Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 66
Filter
Add more filters

Publication year range
1.
J Fish Biol ; 92(5): 1635-1644, 2018 May.
Article in English | MEDLINE | ID: mdl-29537067

ABSTRACT

This study assessed the usefulness of passing euthanized Atlantic salmon Salmo salar smolts through an Archimedean screw turbine to test for external damage, as compared with live, actively swimming smolts. Scale loss was the only observed effect. Severe scale loss was 5·9 times more prevalent in euthanized turbine-passed fish (45%) than the live fish (7·6%). Additionally, distinctive patterns of scale loss, consistent with grinding between the turbine helices and housing trough, were observed in 35% of euthanized turbine-passed smolts. This distinctive pattern of scale loss was not seen in live turbine-passed smolts, nor in control groups (live and euthanized smolts released downstream of the turbine), which suggests that the altered behaviour of dead fish in turbine flows generates biased injury outcomes.


Subject(s)
Environment , Power Plants , Salmo salar , Animal Migration , Animals , Swimming
2.
J Fish Biol ; 92(6): 1849-1865, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29603222

ABSTRACT

A total of 230 anadromous Salmo trutta (brown trout) were sampled in five sheltered coastal fjords (or sea lochs) on the Isle of Skye, Scotland, U.K., in 2016 at varying distances from active Atlantic salmon Salmo salar farms. Statistical models were developed to investigate potential correlations between salmon lice Lepeophtheirus salmonis burdens on S. trutta hosts and their proximity to S. salar farm cages. Significant correlations were found between lice burdens and fish fork length and proximity to the nearest S. salar farm. The probability of the presence of L. salmonis on fish hosts increased with fish host size and with distance from the nearest S. salar farm, but total lice burdens were highest in fish sampled near S. salar farms and decreased with distance. The proportion of different life-cycle stages of L. salmonis were also dependent on S. salar farm proximity, with higher juvenile lice numbers recorded at sites near S. salar farm cages. These results highlight the complexity of the relationship between S. trutta and L. salmonis infections on wild fish and emphasize the requirement of further research to quantify these effects to better inform conservation and management strategies, particularly in areas of active S. salar farm facilities.


Subject(s)
Aquaculture , Copepoda , Fish Diseases/transmission , Salmo salar/parasitology , Trout/parasitology , Animals , Female , Fish Diseases/parasitology , Male , Scotland
3.
J Fish Biol ; 88(2): 580-94, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26748995

ABSTRACT

This study revealed between-lake genetic structuring between Coregonus lavaretus collected from the only two native populations of this species in Scotland, U.K. (Lochs Eck and Lomond) evidenced by the existence of private alleles (12 in Lomond and four in Eck) and significant genetic differentiation (FST = 0·056) across 10 microsatellite markers. Juvenile C. lavaretus originating from eggs collected from the two lakes and reared in a common-garden experiment showed clear phenotypic differences in trophic morphology (i.e. head and body shape) between these populations indicating that these characteristics were, at least partly, inherited. Microsatellite analysis of adults collected from different geographic regions within Loch Lomond revealed detectable and statistically significant but relatively weak genetic structuring (FST = 0·001-0·024) and evidence of private alleles related to the basin structure of the lake. Within-lake genetic divergence patterns suggest three possibilities for this observed pattern: (1) differential selection pressures causing divergence into separate gene pools, (2) a collapse of two formerly divergent gene pools and (3) a stable state maintained by balancing selection forces resulting from spatial variation in selection and lake heterogeneity. Small estimates of effective population sizes for the populations in both lakes suggest that the capacity of both populations to adapt to future environmental change may be limited.


Subject(s)
Genetic Variation , Genetics, Population , Salmonidae/genetics , Alleles , Animals , Female , Gene Pool , Genotype , Lakes , Male , Microsatellite Repeats , Phenotype , Scotland
4.
J Fish Biol ; 84(5): 1614-9, 2014 May.
Article in English | MEDLINE | ID: mdl-24773546

ABSTRACT

Reported here are several deviations (n = 15; 1·96%) from typical morphology in a large sample (n = 767) of European brook lamprey Lampetra planeri from a single population in the Loch Lomond catchment; this includes one specimen bearing a true anal fin. A brief review of petromyzontid teratology is provided.


