Resistance of a rodent malaria parasite to a thymidylate synthase inhibitor induces an apoptotic parasite death and imposes a huge cost of fitness.

Science.gov (United States)

Muregi, Francis W; Ohta, Isao; Masato, Uchijima; Kino, Hideto; Ishih, Akira

2011-01-01

The greatest impediment to effective malaria control is drug resistance in Plasmodium falciparum, and thus understanding how resistance impacts on the parasite's fitness and pathogenicity may aid in malaria control strategy. To generate resistance, P. berghei NK65 was subjected to 5-fluoroorotate (FOA, an inhibitor of thymidylate synthase, TS) pressure in mice. After 15 generations of drug pressure, the 2% DT (the delay time for proliferation of parasites to 2% parasitaemia, relative to untreated wild-type controls) reduced from 8 days to 4, equalling the controls. Drug sensitivity studies confirmed that FOA-resistance was stable. During serial passaging in the absence of drug, resistant parasite maintained low growth rates (parasitaemia, 15.5%±2.9, 7 dpi) relative to the wild-type (45.6%±8.4), translating into resistance cost of fitness of 66.0%. The resistant parasite showed an apoptosis-like death, as confirmed by light and transmission electron microscopy and corroborated by oligonucleosomal DNA fragmentation. The resistant parasite was less fit than the wild-type, which implies that in the absence of drug pressure in the field, the wild-type alleles may expand and allow drugs withdrawn due to resistance to be reintroduced. FOA resistance led to depleted dTTP pools, causing thymineless parasite death via apoptosis. This supports the tenet that unicellular eukaryotes, like metazoans, also undergo apoptosis. This is the first report where resistance to a chemical stimulus and not the stimulus itself is shown to induce apoptosis in a unicellular parasite. This finding is relevant in cancer therapy, since thymineless cell death induced by resistance to TS-inhibitors can further be optimized via inhibition of pyrimidine salvage enzymes, thus providing a synergistic impact. We conclude that since apoptosis is a process that can be pharmacologically modulated, the parasite's apoptotic machinery may be exploited as a novel drug target in malaria and other protozoan

Parasites of domestic and wild animals in South Africa. XLVIII . Ticks (Acari: Ixodidae infesting domestic cats and wild felids in southern Africa

Directory of Open Access Journals (Sweden)

Ivan G. Horak

2010-11-01

Full Text Available Ticks collected from domestic cats (Felis catus, cheetahs (Acinonyx jubatus,caracals (Caracal caracal, African wild cats (Felis lybica, black-footed cats (Felis nigripes, a serval (Leptailurus serval, lions(Panthera leo, and leopards (Panthera pardus were identified and counted. Thirteen species of ixodid ticks and one argasid tick were identified from domestic cats and 17 species of ixodid ticks from wild felids. The domestic cats and wild felids harboured 11 ixodid species in common. The adults of Haemaphysalis elliptica, the most abundant tick species infesting cats and wild felids, were most numerous on a domestic cat in late winter and in mid-summer, during 2 consecutive years. The recorded geographic distribution of the recently described Haemaphysalis colesbergensis, a parasite of cats and caracals, was extended by 2 new locality records in the Northern Cape Province,South Africa.

DNA vaccines encoding proteins from wild-type and attenuated canine distemper virus protect equally well against wild-type virus challenge.

Science.gov (United States)

Nielsen, Line; Jensen, Trine Hammer; Kristensen, Birte; Jensen, Tove Dannemann; Karlskov-Mortensen, Peter; Lund, Morten; Aasted, Bent; Blixenkrone-Møller, Merete

2012-10-01

Immunity induced by DNA vaccines containing the hemagglutinin (H) and nucleoprotein (N) genes of wild-type and attenuated canine distemper virus (CDV) was investigated in mink (Mustela vison), a highly susceptible natural host of CDV. All DNA-immunized mink seroconverted, and significant levels of virus-neutralizing (VN) antibodies were present on the day of challenge with wild-type CDV. The DNA vaccines also primed the cell-mediated memory responses, as indicated by an early increase in the number of interferon-gamma (IFN-γ)-producing lymphocytes after challenge. Importantly, the wild-type and attenuated CDV DNA vaccines had a long-term protective effect against wild-type CDV challenge. The vaccine-induced immunity induced by the H and N genes from wild-type CDV and those from attenuated CDV was comparable. Because these two DNA vaccines were shown to protect equally well against wild-type virus challenge, it is suggested that the genetic/antigenic heterogeneity between vaccine strains and contemporary wild-type strains are unlikely to cause vaccine failure.

Fish parasites

DEFF Research Database (Denmark)

This book contains 22 chapters on some of the most important parasitic diseases in wild and farmed fish. International experts give updated reviews and provide solutions to the problems......This book contains 22 chapters on some of the most important parasitic diseases in wild and farmed fish. International experts give updated reviews and provide solutions to the problems...

A coprological survey of intestinal parasites of wild lions (Panthera leo) in the Serengeti and the Ngorongoro Crater, Tanzania, east Africa.

Science.gov (United States)

Müller-Graf, C D

1995-10-01

Fecal examination on 112 and a subset of 58 wild lions (Panthera leo) in the Serengeti National Park and the Ngorongoro Crater, Tanzania, East Africa revealed eggs, larvae, and protozoan cysts of 15 parasite taxa. The most prevalent were Spirometra sp. (63% prevalence), Taeniidae (58%), Ancylostoma sp. (56%), and a coccidian (53%). Three parasites were considered spurious. Of the hosts, 97.3% were infected with at least 1 species of parasite. Individual parasite taxa were aggregated among hosts.

The role of wild canids and felids in spreading parasites to dogs and cats in Europe. Part II: Helminths and arthropods.

Science.gov (United States)

Otranto, Domenico; Cantacessi, Cinzia; Dantas-Torres, Filipe; Brianti, Emanuele; Pfeffer, Martin; Genchi, Claudio; Guberti, Vittorio; Capelli, Gioia; Deplazes, Peter

2015-09-30

Over the last few decades, ecological factors, combined with everchanging landscapes mainly linked to human activities (e.g. encroachment and tourism) have contributed to modifications in the transmission of parasitic diseases from domestic to wildlife carnivores and vice versa. In the first of this two-part review article, we have provided an account of diseases caused by protozoan parasites characterised by a two-way transmission route between domestic and wild carnivore species. In this second and final part, we focus our attention on parasitic diseases caused by helminth and arthropod parasites shared between domestic and wild canids and felids in Europe. While a complete understanding of the biology, ecology and epidemiology of these parasites is particularly challenging to achieve, especially given the complexity of the environments in which these diseases perpetuate, advancements in current knowledge of transmission routes is crucial to provide policy-makers with clear indications on strategies to reduce the impact of these diseases on changing ecosystems. Copyright © 2015 Elsevier B.V. All rights reserved.

Occurrence of gastrointestinal parasites in wild animals in State of Paraná, Brazil.

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Sprenger, Lew K; Yoshitani, Ursula Y; Buzatti, Andreia; Molento, Marcelo B

2018-01-01

The objective of this study was to determine the prevalence and diversity of gastrointestinal parasites in fecal samples from wild birds and mammals from the State of Paraná. In total, 220 stool samples were sent to Parasitic Diseases Laboratory of the Federal University of Paraná during 13 months (Jan/2013-Jan/2014). A total of 52.7% (116/220) of the animals were positive for cysts, oocysts, eggs and/or trophozoites. In birds, the positivity rate was 37.9% (25/66) and mammals was 59.1% (91/154). Strongyloidea superfamily eggs were observed in 37.3% (82/220) of the samples, Eimeria spp. in 10% (22/220), and Trichuris spp. in 4.5% (10/220). The most frequent mammal species were llamas (Lama glama), and dromedaries (Camelus bactrianus) with infection rate of 70.1% (54/77) and 60.8% (14/23), respectively. In other hand, cockatiels (Nymphicus hollandicus) and ring necks (Psittacula krameri), were the most researched birds, with infection rate of 20% (40/50) and 100% (6/6), respectively. A high prevalence of gastrointestinal parasites was observed in most of wildlife animals. Further investigations should be conducted focusing on parasite control strategies and the conservation measurements for harmonizing the human-animal interaction on the long-term, reducing associated health risks.

Assessment of gastrointestinal parasites in wild chimpanzees (Pan troglodytes troglodytes) in southeast Cameroon.

Science.gov (United States)

Drakulovski, Pascal; Bertout, Sébastien; Locatelli, Sabrina; Butel, Christelle; Pion, Sébastien; Mpoudi-Ngole, Eitel; Delaporte, Eric; Peeters, Martine; Mallié, Michèle

2014-07-01

We tested 114 faecal samples from wild simian immunodeficiency virus (SIV)-positive (n = 43) and SIV-negative (n = 71) chimpanzees (Pan troglodytes troglodytes) in southeast Cameroon for the presence of gastrointestinal parasites by direct smear. We observed cysts from different protozoa (Entamoeba coli and Entamoeba histolytica / Entamoeba dispar, Endolimax nana, Iodamoeba butschlii, Chilomastix mesnili, Balantidium coli and Blastocystis cells) and trophozoites from Troglodytella abrassarti and Balantidium coli. Eggs from different helminths (strongylids, Ascaris lumbricoides, Abbreviata caucasica, Trichuris sp., Capillaria sp., Enterobius anthropopeci, Bertiella sp., Hymenolepis diminuta and an undetermined fluke) were also observed. Finally, we observed eggs that could not be properly identified and classified. We did not observe any differences between the SIV+ and SIV- samples except for the unidentified eggs. The studied chimpanzees were highly parasitised by strongylid (85.1% of prevalence), Troglodytella (43.8%) and Blastocystis (2.9%), and the frequency of the other parasites ranged from 0.9 to 8.8%. These high levels of parasite infections could represent an additional burden in a population where there is a high rate of the SIV virus in circulation.

The Occurrence of Some Nonblood Protozoan Parasites in Wild and Domestic Mammals in South Africa.

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Lukášová, Radka; Halajian, Ali; Bártová, Eva; Kobédová, Kateřina; Swanepoel, Lourens H; O'Riain, M Justin

2018-04-01

Relatively little is known about protozoan parasites in African animals. Here we investigated the occurrence of protozoan parasites in mammals from South Africa. Oocysts of protozoan parasites were detected in 13 of 56 (23%) fecal samples using conventional microscopic examination methods. Cryptosporidium spp. and Cystoisospora spp. were detected in eight (14%) and five (9%) samples, respectively. Mixed parasitic infection of Cryptosporidium spp. and Cystoisospora spp. was recorded in banded mongoose ( Mungos mungo). Cryptosporidium spp. was detected for the first time in cheetah ( Acinonyx jubatus), spotted hyena ( Crocuta crocuta), and African polecat ( Ictonyx striatus). Antibodies to Toxoplasma gondii and Neospora caninum were not detected by enzyme-linked immunosorbent assay in any of 32 sera tested. We detected T. gondii by PCR in tissues of five of 243 (2%) animals: domestic dog ( Canis lupus familiaris), gerbil ( Gerbilliscus spp.), greater kudu ( Tragelaphus strepsiceros), honey badger ( Mellivora capensis), and white-tailed mongoose ( Ichneumia albicauda). Our isolation of T. gondii from white-tailed mongoose and honey badger was a unique finding. All tissue samples were negative for N. caninum. The study increases our knowledge on the occurrence of protozoan parasites in populations of wild and domestic animals in South Africa.

Protozoan and helminth parasite fauna of free-living Croatian wild wolves (Canis lupus) analyzed by scat collection.

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Hermosilla, Carlos; Kleinertz, Sonja; Silva, Liliana M R; Hirzmann, Jörg; Huber, Djuro; Kusak, Josip; Taubert, Anja

2017-01-15

The European wolf (Canis lupus) is a large carnivore species present in limited areas of Europe with several small populations still being considered as endangered. Wolves can be infected by a wide range of protozoan and metazoan parasites with some of them affecting free-living wolf health condition. On this account, an epidemiological survey was conducted to analyze the actual parasite fauna in Croatian wild wolves. In total, 400 individual faecal samples were collected during field studies on wolf ecology in the years 2002-2011. Parasite stages were identified by the sodium acetate acetic acid formalin (SAF)-technique, carbolfuchsin-stained faecal smears and Giardia/Cryptosporidium coproantigen-ELISAs. A subset of taeniid eggs-positive wolf samples was additionally analyzed by PCR and subsequent sequencing to identify eggs on Echinococcus granulosus/E. multilocularis species level. In total 18 taxa of parasites were here detected. Sarcocystis spp. (19.1%) occurred most frequently in faecal samples, being followed by Capillaria spp. (16%), ancylostomatids (13.1%), Crenosoma vulpis (4.6%), Angiostrongylus vasorum (3.1%), Toxocara canis (2.8%), Hammondia/Neospora spp. (2.6 %), Cystoisospora ohioensis (2.1%), Giardia spp. (2.1%), Cystoisospora canis (1.8%), Cryptosporidium spp. (1.8%), Trichuris vulpis (1.5%), Taenia spp. (1.5%), Diphyllobothrium latum (1.5%), Strongyloides spp. (0.5%), Opisthorchis felineus (0.5%), Toxascaris leonina (0.3%), Mesocestoides litteratus (0.3%) and Alaria alata (0.3%). Some of the here identified parasites represent relevant pathogens for wolves, circulating between these carnivorous definitive hosts and a variety of mammalian intermediate hosts, e. g. Taenia spp. and Sarcocystis spp., while others are considered exclusively pathogenic for canids (e.g. A. vasorum, C. vulpis, T. vulpis, Cystoisospora spp.). This study provides first records on the occurrence of the two relevant anthropozoonotic parasites, Giardia spp. and Cryptosporidium

Anthelmintic effect of Psidium guajava and Tagetes erecta on wild-type and Levamisole-resistant Caenorhabditis elegans strains.

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Piña-Vázquez, Denia M; Mayoral-Peña, Zyanya; Gómez-Sánchez, Maricela; Salazar-Olivo, Luis A; Arellano-Carbajal, Fausto

2017-04-18

Psidium guajava and Tagetes erecta have been used traditionally to treat gastrointestinal parasites, but their active metabolites and mechanisms of action remain largely unknown. To evaluate the anthelmintic potential of Psidium guajava and Tagetes erecta extracts on Levamisole-sensitive and Levamisole-resistant strains of the model nematode Caenorhabditis elegans. Aqueous extracts of Psidium guajava (PGE) and Tagetes erecta (TEE) were assayed on locomotion and egg-laying behaviors of the wild-type (N2) and Levamisole-resistant (CB193) strains of Caenorhabditis elegans. Both extracts paralyzed wild-type and Levamisole-resistant nematodes in a dose-dependent manner. In wild-type worms, TEE 25mg/mL induced a 75% paralysis after 8h of treatment and PGE 25mg/mL induced a 100% paralysis after 4h of treatment. PGE exerted a similar paralyzing effect on N2 wild-type and CB193 Levamisole-resistant worms, while TEE only partially paralyzed CB193 worms. TEE 25mg/mL decreased N2 egg-laying by 65% with respect to the untreated control, while PGE did it by 40%. Psidium guajava leaves and Tagetes erecta flower-heads possess hydrosoluble compounds that block the motility of Caenorhabditis elegans by a mechanism different to that of the anthelmintic drug Levamisole. Effects are also observable on oviposition, which was diminished in the wild-type worms. The strong anthelmintic effects in crude extracts of these plants warrants future work to identify their active compounds and to elucidate their molecular mechanisms of action. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Diseases and parasites of laboratory reared and wild population of banded pearl spot Etroplus suratensis (Cichlidae) in Goa

Digital Repository Service at National Institute of Oceanography (India)

Rattan, P.; Parulekar, A.H.

Banded Pearl spot Etroplus suratensis, the inhabitant of coastal backwaters and lagoons is one among the few finfish species identified for brackishwater farming. Common diseases and parasites from the wild population of Goa and from the laboratory...

Occurrence of gastrointestinal parasites in wild animals in State of Paraná, Brazil

Directory of Open Access Journals (Sweden)

LEW K. SPRENGER

2018-01-01

Full Text Available ABSTRACT The objective of this study was to determine the prevalence and diversity of gastrointestinal parasites in fecal samples from wild birds and mammals from the State of Paraná. In total, 220 stool samples were sent to Parasitic Diseases Laboratory of the Federal University of Paraná during 13 months (Jan/2013-Jan/2014. A total of 52.7% (116/220 of the animals were positive for cysts, oocysts, eggs and/or trophozoites. In birds, the positivity rate was 37.9% (25/66 and mammals was 59.1% (91/154. Strongyloidea superfamily eggs were observed in 37.3% (82/220 of the samples, Eimeria spp. in 10% (22/220, and Trichuris spp. in 4.5% (10/220. The most frequent mammal species were llamas (Lama glama, and dromedaries (Camelus bactrianus with infection rate of 70.1% (54/77 and 60.8% (14/23, respectively. In other hand, cockatiels (Nymphicus hollandicus and ring necks (Psittacula krameri, were the most researched birds, with infection rate of 20% (40/50 and 100% (6/6, respectively. A high prevalence of gastrointestinal parasites was observed in most of wildlife animals. Further investigations should be conducted focusing on parasite control strategies and the conservation measurements for harmonizing the human-animal interaction on the long-term, reducing associated health risks.

Toxoplasmosis in wild and domestic animals

Science.gov (United States)

Toxoplasma gondii is widely distributed in wild and domestic animals. The present chapter reviews toxoplasmosis in wild and domestic animals. Coverage in wild animal species is limited to confirmed cases of toxoplasmosis, cases with parasite isolation, cases with parasite detection by PCR, and exper...

Hematozoan parasites of Rio Grande wild turkeys from southern Texas (USA)

Science.gov (United States)

Castle, Marc D.; Christensen, Beth A.; Rocke, Tonie E.

1988-01-01

One hundred twenty-three of 300 blood samples (41%) taken from Rio Grande wild turkeys (Meleagris gallopavo intermedia) from three locations in southern Texas (Welder Wildlife Refuge, Chaparrosa Ranch, and Campo Alegre Ranch) and subinoculated into domestic broad-breasted white turkey poults were positive for a Plasmodium (Novyella) sp. Analysis of blood films from 350 turkeys revealed Haemoproteus meleagridis in 76% of the birds. A significantly greater mean parasite intensity was observed in birds from Welder Wildlife Refuge. Birds from the Campo Alegre Ranch exhibited a significantly higher prevalence of H. meleagridis than birds from Chaparrosa. The Plasmodium sp. was infective for canaries (Serinus canaria), bobwhites (Colinus virginianus), and ring-necked pheasants (Phasianus colchicus), but would not produce infection in white leghorn chickens (Gallus gallus) or Coturnix quail (Coturnix coturnix). Attempts to infect Culex tarsalis and C. pipiens pipiens were unsuccessful. Asexual erythrocytic synchrony was not observed when blood-induced infections were monitored in two domestic turkey poults every 4 hr for 72 hr. Exoerythrocytic stages were not found upon examination of impression smears and tissue samples taken from brain, liver, spleen, kidney, lung, and bone marrow. The Plasmodium sp. is most similar morphologically to three species in the subgenus Novyella, P. hexamerium, P. vaughani, and P. kempi. The most striking similarities are to P. hexamerium, and involve mean merozoite number, erythrocytic schizont location, and vertebrate host susceptibility. It differs from P. vaughani in being able to infect turkeys and in type of parasitized erythrocytes. Differences to P. kempi include mean merozoite number, and ability to infect pheasants, and its inability to develop inC. pipiens and C. tarsalis.

Wild carnivores (Mammalia) as hosts for ticks (Ixodida) in Panama

NARCIS (Netherlands)

Bermudez, S.E.; Esser, H.J.; Miranda, R.; Moreno, R.S.

2015-01-01

This study reports ticks collected from wild carnivores from different habitat types in Panama. We examined 94 individual wild carnivores and we found 87 parasitized by ticks: seven coyotes, six crab-eating foxes, 54 coatis, four raccoons, five ocelots, two pumas, two gray foxes, two skunks, and one

Molecular identification of parasitic nematodes (Nematoda: Strongylida) in feces of wild ruminants from Tunisia.

Science.gov (United States)

Said, Yousra; Gharbi, Mohamed; Mhadhbi, Moez; Dhibi, Moktar; Lahmar, Samia

2017-11-08

In Tunisia and other North African countries, there is a lack of knowledge about parasite biodiversity within threatened wild ruminants and there are not any studies on their gastrointestinal nematodes. Thus the aim of this study was to identify gastrointestinal fauna in the faecal samples of Tunisian wild ruminants. A total of 262 faecal samples were collected from domestic sheep and goat, and wild ruminants (Addax, Barbary sheep, Barbary red deer, Dorcas gazelle, Slender-horned gazelle and Scimitar-horned Oryx) living in protected areas. Samples were examined with floatation (saturated sodium chloride solution), polymerase chain reaction and sequencing of the second internal transcribed spacer region of the rDNA. Microscopic analysis allowed the identification of only Nematodirus genus or molecular tools allowed a first identification of five gastrointestinal nematode species in North African wild ruminants: Chabertia ovina (1.6%), Camelostrongylus mentulatus (1.6%), Marshallagia marshalli (4.7%), Nematodirus helvetianus (62.5%) and Nematodirus spathiger (29.7%). This study reported the first records of C. mentulatus and M. marshalli in Addax and of M. marshalli in Dorcas gazelle and it was the first reported record of N. helvetianus and M. marshalli in Tunisia.

Study of the Metatranscriptome of Eight Social and Solitary Wild Bee Species Reveals Novel Viruses and Bee Parasites.

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Schoonvaere, Karel; Smagghe, Guy; Francis, Frédéric; de Graaf, Dirk C

2018-01-01

Bees are associated with a remarkable diversity of microorganisms, including unicellular parasites, bacteria, fungi, and viruses. The application of next-generation sequencing approaches enables the identification of this rich species composition as well as the discovery of previously unknown associations. Using high-throughput polyadenylated ribonucleic acid (RNA) sequencing, we investigated the metatranscriptome of eight wild bee species ( Andrena cineraria, Andrena fulva, Andrena haemorrhoa, Bombus terrestris, Bombus cryptarum, Bombus pascuorum, Osmia bicornis , and Osmia cornuta ) sampled from four different localities in Belgium. Across the RNA sequencing libraries, 88-99% of the taxonomically informative reads were of the host transcriptome. Four viruses with homology to insect pathogens were found including two RNA viruses (belonging to the families Iflaviridae and Tymoviridae that harbor already viruses of honey bees), a double stranded DNA virus (family Nudiviridae ) and a single stranded DNA virus (family Parvoviridae ). In addition, we found genomic sequences of 11 unclassified arthropod viruses (related to negeviruses, sobemoviruses, totiviruses, rhabdoviruses, and mononegaviruses), seven plant pathogenic viruses, and one fungal virus. Interestingly, nege-like viruses appear to be widespread, host-specific, and capable of attaining high copy numbers inside bees. Next to viruses, three novel parasite associations were discovered in wild bees, including Crithidia pragensis and a tubulinosematid and a neogregarine parasite. Yeasts of the genus Metschnikowia were identified in solitary bees. This study gives a glimpse of the microorganisms and viruses associated with social and solitary wild bees and demonstrates that their diversity exceeds by far the subset of species first discovered in honey bees.

Study of the Metatranscriptome of Eight Social and Solitary Wild Bee Species Reveals Novel Viruses and Bee Parasites

Directory of Open Access Journals (Sweden)

Karel Schoonvaere

2018-02-01

Full Text Available Bees are associated with a remarkable diversity of microorganisms, including unicellular parasites, bacteria, fungi, and viruses. The application of next-generation sequencing approaches enables the identification of this rich species composition as well as the discovery of previously unknown associations. Using high-throughput polyadenylated ribonucleic acid (RNA sequencing, we investigated the metatranscriptome of eight wild bee species (Andrena cineraria, Andrena fulva, Andrena haemorrhoa, Bombus terrestris, Bombus cryptarum, Bombus pascuorum, Osmia bicornis, and Osmia cornuta sampled from four different localities in Belgium. Across the RNA sequencing libraries, 88–99% of the taxonomically informative reads were of the host transcriptome. Four viruses with homology to insect pathogens were found including two RNA viruses (belonging to the families Iflaviridae and Tymoviridae that harbor already viruses of honey bees, a double stranded DNA virus (family Nudiviridae and a single stranded DNA virus (family Parvoviridae. In addition, we found genomic sequences of 11 unclassified arthropod viruses (related to negeviruses, sobemoviruses, totiviruses, rhabdoviruses, and mononegaviruses, seven plant pathogenic viruses, and one fungal virus. Interestingly, nege-like viruses appear to be widespread, host-specific, and capable of attaining high copy numbers inside bees. Next to viruses, three novel parasite associations were discovered in wild bees, including Crithidia pragensis and a tubulinosematid and a neogregarine parasite. Yeasts of the genus Metschnikowia were identified in solitary bees. This study gives a glimpse of the microorganisms and viruses associated with social and solitary wild bees and demonstrates that their diversity exceeds by far the subset of species first discovered in honey bees.

Incidence of gastrointestinal parasitism of captive wild pigeons at Nagpur

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A. T. Borghare

Full Text Available Present study was planned to investigate the helminthic infection in captive wild pigeons (Columba livia at Maharajbagh Zoo Nagpur. All the 30 samples examined were found positive either with single or mixed helminthic infections. The result showed that the incidence of Capillaria sp, Ascaridia sp and  Hetarakis sp. were 56.66%, 76.66%, 16.66% respectively. Mixed parasitic infection was recorded in around 17 samples with either Ascaridia sp. and Capillaria sp or with Ascaridia sp. and Heterakis sp. One of 30 samples examined were found with the cysts of Balantidium coli. [Vet World 2009; 2(9.000: 343-

Babesia spp. in European wild ruminant species: parasite diversity and risk factors for infection

OpenAIRE

Michel , Adam O; Mathis , Alexander; Ryser-Degiorgis , Marie-Pierre

2014-01-01

International audience; Babesia are tick-borne parasites that are increasingly considered as a threat to animal and public health. We aimed to assess the role of European free-ranging wild ruminants as maintenance mammalian hosts for Babesia species and to determine risk factors for infection. EDTA blood was collected from 222 roe deer (Capreolus c. capreolus), 231 red deer (Cervus e. elaphus), 267 Alpine chamois (Rupicapra r. rupicapra) and 264 Alpine ibex (Capra i. ibex) from all over Switz...

Occurrence and distribution of Giardia species in wild rodents in Germany.

Science.gov (United States)

Helmy, Yosra A; Spierling, Nastasja G; Schmidt, Sabrina; Rosenfeld, Ulrike M; Reil, Daniela; Imholt, Christian; Jacob, Jens; Ulrich, Rainer G; Aebischer, Toni; Klotz, Christian

2018-03-27

Giardiasis is an important gastrointestinal parasitic disease in humans and other mammals caused by the protozoan Giardia duodenalis. This species complex is represented by genetically distinct groups (assemblages A-H) with varying zoonotic potential and host preferences. Wild rodents can harbor potentially zoonotic assemblages A and B, and the rodent-specific assemblage G. Other Giardia spp. found in these animals are Giardia muris and Giardia microti. For the latter, only limited information on genetic typing is available. It has been speculated that wild rodents might represent an important reservoir for parasites causing human giardiasis. The aim of this study was to investigate the occurrence and distribution of Giardia spp. and assemblage types in wild rodents from different study sites in Germany. Screening of 577 wild rodents of the genera Apodemus, Microtus and Myodes, sampled at eleven study sites in Germany, revealed a high overall Giardia prevalence. Giardia species determination at the SSU rDNA gene locus revealed that Apodemus mice, depending on species, were predominantly infected with one of two distinct G. muris sequence types. Giardia microti was the predominant parasite species found in voles of the genera Microtus and Myodes. Only a few animals were positive for potentially zoonotic G. duodenalis. Subtyping at the beta-giardin (bg) and glutamine dehydrogenase (gdh) genes strongly supported the existence of different phylogenetic subgroups of G. microti that are preferentially harbored by distinct host species. The present study highlights the preference of G. muris for Apodemus, and G. microti for Microtus and Myodes hosts and argues for a very low prevalence of zoonotic G. duodenalis assemblages in wild rodents in Germany. It also provides evidence that G. muris and G. microti subdivide into several phylogenetically distinguishable subgroups, each of which appears to be preferentially harbored by species of a particular rodent host genus

Monkeys in the middle: parasite transmission through the social network of a wild primate.

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Andrew J J MacIntosh

Full Text Available In wildlife populations, group-living is thought to increase the probability of parasite transmission because contact rates increase at high host densities. Physical contact, such as social grooming, is an important component of group structure, but it can also increase the risk of exposure to infection for individuals because it provides a mechanism for transmission of potentially pathogenic organisms. Living in groups can also create variation in susceptibility to infection among individuals because circulating levels of immunosuppressive hormones like glucocorticoids often depend on an individual's position within the group's social structure. Yet, little is known about the relative roles of socially mediated exposure versus susceptibility in parasite transmission among free-living animal groups. To address this issue, we investigate the relationship between host dominance hierarchy and nematode parasite transmission among females in a wild group of Japanese macaques (Macaca fuscata yakui. We use social network analysis to describe each individual female's position within the grooming network in relation to dominance rank and relative levels of infection. Our results suggest that the number of directly-transmitted parasite species infecting each female, and the relative amount of transmission stages that one of these species sheds in faeces, both increase with dominance rank. Female centrality within the network, which shows positive associations with dominance hierarchy, is also positively associated with infection by certain parasite species, suggesting that the measured rank-bias in transmission may reflect variation in exposure rather than susceptibility. This is supported by the lack of a clear relationship between rank and faecal cortisol, as an indicator of stress, in a subset of these females. Thus, socially mediated exposure appears to be important for direct transmission of nematode parasites, lending support to the idea that a

Monkeys in the Middle: Parasite Transmission through the Social Network of a Wild Primate

Science.gov (United States)

MacIntosh, Andrew J. J.; Jacobs, Armand; Garcia, Cécile; Shimizu, Keiko; Mouri, Keiko; Huffman, Michael A.; Hernandez, Alexander D.

2012-01-01

In wildlife populations, group-living is thought to increase the probability of parasite transmission because contact rates increase at high host densities. Physical contact, such as social grooming, is an important component of group structure, but it can also increase the risk of exposure to infection for individuals because it provides a mechanism for transmission of potentially pathogenic organisms. Living in groups can also create variation in susceptibility to infection among individuals because circulating levels of immunosuppressive hormones like glucocorticoids often depend on an individual’s position within the group’s social structure. Yet, little is known about the relative roles of socially mediated exposure versus susceptibility in parasite transmission among free-living animal groups. To address this issue, we investigate the relationship between host dominance hierarchy and nematode parasite transmission among females in a wild group of Japanese macaques (Macaca fuscata yakui). We use social network analysis to describe each individual female’s position within the grooming network in relation to dominance rank and relative levels of infection. Our results suggest that the number of directly-transmitted parasite species infecting each female, and the relative amount of transmission stages that one of these species sheds in faeces, both increase with dominance rank. Female centrality within the network, which shows positive associations with dominance hierarchy, is also positively associated with infection by certain parasite species, suggesting that the measured rank-bias in transmission may reflect variation in exposure rather than susceptibility. This is supported by the lack of a clear relationship between rank and faecal cortisol, as an indicator of stress, in a subset of these females. Thus, socially mediated exposure appears to be important for direct transmission of nematode parasites, lending support to the idea that a classical fitness

Co-Infection and Wild Animal Health: Effects of Trypanosomatids and Gastrointestinal Parasites on Coatis of the Brazilian Pantanal.

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Natalie Olifiers

Full Text Available Wild animals are infected by diverse parasites, but how they influence host health is poorly understood. We examined the relationship of trypanosomatids and gastrointestinal parasites with health of wild brown-nosed coatis (Nasua nasua from the Brazilian Pantanal. We used coati body condition and hematological parameters as response variables in linear models that were compared using an information theoretic approach. Predictors were high/low parasitemias by Trypanosoma cruzi and T. evansi, and indices representing the abundance of distinct groups of gastrointestinal parasites. We also analyzed how host health changed with host sex and reproductive seasonality. Hemoparasites was best related to coati body condition and hematological indices, whereas abundance of gastrointestinal parasites was relatively less associated with coati health. Additionally, some associations were best predicted by models that incorporated reproductive seasonality and host sex. Overall, we observed a lower health condition during the breeding season, when coatis are under reproductive stress and may be less able to handle infection. In addition, females seem to handle infection better than males. Body condition was lower in coatis with high parasitemias of T. evansi, especially during the reproductive season. Total red blood cell counts, packed cell volume, platelets and eosinophils were also lower in animals with high T. evansi parasitemias. Total white blood cell counts and mature neutrophils were lower in animals with high parasitemias for both Trypanosoma species, with neutrophils decreasing mainly during the reproductive season. Overall, decreases in hematological parameters of females with T. evansi high parasitemias were less evident. For T. cruzi, monocytes decreased in individuals with high parasitemias. High abundances of microfilariae in the bloodstream, and cestode eggs and coccidian oocysts in feces were also associated with coati blood parameters. This

Co-Infection and Wild Animal Health: Effects of Trypanosomatids and Gastrointestinal Parasites on Coatis of the Brazilian Pantanal.

Science.gov (United States)

Olifiers, Natalie; Jansen, Ana Maria; Herrera, Heitor Miraglia; Bianchi, Rita de Cassia; D'Andrea, Paulo Sergio; Mourão, Guilherme de Miranda; Gompper, Matthew Edzart

2015-01-01

Wild animals are infected by diverse parasites, but how they influence host health is poorly understood. We examined the relationship of trypanosomatids and gastrointestinal parasites with health of wild brown-nosed coatis (Nasua nasua) from the Brazilian Pantanal. We used coati body condition and hematological parameters as response variables in linear models that were compared using an information theoretic approach. Predictors were high/low parasitemias by Trypanosoma cruzi and T. evansi, and indices representing the abundance of distinct groups of gastrointestinal parasites. We also analyzed how host health changed with host sex and reproductive seasonality. Hemoparasites was best related to coati body condition and hematological indices, whereas abundance of gastrointestinal parasites was relatively less associated with coati health. Additionally, some associations were best predicted by models that incorporated reproductive seasonality and host sex. Overall, we observed a lower health condition during the breeding season, when coatis are under reproductive stress and may be less able to handle infection. In addition, females seem to handle infection better than males. Body condition was lower in coatis with high parasitemias of T. evansi, especially during the reproductive season. Total red blood cell counts, packed cell volume, platelets and eosinophils were also lower in animals with high T. evansi parasitemias. Total white blood cell counts and mature neutrophils were lower in animals with high parasitemias for both Trypanosoma species, with neutrophils decreasing mainly during the reproductive season. Overall, decreases in hematological parameters of females with T. evansi high parasitemias were less evident. For T. cruzi, monocytes decreased in individuals with high parasitemias. High abundances of microfilariae in the bloodstream, and cestode eggs and coccidian oocysts in feces were also associated with coati blood parameters. This study shows the

Seasonal egg output of gastro-intestinal parasites in wild ungulates in a mediterranean area (central Italy

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Marta Magi

2006-03-01

Full Text Available Abstract Seasonal egg (or oocyst output of gastro-intestinal parasites of wild ungulates was studied in a Mediterranean protected area, the Monti Livornesi Park (Livorno, Tuscany region, Central Italy. Samples of faeces of wild boars (Sus scrofa and mouflons (Ovis ammon were collected monthly for one year. The observed trends of egg output were analysed taking into account seasonal variations of temperature and rainfall, life-cycle and survival strategy of parasites, and health condition of hosts. In our Mediterranean study area, the peaks of egg output appear in different months according to different biology and survival strategies of parasites. Riassunto Emissione stagionale di uova di parassiti gastrointestinali in cinghiali (Sus scrofa e in mufloni (Ovis ammon di un’area mediterranea (Italia centrale. E' stata studiata l'emissione stagionale di uova (o oocisti di parassiti nelle feci di ungulati selvatici in una zona mediterranea protetta, il Parco dei Monti Livornesi (Livorno, Toscana, Italia Centrale. Per un anno sono stati raccolti mensilmente campioni di feci di Cinghiale (Sus scrofa e di Muflone (Ovis ammon. Gli andamenti osservati di emissione di uova sono stati analizzati tenendo conto delle variazioni di temperatura e piovosità stagionali, del ciclo biologico e della strategia di sopravvivenza dei parassiti, e delle condizioni sanitarie dell'ospite. E’ risultato che in una zona mediterranea come quella considerata i picchi di emissione di uova appaiono in mesi differenti in relazione alla biologia e alle strategie di sopravvivenza dei diversi parassiti.

Expression of cancer-associated simple mucin-type O-glycosylated antigens in parasites.

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Osinaga, Eduardo

2007-01-01

Simple mucin-type O-glycan structures, such as Tn, TF, sialyl-Tn and Tk antigens, are among of the most specific human cancer-associated structures. These antigens are involved in several types of receptor-ligand interactions, and they are potential targets for immunotherapy. In the last few years several simple mucin-type O-glycan antigens were identified in different species belonging to the main two helminth parasite phyla, and sialyl-Tn bearing glycoproteins were detected in Trypanosoma cruzi. These results are of interest to understand new aspects in parasite glycoimmunology and may help identify new biological characteristics of parasites as well of the host-parasite relationship. Considering that different groups reported a negative correlation between certain parasite infections and cancer development, we could hypothesize that simple mucin-type O-glycosylated antigens obtained from parasites could be good potential targets for cancer immunotherapy.

Survey of wild mammal hosts of cutaneous leishmaniasis parasites in panamá and costa rica.

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González, Kadir; Calzada, José E; Saldaña, Azael; Rigg, Chystrie A; Alvarado, Gilbert; Rodríguez-Herrera, Bernal; Kitron, Uriel D; Adler, Gregory H; Gottdenker, Nicole L; Chaves, Luis Fernando; Baldi, Mario

2015-03-01

The eco-epidemiology of American cutaneous leishmaniasis (ACL) is driven by animal reservoir species that are a source of infection for sand flies that serve as vectors infecting humans with Leishmania spp parasites. The emergence and re-emergence of this disease across Latin America calls for further studies to identify reservoir species associated with enzootic transmission. Here, we present results from a survey of 52 individuals from 13 wild mammal species at endemic sites in Costa Rica and Panama where ACL mammal hosts have not been previously studied. For Leishmania spp. diagnostics we employed a novel PCR technique using blood samples collected on filter paper. We only found Leishmania spp parasites in one host, the two-toed sloth, Choloepus hoffmanni. Our findings add further support to the role of two-toed sloths as an important ACL reservoir in Central America.

Effect of Habitat Type on Parasitism of Ectatomma ruidum by Eucharitid Wasps

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Aymer Andrés Vásquez-Ordóñez

2012-01-01

Full Text Available Eucharitidae are parasitoids that use immature stages of ants for their development. Kapala Cameron is the genus most frequently collected in the Neotropics, but little is known about the biology and behavior of any of the species of this genus. We aimed to evaluate the effect of habitat type on eucharitid parasitism and to contribute to the knowledge of the host-parasite relationship between Kapala sp. and the poneromorph ant Ectatomma ruidum (Roger in Colombia. Twenty E. ruidum colonies were extracted from two different habitat types (woodland and grassland, and larvae and cocoons (pupae were examined in search for parasitoids in different stages of development. Globally, 60% of the colonies were parasitized, with 1.3% of larvae and 4% of pupae parasitized. Planidia (first-instar larvae, pupae, and adults of the parasitoid were observed. All of the pupae and adult parasitoids belonged to Kapala iridicolor Cameron. All the colonies collected in the woodlands were parasitized and contained more parasitized larvae (2% and parasitized cocoons (8% than those collected in grasslands (4/12 parasitized colonies, 0.5% parasitized larvae, 0.8% parasitized cocoons. The relationship observed between habitat type and parasitism prevalence is a novel aspect of the study of eucharitid impact on ant host populations.

