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Transplacental Cocaine Exposure: Behavioral Consequences
Published in Richard J. Konkol, George D. Olsen, Prenatal Cocaine Exposure, 2020
Aaron S. Wilkins, Barry E. Kosofsky, Anthony G. Romano, John A. Harvey
There are several different forms of attention, including selective attention, divided attention, and sustained attention, which includes vigilance.39 Deficits in mechanisms underlying these forms of attention may result in specific impairments in performance in humans and rodents. In normal humans, treatment with IV clonidine, a noradrenergic alpha2 agonist, impairs attentional performance.40–43 In rats, Robbins and colleagues found that performance in tasks requiring attention can be disrupted by lesioning the dorsal noradrenergic bundle (DNAB).44,45 In a visual discrimination task (5-choice serial reaction time task), rats were required to detect brief visual stimuli presented unpredictably at one of five locations and then push a panel paired with the stimulus. Animals with the DNAB lesions displayed deficits in attention in this task when a) loud bursts of white noise were interpolated immediately prior to each visual stimulus,44 b) the stimuli were presented unpredictably in time,46 and c) the rats were treated with amphetamine, which caused impulsive and premature responding.47 Thus the noradrenergic system is believed to be involved in attentional processing.39,46,48,49 Yet researchers have found that lesions of the dopaminergic,48 serotonergic,50 or cholinergic51 systems also disrupt attention. According to Robbins and Everitt,49 these systems probably interact in modulating attention.
Conformational Changes in Nucleic Acids Modified by Chemical Carcinogens
Published in Philip L. Grover, Chemical Carcinogens and DNA, 2019
D. Grunberger, I. B. Weinstein
In a DNA helix with Watson-Crick geometry (DNA-B), all of the nucleoside residues are in the anti conformation and the deoxyribose residues have the C2′endo structure. The anti conformation is essential for base pairing between the complementary strands in the helix and it also appears to be essential for Watson-Crick-type base pairing during nucleic acid replication, transcription, and codon-anticodon recognition. Stabilization of the helix structure involves base-pairing and base-stacking energies, as well as the short-range intramolecular interactions associated with the polynucleotide backbone.4
B cells require licensing by dendritic cells to serve as primary antigen-presenting cells for plasmid DNA
Published in OncoImmunology, 2023
Ichwaku Rastogi, Douglas G. McNeel
Because we did not detect CD8 T-cell activation, despite B cell activation, we next evaluated the purity of B cells obtained after either negative selection (as used in this manuscript) or after enrichment using PE positive selection (as in our previous manuscript). We achieved higher purity of B cells using negative selection (Supplemental Figure 1a), suggesting that contaminating cells might affect B cell uptake and/or antigen presentation. Consequently, we next evaluated whether the antigen encoded by DNA was translated in different APC subsets. We cultured B cells and DCs, either individually or together, with DNA encoding GFP. As shown in Figure 1b, we identified B cells that expressed GFP, but exclusively in the group where B cells and DCs were in co-culture. On the contrary, DCs did not express GFP, either when cultured alone or with B cells. We were unable to confirm the GFP expression in B cells via conventional flow cytometry or via western blotting. This can be attributed to the low number of B cells that express GFP which would be below the detection threshold of these assays. Collectively, our results indicated that upon passive uptake of plasmid DNA, B cells were the only subset of professional APCs that would transcribe and translate the encoded antigen. However, for translation of the encoded antigen, B cells required co-culture with DCs.
DNA binding, BSA interaction and in-vitro antimicrobial studies of Cu(II), Co(III), Ni(II) and VO(IV) complexes with a new Schiff base
Published in Egyptian Journal of Basic and Applied Sciences, 2020
Disha Sharma, Hosakere D. Revanasiddappa, Basavegowda Jayalakshmi
In the above equation, concentration of DNA base pairs denotes [DNA], εa is the extinction coefficient (Aobs/[MC]) of the complex at a given DNA concentration εb and ɛf correspond to the extinction coefficient of free and the fully bound to DNA, respectively. A plot of [DNA]/b(b, which is a ratio of the slope to the intercept. The calculated intrinsic binding constants (Kb) of all complexes were found to be 4.26 × 105, 6.33 × 106, 3.89 × 105, 6.57 × 106, 4.52 × 105, 5.93 × 106, 4.79 × 105 and 6.67 × 106 M−1 for complexes C1-C8, respectively. These values are almost always after with classified intercalators (Ethidium bromide), whose binding constants are in the range of 106–107 M−1, suggests that the complexes have intercalative binding mode, which involves a stacking mode of interaction between these complexes and DNA base pairs. The spectral results reveals that intercalative interaction between DNA and the complex shows significant hyperchromism and the red shift is responsible for ᴨ-ᴨ* transition between them. The intensity of absorption band is decreases with the increasing DNA concentrations.
In vitro and in vivo efficacy of Caenorhabditis elegans recombinant antimicrobial protein against Gram-negative bacteria
Published in Biofouling, 2019
Dilawar Ahmad Mir, Krishnaswamy Balamurugan
The antibacterial mode of action of ABF-1 in the S. Typhi strain was further investigated. After confirming the growth inhibition effect of ABF-1 on the selected strains, proteomic analysis indicated intrinsic DNA damage, which might presumably be due to the frequent oxidative lesions caused by ABF-1 proteins. DNA repair is a frequent event in the bacterial life cycle (Michel et al. 2004; Kreuzer 2005). The downregulated proteins (RuvB helicase, RecA, mukF, endonuclease VIII, rpoC, yajQ, cspA, greA, t1627, dnaB and rcsB) play an important role in DNA repair, recombination, the SOS response, the formation of chromosome dimmers, and binding of damaged DNA (Borukhov et al. 1992; Iype et al. 1994; Yamazoe et al. 1999; Bae et al. 2000; Skunca et al. 2013). The proteomic results indicate potential intrinsic changes in the biosynthesis of bacterial lipids and fatty acids after ABF-1 treatment. The various downregulated proteins in this study are outer membrane lipoprotein carrier protein (lolA), synthesis of lipid (lpxH), and fatty acid oxidation (fadA). The integral membrane protein (FtsH) plays a quality control role (Katz and Ron 2008). The mdoG and glgC proteins were downregulated. These are known to have an important role in the biosynthesis of periplasmic glucans (Cifuente et al. 2016). Downregulated mdoG proteins reduce the motility in hypo-osmotic growth conditions, which has shown attenuated virulence in mice (Bhagwat et al. 2009). Glycans are saccharides that can be attached to a large range of biological molecules through an enzymatic process, glycosylation, and are important in proper protein folding and cell-to-cell interactions. Glucan biosynthesis protein (mdoG) is involved in the biosynthesis of osmoregulated periplasmic glucans (OPGs), and downregulated mdoG reduces the glycosylation process - the ipxH protein mediated the formation of UDP-N-acetyl-D-glucosaminuronic acid from UDP-N-acetyl-D-glucosamine, which is an initial step in O-antigen biosynthesis (Miller et al. 2004).