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1.
Behav Brain Res ; 466: 114983, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38580200

RESUMO

Humans and other animals exhibit aversive behavioral and emotional responses to unequal reward distributions compared with their conspecifics. Despite the significance of this phenomenon, experimental animal models designed to investigate social inequity aversion and delve into the underlying neurophysiological mechanisms are limited. In this study, we developed a rat model to determine the effects of socially equal or unequal reward and stress on emotional changes in male rats. During the training session, the rats were trained to escape when a sound cue was presented, and they were assigned to one of the following groups: all escaping rats [advantageous equity (AE)], freely moving rats alongside a restrained rat [advantageous inequity (AI)], all restrained rats [disadvantageous equity (DE)], and a rat restrained in the presence of freely moving companions [disadvantageous inequity (DI)]. During the test session, rats in the advantageous group (AE and AI) escaped after the cue sound (expected reward acquisition), whereas rats in the disadvantageous group (DE and DI) could not escape despite the cue being presented (expected reward deprivation). Emotional alteration induced by exposure to restraint stress under various social interaction circumstances was examined using an open field test. Notably, the DI group displayed reduced exploration of the center zone during the open field tests compared with the other groups, indicating heightened anxiety-like behaviors in response to reward inequity. Immunohistochemical analysis revealed increased c-Fos expression in the medial prefrontal and orbitofrontal cortices, coupled with reduced c-Fos expression in the striatum and nucleus accumbens under DI conditions, in contrast to the other experimental conditions. These findings provide compelling evidence that rats are particularly sensitive to reward inequity, shedding light on the neurophysiological basis for distinct cognitive processes that manifest when individuals are exposed to social equity and inequity situations.


Assuntos
Comportamento Animal , Emoções , Proteínas Proto-Oncogênicas c-fos , Estresse Psicológico , Animais , Masculino , Ratos , Comportamento Animal/fisiologia , Sinais (Psicologia) , Emoções/fisiologia , Núcleo Accumbens/metabolismo , Córtex Pré-Frontal/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos Sprague-Dawley , Recompensa , Comportamento Social , Estresse Psicológico/metabolismo , Estresse Psicológico/fisiopatologia
2.
ACS Nano ; 17(18): 17790-17798, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37611120

RESUMO

Oxygen vacancies and adsorbed oxygen species on metal oxide surfaces play important roles in various fields. However, existing methods for manipulating surface oxygen require severe settings and are ineffective for repetitive manipulation. We present a method to manipulate the amount of surface oxygen by modifying the oxygen adsorption energy by electrically controlling the electron concentration of the metal oxide. The surface oxygen control ability of the method is verified using first-principles calculations based on density functional theory (DFT), X-ray photoelectron spectroscopy (XPS), and electrical resistance analysis. The presented method is implemented by fabricating oxide thin film transistors with embedded microheaters. The method can reconfigure the oxygen vacancies on the In2O3, SnO2, and IGZO surfaces so that specific chemisorption dominates. The method can selectively increase oxidizing (e.g., NO and NO) and reducing gas (e.g., H2S, NH3, and CO) reactions by electrically controlling the metal oxide surface to be oxygen vacancy-rich or adsorbed oxygen species-rich. The proposed method is applied to gas sensors and overcomes their existing limitations. The method makes the sensor insensitive to one gas (e.g., H2S) in mixed-gas environments (e.g., NO2+H2S) and provides a linear response (R2 = 0.998) to the target gas (e.g., NO2) concentration within 3 s. We believe that the proposed method is applicable to applications utilizing metal oxide surfaces.

3.
Adv Sci (Weinh) ; 10(30): e2302506, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37651074

RESUMO

Artificial olfactory systems (AOSs) that mimic biological olfactory systems are of great interest. However, most existing AOSs suffer from high energy consumption levels and latency issues due to data conversion and transmission. In this work, an energy- and area-efficient AOS based on near-sensor computing is proposed. The AOS efficiently integrates an array of sensing units (merged field effect transistor (FET)-type gas sensors and amplifier circuits) and an AND-type nonvolatile memory (NVM) array. The signals of the sensing units are directly connected to the NVM array and are computed in memory, and the meaningful linear combinations of signals are output as bit line currents. The AOS is designed to detect food spoilage by employing thin zinc oxide films as gas-sensing materials, and it exhibits low detection limits for H2 S and NH3 gases (0.01 ppm), which are high-protein food spoilage markers. As a proof of concept, monitoring the entire spoilage process of chicken tenderloin is demonstrated. The system can continuously track freshness scores and food conditions throughout the spoilage process. The proposed AOS platform is applicable to various applications due to its ability to change the sensing temperature and programmable NVM cells.


