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1.
Sci Justice ; 60(1): 95-98, 2020 01.
Article in English | MEDLINE | ID: mdl-31924295

ABSTRACT

There is a recognized disconnect in priority and synergy between academic and practitioners in forensic science. In this work, we personally reflect on our experiences in conducting research studies that directly involve academic and practitioner stakeholders. We believe, amongst others, that this "gap" can be mitigated through regular and productive communication. We also emphasize the need to create stronger and national research strategies which identifies the current and pressing needs of enforcement officials in order to bring these needs directly to academia. As part of this, researchers should actively seek to make sure what they study will be relevant within the discipline. Our reflection is geared on direct feedback from an entomological study in large scale sampling of blowflies and workshops in bloodstain pattern analysis using a forensic blood substitute.


Subject(s)
Forensic Sciences , Research Design , Stakeholder Participation/psychology , Blood Stains , Canada , Forensic Entomology , Humans
2.
Forensic Sci Int ; 240: 122-5, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24815994

ABSTRACT

Forensic entomology involves the use of insects and arthropods to assist a spectrum of medico-criminal investigations that range from identifying cases of abuse, corpse movements, and most commonly, post mortem interval estimates. Many of these applications focus on the use of blowflies given their predicable life history characteristics in their larval stages. Molecular tools have become increasingly important in the unambiguous identification of larval blowfly species, however, these same tools have the potential to broaden the array of molecular applications in forensic entomology to include individual identifications and population assignments. Herein, we establish a microsatellite profiling system for the blowfly, Phormiaregina (Diptera: Calliphoridae). The goal being to create a system to identify the population genetic structure of this species and subsequently establish if these data are amenable to identifying corpse movements based on the geographic distribution of specific genetic clusters of blowflies. Using next generation sequencing technology, we screened a partial genomic DNA sequence library of P.regina, searching for di-, tetra-, and penta-nucleotide microsatellite loci. We identified and developed primers for 84 highly repetitive segments of DNA, of which 14 revealed consistent genotypes and reasonable levels of genetic variation (4-26 alleles/locus; heterozygosity ranged from 0.385 to 0.909). This study provides the first step in assessing the utility of microsatellite markers to track the movements and sources of corpses via blowflies.


Subject(s)
DNA Fingerprinting/methods , Diptera/genetics , Microsatellite Repeats , Animals , DNA Primers , Sequence Analysis, DNA/methods
3.
Vaccine ; 31(17): 2207-13, 2013 Apr 19.
Article in English | MEDLINE | ID: mdl-23499602

ABSTRACT

ONRAB is a rabies glycoprotein recombinant human adenovirus type 5 oral vaccine developed for application in baits to control rabies in wildlife populations. Prior to widespread use of ONRAB, both the safety and effectiveness of this vaccine required investigation. While previous research has focused on field performance and the persistence and pathogenicity of ONRAB in captive animals, we sought to examine persistence and shedding of ONRAB in populations of free-ranging target and non-target mammals. We collected oral and rectal swab samples from 84 red foxes, 169 striped skunks, and 116 raccoons during 2007 and 2008 in areas where ONRAB vaccine baits were distributed. We also analyzed 930 tissue samples, 135 oral swab and 138 rectal swab samples from 155 non-target small mammals from 10 species captured during 2008 at sites treated with high densities of ONRAB vaccine baits. Samples were screened for the presence and quantity of ONRAB DNA using quantitative real-time PCR. None of the samples that we analyzed from target and non-target species contained quantities of ONRAB greater than 10(3)EU/mL of ONRAB DNA which is a limit that has previously been applied to assess viral shedding. This study builds on similar research and suggests that replication of ONRAB in animals is short-lived and the likelihood of horizontal transmission to other organisms is low.


Subject(s)
Mammals/immunology , Rabies Vaccines/administration & dosage , Rabies Vaccines/immunology , Rabies/immunology , Administration, Oral , Animals , Antibodies, Viral/immunology , Humans , Ontario , Rabies/prevention & control , Rabies Vaccines/adverse effects , Rabies Vaccines/genetics , Rabies virus/genetics , Rabies virus/immunology , Rabies virus/isolation & purification , Rabies virus/physiology , Real-Time Polymerase Chain Reaction , Vaccines, DNA/administration & dosage , Vaccines, DNA/adverse effects , Vaccines, DNA/genetics , Vaccines, DNA/immunology , Vaccines, Synthetic/administration & dosage , Vaccines, Synthetic/adverse effects , Vaccines, Synthetic/genetics , Vaccines, Synthetic/immunology , Virus Shedding
4.
Mol Ecol ; 17(22): 4874-86, 2008 Nov.
Article in English | MEDLINE | ID: mdl-19140978

