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1.
Oral Dis ; 24(1-2): 202-206, 2018 Mar.
Article En | MEDLINE | ID: mdl-29480601

OBJECTIVE: Bone marrow cell extract (BMCE) was previously reported to restore salivary gland hypofunction caused by irradiation injury. Proteins were shown to be the main active factors in BMCE. However, BMCE therapy requires multiple injections and protein denaturation is a concern during BMCE storage. This study aimed to preserve, by lyophilization (freeze-drying), the bioactive factors in BMCE. METHODS: We developed a method to freeze-dry BMCE and then to analyze its ingredients and functions in vivo. Freeze-dried (FD) BMCE, freshly prepared BMCE (positive control), or saline (vehicle control) was injected into the tail vein of mice that had received irradiation to damage their salivary glands. RESULTS: Results demonstrated that the presence of angiogenesis-related factors and cytokines in FD-BMCE remained comparable to those found in fresh BMCE. Both fresh and FD-BMCE restored comparably saliva secretion, increased cell proliferation, upregulated regenerative/repair genes, protected salivary acinar cells, parasympathetic nerves, and blood vessels from irradiation-damaged salivary glands. CONCLUSION: Lyophilization of BMCE maintained its bioactivity and therapeutic effect on irradiation-injured salivary glands. The advantages of freeze-drying BMCE are its storage and transport at ambient temperature.


Bone Marrow Cells , Cell Extracts/pharmacology , Radiation Injuries, Experimental/drug therapy , Salivary Glands/physiology , Salivation/drug effects , Acinar Cells/physiology , Angiogenesis Inducing Agents/analysis , Animals , Cell Extracts/chemistry , Cell Proliferation/drug effects , Cytokines/analysis , Female , Freeze Drying , Mice , Neovascularization, Physiologic/drug effects , Salivary Glands/cytology
2.
J Parasitol ; 104(2): 157-167, 2018 04.
Article En | MEDLINE | ID: mdl-29182486

Two new species of Staphylocystoides are described from masked shrews Sorex cinereus. Staphylocystoides oligospinosus n. sp. was collected from the vicinity of Missoula, Montana, United States, and Staphylocystoides parasphenomorphus n. sp. was collected from the vicinity of Whitehorse, Yukon Territory, Canada. Morphological differentiation from known species is provided. Both species are morphologically closest to Staphylocystoides sphenomorphus and to each other. Among other characters, S. oligospinosus n. sp. can be easily differentiated from all known species of the genus by unique cirrus armature, which consists of a short zone of small spines at the base of the cirrus, a few large sparsely distributed spines of varying size in the middle part of the cirrus, and hair-like microtriches densely covering the apical portion of the cirrus. Staphylocystoides parasphenomorphus n. sp. differs from S. oligospinosus n. sp. in a number of characters, most distinctly in cirrus armature, and from another morphologically similar species, S. sphenomorphus, in the number of proglottids, strobila size, number and size of rostellar hooks, and relative length of cirrus sac. Comparison of partial sequences of nuclear large ribosomal RNA subunit gene (1,310 base pairs [bp]) and mitochondrial NAD(P)H dehydrogenase subunit 1 gene (710 bp) strongly supports the status of the described forms as new species. This increases the number of Staphylocystoides species known in North America to 9 (5 parasitizing S. cinereus) and the total number of species in the genus to 12. Staphylocystoides parasphenomorphus n. sp. is the first named Staphylocystoides record in Canada.


