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Harnessing Indigenous Bioresources for Development of Diagnostics for Detection and Confirmation of Infectious Agents in Nigeria
Published in Hajiya Mairo Inuwa, Ifeoma Maureen Ezeonu, Charles Oluwaseun Adetunji, Emmanuel Olufemi Ekundayo, Abubakar Gidado, Abdulrazak B. Ibrahim, Benjamin Ewa Ubi, Medical Biotechnology, Biopharmaceutics, Forensic Science and Bioinformatics, 2022
E. O. Ekundayo, J. C. Igwe, Ifeoma M. Ezeonu
Dyes and stains remain important items of international trades. Nigeria like most of the developing countries import the dyes and stains needed for diagnostic applications. The stains commonly used include crystal violet, Safranin, neutral red, malachite green, Romanowsky stains like Giemsa, Field and Leishman stains. Large amounts of these reagents and stains are used in medical laboratories in hospitals and clinics and in laboratories in academic institutions. Local capability in their production is highly limited except for preparation of stain solutions from imported stain powders. Although the methods for the manufacture of the stain powders and dyes have been developed for over two centuries, Nigeria still imports dyes and stains to meet most of her needs.
Cytogenotoxic evaluations of leaves and stems extracts of Rubus rosifolius in primary metabolically noncompetent cells
Published in Journal of Toxicology and Environmental Health, Part A, 2023
Ana Paula Oliveira de Quadros, Isabel Bragança Baraldi, Marcel Petreanu, Rivaldo Niero, Mario Sergio Mantovani, Isabel O’Neill De Mascarenhas Gaivão, Edson Luis Maistro
The cells were suspended in methanol:acetic acid (5:1) and placed on slides using glass pipettes. After air drying for 24 hr, slides were stained in a solution of Giemsa dye (10%) in phosphate buffer (pH 6.8) for 5 min. For the analysis of the cells on the slides, a light microscope (Zeiss, Primo Star) was used, with 400× magnification, with the count of 1000 binucleated cells for treatment/repetition and controls, noting the presence of micronucleus (MN), nucleoplasmic bridges (NPBs), and nuclear buds (NBs) in the cells. An additional cytotoxicity measure was calculated using the cytokinesis-block proliferation index (CBPI), according to the following formula: [M1 + 2(M2) + 3(M3)/N], in which M1 = No. mononucleated cells, M2 = No. binucleated cells, M3 = No. multinucleated cells, and N = total cells analyzed (500 cells) to each treatment/repetition and controls (Fenech 2020; OECD, T. G 2016). The same protocol was used for both extracts. Two independent experiments were carried out.
Chromosomal damage in occupationally exposed health professionals assessed by two cytogenetic methods
Published in Archives of Environmental & Occupational Health, 2023
Dita Kadlcikova, Petra Musilova, Hana Hradska, Miluse Vozdova, Marketa Petrovova, Marek Svoboda, Jiri Rubes
Slides with chromosome spreads were stained with 5% Giemsa solution. Only well-spread metaphases containing 45–47 centromeres were assessed.3 The aberrations in peripheral lymphocytes were scored according to Carrano and Natarajan.4 One hundred metaphases per sample were analyzed to score the frequency of chromatid breaks and exchanges, chromosome breaks and exchanges, as well as the number of breaks per cell and the percentage of aberrant cells. A cell was considered aberrant if it carried at least one of the above-mentioned aberrations. In cases of chromatid breaks (chtb), chromatid exchanges (chte), chromosome breaks (chrb), chromosome exchanges (chre), each type of aberration was counted separately and expressed as a frequency of aberration type per 100 investigated cells. The number of breaks per cell (B/C) was calculated from chromatid and chromosome breaks and exchanges. A break represented one break, while an exchange two breaks; fragmentation and one to two acentric chromosomes in a cell with a dicentric chromosome were not counted into this parameter. Subsequently, a sum of breaks was divided by 100 investigated cells. The number of aberrant cells was a sum of all aberrant cells per 100 investigated cells, and thus frequency of aberrant cells (ab.c.). The mean and standard deviation and because data do not follow normal distribution, median and interquartile range are present in Table 2.
Protective effects and DNA repair induction of a coumarin-chalcone hybrid against genotoxicity induced by mutagens
Published in Journal of Toxicology and Environmental Health, Part A, 2022
Jefferson Hollanda Véras, Camila Regina Do Vale, Elisa Flávia Luiz Cardoso Bailão, Murilo Machado Dos Anjos, Clever Gomes Cardoso, Matheus Gabriel de Oliveira, José Realino de Paula, Guilherme Roberto de Oliveira, Carolina Ribeiro E Silva, Lee Chen-Chen
The MN test was performed according to Ledebur and Schmid (1973) with modifications described by Carneiro et al. (2016). Bone marrow cells were smeared on glass slides, air-dried, and fixed with absolute methanol (Vetec, Duque de Caxias, RJ, Brazil) at room temperature for 5 min. The smears were stained as follows with Giemsa (Newprov, Pinhais, PR, Brazil), dibasic sodium phosphate (Vetec, Duque de Caxias, RJ, Brazil), and monobasic sodium phosphate (Vetec, Duque de Caxias, RJ, Brazil). In this assay, 4,000 polychromatic erythrocytes (PCE) per animal were analyzed and 5 animals were examined for each dose. Thus, a total of 20,000 PCEs per dose was assessed to determine the frequency of MNPCEs using light microscopy (Olympus BH-2 10 × 100, Tokyo, Japan). Genotoxicity and antigenotoxicity were assessed by the frequency of MNPCEs, whereas cytotoxicity and anticytotoxicity were evaluated using the PCE and normochromatic erythrocytes (NCE) ratio (PCE/NCE).