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Metal-semiconductor junctions play an important role in the development of electronic and optoelectronic devices. A Schottky junction photodetector based on two-dimensional (2D) materials is promising for self-powered photodetection with fast response speed and large signal-to-noise ratio. However, it usually suffers from an uncontrolled Schottky barrier due to the Fermi level pinning effect arising from the interface states. In this work, all-2D Schottky junctions with near-ideal Fermi level depinning are realized, attributed to the high-quality interface between 2D semimetals and semiconductors. We further demonstrate asymmetric diodes based on multilayer graphene/MoS2/PtSe2 with a current rectification ratio exceeding 105 and an ideality factor of 1.2. Scanning photocurrent mapping shows that the photocurrent generation mechanism in the heterostructure switches from photovoltaic effect to photogating effect at varying drain biases, indicating both energy conversion and optical sensing are realized in a single device. In the photovoltaic mode, the photodetector is self-powered with a response time smaller than 100 µs under the illumination of a 405 nm laser. In the photogating mode, the photodetector exhibits a high responsivity up to 460 A/W originating from a high photogain. Finally, the photodetector is employed for single-pixel imaging, demonstrating its high-contrast photodetection ability. This work provides insight into the development of high-performance self-powered photodetectors based on 2D Schottky junctions.
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Platelets, produced by megakaryocytes, play unique roles in physiological processes, such as hemostasis, coagulation, and immune regulation, while also contributing to various clinical diseases. During megakaryocyte differentiation, the morphology and function of cells undergo significant changes due to the programmed expression of a series of genes. Epigenetic changes modify gene expression without altering the DNA base sequence, effectively impacting the inner workings of the cell at different stages of growth, proliferation, differentiation, and apoptosis. These modifications also play an important role in megakaryocyte development and platelet biogenesis. However, the specific mechanisms underlying epigenetic processes or the vast epigenetic regulatory network formed by their interactions remain unclear. In this review, we systematically summarize the key roles played by epigenetics in megakaryocyte development and platelet formation, including DNA methylation, histone modification, and non-coding RNA regulation. We expect our review to provide a deeper understanding of the biological processes underlying megakaryocyte development and platelet formation and to inform the development of new clinical interventions aimed at addressing platelet-related diseases and improving patient prognoses.
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Background: Wound healing is a continuous and complex process that comprises multiple phases including hemostasis, inflammation, multiplication (proliferation) and remodeling. Although a variety of nanomaterials have been developed to control infection and accelerate wound healing, most of them can only promote one phase but not multiple phases, resulting in lower efficient healing. Although various formulations such as nitric oxide releasing wound dressings were developed for dual action, the nanostructure synthesis and the encapsulation process were complex. Materials and Methods: Here, we report on the design of graphene-barium titanate nanosystem to procedural promote the wound healing process. The antibacterial effect was assessed in Gram-negative Escherichia coli bacteria (E. coli) and Gram-positive Staphylococcus aureus bacteria (S. aureus), the cell proliferation and migration experiment was investigated in mouse embryonic fibroblast (NIH-3T3) cells, and the wound healing effect was analyzed in female BALB/c mice with infected skin wound on the back. Results: Results showed that graphene-barium titanate nanosystem could generate abundant ROS to kill both E. coli and S. aureus. The growth curves, bacterial viability, colony number formation and scanning electron microscopy (SEM) images of E. coli and S. aureus all confirmed the antibacterial effect. Cell Counting Kit-8 (CCK-8) assay displayed that GBT possesses great biocompatibility. EdU assay showed that GBT plus white light irradiation significantly promoted the proliferation and migration of NIH-3T3 cells. Scratch assay found that GBT could achieve a fast scratch closure compared to the control. In vivo wound healing effect indicates that GBT can accelerate wound repair procedure. Conclusion: GBT nanocomposite is capable of programmatically accelerating wound healing through multiple stages, including production of a large amount of ROS after white light exposure to effectively kill E. coli and S. aureus to prevent wound infection and as a scaffold to accelerate fibroblast proliferation and migration to the wound to accelerate wound healing.
