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The photosynaptic transistor stands as a promising contender for overcoming the von Neumann bottleneck in the realm of photo-communication. In this context, photonic synaptic transistors is developed through a straightforward solution process, employing an organic semiconducting polymer with pendant-naphthalene-containing side chains (PDPPNA) in combination with ligand-density-engineered CsPbBr3 perovskite quantum dots (PQDs). This fabrication approach allows the devices to emulate fundamental synaptic behaviors, encompassing excitatory postsynaptic current, paired-pulse facilitation, the transition from short-to-long-term memory, and the concept of "learning experience." Notably, the phototransistor, incorporating the blend of the PDPPNA and CsPbBr3 PQDs washed with ethyl acetate, achieved an exceptional memory ratio of 104. Simultaneously, the same device exhibited an impressive paired-pulse facilitation ratio of 223% at a moderate operating voltage of -4 V and an extraordinarily low energy consumption of 0.215 aJ at an ultralow operating voltage of -0.1 mV. Consequently, these low-voltage synaptic devices, constructed with a pendant side-chain engineering of organic semiconductors and a ligand density engineering of PQDs through a simple fabrication process, exhibit substantial potential for replicating the visual memory capabilities of the human brain.
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BACKGROUND/PURPOSE: A prehospital bypass strategy was suggested for large vessel occlusion. This study aimed to evaluate the effect of a bypass strategy using the gaze-face-arm-speech-time test (G-FAST) implemented in a metropolitan community. METHODS: Pre-notified patients with positive Cincinnati Prehospital Stroke Scale and symptom onset <3 h from July 2016 to December 2017 (pre-intervention period) and those with positive G-FAST and symptom onset <6 h from July 2019 to December 2020 (intervention period) were included. Patients aged <20 years and those with missing in-hospital data were excluded. The primary outcomes were the rates of receiving endovascular thrombectomy (EVT) and intravenous thrombolysis (IVT). The secondary outcomes were total prehospital time, door-to-computed tomography (CT) time, door-to-needle (DTN) time, and door-to-puncture (DTP) time. RESULTS: We included 802 and 695 pre-notified patients from the pre-intervention and intervention periods, respectively. The characteristics of the patients in the two periods were similar. In the primary outcomes, pre-notified patients during the intervention period showed higher rates of receiving EVT (4.49% vs. 15.25%, p < 0.001) and IVT (15.34% vs. 21.58%, p = 0.002). In the secondary outcomes, pre-notified patients during intervention period had longer total prehospital time (mean 23.38 vs 25.23 min, p < 0.001), longer door-to-CT time (median 10 vs 11 min, p < 0.001), longer DTN time (median 53 vs 54.5 min, p < 0.001) but shorter DTP time (median 141 vs 139.5 min, p < 0.001). CONCLUSION: The prehospital bypass strategy with G-FAST showed benefits for stroke patients.
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Isquemia Encefálica , Acidente Vascular Cerebral , Humanos , Administração Intravenosa , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia , Acidente Vascular Cerebral/etiologia , Trombectomia/métodos , Terapia Trombolítica/efeitos adversos , Fatores de Tempo , Tempo para o Tratamento , Resultado do TratamentoRESUMO
We report the design, synthesis, and biological evaluation of 13 new and 1 known anthraquinone derivatives which exerted cytotoxicity against PC3, A549 and NTUB1 cell lines. The results indicate that, among these 14, compounds-1 and 14 showed the highest growth inhibitory effect on NTUB1 and PC3 cells, respectively. Compound-1 at lower doses targets DNA, induces DNA damage and subsequently triggers G2/M arrest and apoptotic cell death at 24 h. Previously we reported that 14 induced PC3 cell autophagy and in treated PC3 cells, cleaved caspase-3 and cleaved PARP, and survivin did not increase and increase, respectively. The autophagic and necrotic cell deaths mediated by 14-triggered ROS generation. Our study is the first to investigate the biological mechanism of 14 action in detail. We find that when 14 was co-administrated with Bafilomycin A1 (BAF) in PC3 cells, rapid necrotic cell death occurred with no cleaved caspase-3 and cleaved PARP activation and increasing the expression of survivin. We further show that necrotic signaling in these cells coincided with production of reactive oxygen species. In the present study, we developed methods to synthesize five new 14 analogues for studing the structure-activity relationships. This study could provide valuable sight to find new antitumor agents for cancer therapy.
