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Serge Utevsky - One of the best experts on this subject based on the ideXlab platform.
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Entrapped by the uneven central and Middle Eastern terrains: Genetic status of populations of Hirudo orientalis (Annelida, Clitellata, Hirudinida) with a phylogenetic review of the genus Hirudo.
Molecular Phylogenetics and Evolution, 2018Co-Authors: Kaveh Darabi-darestani, Alireza Sari, Alimorad Sarafrazi, Serge UtevskyAbstract:Phylogenetic relationships between species of the genus Hirudo plus genetic variation in the entire distribution range of Hirudo orientalis were investigated based on mitochondrial (COI and 12S rDNA) and nuclear (ITS1+5.8S+ITS2) genome regions. The sister relationship of Hirudo orientalis and H. medicinalis was revealed with a high posterior probability. A broad and patchy distribution with minor genetic differences was observed in populations of H. orientalis along the central and Middle Eastern parts of Asia. The known distribution range occurred in topographically heterogeneous landscapes around the Caspian Sea. The demographic analysis suggests the selection of the COI locus under unfavourable respiratory conditions, but population size expansion cannot be fully rejected. The genetic variation trend indicated northward dispersal. Higher haplotype diversity in the South Caspian region potentially suggests the area as a historical refugium for the species. The vast dispersal is assumed to occur after the Pleistocene glaciations via vertebrate hosts.
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Phylogeny and phylogeography of medicinal leeches (genus Hirudo): Fast dispersal and shallow genetic structure
Molecular Phylogenetics and Evolution, 2012Co-Authors: Peter Trontelj, Serge UtevskyAbstract:Medicinal leeches (Hirudo spp.) are among the best-studied invertebrates in many aspects of their biology. Yet, relatively little is known about their biogeography, ecology and evolution. Previous studies found vast ranges but suggested low genetic diversity for some species. To examine this apparent contradiction, the phylogeny and phylogeography of the widespread Hirudo verbana, Hirudo medicinalis and Hirudo orientalis were investigated in a comparative manner. Populations from across their ranges in Europe, Asia Minor, the Caucasus and Central Asia, were analyzed by various phylogenetic and population genetic approaches using both mitochondrial (COI and 12S) and nuclear DNA sequences (ITS1, 5.8S and ITS2). The populations showed surprisingly little genetic differentiation despite vast ranges. The only clear structure was observed in H. verbana. This species is subdivided into an Eastern (southern Ukraine, North Caucasus, Turkey and Uzbekistan) and a Western phylogroup (Balkans and Italy). The two phylogroups do not overlap, suggesting distinct postglacial colonization from separate refugia. Leeches supplied by commercial facilities belong to the Eastern phylogroup of H. verbana; they originate from Turkey and the Krasnodar Territory in Russia, two leading areas of leech export. H. verbana and H. medicinalis have experienced recent rapid population growth and range expansion, while isolation by distance has shaped the genetic setup of H. orientalis. The habitat of the latter is patchy and scattered about inhospitable arid and alpine areas of Central Asia and Transcaucasia. Centuries of leech collecting and transport across Europe seem not to have affected the natural distribution of genetic diversity, as the observed patterns can be explained by a combination of historical factors and present day climatic influences.
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Reproductive biology and ecological strategies of three species of medicinal leeches (genus Hirudo)
Journal of Natural History, 2011Co-Authors: Laima Petrauskienė, Olga Utevska, Serge UtevskyAbstract:An analysis of the reproduction of three species of medicinal leeches (genus Hirudo) was carried out. The highest fecundity (34.34 ± 3.72 hatchlings per leech) was observed in H. verbana, the lowest in H. medicinalis (11.10 ± 2.56). The heaviest hatchlings were found in H. medicinalis (0.046 ± 0.0005 g), the lightest in H. verbana (0.032 ± 0.0003 g). Hirudo orientalis had an intermediate fecundity (21.63 ± 3.39 hatchlings per leech) and its hatchlings were of intermediate weight (0.038 ± 0.0005 g). The species differ in their growth rate and mortality: Hirudo verbana had the smallest hatchlings and the lowest survivorship but its growth rate was highest among the three species. The results agree with sister relationships between H. medicinalis and H. orientalis and the basal position of H. verbana with respect to them. The reproductive traits of the three species suggest that H. verbana is an r-strategist that inhabits unstable environments, such as temporary ponds in steppe landscapes, whereas its congen...
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Distribution and status of medicinal leeches (genus Hirudo) in the Western Palaearctic: anthropogenic, ecological, or historical effects?