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Grafito , Nanocompuestos , Femenino , Ratones , Animales , Staphylococcus aureus , Grafito/farmacología , Grafito/química , Bario , Escherichia coli , Especies Reactivas de Oxígeno , Fibroblastos , Cicatrización de Heridas , Nanocompuestos/química , Antibacterianos/farmacología , Antibacterianos/químicaRESUMEN
Optical cavities are essential for enhancing the sensitivity of molecular absorption spectroscopy, which finds widespread high-sensitivity gas sensing applications. However, the use of high-finesse cavities confines the wavelength range of operation and prevents broader applications. Here, we take a different approach to ultrasensitive molecular spectroscopy, namely dual-comb optomechanical spectroscopy (DCOS), by integrating the high-resolution multiplexing capabilities of dual-comb spectroscopy with cavity optomechanics through photoacoustic coupling. By exciting the molecules photoacoustically with dual-frequency combs and sensing the molecular-vibration-induced ultrasound waves with a cavity-coupled mechanical resonator, we measure high-resolution broadband ( > 2 THz) overtone spectra for acetylene gas and obtain a normalized noise equivalent absorption coefficient of 1.71 × 10-11 cm-1·W·Hz-1/2 with 30 GHz simultaneous spectral bandwidth. Importantly, the optomechanical resonator allows broadband dual-comb excitation. Our approach not only enriches the practical applications of the emerging cavity optomechanics technology but also offers intriguing possibilities for multi-species trace gas detection.
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BACKGROUND: Triple-negative breast cancer (TNBC) was closely related to high metastatic risk and mortality and has not yet found a targeted receptor for targeted therapy. Cancer immunotherapy, especially photoimmunotherapy, shows promising potential in TNBC treatment because of great spatiotemporal controllability and non-trauma. However, the therapeutic effectiveness was limited by insufficient tumor antigen generation and the immunosuppressive microenvironment. METHODS: We report on the design of cerium oxide (CeO2) end-deposited gold nanorods (CEG) to achieve excellent near-infrared photoimmunotherapy. CEG was synthesized through hydrolyzing of ceria precursor (cerium acetate, Ce(AC)3) on the surface of Au nanorods (NRs) for cancer therapy. The therapeutic response was first verified in murine mammary carcinoma (4T1) cells and then monitored by analysis of the anti-tumor effect in xenograft mouse models. RESULTS: Under near-infrared (NIR) light irradiation, CEG can efficiently generate hot electrons and avoid hot-electron recombination to release heat and form reactive oxygen species (ROS), triggering immunogenic cell death (ICD) and activating part of the immune response. Simultaneously, combining with PD-1 antibody could further enhance cytotoxic T lymphocyte infiltration. CONCLUSIONS: Compared with CBG NRs, CEG NRs showed strong photothermal and photodynamic effects to destroy tumors and activate a part of the immune response. Combining with PD-1 antibody could reverse the immunosuppressive microenvironment and thoroughly activate the immune response. This platform demonstrates the superiority of combination therapy of photoimmunotherapy and PD-1 blockade in TNBC therapy.
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Photoimmunotherapy, with spatiotemporal precision and noninvasive property, has provided a novel targeted therapeutic strategy for highly malignant triple-negative breast cancer (TNBC). However, their therapeutic effect is severely restricted by the insufficient generation of tumor antigens and the weak activation of immune response, which is caused by the limited tissue penetration of light and complex immunosuppressive microenvironment. To improve the outcomes, herein, mace-like plasmonic AuPd heterostructures (Au Pd HSs) have been fabricated to boost near-infrared (NIR) photoimmunotherapy. The plasmonic Au Pd HSs exhibit strong photothermal and photodynamic effects under NIR light irradiation, effectively triggering immunogenic cell death (ICD) to activate the immune response. Meanwhile, the spiky surface of Au Pd HSs can also stimulate the maturation of DCs to present these antigens, amplifying the immune response. Ultimately, combining with anti-programmed death-ligand 1 (α-PD-L1) will further reverse the immunosuppressive microenvironment and enhance the infiltration of cytotoxic T lymphocytes (CTLs), not only eradicating primary TNBC but also completely inhibiting mimetic metastatic TNBC. Overall, the current study opens a new path for the treatment of TNBC through immunotherapy by integrating nanotopology and plasmonic performance.