Subject(s)
Lampreys/abnormalities , Animals , Lakes , Scotland , Teratogenesis
6.
J Fish Biol ; 82(3): 1093-100, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23464566

ABSTRACT

Interspecific sneak male mating tactics between paired lamprey species are described for the first time. Although alternative mating tactics among petromyzontids have been described previously, including intraspecific sneak males, the presence of sneak male tactics between parasitic and non-parasitic forms suggests that high levels of gene flow between putative lamprey species could remain high, despite large body size discrepancies.


Subject(s)
Lampreys/physiology , Reproduction , Sexual Behavior, Animal , Animals , Female , Gene Flow , Lampreys/genetics , Male
7.
J Fish Biol ; 82(5): 1708-16, 2013 May.
Article in English | MEDLINE | ID: mdl-23639164

ABSTRACT

Lamprey-induced scarring of the nationally rare Coregonus lavaretus, a known host of a freshwater-resident population of European river lamprey Lampetra fluviatilis, was found to have declined precipitously since the establishment of several non-native fishes in Loch Lomond. Evidence presented in this study points to the possibility that L. fluviatilis in this lake may have altered its trophic ecology in response to the negative impact that non-native species, in particular ruffe Gymnocephalus cernuus, have had on their favoured host.


Subject(s)
Lampreys/physiology , Perciformes/parasitology , Salmonidae/parasitology , Animals , Introduced Species , Lakes , Population Dynamics , Scotland
8.
J Fish Biol ; 80(2): 387-407, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22268437

ABSTRACT

A key for three putative species apparently found in three geographic areas, i.e. Coregonus clupeoides (in Scotland), Coregonus stigmaticus (in England), and Coregonus pennantii (in Wales) given in a recent review was tested quantitatively using 544 individuals from nine populations. The classification success of the key was very low (27%). It was concluded that there is currently no robust evidence for the recognition of the three putative species. Furthermore, the use of phenotypic characters alone to distinguish putative species in postglacial fish species such as those of the genus Coregonus that show homoplasy in many of these traits is questioned. In the absence of further evidence, it was concluded that a single highly variable species best describes the pattern of phenotypic variation in these U.K. populations. On this basis it is argued that taxonomic subdivision of U.K. European coregonids is inappropriate and that Coregonus lavaretus should prevail as the species name applicable to all populations.


Subject(s)
Genetic Speciation , Phenotype , Salmonidae/classification , Animals , England , Genetic Variation , Salmonidae/genetics , Scotland , Wales
9.
Child Adolesc Social Work J ; 38(4): 449-461, 2021.
Article in English | MEDLINE | ID: mdl-34108798

ABSTRACT

There is a pressing need to equip youth-serving community organizations to respond to the unique needs of trauma-exposed children. Early prevention measures can be an effective means of redirecting children to self-regulatory healing, while facilitating their transition toward strength-based thriving. Sport can offer a powerful opportunity to reach these children; however there remains little information on how to effectively develop, deliver, evaluate, and sustain trauma-sensitive sport programs in a community context. The purpose of this paper is to outline a case study of integrating sport-based trauma-sensitive practices with BGC Canada's national Bounce Back League program. An interdisciplinary partnership of academic, community, and practice experts used a community-based participatory action research approach, paired with a knowledge translational approach, to guide the process of program development. Mixed methods (e.g., surveys, logbooks, interviews, focus groups, online communications) were used to generate ongoing insights of staff's training experiences, successes and challenges of program implementation, and potential impact of program on club members. Several stages of program development are described, including: (a) collaboratively planning the program; (b) piloting the program to three clubs; (c) adapting the program using pilot insights; (d) expanding the adapted program to ten clubs; and (e) creating opportunities to maintain, sustain, and scale-out practices throughout grant duration and beyond. Lessons learned regarding the leadership team's experiences in terms of developing, adapting, and integrating trauma-sensitive practices in this community context are shared. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10560-021-00776-7.

