Publications

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the greening of polar bears in zoos. 1979109768
parasite-related lesions in a bearded seal, erignathus barbatus.a free-ranging adult male bearded seal (erignathus barbatus) killed by polar bears was salvaged and examined at necropsy. significant findings included diffuse intrahepatic bile duct fibrosis and chronic cholangitis; multiple nodules of chronic fibrosing pancreatitis; and gastric ulcers. trematode eggs (family campulidae) were found in the pancreatic nodules. these eggs and the trematodes that produced them probably caused the pancreatic and liver lesions. phocanema decipiens and contracaecum os ...1979113564
status of trichinosis in bears in the atlantic provinces of canada 1971--1976.during 1971 to 1976 inclusive, 73 black bears, ursus americanus and one polar bear, thalarctos maritimus, originating in the atlantic provinces of canada were examined for the presence of trichinosis. the polar bear was infected but all of the black bears were negative.1978667710
observations on a trichinella spiralis isolate from a polar bear. 1978739315
on the tryptic peptides from hemoglobin chains of six carnivores.the amino acid compositions of the tryptic peptides of the following carnivore hemoglobin chains have been determined: gray fox (urocyon cineroargenteus); raccoon (procyon lotor); polar bear (thalarctos maritimus); coati mundi (nasua nasua) beta chain; coati mundi (nasua narica) two beta chains; cat (felis catus) alpha chain; and lion (pantbera leo) beta chain. these provide a basis for future sequencing of these hemoglobins and construction of an evolutionary tree. the specific results are summ ...1977864727
chemotherapy of helminthiasis among wild mammals. ii. baylisascaris transfuga (rudolphi, 1819) sprent, 1968 infection of polar bear.effective chemotherapy by mebendazole of baylisascaris transfuga infection of five polar bears is reported and a control measure programme directed towards limiting the infection under the prevailing condition is discussed.19761015484
dermatophilosis in two polar bears.dermatophilosis was diagnosed in 2 of 13 captive polar bears (thalarctos maritimus), causing generalized dermatitis of 3 years' and 6 months' duration, respectively. progressive clinical signs included yellowing and darkening of the hair, pruritus, encrustation of skin, and reluctance to bathe. dramatic resolution of lesions occurred during 8 weeks of twice-weekly intramuscular treatment with long-acting penicillin.19751176347
suppression of guinea pig ileum induced contractility by plasma albumin of hibernators.previous studies suggest that hibernation may be regulated by internal opioids and that the putative "hibernation induction trigger" (hit) may itself be an opioid. this study examined the effect of plasma albumin (known to bind hit) on induced contractility of the guinea pig ileum muscle strip. morphine (400 nm) depressed contractility and 100 nm naloxone restored it. ten milligrams of lyophilized plasma albumin fractions from hibernating ground squirrels, woodchucks, black bears, and polar bear ...19921409805
the occurrence of rabies in the svalbard islands of norway.after the first recorded outbreak of rabies in the svalbard islands (norway) in 1980, brain tissue from 817 trapped arctic foxes (alopex lagopus) was tested for rabies by a direct fluorescent antibody test. during the same period (1980 to 1990), 29 arctic foxes, 23 polar bears (ursus maritimus), 19 reindeer (rangifer tarandus) and five ringed seals (phoca hispida) were also tested using the same technique. these animals had either been found dead, killed because of abnormal behavior or were appa ...19921548803
conservation of the sequence of the alzheimer's disease amyloid peptide in dog, polar bear and five other mammals by cross-species polymerase chain reaction analysis.neuritic plaque and cerebrovascular amyloid deposits have been detected in the aged monkey, dog, and polar bear and have rarely been found in aged rodents (biochem. biophy. res. commun., 12 (1984) 885-890; proc. natl. acad. sci. u.s.a., 82 (1985) 4245-4249). to determine if the primary structure of the 42-43 residue amyloid peptide is conserved in species that accumulate plaques, the region of the amyloid precursor protein (app) cdna that encodes the peptide region was amplified by the polymeras ...19911656157
energetic output of subadult polar bears (ursus maritimus): resting, disturbance and locomotion.1. indirect calorimetry was used to determine metabolic rates in subadult polar bears at rest after human-controlled disturbance and at four rates of locomotion. 2. disturbance factors that do not result in locomotion would only have a significant effect on energy expenditure if they occurred over an extended period of time. 3. human disturbance resulting in locomotion would have a relatively high energetic cost to individual animals. 4. polar bears may require a relatively high energetic output ...19911673885
present status of trichinellosis in japan.there have been three mass outbreaks of human trichinellosis in japan. the first was in 1974 in iwasaki, aomori prefecture, involving a group of hunters who ate raw meat of a black bear they had shot. of the 20 people who ate the bear meat raw, 15 showed clinical symptoms of trichinellosis. the second outbreak was experienced in sapporo, hokkaido, in 1980. the patients had eaten the raw meat of a brown bear served in a local restaurant. twelve people were diagnosed positive on the basis of clini ...19911822910
[experiences with ivermectin in exotic animals: scabies in camelids (camelus bactrianus, lama guanicoe, l. glama) and scabies and roundworms in bears (thalarctos maritimus and ursus arctos)].for the control of scabies in tylopodes (l. bactrianus, l. guanicoe, l. glama) and brown bears 0.2 mg/kg body weight (1 ml/50 kg body weight) of ivermectin subcutaneously injected proved to be remedy of choice. in kodiak-bears the oral application of ivomec-solution was effective against ascariasis, not, however, in polar bears. sufficient effect was reached only once, whereas equalan-paste proved to be highly effective. despite of strong hygienic measures continous follow-up treatment for the p ...19912025214
observation of a polar bear with rabies.on 1 november 1989 the first confirmed case of rabies in a polar bear (ursus maritimus) was encountered by inuit hunters in the vicinity of cape kendall, southampton island, northwest territories (canada). the adult male polar bear had posterior paralysis. rabies was detected by mouse inoculation and a positive immunoperoxidase reaction on spinal cord and gasserian ganglion from the bear. histologic lesions in the lumbar region of the spinal cord were consistent with the posterior paralysis. the ...19912067058
