377 research outputs found
Cytochrome oxidase subunit VI of Trypanosoma brucei is imported without a cleaved presequence and is developmentally regulated at both RNA and protein levels
No full textMitochondrial respiration in the African trypanosome undergoes dramatic developmental stage regulation. This requires co-ordinated control of components encoded by both the nuclear genome and the kinetoplast, the unusual mitochondrial genome of these parasites. As a model for understanding the co-ordination of these genomes, we have examined the regulation and mitochondrial import of a nuclear-encoded component of the cytochrome oxidase complex, cytochrome oxidase subunit VI (COXVI). By generating transgenic trypanosomes expressing intact or mutant forms of this protein, we demonstrate that COXVI is not imported using a conventional cleaved presequence and show that sequences at the N-terminus of the protein are necessary for correct mitochondrial sorting. Analyses of endogenous and transgenic COXVI mRNA and protein expression in parasites undergoing developmental stage differentiation demonstrates a temporal order of control involving regulation in the abundance of, first, mRNA and then protein. This represents the first dissection of the regulation and import of a nuclear-encoded protein into the cytochrome oxidase complex in these organisms, which were among the earliest eukaryotes to possess a mitochondrion
Diets of seabirds and consequences of changes in food supply
No full textResearch conducted by members of the Working Group on Seabird Ecology, on issues most likely to be raised within the ICES community concerning the foraging ecology of seabirds and waders, and the potential interactions between these groups of birds and fisheries.
A review of issues related to seabird consumption of fish and shellfish stocks, discards and mariculture as well as the trophic role and ecology of seabirds and waders: G. L. Hunt, W. A. Montevecchi, and M. F. Leopold.
Consumption of pre-recruit fish by seabirds and the possible use of this as an indicator of fish stock recruitment: S. P. R. Greenstreet, P. H. Becker, R. T. Barrett, P. Fossum, and M. F. Leopold.
Variation in prey taken by seabirds: M. L. Tasker, C. J. Camphuysen, and P.Fossum.
Evaluation of the role of discards in supporting bird populations and their effects on the species composition of seabirds in the North Sea: S. Garthe, U. Walter, M. L. Tasker, P. H. Becker, G. Chapdelaine, and R. W. Furness.
Exploration of the short-and medium-term consequences of a reduction in the amounts of fish discarded: M. L. Tasker, P. H. Becker, and G. Chapdelaine
Evidence for decadal scale variations in seabird population ecology and links with the North Atlantic oscillation: J. B. Reid, P. H. Becker, and R. W. Furness.
A review of the causes, and consequences at the population level, of mass mortalities of seabirds : C. J. Camphuysen, P. J. Wright, M. Leopold, O. Hüppop, and J. B. Reid.
</ol
Systemic administration of naloxone produces analgesia in BALB/c mice in the formalin pain test
No full textSystemic administration of naloxone usually produces either hyperalgesia or no change in nociception depending on the animal species used and/or the pain test employed. This study, however, demonstrates that naloxone produces a dose-dependent analgesia in the formalin pain test using an inbred strain of albino mouse. Female BALB/c, C57BL/6 and CD1 mice were injected subcutaneously with naloxone HCl in saline (0.1 10.0 mg/kg) or saline alone, and tested for analgesia using the formalin test. Naloxone produced a statistically significant dose-dependent analgesia in the BALB/c mice, with an ED50 of 0.24 mg/kg and almost total analgesia at doses of 1 mg/kg or greater. No changes in pain behaviour were observed in the C57BL/6 or CD1 strains of mice. We believe this to be the first report of analgesia following administration of doses of naloxone normally used for opioid antagonism. To determine if this effect was specific to the formalin test, the 3 strains of mice were injected subcutaneously with naloxone HCl and tested in the tail-flick test. Naloxone had no analgesic action in this test in any of the strains.LR: 20031114; PUBM: Print; JID: 7600130; 465-65-6 (Naloxone); 50-00-0 (Formaldehyde); ppublishSource type: Electronic(1
Rapid development of tolerance to morphine in the formalin test
No full textPrevious reports have suggested that tolerance to the antinociceptive effects of morphine does not develop in the formalin test. To re-examine these findings, morphine was administered via multiple injections or continuous infusion from 0 to 4 days prior to testing with either the formalin or tail-flick test. Following twice daily injections (5.0 mg kg-1 s.c.), significant tolerance developed within 2 days with the formalin test but not until day 4 with the tail-flick test. Significant tolerance was noted with both tests 4 days following the implantation of osmotic mini-pumps (10 mg kg-1 day-1, s.c.). We conclude that in mice, tolerance to the analgesic effects of morphine develops rapidly with the formalin test.LR: 20061115; PUBM: Print; JID: 9100935; 50-00-0 (Formaldehyde); 57-27-2 (Morphine); ppublishSource type: Electronic(1
Changes in behaviour and C-fos expression following administration of domoic acid at different stages of rat development
No full textAnalgesia produced by normal doses of opioid antagonists alone and in combination with morphine
No full textIn a recent study [30] it was reported that naloxone, at doses normally employed for opioid antagonism, produced a dose-dependent analgesia in BALB/c mice in the formalin test. We report here that another opioid antagonists, naltrexone, also produces analgesia under these conditions. Female BALB/c mice were injected subcutaneously with naltrexone (0.01-1.0 mg/kg) or saline alone and tested for analgesia using the formalin test. Naltrexone produced a statistically significant dose-dependent analgesia, with an ED50 of 0.05 mg/kg and almost total analgesia at doses of 0.1 mg/kg or greater. To determine the relationship between naloxone analgesia and better documented forms of opioid analgesia, BALB/c mice were injected with naloxone or saline following the administration of a pre-determined ED50 for morphine and tested for analgesia using the tail-flick and formalin tests. Naloxone antagonized morphine analgesia in the tail-flick test at both doses used (0.3 and 10 mg/kg). In the formalin test, however, naloxone attenuated morphine analgesia at the lower doses (0.1 and 0.3 mg/kg) and potentiated morphine analgesia at the highest dose (10 mg/kg). The implications of this finding are discussed.LR: 20061115; PUBM: Print; JID: 7508686; 0 (Receptors, Opioid); 16590-41-3 (Naltrexone); 465-65-6 (Naloxone); 57-27-2 (Morphine); ppublishSource type: Electronic(1
Making sense of health education in the Solomon Islands.
No full textThis article explores both the process and outcomes of a working Partnership between Solomon Islands College for Higher Education and the University of Waikato that explored the development of the initial teacher education health education courses. Through a process of co-construction and inquiry, teacher educators from the Solomon Islands and New Zealand developed a metaphorical context-specific model to represent understandings of health education in the Solomon Islands. The model and what this has meant for teaching and learning in health education at both SOE and in schools is examined
Traumatic Brain Injury and Pediatric Acute Respiratory Distress Syndrome: Moving the Field Forward*
No full text- …