Aquatic Conservation: Marine and Freshwater Ecosystems, 2010Co-Authors: Serge Utevsky, Olga Utevska, Maja Zagmajster, Andrei Atemasov, Oleksandr Zinenko, Andrei Utevsky, Peter TronteljAbstract:1. Distribution and status of medicinal leeches were re-considered in the light of the new taxonomy recognizing four Western Palaearctic species: Hirudo medicinalis, Hirudo verbana, Hirudo orientalis and Hirudo troctina. 2. Recent records and new data obtained on expeditions to Ukraine, Russia, Azerbaijan, Kazakhstan, Uzbekistan and the Western Balkans were mapped to obtain an up-to-date overview of the distribution. 3. Three hypotheses explaining the current ranges of all Hirudo species were tested. The ecological hypothesis, suggesting a strong impact of large-scale environmental factors, received the highest support, while anthropogenic influence was minimal, and no historical patterns of refugia and colonization were detected. 4. Mapped localities of all Hirudo species show extensive, belt-shaped ranges extending from east to west. H. medicinalis is distributed from Britain and southern Norway to the southern Urals and probably as far as the Altai Mountains, occupying the deciduous arboreal zone. H. verbana has been recorded from Switzerland and Italy to Turkey and Uzbekistan, which largely corresponds to the Mediterranean and sub-boreal steppe zone. H. orientalis is associated with mountainous areas in the sub-boreal eremial zone and occurs in Transcaucasian countries, Iran and Central Asia. H. troctina has been found in north-western Africa and Spain in the Mediterranean zone. 5. Based on the data gathered, and considering real and potential threats, global IUCN category Near Threatened is proposed for H. medicinalis, H. verbana, and H. orientalis, while H. troctina can only be assigned to category Data Deficient. Copyright © 2010 John Wiley & Sons, Ltd.
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Can different species of medicinal leeches (Hirudo spp.) interbreed
Invertebrate Biology, 2009Co-Authors: Laima Petrauskienė, Olga Utevska, Serge UtevskyAbstract:. Since the 18th century, the medicinal leech Hirudo medicinalis has been thought to comprise a single species with several different color morphs, but recently some of these color morphs have been assigned to separate species based on morphology, geographical distribution, and molecular sequence data. This research was aimed at testing the ability of three of these species, H. medicinalis, Hirudo verbana, and Hirudo orientalis, to interbreed. We found that in the laboratory, all three species were able to mate with each other and produce hybrid offspring. This suggests that the reproductive isolation is not strong among these species of the genus Hirudo. However, fewer offspring were produced from interspecific crosses compared with intraspecific crosses. This decrease of fecundity (and in some cases, offspring viability) indicates some degree of reproductive isolation between H. medicinalis, H. verbana, and H. orientalis.
Peter Trontelj - One of the best experts on this subject based on the ideXlab platform.
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Phylogeny and phylogeography of medicinal leeches (genus Hirudo): Fast dispersal and shallow genetic structure
Molecular Phylogenetics and Evolution, 2012Co-Authors: Peter Trontelj, Serge UtevskyAbstract:Medicinal leeches (Hirudo spp.) are among the best-studied invertebrates in many aspects of their biology. Yet, relatively little is known about their biogeography, ecology and evolution. Previous studies found vast ranges but suggested low genetic diversity for some species. To examine this apparent contradiction, the phylogeny and phylogeography of the widespread Hirudo verbana, Hirudo medicinalis and Hirudo orientalis were investigated in a comparative manner. Populations from across their ranges in Europe, Asia Minor, the Caucasus and Central Asia, were analyzed by various phylogenetic and population genetic approaches using both mitochondrial (COI and 12S) and nuclear DNA sequences (ITS1, 5.8S and ITS2). The populations showed surprisingly little genetic differentiation despite vast ranges. The only clear structure was observed in H. verbana. This species is subdivided into an Eastern (southern Ukraine, North Caucasus, Turkey and Uzbekistan) and a Western phylogroup (Balkans and Italy). The two phylogroups do not overlap, suggesting distinct postglacial colonization from separate refugia. Leeches supplied by commercial facilities belong to the Eastern phylogroup of H. verbana; they originate from Turkey and the Krasnodar Territory in Russia, two leading areas of leech export. H. verbana and H. medicinalis have experienced recent rapid population growth and range expansion, while isolation by distance has shaped the genetic setup of H. orientalis. The habitat of the latter is patchy and scattered about inhospitable arid and alpine areas of Central Asia and Transcaucasia. Centuries of leech collecting and transport across Europe seem not to have affected the natural distribution of genetic diversity, as the observed patterns can be explained by a combination of historical factors and present day climatic influences.