Assuntos
Conservação de Recursos Energéticos , Gases
4.
Curr Microbiol ; 80(4): 119, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36855004

RESUMO

Beef consumption can provide various amino acids, lipids, vitamins, and minerals; however, excessive intake causes metabolic disorders and increases the probability of obesity, atherosclerosis, and colorectal cancer. The intake of omega-3 fatty acids can ameliorate metabolic disorders by lowering blood glucose and triglyceride levels. In the present study, we investigated the effect of omega-3-rich fish oil on body performance and the gut microbiome in a beef-rich diet. Four-week-old C57BL/6 mice were distributed into four groups (chow diet [Chow], chow with beef diet [Beef], chow with omega-3 diet [Cw3], and chow with beef and omega-3 diet [Bw3]). We observed that body weight was unaltered between groups, and serum triglyceride levels were reduced in the omega-3 supplemented groups. The beta diversity indices, unweighted UniFrac distance (P = 0.001), and Jaccard distance (P = 0.001) showed statistically significant differences, and the principal coordinates analysis plot showed a clear separation between groups. In addition, the taxonomic comparison revealed that beef consumption increased numerous potentially pathogenic bacteria, including Escherichia-Shigella, Mucispirillum, Helicobacter, and Desulfovibrio, which were decreased following omega-3 supplementation. Metabolic comparison based on 16S rRNA revealed that energy and glucose metabolism were higher in omega-3 supplemented groups. Our findings suggest that the omega-3 supplementation under intermittent beef consumption contributes to changes in the gut microbiome and microbial metabolic pathways.


Assuntos
Ácidos Graxos Ômega-3 , Microbioma Gastrointestinal , Bovinos , Animais , Camundongos , Camundongos Endogâmicos C57BL , RNA Ribossômico 16S/genética , Óleos de Peixe , Ácidos Graxos Ômega-3/farmacologia , Triglicerídeos
5.
Discov Nano ; 18(1): 24, 2023 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-36829069

RESUMO

The need for high-performance gas sensors is driven by concerns over indoor and outdoor air quality, and industrial gas leaks. Due to their structural diversity, vast surface area, and geometric tunability, metal oxides show significant potential for the development of gas sensing systems. Despite the fact that several previous reports have successfully acquired a suitable response to various types of target gases, it remains difficult to maintain the reliability of metal oxide-based gas sensors. In particular, the degradation of the sensor platform under repetitive operation, such as off-state stress (OSS) causes significant reliability issues. We investigate the impact of OSS on the gas sensing performances, including response, low-frequency noise, and signal-to-noise ratio of horizontal floating-gate field-effect-transistor (FET)-type gas sensors. The 1/f noise is increased after the OSS is applied to the sensor because the gate oxide is damaged by hot holes. Therefore, the SNR of the sensor is degraded by the OSS. We applied a self-curing method based on a PN-junction forward current at the body-drain junction to repair the damaged gate oxide and improve the reliability of the sensor. It has been demonstrated that the SNR degradation caused by the OSS can be successfully recovered by the self-curing method.

6.
Adv Sci (Weinh) ; 10(7): e2205725, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36646505

RESUMO

Concerns about indoor and outdoor air quality, industrial gas leaks, and medical diagnostics are driving the demand for high-performance gas sensors. Owing to their structural variety and large surface area, reducible metal oxides hold great promise for constructing a gas-sensing system. While many earlier reports have successfully obtained a sufficient response to various types of target gases, the selective detection of target gases remains challenging. In this work, a novel method, low-frequency noise (LFN) spectroscopy is presented, to achieve selective detection using a single FET-type gas sensor. The LFN of the sensor is accurately modeled by considering the charge fluctuation in both the sensing material and the FET channel. Exposure to different target gases produces distinct corner frequencies of the power spectral density that can be used to achieve selective detection. In addition, a 3D vertical-NAND flash array is used with the fast Fourier transform method via in-memory-computing, significantly improving the area and power efficiency rate. The proposed system provides a novel and efficient method capable of selectively detecting a target gas using in-memory-computed LFN spectroscopy and thus paving the way for the further development in gas sensing systems.

