathological conditions.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas , Colorantes Fluorescentes , Animales , Ratones , Colorantes Fluorescentes/metabolismo , Ácido Peroxinitroso/metabolismo , Compuestos de Bifenilo , Imagen Óptica , Enfermedad Hepática Inducida por Sustancias y Drogas/diagnóstico por imagen
6.
J Am Chem Soc ; 144(1): 174-183, 2022 01 12.
Artículo en Inglés | MEDLINE | ID: mdl-34931825

RESUMEN

Changes in adenosine triphosphate (ATP) and peroxynitrite (ONOO-) concentrations have been correlated in a number of diseases including ischemia-reperfusion injury and drug-induced liver injury. Herein, we report the development of a fluorescent probe ATP-LW, which enables the simultaneous detection of ONOO- and ATP. ONOO- selectively oxidizes the boronate pinacol ester of ATP-LW to afford the fluorescent 4-hydroxy-1,8-naphthalimide product NA-OH (λex = 450 nm, λem = 562 nm or λex = 488 nm, λem = 568 nm). In contrast, the binding of ATP to ATP-LW induces the spirolactam ring opening of rhodamine to afford a highly emissive product (λex = 520 nm, λem = 587 nm). Due to the differences in emission between the ONOO- and ATP products, ATP-LW allows ONOO- levels to be monitored in the green channel (λex = 488 nm, λem = 500-575 nm) and ATP concentrations in the red channel (λex = 514 nm, λem = 575-650 nm). The use of ATP-LW as a combined ONOO- and ATP probe was demonstrated using hepatocytes (HL-7702 cells) in cellular imaging experiments. Treatment of HL-7702 cells with oligomycin A (an inhibitor of ATP synthase) resulted in a reduction of signal intensity in the red channel and an increase in that of the green channel as expected for a reduction in ATP concentrations. Similar fluorescence changes were seen in the presence of SIN-1 (an exogenous ONOO- donor).


Asunto(s)
Ácido Peroxinitroso
7.
Chem Soc Rev ; 50(17): 9391-9429, 2021 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-34232230

RESUMEN

Chemical tools that allow the real-time monitoring of organ function and the visualisation of organ-related processes at the cellular level are of great importance in biological research. The upregulation/downregulation of specific biomarkers is often associated with the development of organ related diseases. Small-molecule fluorescent probes have the potential to create advances in our understanding of these disorders. Viable probes should be endowed with a number of key features that include high biomarker sensitivity, low limit of detection, fast response times and appropriate in vitro and in vivo biocompatibility. In this tutorial review, we discuss the development of probes that allow the targeting of organ related processes in vitro and in vivo. We highlight the design strategy that underlies the preparation of various promising probes, their optical response to key biomarkers, and proof-of-concept biological studies. The inherent drawbacks and limitations are discussed as are the current challenges and opportunities in the field. The hope is that this tutorial review will inspire the further development of small-molecule fluorescent probes that could aid the study of pathogenic conditions that contribute to organ-related diseases.


Asunto(s)
Colorantes Fluorescentes , Biomarcadores , Fluorescencia
8.
Surg Technol Int ; 412022 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-36037398

RESUMEN

BACKGROUND: Physical rehabilitation after total knee arthroplasty (TKA) is important for long-term functional recovery. Recently, sensor-based home rehabilitation (SHR) has gained prominence as a promising method that allows monitoring and guidance that is both structured and accessible, compared to traditional methods of physical rehabilitation. Despite the advent of wearable sensor systems, there is a paucity of evidence regarding SHR in the current literature. Thus, this systematic review aimed to evaluate the effect of wearable SHR on post-TKA outcomes. METHODS: We performed a systematic search of three electronic databases from the beginning of record to March 12, 2021. Primary outcomes were patient-reported outcome measures (PROMs) after rehabilitation, including the Knee Injury and Osteoarthritis Outcome Score (KOOS), Western Ontario and McMaster Universities Arthritis Index (WOMAC) and Knee Society Score (KSS). Secondary outcomes were physical activity levels and functional performance including range of motion (ROM) and Timed Up and Go Test (TUG). RESULTS: A total of 16 studies involving 1321 subjects were included. All wearable sensors in our included studies involved a combination of accelerometers, gyroscopes and magnetometers as functional units. These studies reported favourable outcomes for all three PROMs, although the extent of improvement in specific domains varied among studies. Moreover, physical activity in terms of daily steps and time spent on physical activity increased post-rehabilitation. Similarly, there were improvements in ROM and TUG that reflected a favourable post-operative trajectory during rehabilitation. CONCLUSION: SHR is effective for improving subjective and objective outcomes post-TKA. The role of SHR should be evaluated by a dedicated cost-benefit analysis to facilitate its wider adoption in healthcare systems.

