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1.
Opt Express ; 32(12): 21977-21987, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38859538

RESUMEN

Quantum teleportation is a building block in quantum computation and quantum communication. The continuous-variable polarization squeezed state is a key resource in quantum networks, offering advantages for long-distance distribution and direct interfacing of quantum nodes. Although polarization squeezed state has been generated and distributed between remote users, it is a long-standing goal to implement controlled quantum teleportation of the polarization squeezed state with multiple remote users. Here, we propose a feasible scheme to teleport a polarization squeezed state among multiple remote users under control. The polarization state is transferred between different remote quantum networks, and the controlled quantum teleportation of the polarization state can be implemented in one quantum network involving multiple remote users. The results show that such a controlled quantum teleportation can be realized with 36 users through about 6-km free-space or fiber quantum channels, where the fidelity of 0.352 is achieved beyond the classical limit of 0.349 with an input squeezing variance of 0.25. This scheme provides a direct reference for the experimental implementation of remote and controlled quantum teleportation of polarization states, thus enabling more teleportation-based quantum network protocols.

2.
Opt Express ; 32(10): 18237-18246, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38858985

RESUMEN

Quantum random numbers play a crucial role in diverse applications, including cryptography, simulation, and artificial intelligence. In contrast to predictable algorithm-based pseudo-random numbers, quantum physics provides new avenues for generating theoretically true random numbers by exploiting the inherent uncertainty contained in quantum phenomena. Here, we propose and demonstrate a quantum random number generator (QRNG) using a prepared broadband squeezed state of light, where the randomness of the generated numbers entirely originates from the quantum noise introduced by squeezing operation rather than vacuum noise. The relationship between entropy rate and squeezing level is analyzed. Furthermore, we employ a source-independent quantum random number protocol to enhance the security of the random number generator.

3.
Phys Rev Lett ; 132(14): 140802, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38640392

RESUMEN

Quantum dense coding (QDC) means to transmit two classical bits by only transferring one quantum bit, which has enabled high-capacity information transmission and strengthened system security. Continuous-variable QDC offers a promising solution to increase communication rates while achieving seamless integration with classical communication systems. Here, we propose and experimentally demonstrate a high-speed quantum radio-frequency-over-light (RFOL) communication scheme based on QDC with an entangled state, and achieve a practical rate of 20 Mbps through digital modulation and RFOL communication. This scheme bridges the gap between quantum technology and real-world communication systems, which bring QDC closer to practical applications and offer prospects for further enhancement of metropolitan communication networks.

4.
Opt Express ; 31(5): 8257-8266, 2023 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-36859941

RESUMEN

Multipartite Einstein-Podolsky-Rosen (EPR) steering is a key resource in a quantum network. Although EPR steering between spatially separated regions of ultracold atomic systems has been observed, deterministic manipulation of steering between distant quantum network nodes is required for a secure quantum communication network. Here, we propose a feasible scheme to deterministically generate, store, and manipulate one-way EPR steering between distant atomic cells by a cavity-enhanced quantum memory approach. While optical cavities effectively suppress the unavoidable noises in electromagnetically induced transparency, three atomic cells are in a strong Greenberger-Horne-Zeilinger state by faithfully storing three spatially separated entangled optical modes. In this way, the strong quantum correlation of atomic cells guarantees one-to-two node EPR steering is achieved, and can perserve the stored EPR steering in these quantum nodes. Furthermore, the steerability can be actively manipulated by the temperature of the atomic cell. This scheme provides the direct reference for experimental implementation for one-way multipartite steerable states, which enables an asymmetric quantum network protocol.