First record of intestinal parasites in a wild population of jaguar in the Brazilian Atlantic Forest

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Ana Carolina Srbek-Araujo

Full Text Available Small and isolated wildlife populations may be more susceptible to disease, which makes illness an important issue to investigate regarding the conservation of large carnivores. Here, we present the results of the first investigation of intestinal parasites in one of the last remaining populations of jaguars in the Brazilian Atlantic Forest. We studied parasites from fecal samples using three different techniques for parasitological examination: floatation in saturated sodium chloride solution, sedimentation and formalin-ether centrifugation. Intestinal parasites were detected in 70% of the analyzed samples, and seven taxa (mean = 3.7 taxa/sample were identified. All the groups of parasites that were identified have been recorded in previous jaguar studies. However, the records of Class Trematoda and nematodes Trichuridae are the first evidence of these groups of worms in free-ranging jaguars in Brazil. Although our results do not provide conclusive evidence on the health of this jaguar population, given its very small size (approximately 20 animals we stress the need to properly understand the dynamics of disease in this wild population and to evaluate the risk of contracting new diseases from domestic species inhabiting the neighboring areas. These represent imperative actions for the successful conservation of this threatened population of jaguar.

Glucosinolates from Host Plants Influence Growth of the Parasitic Plant Cuscuta gronovii and Its Susceptibility to Aphid Feeding.

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Smith, Jason D; Woldemariam, Melkamu G; Mescher, Mark C; Jander, Georg; De Moraes, Consuelo M

2016-09-01

Parasitic plants acquire diverse secondary metabolites from their hosts, including defense compounds that target insect herbivores. However, the ecological implications of this phenomenon, including the potential enhancement of parasite defenses, remain largely unexplored. We studied the translocation of glucosinolates from the brassicaceous host plant Arabidopsis (Arabidopsis thaliana) into parasitic dodder vines (Convolvulaceae; Cuscuta gronovii) and its effects on the parasite itself and on dodder-aphid interactions. Aliphatic and indole glucosinolates reached concentrations in parasite tissues higher than those observed in corresponding host tissues. Dodder growth was enhanced on cyp79B2 cyp79B3 hosts (without indole glucosinolates) but inhibited on atr1D hosts (with elevated indole glucosinolates) relative to wild-type hosts, which responded to parasitism with localized elevation of indole and aliphatic glucosinolates. These findings implicate indole glucosinolates in defense against parasitic plants. Rates of settling and survival on dodder vines by pea aphids (Acyrthosiphon pisum) were reduced significantly when dodder parasitized glucosinolate-producing hosts (wild type and atr1D) compared with glucosinolate-free hosts (cyp79B2 cyp79B3 myb28 myb29). However, settling and survival of green peach aphids (Myzus persicae) were not affected. M. persicae population growth was actually reduced on dodder parasitizing glucosinolate-free hosts compared with wild-type or atr1D hosts, even though stems of the former contain less glucosinolates and more amino acids. Strikingly, this effect was reversed when the aphids fed directly upon Arabidopsis, which indicates an interactive effect of parasite and host genotype on M. persicae that stems from host effects on dodder. Thus, our findings indicate that glucosinolates may have both direct and indirect effects on dodder-feeding herbivores. © 2016 American Society of Plant Biologists. All rights reserved.

Intestinal Parasites and Anthelmintic Treatments in a Laboratory Colony of Wild-caught African Pouched Rats (Cricetomys ansorgei)

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Cullin, Cassandra O; Sellers, Matthew S; Rogers, Erin R; Scott, Kathleen E; Lee, Danielle N; Ophir, Alexander G; Jackson, Todd A

2017-01-01

African giant pouched rats (Cricetomys spp.) are large rodents native to subSaharan Africa. Wild-caught pouched rats identified as Cricetomys ansorgei (n = 49) were imported from Tanzania. A survey of gastrointestinal parasitism by fecal flotation revealed the presence of multiple parasites, including Nippostrongylus spp., Heterakis spp., Trichuris spp., Hymenolepis spp., Raillietina spp., and Eimeria spp. Oral self-administered fenbendazole (150 ppm), topical moxidectin (2 mg/kg), pyrantel pamoate (15 mg/kg), piperazine (100 mg/kg daily), and injectable ivermectin (0.25 mg/kg) were used to determine effective treatment options for the gastrointestinal parasites present in the colony. Pyrantel pamoate in a treat vehicle and piperazine in water bottles were easily administered and significantly reduced the numbers of animals shedding Nippostrongylus spp. and Heterakis spp. during the study. Moxidectin and ivermectin were clinically ineffective at reducing fecal egg shedding. Fenbendazole was most effective at clearing infection with Trichuris spp. Although 10 mg/kg praziquantel was ineffective, a single dose of 30 mg/kg praziquantel significantly reduced the number of African pouched rats that shed cestode embryos. A combination treatment may be necessary to successfully treat all parasites present in any given animal. PMID:28935004

Environmental risk and toxicology of human and veterinary waste pharmaceutical exposure to wild aquatic host-parasite relationships.

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Morley, Neil J

2009-03-01

Pollution of the aquatic environment by human and veterinary waste pharmaceuticals is an increasing area of concern but little is known about their ecotoxicological effects on wildlife. In particular the interactions between pharmaceuticals and natural stressors of aquatic communities remains to be elucidated. A common natural stressor of freshwater and marine organisms are protozoan and metazoan parasites, which can have significant effects on host physiology and population structure, especially under the influence of many traditional kinds of toxic pollutants. However, little is known about the effects of waste pharmaceuticals to host-parasite dynamics. In order to assess the risk waste pharmaceuticals pose to aquatic wildlife it has been suggested the use of toxicological data derived from mammals during the product development of pharmaceuticals may be useful for predicting toxic effects. An additional similar source of information is the extensive clinical studies undertaken with numerous classes of drugs against parasites of human and veterinary importance. These studies may form the basis of preliminary risk assessments to aquatic populations and their interactions with parasitic diseases in pharmaceutical-exposed habitats. The present article reviews the effects of the most common classes of pharmaceutical medicines to host-parasite relationships and assesses the risk they may pose to wild aquatic organisms. In addition the effects of pharmaceutical mixtures, the importance of sewage treatment, and the risk of developing resistant strains of parasites are also assessed. Copyright © 2008 Elsevier B.V. All rights reserved.

Does the parasite-mediated selection drive the MHC class IIB diversity in wild populations of European chub (Squalius cephalus)?

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Seifertová, Mária; Jarkovský, Jiří; Šimková, Andrea

2016-04-01

The genes of major histocompatibility complex (MHC) provide an excellent opportunity to study host-parasite relationships because they are expected to evolve in response to parasites and variation in parasite communities. In this study, we investigated the potential role of parasite-mediated selection acting on MHC class IIB (DAB) genes in European chub (Squalius cephalus) natural populations. We found significant differences between populations in metazoan parasites, neutral and adaptive genetic diversities. The analyses based on pairwise data revealed that populations with dissimilar MHC allelic profiles were geographically distant populations with significantly different diversity in microsatellites and a dissimilar composition of parasite communities. The results from the generalized estimating equations method (GEE) on the level of individuals revealed that metazoan parasite load in European chub was influenced by the diversity of DAB alleles as well as by the diversity of neutral genetic markers and host traits reflecting condition and immunocompetence. The multivariate co-inertia analysis showed specific associations between DAB alleles and parasite species. DAB1-like alleles were more involved in associations with ectoparasites, while DAB3-like alleles were positively associated with endoparasites which could suggest potential differences between DAB genes caused by different selection pressure. Our study revealed that parasite-mediated selection is not the only variable affecting MHC diversity in European chub; however, we strongly support the role of neutral processes as the main driver of DAB diversity across populations. In addition, our study contributes to the understanding of the evolution of MHC genes in wild living fish.

Biogeography of Parasitic Nematode Communities in the Galápagos Giant Tortoise: Implications for Conservation Management.

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Guillaume Fournié

Full Text Available The Galápagos giant tortoise is an icon of the unique, endemic biodiversity of Galápagos, but little is known of its parasitic fauna. We assessed the diversity of parasitic nematode communities and their spatial distributions within four wild tortoise populations comprising three species across three Galápagos islands, and consider their implication for Galápagos tortoise conservation programmes. Coprological examinations revealed nematode eggs to be common, with more than 80% of tortoises infected within each wild population. Faecal samples from tortoises within captive breeding centres on Santa Cruz, Isabela and San Cristobal islands also were examined. Five different nematode egg types were identified: oxyuroid, ascarid, trichurid and two types of strongyle. Sequencing of the 18S small-subunit ribosomal RNA gene from adult nematodes passed with faeces identified novel sequences indicative of rhabditid and ascaridid species. In the wild, the composition of nematode communities varied according to tortoise species, which co-varied with island, but nematode diversity and abundance were reduced or altered in captive-reared animals. Evolutionary and ecological factors are likely responsible for the variation in nematode distributions in the wild. This possible species/island-parasite co-evolution has not been considered previously for Galápagos tortoises. We recommend that conservation efforts, such as the current Galápagos tortoise captive breeding/rearing and release programme, be managed with respect to parasite biogeography and host-parasite co-evolutionary processes in addition to the biogeography of the host.

Cessation of a salmon decline with control of parasites

KAUST Repository

Peacock, Stephanie J.

2013-04-01

The resilience of coastal social-ecological systems may depend on adaptive responses to aquaculture disease outbreaks that can threaten wild and farm fish. A nine-year study of parasitic sea lice (Lepeophtheirus salmonis) and pink salmon (Oncorhynchus gorbuscha) from Pacific Canada indicates that adaptive changes in parasite management on salmon farms have yielded positive conservation outcomes. After four years of sea lice epizootics and wild salmon population decline, parasiticide application on salmon farms was adapted to the timing of wild salmon migrations. Winter treatment of farm fish with parasiticides, prior to the out-migration of wild juvenile salmon, has reduced epizootics of wild salmon without significantly increasing the annual number of treatments. Levels of parasites on wild juvenile salmon significantly influence the growth rate of affected salmon populations, suggesting that these changes in management have had positive outcomes for wild salmon populations. These adaptive changes have not occurred through formal adaptive management, but rather, through multi-stakeholder processes arising from a contentious scientific and public debate. Despite the apparent success of parasite control on salmon farms in the study region, there remain concerns about the long-term sustainability of this approach because of the unknown ecological effects of parasticides and the potential for parasite resistance to chemical treatments. © 2013 by the Ecological Society of America.

Footprints of directional selection in wild Atlantic salmon populations: evidence for parasite-driven evolution?

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Zueva, Ksenia J; Lumme, Jaakko; Veselov, Alexey E; Kent, Matthew P; Lien, Sigbjørn; Primmer, Craig R

2014-01-01

Mechanisms of host-parasite co-adaptation have long been of interest in evolutionary biology; however, determining the genetic basis of parasite resistance has been challenging. Current advances in genome technologies provide new opportunities for obtaining a genome-scale view of the action of parasite-driven natural selection in wild populations and thus facilitate the search for specific genomic regions underlying inter-population differences in pathogen response. European populations of Atlantic salmon (Salmo salar L.) exhibit natural variance in susceptibility levels to the ectoparasite Gyrodactylus salaris Malmberg 1957, ranging from resistance to extreme susceptibility, and are therefore a good model for studying the evolution of virulence and resistance. However, distinguishing the molecular signatures of genetic drift and environment-associated selection in small populations such as land-locked Atlantic salmon populations presents a challenge, specifically in the search for pathogen-driven selection. We used a novel genome-scan analysis approach that enabled us to i) identify signals of selection in salmon populations affected by varying levels of genetic drift and ii) separate potentially selected loci into the categories of pathogen (G. salaris)-driven selection and selection acting upon other environmental characteristics. A total of 4631 single nucleotide polymorphisms (SNPs) were screened in Atlantic salmon from 12 different northern European populations. We identified three genomic regions potentially affected by parasite-driven selection, as well as three regions presumably affected by salinity-driven directional selection. Functional annotation of candidate SNPs is consistent with the role of the detected genomic regions in immune defence and, implicitly, in osmoregulation. These results provide new insights into the genetic basis of pathogen susceptibility in Atlantic salmon and will enable future searches for the specific genes involved.

Glucosinolates from Host Plants Influence Growth of the Parasitic Plant Cuscuta gronovii and Its Susceptibility to Aphid Feeding1[OPEN

Science.gov (United States)

2016-01-01

Parasitic plants acquire diverse secondary metabolites from their hosts, including defense compounds that target insect herbivores. However, the ecological implications of this phenomenon, including the potential enhancement of parasite defenses, remain largely unexplored. We studied the translocation of glucosinolates from the brassicaceous host plant Arabidopsis (Arabidopsis thaliana) into parasitic dodder vines (Convolvulaceae; Cuscuta gronovii) and its effects on the parasite itself and on dodder-aphid interactions. Aliphatic and indole glucosinolates reached concentrations in parasite tissues higher than those observed in corresponding host tissues. Dodder growth was enhanced on cyp79B2 cyp79B3 hosts (without indole glucosinolates) but inhibited on atr1D hosts (with elevated indole glucosinolates) relative to wild-type hosts, which responded to parasitism with localized elevation of indole and aliphatic glucosinolates. These findings implicate indole glucosinolates in defense against parasitic plants. Rates of settling and survival on dodder vines by pea aphids (Acyrthosiphon pisum) were reduced significantly when dodder parasitized glucosinolate-producing hosts (wild type and atr1D) compared with glucosinolate-free hosts (cyp79B2 cyp79B3 myb28 myb29). However, settling and survival of green peach aphids (Myzus persicae) were not affected. M. persicae population growth was actually reduced on dodder parasitizing glucosinolate-free hosts compared with wild-type or atr1D hosts, even though stems of the former contain less glucosinolates and more amino acids. Strikingly, this effect was reversed when the aphids fed directly upon Arabidopsis, which indicates an interactive effect of parasite and host genotype on M. persicae that stems from host effects on dodder. Thus, our findings indicate that glucosinolates may have both direct and indirect effects on dodder-feeding herbivores. PMID:27482077

Variation in faecal water content may confound estimates of gastro-intestinal parasite intensity in wild African herbivores.

Science.gov (United States)

Turner, W C; Cizauskas, C A; Getz, W M

2010-03-01

Estimates of parasite intensity within host populations are essential for many studies of host-parasite relationships. Here we evaluated the seasonal, age- and sex-related variability in faecal water content for two wild ungulate species, springbok (Antidorcas marsupialis) and plains zebra (Equus quagga). We then assessed whether or not faecal water content biased conclusions regarding differences in strongyle infection rates by season, age or sex. There was evidence of significant variation in faecal water content by season and age for both species, and by sex in springbok. Analyses of faecal egg counts demonstrated that sex was a near-significant factor in explaining variation in strongyle parasite infection rates in zebra (P = 0.055) and springbok (P = 0.052) using wet-weight faecal samples. However, once these intensity estimates were re-scaled by the percent of dry matter in the faeces, sex was no longer a significant factor (zebra, P = 0.268; springbok, P = 0.234). These results demonstrate that variation in faecal water content may confound analyses and could produce spurious conclusions, as was the case with host sex as a factor in the analysis. We thus recommend that researchers assess whether water variation could be a confounding factor when designing and performing research using faecal indices of parasite intensity.

Generalists at the interface: Nematode transmission between wild and domestic ungulates.

Science.gov (United States)

Walker, Josephine G; Morgan, Eric R

2014-12-01

Many parasitic nematode species are generalists capable of infecting multiple host species. The complex life cycle of nematodes, involving partial development outside of the host, facilitates transmission of these parasites between host species even when there is no direct contact between hosts. Infective nematode larvae persist in the environment, and where grazing or water sources are shared ingestion of parasite larvae deposited by different host species is likely. In this paper we examine the extent to which nematode parasite species have been observed in sympatric wild and domestic ungulates. First, using existing host-parasite databases, we describe expected overlap of 412 nematode species between 76 wild and 8 domestic ungulate host species. Our results indicate that host-specific parasites make up less than half of the nematode parasites infecting any particular ungulate host species. For wild host species, between 14% (for common warthog) and 76% (for mouflon) of parasitic nematode species are shared with domestic species. For domestic host species, between 42% (for horse) and 77% (for llamas/alpacas) of parasitic nematode species are shared with wild species. We also present an index of liability to describe the risk of cross-boundary parasites to each host species. We then examine specific examples from the literature in which transmission of nematode parasites between domestic and wild ungulates is described. However, there are many limitations in the existing data due to geographical bias and certain host species being studied more frequently than others. Although we demonstrate that many species of parasitic nematode are found in both wild and domestic hosts, little work has been done to demonstrate whether transmission is occurring between species or whether similar strains circulate separately. Additional research on cross-species transmission, including the use of models and of genetic methods to define strains, will provide evidence to answer this

Generalists at the interface: Nematode transmission between wild and domestic ungulates

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Josephine G. Walker

2014-12-01

Full Text Available Many parasitic nematode species are generalists capable of infecting multiple host species. The complex life cycle of nematodes, involving partial development outside of the host, facilitates transmission of these parasites between host species even when there is no direct contact between hosts. Infective nematode larvae persist in the environment, and where grazing or water sources are shared ingestion of parasite larvae deposited by different host species is likely. In this paper we examine the extent to which nematode parasite species have been observed in sympatric wild and domestic ungulates. First, using existing host–parasite databases, we describe expected overlap of 412 nematode species between 76 wild and 8 domestic ungulate host species. Our results indicate that host-specific parasites make up less than half of the nematode parasites infecting any particular ungulate host species. For wild host species, between 14% (for common warthog and 76% (for mouflon of parasitic nematode species are shared with domestic species. For domestic host species, between 42% (for horse and 77% (for llamas/alpacas of parasitic nematode species are shared with wild species. We also present an index of liability to describe the risk of cross-boundary parasites to each host species. We then examine specific examples from the literature in which transmission of nematode parasites between domestic and wild ungulates is described. However, there are many limitations in the existing data due to geographical bias and certain host species being studied more frequently than others. Although we demonstrate that many species of parasitic nematode are found in both wild and domestic hosts, little work has been done to demonstrate whether transmission is occurring between species or whether similar strains circulate separately. Additional research on cross-species transmission, including the use of models and of genetic methods to define strains, will provide

Blood parasites, total plasma protein and packed cell volume of small wild mammals trapped in three mountain ranges of the Atlantic Forest in Southeastern Brazil

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MAML. Silva

Full Text Available A study of blood parasites in small wild non-flying mammals was undertaken in three areas of the Atlantic Forest in Southeastern Brazil: Serra de Itatiaia, RJ, Serra da Bocaina, SP and Serra da Fartura, SP, from June 1999 to May 2001. A total of 450 animals (15 species were captured in traps and it was observed in 15.5% of the blood smears the presence of Haemobartonella sp. and Babesia sp. in red blood cells. There was no statistically significant difference between parasited and non-parasited specimens regarding total plasma protein, packed cell volume and body weight, which strongly suggests that these specimens might be parasite reservoirs.

Foodborne parasites from wildlife

DEFF Research Database (Denmark)

Kapel, Christian Moliin Outzen; Fredensborg, Brian Lund

2015-01-01

The majority of wild foods consumed by humans are sourced from intensively managed or semi-farmed populations. Management practices inevitably affect wildlife density and habitat characteristics, which are key elements in the transmission of parasites. We consider the risk of transmission...... of foodborne parasites to humans from wildlife maintained under natural or semi-natural conditions. A deeper understanding will be useful in counteracting foodborne parasites arising from the growing industry of novel and exotic foods....

Babesia spp. in European wild ruminant species: parasite diversity and risk factors for infection.

Science.gov (United States)

Michel, Adam O; Mathis, Alexander; Ryser-Degiorgis, Marie-Pierre

2014-06-13

Babesia are tick-borne parasites that are increasingly considered as a threat to animal and public health. We aimed to assess the role of European free-ranging wild ruminants as maintenance mammalian hosts for Babesia species and to determine risk factors for infection. EDTA blood was collected from 222 roe deer (Capreolus c. capreolus), 231 red deer (Cervus e. elaphus), 267 Alpine chamois (Rupicapra r. rupicapra) and 264 Alpine ibex (Capra i. ibex) from all over Switzerland and analysed by PCR with pan-Babesia primers targeting the 18S rRNA gene, primers specific for B. capreoli and Babesia sp. EU1, and by sequencing. Babesia species, including B. divergens, B. capreoli, Babesia sp. EU1, Babesia sp. CH1 and B. motasi, were detected in 10.7% of all samples. Five individuals were co-infected with two Babesia species. Infection with specific Babesia varied widely between host species. Cervidae were significantly more infected with Babesia spp. than Caprinae. Babesia capreoli and Babesia sp. EU1 were mostly found in roe deer (prevalences 17.1% and 7.7%, respectively) and B. divergens and Babesia sp. CH1 only in red deer. Factors significantly associated with infection were low altitude and young age. Identification of Babesia sp. CH1 in red deer, co-infection with multiple Babesia species and infection of wild Caprinae with B. motasi and Babesia sp. EU1 are novel findings. We propose wild Caprinae as spillover or accidental hosts for Babesia species but wild Cervidae as mammalian reservoir hosts for B. capreoli, possibly Babesia sp. EU1 and Babesia sp. CH1, whereas their role regarding B. divergens is more elusive.

Evaluation of MIC Strip Isavuconazole test for susceptibility testing of wild-type and non-wild-type Aspergillus fumigatus isolates

DEFF Research Database (Denmark)

Arendrup, Maiken Cavling; Verweij, Paul; Nielsen, Henrik Vedel

2017-01-01

We evaluated the MIC Strip Isavuconazole test against EUCAST E.Def 9.3 by using 40 wild-type and 39 CYP51A mutant Aspergillus fumigatus strains. The strip full inhibition endpoint (FIE) and 80% growth inhibition endpoint were determined by two independent readers, reader 1 (R1) and R2. The essent......We evaluated the MIC Strip Isavuconazole test against EUCAST E.Def 9.3 by using 40 wild-type and 39 CYP51A mutant Aspergillus fumigatus strains. The strip full inhibition endpoint (FIE) and 80% growth inhibition endpoint were determined by two independent readers, reader 1 (R1) and R2...

UV-sensitivity and repair of UV-damage in Salmonella of wild type

International Nuclear Information System (INIS)

Kondratiev, Y.S.; Brukhansky, G.V.; Andreeva, I.V.; Skavronskaya, A.G.

1977-01-01

The UV-sensitivity of wild type Salmonella strains has been compared to that of wild type E.coli and its UV-sensitive mutants. Many wild type Salmonella strains are 4-5 times more sensitive than wild type E.coli and their inactivation curve is similar to that for E.coli with a mutation in the polA gene. Alkaline sucrose gradient centrifugation has shown a deficiency of these strains in normal excision repair of UV-damaged DNA. This deficiency is not a Salmonella genus feature because one strain as resistant as wild type E.coli was found. This resistant strain showed normal excision repair in alkaline sucrose gradient centrifugation experiments. The possible influence of plasmids and mutations in repair genes on the ability of Salmonella to repair UV-damaged DNA is discussed. (orig.) [de

UV-sensitivity and repair of UV-damage in Salmonella of wild type

Energy Technology Data Exchange (ETDEWEB)

Kondratiev, Y S; Brukhansky, G V; Andreeva, I V; Skavronskaya, A G [Akademiya Meditsinskikh Nauk SSSR, Moscow. Inst. Ehpidemiologii i Mikrobiologii

1977-12-01

The UV-sensitivity of wild type Salmonella strains has been compared to that of wild type E.coli and its UV-sensitive mutants. Many wild type Salmonella strains are 4-5 times more sensitive than wild type E.coli and their inactivation curve is similar to that for E.coli with a mutation in the polA gene. Alkaline sucrose gradient centrifugation has shown a deficiency of these strains in normal excision repair of UV-damaged DNA. This deficiency is not a Salmonella genus feature because one strain as resistant as wild type E.coli was found. This resistant strain showed normal excision repair in alkaline sucrose gradient centrifugation experiments. The possible influence of plasmids and mutations in repair genes on the ability of Salmonella to repair UV-damaged DNA is discussed.

Sabin and wild type polioviruses from children who presented with ...

African Journals Online (AJOL)

Conclusion: This study further confirms the presence of Sabin and wild-type poliovirus among children in Nigeria. The isolation of Sabin strain of poliovirus is advantageous to the polio eradication program as it is capable of inducing natural immunity in susceptible hosts. Transmission of wild-type poliovirus among children ...

The role of wild canids and felids in spreading parasites to dogs and cats in Europe. Part I: Protozoa and tick-borne agents.

Science.gov (United States)

Otranto, Domenico; Cantacessi, Cinzia; Pfeffer, Martin; Dantas-Torres, Filipe; Brianti, Emanuele; Deplazes, Peter; Genchi, Claudio; Guberti, Vittorio; Capelli, Gioia

2015-09-30

Over the last few decades, the world has witnessed radical changes in climate, landscape, and ecosystems. These events, together with other factors such as increasing illegal wildlife trade and changing human behaviour towards wildlife, are resulting into thinning boundaries between wild canids and felids and their domestic counterparts. As a consequence, the epidemiology of diseases caused by a number of infectious agents is undergoing profound readjustements, as pathogens adapt to new hosts and environments. Therefore, there is a risk for diseases of wildlife to spread to domestic carnivores and vice versa, and for zoonotic agents to emerge or re-emerge in human populations. Hence, the identification of the hazards arising from the co-habitation of these species is critical in order to plan and develop adequate control strategies against these pathogens. In the first of this two-part article, we review the role that wild canids and felids may play in the transmission of protozoa and arthropod-borne agents to dogs and cats in Europe, and provide an account of how current and future progress in our understanding of the ecology and epidemiology of parasites, as well as of host-parasite interactions, can assist efforts aimed at controlling parasite transmission. Copyright © 2015 Elsevier B.V. All rights reserved.

Experimental demonstration of a parasite-induced immune response in wild birds: Darwin's finches and introduced nest flies.

Science.gov (United States)

Koop, Jennifer A H; Owen, Jeb P; Knutie, Sarah A; Aguilar, Maria A; Clayton, Dale H

2013-08-01

Ecological immunology aims to explain variation among hosts in the strength and efficacy of immunological defenses. However, a shortcoming has been the failure to link host immune responses to actual parasites under natural conditions. Here, we present one of the first experimental demonstrations of a parasite-induced immune response in a wild bird population. The recently introduced ectoparasitic nest fly Philornis downsi severely impacts the fitness of Darwin's finches and other land birds in the Galápagos Islands. An earlier study showed that female medium ground finches (Geospiza fortis) had P. downsi-binding antibodies correlating with presumed variation in fly exposure over time. In the current study, we experimentally manipulated fly abundance to test whether the fly does, in fact, cause changes in antibody levels. We manipulated P. downsi abundance in nests and quantified P. downsi-binding antibody levels of medium ground finch mothers, fathers, and nestlings. We also quantified host behaviors, such as preening, which can integrate with antibody-mediated defenses against ectoparasites. Philornis downsi-binding antibody levels were significantly higher among mothers at parasitized nests, compared to mothers at (fumigated) nonparasitized nests. Mothers with higher antibody levels tended to have fewer parasites in their nests, suggesting that antibodies play a role in defense against parasites. Mothers showed no behavioral changes that would enhance the effectiveness of the immune response. Neither adult males, nor nestlings, had P. downsi-induced immunological or behavioral responses that would enhance defense against flies. None of the parasitized nests fledged any offspring, despite the immune response by mothers. Thus, this study shows that, while the immune response of mothers appeared to be defensive, it was not sufficient to rescue current reproductive fitness. This study further shows the importance of testing the fitness consequences of immune

Toxoplasma gondii coinfection with diseases and parasites in wild rabbits in Scotland.

Science.gov (United States)

Mason, Sam; Dubey, J P; Smith, Judith E; Boag, Brian

2015-09-01

In wild rabbits (Oryctolagus cuniculus) on an estate in Perthshire, central Scotland, the seroprevalence of Toxoplasma gondii was 18/548 (3·3%). The wild rabbit could be a T. gondii reservoir and it has potential value as a sentinel of T. gondii in environmental substrates. Toxoplasma gondii was associated with female sex (P myxomatosis caused by the virus Myxomatosis cuniculi, the intensity of roundworm eggs, the year or season, rabbit age or distance from farm buildings. Coinfections could have been affected by gestational down regulation of type 1 T helper cells. A sudden influx or release of T. gondii oocysts might have occurred. This is the first report of T. gondii in any wild herbivore in Scotland and also the first report of lapine T. gondii as a coinfection with E. stiedae, M. cuniculi and helminths.

Imidazolopiperazines (IPZ) kill both rings and dormant rings in wild type and K13 artemisinin resistant Plasmodium falciparum in vitro.

Science.gov (United States)

Dembele, Laurent; Gupta, Devendra Kumar; Lim, Michelle Yi-Xiu; Ang, Xiaoman; Selva, Jeremy J; Chotivanich, Kesinee; Nguon, Chea; Dondorp, Arjen M; Bonamy, Ghislain M C; Diagana, Thierry T; Bifani, Pablo

2018-03-12

Artemisinin (ART) resistance has spread through Southeast Asia, posing serious threat to the control and elimination of malaria. ART resistance has been associated with mutations in the Plasmodium falciparum kelch-13 ( Pfk13 ) propeller domain. Phenotypically, ART resistance is defined as delayed parasite clearance in patients' due to the reduced susceptibility of early ring-stage parasites to the active metabolite of ART dihydroartemisinin (DHA). Early rings can enter a state of quiescence upon DHA exposure and resume growth in its absence. These quiescent rings are referred to as dormant rings or DHA-pretreated rings (called here dormant rings). The imidazolopiperazine (IPZ) is a novel class of antimalarial drugs, which has demonstrated efficacy in early clinical trials. Here, we characterized the stage of action of IPZ GNF179 and evaluated its activity against rings and dormant rings in wild type and ART resistant parasites. Unlike DHA, GNF179 does not induce dormancy. We show that GNF179 is more rapidly cidal against schizonts than ring and trophozoite stages. However, with 12 hours exposure, the compound effectively kills rings and dormant rings of both susceptible and ART resistant parasites within 72 hours. We further demonstrate that in combination with ART, GNF179 effectively prevent recrudescence of dormant rings including those bearing pfk13 propeller mutations. Copyright © 2018 Dembele et al.

From Parasite Encounter to Infection: Multiple-Scale Drivers of Parasite Richness in a Wild Social Primate Population

Science.gov (United States)

Benavides J. A.; Huchard, E.; Pettorelli, N.; King, A. J.; Brown, M. E.; Archer, C. E.; Appleton, C. C.; Raymond, M.; Cowlishaw, G.

2011-01-01

Host parasite diversity plays a fundamental role in ecological and evolutionary processes, yet the factors that drive it are still poorly understood. A variety of processes, operating across a range of spatial scales, are likely to influence both the probability of parasite encounter and subsequent infection. Here, we explored eight possible determinants of parasite richness, comprising rainfall and temperature at the population level, ranging behavior and home range productivity at the group level, and age, sex, body condition, and social rank at the individual level. We used a unique dataset describing gastrointestinal parasites in a terrestrial subtropical vertebrate (chacma baboons, Papio ursinus), comprising 662 faecal samples from 86 individuals representing all age-sex classes across two groups over two dry seasons in a desert population. Three mixed models were used to identify the most important factor at each of the three spatial scales (population, group, individual); these were then standardised and combined in a single, global, mixed model. Individual age had the strongest influence on parasite richness, in a convex relationship. Parasite richness was also higher in females and animals in poor condition, albeit at a lower order of magnitude than age. Finally, with a further halving of effect size, parasite richness was positively correlated to day range and temperature. These findings indicate that a range of factors influence host parasite richness through both encounter and infection probabilities, but that individual-level processes may be more important than those at the group or population level.

Parasitic helminths and their beneficial impact on type 1 and type 2 diabetes.

Science.gov (United States)

Berbudi, Afiat; Ajendra, Jesuthas; Wardani, Ajeng P F; Hoerauf, Achim; Hübner, Marc P

2016-03-01

It is estimated that by the year 2035 almost 600 million people will suffer from diabetes. In the case of type 2 diabetes, the strongest increase of diabetes incidence occurs in developing and newly industrialized countries. This increase correlates not only with a progressing sedentary lifestyle and nutritional changes, but also environmental changes. Similarly, the increase of type 1 diabetes incidence in industrialized countries over the past decades cannot be explained by genetic factors alone, suggesting that environmental changes are also involved. One such environmental change is a reduced exposure to pathogens because of improved hygiene. Parasitic helminths modulate the immune system of their hosts and induce type 2 as well as regulatory immune responses. As pro-inflammatory immune responses are crucial for the onset of both type 1 and type 2 diabetes, helminth-induced immunomodulation may prevent diabetes onset and ameliorate insulin sensitivity. Several epidemiological studies in human and experimental animal models support such a protective effect of helminths for autoimmune diabetes. Recent studies further suggest that helminths may also provide such a beneficial effect for type 2 diabetes. In this review we summarize studies that investigated parasitic helminths and helminth-derived products and their impact on both type 1 and type 2 diabetes highlighting potential protective mechanisms. Copyright © 2015 John Wiley & Sons, Ltd.

Parasites of domestic and wild animals in South Africa. XLIV. Fleas (Insecta : Siphonaptera : Pulicidae collected from 15 carnivore species

Directory of Open Access Journals (Sweden)

I.G. Horak

2004-11-01

Full Text Available Fleas were collected from 61 wild carnivores belonging to 13 species in various nature reserves and on farms, two feral domestic cats in a nature reserve and a domestic dog in the city of Johannesburg. Eleven flea species, including two subspecies of one of these, belonging to six genera were recovered. Amongst these only Ctenocephalides felis felis and Ctenocephalides felis strongylus are considered specific parasites of carnivores. The remaining ten species normally infest the prey animals of the various carnivores.

Ichthyophonus parasite phylogeny based on ITS rDNA structure prediction and alignment identifies six clades, with a single dominant marine type

Science.gov (United States)

Gregg, Jacob; Thompson, Rachel L.; Purcell, Maureen; Friedman, Carolyn S.; Hershberger, Paul

2016-01-01

Despite their widespread, global impact in both wild and cultured fishes, little is known of the diversity, transmission patterns, and phylogeography of parasites generally identified as Ichthyophonus. This study constructed a phylogeny based on the structural alignment of internal transcribed spacer (ITS) rDNA sequences to compare Ichthyophonus isolates from fish hosts in the Atlantic and Pacific oceans, and several rivers and aquaculture sites in North America, Europe, and Japan. Structure of the Ichthyophonus ITS1–5.8S–ITS2 transcript exhibited several homologies with other eukaryotes, and 6 distinct clades were identified within Ichthyophonus. A single clade contained a majority (71 of 98) of parasite isolations. This ubiquitous Ichthyophonus type occurred in 13 marine and anadromous hosts and was associated with epizootics in Atlantic herring, Chinook salmon, and American shad. A second clade contained all isolates from aquaculture, despite great geographic separation of the freshwater hosts. Each of the 4 remaining clades contained isolates from single host species. This study is the first to evaluate the genetic relationships among Ichthyophonus species across a significant portion of their host and geographic range. Additionally, parasite infection prevalence is reported in 16 fish species.

Ichthyophonus parasite phylogeny based on ITS rDNA structure prediction and alignment identifies six clades, with a single dominant marine type.

Science.gov (United States)

Gregg, Jacob L; Powers, Rachel L; Purcell, Maureen K; Friedman, Carolyn S; Hershberger, Paul K

2016-07-07

Despite their widespread, global impact in both wild and cultured fishes, little is known of the diversity, transmission patterns, and phylogeography of parasites generally identified as Ichthyophonus. This study constructed a phylogeny based on the structural alignment of internal transcribed spacer (ITS) rDNA sequences to compare Ichthyophonus isolates from fish hosts in the Atlantic and Pacific oceans, and several rivers and aquaculture sites in North America, Europe, and Japan. Structure of the Ichthyophonus ITS1-5.8S-ITS2 transcript exhibited several homologies with other eukaryotes, and 6 distinct clades were identified within Ichthyophonus. A single clade contained a majority (71 of 98) of parasite isolations. This ubiquitous Ichthyophonus type occurred in 13 marine and anadromous hosts and was associated with epizootics in Atlantic herring, Chinook salmon, and American shad. A second clade contained all isolates from aquaculture, despite great geographic separation of the freshwater hosts. Each of the 4 remaining clades contained isolates from single host species. This study is the first to evaluate the genetic relationships among Ichthyophonus species across a significant portion of their host and geographic range. Additionally, parasite infection prevalence is reported in 16 fish species.

The relationship between managed bees and the prevalence of parasites in bumblebees.

Science.gov (United States)

Graystock, Peter; Goulson, Dave; Hughes, William O H

2014-01-01

Honey bees and, more recently, bumblebees have been domesticated and are now managed commercially primarily for crop pollination, mixing with wild pollinators during foraging on shared flower resources. There is mounting evidence that managed honey bees or commercially produced bumblebees may affect the health of wild pollinators such as bumblebees by increasing competition for resources and the prevalence of parasites in wild bees. Here we screened 764 bumblebees from around five greenhouses that either used commercially produced bumblebees or did not, as well as bumblebees from 10 colonies placed at two sites either close to or far from a honey bee apiary, for the parasites Apicystis bombi, Crithidia bombi, Nosema bombi, N. ceranae, N. apis and deformed wing virus. We found that A. bombi and C. bombi were more prevalent around greenhouses using commercially produced bumblebees, while C. bombi was 18% more prevalent in bumblebees at the site near to the honey bee apiary than those at the site far from the apiary. Whilst these results are from only a limited number of sites, they support previous reports of parasite spillover from commercially produced bumblebees to wild bumblebees, and suggest that the impact of stress from competing with managed bees or the vectoring of parasites by them on parasite prevalence in wild bees needs further investigation. It appears increasingly likely that the use of managed bees comes at a cost of increased parasites in wild bumblebees, which is not only a concern for bumblebee conservation, but which may impact other pollinators as well.

The relationship between managed bees and the prevalence of parasites in bumblebees

Directory of Open Access Journals (Sweden)

Peter Graystock

2014-08-01

Full Text Available Honey bees and, more recently, bumblebees have been domesticated and are now managed commercially primarily for crop pollination, mixing with wild pollinators during foraging on shared flower resources. There is mounting evidence that managed honey bees or commercially produced bumblebees may affect the health of wild pollinators such as bumblebees by increasing competition for resources and the prevalence of parasites in wild bees. Here we screened 764 bumblebees from around five greenhouses that either used commercially produced bumblebees or did not, as well as bumblebees from 10 colonies placed at two sites either close to or far from a honey bee apiary, for the parasites Apicystis bombi, Crithidia bombi, Nosema bombi, N. ceranae, N. apis and deformed wing virus. We found that A. bombi and C. bombi were more prevalent around greenhouses using commercially produced bumblebees, while C. bombi was 18% more prevalent in bumblebees at the site near to the honey bee apiary than those at the site far from the apiary. Whilst these results are from only a limited number of sites, they support previous reports of parasite spillover from commercially produced bumblebees to wild bumblebees, and suggest that the impact of stress from competing with managed bees or the vectoring of parasites by them on parasite prevalence in wild bees needs further investigation. It appears increasingly likely that the use of managed bees comes at a cost of increased parasites in wild bumblebees, which is not only a concern for bumblebee conservation, but which may impact other pollinators as well.