10.
J Fish Biol ; 77(10): 2391-404, 2010 Dec.
Article in English | MEDLINE | ID: mdl-21155790

ABSTRACT

Differences in stable-isotope values, morphology and ecology in whitefish Coregonus lavaretus were investigated between the three basins of Loch Lomond. The results are discussed with reference to a genetic investigation to elucidate any substructuring or spawning site fidelity. Foraging fidelity between basins of Loch Lomond was indicated by δ¹³C and δ¹5N values of C. lavaretus muscle tissue. There was, however, no evidence of the existence of sympatric morphs in the C. lavaretus population. A previous report of two C. lavaretus'species' in Loch Lomond probably reflects natural variation between individuals within a single mixed population.


Subject(s)
Ecosystem , Phenotype , Salmonidae/physiology , Animals , Carbon Isotopes/metabolism , Feeding Behavior , Female , Head/anatomy & histology , Male , Microsatellite Repeats , Nitrogen Isotopes/metabolism , Salmonidae/anatomy & histology , Scotland
11.
Science ; 266(5184): 410-2, 1994 Oct 21.
Article in English | MEDLINE | ID: mdl-17816683

ABSTRACT

Observed sequences of large earthquakes are not consistent in either recurrence time or energy release; long-term prediction has been impossible even in areas, such as Parkfield, with well-defined recurrence intervals. The seismic gap hypothesis, which predicts characteristic earthquakes in areas of the circum-Pacific belt that have not produced recent great earthquakes, has also failed to predict the observed clustering of high-energy events. Models in which fractal scaling is broken at high magnitude predict that characteristic events and recurrence behavior will be unstable in time. The central predictions of these models are supported by recent observations at Landers and Big Bear in California.

12.
J Thromb Haemost ; 13(6): 1036-42, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25780857

ABSTRACT

BACKGROUND: Hemophilia A (HA) is an X-linked bleeding disorder caused by a deficiency in factor VIII (FVIII). von Willebrand disease (VWD) is characterized by a quantitative or qualitative defect in von Willebrand factor (VWF). Patients with VWD with severely low VWF or VWD Type 2N (VWD2N), a VWD subtype distinguished by defective VWF binding to FVIII, may have reduced FVIII levels secondary to their VWD. These patients superficially resemble patients with HA and pose a potential for misdiagnosis. OBJECTIVES: To investigate the unexplained cause of bleeding in HA patients without known FVIII mutations by assessing plasma VWF antigen (VWF:Ag), FVIII binding capacities and VWF genotypes. PATIENTS/METHODS: Thirty-seven of 1027 patients with HA studied as part of the Hemophilia Inhibitor Research Study lacked identifiable F8 mutations. These patients (cases) and 73 patients with identified F8 mutations (controls) were evaluated for VWF:Ag, a patient's VWF capacity to bind FVIII (VWF:FVIIIB) and VWF sequence. RESULTS: Four cases had VWF:Ag < 3 IU dL(-1) and VWF mutations consistent with Type 3 VWD. Six cases and one control were heterozygous for mutations previously reported to cause Type 1 VWD (VWD1) (n = five cases and one control) or predicted to be deleterious by Polyphen2 and SIFT prediction tools (n = 1 case). One control had VWF:Ag < 30 IU dL(-1) and seven patients (four cases and three controls), including two cases who were heterozygous for a known VWD2N mutation, had reduced VWF:FVIIIB. CONCLUSIONS: These data emphasize that some patients diagnosed with HA require VWF assessments in order to achieve a comprehensive diagnosis and an optimal treatment strategy.


Subject(s)
Blood Coagulation/genetics , Factor VIII/genetics , Hemophilia A/genetics , Mutation , von Willebrand Factor/genetics , Adolescent , Adult , Biomarkers/blood , Blood Coagulation Tests , Case-Control Studies , Child , DNA Mutational Analysis , Factor VIII/metabolism , Genetic Predisposition to Disease , Hemophilia A/blood , Hemophilia A/diagnosis , Hemorrhage/blood , Hemorrhage/diagnosis , Hemorrhage/genetics , Heterozygote , Homozygote , Humans , Male , Phenotype , Predictive Value of Tests , Protein Binding , United States , Young Adult , von Willebrand Factor/metabolism
13.
Neurology ; 25(8): 725-9, 1975 Aug.
Article in English | MEDLINE | ID: mdl-1171405

ABSTRACT

A 15-year-old girl died 14 days after hemiplegia suddenly developed. On arteriography, intimal separation of the middle cerebral arteries showed as a long attenuated column of dye--the "string" sign. Pathologic examination showed intimal separation starting at the distal bifurcation of the right internal carotid artery and extending into the middle and anterior cerebral arteries. The arteriographic string sign as evidence of dissection may aid diagnosis of this cause of childhood hemiplegia.