5.
J Sleep Res ; 32(2): e13736, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36163423

RESUMEN

The hypocretin neurons in the lateral hypothalamus are connected not only to brain alertness systems but also to brainstem nuclei that regulate blood pressure and heart rate. The premise is that regulation of blood pressure and heart rate is altered and affected by methylphenidate, a stimulant drug in children with narcolepsy with cataplexy. The changes in 24-hr ambulatory systolic and diastolic blood pressure and heart rate were compared among pre-treated narcolepsy with cataplexy patients (40 males, 10 females), with mean age 10.4 ± 3.5 years (M ±â€…SD, range 5-17 years) with values from 100 archival age-sex-body mass index matched controls. Patients had a lower diurnal systolic blood pressure (-6.5 mmHg; p = 0.000) but higher heart rate (+11.0 bpm; p = 0.000), particularly evident in the waketime, while diastolic blood pressure was comparable. With methylphenidate (18 mg sustained release at 08:00 hours), patients with narcolepsy with cataplexy had higher systolic blood pressure (+4.6 mmHg, p = 0.015), diastolic blood pressure (+3.3 mmHg, p = 0.005) and heart rate (+7.1 bpm, p = 0.028) during wake time, but nighttime cardiovascular values were unchanged from pre-treated values; amplitude variation in cardiovascular values was unchanged over 24 hr. In conclusion, children with narcolepsy with cataplexy had downregulation blood pressure profile but a higher heart rate, and lesser non-dipping profiles. Daytime methylphenidate treatment increases only waketime blood pressure and further elevated heart rate values.


Asunto(s)
Cataplejía , Metilfenidato , Narcolepsia , Neuropéptidos , Masculino , Femenino , Humanos , Niño , Preescolar , Adolescente , Cataplejía/tratamiento farmacológico , Frecuencia Cardíaca/fisiología , Presión Sanguínea/fisiología , Narcolepsia/tratamiento farmacológico , Metilfenidato/farmacología , Metilfenidato/uso terapéutico
6.
Opt Express ; 30(4): 6388-6396, 2022 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-35209578

RESUMEN

Quantum network plays a vitally important role in the practical application of quantum information, which requires the deterministic entanglement distribution among multiple remote users. Here, we propose a feasible scheme to deterministically distribute quadripartite entanglement by continuous-variable (CV) polarization states. The quantum server prepares the quadripartite CV polarization entanglement and distributes them to four remote users via optical fiber. In this way, the measurement of CV polarization entanglement is local oscillation free, which makes the long distance entanglement distribution in commercial optical fiber communication networks possible. Furthermore, both the Greenberger-Horne-Zeilinger-like (GHZ-like) and cluster-like polarization entangled states can be distributed among four users by controlling the beam splitter network in quantum server, which are confirmed by the extended criteria for polarization entanglement of multipartite optical modes. The protocol provides the direct reference for experimental implementation and can be directly extended to quantum network with more users, which is essential for a metropolitan quantum network.

7.
Opt Express ; 30(26): 47826-47835, 2022 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-36558701

RESUMEN

High-precision cavity locking is crucial for squeezing optical fields. Here, a bootstrapped low-noise photodetector is utilized in the generation process of the squeezed state of light. This process is based on a combination of a modified trans-impedance amplifier (TIA) circuit and a two-stage bootstrap amplifier circuit. This not only achieves high-precision and long-term stable locking of the optical cavity, but it also improves the degree to which the light field is squeezed. The experiment results show that the detector has a high signal-to-noise ratio (SNR) of 26.7 dB at the analysis frequency of 3 MHz when measuring the shot noise with an injection optical power of 800 µW, and the equivalent optical power noise level is lower than 2.4 pW/Hz in the frequency range of 1-30 MHz. Moreover, the squeezing degree of the quadrature amplitude squeezed state light field can be improved by more than 34.9% when the detector is used for optical cavity locking. The photodetector is useful in continuous variable (CV) quantum information research.