7.
Psychoneuroendocrinology ; 141: 105752, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35367716

RESUMO

INTRODUCTION: Social buffering is the phenomenon, in which stress and fear reactions caused by exposure to stressful stimuli when animals are exposed to homogeneous relationships are attenuated. Social buffering reduces fear memory behavior such as escape, avoidance, and freezing behavior in rodents due to social existence. Here, we aimed to determine alterations of fear behavior and neural activity in the medial prefrontal cortex (mPFC) in response to the presence of another rat in fear-exposed conditions and to confirm the role of oxytocin in mPFC in regulating social buffering. METHODS: We performed a passive avoidance test and determined positive c-Fos expression in single- and pair-exposed rats. Anisomycin (a protein synthesis inhibitor) and oxytocin receptor regulators (carbetocin; agonist and atosiban; antagonist) were microinjected into the mPFC to clarify the role of oxytocin in the mPFC. RESULTS: While single-exposed rats showed a significant increase in both freezing and passive avoidance behaviors compared to control rats, pair-exposed rats showed significantly less fear behavior compared to single-exposed rats. The c-Fos expression in the prelimbic (PL) mPFC was significantly increased in pair-exposed rats compared to that in control and single-exposed rats. The pair-exposed effect was blocked by anisomycin injections into the PL mPFC of pair-exposed rats. Furthermore, when a carbetocin was injected into the PL mPFC in single-exposed rats, fear behavior was decreased, and these changes were blocked by atosiban. DISCUSSION: Our findings suggest that reduction of fear-related behavior induced by acute pair-exposure is mediated by oxytocin receptors in the PL mPFC. Pair exposure with conspecifics during fear-inducing situations helps coping with fear by significantly increasing the role of oxytocin in the PL mPFC.


Assuntos
Ocitocina , Córtex Pré-Frontal , Animais , Anisomicina/metabolismo , Anisomicina/farmacologia , Medo/fisiologia , Ocitocina/metabolismo , Ocitocina/farmacologia , Córtex Pré-Frontal/metabolismo , Ratos , Receptores de Ocitocina/metabolismo
8.
ACS Appl Mater Interfaces ; 14(15): 17950-17958, 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35385642

RESUMO

Carbon monoxide (CO) poisoning can easily occur in industrial and domestic settings, causing headaches, loss of consciousness, or death from overexposure. Commercially available CO gas sensors consume high power (typically 38 mW), whereas low-power gas sensors using nanostructured materials with catalysts lack reliability and uniformity. A low-power (1.8 mW @ 392 °C), sensitive, selective, reliable, and practical CO gas sensor is presented. The sensor adopts floated WO3 film as a sensing material to utilize the unique reaction of lattice oxide of WO3 with CO gas. The sensor locally modulates the electron concentration in the WO3 film, allowing O2 and CO gases to react primarily in different sensing areas. Electrons generated by the CO gas reaction can be consumed for O2 gas adsorption in a remote area, and this promotes the additional reaction of CO gas, boosting sensitivity and selectivity. The proposed sensor exhibits a 39.5 times higher response than the conventional resistor-type gas sensor fabricated on the same wafer. As a proof of concept, sensors with In2O3 film are fabricated, and the proposed sensor platform shows no advantage in detecting CO gas. Fabrication of the proposed sensor is reproducible and inexpensive due to conventional silicon-based processes, making it attractive for practical applications.

9.
Mater Horiz ; 9(6): 1623-1630, 2022 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-35485256

RESUMO

Gaseous pollutants, including nitrogen oxides, pose a severe threat to ecosystems and human health; therefore, developing reliable gas-sensing systems to detect them is becoming increasingly important. Among the various options, metal-oxide-based gas sensors have attracted attention due to their capability for real-time monitoring and large response. In particular, in the field of materials science, there has been extensive research into controlling the morphological properties of metal oxides. However, these approaches have limitations in terms of controlling the response, sensitivity, and selectivity after the sensing material is deposited. In this study, we propose a novel method to improve the gas-sensing performance by utilizing the remnant polarization of ferroelectric thin-film transistor (FeTFT) gas sensors. The proposed FeTFT gas sensor has IGZO and HZO as the conducting channel and ferroelectric layer, respectively. It is demonstrated that the response and sensitivity of FeTFT gas sensors can be modulated by engineering the polarization of the ferroelectric layer. The amount of reaction sites in IGZO, including electrons and oxygen vacancy-induced negatively charged oxygen, is changed depending on upward and downward polarization. The results of this study provide an essential foundation for further development of gas sensors with tunable sensing properties.