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Antraquinonas/farmacologia , Antineoplásicos/farmacologia , Antraquinonas/síntese química , Antineoplásicos/síntese química , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Humanos , Estrutura Molecular , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-AtividadeRESUMO
In order to develop and commercialize for the regenerative medicinal products, smart biomaterials with biocompatibility must be needed. In this chapter, we introduce collagen and hyaluronic acid (HA) as extracellular matrix as well as deal with the molecular mechanism as microenvironment, mechanistic effects, and gene expression. Application of collagen and HA have been reviewed in the area of orthopedics, orthopedics, ophthalmology, dermatology and plastic surgery. Finally, the ongoing and commercial products of collagen and HA for regenerative medicine have been introduced.
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Materiais Biocompatíveis , Colágeno/uso terapêutico , Ácido Hialurônico/uso terapêutico , Medicina Regenerativa/tendências , Matriz Extracelular , HumanosRESUMO
Chondrosarcoma, a common malignant tumour, develops in bone. Effective adjuvant therapy remains inadequate for treatment, meaning poor prognosis. It is imperative to explore novel remedies. Angiogenesis is a rate-limiting step in progression that explains neovessel formation for blood supply in the tumour microenvironment. Numerous studies indicate that EPCs (endothelial progenitor cells) promote angiogenesis and contribute to tumour growth. bFGF (basic fibroblast growth factor), a secreted cytokine, regulates biological activity, including angiogenesis, and correlates with tumorigenesis. However, the role of bFGF in angiogenesis-related tumour progression by recruiting EPCs in human chondrosarcoma is rarely discussed. In the present study, we found that bFGF induced VEGF (vascular endothelial growth factor) expression via the FGFR1 (fibroblast growth factor receptor 1)/c-Src/p38/NF-κB (nuclear factor κB) signalling pathway in chondrosarcoma cells, thereby triggering angiogenesis of endothelial progenitor cells. Our in vivo data revealed that tumour-secreted bFGF promotes angiogenesis in both mouse plug and chick CAM (chorioallantoic membrane) assays. Xenograft mouse model data, due to bFGF-regulated angiogenesis, showed the bFGF regulates angiogenesis-linked tumour growth. Finally, bFGF was highly expressed in chondrosarcoma patients compared with normal cartilage, positively correlating with VEGF expression and tumour stage. The present study reveals a novel therapeutic target for chondrosarcoma progression.
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Neoplasias Ósseas/irrigação sanguínea , Neoplasias Ósseas/metabolismo , Condrossarcoma/irrigação sanguínea , Condrossarcoma/metabolismo , Membrana Corioalantoide/irrigação sanguínea , Células Progenitoras Endoteliais/metabolismo , Fator 2 de Crescimento de Fibroblastos/metabolismo , Neovascularização Patológica , Comunicação Parácrina , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Embrião de Galinha , Condrossarcoma/genética , Condrossarcoma/patologia , Relação Dose-Resposta a Droga , Células Progenitoras Endoteliais/efeitos dos fármacos , Células Progenitoras Endoteliais/patologia , Fator 2 de Crescimento de Fibroblastos/genética , Fator 2 de Crescimento de Fibroblastos/farmacologia , Humanos , Masculino , Camundongos Nus , NF-kappa B/genética , NF-kappa B/metabolismo , Estadiamento de Neoplasias , Neovascularização Fisiológica , Comunicação Parácrina/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Interferência de RNA , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Transdução de Sinais , Transfecção , Carga Tumoral , Regulação para Cima , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Quinases da Família src/antagonistas & inibidores , Quinases da Família src/genética , Quinases da Família src/metabolismoRESUMO
In an effort to develop potent cyclooxygenase-1 (COX-1) inhibitors used as anticancer agent, a series of 2',5'-dimethoxychalcones was screened to evaluate their antiplatelet effect on human washed platelets suspension. Compound 2 exhibited potent inhibition of human washed platelet aggregation induced by collagen, significantly inhibited collagen- and arachidonic acid-induced thromboxane B2 release, and revealed inhibitory effect on COX-1 activity. Molecular docking studies showed that 1, 2, and 4 were bound in the active site of COX-1. These indicated that the antiplatelet effect of these compounds were mainly mediated through the suppression of COX-1 activity and reduced the thromboxane formation. To investigate the mechanistic action of COX-1 inhibitor enhanced the cytotoxic effect against human bladder cancer cells, NTUB1, we assessed the cytotoxic effect of 2 against NTUB1. Treatment of NTUB1 cells with various concentrations of 2 led to a concentration-dependent increase of cell death and decrease of reactive oxygen species levels. The flow-cytometric analysis showed that 2 induced a G1 phase cell cycle arrest but did not accompany an appreciable sub-G1 phase in NTUB1 cells. In addition, compound 2 increased p21 and p27 expressions and did not inhibit the expression of COX-1 in NTUB1 cells. Our results suggested that 2 enhanced cell growth inhibition or antiproliferative activity in NTUB1 cells through G1 arrest by COX-1 independent mechanism.