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Neoplasias de la Mama Triple Negativas , Humanos , Neoplasias de la Mama Triple Negativas/terapia , Neoplasias de la Mama Triple Negativas/patología , Fototerapia , Inmunoterapia , Antígenos de Neoplasias , Microambiente TumoralRESUMEN
Photoacoustic spectroscopy (PAS) using two optical combs is a new-born technique, offering appealing features, including broad optical bandwidths, high resolutions, fast acquisition speeds, and wavelength-independent photoacoustic detection, for chemical sensing. However, its further application to, e.g., trace detection, is jeopardized due to the fundamentally and technically limited sensitivity and specificity. Here, we take a different route to comb-enabled PAS with acoustically enhanced sensitivity and nonlinear spectral hole-burning defined resolution. We demonstrate dual-comb quartz-enhanced PAS with two near-infrared electro-optic combs and a quartz tuning fork. Comb-line-resolved multiplexed spectra are acquired for acetylene with a single-pass detection limit at the parts-per-billion level. The technique is further extended to the mid-infrared (for methane), enabling improved sensitivity. More importantly, we measure nonlinear dual-comb photoacoustic spectra for the 12C2H2 ν1 + ν3 band P(17) transition with sub-Doppler pressure-broadening dominated homogeneous linewidths (e.g., 45.8 MHz), hence opening up new opportunities for Doppler-free photoacoustic gas sensing.
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OBJECTIVE: To evaluate the efficiency of maternal breastfeeding and maternal pain pre- and post-lingual frenulum release procedures in infants with ankyloglossia. METHODS: Infants under 4 months of age with tongue-tie who were actively breastfeeding, and their mothers (mother-infant dyads) were recruited. Infants' ankyloglossia severity was evaluated using the Coryllos® ankyloglossia tongue-tie grading scale. Each mother completed a pre-procedure questionnaire where breastfeeding efficiency was evaluated using the LATCH® criteria. Each mother also reported a numeric score of pain with feeding, breastfeeding time, and a perceived feeding efficiency score. After the tongue-tie release procedure, each mother completed a post-procedure questionnaire within a 1-week to 1-month window to assess the change in breastfeeding efficiency using the LATCH® criteria, breastfeeding pain, breastfeeding time, and perceived breastfeeding efficiency. RESULTS: 41 mother-infant dyads participated in the study. No surgical complications occurred during or post-procedure. All dyads reported improved (40) or equal (1) LATCH® scores: with a mean improved LATCH® score of 3.2 points (p < 4^10-15, 95% CI 2.6, 3.7.). The mean improved maternal perception of feeding was 3.3 points (p < 6^10-10,95% CI 2.6, 4.0.), the mean decreased maternal pain was 4.0 points (p < 1^10-14, 95% CI 3.3, 4.8), and the mean decreased maternal feeding time was 0.80 points (p = 0.002, 95% CI 0.5, 1.1.). CONCLUSION: Lingual frenulum release procedures appear to consistently improve breastfeeding efficiency and decrease maternal pain.
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Anquiloglosia , Anquiloglosia/complicaciones , Anquiloglosia/cirugía , Lactancia Materna , Femenino , Humanos , Lactante , Frenillo Lingual/cirugía , Dolor , Resultado del TratamientoRESUMEN
The COVID-19 pandemic created unprecedented strain on the personal protective equipment (PPE) supply chain. Given the dearth of PPE and consequences for transmission, GetMePPE Chicago (GMPC) developed a PPE allocation framework and system, distributing 886 900 units to 274 institutions from March 2020 to July 2021 to address PPE needs. As the pandemic evolved, GMPC made difficult decisions about (1) building reserve inventory (to balance present and future, potentially higher clinical acuity, needs), (2) donating to other states/out-of-state organizations, and (3) receiving donations from other states. In this case study, we detail both GMPC's experience in making these decisions and the ethical frameworks that guided these decisions. We also reflect on lessons learned and suggest which values may have been in conflict (eg, maximizing benefits vs duty to mission, defined in the context of PPE allocation) in each circumstance, which values were prioritized, and when that prioritization would change. Such guidance can promote a values-based approach to key issues concerning distribution of PPE and other scarce medical resources in response to the COVID-19 pandemic and related future pandemics.