Cestoda/classification , Cestode Infections/veterinary , Shrews/parasitology , Animals , Cestoda/genetics , Cestoda/ultrastructure , Cestode Infections/parasitology , DNA, Helminth/chemistry , DNA, Helminth/isolation & purification , Intestine, Small/parasitology , Microscopy, Electron, Scanning/veterinary , Montana , North America , Polymerase Chain Reaction/veterinary , Sequence Alignment/veterinary , Wetlands , Yukon Territory
3.
J Helminthol ; 91(4): 479-490, 2017 Jul.
Article En | MEDLINE | ID: mdl-27460259

We examined the associations between intestinal helminth infracommunity structure and infection parameters and the age, size, and year and region of collection of 130 female lesser scaup (Aythya affinis) during their 2014-2015 spring migrations through the upper Midwest, USA. We identified a total of 647,174 individual helminths from 40 taxa, including 20 trematodes, 14 cestodes, 4 nematodes and 2 acanthocephalans parasitizing lesser scaup within the study area. Lesser scaup were each infected with 2-23 helminth taxa. One digenean, Plenosoma minimum, is reported for the first time in lesser scaup and in the Midwest. Mean trematode abundance and total helminth abundance was significantly less in 2015 than 2014, and we suspect that colder weather late in 2015 impacted the intermediate host fauna and caused the observed differences. Brillouin's species diversity of helminths was greatest in the northernmost region of the study area, which coincides with the range of a non-indigenous snail that indirectly causes annual mortality events of lesser scaup. While host age and size were not determined to be influential factors of helminth infracommunity structure, non-parametric ordination and permutational analysis of co-variance revealed that year and region of collection explained differences in helminth infracommunities. Our results suggest that spatiotemporal variations play an important role in the structure of intestinal helminth infracommunities found in migrating lesser scaup hosts, and may therefore impact host ability to build endogenous reserves at certain stopover locations in the Midwest.


Anseriformes/parasitology , Bird Diseases/epidemiology , Bird Diseases/parasitology , Helminths/classification , Helminths/isolation & purification , Intestinal Diseases, Parasitic/veterinary , Animals , Biodiversity , Female , Helminthiasis/epidemiology , Helminthiasis/parasitology , Intestinal Diseases, Parasitic/epidemiology , Intestinal Diseases, Parasitic/parasitology , Midwestern United States/epidemiology , Parasite Load , Spatio-Temporal Analysis
4.
J Helminthol ; 90(3): 294-7, 2016 May.
Article En | MEDLINE | ID: mdl-25772632

The air sacs of free-ranging birds of prey (n= 652) from southern Italy, including 11 species of Accipitriformes and six of Falconiforms, were examined for infections with Serratospiculum tendo (Nematoda: Diplotriaenoidea). Of the 17 species of birds examined, 25 of 31 (80.6%) peregrine falcons (Falco peregrinus) from Calabria Region and a single northern goshawk (Accipiter gentilis) from Campania Region were infected with S. tendo, suggesting a strong host specificity for the peregrine falcon. The northern goshawk and 18 of 25 infected peregrine falcons showed cachexia and all infected birds had bone fractures. At gross examination, air sacculitis and pneumonia were the most common lesions in infected birds. Microscopically, the air-sac walls showed thickening of the smooth muscle cells, resulting in a papillary appearance, along with hyperplasia of the mesothelium and epithelium, and foci of plasma cell infiltration and macrophages associated with several embryonated eggs and adult parasites. Extensive areas of inflammation were found in the lungs, characterized by lymphocytes, macrophages and fibroblasts surrounding embryonated eggs. The northern goshawk also had detachment of the dextral lung with several necrotic foci. In this case, the death of the bird was directly attributed to S. tendo infection. Lesions and pathological changes observed here suggest that S. tendo can cause disease.


Bird Diseases/epidemiology , Bird Diseases/parasitology , Raptors , Spirurida Infections/veterinary , Spirurida/isolation & purification , Air Sacs/parasitology , Animals , Bird Diseases/pathology , Female , Histocytochemistry , Italy , Lung/pathology , Male , Prevalence , Spirurida Infections/epidemiology , Spirurida Infections/parasitology , Spirurida Infections/pathology
5.
J Parasitol ; 101(3): 382-5, 2015 Jun.
Article En | MEDLINE | ID: mdl-25574753

Heligmosomoides americanus is shown by molecular phylogenetic analysis of 3 nuclear (28S, ITS1, and ITS2) and 2 mitochondrial (cytochrome oxidase 1 and cytochrome b) loci to be a distinct species of heligmosomid nematode with a long-independent evolutionary history, and not a subspecies of Heligmosomoides polygyrus . Rather than being a recent arrival in North America, the species probably originated as a Beringian immigrant with the host vole Phenacomys, approximately 2 million years ago (MYA).