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Distribution and status of medicinal leeches (genus Hirudo) in the Western Palaearctic: anthropogenic, ecological, or historical effects?
Aquatic Conservation: Marine and Freshwater Ecosystems, 2010Co-Authors: Serge Utevsky, Olga Utevska, Maja Zagmajster, Andrei Atemasov, Oleksandr Zinenko, Andrei Utevsky, Peter TronteljAbstract:1. Distribution and status of medicinal leeches were re-considered in the light of the new taxonomy recognizing four Western Palaearctic species: Hirudo medicinalis, Hirudo verbana, Hirudo orientalis and Hirudo troctina. 2. Recent records and new data obtained on expeditions to Ukraine, Russia, Azerbaijan, Kazakhstan, Uzbekistan and the Western Balkans were mapped to obtain an up-to-date overview of the distribution. 3. Three hypotheses explaining the current ranges of all Hirudo species were tested. The ecological hypothesis, suggesting a strong impact of large-scale environmental factors, received the highest support, while anthropogenic influence was minimal, and no historical patterns of refugia and colonization were detected. 4. Mapped localities of all Hirudo species show extensive, belt-shaped ranges extending from east to west. H. medicinalis is distributed from Britain and southern Norway to the southern Urals and probably as far as the Altai Mountains, occupying the deciduous arboreal zone. H. verbana has been recorded from Switzerland and Italy to Turkey and Uzbekistan, which largely corresponds to the Mediterranean and sub-boreal steppe zone. H. orientalis is associated with mountainous areas in the sub-boreal eremial zone and occurs in Transcaucasian countries, Iran and Central Asia. H. troctina has been found in north-western Africa and Spain in the Mediterranean zone. 5. Based on the data gathered, and considering real and potential threats, global IUCN category Near Threatened is proposed for H. medicinalis, H. verbana, and H. orientalis, while H. troctina can only be assigned to category Data Deficient. Copyright © 2010 John Wiley & Sons, Ltd.
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Diverse molecular data demonstrate that commercially available medicinal leeches are not Hirudo medicinalis.
Proceedings of the Royal Society B: Biological Sciences, 2007Co-Authors: Mark E. Siddall, Peter Trontelj, Serge Utevsky, Mary Nkamany, Kenneth S. MacdonaldAbstract:The European medicinal leech is one of vanishingly few animal species with direct application in modern medicine. In addition to the therapeutic potential held by many protease inhibitors purified from leech saliva, and notwithstanding the historical association with quackery, Hirudo medicinalis has been approved by the United States Food and Drug Administration as a prescription medical device. Accurate annotation of bioactive compounds relies on precise species determination. Interpretations of developmental and neurophysiological characteristics also presuppose uniformity within a model species used in laboratory settings. Here, we show, with mitochondrial sequences and nuclear microsatellites, that there are at least three species of European medicinal leech, and that leeches marketed as H. medicinalis are actually Hirudo verbana. Beyond the obvious need for reconsideration of decades of biomedical research on this widely used model organism, these findings impact regulatory statutes and raise concerns for the conservation status of European medicinal leeches.
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a new species of the medicinal leech oligochaeta hirudinida Hirudo from transcaucasia and an identification key for the genus Hirudo
Parasitology Research, 2005Co-Authors: Serge Utevsky, Peter TronteljAbstract:A recent molecular phylogenetic study has suggested that the genus Hirudo contains a neglected species previously known as the orientalis coloration type of the medicinal leech Hirudo medicinalis. In this paper, the new species is formally described as Hirudo orientalis sp. n. It can most readily be identified by the grass green coloration of the dorsum, segmentally arranged pairs of black quadrangular or rounded dots on its paramarginal dorsal stripes and similarly arranged, but less regular light-colored markings on the predominantly black venter. It has medium-sized epididymes and an evenly coiled vagina. H. orientalis is known from Transcaucasia, Iran, and Uzbekistan. It is widely used in medicine as the “medicinal leech.” Very little is known about its exact distribution, specific habitat, and conservation status. The paper contains an identification key to all species of the genus Hirudo.