8.
Dig Dis Sci ; 67(12): 5529-5539, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35314916

RESUMEN

BACKGROUND: The NF-κB signaling cascade regulates immune response and is often dysregulated in tumor development. UBE2W is a novel type I ubiquitin-conjugating enzyme (E2) whose biological function is still unclear. AIMS: This study was designed to investigate whether UBE2W regulates NF-κB signaling pathway and is involved in the progression of experimental colitis. METHODS: At the cellular level, the effect of UBE2W on NF-κB transcriptional activity was measured using a dual-luciferase reporter assay. The influence of UBE2W on NF-κB pathway activation and the entry of p65 into the nucleus were determined by Western blot and immunofluorescence analyses, respectively. Moreover, the colitis model was established by administering 2.5% dextran sulfate sodium (DSS)/water to UBE2W overexpression, UBE2W-knockdown and control mice. Body weight, stool consistency, colon length and clinical severity were examined. Expression of pro-inflammatory cytokines and phosphorylation of p65 and IκB in the colon tissue were measured by qRT-PCR and Western blot, respectively. RESULTS: UBE2W inhibited TNFα-induced NF-κB transcription activity, attenuated IκB and p65 phosphorylation, downregulated TNFα and IL-8 expression and blocked the entry of p65 into the nucleus. In the DSS-induced colitis model, UBE2W-knockdown mice had increased weight loss, more serious diarrhea and mucosal injures compared with the control mice. Moreover, phosphorylation of IκB and p65 and the expression of pro-inflammatory mediators such as TNFα, IL-6 were significantly increased in UBE2W knockdown mice. However, these changes were completely reversed in UBE2W overexpression mice. CONCLUSIONS: The overexpression of UBE2W ameliorates the severity of DSS-induced colitis, which may be mediated by inhibiting the expression of pro-inflammatory mediators and activation of the NF-κB signaling pathway. These findings provide evidence that UBE2W might have potential therapeutic implications in IBD.


Asunto(s)
Colitis , FN-kappa B , Ratones , Animales , FN-kappa B/metabolismo , Factor de Necrosis Tumoral alfa/farmacología , Sulfato de Dextran/toxicidad , Modelos Animales de Enfermedad , Colitis/patología , Transducción de Señal , Mediadores de Inflamación/metabolismo , Ratones Endogámicos C57BL , Enzimas Ubiquitina-Conjugadoras/genética , Enzimas Ubiquitina-Conjugadoras/metabolismo
9.
Phys Rev Lett ; 124(17): 173602, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32412253

RESUMEN

High precision interferometers are the building blocks of precision metrology and the ultimate interferometric sensitivity is limited by the quantum noise. Here, we propose and experimentally demonstrate a compact quantum interferometer involving two optical parametric amplifiers and the squeezed states generated within the interferometer are directly used for the phase-sensing quantum state. By both squeezing shot noise and amplifying phase-sensing intensity the sensitivity improvement of 4.86±0.24 dB beyond the standard quantum limit is deterministically realized and a minimum detectable phase smaller than that of all present interferometers under the same phase-sensing intensity is achieved. This interferometric system has significantly potential applications in a variety of measurements for tiny variances of physical quantities.

10.
Dig Dis Sci ; 65(12): 3514-3520, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32078087

RESUMEN

BACKGROUND: The specific and accurate pathogenesis of diarrhea-type irritable bowel syndrome is still unclear. AIMS: We explored the mechanism of heat shock protein 27 (HSP27) in diarrhea-type irritable bowel syndrome to identify the key targets for the disease. METHODS: The human colonic epithelial cell lines Caco-2 and NCM460 were pretreated with KRIBB3 (a phosphorylation inhibitor of HSP27) and then stimulated with lipopolysaccharide for different times. The apoptosis ratios of Caco-2 and NCM460 cells were examined with Annexin V/PI assays. Cell growth was determined using the cell counting kit-8 assay, and the expression levels of IL-1ß and IL-6 in the cell supernatant were analyzed by ELISA. In addition, the expression levels of HSP27 and the nuclear factor-κB (NF-κB) signaling pathway were examined by Western blot assay. RESULTS: Stimulation with lipopolysaccharide promoted the expression of HSP27 in colonic epithelial cells. HSP27 was phosphorylated at serine 78 and 82 after exposure to LPS. Apoptosis, growth inhibition, and inflammatory factor expression of lipopolysaccharide-induced colonic epithelial cells were greatly exacerbated by KRIBB3 treatment. In addition, KRIBB3 inhibited the phosphorylation of IκB-α and the activation of NF-κB. Gene silencing by small interfering RNA indicated that phosphorylation of HSP27 may regulate the NF-κB pathway. CONCLUSIONS: HSP27 plays an important role in the inflammatory response of intestinal human colonic epithelial cells. HSP27 may protect intestinal epithelial cells against damage by regulating the NF-κB pathway.