Functional characterization of malaria parasites deficient in the K⁺ channel Kch2

DEFF Research Database (Denmark)

Ellekvist, Peter; Mlambo, Godfree; Kumar, Nirbhay

2017-01-01

parasite P. berghei, the functional significance of K+ channel homologue PbKch2 was studied using targeted gene knock-out. The knockout parasites were characterized in a mouse model in terms of growth-kinetics and infectivity in the mosquito vector. Furthermore, using a tracer-uptake technique with 86Rb...... of forming oocysts in female Anopheles stephensi mosquitoes. 86Rb+ uptake in Kch2-deficient blood-stage P. berghei parasites (Kch2-null) did not differ from that of wild-type (WT) parasites. About two-thirds of the 86Rb+ uptake in WT and in Kch2-null parasites could be inhibited by K+ channel blockers...... and could be inferred to the presence of functional Kch1 in Kch2 knockout parasites. Kch2 is therefore not required for transport of K+ in P. berghei and is not essential to mosquito-stage sporogonic development of the parasite....

The effect of parasites on wildlife

NARCIS (Netherlands)

Borgsteede, F.H.M.

1996-01-01

Populations of animals which live in the wild are regulated by many biotic and abiotic factors. Parasites are one of the biotic factors. Parasites may influence their hosts in different ways. They may cause the death of the host due to a direct lethal effect or an indirect effect. Direct lethal

Transgenic Expression of the Anti-parasitic Factor TEP1 in the Malaria Mosquito Anopheles gambiae.

Directory of Open Access Journals (Sweden)

Gloria Volohonsky

2017-01-01

Full Text Available Mosquitoes genetically engineered to be resistant to Plasmodium parasites represent a promising novel approach in the fight against malaria. The insect immune system itself is a source of anti-parasitic genes potentially exploitable for transgenic designs. The Anopheles gambiae thioester containing protein 1 (TEP1 is a potent anti-parasitic protein. TEP1 is secreted and circulates in the mosquito hemolymph, where its activated cleaved form binds and eliminates malaria parasites. Here we investigated whether TEP1 can be used to create malaria resistant mosquitoes. Using a GFP reporter transgene, we determined that the fat body is the main site of TEP1 expression. We generated transgenic mosquitoes that express TEP1r, a potent refractory allele of TEP1, in the fat body and examined the activity of the transgenic protein in wild-type or TEP1 mutant genetic backgrounds. Transgenic TEP1r rescued loss-of-function mutations, but did not increase parasite resistance in the presence of a wild-type susceptible allele. Consistent with previous reports, TEP1 protein expressed from the transgene in the fat body was taken up by hemocytes upon a challenge with injected bacteria. Furthermore, although maturation of transgenic TEP1 into the cleaved form was impaired in one of the TEP1 mutant lines, it was still sufficient to reduce parasite numbers and induce parasite melanization. We also report here the first use of Transcription Activator Like Effectors (TALEs in Anopheles gambiae to stimulate expression of endogenous TEP1. We found that artificial elevation of TEP1 expression remains moderate in vivo and that enhancement of endogenous TEP1 expression did not result in increased resistance to Plasmodium. Taken together, our results reveal the difficulty of artificially influencing TEP1-mediated Plasmodium resistance, and contribute to further our understanding of the molecular mechanisms underlying mosquito resistance to Plasmodium parasites.

Effects of environmental variation on host-parasite interaction in three-spined sticklebacks (Gasterosteus aculeatus).

Science.gov (United States)

Scharsack, Jörn P; Franke, Frederik; Erin, Noémi I; Kuske, Andra; Büscher, Janine; Stolz, Hendrik; Samonte, Irene E; Kurtz, Joachim; Kalbe, Martin

2016-08-01

Recent research provides accumulating evidence that the evolutionary dynamics of host-parasite adaptations strongly depend on environmental variation. In this context, the three-spined stickleback (Gasterosteus aculeatus) has become an important research model since it is distributed all over the northern hemisphere and lives in very different habitat types, ranging from marine to freshwater, were it is exposed to a huge diversity of parasites. While a majority of studies start from explorations of sticklebacks in the wild, only relatively few investigations have continued under laboratory conditions. Accordingly, it has often been described that sticklebacks differ in parasite burden between habitats, but the underlying co-evolutionary trajectories are often not well understood. With the present review, we give an overview of the most striking examples of stickleback-parasite-environment interactions discovered in the wild and discuss two model parasites which have received some attention in laboratory studies: the eye fluke Diplostomum pseudospathacaeum, for which host fish show habitat-specific levels of resistance, and the tapeworm Schistocephalus solidus, which manipulates immunity and behavior of its stickleback host to its advantage. Finally, we will concentrate on an important environmental variable, namely temperature, which has prominent effects on the activity of the immune system of ectothermic hosts and on parasite growth rates. Copyright © 2016 The Authors. Published by Elsevier GmbH.. All rights reserved.

Characterization and Function of the Inflammatory Response to Infection by a Gastrointestinal Nematode Parasite: New Insights into Protective Th2 Responses

Science.gov (United States)

2006-01-01

gastrointestinal nematode parasites;T. trichuris, T. muris , T suis. WT wild type. 1 Dissertation Introduction Background and Significance...and hosts2. Infectious parasites are responsible for a wide range of human diseases, including Leishmanisis, Malaria, Schistosomaisis, Giardia ...the gut to define more clearly protective mechanisms against gastrointestinal nematodes. Using a mouse whipworm model of Trichuris 81 muris

The Genetic Structure of Wild Orobanche cumana Wallr. (Orobanchaceae Populations in Eastern Bulgaria Reflects Introgressions from Weedy Populations

Directory of Open Access Journals (Sweden)

Rocío Pineda-Martos

2014-01-01

Full Text Available Orobanche cumana is a holoparasitic plant naturally distributed from central Asia to south-eastern Europe, where it parasitizes wild Asteraceae species. It is also an important parasitic weed of sunflower crops. The objective of this research was to investigate genetic diversity, population structure, and virulence on sunflower of O. cumana populations parasitizing wild plants in eastern Bulgaria. Fresh tissue of eight O. cumana populations and mature seeds of four of them were collected in situ on wild hosts. Genetic diversity and population structure were studied with SSR markers and compared to weedy populations. Two main gene pools were identified in Bulgarian populations, with most of the populations having intermediate characteristics. Cross-inoculation experiments revealed that O. cumana populations collected on wild species possessed similar ability to parasitize sunflower to those collected on sunflower. The results were explained on the basis of an effective genetic exchange between populations parasitizing sunflower crops and those parasitizing wild species. The occurrence of bidirectional gene flow may have an impact on wild populations, as new physiological races continuously emerge in weedy populations. Also, genetic variability of wild populations may favour the ability of weedy populations to overcome sunflower resistance mechanisms.

The Genetic Structure of Wild Orobanche cumana Wallr. (Orobanchaceae) Populations in Eastern Bulgaria Reflects Introgressions from Weedy Populations

Science.gov (United States)

Pineda-Martos, Rocío; Pujadas-Salvà, Antonio J.; Fernández-Martínez, José M.; Stoyanov, Kiril; Pérez-Vich, Begoña

2014-01-01

Orobanche cumana is a holoparasitic plant naturally distributed from central Asia to south-eastern Europe, where it parasitizes wild Asteraceae species. It is also an important parasitic weed of sunflower crops. The objective of this research was to investigate genetic diversity, population structure, and virulence on sunflower of O. cumana populations parasitizing wild plants in eastern Bulgaria. Fresh tissue of eight O. cumana populations and mature seeds of four of them were collected in situ on wild hosts. Genetic diversity and population structure were studied with SSR markers and compared to weedy populations. Two main gene pools were identified in Bulgarian populations, with most of the populations having intermediate characteristics. Cross-inoculation experiments revealed that O. cumana populations collected on wild species possessed similar ability to parasitize sunflower to those collected on sunflower. The results were explained on the basis of an effective genetic exchange between populations parasitizing sunflower crops and those parasitizing wild species. The occurrence of bidirectional gene flow may have an impact on wild populations, as new physiological races continuously emerge in weedy populations. Also, genetic variability of wild populations may favour the ability of weedy populations to overcome sunflower resistance mechanisms. PMID:25143963

Identification of trypanosomes in wild animals from Southern Cameroon using the polymerase chain reaction (PCR

Directory of Open Access Journals (Sweden)

Herder S.

2002-12-01

Full Text Available One possible explanation of the maintenance of many historical foci of sleeping sickness in Central Africa could be the existence of a wild animal reservoir. In this study, PCR was used to detect the different trypanosome species present in wild animal captured by hunters in the southern forest belt of Cameroon (Bipindi. Trypanosomes were also detected by a parasitological method (Quantitative buffy coat : QBC. Parasite could not be isolated in culture medium (Kit for in vitro isolation : KIVI. Specific primers of T. brucei s.l., T. congolense forest type, T. congolense savannah type, T. vivax, T. simiae and T. b. gambiense group 1 were used to identify parasites in the blood of 164 animals belonging to 24 different species including ungulates, rodents, pangolins, carnivores, reptiles and primates. Of the 24 studied species, eight were carrying T. b. gambiense group 1. Those parasites pathogenic to man were found in monkeys (Cercocebus torquatus and Cercopithecus nictitans, in ungulates (Cephalophus dorsalis and C. monticola, in carnivores (Nandinia binotata and Genetta servalina and in rodents (Cricetomys gambianus and Atherurus africanus. 13 species (54 % were carrying T. brucei s.l. identified as non-gambiense group 1.

Parasites and associated packed cell volume changes of captive ...

African Journals Online (AJOL)

The results revealed that out of the 126 captive wild birds examined during the period, 98 (77.8%) were infected with at least one parasite species. Arthropod parasites were encountered in 63 (34.1%) birds and the parasites recovered were Echidnophaga gallinacea (27.0%), Argas persicus (18.2%) and Ctnemidocoptes ...

Activation Of Wild-Type Hras Suppresses The Earliest Stages Of Pancreatic Cancer

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Jamie Weyandt

2015-08-01

Conclusions: Loss of wild-type Hras promotes the earliest stages of pancreatic tumorigenesis, and moreover results in more rapid progression of the disease. As such, mechanisms leading to activation of wild-type Ras proteins, including but not limited to redox-dependent reactions, may influence the development of pancreatic cancer.

Museum samples reveal rapid evolution by wild honey bees exposed to a novel parasite.

Science.gov (United States)

Mikheyev, Alexander S; Tin, Mandy M Y; Arora, Jatin; Seeley, Thomas D

2015-08-06

Understanding genetic changes caused by novel pathogens and parasites can reveal mechanisms of adaptation and genetic robustness. Using whole-genome sequencing of museum and modern specimens, we describe the genomic changes in a wild population of honey bees in North America following the introduction of the ectoparasitic mite, Varroa destructor. Even though colony density in the study population is the same today as in the past, a major loss of haplotypic diversity occurred, indicative of a drastic mitochondrial bottleneck, caused by massive colony mortality. In contrast, nuclear genetic diversity did not change, though hundreds of genes show signs of selection. The genetic diversity within each bee colony, particularly as a consequence of polyandry by queens, may enable preservation of genetic diversity even during population bottlenecks. These findings suggest that genetically diverse honey bee populations can recover from introduced diseases by evolving rapid tolerance, while maintaining much of the standing genetic variation.

Gastrointestinal and blood parasite determination in the guanaco (Lama guanicoe) under semi-captivity conditions.

Science.gov (United States)

Correa, Loreto; Zapata, Beatriz; Soto-Gamboa, Mauricio

2012-01-01

The breeding of wild animals for commercial purposes is becoming more frequent nowadays. This situation has led to an increase in contact rates between wild and domestic animals, with subsequent reciprocal transmission of parasites. In this study, we characterized the gastrointestinal and blood parasites of a group of 15 semi-captive guanacos (Lama guanicoe). We characterized gastrointestinal parasites by analyzing fecal samples through the sedimentation-flotation technique and hemoparasites by using blood smears stained with Giemsa. We found several gastrointestinal parasites including Nematoda and protozoans. The most frequently found parasites were Nematodirus sp. and Eimeria sp. In contrast with previous studies, neither Cestoda nor Fasciola were found. The only hemoparasite detected was Mycoplasma haemolamae, a parasite already described in llamas and alpacas. We conclude that the most frequent gastrointestinal parasites of semi-captive guanacos were nematodes and protozoans. Also, the hemoparasite M. haemolamae seems to be prevalent among captive populations of South American camelids. Finally, captive guanacos share several parasites with the traditional livestock. Therefore, keeping captive or semi-captive guanacos without an adequate sanitary protocol might have adverse consequences to adjacent traditional cattle farming and/or for wild animals.

Unbiased RNA Shotgun Metagenomics in Social and Solitary Wild Bees Detects Associations with Eukaryote Parasites and New Viruses.

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Karel Schoonvaere

Full Text Available The diversity of eukaryote organisms and viruses associated with wild bees remains poorly characterized in contrast to the well-documented pathosphere of the western honey bee, Apis mellifera. Using a deliberate RNA shotgun metagenomic sequencing strategy in combination with a dedicated bioinformatics workflow, we identified the (micro-organisms and viruses associated with two bumble bee hosts, Bombus terrestris and Bombus pascuorum, and two solitary bee hosts, Osmia cornuta and Andrena vaga. Ion Torrent semiconductor sequencing generated approximately 3.8 million high quality reads. The most significant eukaryote associations were two protozoan, Apicystis bombi and Crithidia bombi, and one nematode parasite Sphaerularia bombi in bumble bees. The trypanosome protozoan C. bombi was also found in the solitary bee O. cornuta. Next to the identification of three honey bee viruses Black queen cell virus, Sacbrood virus and Varroa destructor virus-1 and four plant viruses, we describe two novel RNA viruses Scaldis River bee virus (SRBV and Ganda bee virus (GABV based on their partial genomic sequences. The novel viruses belong to the class of negative-sense RNA viruses, SRBV is related to the order Mononegavirales whereas GABV is related to the family Bunyaviridae. The potential biological role of both viruses in bees is discussed in the context of recent advances in the field of arthropod viruses. Further, fragmentary sequence evidence for other undescribed viruses is presented, among which a nudivirus in O. cornuta and an unclassified virus related to Chronic bee paralysis virus in B. terrestris. Our findings extend the current knowledge of wild bee parasites in general and addsto the growing evidence of unexplored arthropod viruses in valuable insects.

Unbiased RNA Shotgun Metagenomics in Social and Solitary Wild Bees Detects Associations with Eukaryote Parasites and New Viruses.

Science.gov (United States)

Schoonvaere, Karel; De Smet, Lina; Smagghe, Guy; Vierstraete, Andy; Braeckman, Bart P; de Graaf, Dirk C

2016-01-01

The diversity of eukaryote organisms and viruses associated with wild bees remains poorly characterized in contrast to the well-documented pathosphere of the western honey bee, Apis mellifera. Using a deliberate RNA shotgun metagenomic sequencing strategy in combination with a dedicated bioinformatics workflow, we identified the (micro-)organisms and viruses associated with two bumble bee hosts, Bombus terrestris and Bombus pascuorum, and two solitary bee hosts, Osmia cornuta and Andrena vaga. Ion Torrent semiconductor sequencing generated approximately 3.8 million high quality reads. The most significant eukaryote associations were two protozoan, Apicystis bombi and Crithidia bombi, and one nematode parasite Sphaerularia bombi in bumble bees. The trypanosome protozoan C. bombi was also found in the solitary bee O. cornuta. Next to the identification of three honey bee viruses Black queen cell virus, Sacbrood virus and Varroa destructor virus-1 and four plant viruses, we describe two novel RNA viruses Scaldis River bee virus (SRBV) and Ganda bee virus (GABV) based on their partial genomic sequences. The novel viruses belong to the class of negative-sense RNA viruses, SRBV is related to the order Mononegavirales whereas GABV is related to the family Bunyaviridae. The potential biological role of both viruses in bees is discussed in the context of recent advances in the field of arthropod viruses. Further, fragmentary sequence evidence for other undescribed viruses is presented, among which a nudivirus in O. cornuta and an unclassified virus related to Chronic bee paralysis virus in B. terrestris. Our findings extend the current knowledge of wild bee parasites in general and addsto the growing evidence of unexplored arthropod viruses in valuable insects.

Gastrointestinal parasites of canids, a latent risk to human health in Tunisia.

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Oudni-M'rad, Myriam; Chaâbane-Banaoues, Raja; M'rad, Selim; Trifa, Fatma; Mezhoud, Habib; Babba, Hamouda

2017-06-05

Although data on the parasite environmental contamination are crucial to implement strategies for control and treatment, information about zoonotic helminths is very limited in Tunisia. Contamination of areas with canid faeces harboring infective parasite elements represents a relevant health-risk impact for humans. The aim of this study was to assess the environmental contamination with eggs and oocysts of gastrointestinal parasites of dogs and wild canids in Tunisia with special attention to those that can be transmitted to humans. One thousand two hundred and seventy faecal samples from stray dogs and 104 from wild canids (red foxes and golden jackals) were collected from different geographical regions throughout Tunisia. The helminth eggs and protozoan oocysts were concentrated by sucrose flotation and identified by microscopic examination. The most frequently observed parasites in dog samples were Toxocara spp. (27.2%), E. granulosus (25.8%), and Coccidia (13.1%). For wild canid faeces, the most commonly encountered parasites were Toxocara spp. (16.3%) followed by Capillaria spp. (9.6%). The parasite contamination of dog faeces varied significantly from one region to another in function of the climate. To our knowledge, the study highlights for the first time in Tunisia a serious environmental contamination by numerous parasitic stages infective to humans. Efforts should be made to increase the awareness of the contamination risk of such parasites in the environment and implement a targeted educational program.

Epidemiological study of the intestinal helminths of wild boar (Sus scrofa) and mouflon (Ovis gmelini musimon) in central Italy.

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Magi, M; Bertani, M; Dell'Omodarme, M; Prati, M C

2002-12-01

Since 1995 the population of wild ungulates increased significantly in the "Parco provinciale dei Monti Livornesi" (Livorno, Tuscany, Central Italy). We studied the intestinal macroparasites of two hosts, the wild boar (Sus scrofa) and the mouflon (Ovis gmelini musimon). In the case of wild boars we found a dominant parasite species, Globocephalus urosubulatus. For this parasite the frequency distribution of the number of parasites per host agrees with a negative binomial distribution. There is not a significant correlation between the age of the animals and the parasitosis. Furthermore the mean parasite burden of male and female wild boars does not differ significantly. In the case of mouflons we found a dominant parasite species Nematodirus filicollis with Trichuris ovis as codominant species.

Museum samples reveal rapid evolution by wild honey bees exposed to a novel parasite

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Mikheyev, Alexander S.; Tin, Mandy M. Y.; Arora, Jatin; Seeley, Thomas D.

2015-01-01

Understanding genetic changes caused by novel pathogens and parasites can reveal mechanisms of adaptation and genetic robustness. Using whole-genome sequencing of museum and modern specimens, we describe the genomic changes in a wild population of honey bees in North America following the introduction of the ectoparasitic mite, Varroa destructor. Even though colony density in the study population is the same today as in the past, a major loss of haplotypic diversity occurred, indicative of a drastic mitochondrial bottleneck, caused by massive colony mortality. In contrast, nuclear genetic diversity did not change, though hundreds of genes show signs of selection. The genetic diversity within each bee colony, particularly as a consequence of polyandry by queens, may enable preservation of genetic diversity even during population bottlenecks. These findings suggest that genetically diverse honey bee populations can recover from introduced diseases by evolving rapid tolerance, while maintaining much of the standing genetic variation. PMID:26246313

Global Mammal Parasite Database version 2.0.

Science.gov (United States)

Stephens, Patrick R; Pappalardo, Paula; Huang, Shan; Byers, James E; Farrell, Maxwell J; Gehman, Alyssa; Ghai, Ria R; Haas, Sarah E; Han, Barbara; Park, Andrew W; Schmidt, John P; Altizer, Sonia; Ezenwa, Vanessa O; Nunn, Charles L

2017-05-01

Illuminating the ecological and evolutionary dynamics of parasites is one of the most pressing issues facing modern science, and is critical for basic science, the global economy, and human health. Extremely important to this effort are data on the disease-causing organisms of wild animal hosts (including viruses, bacteria, protozoa, helminths, arthropods, and fungi). Here we present an updated version of the Global Mammal Parasite Database, a database of the parasites of wild ungulates (artiodactyls and perissodactyls), carnivores, and primates, and make it available for download as complete flat files. The updated database has more than 24,000 entries in the main data file alone, representing data from over 2700 literature sources. We include data on sampling method and sample sizes when reported, as well as both "reported" and "corrected" (i.e., standardized) binomials for each host and parasite species. Also included are current higher taxonomies and data on transmission modes used by the majority of species of parasites in the database. In the associated metadata we describe the methods used to identify sources and extract data from the primary literature, how entries were checked for errors, methods used to georeference entries, and how host and parasite taxonomies were standardized across the database. We also provide definitions of the data fields in each of the four files that users can download. © 2017 by the Ecological Society of America.

Surveys on Gyrodactylus parasites onwild Atlantic salmon in Denmark

DEFF Research Database (Denmark)

Jørgensen, Louise von Gersdorff; Heinecke, Rasmus Demuth; Buchmann, Kurt

Gyrodactylus salaris is a monogenean ectoparasite parasitizing salmonids in freshwater. This parasite is highly pathogenic to both Norwegian and Scottish salmon and has decimated the salmon populations in 45 Norwegian rivers after anthropogenic transfer from Sweden. G. salaris has also been found...... on several occasions in Danish rainbow trout farms but has never been recorded as a pathogenic parasite on Danish wild salmon. In the present study the occurrence of G. salaris and other Gyrodactylus parasites on wild Danish salmon fry and parr were monitored. Electrofishing was conducted in three river......-systems (River Skjern, Ribe and Varde) and 0+ and 1+ salmon were collected and sacrificed using an overdose of MS222. During spring or summer time more salmon fry and parr will be collected. The fins were excised and fins and body were conserved separately in 96% ethanol. In the laboratory, the fins and body...

Host-Parasite Interactions in Individuals with Type 1 and 2 Diabetes Result in Higher Frequency of Ascaris lumbricoides and Giardia lamblia in Type 2 Diabetic Individuals

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Eleuza Rodrigues Machado

2018-01-01

Full Text Available Host-parasite interactions in diabetic patients might influence diabetes complications and intestinal parasitosis. The aim was to investigate the occurrence of enteroparasites in individuals with diabetes types 1 and 2. A descriptive study was designed to estimate frequencies of parasites and to compare them in individuals with diabetes types 1 and 2 from two Health Centers and one hospital in the Federal District of Brazil. Patients were allocated to the study by convenience. Three fecal samples of 156 diabetic individuals (120 type 1 and 36 type 2 were analyzed using two parasitological methods. Enteroparasites or commensals frequency in diabetics was 64%. Diabetics infected with up to six species of intestinal parasites or commensals were found. Frequencies of Ascaris lumbricoides and Giardia lamblia were higher in individuals with type 2 diabetes. The lower frequency of A. lumbricoides found in type 1 diabetes may be related to a strong Th2 response to parasites. Autoimmune response developed in type 1 diabetic individuals characterized by the production of Th1 cytokines could explain low frequency of G. lamblia. High frequency of parasites found in type 2 diabetes emphasizes the importance of periodic parasitological examinations in these individuals.

Comparative behaviour of lab.-cultured and wild-type Dacus oleae flies in the field

International Nuclear Information System (INIS)

Prokopy, R.J.; Haniotakis, G.E.; Economopoulos, A.P.

1975-01-01

Under field conditions, the authors compared the responses of lab.-type (ca. 85 generations under artificial conditions) and wild-type Dacus oleae flies to host plant colour and odour, host fruit colour and shape, small rectangles of different colours and shades, and McPhail-type traps of different colours baited with different odours. Except for the lab.-type flies being relatively more attracted toward red fruit models and small red rectangles and relatively less attracted toward yellow fruit models and small yellow rectangles than the wild type, the qualitative nature of the responses of the two fly types toward the various experimental treatments was essentially the same. Quantitatively, however, consistently smaller percentages of the released lab.-type than the released wild-type flies were recaptured, suggesting that the mobility, flight pattern, or vigour of the two types of flies may be different. (author)

Structure and Composition of Protein Bodies from Wild-Type and High-Lysine Barley Endosperm

DEFF Research Database (Denmark)

Ingversen, J.

1975-01-01

Protein bodies were isolated from 13 and 28 day old endosperms of barley mutant 1508 and its wild type, Bomi barley. The fine structure of the isolated protein bodies was determined by electron microscopy, and the proteins present in the preparations characterized by amino-acid analysis and SDS......-polyacrylamidegel electrophoresis. Sections through pellets of isolated protein bodies from both the mutant and the wild type revealed protein body structures corresponding with those observed in sections through the intact starchy endosperms. The majority of the wild-type protein bodies was homogeneous spheres accompanied...... that the wild-type protein bodies contained large amounts of prolamines (the storage protein group which is soluble in 55 % isopropanol) and some glutelins (the storage proteins soluble in dilute alkali), whereas the mutant protein bodies have glutelin as the major component and little prolamines...

Blood parasites from California ducks and geese

Science.gov (United States)

Herman, C.M.

1951-01-01

Blood smears were procured from 1,011 geese and ducks of 19 species from various locations in California. Parasites were found in 28 individuals. The parasites observed included Haemoproteus hermani, Leucocytozoon simondi, microfilaria, Plasmodium relictum (=P. biziurae), and Plasmodium sp. with elongate gametocytes. This is the first report of a natural infection with a Plasmodium in North American wild ducks.

PRESENCE OF TRICHINELLA BRITOVI IN WILD BOAR IN THE MARCHE REGION REGULARLY SLAUGHTERED

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L. Di Giacomo

2011-01-01

Full Text Available Trichinellosis is a zoonotic disease caused by a nematode belonging to the genus Trichinella. Numerous mammal species as well as birds and crocodiles can harbour the parasite worldwide, but the wild cycle is mainly maintained by wild carnivores. Human represents only a possible host and the parasite is exclusively transmitted through consumption of undercooked or raw meat. In Italy, pork, wild boar meat and horse meat are the main sources for human infection. This article describe a presence of Trichinella britovi in wild boar in the Marche region regularly slaughtered. These case confirms the occurrence of Trichinella britovi in wild boar and the important role of slaughterhouse in epidemiological surveillance of zoonotic diseases.

Porphyrin Interactions with Wild Type and Mutant Mouse Ferrochelatase

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Ferreira, Gloria C.; Franco, Ricardo; Lu, Yi; Ma, Jian-Guo; Shelnutt, John A.

1999-05-19

Ferrochelatase (EC 4.99.1.1), the terminal enzyme of the heme biosynthetic pathway, catalyzes Fe²⁺ chelation into protoporphyrin IX. Resonance Raman and W-visible absorbance spectroscopes of wild type and engineered variants of murine ferrochelatase were used to examine the proposed structural mechanism for iron insertion into protoporphyrin by ferrochelatase. The recombinant variants (i.e., H207N and E287Q) are enzymes in which the conserved amino acids histidine-207 and glutamate-287 of murine ferrochelatase were substituted with asparagine and glutamine, respectively. Both of these residues are at the active site of the enzyme as deduced from the Bacillus subtilis ferrochelatase three-dimensional structure. Addition of free base or metalated porphyrins to wild type ferrochelatase and H207N variant yields a quasi 1:1 complex, possibly a monomeric protein-bound species. In contrast, the addition of porphyrin (either free base or metalated) to E287Q is sub-stoichiometric, as this variant retains bound porphyrin in the active site during isolation and purification. The specificity of porphyrin binding is confirmed by the narrowing of the structure-sensitive resonance Raman lines and the vinyl vibrational mode. Resonance Raman spectra of free base and metalated porphyrins bound to the wild type ferrochelatase indicate a nonplanar distortion of the porphyrin macrocycle, although the magnitude of the distortion cannot be determined without first defining the specific type of deformation. Significantly, the extent of the nonplanar distortion varies in the case of H207N- and E287Q-bound porphyrins. In fact, resonance Raman spectral decomposition indicates a homogeneous ruffled distortion for the nickel protoporphyrin bound to the wild type ferrochelatase, whereas both a planar and ruffled conformations are present for the H207N-bound porphyrin. Perhaps more revealing is the unusual resonance , 3 Raman spectrum of the endogenous E287Q-bound porphyrin, which has

The high resolution melting analysis (HRM) as a molecular tool for monitoring parasites of the wildlife.

Science.gov (United States)

Héritier, Laurent; Verneau, Olivier; Breuil, Gregory; Meistertzheim, Anne-Leila

2017-04-01

In an interconnected world, the international pet trade on wild animals is becoming increasingly important. As a consequence, non-native parasite species are introduced, which affect the health of wildlife and contribute to the loss of biodiversity. Because the investigation of parasite diversity within vulnerable host species implies the molecular identification of large samples of parasite eggs, the sequencing of DNA barcodes is time-consuming and costly. Thereby, the objectives of our study were to apply the high resolution melting (HRM) approach for species determination from pools of parasite eggs. Molecular assays were validated on flatworm parasites (polystomes) infecting the Mediterranean pond turtle Mauremys leprosa and the invasive red-eared slider Trachemys scripta elegans in French natural environments. HRM analysis results indicated that double or multiple parasitic infections could be detected from wild animal populations. They also showed that the cycle of parasite eggs production was not regular over time and may depend on several factors, among which the ecological niche and the target species. Thereby, monitoring parasites from wild endangered animals implies periodic parasitological surveys to avoid false negative diagnostics, based solely on eggs production.

Parasitism by Cuscuta pentagona attenuates host plant defenses against insect herbivores.

Science.gov (United States)

Runyon, Justin B; Mescher, Mark C; De Moraes, Consuelo M

2008-03-01

Considerable research has examined plant responses to concurrent attack by herbivores and pathogens, but the effects of attack by parasitic plants, another important class of plant-feeding organisms, on plant defenses against other enemies has not been explored. We investigated how attack by the parasitic plant Cuscuta pentagona impacted tomato (Solanum lycopersicum) defenses against the chewing insect beet armyworm (Spodoptera exigua; BAW). In response to insect feeding, C. pentagona-infested (parasitized) tomato plants produced only one-third of the antiherbivore phytohormone jasmonic acid (JA) produced by unparasitized plants. Similarly, parasitized tomato, in contrast to unparasitized plants, failed to emit herbivore-induced volatiles after 3 d of BAW feeding. Although parasitism impaired antiherbivore defenses, BAW growth was slower on parasitized tomato leaves. Vines of C. pentagona did not translocate JA from BAW-infested plants: amounts of JA in parasite vines grown on caterpillar-fed and control plants were similar. Parasitized plants generally contained more salicylic acid (SA), which can inhibit JA in some systems. Parasitized mutant (NahG) tomato plants deficient in SA produced more JA in response to insect feeding than parasitized wild-type plants, further suggesting cross talk between the SA and JA defense signaling pathways. However, JA induction by BAW was still reduced in parasitized compared to unparasitized NahG, implying that other factors must be involved. We found that parasitized plants were capable of producing induced volatiles when experimentally treated with JA, indicating that resource depletion by the parasite does not fully explain the observed attenuation of volatile response to herbivore feeding. Collectively, these findings show that parasitic plants can have important consequences for host plant defense against herbivores.

Toxoplasma gondii in small neotropical wild felids

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William Alberto Cañon-Franco

2013-02-01

Full Text Available In the last decade, studies on wildlife worldwide have discovered key epidemiological aspects of the sylvatic cycle of Toxoplasma gondii. However, despite the known role of wild felines as definitive hosts in the transmission and maintenance of this parasite, few studies have focused on the involvement of these animals. Brazil exhibits the largest number of wild felid species in the Americas, all of which have a critical conservation status. However, serological detections, epidemiological studies and some molecular characterizations of T. gondii have primarily used Neotropical felid populations that are maintained in captivity, which does not reflect the disease behavior in free-living conditions. A systematic review of the worldwide scientific literature was conducted focusing on toxoplasmosis in small Neotropical felids. This review covered a number of aspects, including the state of scientific research, parasite transmission in the wild, the genetic characteristics of isolates, the relationship between these genetic characteristics and the pathogenicity of the parasite, and the risk factors linked to conflicts with humans. The present review shows the relevance of studying these felid populations based on their frequent interactions with humans in peri-urban areas and the need for further comprehensive studies to establish the real significance of T. gondii in public and animal health in tropical and temperate regions.

Pathological Roles of Wild-Type Cu, Zn-Superoxide Dismutase in Amyotrophic Lateral Sclerosis

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Yoshiaki Furukawa

2012-01-01

Full Text Available Dominant mutations in a Cu, Zn-superoxide dismutase (SOD1 gene cause a familial form of amyotrophic lateral sclerosis (ALS. While it remains controversial how SOD1 mutations lead to onset and progression of the disease, many in vitro and in vivo studies have supported a gain-of-toxicity mechanism where pathogenic mutations contribute to destabilizing a native structure of SOD1 and thus facilitate misfolding and aggregation. Indeed, abnormal accumulation of SOD1-positive inclusions in spinal motor neurons is a pathological hallmark in SOD1-related familial ALS. Furthermore, similarities in clinical phenotypes and neuropathology of ALS cases with and without mutations in sod1 gene have implied a disease mechanism involving SOD1 common to all ALS cases. Although pathogenic roles of wild-type SOD1 in sporadic ALS remain controversial, recent developments of novel SOD1 antibodies have made it possible to characterize wild-type SOD1 under pathological conditions of ALS. Here, I have briefly reviewed recent progress on biochemical and immunohistochemical characterization of wild-type SOD1 in sporadic ALS cases and discussed possible involvement of wild-type SOD1 in a pathomechanism of ALS.

Bacterial and parasitic diseases of parrots.

Science.gov (United States)

Doneley, Robert J T

2009-09-01

As wild-caught birds become increasingly rare in aviculture, there is a corresponding decline in the incidence of bacterial and parasitic problems and an increase in the recognition of the importance of maintaining health through better nutrition and husbandry. Nevertheless, the relatively close confines of captivity mean an increased pathogen load in the environment in which companion and aviary parrots live. This increased pathogen load leads to greater exposure of these birds to bacteria and parasites, and consequently a greater risk of infection and disease. This article discusses bacterial and parasitic infections in companion and aviary parrots. It includes the origins, pathogens, diagnosis, treatment, and some of the associated risk factors.

A Ten-Week Biochemistry Lab Project Studying Wild-Type and Mutant Bacterial Alkaline Phosphatase

Science.gov (United States)

Witherow, D. Scott

2016-01-01

This work describes a 10-week laboratory project studying wild-type and mutant bacterial alkaline phosphatase, in which students purify, quantitate, and perform kinetic assays on wild-type and selected mutants of the enzyme. Students also perform plasmid DNA purification, digestion, and gel analysis. In addition to simply learning important…

Differential induction of Toll-like receptors & type 1 interferons by Sabin attenuated & wild type 1 polioviruses in human neuronal cells.

Science.gov (United States)

Mohanty, Madhu C; Deshpande, Jagadish M

2013-01-01

Polioviruses are the causative agent of paralytic poliomyelitis. Attenuated polioviruses (Sabin oral poliovirus vaccine strains) do not replicate efficiently in neurons as compared to the wild type polioviruses and therefore do not cause disease. This study was aimed to investigate the differential host immune response to wild type 1 poliovirus (wild PV) and Sabin attenuated type 1 poliovirus (Sabin PV) in cultured human neuronal cells. By using flow cytometry and real time PCR methods we examined host innate immune responses and compared the role of toll like receptors (TLRs) and cytoplasmic RNA helicases in cultured human neuronal cells (SK-N-SH) infected with Sabin PV and wild PV. Human neuronal cells expressed very low levels of TLRs constitutively. Sabin PV infection induced significantly higher expression of TLR3, TLR7 and melanoma differentiation-associated protein-5 (MDA-5) m-RNA in neuronal cells at the beginning of infection (up to 4 h) as compared to wild PV. Further, Sabin PV also induced the expression of interferon α/β at early time point of infection. The induced expression of IFN α/β gene by Sabin PV in neuronal cells could be suppressed by inhibiting TLR7. Neuronal cell innate immune response to Sabin and wild polioviruses differ significantly for TLR3, TLR7, MDA5 and type 1 interferons. Effects of TLR7 activation and interferon production and Sabin virus replication in neuronal cells need to be actively investigated in future studies.

Parasitism by Cuscuta pentagona Attenuates Host Plant Defenses against Insect Herbivores1

Science.gov (United States)

Runyon, Justin B.; Mescher, Mark C.; De Moraes, Consuelo M.

2008-01-01

Considerable research has examined plant responses to concurrent attack by herbivores and pathogens, but the effects of attack by parasitic plants, another important class of plant-feeding organisms, on plant defenses against other enemies has not been explored. We investigated how attack by the parasitic plant Cuscuta pentagona impacted tomato (Solanum lycopersicum) defenses against the chewing insect beet armyworm (Spodoptera exigua; BAW). In response to insect feeding, C. pentagona-infested (parasitized) tomato plants produced only one-third of the antiherbivore phytohormone jasmonic acid (JA) produced by unparasitized plants. Similarly, parasitized tomato, in contrast to unparasitized plants, failed to emit herbivore-induced volatiles after 3 d of BAW feeding. Although parasitism impaired antiherbivore defenses, BAW growth was slower on parasitized tomato leaves. Vines of C. pentagona did not translocate JA from BAW-infested plants: amounts of JA in parasite vines grown on caterpillar-fed and control plants were similar. Parasitized plants generally contained more salicylic acid (SA), which can inhibit JA in some systems. Parasitized mutant (NahG) tomato plants deficient in SA produced more JA in response to insect feeding than parasitized wild-type plants, further suggesting cross talk between the SA and JA defense signaling pathways. However, JA induction by BAW was still reduced in parasitized compared to unparasitized NahG, implying that other factors must be involved. We found that parasitized plants were capable of producing induced volatiles when experimentally treated with JA, indicating that resource depletion by the parasite does not fully explain the observed attenuation of volatile response to herbivore feeding. Collectively, these findings show that parasitic plants can have important consequences for host plant defense against herbivores. PMID:18165323

Blood parasites of penguins: a critical review.

Science.gov (United States)

Vanstreels, Ralph Eric Thijl; Braga, Érika Martins; Catão-Dias, José Luiz

2016-07-01

Blood parasites are considered some of the most significant pathogens for the conservation of penguins, due to the considerable morbidity and mortality they have been shown to produce in captive and wild populations of these birds. Parasites known to occur in the blood of penguins include haemosporidian protozoans (Plasmodium, Leucocytozoon, Haemoproteus), piroplamid protozoans (Babesia), kinetoplastid protozoans (Trypanosoma), spirochete bacteria (Borrelia) and nematode microfilariae. This review provides a critical and comprehensive assessment of the current knowledge on these parasites, providing an overview of their biology, host and geographic distribution, epidemiology, pathology and implications for public health and conservation.

Genome-wide analysis of wild-type Epstein-Barr virus genomes derived from healthy individuals of the 1,000 Genomes Project.