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celebrity with a neglected taxonomy molecular systematics of the medicinal leech genus Hirudo
Molecular Phylogenetics and Evolution, 2005Co-Authors: Peter Trontelj, Serge UtevskyAbstract:The medicinal leech is the most famous representative of the Hirudinea. It is one of few invertebrates widely used in medicine and as a scientiWc model object. It has recently been given considerable conservation eVort. Despite all attention there is confusion regarding the taxonomic status of diVerent morphological forms, with many diVerent species described in the past, but only two generally accepted at present. The results of the phylogenetic analysis of a nuclear (ITS2 + 5.8S rRNA) and two mitochondrial gene sequences (12S rRNA, COI) suggest that the genus Hirudo is monophyletic. It consists, apart form the type Hirudo medicinalis and the East Asian Hirudo nipponia, of three other, neglected species. All of them have already been described either as species or morphological variety, and can readily be identiWed by their coloration pattern. The type species is in weakly supported sister relation with Hirudo sp. n. (described as variety orientalis) from Transcaucasia and Iran. Sister to them stands Hirudo verbana from southeastern Europe and Turkey, which is nowadays predominantly bred in leech farms and used as ‘medicinal leech.’ The North African Hirudo troctina is the sister taxon to this group of Western Eurasian species, whereas the basal split is between H. nipponia and the Western Palaearctic clade.
Ekaterina Grafskaia - One of the best experts on this subject based on the ideXlab platform.
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draft genome sequences of Hirudo medicinalis and salivary transcriptome of three closely related medicinal leeches
BMC Genomics, 2020Co-Authors: Vladislav V. Babenko, Valentin A. Manuvera, Oleg V Podgorny, Artem S Kasianov, Alexander I Manolov, Ekaterina GrafskaiaAbstract:BackgroundSalivary cell secretion (SCS) plays a critical role in blood feeding by medicinal leeches, making them of use for certain medical purposes even today.ResultsWe annotated the Hirudo medici ...
William B Kristan - One of the best experts on this subject based on the ideXlab platform.
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Species-specific behavioral patterns correlate with differences in synaptic connections between homologous mechanosensory neurons
Journal of Comparative Physiology A, 2010Co-Authors: Michael J. Baltzley, Quentin Gaudry, William B KristanAbstract:We characterized the behavioral responses of two leech species, Hirudo verbana and Erpobdella obscura , to mechanical skin stimulation and examined the interactions between the pressure mechanosensory neurons (P cells) that innervate the skin. To quantify behavioral responses, we stimulated both intact leeches and isolated body wall preparations from the two species. In response to mechanical stimulation, Hirudo showed local bending behavior, in which the body wall shortened only on the side of the stimulation. Erpobdella , in contrast, contracted both sides of the body in response to touch. To investigate the neuronal basis for this behavioral difference, we studied the interactions between P cells. Each midbody ganglion has four P cells; each cell innervates a different quadrant of the body wall. Consistent with local bending, activating any one P cell in Hirudo elicited polysynaptic inhibitory potentials in the other P cells. In contrast, the P cells in Erpobdella had excitatory polysynaptic connections, consistent with the segment-wide contraction observed in this species. In addition, activating individual P cells caused asymmetrical body wall contractions in Hirudo and symmetrical body wall contractions in Erpobdella . These results suggest that the different behavioral responses in Erpobdella and Hirudo are partly mediated by interactions among mechanosensory cells.
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Species-specific behavioral patterns correlate with differences in synaptic connections between homologous mechanosensory neurons
Journal of Comparative Physiology A, 2010Co-Authors: Michael J. Baltzley, Quentin Gaudry, William B KristanAbstract:We characterized the behavioral responses of two leech species, Hirudo verbana and Erpobdella obscura , to mechanical skin stimulation and examined the interactions between the pressure mechanosensory neurons (P cells) that innervate the skin. To quantify behavioral responses, we stimulated both intact leeches and isolated body wall preparations from the two species. In response to mechanical stimulation, Hirudo showed local bending behavior, in which the body wall shortened only on the side of the stimulation. Erpobdella , in contrast, contracted both sides of the body in response to touch. To investigate the neuronal basis for this behavioral difference, we studied the interactions between P cells. Each midbody ganglion has four P cells; each cell innervates a different quadrant of the body wall. Consistent with local bending, activating any one P cell in Hirudo elicited polysynaptic inhibitory potentials in the other P cells. In contrast, the P cells in Erpobdella had excitatory polysynaptic connections, consistent with the segment-wide contraction observed in this species. In addition, activating individual P cells caused asymmetrical body wall contractions in Hirudo and symmetrical body wall contractions in Erpobdella . These results suggest that the different behavioral responses in Erpobdella and Hirudo are partly mediated by interactions among mechanosensory cells.