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COVID-19 , Estudios de Casos Organizacionales , Equipo de Protección Personal/provisión & distribución , Asignación de Recursos/ética , Chicago , Toma de Decisiones en la Organización , Humanos , SARS-CoV-2 , Estudiantes de Medicina , VoluntariosRESUMEN
We propose and experimentally demonstrate single-pixel photon counting imaging based on dual-comb interferometry at 1550 nm. Different from traditional dual-comb imaging, this approach enables imaging at the photon-counting regime by using single-photon detectors combined with a time-correlated single-photon counter to record the returning photons. The illumination power is as low as 14 pW, corresponding to 2.2 × 10-3 photons/pulse. The lateral resolution is about 50 µm. This technique paves the way for applying dual-comb in remote sensing and imaging.
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AIMS: Newborns of women with gestational diabetes mellitus (GDM) are susceptible to be macrosomic, even if the blood glucose levels are in normal ranges. The underlying mechanisms are largely unknown. We tested the hypothesis that placental insulin like growth factor(IGF)-I and mammalian target of rapamycin (mTOR) signaling is activated and amino acid transporter expression is increased in women with GDM who give birth to macrosomic babies. METHODS: 50 Chinese pregnant women with GDM whose blood glucose levels were controlled within normal range were recruited and their placental tissues were collected. 23 women gave birth to macrosomia and 27 women gave birth to babies with normal birth weight. We determined the phosphorylation of key signaling molecules (including Akt, IRS-1, S6K1, 4E-BP-1, and AMPKα) in the placental IGF-I and mTOR signaling pathways. We also measured the protein expression of the amino acid transporter systems A in placenta. RESULTS: Birth weights (range 2500-4400â¯g) were positively correlated to maternal IGF-1 (Pâ¯<â¯0.05). The activity of placental IGF-I and mTOR signaling was positively correlated (Pâ¯<â¯0.05), whereas AMPKα phosphorylation was inversely (Pâ¯<â¯0.05) correlated to birth weight. Protein expression of the system A isoform sodium-dependent neutral amino acid transporter (SNAT) 1 were positively correlated to birth weight (Pâ¯<â¯0.05). CONCLUSIONS: Up-regulation of placental amino acid transporters may contribute to more macrosomic babies in women with GDM. Activation of IGF-I and mTOR signaling pathways might involve in this effect.
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Diabetes Gestacional/sangre , Macrosomía Fetal/sangre , Factor I del Crecimiento Similar a la Insulina/efectos adversos , Placenta/metabolismo , Complicaciones del Embarazo/sangre , Serina-Treonina Quinasas TOR/metabolismo , Adulto , Peso al Nacer/fisiología , Femenino , Humanos , Recién Nacido , Factor I del Crecimiento Similar a la Insulina/metabolismo , EmbarazoRESUMEN
PURPOSE: Targeted therapy has brought great clinical benefits for patients with multiple solid tumors, but its effects in patients with locally advanced/metastatic pancreatic cancer (LA/MPC) are disputed. This systematic evaluation compared the efficacy and safety profiles of gemcitabine combined with targeted agents (GEM + TA) versus gemcitabine administered as monotherapy or combined with placebo (GEM ± PLC) in LA/MPC patients. METHODS: PubMed and EMBASE were searched for relevant randomized controlled trials published on or before April 30, 2013. The primary end points were overall survival (OS) and progression-free survival (PFS); the secondary end points were 1-year survival rate, objective response rate (ORR), and toxicity rates (TRs), defined as the prevalence of grade 3/4 adverse events. The systematic evaluation was performed by using Review Manager version 5.1.7. FINDINGS: A total of 10 randomized controlled trials involving 3899 patients (2195 males; mean age, 63.6 years) were included in the systematic evaluation. The results reported that there was no significant difference in OS (hazard ratio [HR] = 0.97 [P = 0.85]), PFS (HR = 0.95 [P = 0.14]), or ORR (odds ratio [OR] = 0.95 [P = 0.69]) between GEM + TA and GEM ± PLC. However, a marginal difference in 1-year survival rate (OR = 0.80 [P = 0.05]) between the 2 groups was observed. The grade 3/4 TRs of anemia, diarrhea, nausea, neutropenia, thrombocytopenia, and vomiting were not significantly different between the 2 groups. However, the prevalence of grade 3/4 rash was significantly greater in the GEM + TA group (OR = 8.31 [P < 0.01]). IMPLICATIONS: Based on the results from this analysis, the addition of targeted agents to a regimen of gemcitabine treatment does not bring survival benefits except 1-year survival rate to patients with LA/MPC.