characterization of a trichinella isolate from polar bear.an isolate of trichinella of polar bear origin was studied by isoenzymatic typing. it was found referable to trichinella nativa. while the wistar rats proved nearly refractory to this isolate, the swiss albino mice were highly susceptible. ninety-one per cent of the cystic lesions in the diaphragm of the polar bear contained viable larvae after over 20 years of acquisition of the infection by the host which is a case of extreme adaptability of the parasite to its host. the anatomo-pathological a ...19902222005
is the polar bear (ursus maritimus) a hibernator? continued studies on opioids and hibernation.polar bear behavior and biochemistry suggest they may have the ability to hibernate year-round, even though this species is not considered to be a true hibernator. this observation, plus the discovery of a hibernation-induction trigger (hit) in the blood of black bears, prompted the examination of polar bear blood collected throughout the year for evidence of hit, and to determine if it displayed opioid activity, as black bear blood does. a bioassay was conducted by injecting summer 13-lined gro ...19902339159
conservation of diagnostic antigen epitopes among biologically diverse isolates of trichinella spiralis.crude and immunoaffinity-purified excretory-secretory antigens derived from a domestic pig isolate of trichinella spiralis were used in an enzyme-linked immunosorbent assay to test serum from mice infected with 25 different pig and wild animal isolates of t. spiralis sspp. all of the sera were found positive by elisa using either of the antigen preparations, indicating all isolates shared certain antigen epitopes. excretory-secretory antigens were prepared from 3 distinct isolates of t. spiralis ...19862434638
immobilization of polar bears (ursus maritimus) with telazol in the canadian arctic.in 1986, 213 polar bears (ursus maritimus) were immobilized with telazol on the sea ice of the eastern beaufort sea during april and may, and 106 along the western coast of hudson bay near churchill, manitoba (canada) in september. no animals died from handling. the efficacy of this drug at different seasons and the physiological responses of the immobilized bears were compared. a single injection of 8 to 9 mg of telazol per kg of body weight gave a rapid full immobilization with satisfactory an ...19892716095
subclinical lumbar polyradiculopathy in aged domestic, laboratory, and exotic mammalian species--a light and selected electron microscopic study.lumbar polyradiculopathy, characterized by ballooning myelin sheaths and axonal distortion, was documented in multiple, aged, domestic, laboratory, and exotic mammalian species. animals studied that exhibited this nerve rootlet change included the goat, sheep, pig, white-tailed deer, gerbil, vole, ferret, beaver, hedgehog, chinchilla, north chinese leopard, lion, cheetah, mountain lion, llama, east african eland, uganda giraffe, polar bear, and drill. ultrastructurally, lumbar nerve rootlets fro ...19892766747
acute gastric dilatation and volvulus in a free-living polar bear.a large, adult male polar bear (ursus maritimus) was found dead on a barrier island north of prudhoe bay, alaska (usa), in june 1987. there were no external signs of trauma. a twisted distended stomach, distinctive parenchymal and fascial congestion, and significant difficulty in repositioning the anterior abdominal organs, indicated that gastric dilatation-volvulus (gdv) was the proximate cause of death. polar bears frequently consume large quantities of food at one time and have large stomachs ...19892810562
the fatty acid composition of northern-canadian marine and terrestrial mammals.the low mortality from cardiovascular disease in greenland eskimos has been attributed to their consumption of diets rich in omega-3 fatty acids. these fatty acids are found in fish and marine mammal lipids. whereas the fatty acid composition of several fish species has been documented, information is more limited on the mammals which feature significantly in the diets of many arctic populations. this study investigated the fatty acid composition of commonly eaten marine mammals, as well as the ...19872890267
the molecular phylogenic tree of the genus trichinella constructed from isozyme patterns.six zymograms were compared for extracts of muscle-stage larvae of the seven trichinella isolates, using isoelectric focusing in polyacrylamide gels. the isozyme patterns of acid phosphatase among them fell into four types. t. pseudospiralis from a raccoon and the polar strain from a polar bear formed type 1 and type 2, respectively. the iwasaki strain from a japanese black bear and the yamagata strain from a raccoon dog, both from japan, were type 3. type 4 consisted of three remaining strains, ...19883057491
neurofibrillary tangles and senile plaques in aged bears.in aged human beings and in individuals with age-associated degenerative disorders, particularly alzheimer's disease (ad), neurons develop cytoskeletal abnormalities, including neurofibrillary tangles (nft) and senile plaques (sp). senile plaques occur in several nonhuman species; however, nft, with ultrastructural or immunocytochemical similarities to those occurring in humans, have not been identified in other mammals. in this study of five aged bears (ursus, 20-30 years of age), we identified ...19883171607
conservation of brain amyloid proteins in aged mammals and humans with alzheimer's disease.the formation of clusters of altered axons and dendrites surrounding extracellular deposits of amyloid filaments (neuritic plaques) is a major feature of the human brain in both aging and alzheimer's disease. a panel of antibodies against amyloid filaments and their constituent proteins from humans with alzheimer's disease cross-reacted with neuritic plaque and cerebrovascular amyloid deposits in five other species of aged mammals, including monkey, orangutan, polar bear, and dog. antibodies to ...19873544219
comparative studies on soluble protein profiles and isozyme patterns of seven trichinella isolates.soluble protein profiles and isozyme patterns of eight enzymes were compared for extracts of muscle stage larvae of the seven trichinella isolates, using isoelectric focusing in polyacrylamide gel. soluble protein profiles and isozyme patterns of four enzymes: malic enzyme, glucosephosphate isomerase, phosphoglucomutase, superoxide dismutase of them were clearly divided into four types. t. pseudospiralis from a racoon and the polar strain from a polar bear formed type 1 and type 2. the iwasaki s ...19873615396
infectivity in rodents and cold resistance of trichinella spiralis isolated from pig and polar bear, and t. pseudospiralis. 19863723918