Arvicolinae/parasitology , Rodent Diseases/parasitology , Trichostrongyloidea/classification , Trichostrongyloidiasis/veterinary , Animals , British Columbia , Cytochromes b/genetics , DNA, Ribosomal Spacer/genetics , Electron Transport Complex IV/genetics , Genetic Markers , Molecular Sequence Data , Montana , Phylogeny , RNA, Ribosomal, 28S/genetics , Sequence Alignment/veterinary , Trichostrongyloidea/anatomy & histology , Trichostrongyloidea/genetics , Trichostrongyloidiasis/parasitology
6.
J Helminthol ; 87(3): 277-85, 2013 Sep.
Article En | MEDLINE | ID: mdl-22691545

Parasite assemblages of the Western whip snake Hierophis viridiflavus carbonarius were investigated from the Calabria region in southern Italy. A total of 14 parasite taxa including 6 nematodes, 3 acanthocephalans, 2 cestodes, 2 digeneans and a single pentastomid was identified. Within the study area, H. v. carbonarius serves as the final host for seven species of helminths, of which only four (Hexametra quadricornis, Kalicephalus viperae, Paracapillaria sonsinoi and Renifer aniarum) can be considered as snake specialists, while one (Oswaldocruzia filiformis) is shared with other reptiles and amphibians, and two (Paradistomum mutabile and Rhabdias fuscovenosa) with lizards. A large proportion of larval forms of six helminth taxa (about 95% of all helminths collected) was found, for which H. v. carbonarius serves as an intermediate and/or paratenic host; however, adult stages of helminths were prevalent in snakes with snout-to-vent length greater than 70 cm. Our results suggest that ontogenetic and ecological factors should exert a strong influence upon the helminth assemblage of Western whip snakes. We concluded that H. v. carbonarius plays an important role in southern Italy as an intermediate/paratenic host for species of helminths infecting vertebrate groups which may include this snake species within their feeding chain. Eleven taxa, including three potential agents of zoonosis, were added to the poorly known parasite fauna of this host.


Biodiversity , Colubridae/parasitology , Parasites/classification , Parasites/isolation & purification , Parasitic Diseases, Animal/parasitology , Animals , Italy/epidemiology , Parasitic Diseases, Animal/epidemiology
7.
J Wildl Dis ; 48(3): 707-16, 2012 Jul.
Article En | MEDLINE | ID: mdl-22740536

African savannah elephants (Loxodonta africana) are an ecologically and economically important species in many African habitats. However, despite the importance of elephants, research on their parasites is limited, especially in wild populations. Currently, we lack genetic tools to identify elephant parasites. We present genetic markers from ribosomal DNA (rDNA) and mitochondrial DNA (mtDNA) to identify five elephant-specific nematode parasites in the family Strongylidae: Murshidia linstowi, Murshidia longicaudata, Murshidia africana, Quilonia africana, and Khalilia sameera. We collected adult nematodes from feces deposited by wild elephants living in Amboseli National Park, Kenya. Using both morphologic and genetic techniques, we found that the internal transcribed spacer (ITS) region in rDNA provides a reliable marker to distinguish these species of strongyles. We found no evidence for cryptic genetic species within these morphologic species according to the cox-1 region of mtDNA. Levels of genetic diversity in strongyles from elephants were consistent with the genetic diversity seen within other strongyle species. We anticipate that these results will be a useful tool for identifying gastrointestinal nematode parasites in elephants.