9.
J Am Chem Soc ; 143(3): 1278-1283, 2021 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-33428381

RESUMEN

Deferasirox, ExJade, is an FDA-approved iron chelator used for the treatment of iron overload. In this work, we report several fluorescent deferasirox derivatives that display unique photophysical properties, i.e., aggregation-induced emission (AIE), excited state intramolecular proton transfer, charge transfer, and through-bond and through-space conjugation characteristics in aqueous media. Functionalization of the phenol units on the deferasirox scaffold afforded the fluorescent responsive pro-chelator ExPhos, which enabled the detection of the disease-based biomarker alkaline phosphatase (ALP). The diagnostic potential of these deferasirox derivatives was supported by bacterial biofilm studies.


Asunto(s)
Deferasirox/análogos & derivados , Colorantes Fluorescentes/química , Fosfatasa Alcalina/análisis , Antibacterianos/farmacología , Proteínas Bacterianas/análisis , Biopelículas/efectos de los fármacos , Biomarcadores/análisis , Cefoperazona/farmacología , Deferasirox/farmacología , Deferasirox/efectos de la radiación , Colorantes Fluorescentes/farmacología , Colorantes Fluorescentes/efectos de la radiación , Luz , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/enzimología , Staphylococcus aureus Resistente a Meticilina/fisiología , Pruebas de Sensibilidad Microbiana , Microscopía Confocal , Microscopía Fluorescente , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/enzimología , Pseudomonas aeruginosa/fisiología , Sulbactam/farmacología
10.
J Am Chem Soc ; 142(42): 18005-18013, 2020 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-32955867

RESUMEN

Here, we report a ß-galactosidase (ß-Gal)-responsive photochromic fluorescent probe, NpG, that was designed to prebind to human serum albumin (HSA) to form the probe/protein hybrid, NpG@HSA. The formation of NpG@HSA led to an increase in fluorescence emission (520 nm) corresponding to the binding of the fluorescent naphthalimide unit with HSA. In addition, this enabled visualization of the spiropyran fluorescence emission in aqueous media. Our probe/protein hybrid approach afforded a unique imaging platform with enhanced cell permeability and solubility that was capable of visualizing the cellular uptake of NpG@HSA before its activation by ß-Gal. The ß-Gal-mediated cleavage of the galactose unit within the NpG@HSA hybrid resulted in the formation of NpM@HSA and an increase in red fluorescence emission (620 nm). The resultant merocyanine unit was then able to undergo photoisomerization (merocyanine ↔ spiropyran) to facilitate STORM (i.e., stochastic optical reconstruction microscopy) imaging with minimal phototoxicity and excellent photostability/reversibility. Using STORM, NpG@HSA was able to determine the subcellular distribution of ß-Gal activity between cell lines with nanoscale precision. We believe that this system represents a versatile imaging platform for the design of photochromic fluorescent probes suitable for illuminating the precise location of disease-specific biomarkers in various cellular processes.


