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71.
Anand Jain Giulio Gazzola Aurora Panzera Michele Zanoni Enrico Marsili 《Electrochimica acta》2011,(28):10776
We report visible spectroelectrochemical (SEC) characterization of cytochrome c552 (cyt c552) in viable Geobacter sulfurreducens biofilms on tin-doped indium oxide (ITO) electrodes poised at 0.24 V vs. SHE. G. sulfurreducens biofilms were grown in minimal medium with acetate as electron donor (turnover conditions), followed by 24 h incubation in electron donor-depleted medium (non-turnover conditions). The electronic absorption spectra of G. sulfurreducens biofilms showed the lowest energy absorption band in the reduced state at 552 nm, which indicated excess of cyt c552 in the biofilm. The spectra under non-turnover conditions displayed gradual reduction of the cyt c552, following the step-wise decrease of electrode potential from 0.0 V to −0.6 V vs. standard calomel electrode (SCE). The spectral changes were fully reversible in both positive and negative direction of the scan potential, with average midpoint potential value of −0.42 V vs. SCE. Confocal microscopy analysis revealed that the thickness of biofilms under turnover conditions and non-turnover conditions was approximately 35 and 3.5 μm, respectively. This is the first study to observe the reversible redox conversion of cyt c552 in viable G. sulfurreducens biofilms. 相似文献
72.
Angela Sciacqua Nadia Grillo Michele Quero Giorgio Sesti Francesco Perticone 《International journal of molecular sciences》2012,13(11):13804-13815
It is now well established that major risk factors for cardiovascular diseases (CVD) impact upon endothelial function by decreasing nitric oxide (NO) bioavailability. Asymmetric dimethylarginine (ADMA), an endogenous analog of l-arginine, is able to inhibit the activity of endothelial-NO synthase, promoting endothelial dysfunction. Type 2 diabetes (T2D) is characterized by a reduced endothelium-dependent vasodilation and increased ADMA levels and ADMA is strongly associated with micro- and macrovascular diabetic complications. However, there are not a lot of data about the role of ADMA on endothelial function in newly diagnosed T2D patients without cardiovascular (CV) complications. For this aim, we have enrolled forty-five newly diagnosed T2D patients, evaluated by a oral glucose tolerance test, and thirty normal subjects. Endothelium-dependent and -independent vasodilatation was investigated by intra-arterial infusion of increasing doses of acetylcholine (ACh) and sodium nitroprusside. ADMA was measured by high-performance liquid chromatography and insulin resistance (IR) by HOMA. Newly diagnosed T2D patients showed higher ADMA and l-arginine mean values in comparison with normal subjects and a significantly reduced ACh-stimulated forearm blood flow (FBF). In T2D patients FBF was significantly and inversely correlated with ADMA (r = −0.524, p < 0.0001) and in a multivariate regression analysis, ADMA resulted the stronger predictor of FBF, explaining the 27.5% of variability (p < 0.0001). In conclusion, ADMA was strongly related to endothelial dysfunction also in patients with newly diagnosed T2D, without clinically manifest vascular complications. This field is of great interest for understanding the mechanisms underlying the pathogenesis of diabetic disease and its CV complications. 相似文献
73.
Tim Helbing Caterina Carraro Alexander Francke Dr. Alice Sosic Michele De Franco Prof. Dr. Valentina Gandin Prof. Dr. Richard Göttlich Prof. Dr. Barbara Gatto 《ChemMedChem》2020,15(21):2040-2051
In this study, we describe the synthesis and biological evaluation of a set of bis-3-chloropiperidines (B−CePs) containing rigid aromatic linker structures. A modification of the synthetic strategy also enabled the synthesis of a pilot tris-3-chloropiperidine (Tri-CeP) bearing three reactive meta-chloropiperidine moieties on the aromatic scaffold. A structure–reactivity relationship analysis of B−CePs suggests that the arrangement of the reactive units affects the DNA alkylating activity, while also revealing correlations between the electron density of the aromatic system and the reactivity with biologically relevant nucleophiles, both on isolated DNA and in cancer cells. Interestingly, all aromatic 3-chloropiperidines exhibited a marked cytotoxicity and tropism for 2D and 3D cultures of pancreatic cancer cells. Therefore, the new aromatic 3-chloropiperidines appear to be promising contenders for further development of mustard-based anticancer agents aimed at pancreatic cancers. 相似文献
74.
Dr. Kristina Goncharenko Dr. Michele Mari Dr. Yves P. Auberson Brieuc Matagne 《ChemMedChem》2020,15(24):2359-2362
The European Federation for Medicinal Chemistry (EFMC) created the Young Scientists Network (YSN) to support early-career medicinal chemists and chemical biologists. By doing this, it addressed the rapid changes taking place in the scientific community and in our society, such as the rise of social media, the evolution of the gender balance in the scientific population, and educational needs. Creating the YSN was also a way to ensure that the next generation of scientists would contribute to shaping EFMC's strategy, while recognizing and addressing their needs. The YSN was set up as a very dynamic concept, and has now developed to the point where its impact is evident. The activities it promotes complement EFMC's community support and scientific opportunities, rejuvenating the Federation and preparing it for the future. It also provides opportunities for many brilliant young scientists, who do not hesitate to invest time and energy in supporting our community and shaping their own future. 相似文献
75.
76.