Science.gov (United States)

Santpere, Gabriel; Darre, Fleur; Blanco, Soledad; Alcami, Antonio; Villoslada, Pablo; Mar Albà, M; Navarro, Arcadi

2014-04-01

Most people in the world (∼90%) are infected by the Epstein-Barr virus (EBV), which establishes itself permanently in B cells. Infection by EBV is related to a number of diseases including infectious mononucleosis, multiple sclerosis, and different types of cancer. So far, only seven complete EBV strains have been described, all of them coming from donors presenting EBV-related diseases. To perform a detailed comparative genomic analysis of EBV including, for the first time, EBV strains derived from healthy individuals, we reconstructed EBV sequences infecting lymphoblastoid cell lines (LCLs) from the 1000 Genomes Project. As strain B95-8 was used to transform B cells to obtain LCLs, it is always present, but a specific deletion in its genome sets it apart from natural EBV strains. After studying hundreds of individuals, we determined the presence of natural EBV in at least 10 of them and obtained a set of variants specific to wild-type EBV. By mapping the natural EBV reads into the EBV reference genome (NC007605), we constructed nearly complete wild-type viral genomes from three individuals. Adding them to the five disease-derived EBV genomic sequences available in the literature, we performed an in-depth comparative genomic analysis. We found that latency genes harbor more nucleotide diversity than lytic genes and that six out of nine latency-related genes, as well as other genes involved in viral attachment and entry into host cells, packaging, and the capsid, present the molecular signature of accelerated protein evolution rates, suggesting rapid host-parasite coevolution.

Helminth parasites of wild boar, Sus scrofa, in Iran.

Science.gov (United States)

Eslami, A; Farsad-Hamdi, S

1992-04-01

Fifty-seven wild boars (Sus scrofa) from protected regions of Iran were examined for helminths. Sixteen species of helminths were collected; there were ten nematodes, one acanthocephalan, two trematodes and three larval cestodes. New host and distribution records were established for all helminths except of Taenia solium cysticerci. Wild boar shared nine of these helminths with domestic pigs, six with ruminants and three with human beings in Iran. Metastrongylus pudendotectus and M. salmi are reported for the first time from Iran.

Chewing Lice of Swan Geese (Anser cygnoides): New Host-Parasite Associations

DEFF Research Database (Denmark)

Choi, Chang-Yong; Takekawa, John Y.; Prosser, Diann J.

2016-01-01

Chewing lice (Phthiraptera) that parasitize the globally threatened swan goose Anser cygnoides have been long recognized since the early 19th century, but those records were probably biased towards sampling of captive or domestic geese due to the small population size and limited distribution...... of its wild hosts. To better understand the lice species parasitizing swan geese that are endemic to East Asia, we collected chewing lice from 14 wild geese caught at 3 lakes in northeastern Mongolia. The lice were morphologically identified as 16 Trinoton anserinum (Fabricius, 1805), 11 Ornithobius...

Differential induction of Toll-like receptors & type 1 interferons by Sabin attenuated & wild type 1 polioviruses in human neuronal cells

Directory of Open Access Journals (Sweden)

Madhu C Mohanty

2013-01-01

Full Text Available Background & objectives: Polioviruses are the causative agent of paralytic poliomyelitis. Attenuated polioviruses (Sabin oral poliovirus vaccine strains do not replicate efficiently in neurons as compared to the wild type polioviruses and therefore do not cause disease. This study was aimed to investigate the differential host immune response to wild type 1 poliovirus (wild PV and Sabin attenuated type 1 poliovirus (Sabin PV in cultured human neuronal cells. Methods: By using flow cytometry and real time PCR methods we examined host innate immune responses and compared the role of toll like receptors (TLRs and cytoplasmic RNA helicases in cultured human neuronal cells (SK-N-SH infected with Sabin PV and wild PV. Results: Human neuronal cells expressed very low levels of TLRs constitutively. Sabin PV infection induced significantly higher expression of TLR3, TLR7 and melanoma differentiation-associated protein-5 (MDA-5 m-RNA in neuronal cells at the beginning of infection (up to 4 h as compared to wild PV. Further, Sabin PV also induced the expression of interferon α/β at early time point of infection. The induced expression of IFN α/β gene by Sabin PV in neuronal cells could be suppressed by inhibiting TLR7. Interpretation & conclusions: Neuronal cell innate immune response to Sabin and wild polioviruses differ significantly for TLR3, TLR7, MDA5 and type 1 interferons. Effects of TLR7 activation and interferon production and Sabin virus replication in neuronal cells need to be actively investigated in future studies.

Environmental and individual determinants of parasite richness across seasons in a free-ranging population of Mandrills (Mandrillus sphinx).

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Poirotte, Clémence; Basset, Didier; Willaume, Eric; Makaba, Fred; Kappeler, Peter M; Charpentier, Marie J E

2016-03-01

Parasites are ubiquitous and evolve fast. Therefore, they represent major selective forces acting on their hosts by influencing many aspects of their biology. Humans are no exception, as they share many parasites with animals and some of the most important outbreaks come from primates. While it appears important to understand the factors involved in parasite dynamics, we still lack a clear understanding of the determinants underlying parasitism. In this 2-year study, we identified several factors that influence parasite patterns in a wild population of free-ranging mandrills (Mandrillus sphinx). We explored the potential impact of seasonal factors-rainfall and temperature-and host characteristics, including sex, age, rank, and reproductive status, on parasite richness. We analyzed 12 parasite taxa found in 870 fecal samples collected from 63 individuals. Because nematodes and protozoa have different life-cycles, we analyzed these two types of parasites separately. Contrary to other studies where humid conditions seem favorable to parasite development, we report here that rainfall and high temperatures were associated with lower nematode richness and were not associated with lower protozoa richness. In contrast, female reproductive status seemed to reflect the seasonal patterns found for protozoa richness, as early gestating females harbored more protozoa than other females. Sex and dominance rank had no impact on overall parasite richness. However, age was associated with a specific decrease in nematode richness. Our study emphasizes the need to consider the ecological context, such as climatic conditions and habitat type, as well as the biology of both parasite and host when analyzing determinants of parasite richness. © 2015 Wiley Periodicals, Inc.

Pharmacologic Treatment Assigned for Niemann Pick Type C1 Disease Partly Changes Behavioral Traits in Wild-Type Mice.

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Schlegel, Victoria; Thieme, Markus; Holzmann, Carsten; Witt, Martin; Grittner, Ulrike; Rolfs, Arndt; Wree, Andreas

2016-11-09

Niemann-Pick Type C1 (NPC1) is an autosomal recessive inherited disorder characterized by accumulation of cholesterol and glycosphingolipids. Previously, we demonstrated that BALB/c-npc1 nih Npc1 -/- mice treated with miglustat, cyclodextrin and allopregnanolone generally performed better than untreated Npc1 -/- animals. Unexpectedly, they also seemed to accomplish motor tests better than their sham-treated wild-type littermates. However, combination-treated mutant mice displayed worse cognition performance compared to sham-treated ones. To evaluate effects of these drugs in healthy BALB/c mice, we here analyzed pharmacologic effects on motor and cognitive behavior of wild-type mice. For combination treatment mice were injected with allopregnanolone/cyclodextrin weekly, starting at P7. Miglustat injections were performed daily from P10 till P23. Starting at P23, miglustat was embedded in the chow. Other mice were treated with miglustat only, or sham-treated. The battery of behavioral tests consisted of accelerod, Morris water maze, elevated plus maze, open field and hot-plate tests. Motor capabilities and spontaneous motor behavior were unaltered in both drug-treated groups. Miglustat-treated wild-type mice displayed impaired spatial learning compared to sham- and combination-treated mice. Both combination- and miglustat-treated mice showed enhanced anxiety in the elevated plus maze compared to sham-treated mice. Additionally, combination treatment as well as miglustat alone significantly reduced brain weight, whereas only combination treatment reduced body weight significantly. Our results suggest that allopregnanolone/cyclodextrin ameliorate most side effects of miglustat in wild-type mice.

Pharmacologic Treatment Assigned for Niemann Pick Type C1 Disease Partly Changes Behavioral Traits in Wild-Type Mice

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Victoria Schlegel

2016-11-01

Full Text Available Niemann-Pick Type C1 (NPC1 is an autosomal recessive inherited disorder characterized by accumulation of cholesterol and glycosphingolipids. Previously, we demonstrated that BALB/c-npc1nihNpc1−/− mice treated with miglustat, cyclodextrin and allopregnanolone generally performed better than untreated Npc1−/− animals. Unexpectedly, they also seemed to accomplish motor tests better than their sham-treated wild-type littermates. However, combination-treated mutant mice displayed worse cognition performance compared to sham-treated ones. To evaluate effects of these drugs in healthy BALB/c mice, we here analyzed pharmacologic effects on motor and cognitive behavior of wild-type mice. For combination treatment mice were injected with allopregnanolone/cyclodextrin weekly, starting at P7. Miglustat injections were performed daily from P10 till P23. Starting at P23, miglustat was embedded in the chow. Other mice were treated with miglustat only, or sham-treated. The battery of behavioral tests consisted of accelerod, Morris water maze, elevated plus maze, open field and hot-plate tests. Motor capabilities and spontaneous motor behavior were unaltered in both drug-treated groups. Miglustat-treated wild-type mice displayed impaired spatial learning compared to sham- and combination-treated mice. Both combination- and miglustat-treated mice showed enhanced anxiety in the elevated plus maze compared to sham-treated mice. Additionally, combination treatment as well as miglustat alone significantly reduced brain weight, whereas only combination treatment reduced body weight significantly. Our results suggest that allopregnanolone/cyclodextrin ameliorate most side effects of miglustat in wild-type mice.

Parasites contribute to ecologically dependent postmating isolation in the adaptive radiation of three-spined stickleback.

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El Nagar, Aliya; MacColl, Andrew D C

2016-08-17

Spatial variation in parasitic infections is common, and has the potential to drive population divergence and the reproductive isolation of hosts. However, despite support from theory and model laboratory systems, little strong evidence has been forthcoming from the wild. Here, we show that parasites are likely to cause reproductive isolation in the adaptive radiation of three-spined stickleback. Adjacent wild populations on the Scottish island of North Uist differ greatly and consistently in the occurrence of different parasites that have substantial effects on fitness. Laboratory-reared fish are more resistant to experimental infection by parasite species from their own population. Furthermore, hybrid backcrosses between the host populations are more resistant to parasites from the parental population to which they are more closely related. These patterns provide strong evidence that parasites can cause ecological speciation, by contributing to selection against migrants and ecologically dependent postmating isolation. © 2016 The Author(s).

Wild type measles virus attenuation independent of type I IFN

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Horvat Branka

2008-02-01

Full Text Available Abstract Background Measles virus attenuation has been historically performed by adaptation to cell culture. The current dogma is that attenuated virus strains induce more type I IFN and are more resistant to IFN-induced protection than wild type (wt. Results The adaptation of a measles virus isolate (G954-PBL by 13 passages in Vero cells induced a strong attenuation of this strain in vivo. The adapted virus (G954-V13 differs from its parental strain by only 5 amino acids (4 in P/V/C and 1 in the M gene. While a vaccine strain, Edmonston Zagreb, could replicate equally well in various primate cells, both G954 strains exhibited restriction to the specific cell type used initially for their propagation. Surprisingly, we observed that both G954 strains induced type I IFN, the wt strain inducing even more than the attenuated ones, particularly in human plasmacytoid Dendritic Cells. Type I IFN-induced protection from the infection of both G954 strains depended on the cell type analyzed, being less efficient in the cells used to grow the viral strain. Conclusion Thus, mutations in M and P/V/C proteins can critically affect MV pathogenicity, cellular tropism and lead to virus attenuation without interfering with the α/β IFN system.

Flow cytometry-assisted rapid isolation of recombinant Plasmodium berghei parasites exemplified by functional analysis of aquaglyceroporin

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Kenthirapalan, Sanketha; Waters, Andrew P.; Matuschewski, Kai; Kooij, Taco W.A.

2012-01-01

The most critical bottleneck in the generation of recombinant Plasmodium berghei parasites is the mandatory in vivo cloning step following successful genetic manipulation. This study describes a new technique for rapid selection of recombinant P. berghei parasites. The method is based on flow cytometry to isolate isogenic parasite lines and represents a major advance for the field, in that it will speed the generation of recombinant parasites as well as cut down on animal use significantly. High expression of GFP during blood infection, a prerequisite for robust separation of transgenic lines by flow cytometry, was achieved. Isogenic recombinant parasite populations were isolated even in the presence of a 100-fold excess of wild-type (WT) parasites. Aquaglyceroporin (AQP) loss-of-function mutants and parasites expressing a tagged AQP were generated to validate this approach. aqp− parasites grow normally within the WT phenotypic range during blood infection of NMRI mice. Similarly, colonization of the insect vector and establishment of an infection after mosquito transmission were unaffected, indicating that AQP is dispensable for life cycle progression in vivo under physiological conditions, refuting its use as a suitable drug target. Tagged AQP localized to perinuclear structures and not the parasite plasma membrane. We suggest that flow-cytometric isolation of isogenic parasites overcomes the major roadblock towards a genome-scale repository of mutant and transgenic malaria parasite lines. PMID:23137753

Identification of a secreted casein kinase 1 in Leishmania donovani: effect of protein over expression on parasite growth and virulence.

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Mary Dan-Goor

Full Text Available Casein kinase 1 (CK1 plays an important role in eukaryotic signaling pathways, and their substrates include key regulatory proteins involved in cell differentiation, proliferation and chromosome segregation. The Leishmania genome encodes six potential CK1 isoforms, of which five have orthologs in other trypanosomatidae. Leishmania donovani CK1 isoform 4 (Ldck1.4, orthologous to LmjF27.1780 is unique to Leishmania and contains a putative secretion signal peptide. The full-length gene and three shorter constructs were cloned and expressed in E. coli as His-tag proteins. Only the full-length 62.3 kDa protein showed protein kinase activity indicating that the N-terminal and C-terminal domains are essential for protein activity. LdCK1.4-FLAG was stably over expressed in L. donovani, and shown by immunofluorescence to be localized primarily in the cytosol. Western blotting using anti-FLAG and anti-CK1.4 antibodies showed that this CK1 isoform is expressed and secreted by promastigotes. Over expression of LdCK1.4 had a significant effect on promastigote growth in culture with these parasites growing to higher cell densities than the control parasites (wild-type or Ld:luciferase, P<0.001. Analysis by flow cytometry showed a higher percentage, ∼4-5-fold, of virulent metacyclic promastigotes on day 3 among the LdCK1.4 parasites. Finally, parasites over expressing LdCK1.4 gave significantly higher infections of mouse peritoneal macrophages compared to wild-type parasites, 28.6% versus 6.3%, respectively (p = 0.0005. These results suggest that LdCK1.4 plays an important role in parasite survival and virulence. Further studies are needed to validate CK1.4 as a therapeutic target in Leishmania.

How does supplementary feeding affect endoparasite infection in wild boar?

DEFF Research Database (Denmark)

Oja, Ragne; Velstrom, Kaisa; Moks, Epp

2017-01-01

was associated with both wild boar and feeding site density, whereas the presence of Eimeria sp. oocysts in faecal samples was only associated with wild boar density. Helminth eggs were found more often from the soil of active and abandoned feeding sites than from control areas. This could reflect parasitic...

Genetic relationships and epidemiological links between wild type 1 poliovirus isolates in Pakistan and Afghanistan.

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Angez, Mehar; Shaukat, Shahzad; Alam, Muhammad M; Sharif, Salmaan; Khurshid, Adnan; Zaidi, Syed Sohail Zahoor

2012-02-22

Efforts have been made to eliminate wild poliovirus transmission since 1988 when the World Health Organization began its global eradication campaign. Since then, the incidence of polio has decreased significantly. However, serotype 1 and serotype 3 still circulate endemically in Pakistan and Afghanistan. Both countries constitute a single epidemiologic block representing one of the three remaining major global reservoirs of poliovirus transmission. In this study we used genetic sequence data to investigate transmission links among viruses from diverse locations during 2005-2007. In order to find the origins and routes of wild type 1 poliovirus circulation, polioviruses were isolated from faecal samples of Acute Flaccid Paralysis (AFP) patients. We used viral cultures, two intratypic differentiation methods PCR, ELISA to characterize as vaccine or wild type 1 and nucleic acid sequencing of entire VP1 region of poliovirus genome to determine the genetic relatedness. One hundred eleven wild type 1 poliovirus isolates were subjected to nucleotide sequencing for genetic variation study. Considering the 15% divergence of the sequences from Sabin 1, Phylogenetic analysis by MEGA software revealed that active inter and intra country transmission of many genetically distinct strains of wild poliovirus type 1 belonged to genotype SOAS which is indigenous in this region. By grouping wild type 1 polioviruses according to nucleotide sequence homology, three distinct clusters A, B and C were obtained with multiple chains of transmission together with some silent circulations represented by orphan lineages. Our results emphasize that there was a persistent transmission of wild type 1 polioviruses in Pakistan and Afghanistan during 2005-2007. The epidemiologic information provided by the sequence data can contribute to the formulation of better strategies for poliomyelitis control to those critical areas, associated with high risk population groups which include migrants

Genetic relationships and epidemiological links between wild type 1 poliovirus isolates in Pakistan and Afghanistan

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Angez Mehar

2012-02-01

Full Text Available Abstract Background/Aim Efforts have been made to eliminate wild poliovirus transmission since 1988 when the World Health Organization began its global eradication campaign. Since then, the incidence of polio has decreased significantly. However, serotype 1 and serotype 3 still circulate endemically in Pakistan and Afghanistan. Both countries constitute a single epidemiologic block representing one of the three remaining major global reservoirs of poliovirus transmission. In this study we used genetic sequence data to investigate transmission links among viruses from diverse locations during 2005-2007. Methods In order to find the origins and routes of wild type 1 poliovirus circulation, polioviruses were isolated from faecal samples of Acute Flaccid Paralysis (AFP patients. We used viral cultures, two intratypic differentiation methods PCR, ELISA to characterize as vaccine or wild type 1 and nucleic acid sequencing of entire VP1 region of poliovirus genome to determine the genetic relatedness. Results One hundred eleven wild type 1 poliovirus isolates were subjected to nucleotide sequencing for genetic variation study. Considering the 15% divergence of the sequences from Sabin 1, Phylogenetic analysis by MEGA software revealed that active inter and intra country transmission of many genetically distinct strains of wild poliovirus type 1 belonged to genotype SOAS which is indigenous in this region. By grouping wild type 1 polioviruses according to nucleotide sequence homology, three distinct clusters A, B and C were obtained with multiple chains of transmission together with some silent circulations represented by orphan lineages. Conclusion Our results emphasize that there was a persistent transmission of wild type1 polioviruses in Pakistan and Afghanistan during 2005-2007. The epidemiologic information provided by the sequence data can contribute to the formulation of better strategies for poliomyelitis control to those critical areas

Parasites as prey

NARCIS (Netherlands)

Goedknegt, M.A.; Welsh, J.E.; Thieltges, D.W.

2012-01-01

Parasites are usually considered to use their hosts as a resource for energy. However, there is increasing awareness that parasites can also become a resource themselves and serve as prey for other organisms. Here we describe various types of predation in which parasites act as prey for other

Sex as a strategy against rapidly evolving parasites.

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Auld, Stuart K J R; Tinkler, Shona K; Tinsley, Matthew C

2016-12-28

Why is sex ubiquitous when asexual reproduction is much less costly? Sex disrupts coadapted gene complexes; it also causes costs associated with mate finding and the production of males who do not themselves bear offspring. Theory predicts parasites select for host sex, because genetically variable offspring can escape infection from parasites adapted to infect the previous generations. We examine this using a facultative sexual crustacean, Daphnia magna, and its sterilizing bacterial parasite, Pasteuria ramosa We obtained sexually and asexually produced offspring from wild-caught hosts and exposed them to contemporary parasites or parasites isolated from the same population one year later. We found rapid parasite adaptation to replicate within asexual but not sexual offspring. Moreover, sexually produced offspring were twice as resistant to infection as asexuals when exposed to parasites that had coevolved alongside their parents (i.e. the year two parasite). This fulfils the requirement that the benefits of sex must be both large and rapid for sex to be favoured by selection. © 2016 The Author(s).

Diversity of parasites in wild Astronotus ocellatus (Perciformes, Cichlidae), an ornamental and food fish in Brazil.

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Tavares-Dias, Marcos; Neves, Ligia R

2017-01-01

The community composition of parasites was characterized in Astronotus ocellatus from a tributary of the Amazon River, northern Brazil. The prevalence was 87.9%, and a total of 526,052 parasites were collected, with a mean of 15,941 parasites per host. Nine taxa of ecto- and endo-parasites were identified, but Ichthyophthirius multifiliis was the dominant species, while Piscinoodinium pillulare, Clinostomum marginatum and Argulus multicolor were the least prevalent parasites. The parasite community was characterized by a low species richness, low diversity and low evenness. Host body size was not found to influence the composition of the parasite community, and there was no significant correlation between abundance of any parasite species and host body size. Papers published concerning the presence of parasites in this host in different hydrographic basins within Brazil indicate that 22 species of parasites are known to infect A. ocellatus, including species of ectoparasites and endoparasites. In Brazil, ectoparasites species, particularly crustaceans, have been found to parasitize A. ocellatus in relatively high numbers. This predominance of ectoparasites is typical of fish of lentic ecosystems. Finally, the presence of different endoparasites taxa suggest that A. ocellatus acts as an intermediate or definitive host.

Molecular detection of Hepatozoon spp. in Brazilian and exotic wild carnivores.

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André, M R; Adania, C H; Teixeira, R H F; Vargas, G H; Falcade, M; Sousa, L; Salles, A R; Allegretti, S M; Felippe, P A N; Machado, R Z

2010-10-11

Hepatozoon spp. are apicomplexan parasites that infect a wide variety of animals. The infection occurs through the ingestion of a hematophagous arthropod definitive host. Herein, we assessed the presence of Hepatozoon spp. in 165 captive wild felids and 100 captive wild canids using molecular techniques. We found that 6 felids (4 little spotted cats, 1 jaguarondi, and 1 puma) and 5 canids (2 bush dogs, 1 fox, 1 crab-eating fox, and 1 maned wolf) were positive for Hepatozoon spp. Hepatozoon spp. may be a potential pathogen and an opportunistic parasite in immunocompromised animals or if occurring in concomitant infections. Because most Brazilian wild felids and canids are endangered, knowing whether Hepatozoon infection represents a threat for these animals is crucial. Copyright 2010 Elsevier B.V. All rights reserved.

Rearing in seawater mesocosms improves the spawning performance of growth hormone transgenic and wild-type coho salmon.

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Rosalind A Leggatt

Full Text Available Growth hormone (GH transgenes can significantly accelerate growth rates in fish and cause associated alterations to their physiology and behaviour. Concern exists regarding potential environmental risks of GH transgenic fish, should they enter natural ecosystems. In particular, whether they can reproduce and generate viable offspring under natural conditions is poorly understood. In previous studies, GH transgenic salmon grown under contained culture conditions had lower spawning behaviour and reproductive success relative to wild-type fish reared in nature. However, wild-type salmon cultured in equal conditions also had limited reproductive success. As such, whether decreased reproductive success of GH transgenic salmon is due to the action of the transgene or to secondary effects of culture (or a combination has not been fully ascertained. Hence, salmon were reared in large (350,000 L, semi-natural, seawater tanks (termed mesocosms designed to minimize effects of standard laboratory culture conditions, and the reproductive success of wild-type and GH transgenic coho salmon from mesocosms were compared with that of wild-type fish from nature. Mesocosm rearing partially restored spawning behaviour and success of wild-type fish relative to culture rearing, but remained lower overall than those reared in nature. GH transgenic salmon reared in the mesocosm had similar spawning behaviour and success as wild-type fish reared in the mesocosm when in full competition and without competition, but had lower success in male-only competition experiments. There was evidence of genotype×environmental interactions on spawning success, so that spawning success of transgenic fish, should they escape to natural systems in early life, cannot be predicted with low uncertainty. Under the present conditions, we found no evidence to support enhanced mating capabilities of GH transgenic coho salmon compared to wild-type salmon. However, it is clear that GH transgenic

First report of a Mephitidae (Mammalia: Carnivora) naturally infected by parasites of the genus Physaloptera (Rudolphi, 1918) (Spirurida: Physalopteridae)

OpenAIRE

Gregório Correa Guimarães; Thales Augusto Barçante; Pedro Soares Bezerra-Junior; Amanda do Nascimento Oliveira; Matheus Camargo de Britto Rosa; Gabriela Castro Lopes; Joziana Muniz de Paiva Barçante

2015-01-01

Wild animals may be regarded as reservoirs of several parasite species. The occurrence of certain parasitic agents may provide significant information on host’s ecology and behavior and its trophic relations. Thus, this study aimed to determine the parasitic fauna of wild animals from southern Minas Gerais within the period from January to December 2011. A cross-sectional study was conducted with a convenience sample consisting of the dead bodies of two run over animals, which were rescued fr...

Glutathione-deficient Plasmodium berghei parasites exhibit growth delay and nuclear DNA damage.

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Padín-Irizarry, Vivian; Colón-Lorenzo, Emilee E; Vega-Rodríguez, Joel; Castro, María Del R; González-Méndez, Ricardo; Ayala-Peña, Sylvette; Serrano, Adelfa E

2016-06-01

Plasmodium parasites are exposed to endogenous and exogenous oxidative stress during their complex life cycle. To minimize oxidative damage, the parasites use glutathione (GSH) and thioredoxin (Trx) as primary antioxidants. We previously showed that disruption of the Plasmodium berghei gamma-glutamylcysteine synthetase (pbggcs-ko) or the glutathione reductase (pbgr-ko) genes resulted in a significant reduction of GSH in intraerythrocytic stages, and a defect in growth in the pbggcs-ko parasites. In this report, time course experiments of parasite intraerythrocytic development and morphological studies showed a growth delay during the ring to schizont progression. Morphological analysis shows a significant reduction in size (diameter) of trophozoites and schizonts with increased number of cytoplasmic vacuoles in the pbggcs-ko parasites in comparison to the wild type (WT). Furthermore, the pbggcs-ko mutants exhibited an impaired response to oxidative stress and increased levels of nuclear DNA (nDNA) damage. Reduced GSH levels did not result in mitochondrial DNA (mtDNA) damage or protein carbonylations in neither pbggcs-ko nor pbgr-ko parasites. In addition, the pbggcs-ko mutant parasites showed an increase in mRNA expression of genes involved in oxidative stress detoxification and DNA synthesis, suggesting a potential compensatory mechanism to allow for parasite proliferation. These results reveal that low GSH levels affect parasite development through the impairment of oxidative stress reduction systems and damage to the nDNA. Our studies provide new insights into the role of the GSH antioxidant system in the intraerythrocytic development of Plasmodium parasites, with potential translation into novel pharmacological interventions. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Diversity of parasites in wild Astronotus ocellatus (Perciformes, Cichlidae, an ornamental and food fish in Brazil

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MARCOS TAVARES-DIAS

2017-10-01

Full Text Available ABSTRACT The community composition of parasites was characterized in Astronotus ocellatus from a tributary of the Amazon River, northern Brazil. The prevalence was 87.9%, and a total of 526,052 parasites were collected, with a mean of 15,941 parasites per host. Nine taxa of ecto- and endo-parasites were identified, but Ichthyophthirius multifiliis was the dominant species, while Piscinoodinium pillulare, Clinostomum marginatum and Argulus multicolor were the least prevalent parasites. The parasite community was characterized by a low species richness, low diversity and low evenness. Host body size was not found to influence the composition of the parasite community, and there was no significant correlation between abundance of any parasite species and host body size. Papers published concerning the presence of parasites in this host in different hydrographic basins within Brazil indicate that 22 species of parasites are known to infect A. ocellatus, including species of ectoparasites and endoparasites. In Brazil, ectoparasites species, particularly crustaceans, have been found to parasitize A. ocellatus in relatively high numbers. This predominance of ectoparasites is typical of fish of lentic ecosystems. Finally, the presence of different endoparasites taxa suggest that A. ocellatus acts as an intermediate or definitive host.

Molecular characterization of Hepatozoon spp. infection in endangered Indian wild felids and canids.

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Pawar, Rahul Mohanchandra; Poornachandar, Anantula; Srinivas, Pasham; Rao, Kancharapu Ramachandra; Lakshmikantan, Uthandaraman; Shivaji, Sisinthy

2012-05-25

Hepatozoon species are parasites that infect a wide variety of domestic and wild animals. The objective of this study was to perform the molecular detection and characterization of Hepatozoon spp. in Asiatic lion, Indian tiger, Indian leopard, Indian wild dog, Indian domestic dog and cat based on partial 18S rRNA gene sequences from Hepatozoon spp. in the naturally infected animals. Hepatozoon spp. could be detected in blood samples of 5 out of 9 Asiatic lions, 2 out of 5 Indian tigers, 2 out of 4 Indian leopards and 2 out of 2 Indian wild dogs and, 2 out of 4 domestic cats and 2 out of 3 domestic dog samples by PCR. Sequencing of PCR amplicon and BLAST analysis of partial 18S rRNA gene sequences indicated that the Hepatozoon spp. in Asiatic lion, Bengal tiger, Indian leopard and domestic cat was Hepatozoon felis (98-99% similarity) and in the Indian wild and domestic dog the phylogenetic neighbour was Hepatozoon canis (97-100% similarity). Presence of H. felis and H. canis in both domestic and wild animals suggested that they are not host specific and the same parasite causes infection in domestic and wild felids and canids in India and from different parts of the world. To our knowledge, this is the first report on detection and molecular characterization of H. felis infection in Asiatic lions, Indian tigers, Indian leopards and H. canis in Indian wild dog. Hepatozoon spp. may be a potential pathogen and an opportunistic parasite in immuno-compromised animals and could thus represent a threat to endangered Indian wild felids and canids. Copyright © 2011 Elsevier B.V. All rights reserved.

The wild type as concept and in experimental practice: A history of its role in classical genetics and evolutionary theory.

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Holmes, Tarquin

2017-06-01

Wild types in genetics are specialised strains of laboratory experimental organism which principally serve as standards against which variation is measured. As selectively inbred lineages highly isolated from ancestral wild populations, there appears to be little wild or typical about them. I will nonetheless argue that they have historically been successfully used as stand-ins for nature, allowing knowledge produced in the laboratory to be extrapolated to the natural world. In this paper, I will explore the 19th century origins of the wild type concept, the theoretical and experimental innovations which allowed concepts and organisms to move from wild nature to laboratory domestication c. 1900 (resulting in the production of standardised lab strains), and the conflict among early geneticists between interactionist and atomist accounts of wild type, which would eventually lead to the conceptual disintegration of wild types and the triumph of genocentrism and population genetics. I conclude by discussing how the strategy of using wild type strains to represent nature in the lab has nonetheless survived the downfall of the wild type concept and continues to provide, significant limitations acknowledged, an epistemically productive means of investigating heredity and evolutionary variation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Prevalence of Toxoplasma gondii and potentially zoonotic helminths in wild boars (Sus scrofa hunted in central Italy

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Roberto Amerigo Papini

2018-03-01

Full Text Available Our aim was to evaluate the risk of human toxoplasmosis via meat consumption from wild boars by estimating the seroprevalence of Toxoplasma gondii in animals hunted in central Italy. Using a modified agglutination test, 213 sera from wild boars were examined for anti-Toxoplasma IgG antibodies. Diaphragm samples (n=65 from seropositive and seronegative animals were tested by nested-PCR to detect T. gondii DNA. Toxoplasma DNA from diaphragms was genotyped by PCR-RFLP using 12 genetic markers. Moreover, the aim of the study was also to identify helminth infections of wild boars in the selected area and to evaluate their hazard for humans. Examination of sera revealed a seroprevalence of 12.2%. Only one T. gondii strain could be genotyped from a seropositive animal and PCR-RFLP revealed that it belonged to type II. Analysis of 50 samples of faeces and 32 small intestines revealed that 78% and 15.6% of the samples harboured parasites, respectively, with the occurrence of parasites potentially dangerous for humans. These latter included Ascaris suum, Macracanthorhynchus hirudinaceus, Trichuris suis, and Metastrongylus spp. A significant association was found between coprological positivity and male sex. These results indicate that T. gondii infection may be present in wild boar tissues and consumption of undercooked or raw wild boar meat may expose humans to risk of toxoplasmosis in the study area. Furthermore, the study highlights that wild boars are hosts of helminths of veterinary and medical importance transmissible to pigs and humans.

Occurrence and seasonality of internal parasite infection in elephants, Loxodonta africana, in the Okavango Delta, Botswana.

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Baines, Lydia; Morgan, Eric R; Ofthile, Mphoeng; Evans, Kate

2015-04-01

It is known from studies in a wide range of wild and domestic animals, including elephants, that parasites can affect growth, reproduction and health. A total of 458 faecal samples from wild elephants were analysed using a combination of flotation and sedimentation methods. Coccidian oocysts (prevalence 51%), and nematode (77%) and trematode (24%) eggs were found. Species were not identified, though trematode egg morphology was consistent with that of the intestinal fluke Protofasciola robusta. The following factors were found to have a significant effect on parasite infection: month, year, sex, age, and group size and composition. There was some evidence of peak transmission of coccidia and nematodes during the rainy season, confirmed for coccidia in a parallel study of seven sympatric domesticated elephants over a three month period. Nematode eggs were more common in larger groups and nematode egg counts were significantly higher in elephants living in maternal groups (mean 1116 eggs per gram, standard deviation, sd 685) than in all-male groups (529, sd 468). Fluke egg prevalence increased with increasing elephant age. Preservation of samples in formalin progressively decreased the probability of detecting all types of parasite over a storage time of 1-15 months. Possible reasons for associations between other factors and infection levels are discussed.

Occurrence and seasonality of internal parasite infection in elephants, Loxodonta africana, in the Okavango Delta, Botswana

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Lydia Baines

2015-04-01

Full Text Available It is known from studies in a wide range of wild and domestic animals, including elephants, that parasites can affect growth, reproduction and health. A total of 458 faecal samples from wild elephants were analysed using a combination of flotation and sedimentation methods. Coccidian oocysts (prevalence 51%, and nematode (77% and trematode (24% eggs were found. Species were not identified, though trematode egg morphology was consistent with that of the intestinal fluke Protofasciola robusta. The following factors were found to have a significant effect on parasite infection: month, year, sex, age, and group size and composition. There was some evidence of peak transmission of coccidia and nematodes during the rainy season, confirmed for coccidia in a parallel study of seven sympatric domesticated elephants over a three month period. Nematode eggs were more common in larger groups and nematode egg counts were significantly higher in elephants living in maternal groups (mean 1116 eggs per gram, standard deviation, sd 685 than in all-male groups (529, sd 468. Fluke egg prevalence increased with increasing elephant age. Preservation of samples in formalin progressively decreased the probability of detecting all types of parasite over a storage time of 1–15 months. Possible reasons for associations between other factors and infection levels are discussed.

Fusarium spp. Associated with Field-Grown Grain of Near-Isogenic Low Lignin and Wild-Type Sorghum

Science.gov (United States)

Fusarium spp. associated with field-grown grain of near-isogenic low lignin and wild-type sorghum. Deanna Funnell-Harris and Jeff Pedersen, USDA-ARS, Lincoln, NE Previous studies indicated that low lignin brown midrib (bmr) sorghum may be more resistant to Fusarium spp. than wild-type and that phen...

Transplacental and oral transmission of wild-type bluetongue virus serotype 8 in cattle after experimental infection

NARCIS (Netherlands)

Backx, A.; Heutink, C.G.; Rooij, van E.M.A.; Rijn, van P.A.

2009-01-01

Potential vertical transmission of wild-type bluetongue virus serotype 8 (BTV-8) in cattle was explored in this experiment. We demonstrated transplacental transmission of wild-type BTV-8 in one calf and oral infection with BTV-8 in another calf. Following the experimental BTV-8 infection of seven

Parasites and cancers: parasite antigens as possible targets for cancer immunotherapy.

Science.gov (United States)

Darani, Hossein Yousofi; Yousefi, Morteza

2012-12-01

An adverse relationship between some parasite infections and cancer in the human population has been reported by different research groups. Anticancer activity of some parasites such as Trypanosoma cruzi, Toxoplasma gondii, Toxocara canis, Acantamoeba castellani and Plasmodium yoelii has been shown in experimental animals. Moreover, it has been shown that cancer-associated mucin-type O-glycan compositions are made by parasites, therefore cancers and parasites have common antigens. In this report anticancer activities of some parasites have been reviewed and the possible mechanisms of these actions have also been discussed.

Efficacy of parasitological diagnosis methods in wild animals kept in captivity

OpenAIRE

Carvalho, Aline Feola; Barnabe, Anderson Sena; Federsoni, Igor Popovic; Ferraz, Renato Ribeiro Nogueira; Marco, Rogerio Milton De; Garcia, Isabel Priscilla

2018-01-01

ABSTRACT: Parasitic diseases are common in wild animals kept in captivity, and the research of these parasites is a tool used in wildlife management actions. Once the method most used in the practice of veterinary laboratories is the direct examination, it was considered appropriate to report the parasitism in captivity wildlife comparing this technique with modified methods of Hoffman, Pons and Janer (HPJ) and Willis. Fresh feces were surveyed in eleven precincts with specimens of the class ...

DNA binding properties of dioxin receptors in wild-type and mutant mouse hepatoma cells

International Nuclear Information System (INIS)

Cuthill, S.; Poellinger, L.

1988-01-01

The current model of action of 2,3,7,8-tetrachlorodibenzo-p-dioxin (dioxin) entails stimulation of target gene transcription via the formation of dioxin-receptor complexes and subsequent accumulation of the complexes within the cell nucleus. Here, the authors have analyzed the DNA binding properties of the dioxin receptor in wild-type mouse hepatoma (Hepa 1c1c7) cells and a class of nonresponsive mutant cells which fail to accumulate dioxin-receptor complexes within the nucleus in vivo. In vitro, both the wild-type and mutant [ 3 H]dioxin-receptor complexes exhibited low affinity for DNA-cellulose (5-8% and around 4% retention, respectively) in the absence of prior biochemical manipulations. However, following chromatography on heparin-Sepharose, the wild-type but not the mutant dioxin receptor was transformed to a species with an increased affinity for DNA (40-50% retention on DNA-cellulose). The gross molecular structure of the mutant, non DNA binding dioxin receptor did not appear to be altered as compared to that of the wild-type receptor. These results imply that the primary deficiency in the mutant dioxin receptor form may reside at the DNA binding level and that, in analogy to steroid hormone receptors, DNA binding of the receptor may be an essential step in the regulation of target gene transcription by dioxin

The effect of UVB on flavonoid biosynthesis in wild type and mutant petunia and arabidopsis

International Nuclear Information System (INIS)

Ryan, K.G.; Swinny, E.E.; Markham, K.R.; Winefield, C.