Asunto(s)
Proteínas de Choque Térmico HSP27/metabolismo , Mucosa Intestinal/metabolismo , Síndrome del Colon Irritable/metabolismo , FN-kappa B/metabolismo , Anisoles/farmacología , Antimetabolitos/farmacología , Células Cultivadas , Diarrea , Silenciador del Gen , Humanos , Inflamación/metabolismo , Síndrome del Colon Irritable/fisiopatología , Isoxazoles/farmacología , Fosforilación/efectos de los fármacos , ARN Interferente Pequeño/metabolismo , Transducción de Señal
11.
Opt Express ; 27(3): 3247-3254, 2019 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-30732348

RESUMEN

Continuous-wave, single-frequency, solid-state lasers with long-term frequency stability and low-intensity noise are an essential resource to generate squeezed and entangled states of light. In order to obtain the stable, nonclassical states of light, the frequency of the laser has to be stabilized with a stable reference. Due to the zero expansion property at a certain temperature, an ultra-low expansion (ULE) Fabry-Perot (F-P) cavity with a high finesse can be used as one of the best candidates of the frequency reference. We perform a detailed analysis of an extraordinarily high-frequency stability and ultra-low-intensity noise laser based on an improved cascade Pound-Drever-Hall frequency stabilization to a ULE F-P cavity. The frequency drift of the laser is suppressed to 7.72 MHz in 4 hours, and the noise level of the laser is simultaneously reduced to the quantum noise limit in the frequency below 300 kHz, which provides the possibility for the direct generation of a stable, high-level squeezed state in a lower-frequency region.

12.
Phys Rev Lett ; 121(15): 150502, 2018 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-30362796

RESUMEN

Secret sharing is a conventional technique for realizing secure communications in information networks, where a dealer distributes to n players a secret, which can only be decoded through the cooperation of k (n/2

13.
BMC Genomics ; 18(1): 358, 2017 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-28482814

RESUMEN

BACKGROUND: Transient starch provides carbon and energy for plant growth, and its synthesis is regulated by the joint action of a series of enzymes. Starch synthesis IV (SSIV) is one of the important starch synthase isoforms, but its impact on wheat starch synthesis has not yet been reported due to the lack of mutant lines. RESULTS: Using the TILLING approach, we identified 54 mutations in the wheat gene TaSSIVb-D, with a mutation density of 1/165 Kb. Among these, three missense mutations and one nonsense mutation were predicted to have severe impacts on protein function. In the mutants, TaSSIVb-D was significantly down-regulated without compensatory increases in the homoeologous genes TaSSIVb-A and TaSSIVb-B. Altered expression of TaSSIVb-D affected granule number per chloroplast; compared with wild type, the number of chloroplasts containing 0-2 granules was significantly increased, while the number containing 3-4 granules was decreased. Photosynthesis was affected accordingly; the maximum quantum yield and yield of PSII were significantly reduced in the nonsense mutant at the heading stage. CONCLUSIONS: These results indicate that TaSSIVb-D plays an important role in the formation of transient starch granules in wheat, which in turn impact the efficiency of photosynthesis. The mutagenized population created in this study allows the efficient identification of novel alleles of target genes and could be used as a resource for wheat functional genomics.