acyl coenzyme a:retinol acyltransferase activity and the vitamin a content of polar bear (ursus maritimus) liver.acyl coenzyme a:retinol acyltransferase activity was identified in the microsomes from a polar bear liver. the highest rate of in vitro retinol esterification was 821 pmol/min/mg microsomal protein. the in vitro esterification rate displayed a small dependence upon the concentration of exogenous protein (bovine serum albumin) and even less on the concentration of sulfhydryl-reducing agent (dithiothreitol). vitamin a was present in the liver at a concentration of 8050 micrograms/g tissue, with 98 ...19863757481
[primary structure of hemoglobin of the polar bear (ursus maritimus, carnivora) and the asiatic black bear (ursus tibetanus, carnivora].the adult polar and asiatic black bear have one hemoglobin component each. the complete amino-acid sequences of their alpha- and beta-chains are presented. their primary structures were determined by sequencing the tryptic and prolyl peptides. the alignment of these peptides was deduced from homology to human hemoglobin chains. the hemoglobin sequences of the two species proved to be identical. the evolutionary aspects of this result are discussed. a table of identical hemoglobin sequences from ...19863954890
heavy metals and essential elements in livers of the polar bear (ursus maritimus) in the canadian arctic.polar bear (ursus maritimus) livers (67) from six management zones in the western and central canadian arctic were analysed for 22 elements. several, ba, be, co, mo, ti, v and zr, were near the detection limit in all cases. baseline data were obtained for the remaining elements, ag, as, ca, cd, cu, fe, hg, k, mg, mn, na, p, se, sr and zn. no statistically significant effect of age, sex or geographical location was found for any of the elements, except cd, hg and se, for which age and geographica ...19863961478
editorial: trichinosis: from bismarck to polar bears. 19744406266
dermatitis caused by dermatophilus congolensis in polar bears (thalarctos maritimus). 19734721942
dermatitis caused by dermatophilus congolensis infection in polar bears (thalactos maritimus). 19725049481
electrolytes in tissues, red cells, and plasma of the polar bear and caribou. 19665905879
vitamin a content of polar bear liver. 19676036254
polar bear milk. 3. gel-electrophoretic studies of protein fractions isolated from polar bear milk and human milk. 19676064062
infectivity of isolates of trichinella and the ability of an arctic isolate to survive freezing temperatures in the raccoon, procyon lotor, under experimental conditions.the objectives of this study were to determine if the raccoon was a useful experimental animal for infections of trichinella and to determine if the ability of trichinella to survive freezing conditions, known to occur in wild animals, could be duplicated under laboratory conditions. the isolates of trichinella used in this study were from pigs, polar bear, wolverine, arctic fox and t. spiralis var. pseudospiralis originally isolated from a raccoon in the ussr. the raccoon was found to be a usef ...19836644931
comparison of three subspecies of trichinella spiralis by scanning electron microscopy.the surface morphology of three subspecies of trichinella spiralis was examined by sem in an attempt to find characteristics useful for distinguishing the subspecies. the subspecies studied were t. spiralis spiralis, which had been maintained in swine and laboratory animals for about 50 yr; t. spiralis nativa collected from ursus maritimus at 58 degrees n latitude and 95 degrees w longitude in 1976; and, t. spiralis pseudospiralis, which was derived from the original isolation of this subspecies ...19836674461
trichinella isolates from polar bears in svalbard. freeze resistance and infectivity in rats and swine.the author isolated trichinella strains from five polar bears in svalbard (the high arctic region of norway). based on infectivity experiments with white mice (bom:nmr), the freeze resistance limits of the trichinella strains are outlined. further experiments showed that white rats (mol:wist) and pigs (sus scrofa domestica) are almost refractory to these trichinella strains. the infectivity of svalbard isolates in the above mentioned test animals was compared, in parallel experiments, with that ...19846728674
interbreeding and gene flow in the genus trichinella.breeding experiments between isolates of trichinella spiralis--trichinella (pig; 43 degrees 00'n, 81 degrees 00'w; 1952), trichinella (polar bear; 58 degrees 00'n, 95 degrees 00'w; 1976), and trichinella (wolverine; 55 degrees 00'n, 100 degrees 00'w; 1979)--and t. spiralis var. pseudospiralis were undertaken. results from breeding experiments differed, such as the inability of the strain isolated from pigs and t. spiralis var. pseudospiralis to breed. the pig isolate was capable of breeding with ...19836827435
arctic terrestrial ecosystem contamination.limited data have been collected on the presence of contaminants in the arctic terrestrial ecosystem, with the exception of radioactive fallout from atmospheric weapons testing. although southern and temperate biological systems have largely cleansed themselves of radioactive fallout deposited during the 1950s and 1960s, arctic environments have not. lichens accumulate radioactivity more than many other plants because of their large surface area and long life span; the presence and persistence o ...19921355310
biological characteristics and host influence on a geographical isolate of trichinella (wolverine: 55 degrees 00'n, 100 degrees 00'w, 1979).biological characteristics of trichinella isolate (wolverine: 55 degrees 00'n, 100 degrees 00'w, 1979) were established in crl: cobs cfw (sw) mice. comparison of the wolverine isolate's biological characteristics with another trichinella isolate (polar bear), both from closely related geographic areas, revealed there were stable and reproducible genetic differences between isolates. differences were most pronounced for degree of infections causing a 50% mortality of mice, larval production by fe ...19827097442
designation and freezing resistance of isolates of trichinella spiralis from wild carnivores.a system to designate and define isolates of trichinella spiralis is proposed. the designation gives the host from which the isolate was recovered, geographic origin, and year of recovery. isolates of t. spiralis recovered from frozen muscles from four species of wild carnivores had low and different infectivity to laboratory mice. viable larvae of t. spiralis were obtained from muscle samples of marten, wolverine, polar bear and arctic fox which had been frozen for 5, 6, 12 and 14 mo, respectiv ...19827097881