Assuntos
Ecossistema , Poluentes Ambientais , Gases/análise , Humanos , Óxidos , Oxigênio
10.
Biomedicines ; 10(2)2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35203508

RESUMO

Immune checkpoint inhibitor therapy has proven efficacy in a subset of colon cancer patients featuring a deficient DNA mismatch repair system or a high microsatellite instability profile. However, there is high demand for more effective biomarkers to expand the colon cancer population responding to ICI therapy. PBK/TOPK, a serine/threonine kinase, plays a role in cell cycle regulation and mitotic progression. Here, we investigated the correlation between PBK/TOPK expression and tumor immunity and its prognostic value in colon cancer. Based on large-scale bioinformatics analysis, we discovered that elevated PBK/TOPK expression predicted a favorable outcome in patients with colon cancer and was positively associated with immune infiltration levels of CD8+ T cells, CD4+ T cells, natural killer cells, and M1 macrophages. In contrast, a negative correlation was found between PBK/TOPK expression and immune suppressor cells, including regulatory T cells and M2 macrophages. Furthermore, the expression of PBK/TOPK was correlated with the expression of T-cell cytotoxicity genes in colon cancer. Additionally, high PBK/TOPK expression was associated with mutations in DNA damage repair genes, and thus with increased tumor mutation and neoantigen burden. These findings suggest that PBK/TOPK may serve as a prognostic and predictive biomarker for immunotherapy in colon cancer.

11.
Nanoscale ; 13(19): 9009-9017, 2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-33973619

RESUMO

In this paper, we investigate the effects of charge storage engineering (CSE) on the NO2 gas sensing properties such as response, recovery, and sensitivity of a FET-type gas sensor with a horizontal floating-gate (FG) having tungsten trioxide (WO3) as a sensing layer. When the FET transducer is set at an erase state (ΔVth = -2 V), the holes injected into the FG by Fowler-Nordheim (F-N) tunneling increase the electron concentration at the WO3-passivation layer interface. Accordingly, an oxidizing gas, NO2, can take more electrons from WO3, which increases the change in the FG voltage (ΔVFG) by a factor of 2.4. Also, the recovery speed of the sensor in the erase state can be improved by applying pre-bias (Vpre) which is larger than the read bias (Vread). As the carriers in the WO3 film that can interact with NO2 increase by the excess holes stored in the FG by the erase operation, the sensitivity of the sensor also increases 3.2 times. The effects of CSE on various sensing performances are explained using energy band diagrams.

12.
Artigo em Inglês | MEDLINE | ID: mdl-33799474

RESUMO

Postpartum women experience various changes in their physical and psychological health and in their relationships with their spouse and newborn. This study aimed to identify and evaluate the factors that affect the quality of life (QoL) of women within six weeks after childbirth. A prospective, cross-sectional correlational study was used. A convenience sample of 179 postpartum women was recruited from four postpartum care centers in South Korea. Participants completed structured questionnaires on postpartum fatigue, postpartum depression, marital intimacy, breastfeeding adaptation, and quality of life. Marital intimacy (ß = 0.466, p < 0.001) was the most influencing factor on the QoL of women during the postpartum period. In descending order, postpartum fatigue (ß = -0.192, p = 0.001), postpartum depression (ß = -0.190, p = 0.001), breastfeeding adaptation (ß = 0.163, p = 0.002), and occupation (ß = 0.163, p = 0.004) all had a significant influence on QoL (F = 32.09, p < 0.001), and the overall explanatory power was 63.6%. It is necessary to assess and consider the physical, psychological, relational, and demographic factors of women during the early postpartum period. Comprehensive interventions need to be developed to improve the QoL of women during the postpartum period.


Assuntos
Período Pós-Parto , Qualidade de Vida , Estudos Transversais , Feminino , Humanos , Recém-Nascido , Gravidez , Estudos Prospectivos , República da Coreia/epidemiologia , Inquéritos e Questionários
13.
Nanoscale ; 12(38): 19768-19775, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-32966525

RESUMO

In the field of gas sensor studies, most researchers are focusing on improving the response of the sensors to detect a low concentration of gas. However, factors that make a large response, such as abundant or strong adsorption sites, also work as a source of noise, resulting in a trade-off between response and noise. Thus, the response alone cannot fully evaluate the performance of sensors, and the signal-to-noise-ratio (SNR) should additionally be considered to design gas sensors with optimal performance. In this regard, thin-film-type sensing materials are good candidates thanks to their moderate response and noise level. In this paper, we investigate the effects of radio frequency (RF) sputtering power for deposition of sensing materials on the SNR of resistor- and field-effect transistor (FET)-type gas sensors fabricated on the same Si wafer. In the case of resistor-type gas sensors, the deposition conditions that improve the response also worsen the noise either by increasing the scattering at the bulk or damaging the interface of the sensing material. Among resistor-type gas sensors with sensing materials deposited with different RF powers, a sensor with low noise shows the largest SNR despite its small response. However, the noise of FET-type gas sensors is not affected by changes in RF power and thus there is no trade-off between response and noise. The results reveal different noise sources depending on the deposition conditions of the sensing material, and provide design guidelines for resistor- and FET-type gas sensors considering noise for optimal performance.