Asunto(s)
Alelos , Cloroplastos/metabolismo , Mutación , Proteínas de Plantas/genética , Almidón/biosíntesis , Triticum/genética , Triticum/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Fotosíntesis/genética , Complejo de Proteína del Fotosistema II/metabolismo , Proteínas de Plantas/metabolismo , Triticum/citología , Triticum/crecimiento & desarrollo
14.
Int J Audiol ; 56(1): 33-37, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27686369

RESUMEN

OBJECTIVE: Persistent postural-perceptual dizziness (PPPD) is a common cause of chronic dizziness, but only a few studies have reported its clinical characteristics, and no related research has been performed in China. Therefore, the purpose of this study was to analyze the characteristics of PPPD for the first time in China. DESIGN: Data was collected from all patients during standard clinical practice, and further to evaluate the characteristics of PPPD comparing with the control group. STUDY SAMPLE: A total of 43 patients diagnosed with PPPD were selected as the study group for analysis. RESULTS: Women were significantly more represented in the study group than men, and in the majority of cases the age of onset was in middle-age, and sleep quality was clearly decreased compared with controls, with more statistically significantly higher levels of anxiety. Personality analysis identified that neuroticism was significantly higher than in controls. CONCLUSIONS: In this sample we showed that PPPD was more represented in female patients, the age of onset was 40-60 years old, the majority of patients had sleep disorders, anxiety was the main mood disorder to be identified, and personality analysis found that neurotic personality may be the risk factor for developing PPPD. Further large scale studies are suggested in China.


Asunto(s)
Mareo/psicología , Percepción , Equilibrio Postural , Adulto , Afecto , Anciano , Ansiedad/epidemiología , Ansiedad/psicología , Estudios de Casos y Controles , China/epidemiología , Mareo/diagnóstico , Mareo/epidemiología , Mareo/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neuroticismo , Inventario de Personalidad , Factores de Riesgo , Sueño , Trastornos del Sueño-Vigilia/epidemiología , Trastornos del Sueño-Vigilia/fisiopatología , Trastornos del Sueño-Vigilia/psicología , Encuestas y Cuestionarios , Adulto Joven
15.
BMC Neurol ; 15: 168, 2015 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-26382591

RESUMEN

BACKGROUND: Medication overuse headache (MOH) is the third most prevalent headache type after migraine and tension-type headache. A large number of studies on the long-term prognosis have shown that MOH has a high relapse rate after treatment. Although MOH relapse-related risk factors have been reported, no related research has been performed in China. Therefore, the purpose of this study was to analyze and evaluate the risk factors for MOH relapse in China. METHODS: Eighty-six out-patients of Shandong Provincial Hospital who were initially diagnosed with MOH, and who had successful withdrawal treatment within 2 months, were chosen from March 2012 to July 2013. All subjects were followed up by the investigators of this study. Of the 86 subjects, 27 who had relapsed were compared with 59 who had not relapsed (i.e. the controls). Based on a standardized questionnaire, a database was created (with Microsoft Excel 2010). The data, which included 38 indexes, were analyzed by univariate analysis with chi-square test, Fisher's exact test, t-test, or paired rank test. The statistically correlated (P<0.05) variables were chosen as the independent variables, thereby enabling the calculation of the non-conditional multivariate stepwise logistic regression. RESULTS: The independent risk factors for medication-overuse headache relapse were determined as headache frequency before drug withdrawal, duration of primary headache, and headache frequency after drug withdrawal. CONCLUSION: Headache frequency before drug withdrawal, duration of primary headache, and headache frequency after drug withdrawal may be the independent risk factors for MOH relapse in China.


Asunto(s)
Cefaleas Secundarias/etiología , Adolescente , Adulto , Anciano , Analgésicos/uso terapéutico , Antiinflamatorios no Esteroideos/uso terapéutico , Benzodiazepinas/uso terapéutico , Medicamentos Herbarios Chinos/uso terapéutico , Femenino , Estudios de Seguimiento , Cefaleas Secundarias/clasificación , Cefaleas Secundarias/prevención & control , Humanos , Masculino , Persona de Mediana Edad , Trastornos Migrañosos/tratamiento farmacológico , Pronóstico , Recurrencia , Factores de Riesgo , Cefalea de Tipo Tensional/tratamiento farmacológico , Factores de Tiempo , Adulto Joven
16.
J Stroke Cerebrovasc Dis ; 24(9): e265-9, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26163886