baffin island medical experience includes polar bears, caribou hunt, eskimos. 19817231213
chemical attraction in the genus trichinella.chemical attraction in the genus trichinella was studied in vitro. male adult worms of trichinella spiralis, t. spiralis var. pseudospiralis, and trichinella sp. isolate (polar bear isolate) were attracted to females of their own isolates. the intensity of heterosexual chemical attraction between t. spiralis and the trichinella sp. isolate was similar, whereas t. spiralis var. pseudospiralis males were attracted less by either t. spiralis or the trichinella sp. isolate females. female worms of a ...19807365640
comparative anatomy of the cardiac foramen ovale in cats (felidae), dogs (canidae), bears (ursidae) and hyaenas (hyaenidae).the structure of the foramen ovale from 16 species representing 4 carnivore families, the felidae, canidae, ursidae and hyaenidae, was studied using the scanning electron microscope. the felidae were represented by 9 domestic cat fetuses (felis catus), 2 snow leopard neonates (uncia uncia), an ocelot neonate (leopardus pardalis), 2 lion neonates (panthera leo), a panther neonate (panthera pardus) and 3 tigers (neofelis tigris), comprising 2 fetuses and a neonate. the canidae were represented by ...19957649822
phylogenetic relationships of bears (the ursidae) inferred from mitochondrial dna sequences.the phylogenetic relationships among some bear species are still open questions. we present here mitochondrial dna sequences of d-loop region, cytochrome b, 12s rrna, trna(pro), and trna(thr) genes from all bear species and the giant panda. a series of evolutionary trees with concordant topology has been derived based on the combined data set of all of the mitochondrial dna sequences, which may have resolved the evolutionary relationships of all bear species: the ancestor of the spectacled bear ...19947697192
catalytic and immunologic characterization of hepatic and lung cytochromes p450 in the polar bear.the arctic ocean is subject to considerable influx of anthropogenic pollutants including halogenated organic compounds. the polar bear (ursus maritimus) is at the top of the arctic marine food web and is an ideal species for monitoring the level and distribution of contaminants in the arctic ecosystem. as the first step in the development of a biological method for assessing the functional exposure of polar bears to xenobiotics, biochemical studies were undertaken to characterize polar bear cyto ...19957748195
inuit exposure to organochlorines through the aquatic food chain in arctic québec.inuit people (eskimos) are likely exposed to persistent organochlorine compounds because their traditional diet includes fatty tissues of the arctic marine biota. here we present the results of organochlorine compound analysis in milk fat samples from arctic québec inuit women and in fat tissues from various animal species inhabiting that region. the total concentration of polychlorinated biphenyl congeners in inuit milk fat was similar to that of the beluga, while the profile of the 10 congener ...19938143594
ursodeoxycholic acid in the ursidae: biliary bile acids of bears, pandas, and related carnivores.the biliary bile acid composition of gallbladder bile obtained from six species of bears (ursidae), the giant panda, the red panda, and 11 related carnivores were determined by reversed phase liquid chromatography and gas chromatography-mass spectrometry. bile acids were conjugated solely with taurine (in n-acyl linkage) in all species. ursodeoxycholic acid (3 alpha, 7 beta-dihydroxy-5 beta-cholan-24-oic acid) was present in all ursidae, averaging 1-39% of biliary bile acids depending on the spe ...19938263415
a beta-associated cerebral angiopathy and senile plaques with neurofibrillary tangles and cerebral hemorrhage in an aged wolverine (gulo gulo).in this study of an aged wolverine (gulo gulo), we document neuropathologic lesions (cerebral amyloid angiopathy (caa), neuritic plaques (nps), neurofibrillary tangles (nfts), and granulovacuolar degeneration strikingly similar to those present in aging and alzheimer's disease (ad), with the additional finding of concurrent cerebral hemorrhage. a beta immunoreactive cerebral amyloid angiopathy and senile plaques (neuritic and diffuse) were present throughout the cerebral cortex and hippocampus. ...19968744405
carboxy terminal of beta-amyloid deposits in aged human, canine, and polar bear brains.immunocytochemistry, using antibodies specific for different carboxy termini of beta-amyloid. a beta 40 and a beta 42(43), was used to compare beta-amyloid deposits in aged animal models to nondemented and demented alzheimer's disease human cases. aged beagle dogs exhibit diffuse plaques in the absence of neurofibrillary pathology and the aged polar bear brains contain diffuse plaques and phf-1-positive neurofibrillary tangles. the brains of nondemented human subjects displayed abundant diffuse ...19968744406
phylogeography of brown bears (ursus arctos) of alaska and paraphyly within the ursidae.complete nucleotide sequences of the mitochondrial cytochrome b, trna(prolime), and trna(threonine) genes were described for 166 brown bears (ursus arctos) from 10 geographic regions of alaska to describe natural genetic variation, construct a molecular phylogeny, and evaluate classical taxonomies. dna sequences of brown bears were compared to homologous sequences of the polar bear (maritimus) and of the sun bear (helarctos malayanus), which was used as an outgroup. parsimony and neighbor-joinin ...19968744762
a phylogeny of the bears (ursidae) inferred from complete sequences of three mitochondrial genes.complete sequences of dna are described for the cytochrome b trna(thr) and trna(pro) genes of mitochondria of four extant species of ursids and compared to sequences of four other species of ursids previously studied by us. phylogenetic analyses indicate that the giant panda and the spectacled bear are the basal taxa of the ursid radiation. the ursines, a group which includes the sun bear, sloth bear, american black bear, asiatic black bear, brown bear, and polar bear, experienced a rapid radiat ...19968744769
serological evidence of morbillivirus infection in polar bears (ursus maritimus) from alaska and russia.one-hundred-and-ninety-one samples of blood serum collected from 186 polar bears (ursus maritimus) between 1987 and 1992 were analysed for morbillivirus antibodies. the samples were collected in the bering, chukchi and east siberian seas. sixty-eight samples (35.6 per cent) had morbillivirus antibody titres > 5; the percentage of positive samples ranged from 26.2 to 46.2 per cent from year to year. the proportions of adults, sub-adults and cubs which were seropositive were 43.9, 35.7 and 37.9 pe ...19968807784
