Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Channel Islands”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources

Is childhood allergy more common amongst an island population?

A rise in the prevalence of childhood asthma has been reported in both the UK and in several overseas countries during recent years. Wide geographical variations have also been demonstrated in the distribution of hay fever, atopic eczema and other allergic symptoms. It is the impression of many parents and some clinicians that allergic symptoms may be even higher amongst children in an island environment compared with a similar population on the mainland. To test this hypothesis, Guernsey and Jersey in the Channel Islands, and the Isle of Man in the Irish Sea participated as an independent arm in the International Study of Asthma and Allergy in Childhood (ISAAC). This entailed self-completion of a 38-part pretested and validated questionnaire in a classroom setting under standardised conditions. A total of 3,772 secondary students in school years eight and nine living in the three islands were compared with 27,507 students of similar age in 93 British secondary schools enrolled in the larger UK study. There are a number of demonstrable differences in climate, home environment and lifestyle factors between the islands and mainland UK. Although results were generally above the UK mean, they were comparable with the reference region of South West England and invariably below the UK maximum. For instance, the prevalence of 'ever wheezed?', 'wheezed in last twelve months?', 'wheezed with exercise?' and 'diagnosis of asthma' were a mean of 50.5%, 34.5%, 31% and 19.7% in the islands compared with a UK prevalence of 48.8%, 33.3%, 28.5% and 20.7%, whilst the prevalence of 'runny nose ever?' and 'runny nose in last twelve months?' was a mean of 46.6% and 36.7% in the islands, compared with 47.1% and 37.9% in the UK mean. These differences were not statistically significant. This information will be reassuring to parents of island children, and also demonstrates that services for the management of asthma and other allergic conditions should not be a higher public health priority in these locations than on the mainland of Britain.

Adolescent↗

Rapid dwarfing of red deer on Jersey in the last interglacial.

The dwarfing of large mammals on islands occurred repeatedly in the Pleistocene. Elephants, deer, hippopotami and other species became dwarfed on islands in Indonesia, the Mediterranean, the east Pacific and elsewhere. In most cases, the full-sized ancestral form can be recognized among the adjacent mainland fauna, but evolutionary rates cannot be estimated because the entry of the ancestor onto the island, and appearance of the dwarf form, are poorly dated. Here I give the first example in which the island dwarf is well dated, the full-sized ancestor is found in demonstrably older deposits on the island, and a good estimate can be made for the duration of the isolation leading to dwarfing. In the Last Interglacial, red deer on Jersey, Channel Islands, became reduced to one sixth of their body weight in less than six thousand years.

Animals↗

Population genetic structure of and inbreeding in an insular cattle breed, the Jersey, and its implications for genetic resource management.

The Jersey is a ubiquitous and successful breed of cattle that originates from the UK Channel Island of Jersey. While the breed has been exported extensively, no imports have taken place to the island since 1789, leading to a concern regarding possible losses of genetic diversity and increased inbreeding. We have conducted the first large-scale genetic analysis of the Jersey cattle using only samples from the island. A total of 223 cattle from all parishes except one were genotyped for 12 microsatellite loci. The average number of alleles per locus and expected heterozygosity were found to be comparatively high (n(A)=4, H(e)=0.64) with respect to that observed in a number of continental breeds. Only breeds that have been upgraded and are therefore the result of admixture are clearly more variable than the Jersey. We also found a significant but limited amount of genetic differentiation between parishes (F(st)=0.013), or even between farms (F(st)=0.035) despite an apparent lack of movement. This is confirmed by the application of two recent statistical methods. A Bayesian partition analysis shows that the most probable value of K, the number of possible hidden partitions, is 1 (P approximately 0.98). K=2 has a much lower probability (P approximately 0.02) while other values are essentially zero. Similarly, we were able to show that there was no support for departure from panmixia other than due to population structure, and thus that there is sufficient background gene flow across the island to overcome local drift. Overall, it appears that the current level of genetic diversity and its distribution within the island means it is unnecessary to import unrelated genetic material to the island for management purposes.

Alleles↗

The use of genetic relationships among cattle breeds in the formulation of rational breeding policies: a re-examination of the example of the South Devon and the Gelbvieh.