2000-01-01

Full text: Flavonoids may protect plants against damage by UVB radiation. Flavonoid composition and mRNA expression were determined following growth of plants under natural light, and under natural light with low UVB and with enhanced UVB. In wild-type Arabidopsis and Petunia, UVB induced an increase in total levels of flavonols and this was due to an up-regulation of, several genes coding for key enzymes in the phenylpropanoid pathway. In addition, UVB induced a higher rate of production of the di-hydroxylated si flavonol, quercetin glycoside than of the mono-hydroxylated equivalent, of kaempferol glycoside. Thus the ratio of quercetin to kaempferol increased with UVB treatment in wild type plants, and this suggests that the flavonoid r 3'hydroxylase (F3'H) enzyme, which converts dihydrokaempferol to dihydroquercetin, may play a key role in plant protection from UVB. Mutant plants of both species lacking this F3'H gene were grown under similar UV conditions. Leaves of the mutant Arabidopsis plant (tt7) did not contain quercetin, even under the enhanced UVB treatment. Under the low UVB treatment the total amount of flavonol was similar to the wild-type (Ler), but with increasing UVB, total flavonol (i.e. kaempferol) levels were significantly higher than in similarly treated wild type plants. In the Petunia F3'H mutant, low levels of quercetin were found even in the low UVB treatment, which indicates this variety may be producing some quercetin via an alternative pathway. Under UVB radiation, total flavonoids increased to levels significantly higher than in similarly treated wild type plants, and most of this material was kaempferol. These observations suggest that quercetin is the preferred protective flavonol in wild type plants, due perhaps to enhanced antioxidant or free radical scavenging activity. In mutant plants lacking the F3'H enzyme, the response is to produce a larger amount of a less effective photoprotectant

Effects of regionally applied heating on the respiration of wild type ...

African Journals Online (AJOL)

Nocturnal dark respiration (Rn) in wild type and transgenic soybean plants ... Illinois, USA under ambient and elevated CO2 conditions was examined in this study. ... Experimental plants were transferred to a controlled growth chamber at V4 ...

Genotyping of Toxoplasma gondii and Sarcocystis spp. in road-killed wild mammals from the Central Western Region of the State of São Paulo, Brazil.

Science.gov (United States)

Richini-Pereira, Virgínia Bodelão; Marson, Pâmela Merlo; Silva, Rodrigo Costa da; Langoni, Helio

2016-01-01

Road-killed wild animals host zoonotic pathogens such as Toxoplasma gondii, offering a new opportunity for the epidemiological study of these infectious organisms. This investigation aimed to determine the presence of T. gondii and other apicomplexan parasites in tissue samples of 64 road-killed wild animals, using polymerase chain reaction (PCR). Positive samples were then typed by PCR-restriction fragment length polymorphism (RFLP) using 7 markers: SAG1, 5'-3'SAG2, SAG3, BTUB, c29-6, PK1, and Apico. PCR-RFLP targeting 18S ribosomal RNA (rRNA) genes was also performed on all samples to detect other apicomplexan parasites. T. gondii DNA was detected in 16 tissue samples from 8 individual animals, as follows: 1 Cerdocyon thous (crab-eating fox), 1 Didelphis albiventris (white-eared opossum), 1 Lutreolina crassicaudata (lutrine opossum), 2 Myrmecophaga tridactyla (giant anteater), 1 Procyon cancrivorus (crab-eating raccoon), and 2 Sphiggurus spinosus (Paraguay hairy dwarf porcupine). Seven different T. gondii genotypes were identified, 6 of which were novel. Typing by 18S rRNA verified these 16 T. gondii-infected samples, and identified 1 Sarcocystis spp.-infected animal [Dasypus novemcinctus (nine-banded armadillo)]. The amplified T. gondii (GenBank accession No. L37415.1) and Sarcocystis spp. 18S rRNA products were confirmed by sequencing. Our results indicate that T. gondii is commonly present in wild mammals, which act as sources of infection for humans and animals, including other wild species. The approach employed herein proved useful for detecting T. gondii and Sarcocystis spp. in the environment and identifying their natural reservoirs, contributing to our understanding of host-parasite interactions.

Genotyping of Toxoplasma gondii and Sarcocystis spp. in road-killed wild mammals from the Central Western Region of the State of São Paulo, Brazil

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Virgínia Bodelão Richini-Pereira

Full Text Available Abstract INTRODUCTION: Road-killed wild animals host zoonotic pathogens such as Toxoplasma gondii, offering a new opportunity for the epidemiological study of these infectious organisms. METHODS This investigation aimed to determine the presence of T. gondii and other apicomplexan parasites in tissue samples of 64 road-killed wild animals, using polymerase chain reaction (PCR. Positive samples were then typed by PCR-restriction fragment length polymorphism (RFLP using 7 markers: SAG1, 5′-3′SAG2, SAG3, BTUB, c29-6, PK1, and Apico. PCR-RFLP targeting 18S ribosomal RNA (rRNA genes was also performed on all samples to detect other apicomplexan parasites. RESULTS T. gondii DNA was detected in 16 tissue samples from 8 individual animals, as follows: 1 Cerdocyon thous (crab-eating fox, 1 Didelphis albiventris (white-eared opossum, 1 Lutreolina crassicaudata (lutrine opossum, 2 Myrmecophaga tridactyla (giant anteater, 1 Procyon cancrivorus (crab-eating raccoon, and 2 Sphiggurus spinosus (Paraguay hairy dwarf porcupine. Seven different T. gondii genotypes were identified, 6 of which were novel. Typing by 18S rRNA verified these 16 T. gondii-infected samples, and identified 1 Sarcocystis spp.-infected animal [Dasypus novemcinctus (nine-banded armadillo]. The amplified T. gondii (GenBank accession No. L37415.1 and Sarcocystis spp. 18S rRNA products were confirmed by sequencing. CONCLUSIONS Our results indicate that T. gondii is commonly present in wild mammals, which act as sources of infection for humans and animals, including other wild species. The approach employed herein proved useful for detecting T. gondii and Sarcocystis spp. in the environment and identifying their natural reservoirs, contributing to our understanding of host-parasite interactions.

Endoparasites of Wild Mammals Sheltered in Wildlife Hospitals and Rehabilitation Centres in Greece

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Theophanes K. Liatis

2017-12-01

Full Text Available Wildlife parasitic diseases represent an important field of investigation as they may have a significant impact on wild animals’ health and fitness, and may also have zoonotic implications. This study aimed to investigate the occurrence of endoparasites in wild mammals admitted to wildlife hospitals and rehabilitation centres in Greece. Sixty-five animals belonging to 17 species and originated from various areas of continental and insular Greece were included in the survey. The most numerous animal species examined were hedgehogs (n = 19, red foxes (n = 16, and European roe deer (n = 6. Faecal samples were collected individually and examined by floatation and sedimentation method. Parasites were found in 46 (70.7% of the animals. Most parasites found in canids, felids, and ruminants are of great relevance to the domestic animals’ health and some of them are also of zoonotic importance. To the best of the author’s knowledge, this is the first report of endoparasites in hedgehogs, roe deers, fallow deers, badgers, and bats, and the first report of the pulmonary nematode Troglostrongylus brevior in a wild cat in Greece. The significance of the parasites found in each animal species in regard to their health and their relevance to domestic animals and human health is discussed.

Interspecies Variation in the Susceptibility of a Wild-Derived Colony of Mice to Pinworms (Aspiculuris tetraptera).

Science.gov (United States)

Curtis, Ryan C; Murray, Jill K; Campbell, Polly; Nagamori, Yoko; Molnar, Adam; Jackson, Todd A

2017-01-01

Pinworms are common parasites in wild and laboratory rodents. Despite their relative nonpathogenicity in immunocompetent models, pinworm infections add an unwanted variable and may confound some types of research. For this reason, health monitoring programs and biosecurity measures aim to minimize the spread of pinworm infections into colonies free from the organisms. Wild-derived and laboratory strains of mice have shown varied susceptibility to infection with Aspiculuris tetraptera, the most commonly found murine pinworm. In particular, susceptibility is increased in wild-derived mice, young animals, and males. Routine surveillance at our institution revealed pinworm infection (A. tetraptera only) within a colony of multiple, wild-derived species of Mus, although only specific species showed positive results during initial sampling. To assess whether species-associated differences in susceptibility were present, we analyzed fecal egg counts of A. tetraptera in every cage of the colony. Our results revealed significant differences in susceptibility between various species and subspecies of Mus. Egg counts were significantly higher in Mus spicilegus than Mus m. domesticus (WSB/EiJ) and Mus macedonicus. Mus spretus had higher egg counts than M. m. domesticus (WSB/EiJ), M. m. musculus (PWK/PhJ), and M. macedonicus. Egg counts did not differ in regard to age, sex, or number of mice per cage. As wild-derived mouse models continue to compliment research largely based on laboratory strains, it will be important to understand host-parasite interactions and their effects on research, particularly studies evaluating immune responses, behavior, growth, and other physiologic parameters.

Comparative analysis of the protein compositions between wild type and body color mutant of helicoverpa armigera adult

International Nuclear Information System (INIS)

He Lihua; Chen Jin'e; Liu Yan; Wang Yongqiang; Liu Peigang; Meng Zhiqi

2012-01-01

To gain an in-depth understanding of the fineness and regulation mechanism of body color mutant of Helicoverpa armigera Hbner, the protein composition differences between adult of dominant mutant, recessive mutant and wild type were studied using the SDS-PAGE combined with MALDI-TOF-TOF/MS and bioinformatics analysis. The results indicated that the protein composition of the dominant mutant and wild type had little difference. However, there were obvious differences between the recessive mutant and wild-type. Three specific stripe were chosen for mass spectrometry and bioinformatics analysis, and two types of proteins related to energy metabolism and cytoskeleton were identified. These findings suggested that the two types of proteins may be associated with occurrence and regulation of body color mutant traits of H. armigera. (authors)

Cessation of a salmon decline with control of parasites

KAUST Repository

Peacock, Stephanie J.; Krkošek, Martin; Proboszcz, Stan; Orr, Craig; Lewis, Mark A.

2013-01-01

(Oncorhynchus gorbuscha) from Pacific Canada indicates that adaptive changes in parasite management on salmon farms have yielded positive conservation outcomes. After four years of sea lice epizootics and wild salmon population decline, parasiticide application

Wild-type MIC distributions for aminoglycoside and cyclic polypeptide antibiotics used for treatment of Mycobacterium tuberculosis infections.

Science.gov (United States)

Juréen, P; Angeby, K; Sturegård, E; Chryssanthou, E; Giske, C G; Werngren, J; Nordvall, M; Johansson, A; Kahlmeter, G; Hoffner, S; Schön, T

2010-05-01

The aminoglycosides and cyclic polypeptides are essential drugs in the treatment of multidrug-resistant tuberculosis, underscoring the need for accurate and reproducible drug susceptibility testing (DST). The epidemiological cutoff value (ECOFF) separating wild-type susceptible strains from non-wild-type strains is an important but rarely used tool for indicating susceptibility breakpoints against Mycobacterium tuberculosis. In this study, we established wild-type MIC distributions on Middlebrook 7H10 medium for amikacin, kanamycin, streptomycin, capreomycin, and viomycin using 90 consecutive clinical isolates and 21 resistant strains. Overall, the MIC variation between and within runs did not exceed +/-1 MIC dilution step, and validation of MIC values in Bactec 960 MGIT demonstrated good agreement. Tentative ECOFFs defining the wild type were established for all investigated drugs, including amikacin and viomycin, which currently lack susceptibility breakpoints for 7H10. Five out of seven amikacin- and kanamycin-resistant isolates were classified as susceptible to capreomycin according to the current critical concentration (10 mg/liter) but were non-wild type according to the ECOFF (4 mg/liter), suggesting that the critical concentration may be too high. All amikacin- and kanamycin-resistant isolates were clearly below the ECOFF for viomycin, and two of them were below the ECOFF for streptomycin, indicating that these two drugs may be considered for treatment of amikacin-resistant strains. Pharmacodynamic indices (peak serum concentration [Cmax]/MIC) were more favorable for amikacin and viomycin compared to kanamycin and capreomycin. In conclusion, our data emphasize the importance of establishing wild-type MIC distributions for improving the quality of drug susceptibility testing against Mycobacterium tuberculosis.

Chewing lice of swan geese (Anser cygnoides): New host-parasite associations

Science.gov (United States)

Choi, Chang-Yong; Takekawa, John Y.; Prosser, Diann J.; Smith, Lacy M.; Ely, Craig R.; Fox, Anthony D.; Cao, Lei; Wang, Xin; Batbayar, Nyambayar; Natsagdorj, Tseveenmayadag; Xiao, Xiangming

2016-01-01

Chewing lice (Phthiraptera) that parasitize the globally threatened swan goose Anser cygnoides have been long recognized since the early 19th century, but those records were probably biased towards sampling of captive or domestic geese due to the small population size and limited distribution of its wild hosts. To better understand the lice species parasitizing swan geese that are endemic to East Asia, we collected chewing lice from 14 wild geese caught at 3 lakes in northeastern Mongolia. The lice were morphologically identified as 16 Trinoton anserinum (Fabricius, 1805), 11 Ornithobius domesticus Arnold, 2005, and 1 Anaticola anseris (Linnaeus, 1758). These species are known from other geese and swans, but all of them were new to the swan goose. This result also indicates no overlap in lice species between older records and our findings from wild birds. Thus, ectoparasites collected from domestic or captive animals may provide biased information on the occurrence, prevalence, host selection, and host-ectoparasite interactions from those on wild hosts.

Sabin and wild type polioviruses from children who presented with acute flaccid paralysis in Nigeria.

Science.gov (United States)

Adedeji, A O; Okonko, I O; Adu, F D

2012-09-01

Sensitive poliovirus surveillance to detect vaccine-derived-polioviruses will continue to increase in importance. Isolating and identifying poliovirus strains from children of pediatrics age in Nigeria. A total of 120 fecal samples were randomly collected from children under the age of five who presented with acute flaccid paralysis. Samples were tested by tissue culture technique and further characterized by intratypic differentiation testing using ELISA and PCR methods. The study confirmed the presence of 22(18.3%) enteroviral isolates comprising 19(86.4%) polioviruses and 3(13.6%) non-polio enteroviruses. These 19 polioviruses include: Sabin-type poliovirus-1 (15.8%), poliovirus-2 (10.5%), poliovirus-3 (10.5%) and wild-type poliovirus-1 (63.2%) isolates. It showed that poliovirus infection was higher in children ages 6-11 months (18.9%), females (18.4%), northern states (91.0%) with no vaccination record (75.0%). Wild-type poliovirus-1 was isolated from the stool samples of 12(54.6%) children from northern states and in all age groups except 18-23 months. No significant differences (P >0.05) between poliovirus infection and age (18.9% vs. 17.7%; 81.9% vs. 18.2%) and sex (18.3% vs. 18.4%). There was significant differences (Pvaccination (75.0% vs. 0.0%). No wild-type poliovirus was found in those with complete vaccination. This study further confirms the presence of Sabin and wild-type poliovirus among children in Nigeria. The isolation of Sabin strain of poliovirus is advantageous to the polio eradication program as it is capable of inducing natural immunity in susceptible hosts. Transmission of wild-type poliovirus among children with incomplete vaccination poses a serious threat to polio eradication program in Nigeria. Environmental and serological surveillance with larger sample size are important for monitoring poliovirus circulation in Nigeria.

Helminths of Wild Predatory Mammals (Mammalia, Carnivora of Ukraine. Trematodes

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Korol E. N.

2016-08-01

Full Text Available The paper summarises information on 11 species of trematodes parasitic in 9 species of wild carnivorans of Ukraine. The largest number of trematode species (9 was found in the red fox (Vulpes vulpes. Alaria alata (Diplostomidae appeared to be the most common trematode parasite in the studied group; it was found in 4 host species from 9 administrative regions and Crimea.

Repair of gamma radiation damage in wild type and a radiation sensitive mutant of Deinococcus radiodurans

International Nuclear Information System (INIS)

Mizuma, Nagayo

1989-01-01

In an effort to examine production and repair of radiation-induced single and double strand breaks in the DNA, a repair-deficient wild type and a repair-deficient mutant, UV17, of Deinococcus radiodurans were subjected to Co-60 gamma irradiation at a dose rate of 6.3 kGy/hr for wild type and 3.9 kGy/hr for UV17 mutant. The shoulder of the curve of UV17 mutant was narrow but existed with the intercept of 0.7 kGy and the corresponding value of the wild type was 4.2 kGy. Mutant cells exhibited about 6 fold increases in sensitivity for the shoulder relative to the wild type. The D 37 doses in the wild type and the mutant were 0.57 kGy and 0.25 kGy, respectively. From the survival curves, difference in the sensitivity between two strains was mainly due to difference of repair capacity than the number of radiation sensitive target. Sedimentation rate of the main component in the irradiated cells of UV17 mutant increased almost to the level of unirradiated control by the postincubation at 30deg C for 3 hrs. The results indicated that this sensitive mutant also exhibited an ability to restore single strand breaks after exposure to a sublethal dose of 0.6 kGy. When restitution of double strand breaks was analyzed by sedimentation in a neutral sucrose gradient, the wild type showed restitution to DNA-membrane complex from large part of the breaks. For UV17 mutant, the apparent increase in DNA-membrane complex formation was seen after 3 hours incubation. Large part of the decrease in the activities of peak 2 was recovered in the peak 1 for the wild type. For the mutant, there was little restitution to peak 1. Almost free DNA component in UV17 mutant, therefore, was merely degraded into shorter pieces. Restoration of DNA-membrane complex from free DNA derived from gamma-ray induced double strand scission involved closely in the repair of gamma-induced damage and survival. (N.K.)

First reports of ectoparasites collected from wild-caught exotic reptiles in Florida.

Science.gov (United States)

Corn, Joseph L; Mertins, James W; Hanson, Britta; Snow, Skip

2011-01-01

We collected ectoparasites from 27 of 51 wild-caught, free-ranging exotic reptiles examined in Florida from 2003 to 2008. Sampled animals represented eight species, five of which yielded ectoparasites. Reported new parasite distribution records for the United States include the following: the first collection of the African tick Amblyomma latum (Koch) from a wild-caught animal [ball python, Python regius (Shaw)] in the United States; the first collection of the lizard scale mite Hirstiella stamii (Jack) from any wild-caught animal [green iguana, Iguana iguana (L.)]; and the first collection of the lizard scale mite Geckobia hemidactyli (Lawrence) in the continental United States from a wild-caught tropical house gecko, Hemidactylus mabouia (Moreau de Jonnès). We also report the first collections of the Neotropical ticks Amblyomma rotundatum (Koch) and Amblyomma dissimile (Koch) from wild-caught Burmese pythons, Python molurus bivittatus (Kuhl); the first collections of A. dissimile from a wild-caught African savannah monitor, Varanus exanthematicus (Bosc); and from wild-caught green iguanas in the United States; and the first collections of the native chiggers Eutrombicula splendens (Ewing) and Eutrombicula cinnabaris (Ewing) from wild-caught Burmese pythons. These reports may only suggest the diversity of reptile ectoparasites introduced and established in Florida and the new host-parasite relationships that have developed among exotic and native ectoparasites and established exotic reptiles.

Molecular Modeling and Structural Stability of Wild-Type and Mutant CYP51 from Leishmania major: In Vitro and In Silico Analysis of a Laboratory Strain

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Masoud Keighobadi

2018-03-01

Full Text Available Cutaneous leishmaniasis is a neglected tropical disease and a major public health in the most countries. Leishmania major is the most common cause of cutaneous leishmaniasis. In the Leishmania parasites, sterol 14α-demethylase (CYP51, which is involved in the biosynthesis of sterols, has been identified as an attractive target for development of new therapeutic agents. In this study, the sequence and structure of CYP51 in a laboratory strain (MRHO/IR/75/ER of L. major were determined and compared to the wild-type strain. The results showed 19 mutations including seven non-synonymous and 12 synonymous ones in the CYP51 sequence of strain MRHO/IR/75/ER. Importantly, an arginine to lysine substitution at position of 474 resulted in destabilization of CYP51 (ΔΔG = 1.17 kcal/mol in the laboratory strain; however, when the overall effects of all substitutions were evaluated by 100 ns molecular dynamics simulation, the final structure did not show any significant changes (p-value < 0.05 in stability parameter of the strain MRHO/IR/75/ER compared to the wild-type protein. The energy level for the CYP51 of wild-type and MRHO/IR/75/ER strain were −40,027.1 and −39,706.48 Kcal/mol respectively. The overall Root-mean-square deviation (RMSD deviation between two proteins was less than 1 Å throughout the simulation and Root-mean-square fluctuation (RMSF plot also showed no substantial differences between amino acids fluctuation of the both protein. The results also showed that, these mutations were located on the protein periphery that neither interferes with protein folding nor with substrate/inhibitor binding. Therefore, L. major strain MRHO/IR/75/ER is suggested as a suitable laboratory model for studying biological role of CYP51 and inhibitory effects of sterol 14α-demethylase inhibitors.

African origin of the malaria parasite Plasmodium vivax.

Science.gov (United States)

Liu, Weimin; Li, Yingying; Shaw, Katharina S; Learn, Gerald H; Plenderleith, Lindsey J; Malenke, Jordan A; Sundararaman, Sesh A; Ramirez, Miguel A; Crystal, Patricia A; Smith, Andrew G; Bibollet-Ruche, Frederic; Ayouba, Ahidjo; Locatelli, Sabrina; Esteban, Amandine; Mouacha, Fatima; Guichet, Emilande; Butel, Christelle; Ahuka-Mundeke, Steve; Inogwabini, Bila-Isia; Ndjango, Jean-Bosco N; Speede, Sheri; Sanz, Crickette M; Morgan, David B; Gonder, Mary K; Kranzusch, Philip J; Walsh, Peter D; Georgiev, Alexander V; Muller, Martin N; Piel, Alex K; Stewart, Fiona A; Wilson, Michael L; Pusey, Anne E; Cui, Liwang; Wang, Zenglei; Färnert, Anna; Sutherland, Colin J; Nolder, Debbie; Hart, John A; Hart, Terese B; Bertolani, Paco; Gillis, Amethyst; LeBreton, Matthew; Tafon, Babila; Kiyang, John; Djoko, Cyrille F; Schneider, Bradley S; Wolfe, Nathan D; Mpoudi-Ngole, Eitel; Delaporte, Eric; Carter, Richard; Culleton, Richard L; Shaw, George M; Rayner, Julian C; Peeters, Martine; Hahn, Beatrice H; Sharp, Paul M

2014-01-01

Plasmodium vivax is the leading cause of human malaria in Asia and Latin America but is absent from most of central Africa due to the near fixation of a mutation that inhibits the expression of its receptor, the Duffy antigen, on human erythrocytes. The emergence of this protective allele is not understood because P. vivax is believed to have originated in Asia. Here we show, using a non-invasive approach, that wild chimpanzees and gorillas throughout central Africa are endemically infected with parasites that are closely related to human P. vivax. Sequence analyses reveal that ape parasites lack host specificity and are much more diverse than human parasites, which form a monophyletic lineage within the ape parasite radiation. These findings indicate that human P. vivax is of African origin and likely selected for the Duffy-negative mutation. All extant human P. vivax parasites are derived from a single ancestor that escaped out of Africa.

African origin of the malaria parasite Plasmodium vivax

Science.gov (United States)

Liu, Weimin; Li, Yingying; Shaw, Katharina S.; Learn, Gerald H.; Plenderleith, Lindsey J.; Malenke, Jordan A.; Sundararaman, Sesh A.; Ramirez, Miguel A.; Crystal, Patricia A.; Smith, Andrew G.; Bibollet-Ruche, Frederic; Ayouba, Ahidjo; Locatelli, Sabrina; Esteban, Amandine; Mouacha, Fatima; Guichet, Emilande; Butel, Christelle; Ahuka-Mundeke, Steve; Inogwabini, Bila-Isia; Ndjango, Jean-Bosco N.; Speede, Sheri; Sanz, Crickette M.; Morgan, David B.; Gonder, Mary K.; Kranzusch, Philip J.; Walsh, Peter D.; Georgiev, Alexander V.; Muller, Martin N.; Piel, Alex K.; Stewart, Fiona A.; Wilson, Michael L.; Pusey, Anne E.; Cui, Liwang; Wang, Zenglei; Färnert, Anna; Sutherland, Colin J.; Nolder, Debbie; Hart, John A.; Hart, Terese B.; Bertolani, Paco; Gillis, Amethyst; LeBreton, Matthew; Tafon, Babila; Kiyang, John; Djoko, Cyrille F.; Schneider, Bradley S.; Wolfe, Nathan D.; Mpoudi-Ngole, Eitel; Delaporte, Eric; Carter, Richard; Culleton, Richard L.; Shaw, George M.; Rayner, Julian C.; Peeters, Martine; Hahn, Beatrice H.; Sharp, Paul M.

2014-01-01

Plasmodium vivax is the leading cause of human malaria in Asia and Latin America but is absent from most of central Africa due to the near fixation of a mutation that inhibits the expression of its receptor, the Duffy antigen, on human erythrocytes. The emergence of this protective allele is not understood because P. vivax is believed to have originated in Asia. Here we show, using a non-invasive approach, that wild chimpanzees and gorillas throughout central Africa are endemically infected with parasites that are closely related to human P. vivax. Sequence analyses reveal that ape parasites lack host specificity and are much more diverse than human parasites, which form a monophyletic lineage within the ape parasite radiation. These findings indicate that human P. vivax is of African origin and likely selected for the Duffy-negative mutation. All extant human P. vivax parasites are derived from a single ancestor that escaped out of Africa. PMID:24557500

Genetic recombination of tick-borne flaviviruses among wild-type strains.

Science.gov (United States)

Norberg, Peter; Roth, Anette; Bergström, Tomas

2013-06-05

Genetic recombination has been suggested to occur in mosquito-borne flaviviruses. In contrast, tick-borne flaviviruses have been thought to evolve in a clonal manner, although recent studies suggest that recombination occurs also for these viruses. We re-analyzed the data and found that previous conclusions on wild type recombination were probably falsely drawn due to misalignments of nucleotide sequences, ambiguities in GenBank sequences, or different laboratory culture histories suggestive of recombination events in laboratory. To evaluate if reliable predictions of wild type recombination of tick-borne flaviviruses can be made, we analyzed viral strains sequenced exclusively for this study, and other flavivirus sequences retrieved from GenBank. We detected genetic signals supporting recombination between viruses within the three clades of TBEV-Eu, TBEV-Sib and TBEV-Fe, respectively. Our results suggest that the tick-borne encephalitis viruses may undergo recombination under natural conditions, but that geographic barriers restrict most recombination events to involve only closely genetically related viruses. Copyright © 2013 Elsevier Inc. All rights reserved.

Occurrence of tongue worm, Linguatula cf. serrata (Pentastomida: Linguatulidae in wild canids and livestock in south-eastern Australia

Directory of Open Access Journals (Sweden)

Shokoofeh Shamsi

2017-12-01

Full Text Available Pentastomids are obligate zoonotic arthropod parasites utilising canids and vulpids as their definitive hosts and several herbivorous species as their intermediate hosts. Reported only 10 times in Australia over the last 150 years as incidental findings, adult Pentastomids referred to as Linguatula serrata have been encountered in nasal cavities of domestic and wild dogs, and foxes. Nymphs have been reported in cattle and rabbits. In the present study, a number of potential definitive hosts, including red foxes (Vulpes vulpes, wild dogs (Canis lupus dingo and C.l. dingo x C. familiaris and feral cats (Felis catus, and intermediate hosts cattle (Bos taurus, sheep (Ovis aries, feral pigs (Sus scrofa, rabbits (Oryctolagus cuniculus, goats (Capra hircus and a European hare (Lepus europaeus, from the highlands of south-eastern Australia were examined. Of the animals examined 67.6% of wild dogs (n = 37, 14.5% of red foxes (n = 55 and 4.3% of cattle (n = 164 were found to be infected with Pentastomids, herein identified as Linguatula cf. serrata. The common occurrence of the parasite in wild dogs and less frequently in foxes suggests these wild canids have potential to act as a reservoir for infection of livestock, wildlife, domestic dogs and possibly humans. The unexpected high frequency of the parasite in wild dogs and foxes in south-eastern Australia suggests the parasite is more common than previously realised. Of the potential intermediate hosts in the region, only 4.3% of cattle were found to be infected with pentastomid nymphs which suggest the search for the host(s acting as the main intermediate host in the region should continue. Future studies should investigate transmission patterns, health impacts on hosts and whether the parasite has zoonotic significance in Australia. Keywords: Tongue worm, Australia, Linguatulidae, Pentastomida

Wild-Type MIC Distributions for Aminoglycoside and Cyclic Polypeptide Antibiotics Used for Treatment of Mycobacterium tuberculosis Infections▿

Science.gov (United States)

Juréen, P.; Ängeby, K.; Sturegård, E.; Chryssanthou, E.; Giske, C. G.; Werngren, J.; Nordvall, M.; Johansson, A.; Kahlmeter, G.; Hoffner, S.; Schön, T.

2010-01-01

The aminoglycosides and cyclic polypeptides are essential drugs in the treatment of multidrug-resistant tuberculosis, underscoring the need for accurate and reproducible drug susceptibility testing (DST). The epidemiological cutoff value (ECOFF) separating wild-type susceptible strains from non-wild-type strains is an important but rarely used tool for indicating susceptibility breakpoints against Mycobacterium tuberculosis. In this study, we established wild-type MIC distributions on Middlebrook 7H10 medium for amikacin, kanamycin, streptomycin, capreomycin, and viomycin using 90 consecutive clinical isolates and 21 resistant strains. Overall, the MIC variation between and within runs did not exceed ±1 MIC dilution step, and validation of MIC values in Bactec 960 MGIT demonstrated good agreement. Tentative ECOFFs defining the wild type were established for all investigated drugs, including amikacin and viomycin, which currently lack susceptibility breakpoints for 7H10. Five out of seven amikacin- and kanamycin-resistant isolates were classified as susceptible to capreomycin according to the current critical concentration (10 mg/liter) but were non-wild type according to the ECOFF (4 mg/liter), suggesting that the critical concentration may be too high. All amikacin- and kanamycin-resistant isolates were clearly below the ECOFF for viomycin, and two of them were below the ECOFF for streptomycin, indicating that these two drugs may be considered for treatment of amikacin-resistant strains. Pharmacodynamic indices (peak serum concentration [Cmax]/MIC) were more favorable for amikacin and viomycin compared to kanamycin and capreomycin. In conclusion, our data emphasize the importance of establishing wild-type MIC distributions for improving the quality of drug susceptibility testing against Mycobacterium tuberculosis. PMID:20237102

Parasites and parasite stages of free-ranging wild lions (Panthera leo) of northern Tanzania.

Science.gov (United States)

Bjork, K E; Averbeck, G A; Stromberg, B E

2000-03-01

Fecal samples from 33 lions (Panthera leo) in Serengeti National Park and Ngorongoro Crater Conservation Area in northern Tanzania contained 19 different parasites, 12 of which, including Aelurostrongylus sp., a species of Acanthocephala, a species of Anoplocephalidae, Capillaria sp., Demodex sp., Eimeria sp., Habronema sp., Isospora felis, Isospora rivolta, one species of Isospora that was previously undescribed from lions, one species of Trematoda that was previously undescribed from lions, and Trichuris sp., were new reports for lions. Seven other species had been previously reported from lions.

Molecular identification of Taenia serialis coenurosis in a wild Ethiopian gelada (Theropithecus gelada).

Science.gov (United States)

Schneider-Crease, India A; Snyder-Mackler, Noah; Jarvey, Julie C; Bergman, Thore J

2013-11-15

Since morphological identification of a larval Taeniid in geladas (Theropithecus gelada) has produced inconsistent results, genetic information is pivotal for species identification. Nuclear and mitochondrial DNA from a coenurus in a wild gelada were compared to published sequences from multiple Taeniid species, confirming the identification of this parasite as Taenia serialis. A demographic analysis finds age to be a strong predictor of coenuri. Tapeworms rarely employ primates as intermediate hosts, and the presence of T. serialis in a wild gelada population may indicate a substantial ecological shift in this parasite's life cycle. Copyright © 2013 Elsevier B.V. All rights reserved.

Comparative effects of chlorpyrifos in wild type and cannabinoid Cb1 receptor knockout mice

Energy Technology Data Exchange (ETDEWEB)

Baireddy, Praveena; Liu, Jing; Hinsdale, Myron; Pope, Carey, E-mail: carey.pope@okstate.edu

2011-11-15

Endocannabinoids (eCBs) modulate neurotransmission by inhibiting the release of a variety of neurotransmitters. The cannabinoid receptor agonist WIN 55.212-2 (WIN) can modulate organophosphorus (OP) anticholinesterase toxicity in rats, presumably by inhibiting acetylcholine (ACh) release. Some OP anticholinesterases also inhibit eCB-degrading enzymes. We studied the effects of the OP insecticide chlorpyrifos (CPF) on cholinergic signs of toxicity, cholinesterase activity and ACh release in tissues from wild type (+/+) and cannabinoid CB1 receptor knockout (-/-) mice. Mice of both genotypes (n = 5-6/treatment group) were challenged with CPF (300 mg/kg, 2 ml/kg in peanut oil, sc) and evaluated for functional and neurochemical changes. Both genotypes exhibited similar cholinergic signs and cholinesterase inhibition (82-95% at 48 h after dosing) in cortex, cerebellum and heart. WIN reduced depolarization-induced ACh release in vitro in hippocampal slices from wild type mice, but had no effect in hippocampal slices from knockouts or in striatal slices from either genotype. Chlorpyrifos oxon (CPO, 100 {mu}M) reduced release in hippocampal slices from both genotypes in vitro, but with a greater reduction in tissues from wild types (21% vs 12%). CPO had no significant in vitro effect on ACh release in striatum. CPF reduced ACh release in hippocampus from both genotypes ex vivo, but reduction was again significantly greater in tissues from wild types (52% vs 36%). In striatum, CPF led to a similar reduction (20-23%) in tissues from both genotypes. Thus, while CB1 deletion in mice had little influence on the expression of acute toxicity following CPF, CPF- or CPO-induced changes in ACh release appeared sensitive to modulation by CB1-mediated eCB signaling in a brain-regional manner. -- Highlights: Black-Right-Pointing-Pointer C57Bl/6 mice showed dose-related cholinergic toxicity following subcutaneous chlorpyrifos exposure. Black-Right-Pointing-Pointer Wild type and

Comparative effects of chlorpyrifos in wild type and cannabinoid Cb1 receptor knockout mice

International Nuclear Information System (INIS)

Baireddy, Praveena; Liu, Jing; Hinsdale, Myron; Pope, Carey

2011-01-01

Endocannabinoids (eCBs) modulate neurotransmission by inhibiting the release of a variety of neurotransmitters. The cannabinoid receptor agonist WIN 55.212-2 (WIN) can modulate organophosphorus (OP) anticholinesterase toxicity in rats, presumably by inhibiting acetylcholine (ACh) release. Some OP anticholinesterases also inhibit eCB-degrading enzymes. We studied the effects of the OP insecticide chlorpyrifos (CPF) on cholinergic signs of toxicity, cholinesterase activity and ACh release in tissues from wild type (+/+) and cannabinoid CB1 receptor knockout (−/−) mice. Mice of both genotypes (n = 5–6/treatment group) were challenged with CPF (300 mg/kg, 2 ml/kg in peanut oil, sc) and evaluated for functional and neurochemical changes. Both genotypes exhibited similar cholinergic signs and cholinesterase inhibition (82–95% at 48 h after dosing) in cortex, cerebellum and heart. WIN reduced depolarization-induced ACh release in vitro in hippocampal slices from wild type mice, but had no effect in hippocampal slices from knockouts or in striatal slices from either genotype. Chlorpyrifos oxon (CPO, 100 μM) reduced release in hippocampal slices from both genotypes in vitro, but with a greater reduction in tissues from wild types (21% vs 12%). CPO had no significant in vitro effect on ACh release in striatum. CPF reduced ACh release in hippocampus from both genotypes ex vivo, but reduction was again significantly greater in tissues from wild types (52% vs 36%). In striatum, CPF led to a similar reduction (20–23%) in tissues from both genotypes. Thus, while CB1 deletion in mice had little influence on the expression of acute toxicity following CPF, CPF- or CPO-induced changes in ACh release appeared sensitive to modulation by CB1-mediated eCB signaling in a brain-regional manner. -- Highlights: ► C57Bl/6 mice showed dose-related cholinergic toxicity following subcutaneous chlorpyrifos exposure. ► Wild type and cannabinoid CB1 receptor knockout littermates

Flavonoids Promote Haustoria Formation in the Root Parasite Triphysaria versicolor1

Science.gov (United States)

Albrecht, Huguette; Yoder, John I.; Phillips, Donald A.

1999-01-01

Parasitic plants in the Scrophulariaceae develop infective root structures called haustoria in response to chemical signals released from host-plant roots. This study used a simple in vitro assay to characterize natural and synthetic molecules that induce haustoria in the facultative parasite Triphysaria versicolor. Several phenolic acids, flavonoids, and the quinone 2,6-dimethoxy-p-benzoquinone induced haustoria in T. versicolor root tips within hours after treatment. The concentration at which different molecules were active varied widely, the most active being 2,6-dimethoxy-p-benzoquinone and the anthocyanidin peonidin. Maize (Zea mays) seeds are rich sources of molecules that induce T. versicolor haustoria in vitro, and chromatographic analyses indicated that the active molecules present in maize-seed rinses include anthocyanins, other flavonoids, and simple phenolics. The presence of different classes of inducing molecules in seed rinses was substantiated by the observation that maize kernels deficient in chalcone synthase, a key enzyme in flavonoid biosynthesis, released haustoria-inducing molecules, although at reduced levels compared with wild-type kernels. We discuss these results in light of existing models for host perception in the related parasitic plant Striga. PMID:9952454

Research on the ultrafast fluorescence property of thylakoid membranes of the wild-type and mutant rice

Science.gov (United States)

Ren, Zhao-Yu; Xu, Xiao-Ming; Wang, Shui-Cai; Xin, Yue-Yong; He, Jun-Fang; Hou, Xun

2003-10-01

A high yielding rice variety mutant (Oryza sativa L., Zhenhui 249) with low chlorophyll b (Chl b) has been discovered in natural fields. It has a quality character controlled by a pair of recessive genes (nuclear gene). The partial loss of Chl b in content affects the efficiency of light harvest in a light harvest complex (LHC), thus producing the difference of the exciting energy transfer and the efficiency of photochemistry conversion between the mutant and wild-type rice in photosynthetic unit. The efficiency of utilizing light energy is higher in the mutant than that in the wild-type rice relatively. For further discussion of the above-mentioned difference and learning about the mechanism of the increase in the photochemical efficiency of the mutant, the pico-second resolution fluorescence spectrum measurement with delay-frame-scanning single photon counting technique is adopted. Thylakoid membranes of the mutant and the wild-type rice are excited by an Ar+ laser with a pulse width of 120 ps, repetition rate of 4 MHz and wavelength of 514 nm. Compared with the time and spectrum property of exciting fluorescence, conclusions of those ultrafast dynamic experiments are: 1) The speeds of the exciting energy transferred in photo-system I are faster than that in photo-system II in both samples. 2) The speeds of the exciting energy transfer of mutant sample are faster than those of the wild-type. This might be one of the major reasons why the efficiency of photosynthesis is higher in mutant than that in the wild-type rice.

Pathogens of wild maned wolves (Chrysocyon brachyurus) in Brazil.