Subject(s)
Carotid Artery, Internal/abnormalities , Cerebrovascular Disorders/etiology , Adolescent , Carotid Arteries/diagnostic imaging , Cerebral Angiography , Cerebral Arteries/abnormalities , Cerebral Arteries/physiopathology , Cerebral Cortex/blood supply , Cerebral Hemorrhage/etiology , Female , Hemiplegia/etiology , Humans , Infarction
14.
J Immunol Methods ; 147(2): 251-9, 1992 Mar 04.
Article in English | MEDLINE | ID: mdl-1372335

ABSTRACT

We describe a new method of staining and quantification of proteins blotted or spotted on nitrocellulose. Blotted or spotted proteins are first reacted with specific antibodies followed by reaction with biotinylated secondary antibodies. The immunocomplex is then reacted with a streptavidin-based macromolecular complex labeled with the fluorescent europium chelate of 4,7-bis(chlorosulfophenyl) 1,10-phenanthroline-2,9-dicarboxylic acid (BCPDA). The fluorescent spots or bands can then be assessed by visual inspection under UV illumination, by instant photography or quantified by scanning with a time-resolved fluorometer. The method does not involve enzyme detection, is simple, sensitive and gives sharp bands which remain fluorescent for long periods of time (months to years).


Subject(s)
Blotting, Western/methods , Fluoroimmunoassay/methods , Proteins/analysis , Animals , Carcinoembryonic Antigen/analysis , Chelating Agents , Densitometry , Electrophoresis, Polyacrylamide Gel , Europium , Ferritins/analysis , Fluorescent Dyes , Humans , Phenanthrolines , alpha-Fetoproteins/analysis
15.
Am J Med Genet ; 25(2): 307-12, 1986 Oct.
Article in English | MEDLINE | ID: mdl-3777027

ABSTRACT

We report on an infant with a 69,XXY chromosome constitution who survived for 10 1/2 months; this is the longest survival reported with this condition to date. The infrequency of this disorder, data on natural history, and improved survival, possibly due to better management of respiratory illness and prematurity, are all factors worth noting in counseling on such rare conditions. Genotyping demonstrated the extra genome to be of maternal origin.


Subject(s)
Abnormalities, Multiple/genetics , Polyploidy , Humans , Infant , Longevity , Male
16.
Arch Surg ; 126(6): 711-3; discussion 713-4, 1991 Jun.
Article in English | MEDLINE | ID: mdl-2039358

ABSTRACT

Eleven patients with blunt chest trauma at risk for traumatic aortic rupture underwent transesophageal echocardiography to image the descending aorta. Diagnoses were compared with the results of radiographic studies. Ten of the 11 patients underwent arch aortography, with positive results in six cases. In one patient, the results of a computed tomographic scan were interpreted as consistent with aortic rupture. The results of transesophageal echocardiography were positive for ruptured descending aorta in three of six patients with positive aortographic findings, and negative in eight patients. All three patients with positive findings had the diagnosis of ruptured descending aorta confirmed at surgery. The remaining eight patients demonstrated no aortic morbidity. These preliminary findings suggest that transesophageal echocardiography is a useful technique for the diagnosis of ruptured descending aorta following blunt chest trauma.