Elephants/parasitology , Genetic Variation , Strongylida Infections/veterinary , Strongylus/genetics , Animals , Animals, Wild/parasitology , DNA, Mitochondrial/analysis , Feces/parasitology , Genetic Markers , Kenya , Strongylida Infections/parasitology , Strongylus/classification
8.
J Helminthol ; 86(1): 38-40, 2012 Mar.
Article En | MEDLINE | ID: mdl-21294936

Very little is known about parasitic diseases of eastern box turtles (Terrapene carolina carolina). The objective of this study was to examine the parasitic fauna of eastern box turtles collected from southern Indiana, USA. Turtles (n = 40) were salvaged mostly as road kills from southern Indiana between May and October 2009. Seven species of helminths in total were found parasitizing the gastrointestinal tract, including two digenean trematodes (Brachycoelium salamandrae and Telorchis robustus) and five nematodes (Oswaldocruzia pipiens, Cosmocercoides dukae, Falcaustra affinis, F. chelydrae and Serpinema trispinosus). We report prevalence, abundance and mean intensity of infection for all helminths. Helminths were not found in any other organs examined (heart, gonads, liver, heart, kidney and urinary bladder) and no ectoparasites were found. Overall, mean intensity of infections was low (1-14 parasites/host), suggesting that these parasites are unlikely to be associated with negative health impacts. This constitutes the first study of this kind for Indiana.


Helminthiasis, Animal/parasitology , Helminths/isolation & purification , Turtles/parasitology , Animals , Helminths/classification , Indiana
9.
J Parasitol ; 97(2): 364-6, 2011 Apr.
Article En | MEDLINE | ID: mdl-21506790

The helminth community of the Mediterranean gull (Ichthyaetus melanocephalus) from the Calabria region in southern Italy was examined. Ten species of helminths, including 2 cestodes (Alcataenia larina and Tetrabothrius cylindraceus), 4 digeneans ( Aporchis massiliensis , Brachylaima fuscatum, Cardiocephaloides longicollis, and Ornithobilharzia canaliculata), and 4 nematodes (Eucoleus contortus, Capillaria sp., Cosmocephalus obvelatus, and Paracuaria adunca), were found. The Mediterranean gull represents new host records for A. larina, A. massiliensis, B. fuscatum, and E. contortus; all species, except C. longicollis and O. canaliculata, constitute new locality records. The gastrointestinal helminth community of I. melanocephalus consisted of 9 species but, at the infracommunity level, species richness, diversity, and total helminth abundance are among the lowest reported from any gull species. Two cestode species accounted for 81% of all helminth specimens found.


Bird Diseases/parasitology , Charadriiformes/parasitology , Helminthiasis, Animal/parasitology , Helminths/classification , Intestinal Diseases, Parasitic/veterinary , Animal Migration , Animals , Bird Diseases/epidemiology , Female , Gastrointestinal Tract/parasitology , Helminthiasis, Animal/epidemiology , Helminths/isolation & purification , Intestinal Diseases, Parasitic/epidemiology , Intestinal Diseases, Parasitic/parasitology , Italy/epidemiology , Male , Prevalence
10.
Adv Parasitol ; 57: 191-253, 2004.
Article En | MEDLINE | ID: mdl-15504539