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Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Chalcona/análogos & derivados , Chalcona/farmacologia , Inibidores da Agregação Plaquetária/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Antineoplásicos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Chalcona/química , Ciclo-Oxigenase 1/metabolismo , Relação Dose-Resposta a Droga , Citometria de Fluxo , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Humanos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Estrutura Molecular , Inibidores da Agregação Plaquetária/química , Espécies Reativas de Oxigênio/metabolismoRESUMO
Ten new lantabetulic acid (1) derivatives 2-11 were synthesized and their cytotoxicities against human prostate cancer cells were evaluated. PC3 cells treated with 10 µM 8 exhibited the most potent G1 phase arrest. In addition, 10 µM 8 markedly decreased the levels of cyclin E and cdk2 and caused an increase in the p21 and p27 levels, while 20 µM 8 mainly led to cell death through the apoptotic pathway, which correlated with an increase in reactive oxygen species levels, decreased expression levels of Bcl-2 and caspase-8, the induction of mitochondrial changes, and decreased levels of cytochrome c in mitochondria. The dual action of 8 could provide a new approach for the development of chemotherapeutic drugs.
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Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Neoplasias da Próstata/patologia , Triterpenos/farmacologia , Antineoplásicos/síntese química , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Desenho de Fármacos , Humanos , Masculino , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Estrutura Molecular , Neoplasias da Próstata/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fatores de Tempo , Triterpenos/síntese químicaRESUMO
BACKGROUND: Tourniquets (TQ) have been increasingly adopted in pre-hospital settings recently. This study examined the effectiveness and safety of applying TQ in the pre-hospital settings for civilian patients with traumatic vascular injuries to the extremities. MATERIALS AND METHODS: We systematically searched the Ovid Embase, PubMed, and Cochrane Central Register of Controlled Trials databases from their inception to June 2023. We compared pre-hospital TQ (PH-TQ) use to no PH-TQ, defined as a TQ applied after hospital arrival or no TQ use at all, for civilian vascular extremity trauma patients. The primary outcome was overall mortality rate, and the secondary outcomes were blood product use and hospital stay. We analyzed TQ-related complications as safety outcomes. We tried to include randomized controlled trials (RCTs) and non-randomized studies (including non-RCTs, interrupted time series, controlled before-and-after studies, cohort studies, and case-control studies), if available. Pooled odds ratios (ORs) were calculated and the certainty of evidence was assessed using Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology. RESULTS: Seven studies involving 4,095 patients were included. In the primary outcome, pre-hospital TQ (PH-TQ) use significantly decrease mortality rate in patients with extremity trauma (odds ratio [OR], 0.48, 95% confidence interval [CI] 0.27-0.86, I2 = 47%). Moreover, the use of PH-TQ showed the decreasing trend of utilization of blood products, such as packed red blood cells (mean difference [MD]: -2.1 [unit], 95% CI: -5.0 to 0.8, I2 = 99%) or fresh frozen plasma (MD: -1.0 [unit], 95% CI: -4.0 to 2.0, I2 = 98%); however, both are not statistically significant. No significant differences were observed in the lengths of hospital and intensive care unit stays. For the safety outcomes, PH-TQ use did not significantly increase risk of amputation (OR: 0.85, 95% CI: 0.43 to 1.68, I2 = 60%) or compartment syndrome (OR: 0.94, 95% CI: 0.37 to 2.35, I2 = 0%). The certainty of the evidence was very low across all outcomes. CONCLUSION: The current data suggest that, in the pre-hospital settings, PH-TQ use for civilian patients with vascular traumatic injury of the extremities decreased mortality and tended to decrease blood transfusions. This did not increase the risk of amputation or compartment syndrome significantly.
