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51.
Isoflavonoids are a class of organic compounds that act primarily as antioxidants. They are produced almost exclusively by various members of the bean family including soybeans, tofu, peanuts, chick peas, and alfalfa. The antioxidant characteristics that isoflavonoids exhibit help hinder the progression of certain cancers, primarily breast, prostate, and colon cancer. We have developed a three-five step synthesis for obtaining a suite of isoflavonoid derivatives. The synthesis involves an enamine formation, a ring closure and halogenation, a Suzuki coupling, and finally a global deprotection to obtain the respective isoflavonoid derivatives. 相似文献
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Mario S. Valds-Tresanco Andrea Molina-Zapata Alaín Gonzlez Pose Ernesto Moreno 《Molecules (Basel, Switzerland)》2022,27(7)
Single domain antibodies from camelids, or nanobodies, are a unique class of antibody fragments with several advantageous characteristics: small monomeric size, high stability and solubility and easy tailoring for multiple applications. Nanobodies are gaining increasing acceptance as diagnostic tools and promising therapeutic agents in cancer and other diseases. While most nanobodies are obtained from immunized animals of the camelid family, a few synthetic nanobody libraries constructed in recent years have shown the capability of generating high quality nanobodies in terms of affinity and stability. Since this synthetic approach has important advantages over the use of animals, the recent advances are indeed encouraging. Here we review over a dozen synthetic nanobody libraries reported so far and discuss the different approaches followed in their construction and validation, with an emphasis on framework and hypervariable loop design as critical issues defining their potential as high-class nanobody sources. 相似文献
55.
Farjadpour A Roundy D Rodriguez A Ibanescu M Bermel P Joannopoulos JD Johnson SG Burr GW 《Optics letters》2006,31(20):2972-2974
Finite-difference time-domain (FDTD) methods suffer from reduced accuracy when modeling discontinuous dielectric materials, due to the inhererent discretization (pixelization). We show that accuracy can be significantly improved by using a subpixel smoothing of the dielectric function, but only if the smoothing scheme is properly designed. We develop such a scheme based on a simple criterion taken from perturbation theory and compare it with other published FDTD smoothing methods. In addition to consistently achieving the smallest errors, our scheme is the only one that attains quadratic convergence with resolution for arbitrarily sloped interfaces. Finally, we discuss additional difficulties that arise for sharp dielectric corners. 相似文献
56.
N. K. Leite J. G. Santos R. F. Souza G. M. Cabianchi F. O. Xavier B. M. Gomes L. B. Silveira A. C. Oliveira A. F.R. Rodriguez P. C. Morais 《The European physical journal. Special topics》2008,153(1):45-48
In this study we demonstrate the usefulness of the
Photoacoustic Spectroscopy (PAS) in the investigation of water collected
from a natural site located within the Amazon region, Brazil, during the wet
to dry seasons transition (May/2006). The water samples were collected from
different stages along a hydrologic pathway including precipitation water
(Prec), groundwater (GW), through flow water (TF), overland flow water (OF),
and stream flow water (SW). The observed photoacoustic spectral features, in
the 0.3 to 1.0 μm wavelength region, fall within three distinct bands
(C, S, and L). We found band-C, band-S and band-L occurring in the spectral
range of 0.30 to 0.40 μm, 0.40 to 0.45 μm and 0.45 to 1.0 μm
regions, respectively. The photoacoustic features shift peak positions and
change intensities for all samples investigated, thus supporting the
proposal of PAS as a useful technique to investigate water samples from
natural environments. 相似文献
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Eladio Rodriguez‐Diaz Danielle Manolakos Holly Christman Michael A. Bonning John K. Geisse Ousama M. A'Amar David J. Leffell Irving J. Bigio 《Photochemistry and photobiology》2019,95(6):1441-1445
Skin cancer is the most prevalent cancer, and its assessment remains a challenge for physicians. This study reports the application of an optical sensing method, elastic scattering spectroscopy (ESS), coupled with a classifier that was developed with machine learning, to assist in the discrimination of skin lesions that are concerning for malignancy. The method requires no special skin preparation, is non‐invasive, easy to administer with minimal training, and allows rapid lesion classification. This novel approach was tested for all common forms of skin cancer. ESS spectra from a total of 1307 lesions were analyzed in a multi‐center, non‐randomized clinical trial. The classification algorithm was developed on a 950‐lesion training dataset, and its diagnostic performance was evaluated against a 357‐lesion testing dataset that was independent of the training dataset. The observed sensitivity was 100% (14/14) for melanoma and 94% (105/112) for non‐melanoma skin cancer. The overall observed specificity was 36% (84/231). ESS has potential, as an adjunctive assessment tool, to assist physicians to differentiate between common benign and malignant skin lesions. 相似文献
60.
Erika Alejandra Martínez-Ortega José Sergio López-Briones Gabriela Rodríguez-Hernández Ricardo Ernesto Ramírez-Orozco 《Natural product research》2020,34(18):2639-2641
AbstractThe objective of this study was to evaluate the antimicrobial effect of Agave fructans against the Salmonella Typhimurium in “in vitro” experiments. The result of the antimicrobial activity was 263.89?±?0, 414.95?±?12.83, 494.54?±?13.88, 522.29?±?0, 580.41?±?14.92?AU for 10, 20, 30, 40 and 50% of Agave fructans (AF) respectively. In addition, there is a significant effect on the growth of the bacteria with all the percentages of AF evaluated (p?<?0.001, R2?=?0.859) with respect to the control. The growth rate of Salmonella with 25% AF was statistically significant compared to the control (?0.7353?±?0.586, 0.0079?±?0.002?D.O./h, respectively; p?>?0.01). Agave fructans could be an alternative to prevent the infections caused by Salmonella. 相似文献