It has been claimed that the origin of the South Devon breed of cattle is 'unknown' and that biochemical polymorphisms '. . . indicate that Gelbvieh and South Devon had a common ancestry on the Continent and are distinct from other British breeds such as Hereford, Angus and Jersey' (Kidd et al., 1974). In fact, historical records indicate that the South Devon evolved largely from native Devon cattle and is a close relative of other English Lowland breeds such as the North Devon and Hereford. Information about crosses from other breeds makes no mention of the Gelbvieh but emphasises the contribution of Channel Island breeds, especially the Guernsey. Data for biochemical polymorphisms in the relevant breeds show agreement with the historical information and with the biogeography of the breeds involved.

Amylases↗

The use of microsatellite variation to infer population structure and demographic history in a natural model system.

To assess the reliability of genetic markers it is important to compare inferences that are based on them to a priori expectations. In this article we present an analysis of microsatellite variation within and among populations of island foxes (Urocyon littoralis) on California's Channel Islands. We first show that microsatellite variation at a moderate number of loci (19) can provide an essentially perfect description of the boundaries between populations and an accurate representation of their historical relationships. We also show that the pattern of variation across unlinked microsatellite loci can be used to test whether population size has been constant or increasing. Application of these approaches to the island fox system indicates that microsatellite variation may carry considerably more information about population history than is currently being used.

Animals↗

Pseudotuberculosis in marmosets, tamarins, and Goeldi's monkeys (Callithrichidae/Callimiconidae) housed at a European zoo.

Yersinia pseudotuberculosis is an insidious bacterial infectious agent distributed worldwide and endemic to European countries. It has caused several animal deaths and may threaten the effectiveness of breeding projects for endangered species. In this retrospective study, we examine the prevalence of pseudotuberculosis in Jersey Zoo (Channel Islands, U.K.) over a period of 16 yr to obtain information that can be applied to prevent the infection. The efforts made to control the disease through vaccination are also explored. Our results show that pseudotuberculosis has been endemic to Jersey Zoo since 1979 and is responsible for significant animal loss in the Callithrichidae/Callimiconidae group. Mortality due to Y. pseudotuberculosis was seasonal; a high percentage of deaths occurred during wet and cold seasons. No significant difference was found in mortality rates of vaccinated versus nonvaccinated animals. Although the efficacy of vaccination has not been confirmed, we believe that an improved vaccination program could be an important tool in controlling outbreaks of infection in marmosets and tamarins.

Animals↗

District nursing staff and depression: a psychometric evaluation of Depression Attitude Questionnaire findings.

BACKGROUND: Mental health problems such as depression are common in primary care settings and patients with chronic medical problems are at an increased risk. This co-morbidity suggests that district nursing services are particularly likely to encounter psychological problems in their patients. Mental health problems are poorly recognised and inadequately treated in primary care. In part this may be due to stigmatising views of mental illness, which negatively influence help-seeking and user experiences. Likewise providers' attitudes are likely to play a significant part in the management of such problems. OBJECTIVES: The aims of this study were extend knowledge of district nursing staff attitudes to depression and explore the psychometric properties of a depression attitude measure used with this staff group. DESIGN AND SETTINGS: The Depression Attitude Questionnaire (DAQ) was used within a postal questionnaire survey of district nursing services in three areas, Jersey (Channel Islands), Lewisham, and Hertfordshire. PARTICIPANTS: All staff (community nurses, district nurses and home care staff) were contacted; 217 (66%) staff responded to the survey, and 189 (57%) completed the DAQ. RESULTS: Three factors were derived from the DAQ accounting for 47% of the variance. The factor solution appeared stable and provided meaningful dimensions, however the internal consistency of the measure and of its derived subscales was low (Cronbach's alpha between 0.59 and 0.64). The factors were labelled pessimism about depression and its treatment, tendency to defer to specialists, and professional ease in working with depressed patients. Staff responses revealed generally optimistic views concerning depression treatment, strongly rejecting deterministic attitudes to this condition. CONCLUSIONS: The DAQ has been widely employed to measure and compare attitudes of staff from various disciplines and specialisms. The current evaluation has provided a more detailed examination of its psychometric properties than previously available, but low internal consistency levels indicate further examination of this area is warranted.

Analysis of Variance↗

District nurses' involvement and attitudes to mental health problems: a three-area cross-sectional study.

