Identification of structural DNA variations in human cell cultures after long-term passage

Random amplified polymorphic DNA (RAPD) analysis was adapted for genomic identification of cell cultures and evaluation of DNA stability in cells of different origin at different culture passages. DNA stability was observed in cultures after no more than 5 passages. Adipose-derived stromal cells demonstrated increased DNA instability. RAPD fragments from different cell lines after different number of passages were cloned and sequenced. The chromosomal localization of these fragments was identified and single-nucleotide variations in RAPD fragments isolated from cell lines after 8–12 passages were revealed. Some of them had permanent localization, while most variations demonstrated random distribution and can be considered as de novo mutations.     

Enhanced antibacterial potential in UBP43-deficient mice against Salmonella typhimurium infection by up-regulating type I IFN signaling

ISG15 is an IFN-inducible ubiquitin-like protein and its expression and conjugation to target proteins are dramatically induced upon viral or bacterial infection. We have generated a UBP43 knockout mouse model that is lacking an ISG15-specific isopeptidase to study the biological role of the protein ISGylation system. We report that UBP43-deficient mice are hypersensitive to LPS-induced lethality and that TIR domain-containing adapter inducing IFN-beta --> IFN regulatory factor 3 --> type I IFN is the major axis to induce protein ISGylation and UBP43 expression in macrophages upon LPS treatment. In ubp43(-/-) macrophages, upon LPS treatment we detected increased expression of IFN-stimulated genes, including genes for several cytokines and chemokines involved in the innate immune response. The ubp43(-/-) mice were able to restrict the growth of Salmonella typhimurium more efficiently than wild-type mice. These results clearly demonstrate two aspects of IFN-signaling, a beneficial effect against pathogens but a detriment to the body without strict control.     

Monoclonal antibodies to the antigens of human HeLa tumor cells

A panel of 6 hybridomas "XEJIMA" producing monoclonal antibodies specific to HeLa cells is prepared. Monoclonal antibodies do not bind to antigens of human diploid fibroblasts, human continuous B- and T-lymphocytes and animal cell lines. The specificity of monoclonal antibodies to cellular antigens of 5 HeLa-like cell lines and 6 human tumour cells lines, not contaminated with HeLa cells, is determined. Antibody containing ascitic fluid and culture media of hybridomas XEJIMA-3, -12, -13, and -22 significantly decrease the attachment of HeLa cells to the surface of culture flasks. Monoclonal antibodies XEJIMA-11, -12 and -13 block the multiplication of HeLa cells. The effect depends on serum concentration in the nutrient medium.     

Previously unclassified mutation of mtDNA m.3472T>C: Evidence of pathogenicity in Leber’s hereditary optic neuropathy

Leber’s hereditary optic neuropathy (LHON) refers to a group of mitochondrial diseases and is characterized by defects of the mitochondrial electron transport chain and decreased level of oxidative phosphorylation. The list of LHON primary mtDNA mutations is regularly updated. In this study, we describe the homoplasmic nucleotide substitution m.3472T>C in the MT-ND1 (NADH-ubiquinone oxidoreductase chain 1) gene and specific changes in cell metabolism in a patient with LHON and his asymptomatic sister. To confirm the presence of mutation-related mitochondrial dysfunction, respiration of skin fibroblasts and platelets from the patient and his sister was studied, as well as the mitochondrial potential and production of reactive oxygen species in the skin fibroblasts. In addition, based on characteristics of the toxic effect of paraquat, a new approach was developed for detecting the functional activity of complex I of the mitochondrial respiratory chain.     

Population parameters and exploitation rate of Sarotherodon galilaeus galilaeus (Cichlidae) in Lakes Doukon and Togbadji,Benin

Growth, mortality, recruitment and relative yield per recruit of Sarotherodon galilaeus galilaeus from Lakes Doukon and Togbadji were studied. Data on total length, total weight and sex were recorded on a monthly basis between January and December 2013 for S. g. galilaeus captured by local fishers. The estimated asymptotic lengths L_∞ were 26.2 and 23.6?cm for Lakes Doukon and Togbadji, respectively, while the growth rate K was 0.73 in Lake Doukon and 0.87 in Lake Togbadji. Estimates of fishing mortality, 0.27 and 0.47 y^?1 for Doukon and Togbadji, respectively, were low relative to natural mortality, 1.51 and 1.74 y^?1, respectively. Sizes at first sexual maturity were 12.8 and 13.2?cm for females and males, respectively, in Lake Doukon, and 11.5 and 12.4?cm for females and males, respectively, in Lake Togbadji. The size at first capture was estimated at 13.3 and 12.7?cm for Lakes Doukon and Togbadji, respectively, which, in the light of the size at maturity estimates, indicates that fish spawn at least once before capture. The current exploitation rates of 0.15 for Lake Doukon and 0.21 for Lake Togbadji suggest that their stocks of S. g. galilaeus are not overexploited in either lake.     