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Torniquetes , Lesões do Sistema Vascular , Humanos , Lesões do Sistema Vascular/mortalidade , Extremidades/lesões , Extremidades/irrigação sanguínea , Serviços Médicos de Emergência/métodosRESUMO
BACKGROUND: An updated overview of ultrasound (US) for diagnosis of acute cholecystitis (AC) remains lacking. This systematic review was conducted to evaluate the diagnostic performance of US for AC. METHODS: A systematic review was conducted following PRISMA guidelines. We meticulously screened articles from MEDLINE, Embase, and the Cochrane Library, spanning from inception to August 2023. We employed the search strategy combining the keywords "bedside US", "emergency US" or "point-of-care US" with "AC". Two reviewers independently screened the titles and abstracts of the retrieved articles to identify suitable studies. The inclusion criteria encompassed articles investigating the diagnostic performance of US for AC. Data regarding diagnostic performance, sonographers, and sonographic findings including the presence of gallstone, gallbladder (GB) wall thickness, peri-GB fluid, or sonographic Murphy sign were extracted, and a meta-analysis was executed. Case reports, editorials, and review articles were excluded, as well as studies focused on acalculous cholecystitis. The study quality was assessed with the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool. RESULTS: Forty studies with 8,652 patients were included. The majority of studies had a low risk of bias and applicability concerns. US had a pooled sensitivity of 71% (95% CI, 69-72%), a specificity of 85% (95% CI, 84-86%), and an accuracy of 0.83 (95% CI, 0.82-0.83) for the diagnosis of AC. The pooled sensitivity and specificity were 71% (95% CI, 67-74%) and 92% (95% CI, 90-93%) performed by emergency physicians (EPs), 79% (95% CI, 71-85%) and 76% (95% CI, 69-81%) performed by surgeons, and 68% (95% CI 66-71%) and 87% (95% CI, 86-88%) performed by radiologists, respectively. There were no statistically significant differences among the three groups. CONCLUSION: US is a good imaging modality for the diagnosis of AC. EP-performed US has a similar diagnostic performance to radiologist-performed US. Further investigations would be needed to investigate the impact of US on expediting the management process and improving patient-centered outcomes.
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Colecistite Aguda , Humanos , Colecistite Aguda/diagnóstico por imagem , Ultrassonografia/métodos , Sensibilidade e EspecificidadeRESUMO
Aim: The mobile network quality in ambulances can be variable and limited. This pilot study aimed to identify a suitable network setting for recognizing agonal respiration under limited network conditions. Methods: We recruited five emergency medical technicians, and each participant viewed 30 real-life videos with different resolutions, frame rates, and network scenarios. Thereafter, they reported the respiration pattern of the patient and identified agonal respiration cases. The time at which agonal respiration was identified was also recorded. The answers provided by the five participants were compared with those of two emergency physicians to compare the accuracy and time delay in breathing pattern recognition. Results: The overall accuracy for initial respiratory pattern recognition was 80.7% (121/150). The accuracy for normal breathing was 93.3% (28/30), for not breathing was 96% (48/50), and for agonal breathing was 64.3% (45/70). There was no significant difference in successful recognition between video resolutions. However, the rate of time delay in recognizing agonal respiration less than 10 seconds between 15-fps group and 30-fps group had statistical significance (21% vs 52%, p = 0.041). Conclusion: The frame rate emerges as one of critical factors in agonal respiration recognition through telemedicine, outweighing the significance of video resolution.