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Antineoplásicos/uso terapéutico , Desoxicitidina/análogos & derivados , Terapia Molecular Dirigida , Neoplasias Pancreáticas/tratamiento farmacológico , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica , Bases de Datos Bibliográficas , Desoxicitidina/uso terapéutico , Humanos , Masculino , Metaanálisis como Asunto , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto , Análisis de Supervivencia , GemcitabinaRESUMEN
This Letter details the synthesis and evaluation of imidazo[4,5-b]pyridines as inhibitors of B-Raf kinase. These compounds bind in a DFG-in, αC-helix out conformation of B-Raf, which is a binding mode associated with significant kinase selectivity. Structure-activity relationship studies involved optimization of the ATP-cleft binding region of these molecules, and led to compound 23, an inhibitor with excellent enzyme/cell potency, and kinase selectivity.
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Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Purinas/química , Purinas/farmacología , Animales , Células CACO-2 , Diseño de Fármacos , Humanos , Ratones , Simulación del Acoplamiento Molecular , Proteínas Proto-Oncogénicas B-raf/química , Proteínas Proto-Oncogénicas B-raf/metabolismo , Purinas/farmacocinética , Ratas , Relación Estructura-ActividadRESUMEN
Binding of a few ligand molecules with its receptors on cell surface can initiate cellular signaling transduction pathways, and trigger viral infection of host cells. HIV-1 infects host T-cells by binding its viral envelope protein (gp120) with its receptor (a glycoprotein, CD4) on T cells. Primary strategies to prevent and treat HIV infection is to develop therapies (e.g., neutralizing antibodies) that can block specific binding of CD4 with gp120. The infection often leads to the lower counts of CD4 cells, which makes it an effective biomarker to monitor the AIDS progression and treatment. Despite research over decades, quantitative assays for effective measurements of binding affinities of protein-protein (ligand-receptor, antigen-antibody) interactions remains highly sought. Solid-phase electrochemiluminescence (ECL) immunoassay has been commonly used to capture analytes from the solution for analysis, which involves immobilization of antibody on solid surfaces (micron-sized beads), but it cannot quantitatively measure binding affinities of molecular interactions. In this study, we have developed solution-phase ECL assay with a wide dynamic range (0-2 nM) and high sensitivity and specificity for quantitative analysis of CD4 at femtomolar level and their binding affinity with gp120 and monoclonal antibodies (MABs). We found that binding affinities of CD4 with gp120 and MAB (Q4120) are 9.5×108 and 1.2×109 M-1, respectively. The results also show that MAB (Q4120) of CD4 can completely block the binding of gp120 with CD4, while MAB (17b) of gp120 can only partially block their interaction. This study demonstrates that the solution-phase ECL assay can be used for ultrasensitive and quantitative analysis of binding affinities of protein-protein interactions in solution for better understating of protein functions and identification of effective therapies to block their interactions.
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A series of compounds were designed and synthesized as antagonists of cIAP1/2, ML-IAP, and XIAP based on the N-terminus, AVPI, of mature Smac. Compound 1 (GDC-0152) has the best profile of these compounds; it binds to the XIAP BIR3 domain, the BIR domain of ML-IAP, and the BIR3 domains of cIAP1 and cIAP2 with K(i) values of 28, 14, 17, and 43 nM, respectively. These compounds promote degradation of cIAP1, induce activation of caspase-3/7, and lead to decreased viability of breast cancer cells without affecting normal mammary epithelial cells. Compound 1 inhibits tumor growth when dosed orally in the MDA-MB-231 breast cancer xenograft model. Compound 1 was advanced to human clinical trials, and it exhibited linear pharmacokinetics over the dose range (0.049 to 1.48 mg/kg) tested. Mean plasma clearance in humans was 9 ± 3 mL/min/kg, and the volume of distribution was 0.6 ± 0.2 L/kg.