Asunto(s)
Colorantes Fluorescentes/química , beta-Galactosidasa/análisis , Biomarcadores/análisis , Biomarcadores/metabolismo , Línea Celular , Colorantes Fluorescentes/síntesis química , Humanos , Microscopía Confocal , Estructura Molecular , Imagen Óptica , Procesos Fotoquímicos , Albúmina Sérica Humana/química , beta-Galactosidasa/metabolismo
11.
Chemistry ; 26(63): 14445-14452, 2020 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-32864796

RESUMEN

Two red-emitting dicyanomethylene-4H-pyran (DM) based fluorescent probes were designed and used for peroxynitrite (ONOO- ) detection. Nevertheless, the aggregation-caused quenching effect diminished the fluorescence and restricted their further applications. To overcome this problem, tetraphenylethylene (TPE) based glycoclusters were used to self-assemble with these DM probes to obtain supramolecular water-soluble glyco-dots. This self-assembly strategy enhanced the fluorescence intensity, leading to an enhanced selectivity and activity of the resulting glyco-dot comparing to DM probes alone in PBS buffer. The glyco-dots also exhibited better results during fluorescence sensing of intracellular ONOO- than the probes alone, thereby offering scope for the development of other similar supramolecular glyco-systems for chemical biological studies.


Asunto(s)
Colorantes Fluorescentes , Imagen Óptica , Ácido Peroxinitroso , Piranos , Estilbenos , Colorantes Fluorescentes/química , Colorantes Fluorescentes/normas , Glicoconjugados/química , Imagen Óptica/métodos , Ácido Peroxinitroso/análisis , Piranos/química , Estilbenos/química
12.
Arch Insect Biochem Physiol ; 105(1): e21720, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32557681

RESUMEN

The large-conductance calcium-activated potassium channel (BKCa ) plays an important role in the regulation of insect neural circuits and locomotion, and thus is a potential target of insecticides. In this study, iberiotoxin, an inhibitor of BKCa , was found to prolong the anesthetic time of ethyl acetate on Plutella xylostella larvae. Therefore, the coding sequence of slowpoke gene coding the alpha subunit of BKCa was cloned to investigate the function of this channel in P. xylostella, and the gene expression profile in the developmental stages and tissues was also characterized. The total length of pxslo DNA was more than 19.9 kb, which harbored four alternative splicing sites (ASP-A, ASP-C, ASP-E, and ASP-G), and the coding sequence of pxslo with the highest frequency of splicing (GenBank ID: MN938456) was 3,405 base pair. The characterized PxSlo protein contained conserved domains previously identified in other insects. Quantitative reverse transcription-polymerase chain reaction analysis showed that pxslo was expressed in all the developmental stages of P. xylostella, with the highest level in adults. In the larval stage, pxslo was mainly expressed in the head and epidermis, while a limited protein was expressed in the midgut. In the adult stage, pxslo was highly expressed in the head, followed by in the ovarian tubule, and was not expressed in the testis or wings. These results suggest that BKCa plays an important physiological role in P. xylostella and provides useful information for the functional study and screening of BKCa inhibitors.


Asunto(s)
Proteínas de Insectos/genética , Canales de Potasio de Gran Conductancia Activados por el Calcio/genética , Mariposas Nocturnas/genética , Transcriptoma , Secuencia de Aminoácidos , Animales , Proteínas de Insectos/química , Proteínas de Insectos/metabolismo , Canales de Potasio de Gran Conductancia Activados por el Calcio/química , Canales de Potasio de Gran Conductancia Activados por el Calcio/metabolismo , Larva/genética , Larva/crecimiento & desarrollo , Mariposas Nocturnas/crecimiento & desarrollo , Mariposas Nocturnas/metabolismo , Óvulo/crecimiento & desarrollo , Pupa/genética , Pupa/crecimiento & desarrollo , Alineación de Secuencia
13.
BMC Biotechnol ; 19(1): 30, 2019 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-31118001

RESUMEN

BACKGROUND: The potassium dichromate oxidation method used in determination of alcohols in fermentation has two major disadvantages. This method cannot be used to determine alcohols in raw fermentation broth samples, which often contain various reducing sugars. The method is not environment friendly due to the carcinogenicity of Cr (VI) used. RESULTS: A new method for determination of reducing sugars and total alcohols in raw fermentation broths was developed. The fermentation broth was pretreated to remove proteins, polysaccharides, glycerol and organic acids. The colorimetric change from both total alcohols and reducing sugars by potassium permanganate oxidation was measured. The portion of colorimetric change from oxidation of reducing sugars was determined by DNS test and subtracted. The remaining portion of colorimetric change was then used to calculate the total alcohol concentration in the sample. CONCLUSIONS: Using this method, total alcohol concentration can be easily and accurately determined in both distilled samples and raw fermentation broth samples. It is fast and environmental friendly.


