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1.
Nature ; 581(7809): 401-405, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32461649

RESUMO

Plasmonics enables the manipulation of light beyond the optical diffraction limit1-4 and may therefore confer advantages in applications such as photonic devices5-7, optical cloaking8,9, biochemical sensing10,11 and super-resolution imaging12,13. However, the essential field-confinement capability of plasmonic devices is always accompanied by a parasitic Ohmic loss, which severely reduces their performance. Therefore, plasmonic materials (those with collective oscillations of electrons) with a lower loss than noble metals have long been sought14-16. Here we present stable sodium-based plasmonic devices with state-of-the-art performance at near-infrared wavelengths. We fabricated high-quality sodium films with electron relaxation times as long as 0.42 picoseconds using a thermo-assisted spin-coating process. A direct-waveguide experiment shows that the propagation length of surface plasmon polaritons supported at the sodium-quartz interface can reach 200 micrometres at near-infrared wavelengths. We further demonstrate a room-temperature sodium-based plasmonic nanolaser with a lasing threshold of 140 kilowatts per square centimetre, lower than values previously reported for plasmonic nanolasers at near-infrared wavelengths. These sodium-based plasmonic devices show stable performance under ambient conditions over a period of several months after packaging with epoxy. These results indicate that the performance of plasmonic devices can be greatly improved beyond that of devices using noble metals, with implications for applications in plasmonics, nanophotonics and metamaterials.

2.
J Sep Sci ; 45(2): 492-506, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34799974

RESUMO

Black bean, in which isoflavones are the main active constituent, also contains saponins and monoterpenes. Soybean isoflavone is a secondary metabolite that is formed during the growth of soybean; it exhibits antioxidant and cardiovascular activities and traces estrogen-like effects. In this study, black bean isoflavones were extracted with n-butanol, and ultrafiltration-liquid chromatography-mass spectrometry was used to screen their activity. Subsequently, the inhibitors were isolated and purified using semipreparative liquid chromatography and stepwise flow rate countercurrent chromatography. Thereafter, five active compounds were identified using mass spectrometry and nuclear magnetic resonance experiments. Finally, the inhibition types of the xanthine oxidase inhibitors were determined using enzymatic kinetic studies. The IC50 values of daidzin, glycitein-7-O-glucoside, genistin, daidzein, and genistein were determined to be 35.08, 56.22, 30.76, 68.79, and 95.37 µg/mL, respectively. Daidzin, genistin, and daidzein exhibited reversible inhibition, whereas glycitein-7-O-glucoside and genistein presented irreversible inhibition. This novel approach, which was based on ultrafiltration-liquid chromatography-mass spectrometry and stepwise flow rate countercurrent chromatography, is a powerful method for screening and isolating xanthine oxidase inhibitors from complex matrices. The study of enzyme inhibition types is helpful for understanding the underlying inhibition mechanism. Therefore, a beneficial platform was developed for the large-scale production of bioactive and nutraceutical ingredients.


Assuntos
Distribuição Contracorrente , Isoflavonas , Xantina Oxidase , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida , Isoflavonas/química , Cinética , Phaseolus/química , Proteínas de Plantas/química , Xantina Oxidase/antagonistas & inibidores
3.
Phys Rev Lett ; 125(1): 013903, 2020 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-32678624

RESUMO

Spin-momentum locking is a direct consequence of bulk topological order and provides a basic concept to control a carrier's spin and charge flow for new exotic phenomena in condensed matter physics. However, up to date the research on spin-momentum locking solely focuses on its in-plane transport properties. Here, we report an emerging out-of-plane radiation feature of spin-momentum locking in a non-Hermitian topological photonic system and demonstrate a high performance topological vortex laser based on it. We find that the gain saturation effect lifts the degeneracy of the paired counterpropagating spin-momentum-locked edge modes enabling lasing from a single topological edge mode. The near-field spin and orbital angular momentum of the topological edge mode lasing has a one-to-one far-field radiation correspondence. The methodology of probing the near-field topology feature by far-field lasing emission can be used to study other exotic phenomena. The device can lead to applications in superresolution imaging, optical tweezers, free-space optical sensing, and communication.