Science.gov (United States)

de Almeida Curi, Nelson Henrique; Coelho, Carlyle Mendes; de Campos Cordeiro Malta, Marcelo; Magni, Elisa Maria Vaz; Sábato, Marco Aurelio Lima; Araújo, Amanda Soriano; Lobato, Zelia Inês Portela; Santos, Juliana Lúcia Costa; Santos, Hudson Andrade; Ragozo, Alessandra Alves Mara; de Souza, Silvio Luís Pereira

2012-10-01

The maned wolf, Chrysocyon brachyurus, is an endangered Neotropical canid that survives at low population densities. Diseases are a potential threat for its conservation but to date have been poorly studied. We performed clinical evaluations and investigated the presence of infectious diseases through serology and coprologic tests on maned wolves from Galheiro Natural Private Reserve, Perdizes City, Minas Gerais State, southeastern Brazil. Fifteen wolves were captured between 2003 and 2008. We found high prevalences of antibody to canine distemper virus (CDV; 13/14), canine parvovirus (CPV; 4/14), canine adenovirus type 2 (13/14), canine coronavirus (5/11), canine parainfluenza virus (5/5), and Toxoplasma gondii (6/8), along with Ancylostomidae eggs in all feces samples. Antibodies against Leishmania sp. were found in one of 10 maned wolves, and all samples were negative for Neospora caninum. Evidence of high exposure to these viral agents was also observed in unvaccinated domestic dogs from neighboring farms. High prevalence of viral agents and parasites such as CDV, CPV, and Ancylostomidae indicates that this population faces considerable risk of outbreaks and chronic debilitating parasites. This is the first report of exposure to canine parainfluenza virus in Neotropical free-ranging wild canids. Our findings highlight that canine pathogens pose a serious hazard to the viability of maned wolves and other wild carnivore populations in the area and emphasize the need for monitoring and protecting wildlife health in remaining fragments of the Cerrado biome.

Structural Characterization of Lignin in Wild-Type versus COMT Down-Regulated Switchgrass

Energy Technology Data Exchange (ETDEWEB)

Samuel, Reichel [School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA (United States); BioEnergy Science Center, Oak Ridge, TN (United States); Pu, Yunqiao, E-mail: yunqiao.pu@ipst.gatech.edu [BioEnergy Science Center, Oak Ridge, TN (United States); Institute of Paper Science and Technology, Georgia Institute of Technology, Atlanta, GA (United States); Jiang, Nan [School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA (United States); BioEnergy Science Center, Oak Ridge, TN (United States); Fu, Chunxiang [Forage Improvement Division, The Samuel Roberts Noble Foundation, Ardmore, OK (United States); Wang, Zeng-Yu [BioEnergy Science Center, Oak Ridge, TN (United States); Forage Improvement Division, The Samuel Roberts Noble Foundation, Ardmore, OK (United States); Ragauskas, Arthur, E-mail: yunqiao.pu@ipst.gatech.edu [School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA (United States); BioEnergy Science Center, Oak Ridge, TN (United States)

2014-01-20

This study examined the chemical structural characteristics of cellulolytic enzyme lignin isolated from switchgrass focusing on comparisons between wild-type control and caffeic acid 3-O-methyltransferase (COMT) down-regulated transgenic line. Nuclear magnetic resonance techniques including {sup 13}C, {sup 31}P, and two-dimensional {sup 13}C-{sup 1}H heteronuclear single quantum coherence as well as gel permeation chromatography were employed. Compared to the wild-type, the COMT down-regulated transgenic switchgrass lignin demonstrated a decrease in syringyl (S):guaiacyl (G) ratio and p-coumarate:ferulate ratio, an increase in relative abundance of phenylcoumaran unit, and a comparable content of total free phenolic OH groups along with formation of benzodioxane unit. In addition, COMT down-regulation had no significant effects on the lignin molecular weights during its biosynthesis process.

An emerging role for misfolded wild-type SOD1 in sporadic ALS pathogenesis

Directory of Open Access Journals (Sweden)

Melissa S Rotunno

2013-12-01

Full Text Available Amyotrophic lateral sclerosis (ALS is a fatal neurodegenerative disorder that targets motor neurons, leading to paralysis and death within a few years of disease onset. While several genes have been linked to the inheritable, or familial, form of ALS, much less is known about the cause(s of sporadic ALS, which accounts for approximately 90% of ALS cases. Due to the clinical similarities between familial and sporadic ALS, it is plausible that both forms of the disease converge on a common pathway and, therefore, involve common factors. Recent evidence suggests the Cu,Zn-superoxide dismutase (SOD1 protein to be one such factor that is common to both sporadic and familial ALS. In 1993, mutations were uncovered in SOD1 that represent the first known genetic cause of familial ALS. While the exact mechanism of mutant-SOD1 toxicity is still not known today, most evidence points to a gain of toxic function that stems, at least in part, from the propensity of this protein to misfold. In the wild-type SOD1 protein, non-genetic perturbations such as metal depletion, disruption of the quaternary structure, and oxidation, can also induce SOD1 to misfold. In fact, these aforementioned post-translational modifications cause wild-type SOD1 to adopt a toxic conformation that is similar to familial ALS-linked SOD1 variants. These observations, together with the detection of misfolded wild-type SOD1 within human post-mortem sporadic ALS samples, have been used to support the controversial hypothesis that misfolded forms of wild-type SOD1 contribute to sporadic ALS pathogenesis. In this review, we present data from the literature that both support and contradict this hypothesis. We also discuss SOD1 as a potential therapeutic target for both familial and sporadic ALS.

Parasite species of the endangered Iberian wolf (Canis lupus signatus and a sympatric widespread carnivore

Directory of Open Access Journals (Sweden)

Ana Figueiredo

2016-08-01

Full Text Available Parasites have a profound impact on wildlife population dynamics. However, until some years ago, studies on the occurrence and prevalence of wildlife parasites were neglected comparatively with the studies on humans and domestic animals. In this study, we determined the parasite prevalence of two sympatric wild canids: the endangered Iberian wolf (Canis lupus signatus and the widespread red fox (Vulpes vulpes, in central Portugal. From November 2014 to July 2015, fresh fecal samples from both species were collected monthly in several transects distributed throughout the study area. All samples were submitted to several coprological techniques. In total, 6 helminth parasites (Crenosoma vulpis, Angiostrongylus vasorum, Toxocara canis, Trichuris vulpis, Ancylostomatidae, Toxascaris leonina, and a protozoa (Balantidium coli were identified based on size and morphology. The red fox was infected by seven different parasites while the Iberian wolf was infected by four. All parasites present in wolf were also present in the red fox. C. vulpis had the higher prevalence in red fox, while Ancylostomatidae were the most prevalent parasites in wolf. To our knowledge, this is the first study in this isolated subpopulation of the Iberian wolf. Our results show that both carnivores carry parasites that are of concern as they are pathogenic to humans and other wild and domestic animals. We suggest that surveillance programs must also include monitoring protocols of wildlife; particularly endangered species.

Multiparasitism in a wild cat (Leopardus colocolo (Carnivora: Felidae in southern Brazil

Directory of Open Access Journals (Sweden)

Lucas Trevisan Gressler

Full Text Available Abstract Parasitic diseases reflect the health and balance of ecosystems, affecting not only individuals but also entire populations or communities. The aim of this study was to report on the diversity of parasitic helminths detected in the feces of a wild feline in southern Brazil. Parasites were obtained from fecal samples, and four techniques were used for parasitological examination: direct examination, centrifugal flotation with zinc sulfate (Faust technique, simple sedimentation (Hoffman technique and Baermann-Moraes. The parasites were identified through micrometry and morphology, as follows: Ancylostoma sp., Toxocara sp., Trichuridae, Aelurostrongylus abstrusus, Alaria sp., and Spirometra sp. We recorded the genus Ancylostoma parasitizing L. colocolo for the first time.

Microsporidia are natural intracellular parasites of the nematode Caenorhabditis elegans.

Science.gov (United States)

Troemel, Emily R; Félix, Marie-Anne; Whiteman, Noah K; Barrière, Antoine; Ausubel, Frederick M

2008-12-09

For decades the soil nematode Caenorhabditis elegans has been an important model system for biology, but little is known about its natural ecology. Recently, C. elegans has become the focus of studies of innate immunity and several pathogens have been shown to cause lethal intestinal infections in C. elegans. However none of these pathogens has been shown to invade nematode intestinal cells, and no pathogen has been isolated from wild-caught C. elegans. Here we describe an intracellular pathogen isolated from wild-caught C. elegans that we show is a new species of microsporidia. Microsporidia comprise a large class of eukaryotic intracellular parasites that are medically and agriculturally important, but poorly understood. We show that microsporidian infection of the C. elegans intestine proceeds through distinct stages and is transmitted horizontally. Disruption of a conserved cytoskeletal structure in the intestine called the terminal web correlates with the release of microsporidian spores from infected cells, and appears to be part of a novel mechanism by which intracellular pathogens exit from infected cells. Unlike in bacterial intestinal infections, the p38 MAPK and insulin/insulin-like growth factor (IGF) signaling pathways do not appear to play substantial roles in resistance to microsporidian infection in C. elegans. We found microsporidia in multiple wild-caught isolates of Caenorhabditis nematodes from diverse geographic locations. These results indicate that microsporidia are common parasites of C. elegans in the wild. In addition, the interaction between C. elegans and its natural microsporidian parasites provides a system in which to dissect intracellular intestinal infection in vivo and insight into the diversity of pathogenic mechanisms used by intracellular microbes.

No evidence for functional inactivation of wild-type p53 protein by MDM2 overexpression in gastric carcinogenesis

NARCIS (Netherlands)

Blok, P.; Craanen, M. E.; Dekker, W.; Offerhaus, G. J.; Tytgat, G. N.

1998-01-01

Inactivation of wild-type p53 during gastric carcinogenesis is usually caused by mutations within exons 5-8 of the p53 gene leading to mutated, usually immunohistochemically detectable p53 proteins. However, functional inactivation of wild-type p53, mimicking mutational inactivation, may also result

Gene expression profiling in wild-type and metallothionein mutant fibroblast cell lines

Directory of Open Access Journals (Sweden)

ÁNGELA D ARMENDÁRIZ

2006-01-01

Full Text Available The role of metallothioneins (MT in copper homeostasis is of great interest, as it appears to be partially responsible for the regulation of intracellular copper levels during adaptation to extracellular excess of the metal. To further investigate a possible role of MTs in copper metabolism, a genomics approach was utilized to evaluate the role of MT on gene expression. Microarray analysis was used to examine the effects of copper overload in fibroblast cells from normal and MT I and II double knock-out mice (MT-/-. As a first step, we compared genes that were significantly upregulated in wild-type and MT-/- cells exposed to copper. Even though wild-type and mutant cells are undistinguishable in terms of their morphological features and rates of growth, our results show that MT-/- cells do not respond with induction of typical markers of cellular stress under copper excess conditions, as observed in the wild-type cell line, suggesting that the transcription initiation rate or the mRNA stability of stress genes is affected when there is an alteration in the copper store capacity. The functional classification of other up-regulated genes in both cell lines indicates that a large proportion (>80% belong to two major categories: 1 metabolism; and 2 cellular physiological processes, suggesting that at the transcriptional level copper overload induces the expression of genes associated with diverse molecular functions. These results open the possibility to understand how copper homeostasis is being coordinated with other metabolic pathways.

Panitumumab and pegylated liposomal doxorubicin in platinum-resistant epithelial ovarian cancer with KRAS wild-type

DEFF Research Database (Denmark)

Steffensen, Karina Dahl; Waldstrøm, Marianne; Pallisgård, Niels

2013-01-01

OBJECTIVE: The increasing number of negative trials for ovarian cancer treatment has prompted an evaluation of new biologic agents, which in combination with chemotherapy may improve survival. The aim of this study was to investigate the response rate in platinum-resistant, KRAS wild-type ovarian...... cancer patients treated with pegylated liposomal doxorubicin (PLD) supplemented with panitumumab. PATIENTS AND METHODS: Major eligibility criteria were relapsed ovarian/fallopian/peritoneal cancer patients with platinum-resistant disease, measurable disease by GCIG CA125 criteria and KRAS wild-type...

Automatic Detection of Wild-type Mouse Cranial Sutures

DEFF Research Database (Denmark)

Ólafsdóttir, Hildur; Darvann, Tron Andre; Hermann, Nuno V.

, automatic detection of the cranial sutures becomes important. We have previously built a craniofacial, wild-type mouse atlas from a set of 10 Micro CT scans using a B-spline-based nonrigid registration method by Rueckert et al. Subsequently, all volumes were registered nonrigidly to the atlas. Using......, the observer traced the sutures on each of the mouse volumes as well. The observer outperforms the automatic approach by approximately 0.1 mm. All mice have similar errors while the suture error plots reveal that suture 1 and 2 are cumbersome, both for the observer and the automatic approach. These sutures can...

Liver steatosis study_PFAA treated Wild type and PPAR KO mouse data

Data.gov (United States)

U.S. Environmental Protection Agency — Data set 1 consists of the experimental data for the Wild Type and PPAR KO animal study and includes data used to prepare Figures 1-4 and Table 1 of the Das et al,...

Dose selenomethionine have radio-protective effect on cell lines with wild type p53?

International Nuclear Information System (INIS)

Tsuji, K.; Hagihira, T.; Ohnishi, K.; Ohnishi, T.; Matsumoto, H.

2003-01-01

Full text: Selenium compounds are known to have cancer preventive effects. It is reported recently that selenium in the form of selenomethionine (SeMet) can protect cells with wild type p53 from UV-induced cell killing by activating the DNA repair mechanism of p53 tumor suppressor protein via redox factor Ref1 by reducing p53 cysteine residue 275 and 277. In contrast, SeMet has no protective effect on UV-induced cell killing in p53-null cells. If SeMet also has protective effect in cells with wild type p53 on cell killing by photon irradiation, SeMet can be used as normal tissue radio-protector. We examined the effect of SeMet on cell killing by X-ray irradiation in several cell lines with different p53 status at exponentially growing phase. Cell lines used in this experiment were as follows: H1299/neo; human lung cancer cell line of p53 null type tranfected with control vector with no p53, H1299/wp53; wild type p53 transfected counterpart. A172/neo; human glioblastoma cell line with wild type p53, A172/mp53-248; mp53-248 (248-mutant, ARG >TRP) transfected counterpart. SAS/neo; human tongue cancer cell line with wild type p53, and SAS/mp53-248; mp53-248 transfected counterpart. Cells were subcultured at monolayer in D-MEM containing 10% FBS. Survivals of the cells were determined by colony forming ability. Ten-MV linac X-ray was used to irradiate the cells. Exponentially growing cells were incubated with 20μM of SeMet for 15 hours before irradiation. After 24 hours exposure of SeMet, cells were incubated up to two weeks in growth medium for colony formation. Twenty-four hours exposure of 20μM of SeMet had no cytotoxicity on these cell lines. SeMet had no modification effect on cell killing by photon irradiation in H1299/neo, H1299/wp53, SAS/neo, SAS/mp53-248, and A172/mp53-248. On the other hand, SeMet sensitized A172/neo in radiation cell killing. The effects of p53 on interaction of SeMet and photon irradiation differ according to cell lines

ELECTROPHORETIC MOBILITIES OF ESCHERICHIA COLI 0157:H7 AND WILD-TYPE ESCHERICHIA COLI STRAINS

Science.gov (United States)

The electrophoretic mobility (EPM) of a number of human-virulent and "wild-type" Escherichia coli strains in phosphate buffered water was measured. The impact of pH, ionic strength, cation type (valence) and concentration, and bacterial strain on the EPM was investigated. Resul...

The diagnostic activity on wild animals through the description of a ...

African Journals Online (AJOL)

The diagnostic activity on wild animals through the description of a model case report (caseous lymphadenitis by Corynebacterium pseudotuberculosis associated with Pasteurella spp and parasites infection in an alpine ibex – Capra ibex )

Comparison of the nucleotide sequence of wild-type hepatitis - A virus and its attenuated candidate vaccine derivative

International Nuclear Information System (INIS)

Cohen, J.I.; Rosenblum, B.; Ticehurst, J.R.; Daemer, R.; Feinstone, S.; Purcell, R.H.

1987-01-01

Development of attenuated mutants for use as vaccines is in progress for other viruses, including influenza, rotavirus, varicella-zoster, cytomegalovirus, and hepatitis-A virus (HAV). Attenuated viruses may be derived from naturally occurring mutants that infect human or nonhuman hosts. Alternatively, attenuated mutants may be generated by passage of wild-type virus in cell culture. Production of attenuated viruses in cell culture is a laborious and empiric process. Despite previous empiric successes, understanding the molecular basis for attenuation of vaccine viruses could facilitate future development and use of live-virus vaccines. Comparison of the complete nucleotide sequences of wild-type (virulent) and vaccine (attenuated) viruses has been reported for polioviruses and yellow fever virus. Here, the authors compare the nucleotide sequence of wild-type HAV HM-175 with that of a candidate vaccine derivative

Protozoan parasites of four species of wild anurans from a local zoo in Malaysia.

Science.gov (United States)

Mohammad, K N; Badrul, M M; Mohamad, N; Zainal-Abidin, A H

2013-12-01

The parasitic protozoan fauna in sixty-six anurans comprising of Duttaphrynus melanostictus, Phrynoidis juxtaspera, Hylarana erythraea and Polypedates leucomystax collected from Zoo Negara Malaysia was investigated. The distribution and prevalence rate of parasitic species in the digestive tract and blood were examined. Seven species of intestinal protozoa (Opalina ranarum, Cepedea dimidiata, Nycthetorus cordiformis, Entamoeba ranarum, Iodamoeba butschlii, Endamoeba blattae, and Tritrichomonas sp.) and two species of blood protozoa (Lankesterella sp. and Trypanosoma sp.) were recorded. Opalina ranarum was the most common protozoan found in the rectum and intestine (prevalence rate: 34.8%) infecting all host species, with P. juxtaspera heavily infected with the parasite, whereas Tritrichomonas sp. was the least prevalent intestinal species infecting only D. melanostictus. Both Lankesterella sp. and Trypanosoma sp. were found in the blood of H. erythraea.

Positive selection of Plasmodium falciparum parasites with multiple var2csa-type PfEMP1 genes during the course of infection in pregnant women

DEFF Research Database (Denmark)

Sander, Adam F; Salanti, Ali; Lavstsen, Thomas

2011-01-01

multiple genes coding for different VAR2CSA proteins, and parasites with >1 var2csa gene appear to be more common in pregnant women with placental malaria than in nonpregnant individuals. We present evidence that, in pregnant women, parasites containing multiple var2csa-type genes possess a selective...... advantage over parasites with a single var2csa gene. Accumulation of parasites with multiple copies of the var2csa gene during the course of pregnancy was also correlated with the development of antibodies involved in blocking VAR2CSA adhesion. The data suggest that multiplicity of var2csa-type genes...

The fusion protein of wild-type canine distemper virus is a major determinant of persistent infection

International Nuclear Information System (INIS)

Plattet, Philippe; Rivals, Jean-Paul; Zuber, BenoIt; Brunner, Jean-Marc; Zurbriggen, Andreas; Wittek, Riccardo

2005-01-01

The wild-type A75/17 canine distemper virus (CDV) strain induces a persistent infection in the central nervous system but infects cell lines very inefficiently. In contrast, the genetically more distant Onderstepoort CDV vaccine strain (OP-CDV) induces extensive syncytia formation. Here, we investigated the roles of wild-type fusion (F WT ) and attachment (H WT ) proteins in Vero cells expressing, or not, the canine SLAM receptor by transfection experiments and by studying recombinants viruses expressing different combinations of wild-type and OP-CDV glycoproteins. We show that low fusogenicity is not due to a defect of the envelope proteins to reach the cell surface and that H WT determines persistent infection in a receptor-dependent manner, emphasizing the role of SLAM as a potent enhancer of fusogenicity. However, importantly, F WT reduced cell-to-cell fusion independently of the cell surface receptor, thus demonstrating that the fusion protein of the neurovirulent A75/17-CDV strain plays a key role in determining persistent infection

O6-methylguanine-DNA methyltransferase in wild-type and ada mutants of Escherichia coli

International Nuclear Information System (INIS)

Mitra, S.; Pal, B.C.; Foote, R.S.

1982-01-01

O 6 -Methylguanine-DNA methyltransferase is induced in Escherichia coli during growth in low levels of N-methyl-N'-nitro-N-nitrosoguanidine. We have developed a sensitive assay for quantitating low levels of this activity with a synthetic DNA substrate containing 3 H-labeled O 6 -methylguanine as the only modified base. Although both wild-type and adaptation-deficient (ada) mutants of E. coli contained low but comparable numbers (from 13 to 60) of the enzyme molecules per cell, adaptation treatment caused a significant increase of the enzyme in the wild type but not in the ada mutants, suggesting that the ada mutation is in a regulatory locus and not in the structural gene for the methyltransferase

Expression of wild-type and mutant medium-chain acyl-CoA dehydrogenase (MCAD) cDNA in eucaryotic cells

DEFF Research Database (Denmark)

Jensen, T G; Andresen, B S; Bross, P

1992-01-01

An effective EBV-based expression system for eucaryotic cells has been developed and used for the study of the mitochondrial enzyme medium-chain acyl-CoA dehydrogenase (MCAD). 1325 bp of PCR-generated MCAD cDNA, containing the entire coding region, was placed between the SV40 early promoter...... and polyadenylation signals in the EBV-based vector. Both wild-type MCAD cDNA and cDNA containing the prevalent disease-causing mutation A to G at position 985 of the MCAD cDNA were tested. In transfected COS-7 cells, the steady state amount of mutant MCAD protein was consistently lower than the amount of wild......-type human enzyme. The enzyme activity in extracts from cells harbouring the wild-type MCAD cDNA was dramatically higher than in the controls (harbouring the vector without the MCAD gene) while only a slightly higher activity was measured with the mutant MCAD. The mutant MCAD present behaves like wild...

The correlation between the use of personal protective equipment and level wild-type p53 of dental technicians in Surabaya

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Puspa Dila Rohmaniar

2017-03-01

Full Text Available Background: Exposure of metals among dental technicians that come from the working environment can lead to the formation reactive oxygen species (ROS. ROS can cause mutations in the p53 gene (p53. The mutation is transversion mutation GuanineThymine. p53 mutations can lead to low expression of the wild-type p53 protein (p53. Wild-type p53 involved in many biological processes such as regulation of genes involved in cell cycle, cell growth after DNA damage, and apoptosis. However, exposure to metals among dental technicians can be prevented through the use of personal protective equipment (PPE during work. Purpose: The purpose of this study was to analyze the correlation between the use of personal protective equipment to wild-type p53 protein levels among dental technicians in Surabaya. Method: This study was observational analytic with cross sectional approach. 40 samples were taken by random sampling. Data were retrieved through interviews and observations. Wild-type p53 was analyzed from saliva with indirect ELISA method. Analysis of data used Kolmogorov Smirnov normality test and a Pearson correlation test. Value significance was p<0.05 (95% confidence level. Result: There was a significant association between the use of personal protective equipment with wild-type p53 levels with p=0.002 Conclusion: The use PPE properly is positively correlated with the wild-type p53 protein levels of dental technicians in Surabaya.

Toxocara cati (Nematoda, Ascarididae in different wild feline species in Brazil: new host records

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Moisés Gallas

2013-05-01

Full Text Available http://dx.doi.org/10.5007/2175-7925.2013v26n3p117 This is the first detailed description of Toxocara cati parasitizing felines in South America. Seventeen run over wild felines (Leopardus colocolo, Leopardus geoffroyi, Leopardus tigrinus, and Puma yagouaroundi were collected from different towns in the State of Rio Grande do Sul, Brazil. The morphometry of males and females allowed the identification of specimens as being T. cati. The helminths were found in the stomach and intestine of hosts with prevalences of 66.6% in L. colocolo, L. geoffroyi, and L. tigrinus; and 60% in P. yagouaroundi. The ecological parameters were calculated for each host and L. colocolo had the highest infection intensity (22.5 helminths/ host. This is the first report of T. cati parasitizing four wild felines species in southern Brazil, besides a new record of this parasite for two host species.

Genetic regulation of parasite infection: empirical evidence of the functional significance of an IL4 gene SNP on nematode infections in wild primates

Directory of Open Access Journals (Sweden)

Kappeler Peter M

2011-04-01

Full Text Available Abstract Background Susceptibility to parasite infection affects fitness-related processes, such as mate choice and survival, yet its genetic regulation remains poorly understood. Interleukin-4 (IL4 plays a central role in the humoral immune defence against nematode parasite infections, inducing IgE switch and regulation of worm expulsion from the intestines. The evolutionary and functional significance of single nucleotide polymorphisms (SNPs in IL4-genes is known, yet empirical information on the effect of IL4 SNPs on gastro-intestinal infections is lacking. Using samples from a population of wild red-fronted lemurs (Eulemur fulvus rufus, Primates: Lemuridae, from western Madagascar, we explored the association of IL4-gene promoter polymorphisms with nematode infections and investigated a possible functional role of the IL4 polymorphism on male reproductive success. Results Using sequence analyses of lemur DNA we detected a new SNP in the IL4 gene promoter area. Carriers of the genotype T/T showed higher nematode infection intensities than individuals of genotypes C/T and C/C. Genetic population analyses using data from more than 10 years, suggested higher reproductive success of T/T males than expected. Conclusions Our results suggest a regulatory effect of an IL4 gene promoter polymorphism on the intensity of parasite infections in a natural population of red-fronted lemurs, with a seemingly disadvantageous genotype represented in low frequencies. Long-term population analyses, however, point in the direction of a negative frequency-dependent association, giving a fitness advantage to the rare genotype. Due to low frequencies of the genotype in question conclusive evidence of a functional role of IL4 polymorphism cannot be drawn here; still, we suggest the use of IL4 polymorphism as a new molecular tool for quick assessment of individual genetic constitution with regard to nematode infection intensities, contributing to a better

Effect of uremia on HDL composition, vascular inflammation, and atherosclerosis in wild-type mice

DEFF Research Database (Denmark)

Bang, Christian A; Bro, Susanne; Bartels, Emil D

2007-01-01

Wild-type mice normally do not develop atherosclerosis, unless fed cholic acid. Uremia is proinflammatory and increases atherosclerosis 6- to 10-fold in apolipoprotein E-deficient mice. This study examined the effect of uremia on lipoproteins, vascular inflammation, and atherosclerosis in wild...... in cholic acid-fed sham mice. The results suggest that moderate uremia neither induces aortic inflammation nor atherosclerosis in C57BL/6J mice despite increased LDL/HDL cholesterol ratio and altered HDL composition....

Parasites from the Past

DEFF Research Database (Denmark)

Søe, Martin Jensen; Fredensborg, Brian Lund; Nejsum, Peter

will investigate how the diversity of food-borne parasitic infections has changed with cultural and dietary habits, hunting practice and intensity of animal husbandry. This is done by isolating and typing ancient DNA remains from parasite eggs found in archeological samples from across Denmark....

Wild-type minimal inhibitory concentration distributions in bacteria of animal origin in Argentina

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Florencia L Pantozzi

Full Text Available The aim of this study was to determine the antimicrobial resistance profiles of indicator bacteria isolated from domestic animal feces. Minimal inhibitory concentration (MIC was determined by agar dilution. Interpretative criteria on the basis of wild-type MIC distributions and epidemiological cutoff values (ECOFF or ECV were used according to the 'European Committee on Antimicrobial Susceptibility Testing' (EUCAST data. Results from 237 isolates of Escherichia coli showed reduced susceptibility for ampicillin, streptomycin and tetracycline, the antimicrobials commonly used in intensive breeding of pigs and hens. Regarding all the species of the genus Enterococcus spp., there are only ECOFF or ECV for vancomycin. Of the 173 Enterococcus spp. isolated, only one showed reduced susceptibility to vancomycin and was classified as 'non-wild-type' (NWT population. This is the first report in Argentina showing data of epidemiological cutoff values in animal bacteria.

Morphometric, molecular and ecological analyses of the parasites of the sharpsnout seabream Diplodus puntazzo Cetti (Sparidae) from the Spanish Mediterranean: implications for aquaculture.

Science.gov (United States)

Sánchez-García, N; Ahuir-Baraja, A E; Raga, J A; Montero, F E

2015-03-01

One of the fish species with the highest potential for aquaculture is the sharpsnout seabream, Diplodus puntazzo Cetti. Among other aspects, the development of new fish cultures requires studies of potential pathogens that may compromise survival of the fish in captivity. Moreover, both cultured and wild fish can act as sources or reservoirs of pathogens which may negatively affect other well-established cultures. We have studied the parasite fauna of the wild sharpsnout seabream, and monitored the survival of the parasites in culture conditions. The sharpsnout seabream was sampled from two different Spanish localities and examined for parasites. Additionally, 20 fish were maintained in captivity. Ten of them were examined for parasites after a period of 10 days and a further ten fish after another 10 days. All fish were parasitized with at least four species, with 19 parasite species being identified, seven of which were recorded for the first time in the sharpsnout seabream. These included Microcotyle sp., Magnibursatus bartolii, Steringotrema pagelli, Galactosomum sp., Cardiocephaloides longicollis, Caligus ligusticus and Gnathia vorax. We also report the first records of two parasite species in the wild sharpsnout seabream, the polyopisthocotylean monogeneans Atrispinum seminalis and Sparicotyle chrysophrii. Previously, these parasites had only been recorded in farmed sharpsnout seabream. Most parasites in the skin, gills and alimentary tract disappeared under the conditions of captivity, with the exception of the monogeneans of the genus Lamellodiscus. The information provided about the sharpsnout seabream parasite fauna will be useful to prevent possible problems in fish farms due to some parasite species. Many parasites of the sharpsnout seabream recorded in the present study are shared by the main fish species in Mediterranean aquaculture, the gilthead seabream, thus suggesting the possibility of cross-infections.

Parasites of mammals species abundance near zone Chernobyl

International Nuclear Information System (INIS)

Pen'kevich, V.A.

2014-01-01

In wildlife reserve parasitize various types of parasites: arachnids (mites) parasitic insects (horseflies, keds, mosquitoes, gnats, midges), helminths (trematodes, cestodes, nematodes and acanthocephalans) and parasitic protozoa. In quantity: 3 (beaver) to 25 species (wolf). (authors)

A cerebellar learning model of vestibulo-ocular reflex adaptation in wild-type and mutant mice.

Science.gov (United States)

Clopath, Claudia; Badura, Aleksandra; De Zeeuw, Chris I; Brunel, Nicolas

2014-05-21

Mechanisms of cerebellar motor learning are still poorly understood. The standard Marr-Albus-Ito theory posits that learning involves plasticity at the parallel fiber to Purkinje cell synapses under control of the climbing fiber input, which provides an error signal as in classical supervised learning paradigms. However, a growing body of evidence challenges this theory, in that additional sites of plasticity appear to contribute to motor adaptation. Here, we consider phase-reversal training of the vestibulo-ocular reflex (VOR), a simple form of motor learning for which a large body of experimental data is available in wild-type and mutant mice, in which the excitability of granule cells or inhibition of Purkinje cells was affected in a cell-specific fashion. We present novel electrophysiological recordings of Purkinje cell activity measured in naive wild-type mice subjected to this VOR adaptation task. We then introduce a minimal model that consists of learning at the parallel fibers to Purkinje cells with the help of the climbing fibers. Although the minimal model reproduces the behavior of the wild-type animals and is analytically tractable, it fails at reproducing the behavior of mutant mice and the electrophysiology data. Therefore, we build a detailed model involving plasticity at the parallel fibers to Purkinje cells' synapse guided by climbing fibers, feedforward inhibition of Purkinje cells, and plasticity at the mossy fiber to vestibular nuclei neuron synapse. The detailed model reproduces both the behavioral and electrophysiological data of both the wild-type and mutant mice and allows for experimentally testable predictions. Copyright © 2014 the authors 0270-6474/14/347203-13$15.00/0.

Molecular detection and characterization of potentially new Babesia and Theileria species/variants in wild felids from Kenya.

Science.gov (United States)

Githaka, Naftaly; Konnai, Satoru; Kariuki, Edward; Kanduma, Esther; Murata, Shiro; Ohashi, Kazuhiko

2012-10-01

Piroplasms frequently infect domestic and wild carnivores. At present, there is limited information on the occurrence and molecular identity of these tick-borne parasites in wild felids in Kenya. In 2009, a pair of captive lions (Panthare leo) was diagnosed with suspected babesiosis and mineral deficiency at an animal orphanage on the outskirts of Nairobi, Kenya. Blood smears indicated presences of haemoparasites in the erythrocytes, however, no further investigations were conducted to identify the infecting agent. The animals recovered completely following diet supplementation and treatment with anti-parasite drug. In this report, we extracted and detected parasite DNA from the two lions and seven other asymptomatic feline samples; two leopards (Panthera pardus) and five cheetahs (Acinonyx jubatus). Reverse line blot with probes specific for Babesia spp. of felines indicated the presence of new Babesia species or genotypes in the lions and leopards, and unknown Theileria sp. in the cheetahs. Phylogenetic analyses using partial sequences of 18S ribosomal RNA (18S rRNA) gene showed that the parasite infecting the lions belong to the Babesia canis complex, and the parasite variant detected in the leopards clusters in a clade bearing other Babesia spp. reported in wild felids from Africa. The cheetah isolates falls in the Theileria sensu stricto group. Our findings indicate the occurrence of potentially new species or genotypes of piroplams in all three feline species. Copyright © 2012 Elsevier B.V. All rights reserved.

Molecular characterization and functional analysis of pteridine reductase in wild-type and antimony-resistant Leishmania lines.

Science.gov (United States)

de Souza Moreira, Douglas; Ferreira, Rafael Fernandes; Murta, Silvane M F

2016-01-01

Pteridine reductase (PTR1) is an NADPH-dependent reductase that participates in the salvage of pteridines, which are essential to maintain growth of Leishmania. In this study, we performed the molecular characterization of ptr1 gene in wild-type (WTS) and SbIII-resistant (SbR) lines from Leishmania guyanensis (Lg), Leishmania amazonensis (La), Leishmania braziliensis (Lb) and Leishmania infantum (Li), evaluating the chromosomal location, mRNA levels of the ptr1 gene and PTR1 protein expression. PFGE results showed that the ptr1 gene is located in a 797 kb chromosomal band in all Leishmania lines analyzed. Interestingly, an additional chromosomal band of 1070 kb was observed only in LbSbR line. Northern blot results showed that the levels of ptr1 mRNA are increased in the LgSbR, LaSbR and LbSbR lines. Western blot assays using the polyclonal anti-LmPTR1 antibody demonstrated that PTR1 protein is more expressed in the LgSbR, LaSbR and LbSbR lines compared to their respective WTS counterparts. Nevertheless, no difference in the level of mRNA and protein was observed between the LiWTS and LiSbR lines. Functional analysis of PTR1 enzyme was performed to determine whether the overexpression of ptr1 gene in the WTS L. braziliensis and L. infantum lines would change the SbIII-resistance phenotype of transfected parasites. Western blot results showed that the expression level of PTR1 protein was increased in the transfected parasites compared to the non-transfected ones. IC50 analysis revealed that the overexpression of ptr1 gene in the WTS L. braziliensis line increased 2-fold the SbIII-resistance phenotype compared to the non-transfected counterpart. Furthermore, the overexpression of ptr1 gene in the WTS L. infantum line did not change the SbIII-resistance phenotype. These results suggest that the PTR1 enzyme may be implicated in the SbIII-resistance phenotype in L. braziliensis line. Copyright © 2015 Elsevier Inc. All rights reserved.

Survey of gastrointestinal parasite infection in African lion ( Panthera ...

African Journals Online (AJOL)

Little is known about gastrointestinal parasite infections in large carnivores in Africa and what is available is largely from East Africa. We collected faecal samples from nine spotted hyaenas (Crocuta crocuta), 15 lions (Panthera leo) and 13 African wild dog (Lycaon pictus) from Luangwa Valley, Zambia. The most common ...

Mesocestoides sp. (Eucestoda, Mesocestoididae parasitizing four species of wild felines in Southern Brazil Mesocestoides sp. (Eucestoda, Mesocestoididae parasitando quatro espécies de felinos silvestres no Sul do Brasil

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Moisés Gallas

2011-06-01

Full Text Available Leopardus colocolo, Leopardus geoffroyi, Leopardus tigrinus and Puma yagouaroundi are wild feline species endangered mainly due to habitat destruction and vehicle run overs. Seventeen felines hit on the roads were collected in Southern Brazil and examined for parasites. Cestodes were identified as Mesocestoides sp. The parasites were found in the small intestine of the hosts with a prevalence of 66.7% (L. colocolo and L. tigrinus, 60% (P. yagouaroundi and 50% (L. geoffroyi. Rodents and lizards were found in the stomach contents and they possibly were intermediate hosts of Mesocestoides sp. This is the first report of Mesocestoides sp. in wild felines in Brazil.As espécies Leopardus colocolo, Leopardus geoffroyi, Leopardus tigrinus e Puma yagouaroundi, são felídeos silvestres ameaçados de extinção, principalmente pela destruição do hábitat e morte em rodovias. Dezessete felídeos foram coletados atropelados no sul do Brasil e, analisados na pesquisa de parasitos. Cestóides encontrados foram identificados como Mesocestoides sp. Os parasitos foram encontrados no intestino delgado dos hospedeiros com prevalência de 66,7% (L. colocolo e L. tigrinus, 60% (P. yagouaroundi e 50% (L. geoffroyi. Roedores e lagartos foram encontrados no conteúdo estomacal, podendo ser os hospedeiros intermediários para Mesocestoides sp. Este é o primeiro registro de Mesocestoides sp. em felídeos silvestres no Brasil.

Experimental Infection and Clearance of Coccidian Parasites in Mercury-Exposed Zebra Finches.

Science.gov (United States)

Ebers Smith, Jessica H; Cristol, Daniel A; Swaddle, John P

2018-01-01

Mercury is a globally distributed, persistent environmental contaminant that affects the health of many taxa. It can suppress the immune system, which often plays a role in defense against parasites. However, there have been few investigations of whether mercury affects the abilities of animals to resist parasitic infection. Here, we exposed zebra finches to a lifetime dietary exposure of methylmercury (1.2 μg/g wet weight) and experimentally infected them with coccidian parasites to examine the effect of methylmercury exposure on parasitic infection. The mercury-exposed birds did not have an altered immune response (heterophil:lymphocyte ratio) nor a reduced ability to clear the infection. However, mercury-exposed birds tended to have higher parasite loads at the time when we expected the greatest immune response (2-3 weeks post-infection). Although mercury did not greatly influence the infection-course of this parasite in captivity, responses may be more accentuated in the wild where birds face additional immune challenges.

Toxocara cati (Schrank, 1788 (Nematoda, Ascarididae in different wild feline species in Brazil: new host records

Directory of Open Access Journals (Sweden)

Moisés Gallas

2013-09-01

Full Text Available This is the first detailed description of Toxocara cati parasitizing felines in South America. Seventeen run over wild felines (Leopardus colocolo, Leopardus geoffroyi, Leopardus tigrinus, and Puma yagouaroundi were collected from different towns in the State of Rio Grande do Sul, Brazil. The morphometry of males and females allowed the identification of specimens as being T. cati. The helminths were found in the stomach and intestine of hosts with prevalences of 66.6% in L. colocolo, L. geoffroyi, and L. tigrinus; and 60% in P. yagouaroundi. The ecological parameters were calculated for each host and L. colocolo had the highest infection intensity (22.5 helminths/host. This is the first report of T. cati parasitizing four wild felines species in southern Brazil, besides a new record of this parasite for two host species.

Interleukin-1 receptor type I gene-deficient mice are less susceptible to Staphylococcus epidermidis biomaterial-associated infection than are wild-type mice

NARCIS (Netherlands)

Boelens, J. J.; van der Poll, T.; Zaat, S. A.; Murk, J. L.; Weening, J. J.; Dankert, J.