Asunto(s)
Etanol/análisis , Fermentación , Ensayos Analíticos de Alto Rendimiento/métodos , Permanganato de Potasio/metabolismo , Azúcares/análisis , Colorimetría/métodos , Medios de Cultivo Condicionados/química , Etanol/metabolismo , Oxidación-Reducción , Permanganato de Potasio/química , Reproducibilidad de los Resultados , Azúcares/metabolismo
14.
Chem Soc Rev ; 47(23): 8842-8880, 2018 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-30361725

RESUMEN

In this review we will explore recent advances in the design and application of excited-state intramolecular proton-transfer (ESIPT) based fluorescent probes. Fluorescence based sensors and imaging agents (probes) are important in biology, physiology, pharmacology, and environmental science for the selective detection of biologically and/or environmentally important species. The development of ESIPT-based fluorescence probes is particularly attractive due to their unique properties, which include a large Stokes shift, environmental sensitivity and potential for ratiometric sensing.


Asunto(s)
Colorantes Fluorescentes/química , Imagen Óptica , Protones , Colorantes Fluorescentes/síntesis química , Humanos , Estructura Molecular , Espectrometría de Fluorescencia
15.
Int J Mol Sci ; 20(13)2019 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-31284427

RESUMEN

This study investigated the effect of a novel progestin and its combination with metformin on the growth of endometrial cancer (EC) cells. Inhibitory effects of four progestins, including nomegestrol acetate (NOMAC), medroxyprogesterone acetate, levonorgestrel, and cyproterone acetate, were evaluated in RL95-2, HEC-1A, and KLE cells using cell counting kit-8 assay. Flow cytometry was performed to detect cell cycle and apoptosis. The activity of Akt (protein kinase B), mTOR (mammalian target of rapamycin) and its downstream substrates 4EBP1 (4E-binding protein 1) and eIF4G (Eukaryotic translation initiation factor 4G) were assayed by Western blotting. Nude mice were used to assess antitumor effects in vivo. NOMAC inhibited the growth of RL95-2 and HEC-1A cells, accompanied by arresting the cell cycle at G0/G1 phase, inducing apoptosis, and markedly down-regulating the level of phosphorylated mTOR/4EBP1/eIF4G in both cell lines (p < 0.05). Metformin significantly increased the inhibitory effect of and apoptosis induced by NOMAC and strengthened the depressive effect of NOMAC on activity of mTOR and its downstream substrates, compared to their treatment alone (p < 0.05). In xenograft tumor tissues, metformin (100 mg/kg) enhanced the suppressive effect of NOMAC (100 mg/kg) on mTOR signaling and increased the average concentration of NOMAC by nearly 1.6 times compared to NOMAC treatment alone. Taken together, NOMAC suppressing the growth of EC cells likely correlates to down-regulating the activity of the mTOR pathway and metformin could strengthen this effect. Our findings open a new window for the selection of progestins in hormone therapy of EC.


Asunto(s)
Regulación hacia Abajo/efectos de los fármacos , Neoplasias Endometriales/enzimología , Neoplasias Endometriales/patología , Megestrol/farmacología , Metformina/farmacología , Norpregnadienos/farmacología , Serina-Treonina Quinasas TOR/metabolismo , Proteínas Adaptadoras Transductoras de Señales , Animales , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Proteínas de Ciclo Celular , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Receptor alfa de Estrógeno/metabolismo , Factor 4G Eucariótico de Iniciación/metabolismo , Femenino , Humanos , Megestrol/química , Metformina/química , Ratones Desnudos , Norpregnadienos/química , Fosforilación/efectos de los fármacos , Receptores de Progesterona/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
16.
Beilstein J Org Chem ; 15: 2380-2389, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31666872