Trematodes in the genus Ribeiroia have an indirect life cycle involving planorbid snails as first intermediate hosts, fishes or amphibians as second intermediate hosts and birds or mammals as definitive hosts. Although rarely pathogenic in definitive hosts, Ribeiroia infection can cause severe pathology and mortality in snails and amphibians. This group of parasites has gained notoriety for its prominent rol in the recent rash of amphibian deformities in North America. Under some circumstances, these malformations may enhance parasite transmission by rendering infected amphibian hosts more susceptible to definitive host predators. However, increasing reports of malformations in North American amphibian populations emphasize the importance of understanding infection patterns. Here we review important aspects of the biology, ecology, life cycle and pathogenesis of parasites in the genus Ribeiroia and identify priorities for future research. Based on available morphological descriptions and preliminary molecular data, three species of Ribeiroia are recognized: R. ondatrae in the Americas, R. marini in the Caribbean and R. congolensis/C. lileta in Africa. We further evaluate the influence of abiotic and biotic factors in determining the intensity and prevalence of Ribeiroia infection and malformations in amphibians, highlighting the importance of habitat alteration and secondary factors (e.g. aquatic eutrophication, contaminants) in promoting infection. Although not a "new" parasite, Ribeiroia may have increased in range, prevalence, or intensity in recent years, particularly within amphibian hosts. Nevertheless, while much is known about this intriguing group of parasites, there remains much that we do not know. Particular importance for future research is placed on the following areas: evaluating the phylogenetic position of the genus, establishing the molecular mechanism of parasite-induced malformations in amphibians, isolating the drivers of parasite transmission under field conditions and studying the consequences of malformations for parasite and host populations. Investigation of these questions will benefit enormously from a multidisciplinary approach that effectively integrates parasitology, developmental biology, immunology, herpetology and aquatic ecology.


Amphibians/parasitology , Ecosystem , Trematoda/physiology , Trematoda/pathogenicity , Animals , Bird Diseases/parasitology , Bird Diseases/pathology , Fish Diseases/parasitology , Fish Diseases/pathology , Host-Parasite Interactions , Life Cycle Stages , Snails/parasitology , Trematode Infections/parasitology , Trematode Infections/pathology , Trematode Infections/veterinary
11.
Vet Rec ; 154(1): 17-20, 2004 Jan 03.
Article En | MEDLINE | ID: mdl-14725424

The prevalence of parasitic helminths in the digestive tract of 119 diurnal raptors (Falconiformes), which had died in a wildlife rehabilitation centre in Catalonia, was studied. The birds belonged to 13 species, with 100 of them (84 per cent) being kestrels (Falco tinnunculus), buzzards (Buteo buteo), sparrowhawks (Accipiter nisus) and goshawks (Accipiter gentilis). Ninety-five of the birds (79.8 per cent) were infected with helminths. Nematodes were the most frequently found helminth (75.6 per cent), followed by trematodes, cestodes and ancanthocephalans. All the buzzards and sparrowhawks and 92 per cent of the goshawks were infected, but only 59 per cent of the kestrels were infected.


Bird Diseases/epidemiology , Bird Diseases/parasitology , Helminths/isolation & purification , Intestinal Diseases, Parasitic/veterinary , Raptors , Animals , Helminthiasis, Animal/epidemiology , Helminthiasis, Animal/parasitology , Helminths/classification , Intestinal Diseases, Parasitic/epidemiology , Intestinal Diseases, Parasitic/parasitology , Prevalence , Spain/epidemiology
12.
Mem Inst Oswaldo Cruz ; 97(4): 597-8, 2002 Jun.
Article En | MEDLINE | ID: mdl-12118298

We report Pelecitus helicinus Railliet & Henry, 1910 from 13 species of birds of 2 orders and 7 families, collected from the states of São Paulo and Mato Grosso, Brazil. All 13 constitute new host records for this nematode. In addition, we report the first record of Aprocta golvani Diaz-Ungria, 1963 from Brazil and Monasa nigrifrons (Bucconidae), as well as a number of other nematode records from Neotropical birds.


Birds/parasitology , Nematoda/isolation & purification , Animals , Brazil , Female , Filarioidea/isolation & purification , Male
13.
Mem. Inst. Oswaldo Cruz ; 97(4): 597-598, June 2002. tab
Article En | LILACS | ID: lil-314528

We report Pelecitus helicinus Railliet & Henry, 1910 from 13 species of birds of 2 orders and 7 families, collected from the states of Säo Paulo and Mato Grosso, Brazil. All 13 constitute new host records for this nematode. In addition, we report the first record of Aprocta golvani Diaz-Ungria, 1963 from Brazil and Monasa nigrifrons (Bucconidae), as well as a number of other nematode records from Neotropical birds