4.
Nano Lett ; 18(12): 7942-7948, 2018 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-30422664

RESUMO

Plasmonic nanolasers break the diffraction limit for an optical oscillator, which brings new capabilities for various applications ranging from on-chip optical interconnector to biomedical sensing and imaging. However, the inevitably accompanied metallic absorption loss could convert the input power to heat rather than radiations, leading to undesired low external quantum efficiency and device degradation. To date, direct characterization of quantum efficiency of plasmonic nanolasers is still a forbidden task due to its near-field surface plasmon emissions, divergent emission profile, and the limited emission power. Here, we develop a method to characterize the external quantum efficiency of plasmonic nanolasers by synergizing experimental measurement and theoretical calculation. With systematical device optimization, we demonstrate high performance plasmonic nanolasers with external quantum efficiency exceeding 10% at room temperature. This work fills in a missing yet essential piece of key metrics of plasmonic nanolasers. The demonstrated high external quantum efficiency of plasmonic nanolasers not only clarifies the long-standing debate, but also endorses the exploration of them in various practical applications such as near-field spectroscopy and sensing, integrated optical interconnects, solid-state lighting, and free-space optical communication.

5.
Med Sci Monit ; 24: 9073-9080, 2018 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-30550533

RESUMO

BACKGROUND Serum alkaline phosphatase (ALP) has been proved to be a negative prognostic factor for several malignancies, but its clinical significance in gastric cancer (GC) patients has not been sufficiently studied. In the present retrospective study, we investigated the effect of serum ALP on disease-free survival (DFS) after radical gastrectomy. MATERIAL AND METHODS We included 491 GC patients receiving radical gastrectomy at the Chinese People's Liberation Army 309th Hospital. Univariate and multivariate analyses were performed to determine factors influencing serum ALP and DFS. The changes in serum ALP and its clinical relevance were also analyzed using the log-rank test and Cox proportional hazards model. RESULTS There were 491 patients who met our inclusion and exclusion criteria. Pre-treatment serum ALP was elevated in 87 of these patients and was normal in the other 404 patients. Elevation of pre-treatment serum ALP was correlated with the tumor diameter (OR=2.642, P=0.017), TNM stage (OR=4.592, P=0.005), and T classification (OR=1.746, P=0.043). DFS was significantly different between patients with normal or elevated pre-treatment serum ALP (median 42.1 vs. 32.8 months, P=0.001) and multivariate analysis suggested pre-treatment serum ALP is an independent risk factor for poor DFS after radical gastrectomy (HR=2.035, P=0.021). In addition, removal of the primary tumor lesion led to an obvious decline in serum ALP activity (median 262 U/L vs. 152 U/L, P<0.001), and monitoring changes in serum ALP can help evaluate the risk of tumor relapse in GC patients (χ²=17.814, P<0.001). CONCLUSIONS Serum ALP is a good predictor of GC patient DFS after radical gastrectomy, and patients with elevated serum ALP have shorter relapse times.


Assuntos
Neoplasias Gástricas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Fosfatase Alcalina/análise , Fosfatase Alcalina/sangue , Povo Asiático/genética , Biomarcadores Tumorais/sangue , China , Intervalo Livre de Doença , Feminino , Gastrectomia/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Recidiva Local de Neoplasia , Prognóstico , Intervalo Livre de Progressão , Estudos Retrospectivos , Fatores de Risco
6.
Arch Pharm (Weinheim) ; 351(6): e1700381, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29708285

RESUMO

A novel series of imidazo[4,5-c]pyridine-based CDK2 inhibitors were designed from the structure of CYC202 via scaffold hopping strategy. These compounds were synthesized and biologically evaluated for their CDK2 inhibitory and in vitro anti-proliferation potential against cancer cell lines. Several compounds exhibited potent CDK2 inhibition with IC50 values of less than 1 µM. The most potent compound 5b showed excellent CDK2 inhibitory (IC50 = 21 nM) and in vitro anti-proliferation activity against three different cell lines (HL60, A549, and HCT116). The molecular docking and dynamic studies portrayed the potential binding mechanism between 5b and CDK2, and several key interactions between them were observed, which would be the reason for its potent CDK2 inhibitory and anti-proliferation activities. Therefore, the pyridin-3-ylmethyl moiety would serve as an excellent pharmacophore for the development of novel CDK2 inhibitors for targeted anti-cancer therapy.