14.
J Microbiol Biotechnol ; 30(9): 1321-1334, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-32522966

RESUMO

Beef, pork, chicken and milk are considered representative protein sources in the human diet. Since the digestion of protein is important, the role of intestinal microflora is also important. Despite this, the pure effects of meat and milk intake on the microbiome are yet to be fully elucidated. To evaluate the effect of beef, pork, chicken and milk on intestinal microflora, we observed changes in the microbiome in response to different types of dietary animal proteins in vitro. Feces were collected from five 6-week-old pigs. The suspensions were pooled and inoculated into four different media containing beef, pork, chicken, or skim milk powder in distilled water. Changes in microbial communities were analyzed using 16S rRNA sequencing. The feces alone had the highest microbial alpha diversity. Among the treatment groups, beef showed the highest microbial diversity, followed by pork, chicken, and milk. The three dominant phyla were Proteobacteria, Firmicutes, and Bacteroidetes in all the groups. The most abundant genera in beef, pork, and chicken were Rummeliibacillus, Clostridium, and Phascolarctobacterium, whereas milk was enriched with Streptococcus, Lactobacillus, and Enterococcus. Aerobic bacteria decreased while anaerobic and facultative anaerobic bacteria increased in protein-rich nutrients. Functional gene groups were found to be over-represented in protein-rich nutrients. Our results provide baseline information for understanding the roles of dietary animal proteins in reshaping the gut microbiome. Furthermore, growth-promotion by specific species/genus may be used as a cultivation tool for uncultured gut microorganisms.


Assuntos
Proteínas Animais da Dieta/administração & dosagem , Fezes/microbiologia , Microbioma Gastrointestinal , Animais , Bacteroidetes/isolamento & purificação , Bacteroidetes/metabolismo , Bovinos , Galinhas , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Enterococcus/metabolismo , Firmicutes/isolamento & purificação , Firmicutes/metabolismo , Lactobacillus/metabolismo , Carne , Leite/química , Análise de Componente Principal , Proteobactérias/isolamento & purificação , Proteobactérias/metabolismo , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/isolamento & purificação , Análise de Sequência de DNA , Streptococcus/metabolismo , Suínos
15.
J Nanosci Nanotechnol ; 19(10): 6656-6662, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31027006

RESUMO

In this work, we investigate the humidity-sensing performance on a humidity-sensitive p-channel field effect transistor (FET) having a floating-gate (FG) and a control-gate (CG) placing horizontally each other. A sensing layer is formed onto a part of the CG and the O/N/O stack over the FG by inkjet-printing process. The printed ink is composed of indium oxide (In2O3. nanoparticles and dimethylformamide (HCON(CH3)2) as solvent. DC/Pulsed measurements are carried out by switching chamber ambience between dry and humid N2 at 25 °C. Pulsed measurement effectively alleviates the ID drift of the device. When the device is exposed to humidity, the |ID| is appreciably decreased in the p-channel FET-type sensor, since H2O molecules act as an electron donor. The sensitivity of the sensor increases with increasing relative humidity up to about 68% and decreases with further increasing relative humidity.

16.
Nanoscale ; 10(37): 18019-18027, 2018 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-30226514

RESUMO

Oxygen (O2) sensors are needed for monitoring environment and human health. O2 sensing at low temperature is required, but studies are lacking. Here we report, for the first time, that the performance of a field effect transistor (FET)-type O2 sensor operating at 25 °C was improved greatly by a physisorption sensing mechanism. The sensing material was platinum-doped indium oxide (Pt-In2O3) nanoparticles formed by an inkjet printer. The FET-type sensor showed excellent repeatability under a physisorption mechanism and showed much better sensing performance than a resistor-type sensor fabricated on the same wafer at 25 °C. The sensitivity of the sensor increased with increasing Pt concentration up to ∼10% and decreased with further increasing Pt concentration. When the sensing temperature reached 140 °C, the sensing mechanism of the sensor changed from physisorption to chemisorption. Interestingly, the pulse pre-bias before the read bias affected chemisorption but had no effect on physisorption.