ABSTRACT

Epidemiological models are useful tools for management to predict and control wildlife disease outbreaks. Dispersal behaviours of the vector are critical in determining patterns of disease spread, and key variables in epidemiological models, yet they are difficult to measure. Raccoon rabies is enzootic over the eastern seaboard of North America and management actions to control its spread are costly. Understanding dispersal behaviours of raccoons can contribute to refining management protocols to reduce economic impacts. Here, estimates of dispersal were obtained through parentage and spatial genetic analyses of raccoons in two areas at the front of the raccoon rabies epizootic in Ontario; Niagara (N = 296) and St Lawrence (N = 593). Parentage analysis indicated the dispersal distance distribution is highly positively skewed with 85% of raccoons, both male and female, moving < 3 km. The tail of this distribution indicated a small proportion (< 4%) moves more than 20 km. Analysis of spatial genetic structure provided a similar assessment as the spatial genetic correlation coefficient dropped sharply after 1 km. Directionality of dispersal would have important implications for control actions; however, evidence of directional bias was not found. Separating the data into age and sex classes the spatial genetic analyses detected female philopatry. Dispersal distances differed significantly between juveniles and adults, while juveniles in the Niagara region were significantly more related to each other than adults were to each other. Factors that may contribute to these differences include kin association, and spring dispersal. Changes to the timing and area covered by rabies control operations in Ontario are indicated based on these dispersal data.


Subject(s)
Disease Outbreaks/veterinary , Genetics, Population , Rabies/veterinary , Raccoons/genetics , Alleles , Animals , Animals, Wild/genetics , Animals, Wild/virology , Behavior, Animal , Disease Outbreaks/prevention & control , Ecosystem , Female , Genotype , Geography , Locomotion , Male , Microsatellite Repeats , Molecular Epidemiology , Ontario/epidemiology , Rabies/epidemiology , Rabies/prevention & control , Raccoons/virology
5.
Mol Ecol ; 16(6): 1245-55, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17391410

ABSTRACT

Mate-choice theory predicts different optimal mating systems depending on resource availability and habitat stability. Regions with limited resources are thought to promote monogamy. We tested predictions of monogamy in a social rodent, the hoary marmot (Marmota caligata), at the northern climatic extreme of its distribution. Mating systems, social structure and genetic relationships were investigated within and among neighbouring colonies of marmots within a 4 km(2) valley near Kluane National Park, Yukon, Canada, using 21 microsatellite loci. While both monogamous and polygynous populations of hoary marmots have been observed in the southern reaches of this species' range; northern populations of this species are thought to be predominantly monogamous. Contrary to previous studies, we did not find northern hoary marmot social groups to be predominantly monogamous; rather, the mating system seemed to be facultative, varying between monogamy and polygyny within, as well as among, social groups. These findings reveal that the mating systems within colonies of this species are more flexible than previously thought, potentially reflecting local variation in resource availability.


Subject(s)
Climate , Ecosystem , Genetics, Population , Marmota/physiology , Sexual Behavior, Animal/physiology , Animals , Marmota/genetics , Microsatellite Repeats/genetics , Observation , Yukon Territory
6.
Forensic Sci Int ; 166(1): 68-76, 2007 Feb 14.
Article in English | MEDLINE | ID: mdl-16690237

ABSTRACT

The use of DNA in forensics has grown rapidly for human applications along with the concomitant development of bioinformatics and demographic databases to help fully realize the potential of this molecular information. Similar techniques are also used routinely in many wildlife cases, such as species identification in food products, poaching and the illegal trade of endangered species. The use of molecular techniques in forensic cases related to wildlife and the development of associated databases has, however, mainly focused on large mammals with the exception of a few high-profile species. There is a need to develop similar databases for aquatic species for fisheries enforcement, given the large number of exploited and endangered fish species, the intensity of exploitation, and challenges in identifying species and their derived products. We sequenced a 500bp fragment of the mitochondrial cytochrome b gene from representative individuals from 26 harvested fish taxa from Ontario, Canada, focusing on species that support major commercial and recreational fisheries. Ontario provides a unique model system for the development of a fish species database, as the province contains an evolutionarily diverse array of freshwater fish families representing more than one third of all freshwater fish in Canada. Inter- and intraspecific sequence comparisons using phylogenetic analysis and a BLAST search algorithm provided rigorous statistical metrics for species identification. This methodology and these data will aid in fisheries enforcement, providing a tool to easily and accurately identify fish species in enforcement investigations that would have otherwise been difficult or impossible to pursue.


Subject(s)
DNA, Mitochondrial/analysis , Fishes/genetics , Animals , Extinction, Biological , Fishes/classification , Forensic Pathology , Fresh Water , Ontario
7.
Mol Ecol ; 10(9): 2341-7, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11555275

ABSTRACT

Fishers are mid-sized forest carnivores indigenous to North America that experienced sharp population declines from the early 1800s through to the mid-1900s. To evaluate levels of genetic variation within and subdivision among northern fisher populations 459 individuals were genotyped using 13 microsatellite loci. Genetic diversity was found to be slightly lower in re-introduced populations than in adjacent indigenous populations. Furthermore, fisher populations revealed much more genetic structuring than two closely related mustelids. Further investigation is needed to determine if fishers are more philopatric than martens and wolverines or if barriers to dispersal explain the levels of structure identified in this study.


