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1.
Parasitol Res ; 116(6): 1755-1760, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28484854

RESUMO

We present data on the species composition of helminths in brown bears (Ursus arctos) from the Murmansk Region, Russia. The absence of any information about helminths of brown bear in the region necessitated the conduct of these studies. Samples were collected in 2014 and 2015 in the southern part of the Kola Peninsula from the White Sea coastal habitats. Annually, in the study area, 1-3 bears are legally hunted and biological samples for examination are very difficult to obtain. Therefore, we used fecal samples. We studied 93 feces and identified parasite eggs identified in 43 of them by morphometric criteria. The surveys revealed eggs of the following helminths: Dicrocoelium sp., Diphyllobothrium sp., Anoplocephalidae, Capillariidae, Baylisascaris sp., Strongylida 1, and Strongylida 2. These results represent the first reconnaissance stage, which allowed characterizing the taxonomic diversity and prevalence of parasites of brown bears of the Kola Peninsula.


Assuntos
Helmintíase Animal/parasitologia , Helmintos/isolamento & purificação , Ursidae/parasitologia , Animais , Fezes , Helmintíase Animal/epidemiologia , Helmintos/classificação , Federação Russa/epidemiologia
2.
Bull Entomol Res ; 107(2): 241-250, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27876095

RESUMO

The European winter moth, Operophtera brumata, is a non-native pest in the Northeastern USA causing defoliation of forest trees and crops such as apples and blueberries. This species is known to hybridize with O. bruceata, the Bruce spanworm, a native species across North America, although it is not known if there are hybrid generations beyond F1. To study winter moth population genetics and hybridization with Bruce spanworm, we developed two sets of genetic markers, single nucleotide polymorphisms (SNPs) and microsatellites, using genomic approaches. Both types of markers were validated using samples from the two species and their hybrids. We identified 1216 SNPs and 24 variable microsatellite loci. From them we developed a subset of 95 species-diagnostic SNPs and ten microsatellite loci that could be used for hybrid identification. We further validated the ten microsatellite loci by screening field collected samples of both species and putative hybrids. In addition to confirming the presence of F1 hybrids reported in previous studies, we found evidence for multi-generation asymmetric hybridization, as suggested by the occurrence of hybrid backcrosses with the winter month, but not with the Bruce spanworm. Laboratory crosses between winter moth females and Bruce spanworm males resulted in a higher proportion of viable eggs than the reciprocal cross, supporting this pattern. We discuss the possible roles of population demographics, sex chromosome genetic incompatibility, and bacterial symbionts as causes of this asymmetrical hybridization and the utility of the developed markers for future studies.


Assuntos
Hibridização Genética , Repetições de Microssatélites , Mariposas/genética , Polimorfismo de Nucleotídeo Único , Animais , Marcadores Genéticos , Espécies Introduzidas , Mid-Atlantic Region , New England , Análise de Sequência de DNA
3.
Forensic Sci Int Genet ; 6(6): 798-809, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22483764

RESUMO

A set of 13 dinucleotide STR loci (G1A, G10B, G1D, G10L, MU05, MU09, MU10, MU15, MU23, MU26, MU50, MU51, MU59) were selected as candidate markers for a DNA forensic profiling system for Northern European brown bear (Ursus arctos). We present results from validation of the markers with respect to their sensitivity, species specificity and performance (precision, heterozygote balance and stutter ratios). All STRs were amplified with 0.6ng template input, and there were no false bear genotypes in the cross-species amplification tests. The validation experiments showed that stutter ratios and heterozygote balance was more pronounced than in the tetranucleotide loci used in human forensics. The elevated ratios of stutter and heterozygote balance at the loci validated indicate that these dinucleotide STRs are not well suited for interpretation of individual genotypes in mixtures. Based on the results from the experimental validations we discuss the challenges related to genotyping dinucleotide STRs in single source samples. Sequence studies of common alleles showed that, in general, the size variation of alleles corresponded with the variation in number of repeats. The samples characterized by sequence analysis may serve as standard DNA samples for inter laboratory calibration. A total of 479 individuals from eight Northern European brown bear populations were analyzed in the 13 candidate STRs. Locus MU26 was excluded as a putative forensic marker after revealing large deviations from expected heterozygosity likely to be caused by null-alleles at this locus. The remaining STRs did not reveal significant deviations from Hardy-Weinberg equilibrium expectations except for loci G10B and MU10 that showed significant deviations in one population each, respectively. There were 9 pairwise locus comparisons that showed significant deviation from linkage equilibrium in one or two out of the eight populations. Substantial genetic differentiation was detected in some of the pairwise population comparisons and the average estimate of population substructure (F(ST)) was 0.09. The average estimate of inbreeding (F(IS)) was 0.005. Accounting for population substructure and inbreeding the total average probability of identity in each of the eight populations was lower than 1.1×10(-9) and the total average probability of sibling identity was lower than 1.3×10(-4). The magnitude of these measurements indicates that if applying these twelve STRs in a DNA profiling system this would provide individual specific evidence.