Assuntos
Antineoplásicos/farmacologia , Quinase 2 Dependente de Ciclina/antagonistas & inibidores , Imidazóis/farmacologia , Piridinas/farmacologia , Células A549 , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Células HCT116 , Células HL-60 , Humanos , Imidazóis/síntese química , Imidazóis/química , Concentração Inibidora 50 , Simulação de Acoplamento Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Piridinas/síntese química , Piridinas/química , Relação Estrutura-Atividade
7.
Sheng Li Xue Bao ; 70(5): 489-496, 2018 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-30377687

RESUMO

The purpose of the present study was to investigate the effects and underlying mechanism of gonadotropin-releasing hormone agonist (GnRHa) controlled ovarian hyperstimulation (COH) on embryo implantation in mice. Forty female Kunming mice aged 9 weeks were randomly divided into two groups (control and COH groups). The COH group received intraperitoneal (i.p.) injections of aminocyclin acetate (GnRHa), human menopausal gonadotropin (HMG) and human chorionic gonadotropin (hCG), while the control group was given equal amount of physiological saline by i.p. injection. One male mouse and two female mice were put into the same cage at 16:00 on the hCG injection day, and on the fourth day of pregnancy, 10 mice from each group were killed. The levels of serum estradiol (E2) and progesterone (P) were measured by radioimmunoassay; HE staining was used to observe the morphology of ovarian and endometrial tissues. The protein expression levels of endometrial leukemia inhibitory factor (LIF), phosphorylated signal transducer and activator of transcription 3 (p-STAT3), heparin-binding epidermal growth factor-like growth factor (HB-EGF) and glycodelin A were detected by Western blot and immunohistochemistry. Ten mice from each group were sacrificed on the eighth day of pregnancy, and the status of the uterus and the average number of blastocysts were observed. The results showed that, compared with control group, the serum E2 level in COH group was significantly decreased (P < 0.05), while the P level was increased significantly (P < 0.05); the ovarian follicles at different developmental stages were rare, corpus lutea (CL) were visible and multiple, the endometrium was thinned, and the number of endometrial glands was reduced (P < 0.05); the contents of LIF, p-STAT3, HB-EGF and glycodelin A in the endometrium were decreased significantly (P < 0.05) on the fourth day of pregnancy; mouse blastocysts developed slowly and were decreased in number on the eighth day of pregnancy (P < 0.05). The above results suggest that GnRHa COH can affect embryo implantation in mice. The mechanism may be related to the imbalance of gonadal hormone, the changes in the structure of the endometrium and the expressions of LIF, p-STAT3, HB-EGF and glycodelin A in the implantation stage, which may lead to the decrease of endometrial receptivity and the abnormal dialogue between the embryo and the uterus.


Assuntos
Implantação do Embrião/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/agonistas , Minociclina/farmacologia , Indução da Ovulação , Animais , Gonadotropina Coriônica/farmacologia , Endométrio/efeitos dos fármacos , Estradiol/sangue , Feminino , Glicodelina/metabolismo , Humanos , Fator Inibidor de Leucemia/metabolismo , Menotropinas/farmacologia , Camundongos , Folículo Ovariano/efeitos dos fármacos , Gravidez , Progesterona/sangue , Distribuição Aleatória , Fator de Transcrição STAT3/metabolismo
8.
Phys Rev Lett ; 127(20): 209402, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34860064
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(4): 914-8, 2015 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-26197574

RESUMO

In the present paper it was proposed to establish multidimensional scaling linear regression (MDS-MLR) models by combining multidimensional scaling (MDS) with multiple linear regression (MLR), in which MDS owns the ability of dimensionality reduction on spectral variables. Thus the informative spectral wavelengths can be selected for each of the 4 clinical parameters (i. e. glucose, LDL cholesterol, triglycerides and urea) by MDS-MLR method, and the effect of spectral colinearity can be restrained, so that the calibration models can be optimized. Experiments showed that the MDS-MLR models will allow to produce appreciated modeling results when combined with the preprocessing method of moving average (MA). The optimized models were verified by the samples in validation set, and the validating correlation coefficients for each clinical parameter were all upper than 0. 9. These results indicated that FTIR predicted values and the biochemical values of each clinical parameter were highly correlated, which demonstrated that MDS-MLR method has the potential of being applied to the FTIR spectroscopic analysis of human serum. FTIR rapid determination technology combined with the MDS-MLR modeling method is expected to realize the rapid assessment of human health and sub-health level.