Michael J. Baltzley - One of the best experts on this subject based on the ideXlab platform.
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Differing synaptic strengths between homologous mechanosensory neurons
Invertebrate Neuroscience, 2014Co-Authors: Kaitlin R. Gibbons, Michael J. BaltzleyAbstract:Leeches have four mechanosensory pressure neurons (P cells) in each midbody ganglion. Within a ganglion, P cells show complex electrical and chemical connections that vary between species. In Hirudo verbana , stimulating one P cell causes a weak depolarization followed by a strong hyperpolarization in the other P cells; however, stimulating a P cell in Erpobdella obscura produces strong depolarizations in the other P cells. In this study, we examined interactions between P cells in the American medicinal leech Macrobdella decora . Not only is Macrobdella more closely related to Hirudo than to Erpobdella , but Hirudo and Macrobdella also have very similar behavioral responses to mechanical stimulation. Despite the phylogenetic relationship and behavioral similarities between the two species, we found that intracellular stimulation of one P cell in Macrobdella causes a depolarization in the other P cells, rather than the hyperpolarization seen in Hirudo . Experiments performed in a high Mg^2+, 0 Ca^2+ saline solution and a high Mg^2+, high Ca^2+ saline solution suggest that the P cells in Macrobdella have a monosynaptic excitatory connection, a polysynaptic inhibitory connection, and a weak electrical coupling, similar to the connections between P cells in Hirudo . The difference in net response of P cells between these two species seems to be based on differences in the strengths of the chemical connections. These results demonstrate that even when behavioral patterns are conserved in closely related species, the underlying neural circuitry is not necessarily tightly constrained.
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Species-specific behavioral patterns correlate with differences in synaptic connections between homologous mechanosensory neurons
Journal of Comparative Physiology A, 2010Co-Authors: Michael J. Baltzley, Quentin Gaudry, William B KristanAbstract:We characterized the behavioral responses of two leech species, Hirudo verbana and Erpobdella obscura , to mechanical skin stimulation and examined the interactions between the pressure mechanosensory neurons (P cells) that innervate the skin. To quantify behavioral responses, we stimulated both intact leeches and isolated body wall preparations from the two species. In response to mechanical stimulation, Hirudo showed local bending behavior, in which the body wall shortened only on the side of the stimulation. Erpobdella , in contrast, contracted both sides of the body in response to touch. To investigate the neuronal basis for this behavioral difference, we studied the interactions between P cells. Each midbody ganglion has four P cells; each cell innervates a different quadrant of the body wall. Consistent with local bending, activating any one P cell in Hirudo elicited polysynaptic inhibitory potentials in the other P cells. In contrast, the P cells in Erpobdella had excitatory polysynaptic connections, consistent with the segment-wide contraction observed in this species. In addition, activating individual P cells caused asymmetrical body wall contractions in Hirudo and symmetrical body wall contractions in Erpobdella . These results suggest that the different behavioral responses in Erpobdella and Hirudo are partly mediated by interactions among mechanosensory cells.
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Species-specific behavioral patterns correlate with differences in synaptic connections between homologous mechanosensory neurons
Journal of Comparative Physiology A, 2010Co-Authors: Michael J. Baltzley, Quentin Gaudry, William B KristanAbstract:We characterized the behavioral responses of two leech species, Hirudo verbana and Erpobdella obscura , to mechanical skin stimulation and examined the interactions between the pressure mechanosensory neurons (P cells) that innervate the skin. To quantify behavioral responses, we stimulated both intact leeches and isolated body wall preparations from the two species. In response to mechanical stimulation, Hirudo showed local bending behavior, in which the body wall shortened only on the side of the stimulation. Erpobdella , in contrast, contracted both sides of the body in response to touch. To investigate the neuronal basis for this behavioral difference, we studied the interactions between P cells. Each midbody ganglion has four P cells; each cell innervates a different quadrant of the body wall. Consistent with local bending, activating any one P cell in Hirudo elicited polysynaptic inhibitory potentials in the other P cells. In contrast, the P cells in Erpobdella had excitatory polysynaptic connections, consistent with the segment-wide contraction observed in this species. In addition, activating individual P cells caused asymmetrical body wall contractions in Hirudo and symmetrical body wall contractions in Erpobdella . These results suggest that the different behavioral responses in Erpobdella and Hirudo are partly mediated by interactions among mechanosensory cells.