estimation of accumulated dose of radiation by the method of esr-spectrometry of dental enamel of mammals.esr-spectrometry was used to investigate radiation-induced paramagnetic centers in enamel of mammals: carnivores (polar bear and fox), ungulates (reindeer, european bison, moose), and man. values at half the microwave power saturation of the radiation signal, p1/2, evaluated at room temperature, was found to range from 16 to 26 mw for animals and man. a new approach to discrimination of the radiation induced signal from the total esr spectrum of reindeer enamel is proposed. 'dose-response' depen ...19969022192
immunoquantitation of cytochromes p450 1a and p450 2b and comparison with chlorinated hydrocarbon levels in archived polar bear liver samples.the present study examined the utility of an immunoblot method for quantitation of cytochrome p450 isozymes in archived liver samples as a bioassay of exposure to halogenated hydrocarbons. hepatic microsomes were prepared from 44 archived polar bear (ursus maritimus) liver homogenates that had been stored at approximately -40 degrees c for 9-10 years and analyzed on blots probed with antibodies to rat cytochromes p450 1a1 and p450 2b1. the results revealed a positive correlation between cytochro ...19979134680
fatal hepatic sarcocystosis in two polar bears (ursus maritimus).fatal hepatic sarcocystosis was diagnosed in 2 polar bears from a zoo in anchorage, alaska. gross lesions were icterus and systemic petechiae. marked microscopic lesions were detected only in the liver and included severe random necrotizing hepatitis with hemorrhage. only asexual stages of an apicomplexan parasite were detected within hepatocytes, and rare extracellular zoites were seen in foci of necrosis. the parasite divided by endopolygeny, and occasionally merozoites formed rosettes around ...19979194839
acute chagas' cardiopathy in a polar bear (ursus maritimus) in guadalajara, mexico.we report a 24-year-old female polar bear (ursus maritimus) who contracted chagas' infection at the guadalajara zoo, in jalisco, méxico, and died of acute chagas' carditis 15 days later. the histopathological findings are described, as well as the presence of triatomids (triatoma longipennis usinger) infected with trypanosoma cruzi collected within 5 meters from the place where the animal lived in the city of guadalajara.19979219444
identification and differentiation of bear bile used in medicinal products in taiwan.one hundred eighty-three suspect bear bile used in medicinal products, collected in taiwan as gall bladders or dried powder forms, were analyzed using ftir, hptlc, and hplc techniques to identify whether they are indeed bear bile. those confirmed were further examined to determine whether the observed analytical parameters can be reliably used for source inference, i.e., differentiating products among north american black bear, farmed asiatic black bear, polar bear, etc. our data suggested that ...19979304828
n-terminal heterogeneity of parenchymal and cerebrovascular abeta deposits.the goals of this study were twofold: to determine whether species differences in abeta n-terminal heterogeneity explain the absence of neuritic plaques in the aged dog and aged bear in contrast to the human; and to compare abeta n-terminal isoforms in parenchymal vs cerebrovascular abeta (cva) deposits in each of the species, and in individuals with alzheimer disease (ad) vs nondemented individuals. n-terminal heterogeneity can affect the aggregation, toxicity, and stability of abeta. the human ...19989600199
trichinella in arctic, subarctic and temperate regions: greenland, the scandinavian countries and the baltic states.the transmission and occurrence of trichinella spp according to the zoogeography of different climatic conditions, socioeconomy and human activity are discussed. comparing arctic, subarctic and temperate regions, it appears that the species of trichinella present, the composition of the fauna and the human activity are all very important interacting factors affecting epidemiology. in greenland, where only sylvatic trichinellosis is present, the high prevalence in wildlife appears closely connect ...19979656341
female pseudohermaphrodite polar bears at svalbard.during research on polar bears (ursus maritimus) at svalbard in april 1996, we captured two yearlings with a normal vaginal opening and a 20 mm penis containing a baculum. the penis was located caudal to the location in a normal male and was concealed within the vaginal opening by a single pair of labia. the urethral opening was situated laterally about 5 mm from the distal end of the penis. neither of the yearlings showed signs of a y chromosome, so both bears were regarded as female pseudoherm ...19989813850
man and polar bear in svalbard: a solvable ecological conflict?the objective of this study is twofold. first, it is to assess the nature and magnitude of the polar bear-human conflict with respect to injuries to man and bear. second, a major concern has been to minimize injurious interactions in order to safeguard the people who live and work in the arctic, and, at the same time, secure the future of the polar bear in one of the last relatively unspoiled habitats on earth for big carnivores. from 1971 to 1995, approximately 80 bears were involved in serious ...199810093337
localization and comparative toxicity of methylsulfonyl-2,5- and 2,6-dichlorobenzene in the olfactory mucosa of mice.several methylsulfonyl (meso2) metabolites formed from chlorinated aromatic hydrocarbons have been identified in human milk, lung, and body fat, as well as in the tissues of baltic grey seals and arctic polar bears. the tissue localization and nasal toxicity of two methylsulfonyl-substituted dichlorobenzenes (dicl-meso2-b), with the chlorine atoms in the 2,5-, and 2,6- positions, were investigated in female nmri and c57b1 mice. using tape-section autoradiography, animals dosed i.v. with 14c-labe ...199910367349
bear-inflicted human injury and fatality.this review attempts to summarize credible scientific information, and to dispel myths, regarding bear attacks. publications in the scientific literature were sought through a medline search and by reviewing the bibliographies of related books and scientific articles. personal experience and interviews with authorities were also used in preparation of this review, although only published articles or books are cited. this is a summary of case series reported or observed elsewhere. bear-inflicted ...199910442155