AIMS AND OBJECTIVES: The main aims of this study were to obtain information on the extent of staff contact and input with mental health problems and to determine their experience, training and attitudes to such problems. BACKGROUND: Historical changes and policy shifts have resulted in primary care providers playing an increasing role in the care of mental health problems. Such problems are common within community settings and a major cause of suffering and disability. District nurses in particular are likely to encounter a high level of psychological co-morbidity in their patients. Information is lacking on their involvement, attitudes and specific training for this area of their work. DESIGN AND METHODS: A cross-sectional study was conducted of the staff of district nursing services in three areas, Jersey (Channel Islands), Lewisham and Hertfordshire, using a postal questionnaire. RESULTS: Questionnaires were sent to 331 staff; 66% responded. Community and district nurses estimated a 16% prevalence of mental health problems among their patients, most commonly dementia, depression and anxiety disorders. Staff noted participation in a wide range of psychological care activities, but identified a lack of training for this aspect of their role (three-quarter of nurses had received no such training during the past five years). They reported a willingness to develop their understanding and skills by means of educational programmes. Attitude measures revealed generally optimistic views concerning depression treatment, a rejection of deterministic attitudes about this condition and confidence in the role of district nursing staff in managing such problems. CONCLUSIONS: The need for primary care mental health training is widely noted and based upon consistent evidence of the limited detection and treatment of these problems. This study has employed quantitative methods to clarify the extent and nature of district nursing staff involvement in this area of practice and indicates that training needs are acknowledged by community nurses from geographically distinct settings. RELEVANCE TO CLINICAL PRACTICE: Staff are interested in developing knowledge and skills pertinent to the psychological problems of their patients and their views reveal a consensus that the most important areas for learning are recognition of mental disorders, anxiety management, crisis intervention and pharmacological treatments for depression.

Adult↗

Microevolution in island rodents.

We perform a meta-analysis on morphological data from four island rodent populations exhibiting microevolution (< approximately/= 100 years). Data consisting of incidences of skeletal variants, cranial, and external measurements are from house mice (Mus musculus) on one Welsh and one Scottish island, black rats (Rattus rattus) on two Galapagos islands, and deer mice (Peromyscus maniculatus) on three California Channel islands. We report extremely high rates of microevolution for many traits; 60% of all mensural traits measured changed at a rate of 600 d or greater (max. 2682 d). The proportion of all mensural traits evolving at 600-800 d (23%) was idiosyncratic and departed from an expected negative exponential distribution. We argue that selection, rather than founder events, is largely responsible for the substantial shifts in morphology seen among insular rodents. Examining individual traits, there is a trend towards the nose becoming longer and wider, while the skull becomes shallower, shown by both rats and mice on five different islands. We found a significant correlation between island size and degree of skeletal variant evolution and between island distance from the mainland (or nearest island) and degree of cranial and external character evolution. Thus, microevolution of rodents is greater on smaller and more remote islands.

Animals↗

Xantusiid "night" lizards: a puzzling phylogenetic problem revisited using likelihood-based Bayesian methods on mtDNA sequences.

Contentious issues in Night Lizard (Xantusiidae) evolution are revisited using Maximum Likelihood-based Bayesian methods and compared with results from Neighbor-Joining and Maximum Parsimony analyses. Fragments of three mitochondrial genes, the 12S and 16S ribosomal genes, and the cytochrome b gene, are sampled across an ingroup composed of seven xantusiid species and a 12-species outgroup chosen to bracket ancestral states for six additional clades of scleroglossan lizards. Our phylogenetic analyses afford robust support for the following conclusions: Xantusiidae is part of Scincomorpha, rather than being allied with Gekkota; Lepidophyma is sister to Xantusia, rather than to Cricosaura; Xantusia riversiana is imbedded within, rather than being sister to, other Xantusia species; and rock-morph Xantusia are not closely related to one another. Convergence related to retarded rates of growth and development, or to physical constraints imposed by living in rock crevices, may be responsible for much of the character discordance underlying conflicts in xantusiid phylogeny. Fossil-calibrated Maximum Likelihood-based divergence time estimates suggest that although the xantusiid stem may have originated in the Mesozoic, the crown clade is exclusively Tertiary in age. Thus, the clade including extant Cricosaura does not appear to have been extant during the K-T boundary bolide impact, as has been suggested. Moreover, our divergence-time estimates indicate that the xantusiid island endemics, Cricosaura typica on Cuba and Xantusia riversiana on the California Channel Islands, arrived via dispersal rather than vicariance, as previously proposed.

