The incidence of spontaneously occurring antiliver antibodies in New Zealand Black mice

The sera of NZB/BL mice have been found to be active in the complement fixation test against isogeneic liver antigens to a higher titre than the sera of CBA, C57BL and DBA/2 mice. Six sera from NZB mice were fractionated by zone ultracentrifugation in sucrose density gradients and the anti-liver activity was found to sediment with the high molecular weight immunoglobulin. No correlation was found between complement-fixing activity against liver antigens and the presence of globulin on red cells (positive direct Coombs test).     

Naturally occurring double-stranded RNA and immune responses. Effects on plaque-forming cells and antibody formation.

A highly purified preparation of double-stranded RNA, obtained from virus-like particles in Penicillium cultures, was found to affert humoral immune responses in mice differentially depending on its time of administration in realtion to antigen. Double-stranded RNA administered with antigen, or a few hours after antigen, produced a variable degree of enhancement of plaque-forming cell numbers or agglutinating antibody levels depending on the antigen involved. Administration of double-stranded RNA 24 hours before antigen invariably produced a suppressed response. In mice which were either specifically hyporesponsive (tolerant) or non-specifically hyporesponsive (due to age or immunosuppressive drugs) double-stranded RNA administered with antigen resulted in a nearly normal immune response.     

Fluoride rinsing and dental health inequalities in 11-year-old children: an evaluation of a supervised school-based fluoride rinsing programme in Edinburgh

Abstract – Objectives: Previous studies have shown that fluoride mouthrinsing programmes are effective in reducing caries among children and adolescents. National surveys of child dental health in the UK confirm that there is variation in oral health. In particular, children of low socioeconomic status in Scotland have a disproportionately high share of dental disease. This study aimed to evaluate an existing school‐based fluoride mouthrinsing programme on dental caries in populations stratified by socioeconomic status. Methods: A random sample of 1333 children surveyed by the National Dental Inspection Programme with average age 11.4 years was included in the study. Caries prevalence data were collected for the 661 rinsers and 672 nonrinsers. Chi‐squared tests and t‐tests were carried out to test differences in proportion and in mean D₃MFT, respectively. The data were modelled using multilevel logistic regression, adjusting for age, sex, deprivation and rinse status. Results: There is a strong negative association between deprivation and prevalence of D₃MFT = 0. There is no significant difference in prevalence of D₃MFT between rinsers and nonrinsers, however, mean D₃MFT is greater for nonrinsers within each deprivation category. After adjusting for age, sex and deprivation, the odds of a tooth being decayed missing or filled for a child who rinsed are 0.79 (0.64, 0.98) compared with those of a child who did not. Conclusions: Fluoride rinsing can be effectively targeted at children from deprived areas through school‐based initiatives. There are some difficulties in recruiting all children from the more deprived backgrounds, but overall reductions in D₃MFT were observed.     

Neural mapping of prepulse‐induced startle reflex modulation as indices of sensory information processing in healthy and clinical populations: A systematic review

Startle reflex is modulated when a weaker sensory stimulus (“prepulse”) precedes a startling stimulus (“pulse”). Prepulse Inhibition (PPI) is the attenuation of the startle reflex (prepulse precedes pulse by 30–500 ms), whereas Prepulse Facilitation (PPF) is the enhancement of the startle reflex (prepulse precedes pulse by 500–6000 ms). Here, we critically appraise human studies using functional neuroimaging to establish brain regions associated with PPI and PPF. Of 10 studies, nine studies revealed thalamic, striatal and frontal lobe activation during PPI in healthy groups, and activation deficits in the cortico‐striato‐pallido‐thalamic circuitry in schizophrenia (three studies) and Tourette Syndrome (two studies). One study revealed a shared network for PPI and PPF in frontal regions and cerebellum, with PPF networks recruiting superior medial gyrus and cingulate cortex. The main gaps in the literature are (i) limited PPF research and whether PPI and PPF operate on separate/shared networks, (ii) no data on sex differences in neural underpinnings of PPI and PPF, and (iii) no data on neural underpinnings of PPI and PPF in other clinical disorders.