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The volatile composition of 10 endemic Cephalaria (Dipsacaceae) species (Cephalaria gazipashensis, Cephalaria lycica, Cephalaria paphlagonica, Cephalaria elmaliensis, Cephalaria stellipilis, Cephalaria scoparia, Cephalaria isaurica, Cephalaria cilicica, Cephalaria elazigensis var. purpurea and Cephalaria davisiana) was investigated. The essential oil mixtures were obtained by steam distillation in a Clevenger-type apparatus. Twenty-eight components were identified by GC-FID and GC-MS techniques. While total volatile percentages ranged from 68.99% to 84.57%, the total essential oil yields ranged between 38.15% and 64.05%. Geraniol, α-cedrene and p-cymene were determined as the main components. Geraniol was detected as a major component in C. cilicica (14.64%), and α-cedrene was detected as a major component with 26.03% for C. lycica, 16.93% for C. scoparia, 13.01% for C. davisiana and 10.94% for C. paphlagonica. Cephalaria scoparia, C. davisiana and C. gazipashensis have considerable amount of p-cymene as 12.86%, 12.70% and 11.16%, respectively. This was the first essential oil report concerning the Cephalaria genus. [ABSTRACT FROM AUTHOR]

The clinical impact and accessibility of 99m Tc tracers for cancer diagnosis would be greatly enhanced by the availability of a new, simple, and easy labeling process and radiopharmaceuticals. 5-Fluorouracil is an antitumor drug, which has played an important role for the treatment of breast carcinoma. In the present study, a new derivative of 5-Fluorouracil was synthesized as (1-[{1'-(1''-deoxy-2'',3'':4'',5''-di-O-isopropylidene-β-D-fructopyranose-1''-yl)-1'H-1',2', 3'-triazol-4'-yl}methyl]-5-fluorouracil) (E) and radiolabeled with 99m Tc. It was analyzed by radio thin layer chromatography for quality control and stability. The radiolabeled complex was subjected to in vitro cell-binding studies to determine healthy and cancer cell affinity using HaCaT and MCF-7 cells, respectively. In addition, in vitro cytotoxicity studies of compound E were performed with HaCaT and MCF-5 cells. The radiochemical purity of the [ 99m Tc]TcE was found to be higher than 90% at room temperature up to 6 hours. The radiolabeled complex showed higher specific binding to MCF-7 cells than HaCaT cells. IC 50 values of E were found 31.5 ± 3.4 μM and 20.7 ± 2.77 μM for MCF-7 and HaCaT cells, respectively. The results demonstrated the potential of a new radiolabeled E with 99m Tc has selective for breast cancer cells., (© 2019 John Wiley & Sons, Ltd.)

The use of calixarenes in asymmetric catalysis is receiving increasing attention due to their tunable three-dimensional molecular platforms along with their easy syntheses and versatile modification at the upper and lower rims. This review summarizes the recent progress of synthesis and use of chiral calixarenes in asymmetric syntheses which emerged later than 2010.

5-Fluorouracil is one of the first line drugs for the systemic therapy of solid tumors like breast, colorectal, oesophageal, stomach, pancreatic, head and neck. It could be shown that sugars can improve the absorption across cell membranes and can help to bypass some pharmacokinetic problems. Carbohydrates as most common organic molecules are an important issue of plant and animal metabolisms. They are non toxic and have important duties in the body like participating in DNA and RNA synthesis and being responsible for energy production. In addition, they have many hydroxyl, aldehyde and ketone groups that attract attention for synthesis as a potential drug derivative. 1,2,3,-Triazole compounds have also important role in heterocyclic chemistry because of their pharmaceutical properties and their high reactivity, which could be used as a building block for complex chemical compounds. In this study, following the "Click Reaction" of 5-FU and tetra- O -acetylglycose the 5-fluorouracil derivative 1-[{1'-(2″,3″,4″,6″-tetra- O -acetyl- β -d-glycopyronosyl)-1' H -1',2',3'-triazole-4'-yl} methyl]5-fluorouracil was synthesized. Following, a micellar formulation of 5-Fluorouracil derivative was prepared and characterized in terms of particle size, polydispersity index, zeta potential, refractive index and pH. Furthermore, the cytotoxicity and mutagenicity of the 5-fluorouracil derivative was investigated using an in vitro cell culture model and the AMES test. According to the results of this study, the novel 5-fluorouracil derivative could be a drug candidate for the therapy of cancer and needs further in vivo investigations.

Hydrogen bonding and π-π interactions take special part in the enantioselectivity task. In this regard, because of having both hydrogen acceptor and hydrogen donor groups, melamine derivatives become more of an issue for enantioselectivity. In the light of such information, triazine-based chiral, fluorescence active novel thiazole derivatives L1 and L2 were designed and synthesized from (S)-(-)-2-amino-1-butanol and (1S,2R)-(+)-2-amino-1,2-diphenylethanol. The structural establishment of these compounds was made by spectroscopic methods such as FTIR, 1 H, and 13 C NMR. While the solution of these compounds in DMSO did not show any fluorescence emission, it was observed that the emission increased 44-fold for L1 and 55-fold for L2 in 95% water, similar to the aggregation-induced emission (AIE) characterized compounds. In this regard, enantioselective capabilities of these compounds against carboxylic acids were tested, and in experiments carried out at a ratio of 40/60 DMSO/H 2 O, it was determined that R-2ClMA increased the fluorescence emission of L1 chiral receptor by 2.59 times compared to S-isomer., (© 2017 Wiley Periodicals, Inc.)