comparative anatomy of the radial sesamoid bone in the polar bear (ursus maritimus), the brown bear (ursus arctos) and the giant panda (ailuropoda melanoleuca).since we have clarified the manipulation mechanism using the radial sesamoid (rs) in the giant panda (ailuropoda melanoleuca), our aim in this study is to examine the position, shape and function of the rs morphologically, and to observe the attachment to the rs of the m. abductor pollicis longus and the m. opponens pollicis in the other ursidae species. so, we focused on the carpus and manus of the polar bear (ursus maritimus) and the brown bear (ursus arctos) in this study. the rs was tightly ...199910487229
aujeszky's disease in captive bears.five of eight bears died during an outbreak of aujeszky's disease in a travelling circus in the north of spain. the bears had been fed on a diet which included raw pigs' heads. one of three himalayan bears and a kodiak bear died acutely with signs of the disease. one of four polar bears died acutely without signs, another died with signs of aujeszky's disease while it was being treated, and a third died with enteritis and disseminated intestinal coagulation some time later without showing signs ...199910573192
absence of trypanosomes in polar bears (ursus maritimus) from svalbard. 199910576628
genetic structure of the world's polar bear populations.we studied genetic structure in polar bear (ursus maritimus) populations by typing a sample of 473 individuals spanning the species distribution at 16 highly variable microsatellite loci. no genetic discontinuities were found that would be consistent with evolutionarily significant periods of isolation between groups. direct comparison of movement data and genetic data from the canadian arctic revealed a highly significant correlation. genetic data generally supported existing population (manage ...199910583821
acute fish liver intoxication: report of three cases.the livers of some larger fish such as shark, tuna and seabass have been reported to be responsible for a peculiar poisoning causing headaches and desquamation. this type of poisoning can also be induced by ingestion of the livers of the sea whale, the polar bear and the seal. since these animals contain an extremely large quantity of vitamin a in their livers and the symptoms of poisoning in the patients resembled those of patients with acute hypervitaminosis a, the poisoning was believed to ha ...199910584420
cloning and sequence analysis of the extracellular region of the polar bear (ursus maritimus) luteinizing hormone receptor (lhr), follicle stimulating hormone receptor (fshr), and prolactin receptor (prlr) genes and their expression in the testis of the black bear (ursus americanus).male black bears undergo seasonal changes in testicular activity. the testes are fully functional from may through july, regress from july through december, and recrudesce from january until may. the mechanisms responsible for the initiation of testicular recrudescence in the bear are unknown. the objectives of this study were to: (1) clone and sequence a substantial fragment of the extracellular portion of the luteinizing hormone receptor (lhr: 646 bp) and follicle stimulating hormone receptor ...200010618652
autochthonous and imported trichinella isolates in germany.the study of trichinella isolates from wildlife in germany revealed the presence of trichinella spiralis and trichinella britovi in wild boars and foxes. t spiralis was detected in meat products imported from spain, which is one of the two endemic areas of domestic trichinellosis in the european union: it was also detected in meat from a grizzly bear marketed in alaska, and trichinella nativa was detected in a polar bear from the berlin zoo. these results stress the importance of examining for t ...200010622607
adaptation of the muscles of mastication to the flat skull feature in the polar bear (ursus maritimus).the muscles of mastication of the polar bear (ursus maritimus) and those of the brown bear (u. arctos) were examined by anatomical approach. in addition, the examination of the skull was carried out in the polar bear, brown bear and giant panda (ailuropoda melanoleuca). in the polar bear, the rostro-ventral part of the superficial layer of the m. masseter possessed the abundant fleshy portion folded in the rostral and lateral directions like an accordion. moreover, the rostro-medial area of the ...200010676883
geographical differences of zinc, cadmium, mercury and selenium in polar bears (ursus maritimus) from greenland.muscle, liver, and kidney tissues from 100 polar bears (ursus maritimus), caught in the avanersuaq area, north-west greenland, and ittoqqortoormiit area, central-east greenland, were analysed for zinc, cadmium, mercury and selenium. the zinc concentrations in muscle and liver were higher than in kidney. mean zinc concentrations ranged from 19.7 to 76.0 micrograms/g (all data are presented as geometric means on a wet wt. basis). the presented cadmium concentrations by area and age groups were all ...200010682354
temporal and spatial trends of persistent organochlorines in greenland walrus (odobenus rosmarus rosmarus).persistent organochlorines [pcbs, ddt and chlordane related compounds, dieldrin, toxaphene, hexachlorocyclohexane (hch), chlorobenzenes] were determined in blubber of atlantic walrus (odobenus rosmarus rosmarus) in 1978 and 1988 from the avanersuaq (thule) region of north-west greenland and in 1989 from ittoqqortoormiit (scoresbysund) in east greenland. lowest concentrations of organochlorines (ocs) were found in the samples from the avanersuaq region while much higher levels of all compounds, e ...200010682357
organochlorines in top predators at svalbard--occurrence, levels and effects.alarmingly high polychlorinated biphenyl (pcb) levels have been found in the top predators such as glaucous gull (larus hyperboreus) and polar bear (ursus maritimus) at svalbard [gabrielsen, g.w., skaare, j.u., polder, a., bakken, v., 1995. chlorinated hydrocarbons in glaucous gull (larus hyperboreus). sci. total environ. 160/161, 337-346; bernhoft, a., skaare, j.u., wiig, o., 1997. organochlorines in polar bears (ursus maritimus) at svalbard. environ. pollut. 95, 159-175; henriksen, e.o., gabri ...200010720718
possible immunotoxic effects of organochlorines in polar bears (ursus maritimus) at svalbard.associations between immunoglobulin g (igg) levels and the organochlorine contaminants (ocs) polychlorinated biphenyls (pcbs), chlordanes, 1,1-dichloro-2,2-bis(4-chlorophenyl) ethylene (dde), hexachlorobenzene (hcb), and hexachlorocyclohexanes (hchs) in blood plasma from polar bears caught at svalbard were determined. the blood samples were collected from free-living polar bears of different age and sex between 1991 and 1994. the igc concentration increased with age and was significantly higher ...200010777247