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Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Proteínas Inhibidoras de la Apoptosis/antagonistas & inhibidores , Tiadiazoles/síntesis química , Tiadiazoles/farmacología , Animales , Antineoplásicos/química , Antineoplásicos/farmacocinética , Apoptosis/efectos de los fármacos , Proteína 3 que Contiene Repeticiones IAP de Baculovirus , Unión Competitiva , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Caspasas/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Ensayos Clínicos Fase I como Asunto , Femenino , Humanos , Proteínas Inhibidoras de la Apoptosis/metabolismo , Masculino , Tiadiazoles/química , Tiadiazoles/farmacocinética , Ubiquitina-Proteína LigasasRESUMEN
Recent clinical data provided proof-of-concept for selective B-Raf inhibitors in treatment of B-Raf(V600E) mutant melanoma. Pyrazolopyridine-type B-Raf inhibitors previously described by the authors are potent and selective but exhibit low solubility requiring the use of amorphous dispersion-based formulation for achieving efficacious drug exposures. Through structure-based design, we discovered a new class of highly potent aminopyrimidine-based B-Raf inhibitors with improved solubility and pharmacokinetic profiles. The hinge binding moiety possesses a basic center imparting high solubility at gastric pH, addressing the dissolution limitation observed with our previous series. In our search for an optimal linker-hinge binding moiety system, amide-linked thieno[3,2-d]pyrimidine analogues 32 and 35 (G945), molecules with desirable physicochemical properties, emerged as lead compounds with strong efficacy in a B-Raf(V600E) mutant mouse xenograft model. Synthesis, SAR, lead selection, and evaluation of key compounds in animal studies will be described.
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Aminopiridinas/síntesis química , Antineoplásicos/síntesis química , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Aminopiridinas/farmacocinética , Aminopiridinas/farmacología , Animales , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Línea Celular Tumoral , Cristalografía por Rayos X , Ensayos de Selección de Medicamentos Antitumorales , Ratones , Modelos Moleculares , Estructura Molecular , Trasplante de Neoplasias , Quinazolinas/síntesis química , Quinazolinas/farmacocinética , Quinazolinas/farmacología , Ratas , Solubilidad , Relación Estructura-Actividad , Tiofenos/síntesis química , Tiofenos/farmacocinética , Tiofenos/farmacología , Trasplante HeterólogoRESUMEN
Structure-activity relationships around a novel series of B-Raf(V600E) inhibitors are reported. The enzymatic and cellular potencies of inhibitors derived from two related hinge-binding groups were compared and3-methoxypyrazolopyridine proved to be superior. The 3-alkoxy group of lead B-Raf(V600E) inhibitor 1 was extended and minimally affected potency. The propyl sulfonamide tail of compound 1, which occupies the small lipophilic pocket formed by an outward shift of the αC-helix, was expanded to a series of arylsulfonamides. X-ray crystallography revealed that this lipophilic pocket unexpectedly enlarges to accommodate the bulkier aryl group.
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Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Pirazoles/farmacología , Piridinas/farmacología , Cristalografía por Rayos X , Relación Dosis-Respuesta a Droga , Modelos Moleculares , Estructura Molecular , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/química , Proteínas Proto-Oncogénicas B-raf/metabolismo , Pirazoles/síntesis química , Pirazoles/química , Piridinas/síntesis química , Piridinas/química , Estereoisomerismo , Relación Estructura-ActividadRESUMEN
The V600E mutation of B-Raf kinase results in constitutive activation of the MAPK signaling pathway and is present in approximately 7% of all cancers. Using structure-based design, a novel series of pyrazolopyridine inhibitors of B-Raf(V600E) was developed. Optimization led to the identification of 3-methoxy pyrazolopyridines 17 and 19, potent, selective, and orally bioavailable agents that inhibited tumor growth in a mouse xenograft model driven by B-Raf(V600E) with no effect on body weight. On the basis of their in vivo efficacy and preliminary safety profiles, 17 and 19 were selected for further preclinical evaluation.