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A novel chromone analogue, phyllomakin A (1), and a new flavonolignan, (-)-quiquelignan C (2), along with 18 phenolic and 2 triterpenoids, were isolated from the leaves of Phyllostachys makinoi Hayata. The structures of 1-22 were elucidated by an application of various spectroscopic analyses (1D & 2D NMR and MS) and compared with reported data. A biological evaluation showed that compound 3 had very potent anti-NO production activity (IC50 = 4.80 µM), while compounds 2, 6, 11, and 15 showed moderate inhibitory effects (IC50 = 10.19, 13.26, 13.56, and 10.96 µM, respectively) without affecting cell viability at 20 µM.
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Anti-Inflamatórios , Triterpenos , Anti-Inflamatórios/química , Estrutura Molecular , Fenóis/análise , Folhas de Planta/química , Análise Espectral , Triterpenos/químicaRESUMO
Twenty six 18ß-glycyrrhetinic acid (GA) (1) derivatives 2-27 including twelve new GA derivatives 10, 11, 13-17, 21-25 were synthesized and evaluated for cytotoxicities against NTUB1 cells (human bladder cancer cell lines). seco-Compounds 9, 25, and 27 are the most potent compounds of this series, inhibiting cell growth of human NTUB1 cells with an IC(50) values of 2.34 ± 0.28, 4.76 ± 1.15, and 3.31 ± 0.61 µM, respectively. Exposure of NTUB1 to 25 for 24h significantly increased the production of reactive oxygen species (ROS). Flow cytometric analysis exhibited that treatment of NTUB1 with 25 did not induce cell cycle arrest but accompanied by an increase of apoptotic cell death in a dose-dependant manner after 24h. Mitochondrial membrane potential (MMP) decreased significantly in a dose-dependant manner when the NTUB1 cells were exposed to 25 for 24h. Marked collapse of the MMP suggested that dysfunction of the mitochondria may be involved in the oxidative burst and apoptosis induced by 25. Western blot analysis shows that NTUB1 cells treated with 25 increased the level of p-p53 in a dose-dependant manner. Further, NAC treatment prevented p53 phosphorylation stimulated by 25. These results suggested that 25 induced a mitochondrial-mediated apoptosis in NTUB1 cells through activation of p53, which are mainly mediated ROS generated by 25.
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Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Ácido Glicirretínico/análogos & derivados , Mitocôndrias/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Ácido Glicirretínico/síntese química , Ácido Glicirretínico/química , Ácido Glicirretínico/farmacologia , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/metabolismo , Conformação Molecular , Estereoisomerismo , Relação Estrutura-Atividade , Células Tumorais CultivadasRESUMO
Because of the high prevalence and association of somatic symptoms in depression, a holistic treatment plan that also targets the associated somatic symptoms can be the cornerstone for such patients. In this paper, we present the case of a 53-year-old male physician with depression associated with the somatic symptoms of dysphagia. The initial failure in treating his swallowing defect led to the deterioration in his condition. Moreover, his unique history, complicated by multifactorial life stressors, also raises the attention that there are a variety of presentations of depression.
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A series of omega-aminoalkoxylxanthones was synthesized and tested in vitro for their ability to inhibit platelet aggregation and cause vasorelaxing action. Compounds 4, 5, 12, 17, and 18 showed significant antiplatelet effects on thrombin-, arachidonic acid (AA)-, collagen-, and platelet activating factor (PAF)-induced washed rabbit platelet aggregation and exhibited inhibition of primary and secondary aggregation induced by adenosine-5'-diphosphate (ADP) in human platelet-rich-plasma (PRP). Compounds 4, 17, and 18 revealed vasorelaxing activities in rat thoracic aorta. We concluded that these compounds may be developed as new antithrombotic agents.