Subject(s)
Carnivora/genetics , Genetic Variation , Animals , Microsatellite Repeats/genetics , North America
8.
Mol Ecol ; 10(2): 337-47, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11298949

ABSTRACT

Wolverines (Gulo gulo) are found in low densities throughout their circumpolar distribution. They are also potentially susceptible to human-caused population fragmentation (development, recreation and fur harvesting). The combination of these factors has contributed to this species being listed as having either vulnerable or endangered status across much of its current range. The effects of inherently low densities and anthropogenic pressures on the genetic structure and variation of wolverine populations are, as yet, unknown. In this study, 461 individuals were typed at 12 microsatellite loci to investigate the population genetic structure of wolverines from north-western Alaska to eastern Manitoba. Levels of gene flow and population differentiation among the sampled regions were estimated via a genotype assignment test, pairwise F(ST), and two genetic distance measures. Our results suggest that wolverine populations from southernmost regions, in which anthropogenic factors are strongest, revealed more genetic structuring than did northern populations. Furthermore, these results suggest that reductions in this species' range may have led to population fragmentation in the extreme reaches of its southern distribution. The continued reduction of suitable habitat for this species may lead to more populations becoming isolated remnants of a larger distribution of northern wolverines, as documented in other North American carnivore species.


Subject(s)
Carnivora/genetics , Animals , DNA/analysis , Data Interpretation, Statistical , Female , Genetics, Population , Humans , Male , Microsatellite Repeats/genetics , North America , Phylogeny
9.
Proc Biol Sci ; 265(1393): 303-8, 1998 Feb 22.
Article in English | MEDLINE | ID: mdl-9523433

ABSTRACT

Littorina subrotundata from wave-exposed rocky shores differ consistently in shell and radula morphology from those found in wave-protected salt-marshes. To determine if the two morphological forms of this gastropod represent separate species, clades, or ecotypes, DNA sequencing and single-stranded conformational polymorphism (SSCP) analysis were used to assay variation in a 480 bp fragment of the mitochondrial cytochrome-b gene. Several nested analyses of molecular variance (AMOVA) were then performed to test if grouping populations by geographical region or habitat type better explained the distribution of cytochrome-b haplotypes among some northeastern Pacific populations. The analysis by geographic region resulted in a significant variance component that explained 53% of the variance, whereas the analysis by habitat type was not significant. These results, along with previous studies showing that the differences in shell morphology among different forms have a heritable component, suggest that the two forms are ecotypes and not separate species or clades as had been previously proposed. These results also imply that each ecotype has evolved independently in each geographic area and that the morphological similarity of individuals from the same habitat type is most likely the result of parallel evolution.


Subject(s)
DNA/analysis , Evolution, Molecular , Mollusca/genetics , Analysis of Variance , Animals , DNA/genetics , Polymerase Chain Reaction
10.
Depress Anxiety ; 8(4): 147-53, 1998.
Article in English | MEDLINE | ID: mdl-9871816

ABSTRACT

The enhanced sensitivity of the elderly to the side effects produced by tricyclic antidepressants (TCAs), and the frequency and type of adverse events, have made the treatment of depression in this group difficult. The selective serotonin reuptake inhibitors (SSRIs) have been reported to produce significantly fewer undesirable side effects and display better tolerance than TCAs. We compared the therapeutic actions and side effects produced by citalopram, the most selective SSRI available, with amitriptyline in a group of elderly patients (aged 65 and older) diagnosed with major depression. In a double-blind, double-dummy, parallel-group, multicenter comparison of citalopram (20 or 40 mg/day) and amitriptyline (50 or 100 mg/day), patients who did not respond to placebo during a 1-week single-blind phase were randomly assigned to receive citalopram or amitriptyline for 8 weeks. Efficacy measures included the Montgomery-Asberg Depression Rating Scale (MADRS), the Hamilton Depression Scale (HAMD), and Clinical Global Impressions. Both drug treatments produced equivalent time-related declines in severity of depression, so that by 8 weeks slightly more than 50% of the patients in each group experienced marked recovery, defined as MADRS scores < or = 12. Amitriptyline produced a greater overall incidence of adverse events, including a significantly higher (P < 0.001) percentage of patients reporting dry mouth (34% vs. 7%), as well as a significantly higher (P < 0.02) incidence of somnolence. Constipation and fatigue also occurred more frequently in the amitriptyline than in the citalopram group. For only one event (nausea) did the citalopram group report a significantly greater (P = 0.012) incidence (12.8% vs. 4.8%). On the basis of these results, it was concluded that citalopram is as effective an antidepressant as amitriptyline in the treatment of the depressed elderly. Because of its low incidence and low magnitude of side effects, citalopram seems especially useful in private practice.


Subject(s)
Amitriptyline/therapeutic use , Citalopram/therapeutic use , Depressive Disorder/drug therapy , Selective Serotonin Reuptake Inhibitors/therapeutic use , Aged , Amitriptyline/adverse effects , Citalopram/adverse effects , Double-Blind Method , Female , Humans , Male , Primary Health Care , Selective Serotonin Reuptake Inhibitors/adverse effects
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