Vaccination strategies to enhance local immunity and protection against Mycobacterium tuberculosis

To determine the immunogenicity and protective efficacy of the Mycobacterium tuberculosis 10 kD culture filtrate protein (CFP10), and to evaluate strategies that enhance local immunity, we used C57Bl/6 DR4 mice that were transgenic for human HLA DRB1*0401, because CFP10 contains epitopes for DRB1*0401 but not for C57Bl/6 mice. Intramuscular immunization with a DNA vaccine encoding CFP10 elicited production of IFN-γ by systemic CD4+ T cells, and one intravenous dose of the CFP10-based DNA vaccine coated with polyethylenimine (PEI) stimulated IFN-γ production by lung CD4+ cells and reduced the pulmonary bacillary burden. We conclude that CFP10 is a potential vaccine candidate and that coating vaccines with PEI enhances local protective immunity to tuberculosis.     

Effect of anodal and cathodal microamperage direct current electrical stimulation on injury potential and wound size in guinea pigs

Injury potential may have a regulatory role in the wound healing process, and exogenous electrical stimulation (ES) may mimic natural endogenous bioelectric current that can improve wound healing. Until now, the influence of externally applied ES on injury potential has not been demonstrated during the healing of acute wounds. Thirty-nine male guinea pigs were randomly divided into a control group (sham treatment) and two experimental groups: anodal and cathodal direct current (DC). A 2.5 cm-long full-thickness skin incision was made on each animal's dorsal region. Differential skin surface potential was measured before and immediately after the injury and also through day 21 of the healing period; wound surface area (WSA) was also measured throughout the 21-day healing period. Immediately after injury, wound potential significantly increased in all three groups, reaching a maximum on day 1 for the control and cathodal groups and day 3 for the anodal group (p < 0.05), then decreasing through the healing period. Wound potential returned to preinjury levels by the end of the healing period in the anodal group only. By days 19 and 21, wound potential had decreased more for the anodal group than the control group (p < 0.05). By day 15 for the anodal group and day 17 for the cathodal group, WSA had decreased more compared with the control group (p < 0.05). Anodal microamperage DC ES is appropriate for improving the healing of acute skin wounds because it causes both the wound surface to close and the wound potential to return to preinjury levels faster.     

Comparing children's and parents' perspectives of health outcome in paediatric hydrocephalus

This study exampled the properties of a child-completed version of the Hydrocephalus Outcome Questionnaire (cHOQ) and compared these with parental responses to the HOQ (parent version). This was a cross-sectional study in the outpatient clinics at three Canadian paediatric hospitals (Toronto, Vancouver, and Halifax). All cognitively-capable children with previously treated hydrocephalus who were aged between 6 and 19 years were eligible. Parents completed the HOQ and the Health Utilities Index Mark 3; children completed the cHOQ. A total of 273 children participated (146 males, 127 females; mean age 14 y 1 mo, SD 2 y 7 mo). Internal consistency of the cHOQ was 0.93 and test-retest reliability was 0.86 (95% confidence interval 0.78-0.92). Mother-child agreement and father-child agreement were 0.57 (0.40-0.68) and 0.62 (0.48-0.73) respectively. Agreement was higher for assessments of physical health, but lower for assessments of cognitive health and social-emotional health. There was greater parent-child agreement for older children. When there was disagreement, it seemed that children tended to rate their health better than their parents did. In older children with hydrocephalus, the cHOQ appears to be a scientifically reliable means of assessing long-term outcome. The differences in child and parent perceptions of health need to be appreciated when conducting outcome studies in this population.     

Testing assumptions of statistical learning: Is it long-term and implicit?

Statistical learning has been studied as a mechanism by which people automatically and implicitly learn patterns in the environment. Here, we sought to examine general assumptions about statistical learning, including whether the learning is long-term, and whether it can occur implicitly. We exposed participants to a stream of stimuli, then tested them immediately after, or 24 h after, exposure, with separate tests meant to measure implicit and explicit knowledge. To measure implicit learning, we analyzed reaction times during a rapid serial visual presentation detection task; for explicit learning, we used a matching questionnaire. Subjects’ reaction time performance indicated that they did implicitly learn the exposed sequences, and furthermore, this learning was unrelated to explicit learning. These learning effects were observed both immediately after exposure and after a 24-h delay. These experiments offer concrete evidence that statistical learning is long-term and that the learning involves implicit learning mechanisms.     

The articular surfaces of the proximal segment of ulna: Morphometry and morphomechanics based on digital image analysis and concepts of fractal geometry

Introduction

The elbow joint is a compound joint made of articulations in between the humerus, ulna and the radius. The coupling areas (joints) are of prime importance from the kinetic-biomechanical perspective and of potential inter-ethnic significance. These articulations can be affected by several pathologies that may require medical and surgical interference. This experimental analysis aims to infer data in relation to the morphometry of the proximal segment of the ulna and its articular surfaces represented by the greater sigmoid notch (trochlear notch) and lesser sigmoid notch (radial notch).

Expanding applications,accuracy, and interpretation of laser speckle contrast imaging of cerebral blood flow

Laser speckle contrast imaging (LSCI) provides a rapid characterization of cortical flow dynamics for functional monitoring of the microcirculation. The technique stems from interactions of laser light with moving particles. These interactions encode the encountered Doppler phenomena within a random interference pattern imaged in widefield, known as laser speckle. Studies of neurovascular function and coupling with LSCI have benefited from the real-time characterization of functional dynamics in the laboratory setting through quantification of perfusion dynamics. While the technique has largely been relegated to acute small animal imaging, its scalability is being assessed and characterized for both chronic and clinical neurovascular imaging.     

Genotoxicity of trichloroethylene in the natural milieu

Trichloroethylene (TCE) is a suspected genotoxic and carcinogenic compound which is usually present in the air, soil and water as pollutant. To estimate the genotoxic potential of TCE in a pure chemical form as well as an ingredient of the complex sample, Ames fluctuation test using TA98 and TA100 strains and Allium cepa genotoxicity assay were performed. For the genotoxicity analysis of TCE in natural milieu, the above mentioned tests were performed on the waste waters collected from two different stations of northern India namely Saharanpur and Aligarh, U.P., and these waste waters were supplemented with 50 and 100 mg/l of trichloroethylene. TCE alone was found to be non-genotoxic by both the testing system up to the range of 1000 mg/l concentration (data not shown). However, the test water samples supplemented with 100 mg/l of TCE, exhibited a significant increase in the genotoxicity compared with control by both the testing systems. In Ames fluctuation test, Mi(f) value was found to be increased by 41% and 53% with 100 mg/l of TCE supplemented Saharanpur and Aligarh waste water samples respectively, in the presence of S9 fraction compared with their respective controls. Allium cepa genotoxicity test also showed around 25% increase in total chromosomal aberration frequency following 100 mg/l TCE supplementation. However, supplementation of 50 mg/l TCE to the test water samples could not enhance the genotoxicity to a significant extent. From these results, we can conclude that TCE itself was non-genotoxic but it may promote mutation and/or DNA damage at a concentration of 100 mg/l under certain environmental conditions. We suggest that some chemicals in the test water samples might be interacting with TCE and/or metabolite(s) to cause the enhancement in genotoxicity. The mechanism of these synergistic effects should be explored further.