Assuntos
Análise Química do Sangue/métodos , Modelos Lineares , Soro/química , Espectroscopia de Infravermelho com Transformada de Fourier , Humanos
10.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 34(3): 317-23, 2014 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-24758084

RESUMO

OBJECTIVE: To explore the potential molecular mechanisms for Bushen Tiaojing Recipe (BTR) improving the endocrine function of ovarian granular cells by observing the effect of BTR containing serum on follicle stimulating hormone/cyclic adenosine monophosphate-protein kinase A (FSH/ cAMP-PKA) pathway in in vitro cultured human ovarian granular cells. METHODS: The primary ovarian granular cells collected from in vitro fertilization-embryo transfer patients were cultured for 24 h. The human and rat serum containing different concentrations of BTR (low, medium, high dose), and their normal serums were co-incubated with ovarian granular cells for 48 h respectively, and then they were divided into the low, medium, high dose BTR groups and the control group. The levels of estradiol (E2), progesterone (P), and cyclic adenosine monophosphate (cAMP) in the culture medium were measured by radioimmunoassay. The protein expression of FSHR in ovarian granular cells was detected by Western Blot. The mRNA expression of follicle stimulating hormone receptor (FSHR) and P450 aromatase (P450arom) in ovarian granular cells were detected by Real-time PCR. RESULTS: In human BTR containing serum groups: Compared with control group, the levels of E2 and cAMP in the culture medium were higher (both P < 0.05) in the medium and high dose BTR groups; the levels of P in the culture medium decreased in the medium dose BTR group (P < 0.01). The protein and mRNA expression of FSHR in ovarian granular cells increased (all P < 0.01), the mRNA expressions of P450arom in ovarian granular cells were higher (P < 0.05, P< 0.01) in the medium and high dose BTR groups. In rat BTR containing serum groups: Compared with the control group, the levels of E2 in the culture medium were higher (all P < 0.01), cAMP in the culture medium were higher (P < 0.05, P < 0.01) in the medium and high dose BTR group; the levels of P in the culture medium decreased in the medium dose BTR group (P < 0.01). The protein and mRNA expression of FSHR in ovarian granular cells were higher (all P < 0.01), the mRNA expression of P450arom in ovarian granular cells increased in the medium and high dose BTR groups (P < 0.05, P < 0.01). CONCLUSION: BTR could possibly improve the endocrine function of ovarian granular cells by regulating main effector molecules FSHR, cAMP, P450arom, and E2 in FSH/cAMP-PKA pathway of ovarian granular cells.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/metabolismo , Células Cultivadas , Proteína Quinase Tipo I Dependente de AMP Cíclico/metabolismo , Feminino , Hormônio Foliculoestimulante/metabolismo , Células da Granulosa/citologia , Humanos , Soro/química , Transdução de Sinais/efeitos dos fármacos
11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(6): 1688-92, 2014 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-25358189

RESUMO

Spectroscopic analysis was applied to the determination of the nutrient quality of ground, instant and chicory coffees. By using inductively coupled plasma atomic emission spectrometry (ICP-ES), nine mineral elements were determined in solid coffee samples. Caffeine was determined by ultraviolet (UV) spectrometry and organic matter was investigated by Fourier transform infrared (FTIR) spectroscopy. Oxidation-reduction titration was utilized for measuring the oxalate. The differences between ground coffee and instant coffee was identified on the basis of the contents of caffeine, oxalate and mineral elements. Experimental evidence showed that, caffeine in instant coffee was 2-3 times higher than in ground coffee. Oxalate in instant coffee was significantly higher in ground coffee. Mineral elements of Mg, P and Zn in ground coffee is lower than in instant coffee, while Cu is several times higher. The mineral content in chicory coffee is overall lower than the instant coffee. In addition, we determined the content of Ti for different types of coffees, and simultaneously detected the elements of Cu, Ti and Zn in chicory coffee. As a fast detection technique, FTIR spectroscopy has the potential of detecting the differences between ground coffee and instant coffee, and is able to verify the presence of caffeine and oxalate.