Subject(s)
Aorta, Thoracic/injuries , Aortic Rupture/diagnostic imaging , Echocardiography/methods , Wounds, Nonpenetrating/complications , Adult , Aortic Rupture/etiology , Aortography , Female , Humans , Male , Thoracic Injuries/complications
17.
Thromb Res ; 81(1): 133-43, 1996 Jan 01.
Article in English | MEDLINE | ID: mdl-8747528

ABSTRACT

In this study, 176 healthy men and women between the ages of 18 and 25 yrs were tested for fibrinolytic activity before and after a 5 min period of venous occlusion (VO) at 100 mm Hg. Using this protocol, 140 demonstrated an increase in fibrin plate lysis following this brief period of venous occlusion and were classified as "Responders." There were 36 individuals in the study who showed either a decrease or no change in fibrin plate lysis after 5 min of venous occlusion and they were classified as "Non-Responders." Responders showed a decrease in PAI-1 following VO. However, neither Responders nor Non-Responders demonstrated any significant differences in the levels of plasminogen, antiplasmin, protein C, free t-PA, or total t-PA following this brief exposure to venous occlusion. When comparing women and men in this study, women had significantly greater fibrin plate lysis both before and after 5 min of VO. They also demonstrated higher pre- and post-VO levels of circulating plasminogen. Also, women had less PAI-1 pre- and post-VO than men. When examining Responders and Non-Responders according to gender, women who were Responders had significantly greater fibrin plate lysis before and after VO than male Responders. Also, women Responders demonstrated a significant decrease in PAI-1 following 5 min of VO when compared to men who were Responders in this study.


Subject(s)
Fibrinolysis , Veins/physiology , Adolescent , Adult , Blood Volume , Constriction , Female , Hematocrit , Humans , Male , Plasminogen/analysis , Plasminogen Activator Inhibitor 1/analysis , Protein C/analysis , Reference Values , Sex Characteristics , Tissue Plasminogen Activator/analysis , alpha-2-Antiplasmin/analysis
18.
Mutat Res ; 292(1): 3-16, 1993 Aug.
Article in English | MEDLINE | ID: mdl-7688095

ABSTRACT

Harvest time is one of the most important variables in the assessment of whether a compound is clastogenic and in establishing a dose relation. In CHO cells we have found that for a variety of chemicals one harvest time near 20 h is optimal following a 3-h treatment (Bean et al., 1992). However, some guidelines for testing for regulatory purposes recommend an additional late harvest time 24 h after the first. We tested 10 diverse chemicals in CHO-WBL cells harvested 20-21 h and 42-44 h from the beginning of a 3-hr treatment. We added BrdUrd after treatment and recorded the total% of aberrant cells, and the proportions of aberrations (abs) in first (M1), second (M2) or later metaphases. The chemicals fell into 3 categories: ab yield greatly decreased at 44 h: benzo[a]pyrene, cadmium sulfate, chlorambucil, 2,6-diaminotoluene, 4-nitroquinoline N-oxide and mitomycin C (e.g., 37.0% cells with abs at 20 h and 1.0% at 44 h); ab yields similar at 20 and 44 h: 2-aminobiphenyl, eugenol and 8-hydroxyquinoline (e.g., 8.5% at 20 h and 7.0% at 44 h); and one, dimethylnitrosamine (DMN), which was detected at both times but gave a stronger response at 44 h than at 20 h (e.g., at 10 mM: 6.2% at 20 h and 25.0% at 44 h). This DMN effect was not seen in normal diploid human cells. For DMN the higher ab levels at 44 h than at 20 h were contributed by abs in M3 cells. Thus, while for some chemicals ab yields decrease with successive division, further increases can be seen in CHO in later metaphases, notably for DMN. Overall, however, after a 3-h pulse treatment of CHO cells a positive ab result could be obtained at the early harvest time (20 h) for all 10 chemicals.


Subject(s)
Chromosome Aberrations , Mutagenicity Tests/methods , Animals , Biotransformation , Bromodeoxyuridine , CHO Cells , Cell Cycle , Cricetinae , Humans , Male , Mutagens/pharmacokinetics , Mutagens/toxicity , Rats , Rats, Sprague-Dawley , Time Factors
19.
Mutat Res ; 265(1): 31-44, 1992 Jan.
Article in English | MEDLINE | ID: mdl-1370241