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Fibrinolíticos/síntese química , Inibidores da Agregação Plaquetária/síntese química , Vasodilatadores/síntese química , Xantonas/síntese química , Animais , Aorta/efeitos dos fármacos , Aorta/fisiologia , Células Cultivadas , Humanos , Agregação Plaquetária/efeitos dos fármacos , Coelhos , Ratos , Relação Estrutura-Atividade , Vasodilatação/efeitos dos fármacos , Xantonas/química , Xantonas/farmacologiaRESUMO
By an ESI-LC/MS analytical method, a racemate 1 consisting of a pair of unprecedented phloroglucinol enantiomers with a 5/6/5/5/6 fused ring system, (-)-garcinielliptone HG [((-)-1a] and (+)-garcinielliptone HH [(+)-1b], was obtained from the isolates of a CH2Cl2 extract of Garcinia subelliptica (heartwood). The gross structure of 1 was elucidated by spectroscopic methods and X-ray single-crystal diffraction data. The absolute configurations of 1a and 1b were unequivocally assigned by analysis on the calculated and experimental circular dichroism spectra and X-ray single-crystal diffraction data.
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The ability of flavonoid glycosides isolated from several plants to induce DNA breakage was examined using supercoiled plasmid pBR322 DNA by agarose gel electrophoresis in the presence of Cu(II). Among all the compounds, 1, 4, and 6 could cause significant breakages of supercoiled plasmid pBR322 DNA in the presence of Cu(II). Cu(I) was not shown to be an essential intermediate in the process of pBR322 DNA breakage by using the Cu(I)-specific sequestering reagent neocuproine. A decreased cell viability was enhanced in gastric carcinoma SCM-1 cells treating with lower concentrations of 1 and 6 when cotreated with increased concentrations of Cu(II), respectively. Treatments of SCM-1 cells with 500 microM of 1 in the presence of 300 or 500 microM of Cu(II) inhibited the Cu(II)-induced apoptosis. Compound 1 (500 microM) could prevent cell death by inhibiting the 500 microM Cu(II)-induced apoptosis and necrosis, but did not have any effect on the mitochondrial membrane potential changed by 500 microM Cu(II). Both compounds 1 and 6 could inhibit the DNA breakages caused by O2- while 1 also revealed inhibitory effect on xanthine oxidase with an IC50 value of 22.7+/-6.9 microM. These results indicated that compound 1 with a higher concentration may probably mediate through the suppression of xanthine oxidase activity and reduce reactive oxygen species (ROS) induced by high concentration of Cu(II) (500 microM) and prevent the following cell death.
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Apoptose/efeitos dos fármacos , Cobre/farmacologia , Dano ao DNA/efeitos dos fármacos , DNA Super-Helicoidal/efeitos dos fármacos , Flavonoides/farmacologia , Glicosídeos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Cobre/química , Quebras de DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Interações Medicamentosas , Eletroforese em Gel de Ágar , Flavonoides/química , Sequestradores de Radicais Livres , Radicais Livres , Glicosídeos/química , Humanos , Potenciais da Membrana/efeitos dos fármacos , Oxirredução , Plasmídeos , Células Tumorais Cultivadas , Xantina Oxidase/antagonistas & inibidoresRESUMO
The autophagy of human prostate cancer cells (PC3 cells) induced by a new anthraquinone derivative, 1-Hydroxy-3-[(E)-4-(piperazine-diium)but-2-enyloxy]-9,10-anthraquinone ditrifluoroactate (PA) was investigated, and the relationship between autophagy and reactive oxygen species (ROS) generation was studied. The results indicated that PA induced PC3 cell death in a time- and dose-dependent manner, could inhibit PC3 cell growth by G1 phase cell cycle arrest and corresponding decrease in the G2/M cell population and induced S-phase arrest accompanied by a significant decrease G2/M and G1 phase numbers after PC3 cells treated with PA for 48â¯h, and increased the accumulation of autophagolysosomes and microtubule-associated protein LC3-ll, a marker of autophagy. However, these phenomenon were not observed in the group pretreated with the autophagy inhibitor 3-MA or Bafilomycin A1 (BAF), suggesting that PA induced PC3 cell autophagy. In addition, we found that PA triggered ROS generation in cells, while the levels of ROS decreased in the N-acetylcysteine (NAC) co-treatment, indicating that PA-mediated autophagy was partly blocked by NAC. In summary, the autophagic cell death of human PC3 cells mediated by PA-triggered ROS generation.
