16 research outputs found
Perinatal and Socioeconomic Risk Factors for Variable and Persistent Cognitive Delay at 24 and 48Ā Months of Age in a National Sample
The objective of this paper is to examine patterns of cognitive delay at 24 and 48 months and quantify the effects of perinatal and sociodemographic risk factors on persistent and variable cognitive delay. Using data from 7,200 children in the Early Childhood Longitudinal Study, Birth Cohort (ECLS-B), multiple logistic regression models identified significant predictors of low cognitive functioning at 24 and 48Ā months. Additional multiple logistic models predicting cognitive delay at 48Ā months were estimated separately for children with and without delay at 24Ā months. Of the nearly 1,000 children delayed at 24Ā months, 24.2% remained delayed by 48Ā months; 7.9% of the children not delayed at 24Ā months exhibited delay at 48Ā months. Low and very low birthweight increased cognitive delay risk at 24, but not 48Ā months. Low maternal education had a strongly increasing effect (ORĀ =Ā 2.3 at 24Ā months, ORĀ =Ā 13.7 at 48Ā months), as did low family income (ORĀ =Ā 1.4 at 24Ā months, ORĀ =Ā 7.0 at 48Ā months). Among children delayed at 24Ā months, low maternal education predicted delay even more strongly at 48Ā months (ORĀ =Ā 30.5). Low cognitive functioning is highly dynamic from 24 to 48Ā months. Although gestational factors including low birthweight increase childrenās risk of cognitive delay at 24Ā months, low maternal education and family income are more prevalent in the pediatric population and are much stronger predictors of both persistent and emerging delay between ages 24 and 48Ā months
New design of a lentiviral shRNA vector with inducible co-expression of ARGONAUTE 2 for enhancing gene silencing efficiency
Background: RNA interference (RNAi) is a robust tool for inhibiting specific gene expression, but it is limited by the uncertain efficiency of siRNA or shRNA constructs. It has been shown that the overexpression of ARGONAUTE 2 (AGO2) protein increases silencing efficiency. However, the key elements required for AGO2-mediated enhancement of gene silencing in lentiviral vector has not been well studied.Results: To explore the application of AGO2-based shRNA system in mammalian cells, we designed shRNA vectors targeting the EGFP reporter gene and evaluated the effects of various factors on silencing efficiency including stem length, loop sequence, antisense location as well as the ratio between AGO2 and shRNA. We found that 19 ~ 21-bp stem and 6- or 9-nt loop structure in the sense-loop-antisense (S-L-AS) orientation was an optimal design in the AGO2-shRNA system. Then, we constructed a single lentiviral vector co-expressing shRNA and AGO2 and demonstrated that the simultaneous expression of shRNA and AGO2 can achieve robust silencing of exogenous DsRed2 and endogenous ID1 and P65 genes. However, the titers of packaged lentivirus from constitutive expression of AGO2 vector were extremely low, severely limiting its broad application. For the first time, we demonstrated that the problem can be significantly improved by using the inducible expression of AGO2 lentiviral system.Conclusions: We reported a novel lentiviral vector with an optimal design of shRNA and inducible AGO2 overexpression which provides a new tool for RNAi research.Peer reviewedPhysiological Science
Influence of special coordination exercises on the level of policemen's self-defence skills
Introduction: The main aim of the study was to find out the impact of special coordination training on the level of technical skills in the field of self-defence on a policeman during basic vocational training. Method: The studies used the classical experiment method and the parallel group technique. The study was carried out using the classic experiment with a pre-test (1st measurement) and post-test (2nd measurement), and included the following groups: research (experimental teaching shaping coordination skills) and control (traditional teaching). Results: In both the experimental and traditional training groups, there was an improvement in the rating of defence against each of the three attacks. Simple effects analyses were performed, which showed that the increase in self-defence skills was higher in the experimental training group than in the traditional training group. Conclusions: Experimental training, which takes into account the development of coordination skills in its training, contributes to a better improvement of the ability to repel an attack than traditional training. A higher level of skills in the field of repelling an attack on a policeman allows for the conclusion that without the need to increase the number of hours of program training, it is possible to more effectively prepare policemen to act effectively, adequately and safely during an intervention
Interdependence of Shigella flexneri O Antigen and Enterobacterial Common Antigen Biosynthetic Pathways
Outer membrane (OM) polysaccharides allow bacteria to resist harsh environmental conditions and antimicrobial agents, traffic to and persist in pathogenic niches, and evade immune responses. Shigella flexneri has two OM polysaccharide populations, being enterobacterial common antigen (ECA) and lipopolysaccharide (LPS) O antigen (Oag); both are polymerized into chains by separate homologs of the Wzy-dependent pathway. The two polysaccharide pathways, along with peptidoglycan (PG) biosynthesis, compete for the universal biosynthetic membrane anchor, undecaprenyl phosphate (Und-P), as the finite pool of available Und-P is critical in all three cell wall biosynthetic pathways. Interactions between the two OM polysaccharide pathways have been proposed in the past where, through the use of mutants in both pathways, various perturbations have been observed. Here, we show for the first time that mutations in one of the two OM polysaccharide pathways can affect each other, dependent on where the mutation lies along the pathway, while the second pathway remains genetically intact. We then expand on this and show that the mutations also affect PG biosynthesis pathways and provide data which supports that the classical mutant phenotypes of cell wall mutants are due to a lack of available Und-P. Our work here provides another layer in understanding the complex intricacies of the cell wall biosynthetic pathways and demonstrates their interdependence on Und-P, the universal biosynthetic membrane anchor.Nicholas Maczuga, Elizabeth N. H. Tran, Jilong Qin, Renato Moron
Embedding siRNA sequences targeting Apolipoprotein B100 in shRNA and miRNA scaffolds results in differential processing and in vivo efficacy
Cellular mechanisms in basic and clinical gastroenterology and hepatolog
Therapeutic expression of hairpins targeting apolipoprotein B100 induces phenotypic and transcriptome changes in murine liver
Constitutive expression of short hairpin RNAs (shRNAs) may cause cellular toxicity in vivo and using microRNA (miRNA) scaffolds can circumvent this problem. Previously, we have shown that embedding small interfering RNA sequences targeting apolipoprotein B100 (ApoB) in shRNA (shApoB) or miRNA (miApoB) scaffolds resulted in differential processing and long-term efficacy in vivo. Here we show that adeno-associated virus (AAV)-shApoB- or AAV-miApoB-mediated ApoB knockdown induced differential liver morphology and transcriptome expression changes. Our analyses indicate that ApoB knockdown with both shApoB and miApoB resulted in alterations of genes involved in lipid metabolism. In addition, in AAV-shApoB-injected animals, genes involved in immune system activation or cell growth and death were affected, which was associated with increased hepatocyte proliferation. Subsequently, in AAV-miApoB-injected animals, changes of genes involved in oxidoreductase activity, oxidative phosphorylation and nucleic bases biosynthetic processes were observed. Our results demonstrate that long-term knockdown of ApoB in vivo by shApoB or miApoB induces several transcriptome changes in murine liver. The increased hepatocyte profileration by AAV-shRNA may have severe long-term effects indicating that AAV-mediated RNA interference therapy using artificial miRNA may be a safer approach for familial hypercholesterolemia therap