Italia Falcone Fabiana Conciatori Chiara Bazzichetto Emilio Bria Luisa Carbognin Paola Malaguti Gianluigi Ferretti Francesco Cognetti Michele Milella Ludovica Ciuffreda 《International journal of molecular sciences》2020,21(22)
Breast cancer was one of the first malignancies to benefit from targeted therapy, i.e., treatments directed against specific markers. Inhibitors against HER2 are a significant example and they improved the life expectancy of a large cohort of patients. Research on new biomarkers, therefore, is always current and important. AXL, a member of the TYRO-3, AXL and MER (TAM) subfamily, is, today, considered a predictive and prognostic biomarker in many tumor contexts, primarily breast cancer. Its oncogenic implications make it an ideal target for the development of new pharmacological agents; moreover, its recent role as immune-modulator makes AXL particularly attractive to researchers involved in the study of interactions between cancer and the tumor microenvironment (TME). All these peculiarities characterize AXL as compared to other members of the TAM family. In this review, we will illustrate the biological role played by AXL in breast tumor cells, highlighting its molecular and biological features, its involvement in tumor progression and its implication as a target in ongoing clinical trials. 相似文献
77.
78.
Synthesis and Antiplasmodial Activity of Novel Chloroquine Analogues with Bulky Basic Side Chains 下载免费PDF全文
Dr. Bruno Tasso Dr. Federica Novelli Dr. Michele Tonelli Dr. Anna Barteselli Dr. Nicoletta Basilico Dr. Silvia Parapini Prof. Donatella Taramelli Prof. Anna Sparatore Prof. Fabio Sparatore 《ChemMedChem》2015,10(9):1570-1583
Chloroquine is commonly used in the treatment and prevention of malaria, but Plasmodium falciparum, the main species responsible for malaria‐related deaths, has developed resistance against this drug. Twenty‐seven novel chloroquine (CQ) analogues characterized by a side chain terminated with a bulky basic head group, i.e., octahydro‐2H‐quinolizine and 1,2,3,4,5,6‐hexahydro‐1,5‐methano‐8H‐pyrido[1,2‐a][1,5]diazocin‐8‐one, were synthesized and tested for activity against D‐10 (CQ‐susceptible) and W‐2 (CQ‐resistant) strains of P. falciparum. Most compounds were found to be active against both strains with nanomolar or sub‐micromolar IC50 values. Eleven compounds were found to be 2.7‐ to 13.4‐fold more potent than CQ against the W‐2 strain; among them, four cytisine derivatives appear to be of particular interest, as they combine high potency with low cytotoxicity against two human cell lines (HMEC‐1 and HepG2) along with easier synthetic accessibility. Replacement of the 4‐NH group with a sulfur bridge maintained antiplasmodial activity at a lower level, but produced an improvement in the resistance factor. These compounds warrant further investigation as potential drugs for use in the fight against malaria. 相似文献
79.
Matthew L. Breeze Elisa Leyva‐Guerrero Grant R. Yeaman Yelena Dudin Ryan Akel Phil Brune Fred Claussen Cecil Dharmasri Jenny Golbach Rong Guo Carl Maxwell Laura Privalle Hilary Rogers Kai Liu Guomin Shan Michele Yarnall Denise Thiede Nancy Gillikin 《Journal of the American Oil Chemists' Society》2015,92(8):1085-1092
Soybean agglutinin (SBA) protein, also known as soybean lectin, is regarded as an anti‐nutrient due to its negative effect on the ability of monogastric animals to gain weight following consumption of raw soybean seed. Historically, SBA has been measured using a time‐consuming and cumbersome hemagglutination procedure. The objective of our research was to obtain a validated methodology that is precise and accurate in the measurement of SBA while allowing minimally equipped laboratories to effectively conduct the analysis, thus our focus was on evaluating an existing commercially available ELISA, an enzyme‐linked‐lectin‐assay (ELLA), and a hybrid ELISA/ELLA. A new ELLA technique that can detect and quantify lectins was chosen and modified specifically for the quantitation of SBA in soybean seed. The proposed ELLA methodology is similar to a standard sandwich ELISA, and uses polyacrylamide‐linked N‐acetylgalactosamine (Gal–NAc–PAA) for a capture phase and the biotinylated version (Gal–NAc–PAA–Biotin) for detection. Based upon the validation data, the ELLA method can precisely and accurately determine soybean lectin levels in soybean seed. The validated ELLA method was used to quantify SBA in nine commercial soybean varieties introduced between 1972 and 2008 and demonstrated that the natural variability of SBA is subject to the effects of genotype and environment. 相似文献
80.
Polycarbonate‐based composites reinforced by in situ polytetrafluoroethylene fibrillation: Preparation,thermal and rheological behavior 下载免费PDF全文
Diego Antonioli Katia Sparnacci Michele Laus Luca Boarino Maria Cristina Righetti 《应用聚合物科学杂志》2015,132(32)
Fibrillar reinforced composites of polytetrafluoroethylene (PTFE) and polycarbonate (PC) were prepared by in situ fibrillation of PTFE into PC matrix using twin screw extruder. Different samples were obtained by varying the relative ratio between PC and PTFE. The rheological properties of the PC/PTFE composites were found to depend on concentration of the PTFE fibrils. The melt strength analysis in nonisothermal conditions was also studied. The increase in force and decrease in drawability with increasing the PTFE content are associated with the PTFE fibrils formed in situ during the thermomechanical process in twin screw extruder. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42401. 相似文献