Assuntos
Impressões Digitais de DNA/métodos , Repetições de Microssatélites , Ursidae/genética , Alelos , Animais , Conservação dos Recursos Naturais , Primers do DNA , Bases de Dados de Ácidos Nucleicos , Europa (Continente) , Loci Gênicos , Marcadores Genéticos , Heterozigoto , Desequilíbrio de Ligação , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Especificidade da Espécie
4.
Bull Entomol Res ; 101(6): 705-14, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21729393

RESUMO

Population cycles of the winter moth (Operophtera brumata) in sub-arctic coastal birch forests show high spatiotemporal variation in amplitude. Peak larval densities range from levels causing little foliage damage to outbreaks causing spatially extensive defoliation. Moreover, outbreaks typically occur at or near the altitudinal treeline. It has been hypothesized that spatiotemporal variation in O. brumata cycle amplitude results from climate-induced variation in the degree of phenological matching between trophic levels, possibly between moth larvae and parasitoids. The likelihood of mismatching phenologies between larvae and parasitoids is expected to depend on how specialized parasitoids are, both as individual species and as a guild, to attacking specific larval developmental stages (i.e. instars). To investigate the larval instar-specificity of parasitoids, we studied the timing of parasitoid attacks relative to larval phenology. We employed an observational study design, with sequential sampling over the larval period, along an altitudinal gradient harbouring a pronounced treeline outbreak of O. brumata. Within the larval parasitoid guild, containing seven species groups, the timing of attack by different groups followed a successional sequence throughout the moth's larval period and each group attacked 1-2 instars. Such phenological diversity within parasitoid guilds may lower the likelihood of climate-induced trophic mismatches between victim populations and many/all of their enemies. Parasitism rates declined with increasing altitude for most parasitoid groups and for the parasitoid guild as a whole. However, the observed spatiotemporal parasitism patterns provided no clear evidence for or against altitudinal mismatch between larval and parasitoid phenology.


Assuntos
Clima , Ecossistema , Interações Hospedeiro-Parasita , Mariposas/parasitologia , Vespas/fisiologia , Altitude , Animais , Betula , Larva/parasitologia , Modelos Logísticos , Noruega , Fatores de Tempo
5.
Chemosphere ; 45(4-5): 653-8, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11680761

RESUMO

In this study, we compared the sensitivity of freshwater and marine organisms to two structurally similar substances, acrylic acid and methacrylic acid. Reported acute toxicity data (L(E)C50-values) for freshwater organisms range from 0.1 to 222 mg/l and 85 to >130 mg/l for acrylic acid and methacrylic acid, respectively. The large variation in toxicity data for acrylic acid is due to a specific toxicity to certain species of freshwater microalgae, with algae EC50-values being two to three orders of magnitude lower than L(E)C50-values reported for fish and invertebrates. To evaluate the sensitivity of marine organisms, ecotoxicity data was generated for ten species of microalgae, one invertebrate species and one fish species. For methacrylic acid, we found a marine acute toxicity that ranged from 110 to >1260 mg/l, which is comparable to reported data on freshwater organisms. In strong contrast, the resulting L(E)C50-values for acrylic acid ranged from 50 to >1000 mg/l, and there was no specific sensitivity of marine algae when compared to marine invertebrates and fish. For acrylic acid, therefore, use of the available freshwater toxicity data for an effects assessment for the marine environment is likely to overestimate the hazard and risk from this substance. Overall, the results of the study suggest that ecotoxicity data generated on freshwater species may not always be appropriate for the effects assessments of organic chemicals in the marine environment, thus emphasising the importance of using ecologically relevant data to assess environmental risk.


Assuntos
Acrilatos/toxicidade , Eucariotos , Metacrilatos/toxicidade , Adesivos Teciduais/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores , Crustáceos , Ecossistema , Linguados , Previsões , Dose Letal Mediana , Medição de Risco
6.
Aust N Z J Ophthalmol ; 26(1): 43-6, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9524030

RESUMO

PURPOSE: To describe the ocular anomalies in two cases of branchio-oculo-facial syndrome (BOFS). METHODS: Two cases of BOFS are reviewed. RESULTS/CONCLUSIONS: Branchio-oculo-facial syndrome is a rare branchial cleft syndrome that is characterized by a typical facial appearance of pseudo-cleft or cleft lip, subauricular branchial sinuses, deafness and ocular anomalies, which include nasolacrimal obstruction, telecanthus and colobomata. It has an autosomal dominant inheritance pattern.


Assuntos
Síndrome Brânquio-Otorrenal/complicações , Anormalidades do Olho/complicações , Síndrome Brânquio-Otorrenal/diagnóstico , Síndrome Brânquio-Otorrenal/genética , Dacriocistorinostomia , Anormalidades do Olho/diagnóstico , Anormalidades do Olho/genética , Seguimentos , Humanos , Lactente , Obstrução dos Ductos Lacrimais/diagnóstico , Obstrução dos Ductos Lacrimais/etiologia , Masculino
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