Animals↗

Spatial and temporal variation in the seroprevalence of canine heartworm antigen in the island fox.

Island foxes (Urocyon littoralis) are endemic to six of the eight California Channel Islands (USA). The island fox is classified as a threatened species by the State of California, and recently three of the six subspecies have experienced abrupt population declines. As part of a continuing effort to determine the cause of the declines, we tested island fox serum samples collected in 1988 (n = 176) and 1997-98 (n = 156) over the entire geographic range of the species for seroprevalence of canine heartworm (Dirofilaria immitis) antigen. Using a commercially available enzyme-linked immunosorbent assay (PetChek, Idexx Laboratories, Westbrook, Maine, USA) we detected heartworm antigen in four of the six populations of island foxes. On San Miguel and Santa Rosa Islands, seroprevalence in adult foxes was >85% (n = 62) in 1988 and increased to 100% (n = 24) in 1997-98. On Santa Cruz Island, seroprevalence in adult foxes decreased from 83% (n = 30) to 58% (n = 26), whereas on San Nicolas Island, seroprevalence increased from 25% (n = 32) to 77% (n = 30) during the same period. All of the pups assayed (n = 33) were seronegative. The seroprevalences of heartworm reported herein for the four populations of island foxes are the highest yet reported for a fox species. However, additional demographic data reported elsewhere suggests that heartworm has not been a major factor in the recent declines of island fox populations.

Animals↗

Cryptic species related to Daldinia concentrica and D. eschscholzii, with notes on D. bakeri.

Daldinia macaronesica (from the Canary Islands and Madeira), D. palmensis (from the Canary Islands), D. martinii and D. raimundi (from Sicily), and D. vanderguchtiae (from Jersey, Channel Islands) spp. nov., are described, based on new combinations of teleomorphic and anamorphic characters. They all resemble the pantropical D. eschscholzii and/or the European D. concentrica with regard to teleomorphic characters and secondary metabolite profiles generated by analytical HPLC. The status of the newly described taxa was established by SEM of ascospores and microscopic studies of their anamorphs in comparison with various materials of the aforementioned known species. HPLC and SEM studies on the holotype of D. bakeri confirmed its relationships to D. fissa and D. loculata. Yellowish pigments contained in the type specimen of D. bakeri are probably artificial.

Chromatography, High Pressure Liquid↗

Golden eagles, feral pigs, and insular carnivores: how exotic species turn native predators into prey.

Island ecosystems are particularly vulnerable to exotic species. Here we show how an introduced prey has led to the wholesale restructuring of an island food web, including the near extinction of an endemic carnivore. Introduced pigs, by providing abundant food, enabled golden eagles to colonize the California Channel Islands. Eagles preyed heavily on the island fox, whose resulting decline toward extinction released populations of the competitively inferior island skunk. The presence of exotic pigs led to major ecosystem shifts by indirectly causing predation to replace competition as the dominant force shaping these island communities.

Animals↗

Genetic differences between the endangered San Clemente Island loggerhead shrike Lanius ludovicianus mearnsi and two neighbouring subspecies demonstrated by mtDNA control region and cytochrome b sequence variation.

We investigated mtDNA sequence variation in five populations of the loggerhead shrike Lanius ludovicianus, representing four subspecies, including the San Clemente logger-head shrike L. l. mearnsi, a critically endangered California Channel Island endemic. Variability in 200 bp of control region and 200 bp of cytochrome b was extremely low, and defined four haplotypes. Strong structure was apparent among all three southern California subspecies, including L. l. mearnsi, with one haplotype predominating in each subspecies. Although potential levels of gene flow between L. l. mearnsi and neighbouring populations are low, mtDNA data support field observations that some shrikes visit the island during winter but do not stay to breed, and suggest that these birds come from the mainland. The similarity in haplotypes between populations from Saskatchewan, Canada and those in southern California suggests post-glacial northern range expansion of the species. Our results confirm the evolutionary distinctiveness of L. l. mearnsi and justify continuing efforts for its conservation.