RESUMEN

The development of photochromic fluorescence sensors with dynamic and multiple-signaling is beneficial to the improvement of biosensing/imaging precision. However, elaborate designs with complicated molecular structures are always required to integrate these functions into one molecule. By taking advantages of both redox-active/high loading features of two-dimensional (2D) manganese dioxide (MnO2) and dynamic fluorescence photoswitching of photochromic sensors, we here design a hybrid photochromic MnO2 glycosheet (Glyco-DTE@MnO 2 ) to achieve the photoswitchable imaging of intracellular glutathione (GSH). The photochromic glycosheet manifests significantly turn-on fluorescence and dynamic ON/OFF fluorescence signals in response to GSH, which makes it favorable for intracellular GSH double-check in targeted human hepatoma cell line (HepG2) through the recognition between ß-D-galactoside and asialoglycoprotein receptor (ASGPr) on cell membranes. The dynamic fluorescence signals and excellent selectivity for detection and imaging of GSH ensure the precise determination of cell states, promoting its potential applications in future disease diagnosis and therapy.

17.
J Am Chem Soc ; 140(28): 8671-8674, 2018 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-29940117

RESUMEN

Despite the rapid development of imaging techniques, precise probe localization and modulation in living cells is still a challenging task. Here we show that the simple hybridization between a photochromic fluorescent glycoprobe and human serum albumin (HSA) enables a unique fluorescence "double-check" mechanism for precisely localizing and manipulating probe molecules in living cells. Docking of a carbohydrate-modified naphthalimide (Naph)-spiropyran (SP) dyad to a hydrophobic pocket of HSA produces the glycoprobe-protein hybrid, causing the protein conformation to fold as determined by small-angle X-ray scattering. We show that the Naph and merocyanine (the photoisomer of SP) fluorescence of the resulting hybrid can be reversibly switched by light in buffer solution and in target cells overexpressing the carbohydrate receptor.


Asunto(s)
Receptor de Asialoglicoproteína/análisis , Benzopiranos/química , Colorantes Fluorescentes/química , Indoles/química , Nitrocompuestos/química , Albúmina Sérica Humana/química , Sitios de Unión , Fluorescencia , Células Hep G2 , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Luz , Simulación del Acoplamiento Molecular , Naftalimidas/química , Imagen Óptica/métodos , Conformación Proteica
18.
J Urol ; 199(2): 568-575, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28866465

RESUMEN

PURPOSE: The sonourethrogram is a useful alternative to the traditional retrograde urethrogram to evaluate anterior urethral strictures. With the development of 3-dimensional reconstructive techniques 3-dimensional urethral imaging can provide more accurate and useful information to enable the surgeon to make the best surgical decisions. We evaluated the accuracy and efficacy of a 3-dimensional reconstructed digital model of the urethra based on the sonourethrogram to assess anterior urethral disease. MATERIALS AND METHODS: A total of 50 patients with an anterior urethral stricture and 10 healthy volunteers were enrolled in this study from April 2014 to January 2017. All patients and volunteers underwent sonourethrogram and retrograde urethrogram. Three-dimensional urethral models were reconstructed based on the sonourethrogram. Stricture length and location on retrograde urethrogram or sonourethrogram based images were compared with those found at operation. RESULTS: The 3-dimensional digital model revealed the entire anterior urethra, including the navicular fossa, and the penile and bulbar parts. The semitransparent model clearly demonstrated the structure of the corpus spongiosum and inside the urethral lumen. Further information on spongiofibrosis could also be seen in the 3-dimensional digital model. There was no significant difference in stricture length or location in the 3-dimensional model compared with retrograde urethrogram imaging and actual surgical findings. However, the latest technique could only reconstruct the short segment of the anterior urethra due to the probe width limitation. CONCLUSIONS: The 3-dimensional computerized model based on the sonourethrogram is a novel and effective technique of evaluating anterior urethral strictures.