phylogeography of mitochondrial dna variation in brown bears and polar bears.we analyzed 286 nucleotides of the middle portion of the mitochondrial cytochrome b gene of 61 brown bears from three locations in alaska and 55 polar bears from arctic canada and arctic siberia to test our earlier observations of paraphyly between polar bears and brown bears as well as to test the extreme uniqueness of mitochondrial dna types of brown bears on admiralty, baranof, and chichagof (abc) islands of southeastern alaska. we also investigated the phylogeography of brown bears of alaska ...200010837161
2,3-dpg-hb complex: a hypothesis for an asymmetric binding.this study was undertaken to test the symmetry of 2,3-diphosphoglycerate (2,3-dpg) binding site in hemoglobin (hb). from arnone's study [a. arnone, nature (london) 237 (1972) 146] the 2,3-dpg binding site is located at the top of the cavity, that runs through the center of the deoxy-hb molecule. however, it is possible that this symmetry reported by arnone, for crystals of 2,3-dpg-hb complex, might not be conserved in solution. in this paper, we report the 31p nuclear magnetic resonances of the ...200010852312
chemical characterization of milk oligosaccharides of the polar bear, ursus maritimus.two trisaccharides, three tetrasaccharides, two pentasaccharides, one hexasaccharide, one heptasaccharide, one octasaccharide and one decasaccharide were isolated from polar bear milk samples by chloroform/methanol extraction, gel filtration, ion exchange chromatography and preparative thin-layer chromatography. the oligosaccharides were characterized by 1h-nmr as follows: the saccharides from one animal: gal(alpha1-3)gal(beta1-4)glc (alpha3'-galactosyllactose), fuc(alpha1-2)gal(beta1-4)glc (2'- ...200010913842
pharmacokinetics and tissue residues of telazol in free-ranging polar bears.a pharmacokinetic and tissue residue study was conducted to assess the risks associated with human consumption of polar bears in arctic canada that have been exposed to the immobilizing drug telazol, a mixture of tiletamine hydrochloride and zolazepam hydrochloride. twenty-two bears were remotely injected with about 10 mg/kg of telazol. following immobilization, serum samples were collected serially at regular intervals until the bears awakened. sixteen of the bears were relocated and killed und ...200011085426
the occurrence and ecology of trichinella in marine mammals.trichinella in marine mammals has a circumpolar arctic distribution and a narrow range of host species. it is commonly found in polar bears (ursus maritimus), and increasingly in walruses (odobenus rosmarus) where it presents a significant zoonotic hazard. this has resulted in the implementation of food safety programs in some arctic communities to test harvested walrus meat for trichinella larvae prior to consumption. trichinella has been reported infrequently in bearded seals (erignathus barba ...200011099845
serum concentrations of vitamin d metabolites, vitamins a and e, and carotenoids in six canid and four ursid species at four zoos.nutritional status for six captive canid species (n=34) and four captive ursid species (n=18) were analyzed. the species analyzed included: african wild dog (lycaon pictus), arctic fox (alopex lagopus), gray wolf (canis lupus), maned wolf (chrysocyon brachyurus), mexican wolf (canis lupus baleiyi), red wolf (canis rufus), brown bear (ursus arctos), polar bear (ursus maritimus), spectacled bear (tremarctos ornatus), and sun bear (ursus malayanus). diet information was collected for these animals ...200111137448
relationships between plasma levels of organochlorines, retinol and thyroid hormones from polar bears (ursus maritimus) at svalbard.associations were determined between retinol and the thyroid hormones thyroxine (t4) and triiodothyronine (t3), respectively, and the organochlorine contaminants (ocs) polychlorinated biphenyls (pcbs), 1, 1-dichloro-2,2-bis-(4-chlorophenyl)ethylene (dde), hexachlorobenzene (hcb), and hexachlorocyclohexanes (hchs) in blood plasma from polar bears (ursus maritimus) caught at svalbard. the blood samples were collected from free-ranging polar bears of different age and sex in 1991-1994. the retinol ...200111245393
nuclear deviation in hepatic parenchymal cells on sinusoidal surfaces in arctic animals.in normal rat and human, most of the nuclei of hepatic parenchymal cells are centrally located in the cytoplasm. however, it is reported that the nuclei of hepatic parenchymal cells are situated at a deviated position on sinusoidal surfaces under pathological situations such as chronic hepatitis, hepatocellular carcinoma, adenomatous hyperplasia, or regeneration. during a study on the mechanism of extreme vitamin a-accumulation in hepatic stellate cells of arctic animals including polar bears, a ...200111482455
ultrastructural characteristics of nurse cell-larva complex of four species of trichinella in several hosts.the nurse cell-larva complex of nematodes of the genus trichinella plays an important role in the survival of the larva in decaying muscles, frequently favouring the transmission of the parasite in extreme environmental conditions. the ultrastructure of the nurse cell-larva complex in muscles from different hosts infected with t. nativa (a walrus and a polar bear), t. spiralis (horses and humans), t. pseudospiralis (a laboratory mouse) and t. papuae (a laboratory mouse) were examined. analysis w ...200111484383
brucella sp. antibodies in polar bears from svalbard and the barents sea.a prevalence of 5.4% of anti-brucella sp. antibodies was found in plasma samples from 297 polar bears (ursus maritimus) from svalbard and the barents sea. plasma was tested by the classical brucellosis tests slow agglutination of wright (saw), edta modified saw and rose bengal test, as well as by an indirect protein a elisa. only samples classified as positive in all tests were regarded as containing anti-brucella sp. antibodies. a significant west to east increase in the proportion of bears wit ...200111504225
bear mauling: a descriptive review.provide a descriptive review of bear and human interactions in the united states.200111768451
commentary: abeta n- terminal isoforms: critical contributors in the course of ad pathophysiology.the assessment of protein or amino acid variations across evolution allows one to glean divergent features of disease-specific pathology. within the alzheimer's disease (ad) literature, extensive differences in abeta processing across cell lines and evolution have clearly been observed. in the recent past, increased levels of amyloid beta abeta1-42 have been heralded to be what distinguishes whether one is prone to the development of ad [59]. however, observations in naturally occurring, non-tra ...200112214065