Histopathological biomarkers and genotoxicity in gill and liver tissues of Nile tilapia Oreochromis niloticus from a polluted part of the Nile River,Egypt

Fish health is affected by water pollution. Oreochromis niloticus collected during summer 2014 from El-Serw, a polluted site on the Nile River, were compared with fish from a reference site, El-Zamalek. Histopathological changes were detected in gill and liver tissue samples using light and electron microscopy. In addition, the degree of DNA damage was measured using the comet assay. To indicate the severity of water pollution at the two sites, physico-chemical properties and heavy metal concentrations were investigated. Gill damage, including lamellar cell hyperplasia and aneurysm, was observed in the fish samples from the polluted site. The livers of fish from the polluted area showed necrosis and an increase in melanomacrophage centres. Histochemical results confirmed a marked rise of gill mucopolysaccharides and a reduction of carbohydrate stored in hepatocytes. Electron microscopy revealed clear alterations in gill and liver tissue of fish from the polluted site. The comet assay showed highly significant DNA damage in tilapia collected from the polluted site, compared to those from the reference site. Histopathological biomarkers and the comet assay may therefore be sensitive indicators of exposure to mixtures of aquatic pollutants in Nile tilapia.     

Situation of mycotoxins in milk, dairy products and human milk in Egypt

Abstact  Milk and dairy products purchased at Egyptian markets and breast milk from lactating mothers in Cairo and Giza governorates were analyzed for some mycotoxins. Three of 15 cows’ milk samples were found positive for Afl. M₁ with mean value 6.3 ppb. Only one sample of dried milk was positive (5 ppb). Two of 10 hard cheese samples contained detectable levels of Afl. M₁ (3and 6 ppb), whereas one sample containing Afl. B₁ and G₁ (10 and 4 ppb resp.). For soft cheese one sample of 10 was positive for Afl. M₁ (0.5 ppb). Blue veined cheeses were free of Afl. M₁ and PR-toxins. For breast milk two of 10 samples were positive for Afl. M₁ (20%) with mean value 2.75 ppb, while 3 of 10 samples were positive for Ochratoxin A (30 %).     

The virulence and colicinogenicity of pathogenic Escherichia isolated from water and human beings

An analysis of virulence and colicinogenicity of 180 cultures of pathogenic Escherichia of different origin has shown that the expressed characters occurred in 40 +/- 49% of strains isolated from people and 28.7 +/- 5.1% of strains isolated from water. The dependence of the studied properties on serogroups of the agents is established. These characters are more often inherent in representatives of the dominating serogroups, which may be a reason of their selective advantage in circulation among people and in water.     

The proteinase activity in the cell nuclei of rats following exposure to gamma radiation and methylnitrosourea

Activity of nuclear proteinases in blood and liver cells of rats exposed to whole-body gamma-irradiation (10 Gy) has been comparatively studied by the capacity of splitting the casein substrate. Proteinase activity in nuclei of irradiated rat leukocytes was shown to increase by 2.5 times and to gradually decrease after 48 h reaching 150-160% as compared to the control. Two hours following a single injection of methyl nitrosourea the alteration in the activity of proteinases in nuclei of rat hepatocytes and leukocytes was different from the alteration of this index after gamma-irradiation.     

Quantitative indices of the activity and the electrophoretic characteristics of staphylococcal catalase]

The average levels of activity of intracellular and extracellular catalase were determined. The activity of intracellular catalase was shown to be significantly higher than that of extracellular catalase, the average level of activity of extracellular catalase being higher in S. aureus than in S. epidermidis. In most of the strains one zone of extracellular catalase and two molecular forms of intracellular catalase were revealed by means of polyacrylamide gel electrophoresis.