Asunto(s)
Ultrasonografía/métodos , Estrechez Uretral/diagnóstico por imagen , Urografía/métodos , Adulto , Anciano , Simulación por Computador , Voluntarios Sanos , Humanos , Imagenología Tridimensional , Masculino , Persona de Mediana Edad , Adulto Joven
19.
Bioorg Med Chem ; 26(14): 4254-4263, 2018 08 07.
Artículo en Inglés | MEDLINE | ID: mdl-30054192

RESUMEN

With the purpose of identifying novel selective κ opioid receptor (KOR) antagonists as potential antidepressants from nepenthone analogues, starting from N-nor-N-cyclopropylmethyl-nepenthone (SLL-020ACP), a highly selective and potent KOR agonist, a series of 7ß-methyl-nepenthone analogues was conceived, synthesized and assayed on opioid receptors based on the concept of hybridization. According to the pharmacological results, the functional reversal observed in orvinol analogues by introduction of 7ß-methyl substituent could not be reproduced in nepenthone analogues. Alternatively, introduction of 7ß-methyl substituent was associated with substantial loss of both subtype selectivity and potency but not efficacy for nepenthone analogues, which was not found in 7ß-methyl orvinol analogues. Surprisingly, SLL-603, a 7ß-methyl analogue of SLL-020ACP, was identified to be a KOR full agonist. The possible molecular mechanism for the heterogeneity in activity cliff was also investigated. In conclusion, 7ß-methyl substituent was a structural locus associated with activity cliff and demonstrated as a pharmacological heterogeneity between nepenthone and orvinol analogues that warrants further investigations.


Asunto(s)
Morfinanos/farmacología , Receptores Opioides kappa/agonistas , Animales , Células CHO , Células Cultivadas , Cricetulus , Relación Dosis-Respuesta a Droga , Modelos Moleculares , Estructura Molecular , Morfinanos/síntesis química , Morfinanos/química , Relación Estructura-Actividad
20.
Arch Insect Biochem Physiol ; 98(4): e21466, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29691888

RESUMEN

The ß-adrenergic-like octopamine receptor (OA2B2) belongs to the class of G-protein coupled receptors. It regulates important physiological functions in insects, thus is potentially a good target for insecticides. In this study, the putative open reading frame sequence of the Pxoa2b2 gene in Plutella xylostella was cloned. Orthologous sequence alignment, phylogenetic tree analysis, and protein sequence analysis all showed that the cloned receptor belongs to the OA2B2 protein family. PxOA2B2 was transiently expressed in HEK-293 cells. It was found that PxOA2B2 could be activated by both octopamine and tyramine, resulting in increased intracellular cyclic AMP (cAMP) levels, whereas dopamine and serotonin were not effective in eliciting cAMP production. Further studies with series of PxOA2B2 agonists and antagonists showed that all four tested agonists (e.g., naphazoline, clonidine, 2-phenylethylamine, and amitraz) could activate the PxOA2B2 receptor, and two of tested antagonists (e.g., phentolamine and mianserin) had significant antagonistic effects. However, antagonist of yohimbine had no effects. Quantitative real-time polymerase chain reaction analysis showed that Pxoa2b2 gene was expressed in all developmental stages of P. xylostella and that the highest expression occurred in male adults. Further analysis with fourth-instar P. xylostella larvae showed that the Pxoa2b2 gene was mainly expressed in Malpighian tubule, epidermal, and head tissues. This study provides both a pharmacological characterization and the gene expression patterns of the OA2B2 in P. xylostella, facilitating further research for insecticides using PxOA2B2 as a target.


Asunto(s)
Proteínas de Insectos/genética , Mariposas Nocturnas/genética , Receptores de Amina Biogénica/genética , Secuencia de Aminoácidos , Animales , Femenino , Perfilación de la Expresión Génica , Células HEK293 , Humanos , Proteínas de Insectos/química , Proteínas de Insectos/metabolismo , Larva/genética , Larva/crecimiento & desarrollo , Larva/metabolismo , Masculino , Mariposas Nocturnas/crecimiento & desarrollo , Mariposas Nocturnas/metabolismo , Óvulo/crecimiento & desarrollo , Óvulo/metabolismo , Filogenia , Pupa/genética , Pupa/crecimiento & desarrollo , Pupa/metabolismo , Receptores de Amina Biogénica/química , Receptores de Amina Biogénica/metabolismo , Alineación de Secuencia
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