Assuntos
Cafeína/análise , Coffea/classificação , Café/química , Ácido Oxálico/análise , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Oligoelementos/análise
12.
Iran J Basic Med Sci ; 27(4): 439-446, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38419890

RESUMO

Objectives: Diabetic nephropathy (DN) is the main cause of end-stage renal disease, but the current treatment is not satisfactory. Crocin is a major bioactive compound of saffron with antioxidant and anti-endoplasmic reticulum stress (ERS) abilities used to treat diabetes. This study specifically investigated whether crocin has a regulatory role in renal injury in DN. Materials and Methods: The experiment was divided into control, (db/m mice), model (db/db mice), and experimental groups (db/db mice were intraperitoneally injected with 40 mg/kg crocin). Renal function-related indicators (Scr, BUN, FBG, UP, TG, TC, ALT, and AST) and oxidative stress-related indicators (ROS, MDA, GSH, SOD, and CAT) were assessed. The pathological changes of renal tissues were confirmed by HE, Masson, PAS, and TUNEL staining. The levels of ERS-related proteins (GRP78 and CHOP), apoptosis-related proteins, and PI3K/AKT and Nrf2 pathways-related proteins in renal tissue were detected. Results: In db/db mice, renal function-related indicators, apoptotic cells of renal tissues, the contents of ROS and MDA as well as the expressions of CHOP, GRP78, and Bax were increased, the degree of renal tissue damage was aggravated, while the contents of GSH, SOD, and CAT, as well as the protein levels of Nrf2, PARP, anti-apoptotic proteins (Mcl-1, Bcl-2, Bcl-xl) were decreased compared to the db/m mice. However, crocin treatment reversed the above-mentioned situation. The expressions of the PI3K/AKT and Nrf2 pathways-related proteins were also activated by crocin. Conclusion: Crocin inhibited oxidative stress and ERS-induced kidney injury in db/db mice by activating the PI3K/AKT and Nrf2 pathways.

13.
Histol Histopathol ; : 18741, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38623789

RESUMO

OBJECTIVE: Diabetic nephropathy (DN) is a prevalent cause of end-stage kidney disease worldwide. Moringa isothiocyanate-1 (MIC-1) has shown potential for DN management, however, the exact mechanisms remain unclear. This research intended to evaluate the impact and mechanism of MIC-1 on DN. METHODS: Six C57BLKS/J-db/m mice served as controls. Eighteen C57BLKS/J-db/db mice were randomly separated into three groups: db/db, db/db + irbesartan (IBS), and db/db + MIC-1. Three weeks post-drug administration, the body weight and kidney weight of mice in each group were measured. Concurrently, serum creatinine (Scr), urine albumin, insulin, glycosylated hemoglobin (GHb), oxidative stress-, and inflammatory-related factors were determined. Additionally, the pathological injury, apoptosis, apoptosis-related markers, NLRP3, and ASC levels in the kidney tissues were examined utilizing H&E, Masson, PAS, TUNEL staining, and Western blot. RESULTS: MIC-1 decreased the body weight, kidney weight, the levels of Glu, Scr, and urine albumin in db/db mice. Moreover, MIC-1 significantly suppressed the levels of MDA, insulin, GHb, TNF-α, IL-1ß, and IL-6, while increased the activities of SOD, CAT, and GPX in the serum of db/db mice. MIC-1 also mitigated the kidney tissue injury in db/db mice. Western blot assay showed that MIC-1 enhanced the Bcl-2 level and suppressed the Bax, cleaved caspase-3, cleaved caspase-9, NLRP3, ASC, and caspase-1 levels of the kidney tissues in db/db mice. CONCLUSIONS: MIC-1 ameliorated the kidney injury in DN mice, and its mechanism may be associated with the suppression of renal cell apoptosis, oxidative stress, and inflammatory responses.

14.
Histol Histopathol ; 39(7): 921-934, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38112214

RESUMO

BACKGROUND: NLRP3 inflammasome and Sirt1/autophagy axis are potential targets for advancing acute peritonitis (AP). Honokiol (HNK), a bioactive substance, has the potential to improve AP. MATERIALS AND METHODS: The AP model rats were established by cecal ligation and puncture (CLP). Rats were randomized into the Sham, Sham+HNK, CLP, and CLP+HNK groups. The therapeutic effects of HNK on organ infection, inflammation and immunity were observed in AP rats. The inflammation of RAW 264.7 cells was induced by lipopolysaccharide (LPS) and divided into the Control, HNK, LPS, and LPS+HNK groups. The effects of HNK on immunity and inflammation were observed. Moreover, the inflammatory cell model was further transfected with NLRP3 overexpressing plasmid, and the regulatory effect of HNK on NLRP3 in AP cells was detected. RESULTS: HNK treatment improved survival, biochemical indexes, and lung and kidney injury and inhibited inflammatory cytokine release and bacterial infection in CLP rats. In CLP rats and RAW 264.7 cells, HNK treatment improved the release of the CD4+ and CD8+ T cells, decreased the associated proteins' levels of the NLRP3 inflammasome, and activated the expression of proteins in the Sirt1/autophagy axis. It improved viability and reduced apoptosis and the degrees of TNF-α, IL-1ß, and IL-6 mRNA in RAW 264.7 cells. In addition, HNK treatment antagonized the effect of NLRP3-overexpressed on inflammation and immunity. CONCLUSIONS: HNK improved AP by inhibiting NLRP3 inflammasome and activating the Sirt1 autophagy axis in vivo and in vitro.