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AIM: To elucidate the anticancer mechanism of Huqi San by assessing the expression of G-6-Pase, SDH, ATPase and AFP in N-nitrosodiethylamine-mediated hepatocarcinogenesis in rats. METHODS: A Solt-Farber two-step test model of hepatocarcino genesis was established by diethylnitrosamine (DEN) and 2-acetylaminofluorene (AAF) in rats to investigate the modifying effects of expression of 6-glucosephosphatase (G-6-Pase), succinodehydrogenase (SDH), adenosine triphosphatase (ATPase) in N-nitrosodiethylamine-mediated hepatocarcinogenesis. Hu Qisan compounded by eight medicinal herbs was prepared in glycoprival granules with wich 0.38 g crude herbs/mL solution was prepared for administration. gamma-Glutamy-transpeptidase (gamma-GT), G-6-Pase, SDH and ATPase were immunohistochemically determined. The activity of alpha-fetoglobulin (AFP) in the livers was measured with Immunofluorescence. RESULTS: Huqi San treated rats showed significant decrease in areas of gamma-GT positive foci (P< 0.001). On the other hand, the expression of G-6-Pase, SDH and ATPase has obviously altered in Huqi San treated group. The activity of AFP also significantly decreased after the treatment with Huqi San (8 g/kg body weight or 4 g/kg body weight) or total alkali of mistletoe (0.12 g/kg body weight). CONCLUSIONS: Huqi San can obviously increase these activities of G-6-Pase, SDH and ATPase, and at the same time significantly decrease the expression of gamma-GT and AFP. Therefore, it can obstruct or inhibit the rat's liver preneolastic lesion induced by DEN.
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Dietilnitrosamina/farmacología , Medicamentos Herbarios Chinos/farmacología , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Neoplasias Hepáticas Experimentales/enzimología , 2-Acetilaminofluoreno/metabolismo , Adenosina Trifosfatasas , Animales , Medicamentos Herbarios Chinos/uso terapéutico , Metabolismo Energético/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glucosa-6-Fosfatasa/metabolismo , Hígado/efectos de los fármacos , Hígado/enzimología , Hígado/metabolismo , Neoplasias Hepáticas Experimentales/inducido químicamente , Neoplasias Hepáticas Experimentales/tratamiento farmacológico , Masculino , Ratas , Ratas Wistar , Succinato Deshidrogenasa/metabolismo , gamma-GlutamiltransferasaRESUMEN
AIM: To study the inhibitory effect of Huqi San (Qi-protecting powder) on rat prehepatocarcinoma induced by diethylinitrosamine (DEN) by analyzing the mutational activation of c-fos proto-oncogene and over-expression of c-jun and c-myc oncogenes. METHODS: A Solt-Farber two-step test model of prehepatocarcinoma was induced in rats by DEN and 2-acetylaminofluorene (AAF) to investigate the modifying effects of Huqi San on the expression of c-jun, c-fos and c-myc in DEN-mediated hepatocarcinogenesis. Huqi San was made of eight medicinal herbs containing glycoprival granules, in which each milliliter contains 0.38 g crude drugs. gamma-glutamy-transpeptidase-isoenzyme (gamma-GTase) was determined with histochemical methods. Level of 8-hydroxydeoxyguanosine (OHdG) formed in liver and c-jun, c-fos and c-myc proto-oncogenes were detected by immunohistochemical methods. RESULTS: The level of 8-OHdG, a mark of oxidative DNA damage, was significantly decreased in the liver of rats with prehepatocarcinoma induced by DEN who received 8 g/kg body weight or 4 g/kg body weight Huqi San before (1 wk) and after DEN exposure (4 wk). Huqi San-treated rats showed a significant decrease in number of gamma-GT positive foci (P < 0.001, prevention group: 4.96 +/- 0.72 vs 29.46 +/- 2.17; large dose therapeutic group: 7.53 +/- 0.88 vs 29.46 +/- 2.17). On the other hand, significant changes in expression of c-jun, c-fos and c-myc were found in Huqi San-treated rats. CONCLUSION: Activation of c-jun, c-fos and c-myc plays a crucial role in the pathogenesis of liver cancer. Huqi San can inhibit the over-expression of c-jun, c-fos and c-myc oncogenes and liver preneolastic lesions induced by DEN.