Animals↗

Estimating gene flow in island populations.

A new method is presented for estimating the rate of gene flow into island populations using the distribution of alleles in samples from a number of islands. The pseudo maximum likelihood estimator (PMLE) that we derive may be applied to species with either discrete or continuous generation times. For Wright's discrete-generation island model, the method provides an estimate of theta = 2Nm where N is the (haploid) population size on each island and m is the fraction of individuals replaced by immigrants in each generation. For a continuous-generation island model, the corresponding parameter theta is the ratio of the immigration rate phi to the individual birth rate lambda. Monte Carlo simulations are used to compare the statistical properties of the PMLE with those of two alternative estimators of theta derived from Wright's F-statistics. The PMLE is shown to have greatest efficiency (least mean square error) in most cases for a wide range of sample sizes and parameter values. The PMLE is applied to estimate theta using mtDNA haplotypes and allozymes for subdivided populations of African elephants and Channel Island foxes.

Alleles↗

Association of prokaryotes with symptomatic appearance of withering syndrome in black abalone Haliotis cracherodii.

Withering syndrome (WS) is an epizootic fatal wasting disease that is devastating California Channel Island populations of black abalone Haliotis cracherodii. Our studies suggest a strong pathogen-disease association. The pathogen is an intracellular prokaryote that infects epithelial cells lining the gut and enzyme secreting cells of the digestive diverticula. It multiplies by binary fission in round to oval, basophilic, membrane-bound colonies teeming in the cytoplasm. Infection of the digestive diverticula is accompanied by a complete loss of digestive enzyme granules and metaplasia of enzyme secretory cells to a morphology similar to epithelium lining the gut. Extensive infection of digestive diverticular cells and the resultant deficiency in digestive enzymes correlates to the degree of pedal muscle atrophy and the severity of signs associated with WS. Electron microscopically the intracellular pathogen is a rod-shaped, ribosome-rich, gram-negative, prokaryote with a trilaminar cell wall consistent with the order Rickettsiales. Microbiological and protozoological methods produced no patterns that implicated other types of microbes. Chemical analysis of tissue from animals from a population with WS did not support an association between WS and environmental pollutant exposure to polycyclic aromatic hydrocarbons, polychlorinated biphenyls, or chlorinated pesticides.

Alphaproteobacteria↗

Genetic divergence of insular populations of deer mice.

Electrophoretic variants at 28 genetic loci were analyzed in subspecies of Peromyscus maniculatus endemic to the Channel Islands of the California coast. The genetic variability within insular populations was calculated. These deer mice have relatively high levels of polymorphism for insular populations. The mean heterozygosity per individual varies in the populations, being much higher on one of the islands than the others. Nei's measure of genetic distance between groups compared on the basis of electrophoretic variants was used. His estimate of time of divergence of these groups, based on genetic distance, is applicable particularly to closely related groups. The length of time each island population has been isolated from the others was calculated and found to be consistent with the periods of isolation estimated on the basis of geological data.

Alleles↗

Infection by a Hematodinium-like parasitic dinoflagellate causes Pink Crab Disease (PCD) in the edible crab Cancer pagurus.

The edible crab (Cancer pagurus) supports a large and valuable fishery in UK waters. Much of the catch is transported live to continental Europe in specially designed live-well ('vivier') vehicles. During the winter of 2000/2001, many trap-caught crabs from Guernsey, Channel Islands, UK, were reportedly moribund and pink in colour. These crabs generally died before and during vivier transportation. We provide histological, immunological, and molecular evidence that this condition is associated with infection by a Hematodinium-like dinoflagellate parasite similar to that previously reported in C. pagurus and to an infection causing seasonal mass mortalities of the Norway lobster (Nephrops norvegicus). Pathologically, every altered host bore the infection, which was characterised by very large numbers of plasmodial and vegetative stages in the haemolymph and depletion of reserve cells in the hepatopancreas. Due to the hyperpigmentation of the carapace and appendages, we have called this infection 'Pink Crab Disease' (PCD). Similar Hematodinium infections cause 'Bitter Crab Disease' in tanner and snow crabs, which has had a negative effect on their marketability. At present, little is known about the seasonality, transmission, and market impact of this infection in C. pagurus.

Animals↗