A combination of Murashige and Skoog's medium and N 6 -benzyladenine (BA) at various concentrations (0, 0.1, 0.25, 0.5, 0.75, 1.0, 1.25 and 1.5 mg l )1 ) was supplied to shoot tips from root cuttings of a 50-yearold wild-cherry tree (Prunus avium). The concentration of BA in the growing medium was a determining factor with respect to the number of proliferated shoots per explant in vitro. Normal and fasciated shoots were generated when BA was present at 0.5, 0.75, 1.0 and 1.25 mg l )1 in the medium and the mean numbers of normal shoots per explant were 3.63, 5.37, 8.93 and 7.30 respectively, and those of the fasciated shoots per explant were 0.03, 0.1, 0.47 and 0.4 respectively. Anatomical analysis by confocal microscopy of sections of paraffin-embedded specimens revealed that the cell structure and organization of the cortex and vascular cylinder in the fasciated shoots was similar to that in normal shoots. However, the cross-sectional area of stem of the fasciations was apparently greater than that of the normal shoots. In particular, the volume of vascular tissues, of pith and of some individual parenchyma cells in the cortex and pith was apparently greater in fasciated shoots than in normal shoots. Increases in cytokinesis and morphogenetic activity, such as the development of callus-like regions and the formation of adventitious shoots, were observed in the cortex and pith throughout the fasciations. The fasciated shoots had numerous buds and initiating new shoots at their apices while normal shoots had a single dominant axial bud.

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Fasciation (or cristation) is a variation in the morphology of plants, characterized by the development of various widened and flattened organs. According to origin, fasciations are classified as physiological or genetic but comparatively little is known on their epigenetic or genetic nature at the molecular level. Physiological fasciations are caused by natural environmental factors or artificial treatments including exogenously applied growth regulators. CLAVATA genes (CLV1, CLV2, and CLV3) have been shown to be the main genetic factors associated with fasciation. Despite the great variety of fasciation-induction factors, fasciations have similar features of development during the first few weeks, i.e., increased mitotic activity and size of the apical meristem and an altered arrangement of cells in the meristematic zones, often leading to an increased number of organs and changes in the plastochron. The enhanced activity of apical meristem and cambium results in a significantly increased circumference of the stem and enlarged proportions of pith and cortical parenchyma, associated with a delayed differentiation of the vascular tissues. An elliptical or irregular shape of the cross section of a fasciated organ corresponds to a similar shape of the vascular cylinder. Later stages of the ontogenic development of fasciations are species-specific, may depend on the origin of fasciation, and in some cases may lead to deviations from the normal structure of the epidermis, shape of leaves, as well as altered development of axillary buds. Studying the causes and patterns of development of fasciations could provide a better understanding of the growth processes in the vegetative apex. Further anatomical and physiological research should focus on the structure and activity of meristems of fasciated shoots, as well as on their transcriptome analysis, in order to better understand the pattern of fasciation development.

Hemocyanins are oxygen-transporting glycoproteins in the hemolymph of arthropods and mollusks that attract scientific interest with their diverse biological activities and potential applications in pharmacy and medicine. The aim of the present study was to assess the in vitro antitumor activity of hemocyanins isolated from marine snail Rapana venosa (RvH) and garden snails Helix lucorum (HlH) and Helix aspersa (HaH), as well the mucus of H. aspersa snails, in the HT-29 human colorectal carcinoma cell line. The effects of the hemocyanins on the cell viability and proliferation were analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and the alterations in the tumor cell morphology were examined by fluorescent and transmission electron microscopy. The results of the MTT assay showed that the mucus and α-subunit of hemocyanin from the snail H. aspersa had the most significant antiproliferative activity of the tested samples. Cytomorphological analysis revealed that the observed antitumor effects were associated with induction of apoptosis in the tumor cells. The presented data indicate that hemocyanins and mucus from H. aspersa have an antineoplastic activity and potential for development of novel therapeutics for treatment of colorectal carcinoma.

(1) Background: (KLAKLAK)2 is a representative of the antimicrobial peptide group which also shows good anticancer properties. (2) Methods: Herein, we report synthesis using SPPS and characterization by HPLC/MS of a series of shortened analogues of (KLAKLAK)2. They contain single sequence KLAKLAK as C-terminal amides. In addition, substitution of some natural amino acids with unnatural β-Ala and nor-Leu is realized. In addition, these structures are conjugated with second pharmacophore with well proven anticancer properties 1,8-naphthalimide or caffeic acid. Cytotoxicity, antiproliferative effect and antimicrobial activity of newly synthesized structures were studied. (3) Results: The obtained experimental results reveal significant selective index for substances with common chemical structure KLβAKLβAK-NH2. The antibacterial properties of newly synthesized analogues at two different concentrations 10 μM and 20 μM, were tested against Gram-negative microorganisms Escherichia coli K12 407. Only two of the studied compounds KLAKLAK-NH2 and the one conjugated with second pharmacophore 1,8-naphthalimide and unnatural amino acid nor-Leu showed moderate activity against tested strains at concentration of 20 μM. (4) Conclusions: The obtained results reveal that the introducing of 1,8-naphthalimideGly- and Caf- increase the cytotoxicity and antiproliferative activity of the peptides but not their selectivity. Only two compounds KLAKLAK-NH2 and 1,8-naphthalimideGKnLAKnLAK-NH2 show moderate activity against Escherichia coli K12 at low concentration of 20 μM.