Does the platelet-activating factor affect the antioxidant defense system?

The platelet-activating factor (PAF) is an inflammatory mediator and it may exert some of its effects by reactive oxygen species (ROS). We investigated the effects of PAF and hyperbaric oxygenation (HBO) on copper (Cu) and zinc (Zn) levels in plasma and the intracellular antioxidant enzyme activities of rats. PAF administration caused a decrease in erythrocyte catalase (CAT) and glutathione peroxidase (GPx) activities and in the plasma zinc level. Following PAF administration, exposure to HBO also caused a decrease in erythrocyte GPx activity. These results support the hypothesis that PAF may produce free oxygen radicals and HBO enhances this effect. The enzyme activities of the antioxidant defense system were found to be affected by these oxidative processes. This is likely to be the result of excessive production of ROS or overutilization and/or inhibition of the antioxidant enzymes.     

Antioxidative metabolism in down syndrome

Down syndrome is the most common cause of mental retardation, affecting 1 in 700–800 liveborn infants. Although numerous biochemical abnormalities accompanying the syndrome have not yet been completely clarified, the antioxidant defense system enzymes have shown to be altered due to increased gene dosage on chromosome 21 and overproduction of superoxide dismutase (SOD-1 or Cu/Zn SOD). The purpose of this study was to investigate the activities of SOD-1 and glutathione peroxidase (GSH-Px) enzymes and the levels of their cofactors zinc (Zn), copper (Cu) and selenium (Se) in plasma of 20 Down syndrome patients. In comparison with age and sex-matched controls (n=15), plasma GSH-Px, SOD, and Cu levels were significantly decreased in the patient group, but Zn and Se concentrations remained unchanged. This study was presented as a poster in 29th Annual Meeting of European Society of Human Genetics held in Genoa in May, 1997.     

Polyaniline grafted polyacylonitrile conductive composite fibers for reversible immobilization of enzymes: Stability and catalytic properties of invertase

Polyacylonitrile fibers (PAN) surfaces were modified with chemical polymerization of conductive polyaniline (PANI) in the presence of potassium dichromate as an oxidizing agent. The effect of aniline concentration on the grafting efficiency and on the electrical surface resistance of PAN/PANI composite fibers was investigated. The surface resistance of the conductive composite fibers in this work was found to be between 8.0 and 0.5 kΩ/cm. As the amount of grafted PANI increased on the PAN fibers the electrical resistance of composite fibers decreased. The PAN/PANI composite fibers were characterized by SEM and FTIR studies. Composite PAN/PANI fibers were used for reversible immobilization of invertase. The immobilization efficiency and the activity of the immobilized invertase (from 1.0 mg/mL invertase solution at pH 5.5) were increased with increasing PANI contents of the composite fibers. The maximum amount of immobilized enzyme onto composite fibers containing 2.0% PANI was about 76.6 mg/g. The optimum pH for the free enzyme was observed at 5.0. On the other hand, immobilized invertase yielded a broad optimum pH profile between pH 5.0 and 7.0. Immobilized invertase exhibited 83% of its original activity even after two months storage at 4 °C while the free enzyme showed only 7% of its initial activity.     

A New Organic Dye-Based Staining for The Detection of Plant DNA in Agarose Gels

Ethidium bromide (EtBr) is used to stain DNA in agarose gel electrophoresis, but this dye is mutagenic and carcinogenic. We investigated N-719, which is a visible, reliable and organic Ruthenium-based dye, and five fluorescent alternatives for staining plant DNA. For prestaining and poststaining, N-719, GelRed, and SYBR Safe stained both DNA and PCR product bands as clearly as EtBr. SYBR Green I, methylene blue, and crystal violet were effective for poststaining only. The organic dye N-719 stained DNA bands as sensitively and as clearly as EtBr. Consequently, organic dyes can be used as alternatives to EtBr in plant biotechnology studies.     

Nisin production of Lactococcus lactis N8 with hemin‐stimulated cell respiration in fed‐batch fermentation system

In this study, nisin production of Lactococcus lactis N8 was optimized by independent variables of glucose, hemin and oxygen concentrations in fed‐batch fermentation in which respiration of cells was stimulated with hemin. Response surface model was able to explain the changes of the nisin production of L. lactis N8 in fed‐batch fermentation system with high fidelity (R² 98%) and insignificant lack of fit. Accordingly, the equation developed indicated the optimum parameters for glucose, hemin, and dissolved oxygen were 8 g L^?1 h^?1, 3 μg mL^?1 and 40%, respectively. While 1711 IU mL^?1 nisin was produced by L. lactis N8 in control fed‐batch fermentation, 5410 IU mL^?1 nisin production was achieved within the relevant optimum parameters where the respiration of cell was stimulated with hemin. Accordingly, nisin production was enhanced 3.1 fold in fed‐batch fermentation using hemin. In conclusion the nisin production of L. lactis N8 was enhanced extensively as a result of increasing the biomass by stimulating the cell respiration with adding the hemin in the fed‐batch fermentation. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:678–685, 2015     

Mutations in CSPP1 Cause Primary Cilia Abnormalities and Joubert Syndrome with or without Jeune Asphyxiating Thoracic Dystrophy

