PubMed Health⌕ Search

Biomedical subjects

C J Manning

Publications and source records attributed to C J Manning.

7 recordsLinked to original sources
PubMed2005

Milk fluoridation: a comparison of dental health in two school communities in England.

OBJECTIVE: To compare levels of caries experience in children attending schools in Wirral that have a fluoridated milk programme with children in a similar community which does not have a fluoridated milk programme. STUDY DESIGN: A cross sectional study measuring caries experience in first permanent molars. Children were examined on an 'intention to treat' basis and the effect of clustering of children within schools was taken into account. PARTICIPANTS: 690 children in Wirral (test group) and 1,835 children in Sefton (comparison group) were examined for caries experience (DMFT/DT/DFS) in 2003. The mean ages of the children examined in the test and comparison groups were 10.79 and 10.83 years respectively. RESULTS: Mean DMFT/DT/DFS values were 1.01/0.59/1.20 respectively in the test group and 1.46/1.02/1.89 respectively in the comparison group. Multiple linear regression analysis taking clustering of children within schools into account and with the Index of Multiple Deprivation 2000 as an explanatory variable gave the coefficients and p-values for DMFT/DT/DFS of 0.49 (p < 0.001)/0.43 (p < 0.001)/0.74 (p < 0.001) respectively. CONCLUSION: A difference in children with caries experience of 13% and a difference in children with active decay of 16% was found when a district with a community fluoridated milk programme was compared with a district without a fluoridated milk programme.

Animals↗
PubMed1998

Cyclosporin A and hydroxycyclosporine (M-17) affect the secretory phenotype of human gingival fibroblasts.

The responsiveness of human gingival fibroblast populations to cyclosporin A (CsA) and its principal metabolite, hydroxycyclosporine (M17), was evaluated in cell culture. Gingival fibroblasts exhibited a dose-dependent accumulation and bell-shaped distribution of dansylated CsA. A 100-fold excess of non-labeled CsA prevented the accumulation of the fluorescent probe in the fibroblasts. Both CsA (400 ng/ml) and M17 (100 ng/ml) stimulated mean gingival fibroblast cell number to 23.2% and 36.7% above controls, and reduced mean collagen production by 37.7% and 37.4% below controls, respectively; however, neither CsA nor M17 affected mean protein production in comparison to control cultures. Analyses of responses to CsA and M17 by ligand-accumulating and non-accumulating fibroblasts sorted out from the parent cultures did not provide consistent interstrain responses either by cells representing the upper quartile of fluorescence or cells representing the bottom quartiles of fluorescence. These data demonstrate that CsA is accumulated by gingival fibroblasts and that CsA and M17 are potent modulators of gingival fibroblast phenotype.

Adolescent↗
PubMed1994

The role of infectious disease, inbreeding and mating preferences in maintaining MHC genetic diversity: an experimental test.

In house mice, and probably most mammals, major histocompatibility complex (MHC) gene products influence both immune recognition and individual odours in an allele-specific fashion. Although it is generally assumed that some form of pathogen-driven balancing selection is responsible for the unprecedented genetic diversity of MHC genes, the MHC-based mating preferences observed in house mice are sufficient to account for the genetic diversity of MHC genes found in this and other vertebrates. These MHC disassortative mating preferences are completely consistent with the conventional view that pathogen-driven MHC heterozygote advantage operates on MHC genes. This is because such matings preferentially produce MHC-heterozygours progeny, which could enjoy enhanced disease resistance. However, such matings could also function to avoid genome-wide inbreeding. To discriminate between these two hypotheses we measured the fitness consequences of both experimentally manipulated levels of inbreeding and MHC homozygosity and heterozygosity in semi-natural populations of wild-derived house mice. We were able to measure a fitness decline associated with inbreeding, but were unable to detect fitness declines associated with MHC homozygosity. These data suggest that inbreeding avoidance may be the most important function of MHC-based mating preferences and therefore the fundamental selective force diversifying MHC genes in species with such mating patterns. Although controversial, this conclusion is consistent with the majority of the data from the inbreeding and immunological literature.

Animals↗
PubMed1992

Communal nesting patterns in mice implicate MHC genes in kin recognition.

House mice (Mus musculus domesticus) form communal nests and appear to nurse each other's pups indiscriminately. Communal nesting probably functions to reduce infanticide, but it also makes females vulnerable to exploitation if nursing partners fail to provide their fair share of care. Kinship theory predicts that females will preferentially form communal nests with relatives to minimize exploitation and further increase inclusive fitness. Here we provide evidence from seminatural populations that females prefer communal nesting partners that share allelic forms of major histocompatibility complex genes. Such behaviour would lead to the selection of close relatives as communal nesting partners. Although criteria for the demonstration of kin recognition are currently embroiled in controversy, this is the first vertebrate study to meet Grafen's restrictive requirements: discrimination is based on genetic similarity at highly polymorphic loci, incidental correlations due to relatedness are experimentally controlled, and strong reasons exist for expecting the assayed behaviour to be kin-selected.

Animals↗
PubMed1991

Mating patterns in seminatural populations of mice influenced by MHC genotype.

Because of the central role of major histocompatibility complex (MHC) genes in immune recognition, it is often assumed that parasite-driven selection maintains the unprecendented genetic diversity of these genes. But associations between MHC genotype and specific infectious diseases have been difficult to identify with a few exceptions such as Marek's disease and malaria. Alternatively, MHC-related reproductive mechanisms such as selective abortion and mating preferences could be responsible for the diversity. To determine both the nature and strength of selection operating on MHC genes by we have studied components of selection in seminatural populations of mice (Mus musculus domesticus). Here we assess MHC-related patterns of reproduction and early (preweaning) mortality by analysing 1,139 progeny born in nine populations, and 662 progeny from laboratory matings. Reproductive mechanisms, primarily mating preferences, result in 27% fewer MHC-homozygous offspring than expected from random mating. MHC genotype had no detectable influence on neonatal (preweaning) mortality. These mating preferences are strong enough to account for most of the MHC genetic diversity found in natural populations of Mus.

Animals↗
PubMedDate not supplied

Noise control in the transportation corridor.

This paper considers the opportunities for noise control within the route corridor required for construction of road, rail and other guided transport schemes. It deals with control of noise generation at source, and in the transmission path close to the point of generation. In this way it is possible to control the amount of acoustic power generated, and to absorb part of the radiated power at points of reflection. Purely reflective wayside barriers do little to absorb acoustic energy, merely reflecting it in a different direction. Whilst this has selfish benefits to the receptor in the shadow zone of the barrier, it makes things worse for others on the reflective side of the geometry. The paper therefore considers the options available to the engineer in the design of rolling and sliding interfaces and the use of acoustically absorptive finishes on all surfaces close to the point of noise generation. This includes the running surface itself, structural components, retaining walls, over and under passes, and the inner surfaces of track and wayside barriers.

Aircraft↗