Animals , Male , Female , Birds , Nematoda , Brazil , Filarioidea
14.
Contemp Top Lab Anim Sci ; 40(6): 22-4, 2001 Nov.
Article En | MEDLINE | ID: mdl-11703052

The identification of a tapeworm (Rodentolepis nana, formerly named Hymenolepis nana) infection in a research breeding colony of sand rats (Psammomys obesus obesus) was complicated because of the unexpected long length (< 150 mm) of the worms. Other morphologic features that were consistent with this identification included the number (24), size (16 mm), and shape of the hooks on the rostellum. No evidence of intermediate hosts was found in the colony. Previous surveys of natural populations of sand rats had not identified this tapeworm. However, a detailed search of the literature revealed that variation in the size of R. nana had been reported, thus supporting the final identification of the tapeworm. R. nana is important and interesting because of its zoonotic potential and because it is the only tapeworm that is able to infect its definitive host without use of an intermediate host. This report is presented to help clarify the ambiguity found in the laboratory animal literature about the differences in the size of R. nana among rodent species used in research.


Gerbillinae/parasitology , Hymenolepiasis/veterinary , Hymenolepis/anatomy & histology , Hymenolepis/isolation & purification , Animals , Animals, Laboratory , Female , Hymenolepiasis/pathology , Hymenolepis/pathogenicity , Male
15.
J Parasitol ; 87(5): 1199-202, 2001 Oct.
Article En | MEDLINE | ID: mdl-11695400

Taxonomic characters for identification of Turgida turgida Rudolphi, 1819, a parasitic nematode of the Virginia opossum Didelphis virginiana, were studied by scanning electron microscopy. The distinguishing feature of the cephalic end is the presence of numerous denticles, structures associated with the internal tooth, and 2 spongelike areas on the inner side of each pseudolabia. The posterior end of male T. turgida differs from that in other species of Physalopteridae by the number of caudal papillae (22), truncated postcloacal papilla, and patterns of ventrocaudal ornamentation.


Nematoda/anatomy & histology , Opossums/parasitology , Animals , California , Female , Male , Microscopy, Electron, Scanning , Nematoda/ultrastructure , Nematode Infections/parasitology , Nematode Infections/veterinary
16.
Mem Inst Oswaldo Cruz ; 96(6): 827-30, 2001 Aug.
Article En | MEDLINE | ID: mdl-11562710

Thirteen species of helminth parasites were recovered from six species of charadriid shorebirds (Aves: Charadriiformes) from Belize: the ruddy turnstone, Arenaria interpres, the snowy plover, Charadrius alexandrinus, the semipalmated plover, C. semipalmatus, the killdeer, C. vociferus, the white-rumped sandpiper, Calidris fuscicollis, and the black-bellied plover, Pluvialis squatarola. Cestode species were predominant (N = 8), followed by trematode species (N = 3) and acanthocephala (N = 2). The trematode, Paramaritremopsis solielangi infected four of the six species of hosts. The cestodes, Nadejdolepis litoralis and N. paranitidulans infected three and two host species respectively. Helminth parasite species were contagious (clumped) and not evenly distributed among hosts. Twelve of the 13 species were generalists. The one specialist Microphallus kinsellae was recovered from one C. fuscicollis. Three of the four types of feeding guilds were present and in approximately the same number. All but M. kinsellae have been reported from other species of hosts, mostly from Eurasia and North America.


Birds/parasitology , Helminths/isolation & purification , Animals , Belize , Helminths/classification
17.
J Zoo Wildl Med ; 32(4): 523-5, 2001 Dec.
Article En | MEDLINE | ID: mdl-12785711

Numerous nematode cysts were observed throughout the mesentery and on the surface of gastrointestinal organs in a whooping crane (Grus americana) that was found dead in a central Florida marsh. Morphology of the excysted nematodes most closely resembled third-stage larvae in the order Spirurida but were not similar to any species previously reported in whooping cranes. Evidence presented suggests that the larvae may be Physocephalus sexalatus, a swine spirurid in the subfamily Ascaropsinae that is commonly found encapsulated in birds, amphibians, and reptiles. We suspect that the whooping crane may potentially serve as a transport host for this parasite.