Assuntos
Autofagia , Compostos de Bifenilo , Modelos Animais de Doenças , Inflamassomos , Lignanas , Proteína 3 que Contém Domínio de Pirina da Família NLR , Peritonite , Ratos Sprague-Dawley , Sirtuína 1 , Animais , Sirtuína 1/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Autofagia/efeitos dos fármacos , Peritonite/imunologia , Peritonite/tratamento farmacológico , Inflamassomos/metabolismo , Lignanas/farmacologia , Lignanas/uso terapêutico , Camundongos , Ratos , Células RAW 264.7 , Masculino , Compostos de Bifenilo/farmacologia , Compostos de Bifenilo/uso terapêutico , Doença Aguda , Inflamação , Transdução de Sinais/efeitos dos fármacos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Compostos Alílicos , Fenóis
15.
Pigment Cell Melanoma Res ; 37(3): 411-425, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38411373

RESUMO

Uveal melanoma (UM) is the most common primary malignant intraocular tumor in adults. Although primary UM can be effectively controlled, a significant proportion of cases (40% or more) eventually develop distant metastases, commonly in the liver. Metastatic UM remains a lethal disease with limited treatment options. The initiation of UM is typically attributed to activating mutations in GNAQ or GNA11. The elucidation of the downstream pathways such as PKC/MAPK, PI3K/AKT/mTOR, and Hippo-YAP have provided potential therapeutic targets. Concurrent mutations in BRCA1 associated protein 1 (BAP1) or splicing factor 3b subunit 1 (SF3B1) are considered crucial for the acquisition of malignant potential. Furthermore, in preclinical studies, actionable targets associated with BAP1 loss or oncogenic mutant SF3B1 have been identified, offering promising avenues for UM treatment. This review aims to summarize the emerging targeted and epigenetic therapeutic strategies for metastatic UM carrying specific driver mutations and the potential of combining these approaches with immunotherapy, with particular focus on those in upcoming or ongoing clinical trials.


Assuntos
Melanoma , Mutação , Neoplasias Uveais , Neoplasias Uveais/genética , Neoplasias Uveais/patologia , Neoplasias Uveais/terapia , Humanos , Melanoma/genética , Melanoma/patologia , Melanoma/terapia , Mutação/genética , Terapia de Alvo Molecular , Metástase Neoplásica , Animais , Imunoterapia
16.
Protein Expr Purif ; 91(2): 161-8, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23954596

RESUMO

The enzymes involved in riboflavin biosynthesis are considered to be potential anti-bacterial drug targets because these proteins are essential in bacterial pathogens but are absent in humans. 3,4-dihydroxy-2-butanone-4-phosphate synthase (DHBPS) is one of the key enzymes in the biosynthesis of riboflavin. DHBPS catalyzes the conversion of ribulose-5-phosphate (Ru5P) to 3,4-Dihydroxy-2-butanone-4-phosphate (DHBP) and formate. The purified SpDHBPS enzyme, in the presence of Mg(2+) ion, catalyzed the conversion of Ru5P to DHBP at a rate of 109nmolmin(-1)mg(-1) with an apparent Km value of 181µM at 37°C. Surprisingly, our experiments first revealed that DHBPS showed activity in the presence of the trivalent metal ion, Fe(3+). Furthermore, we determined the crystal structure of DHBPS from Gram-positive bacteria, Streptococcus pneumoniae, with 2.0Å resolution. The overall architecture of SpDHBPS was similar to its homologs, which comprise one ß-sheet (five-stranded) and eight α-helices, adopting a three-layered α-ß-α sandwich fold. Similar to the homologs, gel-filtration experiments verified that the enzyme was arranged as a dimer. Although the overall fold of DHBPS was similar, the significant structural differences between the species at the active site region may be utilized to develop antibacterial agents that are species-specific.