With the aim to create a library of compounds with potential bioactivities by combining special characteristics of two important groups such as nucleobases and carbohydrates, twenty 1,4-disubstituted-triazole nucleosides were synthesized in good yields (80-94%) using the copper catalyzed 'Click' reaction between azido-modified pento- or hexopyranoses and alkyne-bearing pyrimidine or purine nucleobases. Structural elucidation was made with the assistance of spectroscopic techniques such as FTIR, 1D-, 2D-NMR, and ESI-TOFMS. All the synthesized triazole nucleosides were evaluated for their cytotoxic activity against three human cancer cell lines (MDA-MB-231, Hep3B, PC-3) by using the MTT assay. Particularly, compounds 3a and 1b were identified as potential hits against Hep3B cell.

Oval cells proliferate extensively in the livers of animals exposed to oncogenic insults, are bipotent and are believed to be related to the so far unidentified liver stem cell. In normal liver, cells antigenically related to oval cells and expressing liver and epithelial markers are considered to be liver progenitor cells. We isolated, by fluorescence-activated cell sorting or magnetic bead sorting, cells expressing the oval cell antigens OC.2 or OC.3 from the liver of normal newborn or day 12 embryonal age rats. Magnetic bead sorting of positive cells was as efficient as fluorescence-activated cell sorting. A two-chamber culture system was devised in which cells were plated onto transwell filters coated with type IV collagen and cultured in a serum-free Ham's F12 medium supplemented with free fatty acids and bovine serum albumin. Under these conditions, cells remained viable for up to 6 weeks and their antigenic phenotype was unchanged throughout. Approximately 30% of sorted cells expressed epithelial and/or liver-specific markers. Growth factors mitogenic for epithelial cells and hepatocytes did not elicit cell proliferation. These results provide an important background for further studies designed to determine the biological significance of OC.2+ and OC.3+ cells in normal liver, to test the liver stem cell hypothesis and to develop protocols for the expansion in vitro of normal liver progenitors.

The crystal structure of the transcription factor IIB (TFIIB)/TATA box-binding protein (TBP)/TATA-element ternary complex is described at 2.7 A resolution. Core TFIIB resembles cyclin A, and recognizes the preformed TBP-DNA complex through protein-protein and protein-DNA interactions. The amino-terminal domain of core TFIIB forms the downstream surface of the ternary complex, where it could fix the transcription start site. The remaining surfaces of TBP and the TFIIB can interact with TBP-associated factors, other class II initiation factors, and transcriptional activators and coactivators.

Oval cells, a non-parenchymal cell population induced to rapidly proliferate in animals treated with carcinogens, are thought to be related to the hypothesized liver stem cells. In normal liver there are poorly defined cells antigenically related to oval cells. These oval cell antigen positive (OCAP) cells present in normal animals are thought to include hepatocyte and bile duct cell precursors. To isolate them, we modified the existing protocols designed for oval cells and used it on normal neonatal rat livers. Using flow cytometry, the percentage of normal liver OCAP-cells varied with the monoclonal antibody (MoAb) to the different oval cell membrane markers used: 12% (MoAb 18.2), 23% (MoAb 270.38), 27% (MoAb 18.11), 31% (MoAb 18.13), and 37% (MoAb 374.3). Macrophages consisted 10% of the cells (MoAb MCA 275); hepatocytes were essentially absent ( < 1%, MoAb 236.4). Our results demonstrate that is possible to obtain significant numbers of normal cells antigenically related to oval cells and that using different MoAbs, different cell populations can be sorted for use in experimental studies testing liver progenitor cell hypothesis.

The three-dimensional structure of an HNF-3/fork head DNA-recognition motif complexed with DNA has been determined by X-ray crystallography at 2.5 A resolution. This alpha/beta protein binds B-DNA as a monomer, through interactions with the DNA backbone and through both direct and water-mediated major and minor groove base contacts, inducing a 13 degrees bend. The transcription factor fold is very similar to the structure of histone H5. In its amino-terminal half, three alpha-helices adopt a compact structure that presents the third helix to the major groove. The remainder of the protein includes a twisted, antiparallel beta-structure and random coil that interacts with the minor groove.

Variants that no longer express an entire H-2 haplotype were readily isolated, by immunoselection with antisera directed against the haplotype, from an H-2b/H-2d heterozygous Friend leukemia cell line carrying a Robertsonian translocation of the chromosomes bearing the H-2 genetic region. These variants can be denoted as being of the phenotype H-2b- H-2d+ or H-2b+ H-2d-. Some of the H-2b- H-2d+ variants: (1) lack the restriction enzyme fragments characteristic of the missing H-2b haplotype, as assessed by Southern blot analysis; (2) express more cell surface H-2d antigens than wild-type cells, as assessed by flow microfluorimetry; and (3) appear to have become homozygous for the more active H-2d-linked allele at the Glyoxalase I locus. These variants thus seem to have lost genetic material corresponding to the H-2b haplotype and may have gained genetic material corresponding to the H-2d haplotype. These results are consistent with the possibility that these variants were generated by mitotic recombination.