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N Jennings

Publications and source records attributed to N Jennings.

8 recordsLinked to original sources
PubMed2006

Differences in the response of a striped dolphin (Stenella coeruleoalba) and a harbour porpoise (Phocoena phocoena) to an acoustic alarm.

Small cetacean bycatch in gillnet fisheries may be reduced by deterring odontocetes from nets acoustically. However, different odontocete species may respond differently to acoustic signals from alarms. Therefore, in this study a striped dolphin and a harbour porpoise were subjected simultaneously to sounds produced by the XP-10 experimental acoustic alarm. The alarm produced 0.3s tonal signals randomly selected from a set of 16 with fundamental frequencies between 9 and 15kHz, with a constant pulse interval of 4.0s (duty cycle 8%) and a Source Level range of 133-163dB re 1muPa (rms). The effect of the alarm was judged by comparing the animals' respiration rate and position relative to the alarm during test periods with those during baseline periods. As in a previous study on two porpoises with the same alarm, the porpoise in the present study reacted strongly to the alarm by swimming away from it and increasing his respiration rate. The striped dolphin, however, showed no reaction to the active alarm. Based on harbour porpoise audiograms and the specific audiogram of the striped dolphin in the present study, and the low background noise levels during the experiment, both animals must have heard the alarm signals clearly. This study indicates that cetacean species are not equally sensitive to human-made noise disturbance. Therefore, source levels of acoustic alarms should be adapted to the species they are supposed to deter. In addition, alarms should be tested on each odontocete species for which they are intended to reduce bycatch.

Acoustic Stimulation↗
PubMed2006

Definition of novel GP6 polymorphisms and major difference in haplotype frequencies between populations by a combination of in-depth exon resequencing and genotyping with tag single nucleotide polymorphisms.

BACKGROUND: Common genetic variants of cell surface receptors contribute to differences in functional responses and disease susceptibility. We have previously shown that single nucleotide polymorphisms (SNPs) in platelet glycoprotein VI (GP6) determine the extent of response to agonist. In addition, SNPs in the GP6 gene have been proposed as risk factors for coronary artery disease. METHODS: To completely characterize genetic variation in the GP6 gene we generated a high-resolution SNP map by sequencing the promoter, exons and consensus splice sequences in 94 non-related Caucasoids. In addition, we sequenced DNA encoding the ligand-binding domains of GP6 from non-human primates to determine the level of evolutionary conservation. RESULTS: Eighteen SNPs were identified, six of which encoded amino acid substitutions in the mature form of the protein. The single non-synonymous SNP identified in the exons encoding the ligand-binding domains, encoding for a 103Leu > Val substitution, resulted in reduced ligand binding. Two common protein isoforms were confirmed in Caucasoid with frequencies of 0.82 and 0.15. Variation at the GP6 locus was characterized further by determining SNP frequency in over 2000 individuals from different ethnic backgrounds. CONCLUSIONS: The SNPs were polymorphic in all populations studied although significant differences in allele frequencies were observed. Twelve additional GP6 protein isoforms were identified from the genotyping results and, despite extensive variation in GP6, the sequence of the ligand-binding domains is conserved. Sequences from non-human primates confirmed this observation. These data provide valuable information for the optimal selection of genetic variants for use in future association studies.

Amino Acid Sequence↗
PubMed2003

Equine vaccine for West Nile virus.

To meet the urgent need of controlling West Nile virus (WNV) infection in the equine population, we have developed a killed WNV vaccine. A dose titration study in horses was first conducted to evaluate serum neutralization antibody responses against WNV in these animals. Horses were vaccinated intramuscularly twice with the test vaccine at low, medium and high dose, three weeks apart. Serum samples were collected periodically and were measured for serum neutralizing antibody using a plaque reduction neutralization test. Significant increases in serum neutralizing antibody were detected in all three dosage groups 14 days post the second vaccination. Twelve months after the second vaccination, horses vaccinated with the medium dose of WNV vaccine and non-vaccinated control horses were experimentally challenged with WNV. Nine out of 11 (81.8%) controls developed viraemia after challenge while only one out of 19 (5.3%) vaccinates had transient viraemia, representing a 94% preventable fraction. In a separate study, the safety of the killed WNV vaccine was demonstrated under field conditions. A total of 648 horses, including 32 pregnant mares, were enrolled in the study. During the two weeks post vaccination period, no local or systemic adverse reactions were observed following 96% of the vaccinations administered while mild, transient injection site reactions were noted in a small number of horses. These results indicate that the killed WNV vaccine developed by Fort Dodge Animal Health is safe and efficacious.