Assuntos
Proteínas de Bactérias/química , Transferases Intramoleculares/química , Streptococcus pneumoniae/enzimologia , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Domínio Catalítico , Sistemas de Liberação de Medicamentos , Estabilidade Enzimática , Escherichia coli/genética , Escherichia coli/metabolismo , Transferases Intramoleculares/genética , Transferases Intramoleculares/isolamento & purificação , Transferases Intramoleculares/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Conformação Proteica , Multimerização Proteica , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/metabolismo , Alinhamento de Sequência , Streptococcus pneumoniae/genética
17.
J Tradit Chin Med ; 43(5): 925-933, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37679980

RESUMO

OBJECTIVE: To investigate the outcome of Chinese water-soluble propolis (WSP) on the inflammatory response and oxidative stress (OS) of colonic mucosa in rats with ulcerative colitis. METHODS: Dextran sulfate sodium (DSS) was employed to establish the ucerative colitis (UC) rat model. Forty-eight male rats were arbitrarily separated into six groups, namely control, UC, low-dose water-soluble propolis (L-WSP), medium-dose water-soluble propolis (M-WSP), high-dose water-soluble propolis (H-WSP), and sulfasalazine (Sulfa). In this study, we adopted a method of pre-administration and reconstruction of the model that assessed the water-soluble propolis mediated protection against DSS-induced UC rats. Moreover, we examined the body weight (BW), disease activity index (DAI), bloody stool, colon length, and intestinal mucosal injury index of rats. In addition, using enzyme linked immunosorbent assays, we assessed indicators, such as, colonic myeloperoxidase (MPO), interleukin-6 (IL-6), interleukin-9 (IL-9), tumor necrosis factor-ɑ (TNF-ɑ), superoxide dismutase (SOD), malondialdehyde, and glutathione peroxidase (GSH-Px) levels. RESULTS: The pro-inflammatory cytokine expression, as well as OS, was increased in the model rats. However, upon WSP intervention, both pro-inflammatory cytokine levels and OS reduced dramatically, and the therapeutic effect was dose-dependent. CONCLUSION: WSP downregulates OS by enhancing the function of endogenous antioxidant enzymes like SOD and GSH-Px, that inhibit neutrophil activity, as well as diminish pro-inflammatory cytokines like TNF-ɑ, IL-6, and IL-9, along with mechanisms that attenuate intestinal inflammation in UC rat model.


Assuntos
Colite Ulcerativa , Própole , Masculino , Animais , Ratos , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Interleucina-9 , Interleucina-6/genética , Fator de Necrose Tumoral alfa , Citocinas , Glutationa Peroxidase
18.
BMC Complement Med Ther ; 22(1): 116, 2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35477428

RESUMO

BACKGROUND: Diosmin has been reported to treat diabetes, but its role in diabetic nephropathy (DN) remains unclear. This research investigated the mechanism by which diosmin alleviated high glucose (HG)-induced HK-2 cell injury. METHODS: First, we used CCK-8 to detect the effect of 0.1, 1, or 10 µg/mL diosmin on the viability of HK-2 cells treated with normal glucose or HG. Next, we used flow cytometry, automatic biochemical analyzer, ELISA, immunofluorescence, and colorimetric assay kit to examine the apoptosis, oxidative stress, inflammatory factors, and Caspase-3 expression in HK-2 cells. Thereafter, we used the western blot and qRT-PCR to examine the expression of the endoplasmic reticulum stress-, oxidative stress-, inflammation-, apoptosis-, and autophagy, and PI3K/AKT pathway-related factors. RESULTS: Diosmin was non-cytotoxic to normal HK-2 cells and enhanced the HK-2 cell viability suppressed by HG. Meanwhile, diosmin restrained apoptosis, the contents of MDA, pro-inflammatory factors, and Caspase-3 but intensified the contents of SOD and CAT induced by HG. We further confirmed that diosmin blunted oxidative stress-, inflammation-, apoptosis-, and autophagy-related factors expression induced by HG via restraining the CHOP and GRP78 expressions. Further, we also discovered that PTEN level was restrained and the ratios of p-PI3K/PI3K and p-AKT/AKT were enhanced in HK-2 cells induced by HG, which was reversed by co-treatment of HG and diosmin. CONCLUSIONS: Our study manifested that diosmin alleviated the HG-mediated endoplasmic reticulum stress injury in HK-2 cells via restraining the PI3K/AKT pathway.