plasma biochemical values from apparently healthy free-ranging polar bears from svalbard.to establish reference values for free-ranging polar bears (ursus maritimus) at svalbard, norway, plasma samples from 15 females and 20 males were analyzed for 28 blood biochemistry parameters. animals were chemically immobilized (zoletil: tiletamine and zolazepam) on land at barentsøya, edgeøya, and the eastern coast of spitsbergen in august 1998. all bears were apparently healthy, with ages ranging from 1-22 yr. females had almost two times higher levels of lipase than males. several parameter ...200212238374
emerging morbillivirus infections of marine mammals: development of two diagnostic approaches.in the last 13 years, four viruses belonging in the morbillivirus genus of the paramyxoviridae family have emerged as significant causes of disease and mortality in marine mammals. the viruses involved are canine distemper virus (cdv) in seals and polar bears, dolphin morbillivirus (dmv) and porpoise morbillivirus (pmv) in cetaceans, and phocine distemper virus (pdv) in pinnipeds. the two cetacean morbilliviruses (dmv and pmv) are now considered to be the same viral species, named cetacean morbi ...200212381563
polar bear hemoglobin and human hb a0: same 2,3-diphosphoglycerate binding site but asymmetry of the binding?polar bear (ursus maritimus) hemoglobin (hb) shows a low response to 2,3-diphosphoglycerate (2,3-dpg), compared to human hb a0, even though these proteins have the same 2,3-dpg-binding site. in addition, polar bear hb shows a high response to chloride and an alkaline bohr effect (deltalog p50/deltaph) that is significantly greater than that of human hb a0. the difference in sequence pro (hb a0)-->gly (polar bear hb) at position a2 in the a helix seems to be critical for reduced binding of 2,3-dp ...200212484631
contaminants in svalbard polar bear samples archived since 1967 and possible population level effects.blood plasma samples were collected in 1967 from 32 polar bears (ursus maritimus) in eastern svalbard. these samples were stored frozen until 2001 and then analyzed for 33 polychlorinated biphenyls (pcb), two toxaphene congeners, ddts, chlordanes (chl), hexachlorobenzene, hexachlorocyclohexanes (hchs), and polybrominated flame retardants (biphenyls and diphenyl ethers). the 1967 pollutant levels were compared with values from 1993 to 1994 for adult females and adult males to obtain insights into ...200312493194
distribution of vitamin a-storing lipid droplets in hepatic stellate cells in liver lobules--a comparative study.to investigate the storage mechanisms of vitamin a, we examined the liver of adult polar bears and arctic foxes, which physiologically store a large amount of vitamin a, by high-performance liquid chromatography (hplc), transmission electron microscopy (tem) morphometry, gold chloride staining, fluorescence microscopy for the detection of autofluorescence of vitamin a, staining with hematoxylin-eosin (h&e), masson's trichrome, and ishii and ishii's silver impregnation. hplc revealed that the pol ...200312552640
cerebral arteriosclerosis in an aged captive polar bear (ursus maritimus).cerebral arteriosclerosis was observed upon necropsy of a 36-yr-old female captive polar bear (ursus maritimus) that developed a sudden onset of seizure-like activity and died. the medium and large cerebral arteries of the meninges had moderate to severe diffuse discoloration and mineralization of the matrix of the tunica media, with little or no associated cellular reaction. scanning electron microscopy of the affected arteries showed discrete crystalline calcified deposits in the media and scl ...200212564538
comparison of seven blastomyces dermatitidis antigens for the detection of antibodies in humans with occupationally acquired blastomycosis.yeast phase lysate antigens, prepared from seven isolates of blastomyces dermatitidis (dogs, t-58, m-98; human, le; soil, s; sea lion, sl; polar bear, pb; cat, c) were assayed by enzyme-linked immunosorbent assay (elisa) to detect antibodies in human sera. the sera were from individuals potentially exposed to b. dermatitidis while working on a prairie dog relocation project in colorado. all antigens exhibited greatest reactivity with three specimens in two separate assays. absorbance values rang ...200212572716
geographical distribution of organochlorine pesticides (ocps) in polar bears (ursus maritimus) in the norwegian and russian arctic.geographical variation of organochlorine pesticides (ocps) was studied in blood samples from 90 adult female polar bear (ursus maritimus) from svalbard, franz josef land, kara sea, east-siberian sea and chukchi sea. in all regions, oxychlordane was the dominant ocp. regional differences in mean levels of hcb, oxychlordane, trans-nonachlor, alpha-hch, beta-hch and p,p'-dde were found. the highest levels of oxychlordane, trans-nonachlor and dde were found in polar bears from franz josef land and k ...200312699924
glycero- versus sphingo-phospholipids: correlations with human and non-human mammalian lens growth.the human lens differs from other mammalian lenses in its very slow growth and unusual phospholipid composition of its cell membranes. dihydrosphingomyelins (dhsms) make up about half of all phospholipids in adult human fiber membranes. in all other membranes, sphingomyelins(sms) with a trans double bond in their backbone, are prevalent. in our quest to understand the biological implications of such elevated dhsm levels, we analyzed membranes from various regions of human, elephant, giraffe, pol ...200312742355
distribution of methyl sulfone metabolites of polychlorinated biphenyls and p,p'-dde in human tissues.we determined methylsulfonyl metabolites of chlorinated biphenyls (meso2-cbs) and 1,1-bis(4-chlorophenyl)-2,2-dichloroethene (p,p'-dde) in human adipose, liver, brain, and lung tissues obtained from 11 belgian individuals (9-62 years of age). the total concentration of meso2-cbs (lipid weight basis) decreased in the following order: liver (mean, 9.30 ng/g; range, 1.68-27.03 ng/g lipid) > lung [mean, 2.72 ng/g; range, not detected (nd) to 11.54 ng/g lipid] > adipose tissue (mean, 1.57 ng/g; range ...200312842777
differences in oligosaccharide pattern of a sample of polar bear colostrum and mid-lactation milk.although the concentrations of carbohydrate in the colostrum and in the mid-lactation milk of polar bear (ursus maritimus) were similar, the oligosaccharide patterns differed. the colostrum sample contained neu5ac(alpha2-3)gal(beta1-4)glc (3'-n-acetylneuraminyllactose), galnac(alpha1-3)[fuc(alpha1-2)]gal(beta1-4)glc (a-tetrasaccharide), fuc(alpha1-2)gal(beta1-4)glc (2'-fucosyllactose) and gal(beta1-4)glc (lactose). the mid-lactation milk contained gal(alpha1-3)[fuc(alpha1-2)]gal(beta1-4)[fuc(alp ...200314662310
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