RESUMEN

Acute cerebral infarction (ACI) caused by cervical arterial dissection (CAD) is a rare clinical disease. Therapeutic approaches include anticoagulant therapy, antiplatelet aggregation, and thrombolytic therapy. Currently, anticoagulant therapy or antiplatelet aggregation is the primary choice, whereas the thrombolytic therapy is still controversial. In this article, we report a patient with ACI caused by right CAD, which led to a compensatory increase in blood supply to the right middle cerebral artery through the anterior communicating artery. After treatment with intravenous thrombolysis, the clinical symptoms of the patient improved, and the National Institutes of Health Stroke Scale (NIHSS) score declined to 2 points from the initial 14 points. In addition, cranial computed tomography scans showed that there were no signs of intracranial or extracranial hemorrhage, but that the vessel occlusion was still uncured. After 17 days of antiplatelet aggregation treatment, a cranial magnetic resonance angiography scan showed complete recanalization of the right internal carotid artery. Furthermore, the NIHSS score was reduced to 1 point when the patient discharged, and for 3 months of follow-up.


Asunto(s)
Disección Aórtica/complicaciones , Infarto Cerebral/etiología , Infarto Cerebral/terapia , Terapia Trombolítica/métodos , Arteria Vertebral/patología , Humanos , Angiografía por Resonancia Magnética , Masculino , Persona de Mediana Edad , Tomógrafos Computarizados por Rayos X
17.
Chin J Traumatol ; 18(1): 41-3, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26169094

RESUMEN

PURPOSE: To compare the therapeutic effects of different doses of intravenous esomeprazole on treating trauma patients with stress ulcer bleeding. METHODS: A total of 102 trauma patients with stress ulcer bleeding were randomly divided into 2 groups: 52 patients were assigned to the high-dose group who received 80 mg intravenous esomeprazole, and then 8 mg/h continuous infusion for 3 days; 50 patients were assigned to the conventional dose group who received 40 mg intravenous esomeprazole sodium once every 12 h for 72 h. RESULTS: Compared with the conventional dose group, the total efficiency of the high-dose group and conventional dose group was 98.08% and 86.00%, respectively (p < 0.05), the hemostatic time was 22.10 h ± 5.18 h and 28.27 h ± 5.96 h, respectively (p < 0.05). CONCLUSION: Both doses of intravenous esomeprazole have good hemostatic effects on stress ulcer bleeding in trauma patients. The high-dose esomeprazole is better for hemostasis.


Asunto(s)
Antiulcerosos/uso terapéutico , Esomeprazol/uso terapéutico , Úlcera Péptica Hemorrágica/tratamiento farmacológico , Úlcera Gástrica/complicaciones , Estrés Psicológico/complicaciones , Heridas y Lesiones/complicaciones , Adolescente , Adulto , Anciano , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Persona de Mediana Edad
18.
Proteomics ; 14(2-3): 169-80, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24307133

RESUMEN

The MS(E) (where MS(E) is low energy (MS) and elevated energy (E) mode of acquisition) acquisition method commercialized by Waters on its Q-TOF instruments is regarded as a unique data-independent fragmentation approach that improves the accuracy and dynamic range of label-free proteomic quantitation. Due to its special format, MS(E) acquisition files cannot be independently analyzed with most widely used open-source proteomic software specialized for processing data-dependent acquisition files. In this study, we established a workflow integrating Skyline, a popular and versatile peptide-centric quantitation program, and a statistical tool DiffProt to fulfill MS(E) -based proteomic quantitation. Comparison with the vendor software package for analyzing targeted phosphopeptides and global proteomic datasets reveals distinct advantages of Skyline in MS(E) data mining, including sensitive peak detection, flexible peptide filtering, and transparent step-by-step workflow. Moreover, we developed a new procedure such that Skyline MS1 filtering was extended to small molecule quantitation for the first time. This new utility of Skyline was examined in a protein-ligand interaction experiment to identify multiple chemical compounds specifically bound to NDM-1 (where NDM is New Delhi metallo-ß-lactamase 1), an antibiotics-resistance target. Further improvement of the current weaknesses in Skyline MS1 filtering is expected to enhance the reliability of this powerful program in full scan-based quantitation of both peptides and small molecules.