ABSTRACT

Choice of harvest time is one of the most important variables in the assessment of whether a compound is clastogenic and in establishing a dose relation. We examined the effects of sampling time on aberration yield for 7 diverse chemicals in CHO-WBL cells by harvesting at intervals from 9 to 30 h after treatment for 3 h with or without S9 metabolic activation. We observed both the percentage of aberrant cells and the total number of aberrations. Our data suggest that for most compounds a single harvest time approximately 17-21 h after the beginning of a 3-h treatment is optimal for aberration detection in CHO cells. Maximal aberration yields were observed for 2,4-diaminotoluene, 2,6-diaminotoluene and cytosine beta-D-arabinofuranoside from 17 to 21 h, eugenol from 15 to 21 h, cadmium sulfate from 15 to 24 h and 2-aminobiphenyl, from 17 to 24 h. For adriamycin at 1 microM, the % aberrant cells remained elevated throughout the period from 9 to 29 h, while small increases at 0.1 microM ADR were found only at 13 and at 25 h. For most chemicals the maximal aberration yield occurred at a different time for each concentration tested. However, the use of 3 or more closely spaced concentrations, carefully selected to yield up to 50% toxicity, allowed detection of a positive response at a single harvest time for all 7 chemicals.


Subject(s)
Cadmium Compounds , Chromosome Aberrations , Mutagenicity Tests/methods , Mutagens/toxicity , Sulfates , Aminobiphenyl Compounds/toxicity , Animals , CHO Cells , Cadmium/toxicity , Cell Count , Cricetinae , Cytarabine/toxicity , Doxorubicin/toxicity , Eugenol/toxicity , Phenylenediamines/toxicity , Time Factors
20.
Mutat Res ; 265(1): 45-60, 1992 Jan.
Article in English | MEDLINE | ID: mdl-1370242

ABSTRACT

Regulatory guidelines suggest testing chemicals up to cytotoxic doses in chromosomal-aberration assays. To investigate the utility and limitations of various cytotoxicity indicators we used Chinese hamster ovary (CHO) cells to test 8 chemicals with differing ratios of cytotoxicity to clastogenicity. We measured immediate or delayed cell killing and growth inhibition (ATP levels, cell counts, colony-forming efficiency, CFE) and cell-cycle perturbations (mitotic index, MI; average generation time, AGT). Aberrations (abs) were scored 10 and 24 h from the beginning of the 3-h treatment. All 8 compounds induced abs at concentrations that reduced cell growth at 24 h by 50% or less. Concentrations of each chemical which induced at least 15% cells with abs, gave little loss of CFE (0-20%) for mitomycin C, adriamycin, cadmium sulfate and 2,6-diaminotoluene in contrast to the marked loss of CFE (70-80%) for eugenol (EUG), 2-aminobiphenyl and 8-hydroxyquinoline (8-HQ). 2,4-Diaminotoluene (2,4-DAT) was intermediate. Higher aberration yields were found at 24 h than at 10 h, even when minimal cell-cycle delay was detected by AGT estimates from BrdUrd-labeled cells. Cells with multiple abs were seen at 24 but not at 10 h, and often confirmed clastogenicity when there was only a weak increase in the percentage of cells with aberrations. Total ATP per culture did not always correlate with cell number, especially at later times after treatment. This is likely due to metabolic perturbations or altered cell biomass that are known to affect cell ATP content. MI suppression often did not correlate with AGT, e.g., only small increases in AGT were seen for 8-HQ, 2,4-DAT and EUG despite severe mitotic suppression at 10 h. By 24 h the MI for all chemicals had recovered, sometimes exceeding control levels. Marked mitotic accumulation was seen at 10 h for 2,4-DAT, indicating cell synchrony. Thus, the MI has limited value for dose selection. In conclusion, even weakly active chemicals were detected at a single time without exceeding a 50% growth reduction at 24 h.


Subject(s)
Cadmium Compounds , Chromosome Aberrations , Mutagenicity Tests/methods , Mutagens/toxicity , Sulfates , Aminobiphenyl Compounds/toxicity , Animals , CHO Cells , Cadmium/toxicity , Cricetinae , Doxorubicin/toxicity , Eugenol/toxicity , Evaluation Studies as Topic , Mitomycin/toxicity , Oxyquinoline/toxicity , Phenylenediamines/toxicity , Time Factors
SELECTION OF CITATIONS
SEARCH DETAIL