2000-01-01

Elevated concentrations of interleukin-1 (IL-1) were found in tissue surrounding biomaterials infected with Staphylococcus epidermidis. To determine the role of IL-1 in biomaterial-associated infection (BAI), IL-1 receptor type I-deficient (IL-1R(-/-)) and wild-type mice received subcutaneous

Effects of phorbol ester on mitogen-activated protein kinase kinase activity in wild-type and phorbol ester-resistant EL4 thymoma cells.

Science.gov (United States)

Gause, K C; Homma, M K; Licciardi, K A; Seger, R; Ahn, N G; Peterson, M J; Krebs, E G; Meier, K E

1993-08-05

Phorbol ester-sensitive and -resistant EL4 thymoma cell lines differ in their ability to activate mitogen-activated protein kinase (MAPK) in response to phorbol ester. Treatment of wild-type EL4 cells with phorbol ester results in the rapid activations of MAPK and pp90rsk kinase, a substrate for MAPK, while neither kinase is activated in response to phorbol ester in variant EL4 cells. This study examines the activation of MAPK kinase (MAPKK), an activator of MAPK, in wild-type and variant EL4 cells. Phosphorylation of a 40-kDa substrate, identified as MAPK, was observed following in vitro phosphorylation reactions using cytosolic extracts or Mono Q column fractions prepared from phorbol ester-treated wild-type EL4 cells. MAPKK activity coeluted with a portion of the inactive MAPK upon Mono Q anion-exchange chromatography, permitting detection of the MAPKK activity in fractions containing both kinases. This MAPKK activity was present in phorbol ester-treated wild-type cells, but not in phorbol ester-treated variant cells or in untreated wild-type or variant cells. The MAPKK from wild-type cells was able to activate MAPK prepared from either wild-type or variant cells. MAPKK activity could be stimulated in both wildtype and variant EL4 cells in response to treatment of cells with okadaic acid. These results indicate that the failure of variant EL4 cells to activate MAP kinase in response to phorbol ester is due to a failure to activate MAPKK. Therefore, the step that confers phorbol ester resistance to variant EL4 cells lies between the activation of protein kinase C and the activation of MAPKK.

Wild-type and mutated IDH1/2 enzymes and therapy responses.

Science.gov (United States)

Molenaar, Remco J; Maciejewski, Jaroslaw P; Wilmink, Johanna W; van Noorden, Cornelis J F

2018-04-01

Isocitrate dehydrogenase 1 and 2 (IDH1/2) are key enzymes in cellular metabolism, epigenetic regulation, redox states, and DNA repair. IDH1/2 mutations are causal in the development and/or progression of various types of cancer due to supraphysiological production of D-2-hydroxyglutarate. In various tumor types, IDH1/2-mutated cancers predict for improved responses to treatment with irradiation or chemotherapy. The present review discusses the molecular basis of the sensitivity of IDH1/2-mutated cancers with respect to the function of mutated IDH1/2 in cellular processes and their interactions with novel IDH1/2-mutant inhibitors. Finally, lessons learned from IDH1/2 mutations for future clinical applications in IDH1/2 wild-type cancers are discussed.

Prevalence of blood parasites in seabirds - a review

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Quillfeldt Petra

2011-10-01

Full Text Available Abstract Introduction While blood parasites are common in many birds in the wild, some groups seem to be much less affected. Seabirds, in particular, have often been reported free from blood parasites, even in the presence of potential vectors. Results From a literature review of hemosporidian prevalence in seabirds, we collated a dataset of 60 species, in which at least 15 individuals had been examined. These data were included in phylogenetically controlled statistical analyses of hemosporidian prevalence in relation to ecological and life-history parameters. Haemoproteus parasites were common in frigatebirds and gulls, while Hepatozoon occurred in albatrosses and storm petrels, and Plasmodium mainly in penguins. The prevalence of Haemoproteus showed a geographical signal, being lower in species with distribution towards polar environments. Interspecific differences in Plasmodium prevalence were explained by variables that relate to the exposure to parasites, suggesting that prevalence is higher in burrow nesters with long fledgling periods. Measures of Plasmodium, but not Haemoproteus prevalences were influenced by the method, with PCR-based data resulting in higher prevalence estimates. Conclusions Our analyses suggest that, as in other avian taxa, phylogenetic, ecological and life-history parameters determine the prevalence of hemosporidian parasites in seabirds. We discuss how these relationships should be further explored in future studies.

Phase II marker-driven trial of panitumumab and chemotherapy in KRAS wild-type biliary tract cancer

DEFF Research Database (Denmark)

Jensen, L H; Lindebjerg, J; Ploen, J

2012-01-01

BACKGROUND: Combination chemotherapy has proven beneficial in biliary tract cancer and further improvements may be achieved by individualizing treatment based on biomarkers and by adding biological agents. We report the effect of chemotherapy with panitumumab as first-line therapy for KRAS wild....... Combination chemotherapy with panitumumab in patients with KRAS wild-type tumors met the efficacy criteria for future testing in a randomized trial....

A novel ENU-mutation in ankyrin-1 disrupts malaria parasite maturation in red blood cells of mice.

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Andreas Greth

Full Text Available The blood stage of the plasmodium parasite life cycle is responsible for the clinical symptoms of malaria. Epidemiological studies have identified coincidental malarial endemicity and multiple red blood cell (RBC disorders. Many RBC disorders result from mutations in genes encoding cytoskeletal proteins and these are associated with increased protection against malarial infections. However the mechanisms underpinning these genetic, host responses remain obscure. We have performed an N-ethyl-N-nitrosourea (ENU mutagenesis screen and have identified a novel dominant (haploinsufficient mutation in the Ank-1 gene (Ank1(MRI23420 of mice displaying hereditary spherocytosis (HS. Female mice, heterozygous for the Ank-1 mutation showed increased survival to infection by Plasmodium chabaudi adami DS with a concomitant 30% decrease in parasitemia compared to wild-type, isogenic mice (wt. A comparative in vivo red cell invasion and parasite growth assay showed a RBC-autonomous effect characterised by decreased proportion of infected heterozygous RBCs. Within approximately 6-8 hours post-invasion, TUNEL staining of intraerythrocytic parasites, showed a significant increase in dead parasites in heterozygotes. This was especially notable at the ring and trophozoite stages in the blood of infected heterozygous mutant mice compared to wt (p<0.05. We conclude that increased malaria resistance due to ankyrin-1 deficiency is caused by the intraerythrocytic death of P. chabaudi parasites.

Filarioid infections in wild carnivores: a multispecies survey in Romania.

Science.gov (United States)

Ionică, Angela Monica; Matei, Ioana Adriana; D'Amico, Gianluca; Ababii, Jana; Daskalaki, Aikaterini Alexandra; Sándor, Attila D; Enache, Dorin Valter; Gherman, Călin Mircea; Mihalca, Andrei Daniel

2017-07-13

Filarioids are vector-borne parasitic nematodes of vertebrates. In Europe, eight species of filarioids, including zoonotic species, have been reported mainly in domestic dogs, and occasionally in wild carnivores. In Romania, infections with Dirofilaria spp. and Acanthocheilonema reconditum are endemic in domestic dogs. Despite the abundant populations of wild carnivores in the country, their role in the epidemiology of filarioid parasites remains largely unknown. The aim of the present study was to assess the host range, prevalence and distribution of filarioid infections in wild carnivores present in Romania. Between May 2014 and February 2016, 432 spleen samples originating from 14 species of wild carnivores have been tested for the presence of DNA of three species of filarioids (D. immitis, D. repens and A. reconditum). Overall 14 samples (3.24%) were molecularly positive. The most prevalent species was D. immitis (1.62%), accounting for 50% (n = 7) of the positive animals. The prevalence of D. repens was 1.39%, while that of A. reconditum was 0.23%. No co-infections were detected. Dirofilaria immitis DNA was detected in five golden jackals, Canis aureus (7.58%), one red fox, Vulpes vulpes (0.33%), and one wildcat, Felis silvestris (10%). The presence of D. repens DNA was detected in two red foxes (0.66%), two golden jackals (3.03%), one grey wolf (7.14%), and one least weasel, Mustela nivalis (33.33%). Acanthocheilonema reconditum DNA was found only in one red fox (0.33%). The present study provides molecular evidence of filarial infections in wild carnivore species in Romania, suggesting their potential epidemiological role and reports a new host species for D. repens.

A ten-week biochemistry lab project studying wild-type and mutant bacterial alkaline phosphatase.

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Witherow, D Scott

2016-11-12

This work describes a 10-week laboratory project studying wild-type and mutant bacterial alkaline phosphatase, in which students purify, quantitate, and perform kinetic assays on wild-type and selected mutants of the enzyme. Students also perform plasmid DNA purification, digestion, and gel analysis. In addition to simply learning important techniques, students acquire novel biochemical data in their kinetic analysis of mutant enzymes. The experiments are designed to build on students' work from week to week in a way that requires them to apply quantitative analysis and reasoning skills, reinforcing traditional textbook biochemical concepts. Students are assessed through lab reports focused on journal style writing, quantitative and conceptual question sheets, and traditional exams. © 2016 by The International Union of Biochemistry and Molecular Biology, 44(6):555-564, 2016. © 2016 The International Union of Biochemistry and Molecular Biology.

Malaria parasite-synthesized heme is essential in the mosquito and liver stages and complements host heme in the blood stages of infection.

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Viswanathan Arun Nagaraj

Full Text Available Heme metabolism is central to malaria parasite biology. The parasite acquires heme from host hemoglobin in the intraerythrocytic stages and stores it as hemozoin to prevent free heme toxicity. The parasite can also synthesize heme de novo, and all the enzymes in the pathway are characterized. To study the role of the dual heme sources in malaria parasite growth and development, we knocked out the first enzyme, δ-aminolevulinate synthase (ALAS, and the last enzyme, ferrochelatase (FC, in the heme-biosynthetic pathway of Plasmodium berghei (Pb. The wild-type and knockout (KO parasites had similar intraerythrocytic growth patterns in mice. We carried out in vitro radiolabeling of heme in Pb-infected mouse reticulocytes and Plasmodium falciparum-infected human RBCs using [4-(14C] aminolevulinic acid (ALA. We found that the parasites incorporated both host hemoglobin-heme and parasite-synthesized heme into hemozoin and mitochondrial cytochromes. The similar fates of the two heme sources suggest that they may serve as backup mechanisms to provide heme in the intraerythrocytic stages. Nevertheless, the de novo pathway is absolutely essential for parasite development in the mosquito and liver stages. PbKO parasites formed drastically reduced oocysts and did not form sporozoites in the salivary glands. Oocyst production in PbALASKO parasites recovered when mosquitoes received an ALA supplement. PbALASKO sporozoites could infect mice only when the mice received an ALA supplement. Our results indicate the potential for new therapeutic interventions targeting the heme-biosynthetic pathway in the parasite during the mosquito and liver stages.

A multiplex reverse transcription-nested polymerase chain reaction for detection and differentiation of wild-type and vaccine strains of canine distemper virus

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Cui Shang-jin

2010-05-01

Full Text Available Abstract A multiplex reverse transcription-nested polymerase chain reaction (RT-nPCR method was developed for the detection and differentiation of wild-type and vaccine strains of canine distemper virus (CDV. A pair of primers (P1 and P4 specific for CDV corresponding to the highly conserved region of the CDV genome were used as a common primer pair in the first-round PCR of the nested PCR. Primers P2 specific for CDV wild-type strains, were used as the forward primer together with the common reverse primer P4 in the second round of nested PCR. Primers P3, P5 specific for CDV wild-type strain or vaccine strain, were used as the forward primer together with the common reverse primer P4+P6 in the second round of nested PCR. A fragment of 177 bp was amplified from vaccine strain genomic RNA, and a fragment of 247 bp from wild-type strain genomic RNA in the RT-nPCR, and two fragments of 247 bp and 177 bp were amplified from the mixed samples of vaccine and wild-type strains. No amplification was achieved for uninfected cells, or cells infected with Newcastle disease virus (NDV, canine parvovirus (CPV, canine coronavirus (CCV, rabies virus (RV, or canine adenovirus (CAV. The RT-nPCR method was used to detect 30 field samples suspected of canine distemper from Heilongjiang and Jilin Provinces, and 51 samples in Shandong province. As a result of 30 samples, were found to be wild-type-like, and 5 to be vaccine-strain-like. The RT-nPCR method can be used to effectively detect and differentiate wild-type CDV-infected dogs from dogs vaccinated with CDV vaccine, and thus can be used in clinical detection and epidemiological surveillance.

A multiplex reverse transcription-nested polymerase chain reaction for detection and differentiation of wild-type and vaccine strains of canine distemper virus

Science.gov (United States)

2010-01-01

A multiplex reverse transcription-nested polymerase chain reaction (RT-nPCR) method was developed for the detection and differentiation of wild-type and vaccine strains of canine distemper virus (CDV). A pair of primers (P1 and P4) specific for CDV corresponding to the highly conserved region of the CDV genome were used as a common primer pair in the first-round PCR of the nested PCR. Primers P2 specific for CDV wild-type strains, were used as the forward primer together with the common reverse primer P4 in the second round of nested PCR. Primers P3, P5 specific for CDV wild-type strain or vaccine strain, were used as the forward primer together with the common reverse primer P4+P6 in the second round of nested PCR. A fragment of 177 bp was amplified from vaccine strain genomic RNA, and a fragment of 247 bp from wild-type strain genomic RNA in the RT-nPCR, and two fragments of 247 bp and 177 bp were amplified from the mixed samples of vaccine and wild-type strains. No amplification was achieved for uninfected cells, or cells infected with Newcastle disease virus (NDV), canine parvovirus (CPV), canine coronavirus (CCV), rabies virus (RV), or canine adenovirus (CAV). The RT-nPCR method was used to detect 30 field samples suspected of canine distemper from Heilongjiang and Jilin Provinces, and 51 samples in Shandong province. As a result of 30 samples, were found to be wild-type-like, and 5 to be vaccine-strain-like. The RT-nPCR method can be used to effectively detect and differentiate wild-type CDV-infected dogs from dogs vaccinated with CDV vaccine, and thus can be used in clinical detection and epidemiological surveillance. PMID:20433759

Mid-aged and aged wild-type and progestin receptor knockout (PRKO) mice demonstrate rapid progesterone and 3alpha,5alpha-THP-facilitated lordosis.

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Frye, C A; Sumida, K; Lydon, J P; O'Malley, B W; Pfaff, D W

2006-05-01

Progesterone (P) and its 5alpha-reduced metabolite, 3alpha-hydroxy-5alpha-pregnan-20-one (3alpha,5alpha-THP), facilitate sexual behavior of rodents via agonist-like actions at intracellular progestin receptors (PRs) and membrane GABA(A)/benzodiazepine receptor complexes (GBRs), respectively. Given that ovarian secretion of progestins declines with aging, whether or not senescent mice are responsive to progestins was of interest. Homozygous PR knockout (PRKO) or wild-type mice that were between 10-12 (mid-aged) or 20-24 (aged) months of age were administered P or 3alpha,5alpha-THP, and the effect on lordosis were examined. Effects of a progestin-priming regimen that enhances PR-mediated (experiment 1) or more rapid, PR-independent effects of progestins (experiments 2 and 3) on sexual behavior were examined. Levels of P, 3alpha,5alpha-THP, and muscimol binding were examined in tissues from aged mice (experiment 4). Wild-type, but not PRKO, mice were responsive when primed with 17beta-estradiol (E(2); 0.5 microg) and administered P (500 microg, subcutaneously). Mid-aged wild-type mice demonstrated greater increases in lordosis 6 h later compared to their pre-P, baseline test than did aged wild-type mice (experiment 1). Lordosis of younger and older wild-type, but not PRKO, mice was significantly increased within 5 min of intravenous (IV) administration of P (100 ng), compared with E(2)-priming alone (experiment 2). However, wild-type and PRKO mice demonstrated significant increases in lordosis 5 min after IV administration of 3alpha,5alpha-THP, an effect which was more pronounced in mid-aged than in aged animals (100 ng-experiment 3). In tissues from aged wild-type and PRKO mice, levels of P, 3alpha,5alpha-THP, and muscimol binding were increased by P administration (experiment 4). PR binding was lower in the cortex of PRKO than that of wild-type mice. Mid-aged and aged PRKO and wild-type mice demonstrated rapid P or 3alpha,5alpha-THP-facilitated lordosis that may be

Dipylidium caninum (Cyclophyllidea, Dipylidiidae) in a wild carnivore from Brazil.

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Vieira, Fabiano M; Luque, José L; Lima, Sueli de Souza; Neto, Antonio H A de Moraes; Muniz-Pereira, Luís C

2012-01-01

We report Dipylidium caninum for the first time in a wild carnivore in Brazil, the crab-eating fox (Cerdocyon thous). Presence of the cestode could be the consequence of anthropogenic expansion into natural habitats of this host, as this parasite has only previously been reported in domestic hosts in Brazil.

Parasites and parasite management practices of organic and conventional dairy herds in Minnesota.

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Sorge, U S; Moon, R D; Stromberg, B E; Schroth, S L; Michels, L; Wolff, L J; Kelton, D F; Heins, B J

2015-05-01

The objective of this study was to describe the prevalence and practices used to manage internal helminth parasites and external arthropod parasites on organic and conventional dairy herds in Minnesota. All organic (ORG) dairy herds in Minnesota (n=114) and a convenience sample of conventional herds were invited to participate in the study. Thirty-five ORG herds and 28 conventional herds were visited once in summer and fall of 2012. Conventional dairy herds were split into small conventional (SC,conventional herds (MC, ≥200 cows) so that SC herds were comparable in size to the ORG herds. Dairy managers were surveyed to assess their farm management practices and perceptions about parasites, hygiene scores were recorded for adult stock, and fecal samples were collected from a nominal 20 breeding-age heifers to characterize abundance of internal parasites. Nonparametric tests were used to compare fecal egg counts per gram (FEC) among farms grouped by management systems and practices. Organic farms had more designated pasture and were more likely to use rotational grazing compared with conventional farms, but the stocking densities of animals on pasture were similar among farm types. The overall FEC were very low, and only a few individual ORG heifers had FEC >500 eggs/gram. Samples from heifers on ORG farms had significantly more strongyle-type eggs than those on SC and MC farms (ORG: 6.6±2.1; SC: 0.5±0.3; MC: 0.8±0.7), but egg counts of other types of gastrointestinal parasites did not differ significantly among the 3 herd groups. Fly control measures were applied mainly to milking cows and preweaned calves and were used on 88.6% of ORG herds, 60.0% of SC herds, and 91.7% of MC herds. Approximately half of the producers reported having seen skin conditions suggestive of lice or tail mange in their cattle during the previous winter (ORG: 48.6%, SC: 57.1%, MC: 53.9%). Although most conventional producers reported treating these skin conditions, most organic

New records of parasites for culture Cobia, Rachycentron canadum (Perciformes: Rachycentridae in Puerto Rico

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Lucy Bunkley-Williams

2006-12-01

Full Text Available Intensive aquaculture sometimes provides conditions favorable for parasites that are not ordinarily found on culture fishes in the wild, and the use of introduced stocks sometimes introduces non-indigenous species to the habitat. When officially asked about the culture of Cobia Rachycentron canadum (Linnaeus in Puerto Rico, the authors responded that it was unlikely to cause harm. It was assumed that a well-known culture facility in Florida would assure parasite-free stocks. Subsequent examinations of stocked juveniles surprisingly found parasites new to this fish. An outbreak of Slime-blotch disease, Brooklynella hostilis Lom & Nigrilli, 1970 (Dysteriida: Hartmannulidae occurred in juvenile Cobia after they were shipped from Florida and stocked. This apparently represents a local parasite that took advantage of the weakened and/or crowded fish. The universal aquarium and culture superparasite, Marine Ich, Cryptocaryon irritans Brown, 1951 (Colpodia: Ichthyophthiriidae was introduced with a shipment of juvenile Cobia from Florida. This may not be serious, since the parasite occurs worldwide, unless it represents a new strain to Puerto Rico. Marine Costia, Ichthyobodo sp. (Kinetoplastida: Bodonidae was introduced into Puerto Rico with juvenile Cobia shipped from Florida. This parasite has caused some severe problems in aquaculture hatcheries in Hawaii and Texas after it was introduced with cultured organisms. Thus far, it has not caused any problems locally, but Puerto Rico lacks the marine hatchery facilities where such outbreaks would occur. The question of whether it is established locally will have to wait the development of similar facilities in Puerto Rico. These three species of parasites represent new host records for Cobia. The non-indigenous Ichthyobodo sp. represents new locality records for the tropical Atlantic, Caribbean, and Florida and Puerto Rico. Cobia mature more quickly in culture than in the wild and thus female Cobia

Checklist of helminths found in Patagonian wild mammals.

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Fugassa, Martin H

2015-09-03

Using available reports, a checklist of the recorded helminth parasites of wild mammals from Patagonia was generated. Records of parasites found in Patagonia were included, together with records from mammals in áreas outside of Patagonia but whose range extends into Patagonia. Information about the host, localities, and references were also included. A total of 1323 records (224 Cestoda, 167 Trematoda, 894 Nematoda, 34 Acanthocephala, and 4 Pentastomida) belonging to 452 helminth species (77 Cestoda, 76 Trematoda, 277 Nematoda, 21 Acanthocephala, and 1 Pentastomida) found in 57 native mammals (22 Rodentia, 4 Didelphimorphia 1 Microbiotheria, 7 Chiroptera, 5 Cingulata, and 13 Carnivora) were listed. However, only 10.6 % of the reports were conducted on samples from Patagonia and corresponded to 25% of mammals in the region. In addition, many studies were made on a few species and, for example, 52% corresponded to studies made on Lama guanicoe. This suggests the need to increase efforts to know the parasitic fauna in a peculiar region as is the Patagonia. This is the first compilation of the helminth parasites of mammals in Argentine Patagonia and is important for parasitological and paleoparasitological studies.

The peculiarity of dynamic of helminth community of wild ungulate animals in the condition of Poles'e reserve

International Nuclear Information System (INIS)

Odintsova, T.M.

1998-01-01

It was analysed the dynamic of helminth community of wild animals in the condition of Poles'e reserve and it was shown that radiation contamination had great influence at the settled community of parasite worms resulting in disappearance or sharp diminution of species quantity that were common for wild ungulate animals and domestics cattle. It was concluded that stabilisation of helminth community of wild ungulate animals had not yet achieved

BACKYARD TURKEYS AS DISEASES RESERVORY FOR WILD BIRDS AND POULTRY IN THREE ECOSYSTEMS OF THE MEXICAN COAST

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Marco Antonio Camacho-Escobar

2008-12-01

Full Text Available To identify the kind of avian diseases could be transmits the backyard turkeys to the Oaxaca's Coast wild life and poultry, a clinical sanitary evaluation was performed in backyard turkeys who grassing on places that could be contact with wild life, in three different ecosystems: cloud forest, medium jungle deciduous and palm trees. The evaluation was performed on six male turkeys with a year and a half old, six female with six months of age, and six poults with less of eight months of age. The laboratory tests included: necropsy for clinical diagnosis of diseases and for a hystopathological examination of tissues; Hemagglutination Inhibition Tests to diagnose Newcastle Disease and Avian Influenza. Serum Plate Agglutination Test to identify antibodies against Mycoplasma gallisepticum, Mycoplasma synoviae and Salmonella pullorum, ELISA to identify Infectious Bronchitis and Infectious Bursal Disease. In addition, laboratory analyses were done to find internal and external parasites. The frequency of diseases was estimated with descriptive statistics and the correlation between Ecosystem X Turkeys Age was calculated with Pearson's correlation coefficient. Was identify Avian Pox, antibodies from Newcastle Disease, Avian Influenza, Infectious Bronchitis, Infectious Bursal Disease; Fowl Typhoid, Colibacillocis, Staphylococcosis, Infectious Sinusitis, Infectious Synovitis. The internal parasites identified were Ascaridia gallinae, Eimeria dispersa, Eimeria meleagridis, Heterakis gallinae and Tetramenes sp; and the external parasite Dermanyssus gallinae. All the diseases and parasitic diseases are dangerous for the poultry and the wild life. A relationship exist between ecosystem and diseases at different ages in backyard turkeys.

Changes in fatty acid content and composition between wild type and CsHMA3 overexpressing Camelina sativa under heavy-metal stress.

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Park, Won; Feng, Yufeng; Kim, Hyojin; Suh, Mi Chung; Ahn, Sung-Ju

2015-09-01

Under heavy-metal stress, CsHMA3 overexpressing transgenic Camelina plants displayed not only a better quality, but also a higher quantity of unsaturated fatty acids in their seeds compared with wild type. Camelina sativa L. belongs to the Brassicaceae family and is frequently used as a natural vegetable oil source, as its seeds contain a high content of fatty acids. In this study, we observed that, when subjected to heavy metals (Cd, Co, Zn and Pb), the seeds of CsHMA3 (Heavy-Metal P1B-ATPase 3) transgenic lines retained their original golden yellow color and smooth outline, unlike wild-type seeds. Furthermore, we investigated the fatty acids content and composition of wild type and CsHMA3 transgenic lines after heavy metal treatments compared to the control. The results showed higher total fatty acid amounts in seeds of CsHMA3 transgenic lines compared with those in wild-type seeds under heavy-metal stresses. In addition, the compositions of unsaturated fatty acids-especially 18:1 (oleic acid), 18:2 (linoleic acid; only in case of Co treatment), 18:3 (linolenic acid) and 20:1 (eicosenoic acid)-in CsHMA3 overexpressing transgenic lines treated with heavy metals were higher than those of wild-type seeds under the same conditions. Furthermore, reactive oxygen species (ROS) contents in wild-type leaves and roots when treated with heavy metal were higher than in CsHMA3 overexpressing transgenic lines. These results indicate that overexpression of CsHMA3 affects fatty acid composition and content-factors that are responsible for the fuel properties of biodiesel-and can alleviate ROS accumulation caused by heavy-metal stresses in Camelina. Due to these factors, we propose that CsHMA3 transgenic Camelina can be used for phytoremediation of metal-contaminated soil as well as for oil production.

The Use of EGFR Tyrosine Kinase Inhibitors in EGFR Wild-Type Non-Small-Cell Lung Cancer.

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Stinchcombe, Thomas E

2016-04-01

The objective response rate and progression-free survival observed with epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKIs) in patients with metastatic epidermal growth factor receptor (EGFR) wild-type non-small cell lung cancer (NSCLC) are modest. The adverse events associated with EGFR TKIs are manageable but they must be considered in the context of the limited efficacy. The development of anti-PD-1 immunotherapy as second-line therapy has reduced the role of EGFR TKIs in EGFR wild-type NSCLC. Recently, there has been increased recognition of the benefit of the earlier integration of palliative care and symptom management, and this is reasonable alternative to treatment with an EGFR TKI for many patients. My practice pattern for patients with EGFR wild-type NSCLC is platinum-based chemotherapy as first-line therapy, immunotherapy as second-line therapy, and single-agent chemotherapy as third-line therapy for patients with preserved performance status who want to pursue further therapy. Only a small proportion of patients are eligible for fourth-line therapy, and I prefer to enroll them in clinical trials rather than use EGFR TKIs. I suspect that the use of EGFR TKIs in clinical use and as a comparator arm for clinical trials will continue to decline over the next several years.

The exported chaperone Hsp70-x supports virulence functions for Plasmodium falciparum blood stage parasites

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Charnaud, Sarah C.; Dixon, Matthew W. A.; Nie, Catherine Q.; Chappell, Lia; Sanders, Paul R.; Nebl, Thomas; Hanssen, Eric; Berriman, Matthew; Chan, Jo-Anne; Blanch, Adam J.; Beeson, James G.; Rayner, Julian C.; Przyborski, Jude M.; Tilley, Leann; Crabb, Brendan S.

2017-01-01

Malaria is caused by five different Plasmodium spp. in humans each of which modifies the host erythrocyte to survive and replicate. The two main causes of malaria, P. falciparum and P. vivax, differ in their ability to cause severe disease, mainly due to differences in the cytoadhesion of infected erythrocytes (IE) in the microvasculature. Cytoadhesion of P. falciparum in the brain leads to a large number of deaths each year and is a consequence of exported parasite proteins, some of which modify the erythrocyte cytoskeleton while others such as PfEMP1 project onto the erythrocyte surface where they bind to endothelial cells. Here we investigate the effects of knocking out an exported Hsp70-type chaperone termed Hsp70-x that is present in P. falciparum but not P. vivax. Although the growth of Δhsp70-x parasites was unaffected, the export of PfEMP1 cytoadherence proteins was delayed and Δhsp70-x IE had reduced adhesion. The Δhsp70-x IE were also more rigid than wild-type controls indicating changes in the way the parasites modified their host erythrocyte. To investigate the cause of this, transcriptional and translational changes in exported and chaperone proteins were monitored and some changes were observed. We propose that PfHsp70-x is not essential for survival in vitro, but may be required for the efficient export and functioning of some P. falciparum exported proteins. PMID:28732045

The exported chaperone Hsp70-x supports virulence functions for Plasmodium falciparum blood stage parasites.

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Sarah C Charnaud

Full Text Available Malaria is caused by five different Plasmodium spp. in humans each of which modifies the host erythrocyte to survive and replicate. The two main causes of malaria, P. falciparum and P. vivax, differ in their ability to cause severe disease, mainly due to differences in the cytoadhesion of infected erythrocytes (IE in the microvasculature. Cytoadhesion of P. falciparum in the brain leads to a large number of deaths each year and is a consequence of exported parasite proteins, some of which modify the erythrocyte cytoskeleton while others such as PfEMP1 project onto the erythrocyte surface where they bind to endothelial cells. Here we investigate the effects of knocking out an exported Hsp70-type chaperone termed Hsp70-x that is present in P. falciparum but not P. vivax. Although the growth of Δhsp70-x parasites was unaffected, the export of PfEMP1 cytoadherence proteins was delayed and Δhsp70-x IE had reduced adhesion. The Δhsp70-x IE were also more rigid than wild-type controls indicating changes in the way the parasites modified their host erythrocyte. To investigate the cause of this, transcriptional and translational changes in exported and chaperone proteins were monitored and some changes were observed. We propose that PfHsp70-x is not essential for survival in vitro, but may be required for the efficient export and functioning of some P. falciparum exported proteins.

Establishment of new transmissible and drug-sensitive human immunodeficiency virus type 1 wild types due to transmission of nucleoside analogue-resistant virus.

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de Ronde, A; van Dooren, M; van Der Hoek, L; Bouwhuis, D; de Rooij, E; van Gemen, B; de Boer, R; Goudsmit, J

2001-01-01

Sequence analysis of human immunodeficiency virus type 1 (HIV-1) from 74 persons with acute infections identified eight strains with mutations in the reverse transcriptase (RT) gene at positions 41, 67, 68, 70, 215, and 219 associated with resistance to the nucleoside analogue zidovudine (AZT). Follow-up of the fate of these resistant HIV-1 strains in four newly infected individuals revealed that they were readily replaced by sensitive strains. The RT of the resistant viruses changed at amino acid 215 from tyrosine (Y) to aspartic acid (D) or serine (S), with asparagine (N) as a transient intermediate, indicating the establishment of new wild types. When we introduced these mutations and the original threonine (T)-containing wild type into infectious molecular clones and assessed their competitive advantage in vitro, the order of fitness was in accord with the in vivo observations: 215Y types with D, S, or N residues at position 215 may be warranted in order to estimate the threat to long-term efficacy of regimens including nucleoside analogues.

Black bear parathyroid hormone has greater anabolic effects on trabecular bone in dystrophin-deficient mice than in wild type mice.

Science.gov (United States)

Gray, Sarah K; McGee-Lawrence, Meghan E; Sanders, Jennifer L; Condon, Keith W; Tsai, Chung-Jui; Donahue, Seth W

2012-09-01

Duchenne muscular dystrophy (DMD) is an X-linked neuromuscular disease that has deleterious consequences in muscle and bone, leading to decreased mobility, progressive osteoporosis, and premature death. Patients with DMD experience a higher-than-average fracture rate, particularly in the proximal and distal femur and proximal tibia. The dystrophin-deficient mdx mouse is a model of DMD that demonstrates muscle degeneration and fibrosis and osteoporosis. Parathyroid hormone, an effective anabolic agent for post-menopausal and glucocorticoid-induced osteoporosis, has not been explored for DMD. Black bear parathyroid hormone (bbPTH) has been implicated in the maintenance of bone properties during extended periods of disuse (hibernation). We cloned bbPTH and found 9 amino acid residue differences from human PTH. Apoptosis was mitigated and cAMP was activated by bbPTH in osteoblast cultures. We administered 28nmol/kg of bbPTH 1-84 to 4-week old male mdx and wild type mice via daily (5×/week) subcutaneous injection for 6 weeks. Vehicle-treated mdx mice had 44% lower trabecular bone volume fraction than wild type mice. No changes were found in femoral cortical bone geometry or mechanical properties with bbPTH treatment in wild type mice, and only medio-lateral moment of inertia changed with bbPTH treatment in mdx femurs. However, μCT analyses of the trabecular regions of the distal femur and proximal tibia showed marked increases in bone volume fraction with bbPTH treatment, with a greater anabolic response (7-fold increase) in mdx mice than wild type mice (2-fold increase). Trabecular number increased in mdx long bone, but not wild type bone. Additionally, greater osteoblast area and decreased osteoclast area were observed with bbPTH treatment in mdx mice. The heightened response to PTH in mdx bone compared to wild type suggests a link between dystrophin deficiency, altered calcium signaling, and bone. These findings support further investigation of PTH as an anabolic

Effects of age and liquid holding on the UV-radiation sensitivities of wild-type and mutant Caenorhabditis elegans dauer larvae

Energy Technology Data Exchange (ETDEWEB)

Hartman, P S

1984-01-01

The dauer larva is a facultative developmental stage in the life cycle of the nematode Caenorhabditis elegans. Dauer larvae, which can survive under starvation for over 60 days, resume normal development when feeding is resumed. Wild-type (N2) and 4 radiation-sensitive (rad) mutant dauer larvae were tested for their abilities to develop into adults after UV-irradiation. The rad-3 mutant was over 30 times as sensitive as N2; rad-1, rad-2 and rad-7 mutants were not hypersensitive. Irradiation also delayed development in survivors. Wild-type dauer larvae did not differ in radiation sensitivity from 0 through 50 days of age. There was no liquid holding recovery (LHR); that is, survival did not increase when wild-type dauer larvae were held in buffer after irradiation. (orig.). 28 refs.; 4 figs.

PBI creams: a spontaneously mutated mouse strain showing wild animal-type reactivity.

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Hendrie, C A; Van Driel, K S; Talling, J C; Inglis, I R

2001-01-01

PBI creams are mice derived from warfarin-resistant wild stock that has been maintained under laboratory conditions since the 1970s. This study compares their behaviour to that of laboratory mice and wild house and wood mice. Animals were tested in a black/white box and a 2.64x1.4 m runway. In the black/white box, the behaviour of PBI creams was not significantly different from that of house mice and differed most from that of laboratory mice. Notably, the PBI creams showed the greatest activity and escape-orientated behaviours. When animals were approached by the experimenter in the open runway test, the PBI creams had higher flight speeds than both house and wood mice, whilst laboratory mice failed to respond. In the closed runway test where the animals could not escape, the PBI creams, house mice and wood mice all turned and attempted to run past the approaching experimenter, whilst the laboratory mice again failed to react. At the end of this test session, the time taken to catch each animal was recorded. It took less than 5 s to catch laboratory mice but significantly longer to catch the wild strains and the PBI creams (90-100 s for the latter). In these tests, the PBI creams showed wild animal-type reactivity, and as this behaviour has been retained in the laboratory colony for over 30 years, these animals may be useful in the study of the physiological and genetic basis of fear/anxiety in mice.

Genotyping assay for differentiation of wild-type and vaccine viruses in subjects immunized with live attenuated influenza vaccine.

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Victoria Matyushenko

Full Text Available Live attenuated influenza vaccines (LAIVs are considered as safe and effective tool to control influenza in different age groups, especially in young children. An important part of the LAIV safety evaluation is the detection of vaccine virus replication in the nasopharynx of the vaccinees, with special attention to a potential virus transmission to the unvaccinated close contacts. Conducting LAIV clinical trials in some geographical regions with year-round circulation of influenza viruses warrants the development of robust and reliable tools for differentiating vaccine viruses from wild-type influenza viruses in nasal pharyngeal wash (NPW specimens of vaccinated subjects. Here we report the development of genotyping assay for the detection of wild-type and vaccine-type influenza virus genes in NPW specimens of young children immunized with Russian-backbone seasonal trivalent LAIV using Sanger sequencing from newly designed universal primers. The new primer set allowed amplification and sequencing of short fragments of viral genes in NPW specimens and appeared to be more sensitive than conventional real-time RT-PCR protocols routinely used for the detection and typing/subtyping of influenza virus in humans. Furthermore, the new assay is capable of defining the origin of wild-type influenza virus through BLAST search with the generated sequences of viral genes fragments.

Mercury concentrations in wild mink (Mustela vison) and river otters (Lontra canadensis) collected from eastern and Atlantic Canada: relationship to age and parasitism.

Science.gov (United States)

Klenavic, Katherine; Champoux, Louise; Mike, O'Brien; Daoust, Pierre-Y; Evans, R Douglas; Evans, Hayla E

2008-11-01

Total mercury (Hg) concentrations were measured in the fur, brain and liver of wild mink (Mustela vison) and river otters (Lontra canadensis) collected from eastern and Atlantic Canada. Total Hg concentrations in fur were strongly correlated with levels in the brain and liver. There was no difference in tissue concentrations between male and female mink; however, female otters had significantly higher fur, brain and liver Hg levels than males. Similarly, there was not a significant relationship between Hg concentration and age of mink, whereas in otters, Hg concentrations in all three tissues decreased significantly with age. In both species, only a very small percentage of the variability in Hg concentration was explained by age. After adjusting the data for site-to-site differences in Hg levels, Hg concentrations in the fur of mink infected by the parasite, Dioctophyma renale, were found to be significantly higher than Hg levels in uninfected mink.

Salmon lice – impact on wild salmonids and salmon aquaculture

Science.gov (United States)

Torrissen, O; Jones, S; Asche, F; Guttormsen, A; Skilbrei, O T; Nilsen, F; Horsberg, T E; Jackson, D

2013-01-01

Salmon lice, Lepeophtheirus salmonis, are naturally occurring parasites of salmon in sea water. Intensive salmon farming provides better conditions for parasite growth and transmission compared with natural conditions, creating problems for both the salmon farming industry and, under certain conditions, wild salmonids. Salmon lice originating from farms negatively impact wild stocks of salmonids, although the extent of the impact is a matter of debate. Estimates from Ireland and Norway indicate an odds ratio of 1.1:1-1.2:1 for sea lice treated Atlantic salmon smolt to survive sea migration compared to untreated smolts. This is considered to have a moderate population regulatory effect. The development of resistance against drugs most commonly used to treat salmon lice is a serious concern for both wild and farmed fish. Several large initiatives have been taken to encourage the development of new strategies, such as vaccines and novel drugs, for the treatment or removal of salmon lice from farmed fish. The newly sequenced salmon louse genome will be an important tool in this work. The use of cleaner fish has emerged as a robust method for controlling salmon lice, and aquaculture production of wrasse is important towards this aim. Salmon lice have large economic consequences for the salmon industry, both as direct costs for the prevention and treatment, but also indirectly through negative public opinion. PMID:23311858

Unique Safety Issues Associated with Virus Vectored Vaccines: Potential for and Theoretical Consequences of Recombination with Wild Type Virus Strains

Science.gov (United States)

Condit, Richard C.; Williamson, Anna-Lise; Sheets, Rebecca; Seligman, Stephen J.; Monath, Thomas P.; Excler, Jean-Louis; Gurwith, Marc; Bok, Karin; Robertson, James S.; Kim, Denny; Hendry, Michael; Singh, Vidisha; Mac, Lisa M.; Chen, Robert T.