17.
Future Med Chem ; 8(8): 853-78, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27195594

RESUMO

Deregulation of EGFR is involved in the development of many cancers. The inhibition of EGFR kinase activity has been clinically validated as a promising approach for the treatment of non-small-cell lung cancer (NSCLC). However, all NSCLC patients who initially benefited from first-generation EGFR inhibitors eventually develop drug resistance. A point mutation at the gatekeeper position, T790M in EGFR kinase domain accounts for more than 50% of acquired resistance. Therefore, second- and third-generation EGFR inhibitors have been developed to overcome the resistance conferred by the gatekeeper mutation. This review has highlighted recent advances in overcoming acquired resistance for the development of each generation of EGFR inhibitors along with their potential issues, and urgent quest for the development of new generation of EGFR inhibitors.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Neoplasias Pulmonares/tratamento farmacológico , Mutação , Inibidores de Proteínas Quinases/farmacologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Proliferação de Células/efeitos dos fármacos , Receptores ErbB/metabolismo , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Inibidores de Proteínas Quinases/química
18.
J Med Chem ; 58(21): 8491-502, 2015 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-26496175

RESUMO

The treatment of activated B cell-like DLBCL (ABC-DLBCL) is one of the urgent unmet medical needs because it is the most resistant DLBCL subtype to current therapies eagerly awaiting effective therapeutic strategies. Recently, the paracaspase MALT1 has emerged as a promising therapeutic target for the treatment of ABC-DLBCL. Herein, we report a new class of MALT1 inhibitors developed by high-throughput screening and structure-based drug design. The original hit, 4-amino-1,2-naphthoquinone series inhibited MALT1 activity but suffered from poor cellular activity. The extensive pharmacophore search led to the discovery of structurally similar ß-lapachone that is a direct inhibitor of MALT1 and possesses favorable physicochemical properties. Molecular simulation studies suggested the possibility of the formation of a covalent bond between MALT1 and ß-lapachone, which was corroborated by experimental wash-out studies. Inspired by this, we explored the structure-activity relationships by incorporating electron-withdrawing substituents at C8 position of ß-lapachone. These MALT1 inhibitors exhibited potent antiproliferative activity to OCI-LY3 cell line and inhibited the cleavage of CYLD mediated MALT1.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Naftoquinonas/química , Naftoquinonas/farmacologia , Proteínas de Neoplasias/antagonistas & inibidores , Caspases/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Linfoma Difuso de Grandes Células B/metabolismo , Modelos Moleculares , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa , Proteínas de Neoplasias/metabolismo , Relação Estrutura-Atividade
19.
Bioorg Med Chem Lett ; 25(22): 5186-9, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-26442778

RESUMO

Enzymatic kinase assays and docking simulation studies have shown that the natural product wrightiadione displays inhibitory activity toward TrkA and PLK3. In this study, the template of wrightiadione served as a starting point for Trk inhibitor development campaigns. Molecular simulation provided structural insights for the design of derivatives that were efficiently generated by our recently developed 3-step tandem synthetic approach, resulting in the discovery of compound 2h with biochemical potency at the single-digit micromolar level.


Assuntos
Antineoplásicos Fitogênicos/química , Indenos/química , Isoflavonas/química , Inibidores de Proteínas Quinases/química , Quinolinas/química , Receptor trkA/antagonistas & inibidores , Humanos , Simulação de Acoplamento Molecular , Receptor trkA/química
20.
Org Lett ; 17(13): 3252-5, 2015 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-26090926

RESUMO

Wrightiadione contains a unique tetracyclic isoflavone moiety and has been shown to exhibit a broad range of biological activities. An efficient and straightforward synthetic method for generating the molecular complexity of wrightiadione was developed through three-step tandem dehydrogenation/oxidation/oxidative cyclization reactions with a Pd/Cu catalytic system. This unprecedented one-pot route utilizes a broad range of substrates, providing a convenient and powerful synthetic tool for accessing naturally occurring tetracyclic isoflavone wrightiadione and its nitrogen-containing derivatives.


Assuntos
Apocynaceae/química , Isoflavonas/síntese química , Catálise , Ciclização , Isoflavonas/química , Estrutura Molecular , Nitrogênio/química , Oxirredução , Casca de Planta/química , Tailândia
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