20 research outputs found

    A First Glimpse of Wild Lupin Karyotype Variation As Revealed by Comparative Cytogenetic Mapping

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    Insight into plant genomes at the cytomolecular level provides useful information about their karyotype structure, enabling inferences about taxonomic relationships and evolutionary origins. The Old World lupins (OWL) demonstrate a high level of genomic diversification involving variation in chromosome numbers (2n = 32-52), basic chromosome numbers (x = 5-7, 9, 13) and in nuclear genome size (2C DNA = 0.97-2.68 pg). Lupins comprise both crop and wild species and provide an intriguing system to study karyotype evolution. In order to investigate lupin chromosome structure, heterologous FISH was used. Sixteen BACs that had been generated as chromosome markers for the reference species, Lupinus angustifolius, were used to identify chromosomes in the wild species and explore karyotype variation. While all “single-locus” in L. angustifolius, in the wild lupins these clones proved to be “single-locus,” “single-locus” with additional signals, “repetitive” or had no detectable BAC-FISH signal. The diverse distribution of the clones in the targeted genomes suggests a complex evolution history, which possibly involved multiple chromosomal changes such as fusions/fissions and repetitive sequence amplification. Twelve BACs were sequenced and we found numerous transposable elements including DNA transposons as well as LTR and non-LTR retrotransposons with varying quantity and composition among the different lupin species. However, at this preliminary stage, no correlation was observed between the pattern of BAC-FISH signals and the repeat content in particular BACs. Here, we describe the first BAC-based chromosome-specific markers for the wild species: L. cosentinii, L. cryptanthus, L. pilosus, L. micranthus and one New World lupin, L. multiflorus. These BACs could constitute the basis for an assignment of the chromosomal and genetic maps of other lupins, e.g., L. albus and L. luteus. Moreover, we identified karyotype variation that helps illustrate the relationships between the lupins and the extensive cytological diversity within this group. In this study we premise that lupin genomes underwent at least two rounds of fusion and fission events resulting in the reduction in chromosome number from 2n = 52 through 2n = 40 to 2n = 32, followed by chromosome number increment to 2n = 42

    Genetic technology transfer to Kenyan agriculture in the context of biotechnology research

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    Genetic Technology Transfer to Kenyan Agriculture in the Context of Biotechnology Research

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    Technology development is a crucial issue for economic development in Sub-Saharan African countries. In this paper current research on biotechnology and the potential of biotechnology absorption in Kenya is analyzed. The institutional character, areas of research and funding mechanisms of the research institutions contributing to agriculture sector technological advancements were examined in the context of local farmer’s needs. Also factors, such as legal framework and cultural and social values for the biotechnology research in the region were explored. Literature review and the qualitative analysis of data on research facilities and the papers from the region were applied in the research. OLS correlation method was applied in the analysis of the data

    Fabrication of Gelatin-ZnO Nanofibers for Antibacterial Applications

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    In this study, GNF@ZnO composites (gelatin nanofibers (GNF) with zinc oxide (ZnO) nanoparticles (NPs)) as a novel antibacterial agent were obtained using a wet chemistry approach. The physicochemical characterization of ZnO nanoparticles (NPs) and GNF@ZnO composites, as well as the evaluation of their antibacterial activity toward Gram-positive (Staphyloccocus aureus and Bacillus pumilus) and Gram-negative (Escherichia coli and Pseudomonas fluorescens) bacteria were performed. ZnO NPs were synthesized using a facile sol-gel approach. Gelatin nanofibers (GNF) were obtained by an electrospinning technique. GNF@ZnO composites were obtained by adding previously produced GNF into a Zn2+ methanol solution during ZnO NPs synthesis. Crystal structure, phase, and elemental compositions, morphology, as well as photoluminescent properties of pristine ZnO NPs, pristine GNF, and GNF@ZnO composites were characterized using powder X-ray diffraction (XRD), FTIR analysis, transmission and scanning electron microscopies (TEM/SEM), and photoluminescence spectroscopy. SEM, EDX, as well as FTIR analyses, confirmed the adsorption of ZnO NPs on the GNF surface. The pristine ZnO NPs were highly crystalline and monodispersed with a size of approximately 7 nm and had a high surface area (83 m2/g). The thickness of the pristine gelatin nanofiber was around 1 µm. The antibacterial properties of GNF@ZnO composites were investigated by a disk diffusion assay on agar plates. Results show that both pristine ZnO NPs and their GNF-based composites have the strongest antibacterial properties against Pseudomonas fluorescence and Staphylococcus aureus, with the zone of inhibition above 10 mm. Right behind them is Escherichia coli with slightly less inhibition of bacterial growth. These properties of GNF@ZnO composites suggest their suitability for a range of antimicrobial uses, such as in the food industry or in biomedical applications

    Cellular uptake and retention studies of silica nanoparticles utilizing senescent fibroblasts

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    Abstract Understanding the interplay between nanoparticles (NPs) and cells is essential to designing more efficient nanomedicines. Previous research has shown the role of the cell cycle having impact on the efficiency of cellular uptake and accumulation of NPs. However, there is a limited investigation into the biological fate of NPs in cells that are permanently withdrawn from the cell cycle. Here we utilize senescent WI-38 fibroblasts, which do not divide and provide a definitive model for tracking the biological fate of silica nanoparticles (SiNPs) independent of cell cycle. We use several methods to measure the cellular uptake kinetics and intracellular retention of SiNPs, including confocal laser scanning microscopy (CLSM), flow cytometry, and transmission electron microscopy (TEM). We demonstrate that SiNPs readily enter into senescent cells. Once internalized, SiNPs do not exit and accumulate in the cytoplasm for long term. Our study provides a basis for future development of NP-based tools that can detect and target senescent cells for therapy

    Facile Synthesis of Sulfobetaine-Stabilized Cu<sub>2</sub>O Nanoparticles and Their Biomedical Potential

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    A novel approach using a zwitterionic sulfobetaine-based surfactant for the synthesis of spherical copper oxide nanoparticles (Cu<sub>2</sub>O NPs) has been applied. For the first time, N-hexadecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate has been used as stabilizer to control the size and morphology of Cu<sub>2</sub>O NPs. Several techniques, such as transmission electron microscopy (TEM), X-ray diffraction (XRD), and fluorescence spectroscopy, are used to investigate the size, structure, and optical properties of synthesized Cu<sub>2</sub>O nanocrystals. The results indicate that copper­(I) oxide nanoparticles with size in the range of 2 to 45 nm and crystalline structure, exhibit intense yellow fluorescence (λ<sub>em</sub> = 575 nm). Furthermore, the cytotoxicity studies show that sulfobetaine-stabilized copper oxide nanoparticles prompt inhibition of cancer cell proliferation in a concentration-dependent manner, however, the adverse effect on the normal cells has also been observed. The results indicate that the sulfobetaine-stabilized Cu<sub>2</sub>O, because of their unique properties, have a potential to be applied in medical fields, such as cancer therapy and bioimaging
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