Asunto(s)
Proteómica/métodos , Programas Informáticos , Secuencia de Aminoácidos , Minería de Datos , Escherichia coli/química , Proteínas de Escherichia coli/análisis , Ligandos , Espectrometría de Masas/métodos , Datos de Secuencia Molecular , Fosfopéptidos/análisis , Unión Proteica , Proteoma/análisis , beta-Lactamasas/metabolismo
19.
Bioorg Med Chem Lett ; 24(2): 539-47, 2014 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-24365156

RESUMEN

With the emergence of drug resistance and the structural determination of the PA N-terminal domain (PAN), influenza endonucleases have become an attractive target for antiviral therapies for influenza infection. Here, we combined 3D-QSAR with side-chain hopping and molecular docking to produce novel structures as endonuclease inhibitors. First, a new molecular library was generated with side-chain hopping on an existing template molecule, L-742001, using an in-house fragment library that targets bivalent-cation-binding proteins. Then, the best 3D-QSAR model (AAAHR.500), with q(2)=0.76 and r(2)=0.97 from phase modeling, was constructed from 23 endonuclease inhibitors and validated with 17 test compounds. The AAAHR.500 model was then used to select effective candidates from the new molecular library. Combining 3D-QSAR with docking using Glide and Autodock, 13 compounds were considered the most likely candidate inhibitors. Docking studies showed that the binding modes of these compounds were consistent with the crystal structures of known inhibitors. These compounds could serve as potential endonuclease inhibitors for further biological activity tests.


Asunto(s)
Antivirales/química , Antivirales/metabolismo , Diseño de Fármacos , Endonucleasas/antagonistas & inhibidores , Orthomyxoviridae/enzimología , Relación Estructura-Actividad Cuantitativa , Antivirales/farmacología , Sitios de Unión/fisiología , Cristalografía , Endonucleasas/metabolismo , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/metabolismo , Inhibidores Enzimáticos/farmacología , Humanos , Hidroxibutiratos/química , Hidroxibutiratos/metabolismo , Hidroxibutiratos/farmacología , Orthomyxoviridae/efectos de los fármacos , Piperidinas/química , Piperidinas/metabolismo , Piperidinas/farmacología , Estructura Secundaria de Proteína
20.
Bioorg Med Chem ; 22(8): 2416-26, 2014 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-24656804

RESUMEN

A novel series of 1,2-benzisothiazol-3-one derivatives was synthesized and their biological activities were evaluated for inhibiting caspase-3 and -7 activities, in which some of them showed low nanomolar potency against caspase-3 in vitro and significant protection against apoptosis in a camptothecin-induced Jurkat T cells system. Among the tested compounds, compound 5i exhibited the most potent caspase-3 inhibitory activity (IC50=1.15 nM). The molecular docking predicted the interactions and binding modes of the synthesized inhibitor in the caspase-3 active site.


Asunto(s)
Benzotiazoles/química , Caspasa 3/química , Inhibidores de Caspasas/química , Morfolinas/química , Tiazoles/química , Apoptosis/efectos de los fármacos , Benzotiazoles/síntesis química , Benzotiazoles/farmacología , Sitios de Unión , Camptotecina/toxicidad , Caspasa 3/metabolismo , Inhibidores de Caspasas/síntesis química , Inhibidores de Caspasas/farmacología , Dominio Catalítico , Humanos , Células Jurkat , Simulación del Acoplamiento Molecular , Morfolinas/síntesis química , Morfolinas/farmacología , Electricidad Estática , Tiazoles/síntesis química , Tiazoles/farmacología
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