Joubert syndrome (JBTS) is a recessive ciliopathy in which a subset of affected individuals also have the skeletal dysplasia Jeune asphyxiating thoracic dystrophy (JATD). Here, we have identified biallelic truncating CSPP1 (centrosome and spindle pole associated protein 1) mutations in 19 JBTS-affected individuals, four of whom also have features of JATD. CSPP1 mutations explain ∼5% of JBTS in our cohort, and despite truncating mutations in all affected individuals, the range of phenotypic severity is broad. Morpholino knockdown of cspp1 in zebrafish caused phenotypes reported in other zebrafish models of JBTS (curved body shape, pronephric cysts, and cerebellar abnormalities) and reduced ciliary localization of Arl13b, further supporting loss of CSPP1 function as a cause of JBTS. Fibroblasts from affected individuals with CSPP1 mutations showed reduced numbers of primary cilia and/or short primary cilia, as well as reduced axonemal localization of ciliary proteins ARL13B and adenylyl cyclase III. In summary, CSPP1 mutations are a major cause of the Joubert-Jeune phenotype in humans; however, the mechanism by which these mutations lead to both JBTS and JATD remains unknown.     

Growth and fluctuating asymmetry of human newborns: Influence of inbreeding and parental education

Historically, medical concerns about the deleterious effects of closely inbred marriages have focused on the risk posed by recessive Mendelian disease, with much less attention to developmental instability. We studied the effects of inbreeding (first‐cousin marriage) on growth and fluctuating asymmetry of 200 full‐term infants (101 inbred and 99 outbred) whose parents were of similar socioeconomic status in Sivas Province, Turkey. In addition to differences in their mean inbreeding coefficients (f = 1/16 for first cousins and f < 1/1,024 for unrelated parents), the consanguineous parents were less well educated (3 years, on average for both husbands and wives). We measured weight, height, head circumference, and chest circumference of the newborns, as well as four bilateral traits (ear width, ear length, and second and fourth digit lengths). After taking education into account, none of the measures of size (weight, height, head circumference, and chest circumference) and fluctuating asymmetry differed between the inbred and outbred groups. Male children of well‐educated parents, however, were larger and had less fluctuating asymmetry. Female children of well‐educated parents weighed more than those of less well‐educated parents, but were otherwise indistinguishable for height, head circumference, chest circumference, and fluctuating asymmetry. We conclude that inbreeding depression causes neither an increase in fluctuating asymmetry of full‐term newborns, nor a decrease in body size. Unmeasured variables correlated with education appear to have an effect on fluctuating asymmetry and size of male children and only a weak effect on size (weight) of female children. Am J Phys Anthropol 153:45–51, 2014. © 2013 Wiley Periodicals, Inc.     

Antimicrobial activity of copper and silver nanofilms on nosocomial bacterial species

Contaminated surfaces are possible vehicles in infection transmission. It is known that both Copper (Cu) and Silver (Ag) efficiently inactivate microbes by direct contact. Aiming at using these metals for benefitting from their antimicrobial effect, but to avoid subsequent toxic effects, we evaluated the antimicrobial activity of nanometric thin Silver and Copper films covering less expensive materials. Using a modified version of the Japan Industrial Standard JIS Z 2801:2000, we demonstrated the antimicrobial activity of the surfaces covered with metal ions nanofilms on microorganisms possibly involved in nosocomial infections and on Bacillus anthracis, bacteria with possible implication in bioterrorist attacks. Copper covered surfaces proved to have better antimicrobial activity than Silver surfaces. Silver covered surfaces showed better activity on Gram negative bacteria than on Gram positive cocci. Going deeper with studies on antimicrobial effects using new methods with better direct and/or functional discriminatory capacity is needed in order to provide additional information on the mechanisms of Silver and Copper nanofilms antimicrobial activity.     

LINE-1 retrotransposition events affect endothelial proliferation and migration

Long interspersed nuclear element-1 (LINE-1, L1) is a retrotransposon which affects the human genome by a variety of mechanisms. While LINE-1 expression is suppressed in the most somatic human cells, LINE-1 elements are activated in human cancer. Recently, high accumulation of LINE-1-encoded ORF1p and ORF2p in endothelial cells of mature human blood vessels was described. Here, we demonstrate that LINE-1 de novo retrotransposition events lead to a reduction of endothelial cell proliferation and migration in a porcine aortic endothelial (PAE) cell model. Cell cycle studies show a G0/G1 arrest in PAE cells harboring LINE-1 de novo retrotransposition events. Remarkably, in in situ analysis LINE-1-encoded ORF2p was not detectable in tumor blood vessels of different human organs while vascular endothelial cells of corresponding normal organs strongly expressed LINE-1 ORF2p. Quantitative RT-PCR analysis revealed that LINE-1 de novo retrotransposition influences selectively the expression of some angiogenic factors such as VEGF and Tie-2. Thus, our data suggest that LINE-1 de novo retrotransposition events might suppress angiogenesis and tumor vascularisation by reducing the angiogenic capacity of vascular endothelial cells.