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Antraquinonas/toxicidade , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Acetilcisteína/farmacologia , Adenina/análogos & derivados , Adenina/farmacologia , Antraquinonas/síntese química , Antraquinonas/química , Caspase 3/metabolismo , Linhagem Celular Tumoral , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Humanos , Macrolídeos/farmacologia , Microscopia Eletrônica de Transmissão , Proteínas Associadas aos Microtúbulos/metabolismo , Espécies Reativas de Oxigênio/metabolismoRESUMO
Ganoderma tsugae is a medicinal mushroom. In a continual study on the bioactive constituents of this fungus, a new lanostanoid, 3ß-acetoxy-16α-hydroxy-24ξ-methyl-5α-lanosta-8,25-dien-21-oic acid, named tsugaric acid F (1) and a novel palmitamide, N-(3'α,4'ß-dihydroxy-2'ß-(hydroxymethyl)-1'ß-(cyclobutyl)palmitamide (2) were isolated and characterized from the fruit bodies of G. tsugae, and three novel seco-lanostanoids, 3,4-seco-8α,9α-epoxy-5α-lanosta-21-oic acid 3,4 lactone (5), 3,4-seco-5ß-lanosta-7,9(11),4(29)-trien-3,21-dioic acid-3-methyl ester (6), 3,4-seco-5ß-lanosta-7,9(11),4(29)-trien-3,21-dioic acid (7), and a known compound, 3-oxo-5α-lanosta-8-en-21-oic acid (4) were prepared from 3. The structures of new compounds, 1, 2, 5-7 were determined by spectroscopic methods. Compounds 1 and 4 showed inhibitory effects on xanthine oxidase (XO) with an IC50 values of 313.3 ± 80.0 and 43.9 ± 29.9 µM, respectively when 7 exhibited potent inhibitory effect on superoxide anion generation in rat neutrophils stimulated with formyl-Met-Leu-Phe (fMLP)/cytochalasin B (CB) with an IC50 values of 1.3 ± 0.2 µM. Compounds 4-7 showed weak cytotoxic activities against PC3 cells. These results indicated that 4 and 7 may be used as cancer chemopreventive agents.
Assuntos
Amidas/química , Ganoderma/química , Triterpenos/química , Agaricales/química , Amidas/isolamento & purificação , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Concentração Inibidora 50 , Camundongos , Estrutura Molecular , Neutrófilos/efeitos dos fármacos , Células RAW 264.7 , Ratos , Triterpenos/isolamento & purificação , Xantina Oxidase/antagonistas & inibidoresRESUMO
Although p73 is a structural and functional homologue of the tumor-suppressor gene p53, it is not mutated in many human cancers as p53. Besides, p73 was shown to be activated by only a subset of signals that activate p53, such as gamma-irradiation and cisplatin, but not by other common genotoxic stress-inducing agents such as ultraviolet (UV) irradiation, although many of these signals are also capable of inducing p53-independent cell death. Using a p73-specific antibody, we confirmed that c-Abl is required for cisplatin-induced p73 upregulation, and further demonstrate that the p73 protein is upregulated by UV irradiation and other stress stimuli including sorbitol, hydrogen peroxide, nocodazol, and taxol. These stress signals upregulate both p73 mRNA and increases the stability of p73, indicating that p73 is regulated transcriptionally and posttranslationally. Cells stably expressing the dominant-negative p73 inhibitor protein (p73DD) and p73(-/-) fibroblasts are more resistant than control cells to apoptosis induced by these stress signals, suggesting that p73 contributes to apoptosis induction. Together, the data demonstrate that several stress signals can signal to p73 in vivo, which raises the possibility of eradicating cancers with an unmutated p73 gene by activating them with stress-inducing agents or their mimetics.