Bird Diseases/parasitology , Nematoda/isolation & purification , Nematode Infections/veterinary , Animals , Animals, Wild/parasitology , Bird Diseases/pathology , Birds , Fatal Outcome , Florida , Host-Parasite Interactions , Intestine, Small/parasitology , Larva , Male , Mesentery/parasitology , Nematode Infections/parasitology , Nematode Infections/pathology
18.
Neurogastroenterol Motil ; 12(6): 509-16, 2000 Dec.
Article En | MEDLINE | ID: mdl-11123705

We investigated the effect of phencyclidine (PCP) on three native delayed rectifier K+ currents and three channels cloned from canine and human circular colonic myocytes using voltage-clamp techniques. Native delayed rectifier K+ current in canine circular colon is composed of at least three components: (i) a rapidly activating, 4-aminopyridine-sensitive component (termed IdK(f)); (ii) a slowly activating, tetraethylammonium (TEA)-sensitive component (IdK(s)); and (iii) a rapidly activating, TEA-sensitive component, which has a steady-state inactivation curve shifted towards more negative potentials (IdK(n)). PCP blocked all three components with EC50 values of 45, 27 and 59 micromol L-1, respectively. Blocking was neither use-dependent nor voltage-dependent. Delayed rectifier K+ channels cloned from canine (Kv1.2, Kv1.5) and from human (Kv2.2) colon were expressed in Xenopus oocytes. PCP blocked all three currents with similar potency. In contrast, PCP (up to 10-4 mol L-1) did not reduce the magnitude of Ca2+-dependent outward current of large conductance Ca2+-activated K+ channels (BK channels).


Colon/physiology , Excitatory Amino Acid Antagonists/pharmacology , Muscle, Smooth/physiology , Phencyclidine/pharmacology , Potassium Channels, Voltage-Gated , Potassium Channels/physiology , Animals , Calcium/metabolism , Cloning, Molecular , Colon/chemistry , Colon/cytology , Cyclic AMP/metabolism , Delayed Rectifier Potassium Channels , Dogs , Female , Gastrointestinal Motility/drug effects , Humans , Ion Channel Gating/drug effects , Ion Channel Gating/physiology , Male , Membrane Potentials/drug effects , Membrane Potentials/physiology , Muscle Fibers, Skeletal/cytology , Muscle Fibers, Skeletal/physiology , Muscle, Smooth/chemistry , Muscle, Smooth/cytology , Patch-Clamp Techniques , Potassium Channel Blockers , Shab Potassium Channels , Xenopus laevis
19.
Br J Pharmacol ; 130(4): 857-66, 2000 Jun.
Article En | MEDLINE | ID: mdl-10864893

Two electrode voltage clamp and single channel recordings were used to investigate the actions of various ATP-sensitive K(+) (K(ATP)) channel inhibitors on cloned K(ATP) channels, expressed in Xenopus oocytes and HEK 293 cells. Oocytes expressing Kir6.2 and SUR1 gave rise to inwardly rectifying K(+) currents following bath application of 3 mM sodium azide. Inside-out recordings from non-azide treated oocytes demonstrated the presence of K(ATP) channels which were activated by direct application of 3 mM azide and 0.1 mM Mg-ATP. Tolbutamide inhibited azide-induced macroscopic Kir6.2-SUR1 currents, recorded from Xenopus oocytes, with an IC(50) value similar to native K(ATP) channels. Ciclazindol and englitazone also inhibited these currents in a concentration-dependent manner, but with relative potencies substantially less than for native K(ATP) channels. Single channel currents recorded from inside-out patches excised from oocytes expressing Kir6.2-SUR1 currents were inhibited by tolbutamide, Mg-ATP, englitazone and ciclazindol, in the absence of azide, with potencies similar to native K(ATP) channels. In the presence of azide, Kir6.2-SUR1 currents were inhibited by englitazone and tolbutamide but not ciclazindol. Single channel currents derived from Kir6.2Delta26, expressed in HEK 293 cells, were inhibited by ciclazindol and englitazone irrespective of the absence or presence of SUR1. In conclusion, heterologously expressed Kir6.2 and SUR1 recapitulate the pharmacological profile of native pancreatic beta-cell K(ATP) channels. However, currents induced by azide exhibit a substantially reduced sensitivity to ciclazindol. It is likely that ciclazindol and englitazone inhibit K(ATP) currents by interaction with the Kir6.2 subunit.