Animals↗
PubMed2000

Characterization, cloning and immunogenicity of antigens released by transforming cercariae of Schistosoma mansoni.

A schistosome infection is initiated when the parasite penetrates the skin of a susceptible host. Relatively large quantities of protein are released by transforming cercariae compared to later larval stages. This represents the first parasite material to which the host's immune system is exposed, yet little is known about the proteins which are released during the first few hours post-transformation. We have shown that antiserum raised against such molecules was capable of imparting protection against a schistosome challenge infection upon passive transfer to naïve mice. By screening a cercarial cDNA library with this serum, 38 positive clones were identified. Sequence analysis showed these to represent 8 different molecules which included Schistosoma mansoni 21-7 kDa antigen, calcium-binding-protein and the vaccine candidate glutathione S-transferase (Sm28GST). In addition, 5 clones were isolated, 1 of which had significant homology to many cytochrome C proteins, another with leukocyte elastase inhibitors and 3 which represented novel molecules. Four clones were expressed in a prokaryotic high-level expression vector, sera produced against each purified recombinant protein and used subsequently to probe Western blots and parasite sections. The leukocyte elastase inhibitor homologue and 2 unknowns induced significant proliferation by lymph node cells recovered from mice vaccinated with irradiated cercariae. More strikingly, the 2 novel proteins stimulated very high levels of interferon gamma (IFNgamma) secretion both by lymph node cells and those recovered by broncho-alveolar lavage from the lungs of vaccinated mice. Such results will be discussed in the context of vaccine development.

Amino Acid Sequence↗
PubMed1991

The Kilkenny Integrated Oral Health Project.

The Kilkenny Health Project, started in 1985, aims to reduce the level of risk factors in the community for coronary heart disease through health promotion. Dental disease and coronary heart disease share risk factors of tobacco use, alcohol consumption and poor dietary patterns. A baseline oral health survey demonstrated significant levels of dental disease in Kilkenny in the 429 adults and 523 children who were examined there in 1987. Seventy one per cent of adults required treatment for periodontal disease and 49% of children surveyed required treatment for dental decay. The Kilkenny Oral Health Project was developed as a community participation project aiming to reduce the level of common risk factors in the community for coronary heart disease and dental disease. It has run parallel with the main Kilkenny Health Project and is one of the first health promotion projects which has an integrated health message preventing dental disease and coronary heart disease.

Adolescent↗
PubMedDate not supplied

Children and computers: new technology--old concerns.

Computer technology has ushered in a new era of mass media, bringing with it great promise and great concerns about the effect on children's development and well-being. Although we tend to see these issues as being new, similar promises and concerns have accompanied each new wave of media technology throughout the past century: films in the early 1900s, radio in the 1920s, and television in the 1940s. With the introduction of each of these technologies, proponents touted the educational benefits for children, while opponents voiced fears about exposure to inappropriate commercial, sexual, and violent content. This article places current studies on children and computers in a historical context, noting the recurrent themes and patterns in media research during the twentieth century. Initial research concerning each innovation has tended to focus on issues of access and the amount of time children were spending with the new medium. As use of the technology became more prevalent, research shifted to issues related to content and its effects on children. Current research on children's use of computers is again following this pattern. But the increased level of interactivity now possible with computer games and with the communication features of the Internet has heightened both the promise of greatly enriched learning and the concerns related to increased risk of harm. As a result, research on the effects of exposure to various types of content has taken on a new sense of urgency. The authors conclude that to help inform and sustain the creation of more quality content for children, further research is needed on the effects of media on children, and new partnerships must be forged between industry, academia, and advocacy groups.

Adolescent↗