Assuntos
Diosmina , Estresse do Retículo Endoplasmático , Caspase 3/metabolismo , Diosmina/farmacologia , Glucose/metabolismo , Humanos , Inflamação/tratamento farmacológico , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais
19.
J Cell Physiol ; 226(6): 1660-75, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21413024

RESUMO

It has been reported that diabetic vascular dysfunction is associated with impaired function of large conductance Ca(2+) -activated K(+) (BK(Ca) ) channels. However, it is unclear whether impaired BK(Ca) channel directly participates in regulating diabetic vascular remodeling by altering cell growth in response to hyperglycemia. In the present study, we investigated the specific role of BK(Ca) channel in controlling apoptosis and proliferation under high glucose concentration (25 mM). The cDNA encoding the α+ß1 subunit of BK(Ca) channel, hSloα+ß1, was transiently transfected into human embryonic kidney 293 (HEK293) cells. Cloned BK(Ca) currents were recorded by both whole-cell and cell-attached patch clamp techniques. Cell apoptosis was assessed with immunocytochemistry and analysis of fragmented DNA by agarose gel electrophoresis. Cell proliferation was investigated by flow cytometry assays, MTT test, and immunocytochemistry. In addition, the expression of anti-apoptotic protein Bcl-2, intracellular Ca(2+) , and mitochondrial membrane potential (Δψm) were also examined to investigate the possible mechanisms. Our results indicate that inhibition of cloned BK(Ca) channels might be responsible for hyperglycemia-altered apoptosis and proliferation in HEK-hSloα+ß1 cells. However, activation of BK(Ca) channel by NS1619 or Tamoxifen significantly induced apoptosis and suppressed proliferation in HEK-hSloα+ß1 cells under hyperglycemia condition. When rat cerebral smooth muscle cells were cultured in hyperglycemia, similar findings were observed. Moreover, the possible mechanisms underlying the activation of BK(Ca) channel were associated with decreased expression of Bcl-2, elevation of intracellular Ca(2+) , and a concomitant depolarization of Δψm in HEK-hSloα+ß1 cells. In conclusion, cloned BK(Ca) channel directly regulated apoptosis and proliferation of HEK293 cell under hyperglycemia condition.


Assuntos
Apoptose/efeitos dos fármacos , Glucose/farmacologia , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta/antagonistas & inibidores , Subunidades beta do Canal de Potássio Ativado por Cálcio de Condutância Alta/antagonistas & inibidores , Animais , Benzimidazóis/farmacologia , Cálcio/metabolismo , Proliferação de Células/efeitos dos fármacos , Clonagem Molecular , Regulação para Baixo/efeitos dos fármacos , Vetores Genéticos/genética , Células HEK293 , Humanos , Ativação do Canal Iônico/efeitos dos fármacos , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta/metabolismo , Subunidades beta do Canal de Potássio Ativado por Cálcio de Condutância Alta/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Peptídeos/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Sprague-Dawley , Tamoxifeno/farmacologia , Transfecção
20.
IEEE Trans Syst Man Cybern B Cybern ; 41(6): 1612-26, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21708503

RESUMO

Co-training is one of the major semi-supervised learning paradigms that iteratively trains two classifiers on two different views, and uses the predictions of either classifier on the unlabeled examples to augment the training set of the other. During the co-training process, especially in initial rounds when the classifiers have only mediocre accuracy, it is quite possible that one classifier will receive labels on unlabeled examples erroneously predicted by the other classifier. Therefore, the performance of co-training style algorithms is usually unstable. In this paper, the problem of how to reliably communicate labeling information between different views is addressed by a novel co-training algorithm named COTRADE. In each labeling round, COTRADE carries out the label communication process in two steps. First, confidence of either classifier's predictions on unlabeled examples is explicitly estimated based on specific data editing techniques. Secondly, a number of predicted labels with higher confidence of either classifier are passed to the other one, where certain constraints are imposed to avoid introducing undesirable classification noise. Experiments on several real-world datasets across three domains show that COTRADE can effectively exploit unlabeled data to achieve better generalization performance.

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