ATP-Binding Cassette Transporters , Benzopyrans/pharmacology , Indoles/pharmacology , Membrane Potentials/drug effects , Potassium Channels, Inwardly Rectifying , Potassium Channels/drug effects , Receptors, Drug/drug effects , Sodium Azide/pharmacology , Thiazoles/pharmacology , Thiazolidinediones , Adenosine Triphosphate/pharmacology , Adenosine Triphosphate/physiology , Animals , Cell Line , Dose-Response Relationship, Drug , Female , Glyburide/pharmacology , Humans , Mice , Microinjections , Oocytes , Potassium Channels/genetics , Potassium Channels/physiology , RNA, Complementary/administration & dosage , Receptors, Drug/genetics , Receptors, Drug/physiology , Sulfonylurea Receptors , Tolbutamide/pharmacology , Xenopus laevis
20.
J Zoo Wildl Med ; 29(3): 331-7, 1998 Sep.
Article En | MEDLINE | ID: mdl-9809609

Necropsies performed between 1989 and 1995 on 15 African rope squirrels (Funisciurus substriatus) and 20 African ground squirrels (Xerus erythropus) from the Baltimore Zoo revealed 13 cases of gongylonemiasis. Nematodes were embedded in the epithelium of the esophagus, pharynx, buccal mucosa, and tongue, resulting in varying degrees of esophagitis, pharyngitis, stomatitis, and glossitis, respectively. Routine fecal examinations were negative, and the nematodes appeared to be unaffected by repeated treatments with ivermectin. Most of the affected animals had shown clinical signs of dyspnea and/or inanition and emaciation. Suppurative rhinitis was also a frequent finding at necropsy and was associated with the presence of the nematodes in eight animals. Dissection of whole nematodes from formalin-fixed specimens revealed morphologic features consistent with Gongylonema macrogubernaculum, a species previously only reported in nonhuman primates. The squirrels were housed in the same building with numerous primate species, and a review of pathology records revealed esophageal gongylonemiasis in three lion-tailed macaques (Macaca silenus), lingual gongylonemiasis in a spotnose monkey (Cercopithecus buettikoferi), and buccal gongylonemiasis in a brown-headed tamarin (Saguinus fuscicollis). Examination of whole nematodes dissected from one of the lion-tailed macaques also demonstrated the unique morphology of G. macrogubernaculum. Nematodes belonging to the species Gongylonema are acquired by ingestion of the intermediate host, the cockroach. This is the first report of G. macrogubernaculum in a nonprimate species and suggests that captive African squirrels can serve as reservoir hosts for this parasite in a zoo environment.


Macaca/parasitology , Monkey Diseases/pathology , Rodent Diseases/pathology , Sciuridae/parasitology , Spirurida Infections/veterinary , Spiruroidea/isolation & purification , Animals , Animals, Zoo/parasitology , Esophagus/parasitology , Esophagus/pathology , Female , Male , Microscopy, Phase-Contrast/veterinary , Monkey Diseases/parasitology , Mouth Mucosa/parasitology , Mouth Mucosa/pathology , Pharynx/parasitology , Pharynx/pathology , Rodent Diseases/parasitology , Spirurida Infections/parasitology , Spirurida Infections/pathology , Spiruroidea/anatomy & histology , Tongue/parasitology , Tongue/pathology
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