2016-01-01

In 2003 and 2013, the World Health Organization convened informal consultations on characterization and quality aspects of vaccines based on live virus vectors. In the resulting reports, one of several issues raised for future study was the potential for recombination of virus-vectored vaccines with wild type pathogenic virus strains. This paper presents an assessment of this issue formulated by the Brighton Collaboration. To provide an appropriate context for understanding the potential for recombination of virus-vectored vaccines, we review briefly the current status of virus vectored vaccines, mechanisms of recombination between viruses, experience with recombination involving live attenuated vaccines in the field, and concerns raised previously in the literature regarding recombination of virus-vectored vaccines with wild type virus strains. We then present a discussion of the major variables that could influence recombination between a virus-vectored vaccine and circulating wild type virus and the consequences of such recombination, including intrinsic recombination properties of the parent virus used as a vector; sequence relatedness of vector and wild virus; virus host range, pathogenesis and transmission; replication competency of vector in target host; mechanism of vector attenuation; additional factors potentially affecting virulence; and circulation of multiple recombinant vectors in the same target population. Finally, we present some guiding principles for vector design and testing intended to anticipate and mitigate the potential for and consequences of recombination of virus-vectored vaccines with wild type pathogenic virus strains. PMID:27346303

A novel soluble immune-type receptor (SITR in teleost fish: carp SITR is involved in the nitric oxide-mediated response to a protozoan parasite.

Directory of Open Access Journals (Sweden)

Carla M S Ribeiro

2011-01-01

Full Text Available The innate immune system relies upon a wide range of germ-line encoded receptors including a large number of immunoglobulin superfamily (IgSF receptors. Different Ig-like immune receptor families have been reported in mammals, birds, amphibians and fish. Most innate immune receptors of the IgSF are type I transmembrane proteins containing one or more extracellular Ig-like domains and their regulation of effector functions is mediated intracellularly by distinct stimulatory or inhibitory pathways.Carp SITR was found in a substracted cDNA repertoire from carp macrophages, enriched for genes up-regulated in response to the protozoan parasite Trypanoplasma borreli. Carp SITR is a type I protein with two extracellular Ig domains in a unique organisation of a N-proximal V/C2 (or I- type and a C-proximal V-type Ig domain, devoid of a transmembrane domain or any intracytoplasmic signalling motif. The carp SITR C-proximal V-type Ig domain, in particular, has a close sequence similarity and conserved structural characteristics to the mammalian CD300 molecules. By generating an anti-SITR antibody we could show that SITR protein expression was restricted to cells of the myeloid lineage. Carp SITR is abundantly expressed in macrophages and is secreted upon in vitro stimulation with the protozoan parasite T. borreli. Secretion of SITR protein during in vivo T. borreli infection suggests a role for this IgSF receptor in the host response to this protozoan parasite. Overexpression of carp SITR in mouse macrophages and knock-down of SITR protein expression in carp macrophages, using morpholino antisense technology, provided evidence for the involvement of carp SITR in the parasite-induced NO production.We report the structural and functional characterization of a novel soluble immune-type receptor (SITR in a teleost fish and propose a role for carp SITR in the NO-mediated response to a protozoan parasite.

Exploratory biomarker analysis for treatment response in KRAS wild type metastatic colorectal cancer patients who received cetuximab plus irinotecan

International Nuclear Information System (INIS)

Kim, Seung Tae; Ahn, Tae Jin; Lee, Eunjin; Do, In-Gu; Lee, Su Jin; Park, Se Hoon; Park, Joon Oh; Park, Young Suk; Lim, Ho Yeong; Kang, Won Ki; Kim, Suk Hyeong; Lee, Jeeyun; Kim, Hee Cheol

2015-01-01

More than half of the patients selected based on KRAS mutation status fail to respond to the treatment with cetuximab in metastatic colorectal cancer (mCRC). We designed a study to identify additional biomarkers that could act as indicators for cetuximab treatment in mCRC. We investigated 58 tumor samples from wild type KRAS CRC patients treated with cetuximab plus irinotecan (CI). We conducted the genotyping for mutations in either BRAF or PIK3CA and profiled comprehensively the expression of 522 kinase genes. BRAF mutation was detected in 5.1 % (3/58) of patients. All 50 patients showed wild type PIK3CA. Gene expression patterns that categorized patients with or without the disease control to CI were compared by supervised classification analysis. PSKH1, TLK2 and PHKG2 were overexpressed significantly in patients with the disease control to IC. The higher expression value of PSKH1 (r = 0.462, p < 0.001) and TLK2 (r = 0.361, p = 0.005) had the significant correlation to prolonged PFS. The result of this work demonstrated that expression nature of kinase genes such as PSKH1, TLK2 and PHKG2 may be informative to predict the efficacy of CI in wild type KRAS CRC. Mutations in either BRAF or PIK3CA were rare subsets in wild type KRAS CRC

MLH1-deficient Colorectal Carcinoma With Wild-type BRAF and MLH1 Promoter Hypermethylation Harbor KRAS Mutations and Arise From Conventional Adenomas.

Science.gov (United States)

Farchoukh, Lama; Kuan, Shih-Fan; Dudley, Beth; Brand, Randall; Nikiforova, Marina; Pai, Reetesh K

2016-10-01

Between 10% and 15% of colorectal carcinomas demonstrate sporadic DNA mismatch-repair protein deficiency as a result of MLH1 promoter methylation and are thought to arise from sessile serrated adenomas, termed the serrated neoplasia pathway. Although the presence of the BRAF V600E mutation is indicative of a sporadic cancer, up to 30% to 50% of colorectal carcinomas with MLH1 promoter hypermethylation will lack a BRAF mutation. We report the clinicopathologic and molecular features of MLH1-deficient colorectal carcinoma with wild-type BRAF and MLH1 promoter hypermethylation (referred to as MLH1-hypermethylated BRAF wild-type colorectal carcinoma, n=36) in comparison with MLH1-deficient BRAF-mutated colorectal carcinoma (n=113) and Lynch syndrome-associated colorectal carcinoma (n=36). KRAS mutations were identified in 31% of MLH1-hypermethylated BRAF wild-type colorectal carcinomas compared with 0% of MLH1-deficient BRAF-mutated colorectal carcinomas and 37% of Lynch syndrome-associated colorectal carcinomas. When a precursor polyp was identified, MLH1-hypermethylated BRAF wild-type colorectal carcinomas arose from precursor polyps resembling conventional tubular/tubulovillous adenomas in contrast to MLH1-deficient BRAF-mutated colorectal carcinomas, which arose from precursor sessile serrated adenomas (PMLH1-hypermethylated BRAF wild-type colorectal carcinoma and MLH1-deficient BRAF-mutated colorectal carcinoma had a predilection for the right colon compared with Lynch syndrome-associated colorectal carcinoma (86% vs. 92% vs. 49%, P0.05). In conclusion, our results indicate that MLH1-hypermethylated BRAF wild-type colorectal carcinomas can harbor KRAS mutations and arise from precursor polyps resembling conventional tubular/tubulovillous adenomas.

Parasite prevalence corresponds to host life history in a diverse assemblage of afrotropical birds and haemosporidian parasites.

Directory of Open Access Journals (Sweden)

Holly L Lutz

Full Text Available Avian host life history traits have been hypothesized to predict rates of infection by haemosporidian parasites. Using molecular techniques, we tested this hypothesis for parasites from three haemosporidian genera (Plasmodium, Haemoproteus, and Leucocytozoon collected from a diverse sampling of birds in northern Malawi. We found that host life history traits were significantly associated with parasitism rates by all three parasite genera. Nest type and nest location predicted infection probability for all three parasite genera, whereas flocking behavior is an important predictor of Plasmodium and Haemoproteus infection and habitat is an important predictor of Leucocytozoon infection. Parasite prevalence was 79.1% across all individuals sampled, higher than that reported for comparable studies from any other region of the world. Parasite diversity was also exceptionally high, with 248 parasite cytochrome b lineages identified from 152 host species. A large proportion of Plasmodium, Haemoproteus, and Leucocytozoon parasite DNA sequences identified in this study represent new, previously undocumented lineages (n = 201; 81% of total identified based on BLAST queries against the avian malaria database, MalAvi.

Use of the intestinal parasite community of Sigmodon hispidus as a biomonitor in terrestrial systems

International Nuclear Information System (INIS)

Faulkner, B.C.; Lochmiller, R.L.

1995-01-01

The goal of this study was to assess the potential usefulness of parasite communities of small mammals as an endpoint for community level risk assessment in terrestrial ecosystems. A total of 350 wild cotton rats (Sigmodon hispidus) were collected from a Superfund site in southwestern Oklahoma between fall 1993 and fall 1995. Three contaminated study sites, representing common petrochemical disposal methods and all containing complex mixtures of contaminants, including arsenic, lead, fluoride, phenols, and hydrocarbons, were monitored seasonally. Animals were collected and gastrointestinal contents were examined grossly and microscopically for helminths and coccidial parasites. All parasites were identified to species and enumerated so that measurable alterations of the parasite community structure could be established. The authors also sampled possible intermediate host communities concurrently with Sigmodon collections. Structural characteristics of the parasite communities were compared between replicated toxic and reference study sites

Mineral phosphate solubilization by wild type and radiation induced mutants of pantoea dispersa and pantoea terrae

International Nuclear Information System (INIS)

Murugesan, Senthilkumar; Lee, Young Keun; Kim, Jung Hun

2009-01-01

Three mineral phosphate solubilizing (MPS) bacteria where isolated from rhizosphere soil samples of common bean and weed plants. 16S rDNA analysis indicated that the isolate P2 and P3 are closely related to Pantoea dispersa while isolate P4 is closely related to Pantoea terrae. Islates P2 and P3 recorded 381.60 μg ml -1 of tricalcium phosphate (TCP) solubilization respectively on 3 days incubation. Isolate P4 recorded the TCP solubilization of 215.85 μg ml -1 and the pH was dropped to 4.44 on 24 h incubation. Further incubation of P4 sharply decreased the available phosphorous to 28.94 μg ml -1 and pH level was raised to 6.32. Gamma radiation induced mutagenesis was carried out at LD 99 dose of the wild type strains. The total of 14 mutant clones with enhanced MPS activity and 4 clones with decreased activity were selected based on solubilization index (SI) and phosphate solubilization assay. Mutant P2-M1 recorded the highest P-solubilizing potential among any other wild or mutnat clones by releasing 504.21 μg ml -1 of phosphorous i.e. 35% higher than its wild type by the end of day 5. A comparative evaluation of TCP solubilization by wild type isolates of Pantoea and their mutants, led to select three MPS mutant clones such as P2-M1, P3-M2 and P3-M4 with a potential to release >471.67 μg ml 1 of phosphorous from TCP. These over expressing mutant clones are considered as suitable candidates for biofertilization

Fitness of crop-wild hybrid sunflower under competitive conditions: implications for crop-to-wild introgression.

Science.gov (United States)

Mercer, Kristin L; Emry, D Jason; Snow, Allison A; Kost, Matthew A; Pace, Brian A; Alexander, Helen M

2014-01-01

Understanding the likelihood and extent of introgression of novel alleles in hybrid zones requires comparison of lifetime fitness of parents and hybrid progeny. However, fitness differences among cross types can vary depending on biotic conditions, thereby influencing introgression patterns. Based on past work, we predicted that increased competition would enhance introgression between cultivated and wild sunflower (Helianthus annuus) by reducing fitness advantages of wild plants. To test this prediction, we established a factorial field experiment in Kansas, USA where we monitored the fitness of four cross types (Wild, F1, F2, and BCw hybrids) under different levels of interspecific and intraspecific competition. Intraspecific manipulations consisted both of density of competitors and of frequency of crop-wild hybrids. We recorded emergence of overwintered seeds, survival to reproduction, and numbers of seeds produced per reproductive plant. We also calculated two compound fitness measures: seeds produced per emerged seedling and seeds produced per planted seed. Cross type and intraspecific competition affected emergence and survival to reproduction, respectively. Further, cross type interacted with competitive treatments to influence all other fitness traits. More intense competition treatments, especially related to density of intraspecific competitors, repeatedly reduced the fitness advantage of wild plants when considering seeds produced per reproductive plant and per emerged seedling, and F2 plants often became indistinguishable from the wilds. Wild fitness remained superior when seedling emergence was also considered as part of fitness, but the fitness of F2 hybrids relative to wild plants more than quadrupled with the addition of interspecific competitors and high densities of intraspecific competitors. Meanwhile, contrary to prediction, lower hybrid frequency reduced wild fitness advantage. These results emphasize the importance of taking a full life cycle

Fitness of crop-wild hybrid sunflower under competitive conditions: implications for crop-to-wild introgression.

Directory of Open Access Journals (Sweden)

Kristin L Mercer

Full Text Available Understanding the likelihood and extent of introgression of novel alleles in hybrid zones requires comparison of lifetime fitness of parents and hybrid progeny. However, fitness differences among cross types can vary depending on biotic conditions, thereby influencing introgression patterns. Based on past work, we predicted that increased competition would enhance introgression between cultivated and wild sunflower (Helianthus annuus by reducing fitness advantages of wild plants. To test this prediction, we established a factorial field experiment in Kansas, USA where we monitored the fitness of four cross types (Wild, F1, F2, and BCw hybrids under different levels of interspecific and intraspecific competition. Intraspecific manipulations consisted both of density of competitors and of frequency of crop-wild hybrids. We recorded emergence of overwintered seeds, survival to reproduction, and numbers of seeds produced per reproductive plant. We also calculated two compound fitness measures: seeds produced per emerged seedling and seeds produced per planted seed. Cross type and intraspecific competition affected emergence and survival to reproduction, respectively. Further, cross type interacted with competitive treatments to influence all other fitness traits. More intense competition treatments, especially related to density of intraspecific competitors, repeatedly reduced the fitness advantage of wild plants when considering seeds produced per reproductive plant and per emerged seedling, and F2 plants often became indistinguishable from the wilds. Wild fitness remained superior when seedling emergence was also considered as part of fitness, but the fitness of F2 hybrids relative to wild plants more than quadrupled with the addition of interspecific competitors and high densities of intraspecific competitors. Meanwhile, contrary to prediction, lower hybrid frequency reduced wild fitness advantage. These results emphasize the importance of taking

Fitness of Crop-Wild Hybrid Sunflower under Competitive Conditions: Implications for Crop-to-Wild Introgression

Science.gov (United States)

Mercer, Kristin L.; Emry, D. Jason; Snow, Allison A.; Kost, Matthew A.; Pace, Brian A.; Alexander, Helen M.

2014-01-01

Understanding the likelihood and extent of introgression of novel alleles in hybrid zones requires comparison of lifetime fitness of parents and hybrid progeny. However, fitness differences among cross types can vary depending on biotic conditions, thereby influencing introgression patterns. Based on past work, we predicted that increased competition would enhance introgression between cultivated and wild sunflower (Helianthus annuus) by reducing fitness advantages of wild plants. To test this prediction, we established a factorial field experiment in Kansas, USA where we monitored the fitness of four cross types (Wild, F1, F2, and BCw hybrids) under different levels of interspecific and intraspecific competition. Intraspecific manipulations consisted both of density of competitors and of frequency of crop-wild hybrids. We recorded emergence of overwintered seeds, survival to reproduction, and numbers of seeds produced per reproductive plant. We also calculated two compound fitness measures: seeds produced per emerged seedling and seeds produced per planted seed. Cross type and intraspecific competition affected emergence and survival to reproduction, respectively. Further, cross type interacted with competitive treatments to influence all other fitness traits. More intense competition treatments, especially related to density of intraspecific competitors, repeatedly reduced the fitness advantage of wild plants when considering seeds produced per reproductive plant and per emerged seedling, and F2 plants often became indistinguishable from the wilds. Wild fitness remained superior when seedling emergence was also considered as part of fitness, but the fitness of F2 hybrids relative to wild plants more than quadrupled with the addition of interspecific competitors and high densities of intraspecific competitors. Meanwhile, contrary to prediction, lower hybrid frequency reduced wild fitness advantage. These results emphasize the importance of taking a full life cycle

The Plasmodium PI(4)K inhibitor KDU691 selectively inhibits dihydroartemisinin-pretreated Plasmodium falciparum ring-stage parasites.

Science.gov (United States)

Dembele, L; Ang, X; Chavchich, M; Bonamy, G M C; Selva, J J; Lim, M Yi-Xiu; Bodenreider, C; Yeung, B K S; Nosten, F; Russell, B M; Edstein, M D; Straimer, J; Fidock, D A; Diagana, T T; Bifani, P

2017-05-24

Malaria control and elimination are threatened by the emergence and spread of resistance to artemisinin-based combination therapies (ACTs). Experimental evidence suggests that when an artemisinin (ART)-sensitive (K13 wild-type) Plasmodium falciparum strain is exposed to ART derivatives such as dihydroartemisinin (DHA), a small population of the early ring-stage parasites can survive drug treatment by entering cell cycle arrest or dormancy. After drug removal, these parasites can resume growth. Dormancy has been hypothesized to be an adaptive physiological mechanism that has been linked to recrudescence of parasites after monotherapy with ART and, possibly contributes to ART resistance. Here, we evaluate the in vitro drug sensitivity profile of normally-developing P. falciparum ring stages and DHA-pretreated dormant rings (DP-rings) using a panel of antimalarial drugs, including the Plasmodium phosphatidylinositol-4-OH kinase (PI4K)-specific inhibitor KDU691. We report that while KDU691 shows no activity against rings, it is highly inhibitory against DP-rings; a drug effect opposite to that of ART. Moreover, we provide evidence that KDU691 also kills DP-rings of P. falciparum ART-resistant strains expressing mutant K13.

Integrated parasite management

DEFF Research Database (Denmark)

Clausen, Jesper Hedegaard; Madsen, Henry; Van, Phan Thi

2015-01-01

communities at risk through mass drug administration. However, we argue that treatment alone will not reduce the risk from eating infected fish and that sustainable effective control must adopt an integrated FZT control approach based on education, infrastructure improvements, and management practices...... that target critical control points in the aquaculture production cycle identified from a thorough understanding of FZT and host biology and epidemiology. We present recommendations for an integrated parasite management (IPM) program for aquaculture farms.......Fishborne zoonotic trematodes (FZT) are an emerging problem and there is now a consensus that, in addition to wild-caught fish, fish produced in aquaculture present a major food safety risk, especially in Southeast Asia where aquaculture is important economically. Current control programs target...

Mathematical model of the SOS response regulation in wild-type Escherichia coli

International Nuclear Information System (INIS)

Aksenov, S.V.

1997-01-01

Regulation of the SOS response in Escherichia coli, which is a set of inducible cellular reactions introduced after DNA damage, is due to specific interaction of LexA and RecA proteins. LexA protein is a common repressor of the genes of the SOS system, and RecA protein, once transiently activated by the so-called SOS-inducing signal, promotes LexA protein destruction. We have described the SOS regulation by means of differential equations with regard to LexA and RecA concentrations elsewhere. The 'input' function for model equations is the level of the SOS-inducing signal against time. Here we present a means for calculating the concentration of single-stranded DNA (SOS-inducing signal) as a function of time in wild-type cells after ultraviolet irradiation. With model equations one can simulate kinetic curves of SOS regulatory proteins after DNA damage to survey the SOS response kinetics. Simulation of LexA protein kinetics agrees with experimental data. We compare simulated LexA kinetic curves in wild-type and uνr - mutant bacteria, which is useful in investigating the way uνrABC-dependent excision repair modulates the SOS response kinetics. Possible applications of the model to investigating various aspects of the SOS induction are discussed

Repetitive elements in parasitic protozoa

Directory of Open Access Journals (Sweden)

Clayton Christine

2010-05-01

Full Text Available Abstract A recent paper published in BMC Genomics suggests that retrotransposition may be active in the human gut parasite Entamoeba histolytica. This adds to our knowledge of the various types of repetitive elements in parasitic protists and the potential influence of such elements on pathogenicity. See research article http://www.biomedcentral.com/1471-2164/11/321

Prevalence and diversity of Babesia, Hepatozoon, Ehrlichia, and Bartonella in wild and domestic carnivores from Zambia, Africa.

Science.gov (United States)

Williams, Brianna M; Berentsen, Are; Shock, Barbara C; Teixiera, Maria; Dunbar, Michael R; Becker, Matthew S; Yabsley, Michael J

2014-03-01

A molecular survey was conducted for several hemoparasites of domestic dogs and three species of wild carnivores from two sites in Zambia. Three Babesia spp. were detected including Babesia felis and Babesia leo in lions (Panthera leo) and a Babesia sp. (similar to Babesia lengau) in spotted hyenas (Crocuta crocuta) and a single lion. All wild dogs (Lycaon pictus) and domestic dogs were negative for Babesia. High prevalences for Hepatozoon were noted in all three wild carnivores (38-61%) and in domestic dogs (13%). Significantly higher prevalences were noted in hyenas and wild dogs compared with domestic dogs and lions. All carnivores were PCR negative for Ehrlichia canis, Ehrlichia ewingii, and Bartonella spp. Overall, high prevalences and diversity of Babesia and Hepatozoon were noted in wild carnivores from Zambia. This study is the first molecular characterization of Babesia from any hyena species and is the first report of a Babesia sp. closely related to B. lengau, a parasite previously only reported from cheetahs (Acinonyx jubatus), in lions and hyenas. Although usually benign in wild carnivores, these hemoparasites can be pathogenic under certain circumstances. Importantly, data on vectors for these parasites are lacking, so studies are needed to identify vectors as well as determine transmission routes, infection dynamics, and host specificity of these hemoparasites in wildlife in Africa and also the risk of transmission between domestic animals and wildlife.

A Trypanosoma brucei kinesin heavy chain promotes parasite growth by triggering host arginase activity.

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Géraldine De Muylder

2013-10-01

Full Text Available In order to promote infection, the blood-borne parasite Trypanosoma brucei releases factors that upregulate arginase expression and activity in myeloid cells.By screening a cDNA library of T. brucei with an antibody neutralizing the arginase-inducing activity of parasite released factors, we identified a Kinesin Heavy Chain isoform, termed TbKHC1, as responsible for this effect. Following interaction with mouse myeloid cells, natural or recombinant TbKHC1 triggered SIGN-R1 receptor-dependent induction of IL-10 production, resulting in arginase-1 activation concomitant with reduction of nitric oxide (NO synthase activity. This TbKHC1 activity was IL-4Rα-independent and did not mirror M2 activation of myeloid cells. As compared to wild-type T. brucei, infection by TbKHC1 KO parasites was characterized by strongly reduced parasitaemia and prolonged host survival time. By treating infected mice with ornithine or with NO synthase inhibitor, we observed that during the first wave of parasitaemia the parasite growth-promoting effect of TbKHC1-mediated arginase activation resulted more from increased polyamine production than from reduction of NO synthesis. In late stage infection, TbKHC1-mediated reduction of NO synthesis appeared to contribute to liver damage linked to shortening of host survival time.A kinesin heavy chain released by T. brucei induces IL-10 and arginase-1 through SIGN-R1 signaling in myeloid cells, which promotes early trypanosome growth and favors parasite settlement in the host. Moreover, in the late stage of infection, the inhibition of NO synthesis by TbKHC1 contributes to liver pathogenicity.

A synoptic overview of golden jackal parasites reveals high diversity of species.

Science.gov (United States)

Gherman, Călin Mircea; Mihalca, Andrei Daniel

2017-09-15

The golden jackal (Canis aureus) is a species under significant and fast geographic expansion. Various parasites are known from golden jackals across their geographic range, and certain groups can be spread during their expansion, increasing the risk of cross-infection with other carnivores or even humans. The current list of the golden jackal parasites includes 194 species and was compiled on the basis of an extensive literature search published from historical times until April 2017, and is shown herein in synoptic tables followed by critical comments of the various findings. This large variety of parasites is related to the extensive geographic range, territorial mobility and a very unselective diet. The vast majority of these parasites are shared with domestic dogs or cats. The zoonotic potential is the most important aspect of species reported in the golden jackal, some of them, such as Echinococcus spp., hookworms, Toxocara spp., or Trichinella spp., having a great public health impact. Our review brings overwhelming evidence on the importance of Canis aureus as a wild reservoir of human and animal parasites.

Observations on the helminth parasites of wild and cultured tilapia in ...

African Journals Online (AJOL)

A total of 449 specimen of Tilapia comprising Tilapia nilotica (Oreochromis), Tilapia zilli and Tilapia galilea (Sarotherodon) collected from the Federal and State Fish ponds, Okigwe and from the Imo River were examined for helminth infections. Out of these, only 5 (1.1%) fish were infected. These came from the wild. Tilapia ...

The plant-parasitic nematode collections of RRIP: The realization of an ISTC project

Science.gov (United States)

Plant-parasitic nematodes are important pests of agricultural and wild plants throughout Russia and the world. The best strategy for management of nematode damage is an integrated approach to the problem: i.e., the use of agrotechnological approaches (crop rotation, soil amendments, etc.), reasonabl...

Clavulanic acid production by the MMS 150 mutant obtained from wild type Streptomyces clavuligerus ATCC 27064

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Eliton da Silva Vasconcelos

2013-12-01

Full Text Available Clavulanic acid (CA is a powerful inhibitor of the beta-lactamases, enzymes produced by bacteria resistants to penicillin and cefalosporin. This molecule is produced industrially by strains of Streptomyces clavuligerus in complex media which carbon and nitrogen resources are supplied by inexpensive compounds still providing high productivity. The genetic production improvement using physical and chemical mutagenic agents is an important strategy in programs of industrial production development of bioactive metabolites. However, parental strains are susceptible to loss of their original productivity due genetic instability phenomenona. In this work, some S. clavuligerus mutant strains obtained by treatment with UV light and with MMS are compared with the wild type (Streptomyces clavuligerus ATCC 27064. The results indicated that the random mutations originated some strains with different phenotypes, most divergent demonstrated by the mutants strains named AC116, MMS 150 and MMS 54, that exhibited lack of pigmentation in their mature spores. Also, the strain MMS 150 presented a larger production of CA when cultivated in semi-synthetics media. Using other media, the wild type strain obtained a larger CA production. Besides, using the modifed complex media the MMS 150 strain showed changes in its lipolitic activity and a larger production of CA. The studies also allowed finding the best conditions for a lipase activity exhibited by wild type S. clavuligerus and the MMS150 mutant.

Clavulanic acid production by the MMS 150 mutant obtained from wild type Streptomyces clavuligerus ATCC 27064.

Science.gov (United States)

da Silva Vasconcelos, Eliton; de Lima, Vanderlei Aparecido; Goto, Leandro Seiji; Cruz-Hernández, Isara Lourdes; Hokka, Carlos Osamu

2013-12-01

Clavulanic acid (CA) is a powerful inhibitor of the beta-lactamases, enzymes produced by bacteria resistants to penicillin and cefalosporin. This molecule is produced industrially by strains of Streptomyces clavuligerus in complex media which carbon and nitrogen resources are supplied by inexpensive compounds still providing high productivity. The genetic production improvement using physical and chemical mutagenic agents is an important strategy in programs of industrial production development of bioactive metabolites. However, parental strains are susceptible to loss of their original productivity due genetic instability phenomenona. In this work, some S. clavuligerus mutant strains obtained by treatment with UV light and with MMS are compared with the wild type (Streptomyces clavuligerus ATCC 27064). The results indicated that the random mutations originated some strains with different phenotypes, most divergent demonstrated by the mutants strains named AC116, MMS 150 and MMS 54, that exhibited lack of pigmentation in their mature spores. Also, the strain MMS 150 presented a larger production of CA when cultivated in semi-synthetics media. Using other media, the wild type strain obtained a larger CA production. Besides, using the modifed complex media the MMS 150 strain showed changes in its lipolitic activity and a larger production of CA. The studies also allowed finding the best conditions for a lipase activity exhibited by wild type S. clavuligerus and the MMS150 mutant.

Positive Selection of Plasmodium falciparum Parasites With Multiple var2csa-Type PfEMP1 Genes During the Course of Infection in Pregnant Women

Science.gov (United States)

Salanti, Ali; Lavstsen, Thomas; Nielsen, Morten A.; Theander, Thor G.; Leke, Rose G. F.; Lo, Yeung Y.; Bobbili, Naveen; Arnot, David E.; Taylor, Diane W.

2011-01-01

Placental malaria infections are caused by Plasmodium falciparum–infected red blood cells sequestering in the placenta by binding to chondroitin sulfate A, mediated by VAR2CSA, a variant of the PfEMP1 family of adhesion antigens. Recent studies have shown that many P. falciparum genomes have multiple genes coding for different VAR2CSA proteins, and parasites with >1 var2csa gene appear to be more common in pregnant women with placental malaria than in nonpregnant individuals. We present evidence that, in pregnant women, parasites containing multiple var2csa-type genes possess a selective advantage over parasites with a single var2csa gene. Accumulation of parasites with multiple copies of the var2csa gene during the course of pregnancy was also correlated with the development of antibodies involved in blocking VAR2CSA adhesion. The data suggest that multiplicity of var2csa-type genes enables P. falciparum parasites to persist for a longer period of time during placental infections, probably because of their greater capacity for antigenic variation and evasion of variant-specific immune responses. PMID:21592998

Craniofacial Statistical Deformation Models of Wild-type mice and Crouzon mice

DEFF Research Database (Denmark)

Ólafsdóttir, Hildur; Darvann, Tron Andre; Ersbøll, Bjarne Kjær

2007-01-01

Crouzon syndrome is characterised by the premature fusion of cranial sutures and synchondroses leading to craniofacial growth disturbances. The gene causing the syndrome was discovered approximately a decade ago and recently the first mouse model of the syndrome was generated. In this study, a set...... of Micro CT scannings of the heads of wild-type (normal) mice and Crouzon mice were investigated. Statistical deformation models were built to assess the anatomical differences between the groups, as well as the within-group anatomical variation. Following the approach by Rueckert et al. we built an atlas...

Phosphorylated EGFR expression may predict outcome of EGFR-TKIs therapy for the advanced NSCLC patients with wild-type EGFR

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Wang Fen

2012-08-01

Full Text Available Abstract Background EGFR mutation is a strong predictive factor of EGFR-TKIs therapy. However, at least 10% of patients with EGFR wild-type are responsive to TKIs, suggesting that other determinants of outcome besides EGFR mutation might exist. We hypothesized that activation of phosphorylated EGFR could be a potential predictive biomarker to EGFR-TKIs treatment among patients in wild-type EGFR. Method Total of 205 stage IIIb and IV NSCLC patients, tissue samples of whom were available for molecular analysis, were enrolled in this study. The phosphorylation of EGFR at tyrosine 1068 (pTyr1068 and 1173 (pTyr1173 were assessed by immunohistochemistry, and EGFR mutations were detected by denaturing high performance liquid chromatograph (DHPLC. Results Among 205 patients assessable for EGFR mutation and phosphorylation analysis, 92 (44.9% were EGFR mutant and 165 patients (57.6% had pTyr1173 expression. Superior progression-free survival (PFS was seen after EGFR-TKIs therapy in patients with pTyr1068 expression compared to pTyr1068 negative ones (median PFS 7.0 months vs. 1.2 months, P P = 0.016. In subgroup of patients with wild-type EGFR, pTyr1068 expression positive ones had a significantly prolonged PFS (4.2 months vs.1.2 months P  Conclusion pTyr1068 may be a predictive biomarker for screening the population for clinical response to EGFR-TKIs treatment; especially for patients with wild-type EGFR.

Personality differences in two minnow populations that differ in their parasitism and predation risk

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Raine eKortet

2015-02-01

Full Text Available Animals are often individually consistent in their behavior, not only over time, but also across different functional contexts. Recent research has focused on phenotypic and evolutionary mechanisms explaining such personality differences through selection. Parasitism and predation induce important mortality and fitness costs, and are thus the main candidates to create and maintain personality differences in the wild. Here, we present data on the behavioral consistency of the Eurasian minnow (Phoxinus phoxinus from two populations that live in different tributaries of the same river, but whose ecological environment differs fundamentally with regard to predation and parasitism. We experimentally demonstrate that minnow in both study populations are consistent in their boldness and activity. However, the two study populations differ notably: in the high predation and parasitism risk population fish show higher mean boldness, but tend to be less active than fish in low predation and parasitism risk population. Parasite (Diplostomum phoxini load was negatively, but not statistically significantly, associated with fish activity level. Our study suggests that parasitism and predation are likely important agents in the ecology and evolution of animal personalities.

Parasites of edible land snails in Edo State, Nigeria

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Igbinosa I. B.

2016-12-01

Full Text Available Land snails are sources of protein to man and are hosts to a number of parasites. It is imperative that the roles of the snail hosts and parasites are clearly defined. Before then however, the parasites of the different land snails collected in any locality should be identified. Land snails were collected in the wild in both dry and wet seasons. The internal organs and the faeces were examined for the presence of parasite. In the rainy season of 2015, a total of 272 snails were collected across four major towns (Benin, Uromi, Ekpoma and Auchi in Edo State, Nigeria, while in the dry season, fewer snails (n=91 were handpicked. The snail species seen are: Achatina achatina (Linnaeus, 1758, Achatina fulica (Férussac, 1821, Acharchatina marginata (Swainson, 1982, Limicolaria aurora (Jay, 1839, L. flammea (Müller, 1774 and Limicolariopsis spp. The larvae of Strongyloides stercoralis were isolated from the various snail species with overall prevalence of 54.04 %. Snails positive with Alaria mesocercariae were L. aurora, L. flammea and Limicolariopsis spp. Additionally, few L. flammea were positive of the cercariae of Drocoelium dedriticum. Meanwhile, some samples of A. fulica harboured larvae of Angiostrongylus cantonesis, sporocysts of Fasciola gigantica and Schistosoma mansoni. Therefore, these edible snails could pose serious health hazard to man and animals by serving as a possible alternative parasite transmission route.

The Plasmodium serine-type SERA proteases display distinct expression patterns and non-essential in vivo roles during life cycle progression of the malaria parasite.

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Putrianti, Elyzana D; Schmidt-Christensen, Anja; Arnold, Iris; Heussler, Volker T; Matuschewski, Kai; Silvie, Olivier

2010-06-01

Parasite proteases play key roles in several fundamental steps of the Plasmodium life cycle, including haemoglobin degradation, host cell invasion and parasite egress. Plasmodium exit from infected host cells appears to be mediated by a class of papain-like cysteine proteases called 'serine repeat antigens' (SERAs). A SERA subfamily, represented by Plasmodium falciparum SERA5, contains an atypical active site serine residue instead of a catalytic cysteine. Members of this SERAser subfamily are abundantly expressed in asexual blood stages, rendering them attractive drug and vaccine targets. In this study, we show by antibody localization and in vivo fluorescent tagging with the red fluorescent protein mCherry that the two P. berghei serine-type family members, PbSERA1 and PbSERA2, display differential expression towards the final stages of merozoite formation. Via targeted gene replacement, we generated single and double gene knockouts of the P. berghei SERAser genes. These loss-of-function lines progressed normally through the parasite life cycle, suggesting a specialized, non-vital role for serine-type SERAs in vivo. Parasites lacking PbSERAser showed increased expression of the cysteine-type PbSERA3. Compensatory mechanisms between distinct SERA subfamilies may thus explain the absence of phenotypical defect in SERAser disruptants, and challenge the suitability to develop potent antimalarial drugs based on specific inhibitors of Plasmodium serine-type SERAs.

Sarcocystosis of chital-dhole: conditions for evolutionary stability of a predator parasite mutualism

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Watve Milind G

2005-02-01

Full Text Available Abstract Background For parasites with a predator-prey life cycle, the completion of the life cycle often depends on consumption of parasitized prey by the predator. In the case of such parasite species the predator and the parasite have common interests and therefore a mutualistic relationship is possible. Some evidence of a predator-parasite mutualism was reported from spotted deer or chital (Axix axis as a prey species, dhole or Indian wild-dog (Cuon alpinus as the predator and a protozoan (Sarcocystis axicuonis as the parasite. We examine here, with the help of a model, the ecological conditions necessary for the evolution and stability of such a mutualistic relationship. A two – level game theory model was designed in which the payoff of a parasite is decided not only by alternative parasite strategies but also by alternative host strategies and vice versa. Conditions for ESS were examined. Results A tolerant predator strategy and a low or moderately virulent parasite strategy which together constitute mutualism are stable only at a high frequency of recycling of parasite and a substantial prey – capture benefit to the predator. Unlike the preliminary expectation, parasite will not evolve towards reduced virulence, but reach an optimum moderate level of virulence. Conclusion The available data on the behavioral ecology of dhole and chital suggest that they are likely to meet the stability criteria and therefore a predator-parasite mutualism can be stable in this system. The model also points out the gaps in the current data and could help directing further empirical work.

Molecular characterization of muscle-parasitizing didymozoid from a chub mackerel, Scomber japonicus.

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Abe, Niichiro; Okamoto, Mitsuru

2015-09-01

Didymozoids found in the muscles of marine fish are almost always damaged because they are usually found after being sliced. Therefore, identifying muscle-parasitizing didymozoids is difficult because of the difficulty in collecting non-damaged worms and observing their organs as key points for morphological identification. Moreover, muscle-parasitizing didymozoids are not easily found because they parasitize at the trunk muscles. Therefore, muscle-parasitizing didymozoid classification has not progressed because there are few opportunities to detect them. Our recent report was the first to describe the usefulness of sequencing analysis for discrimination among muscle-parasitizing didymozoids. Recently, we found a didymozoid in the trunk muscle of a chub mackerel Scomber japonicus. The present study genetically compares the present isolate with other muscle-parasitizing didymozoids. The present isolate differs markedly from the previously unidentified didymozoid from an Atlantic mackerel S. scombrus by phylogenetic analysis of 18S rDNA. It also differs from other muscle-parasitizing didymozoids from other host species based on phylogenetic analyses of 18S, 28S rDNAs, and coxI loci. These results suggest that sequencing analysis is useful for the discrimination of muscle-parasitizing didymozoids. Combining the present data with earlier data for sequencing analysis, muscle-parasitizing didymozoids from seven marine fish species were classified as seven species. We proposed appellations for six distinct muscle-parasitizing didymozoids for future analysis: sweetlips fish type from Diagramma pictum and Plectorhinchus cinctus, red sea bream type from Pagrus major, flying fish type from Cypselurus heterurus, Atlantic mackerel type from Scomber scombrus, chub mackerel type from S. japonicus, and purple rockcod type from Epinephelus cyanopodus.

Parasite Removal, but Not Herbivory, Deters Future Parasite Attachment on Tomato

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Tjiurutue, Muvari Connie; Palmer-Young, Evan C.; Adler, Lynn S.

2016-01-01

Plants face many antagonistic interactions that occur sequentially. Often, plants employ defense strategies in response to the initial damage that are highly specific and can affect interactions with subsequent antagonists. In addition to herbivores and pathogens, plants face attacks by parasitic plants, but we know little about how prior herbivory compared to prior parasite attachment affects subsequent host interactions. If host plants can respond adaptively to these different damage types, we predict that prior parasitism would have a greater deterrent effect on subsequent parasites than would prior herbivory. To test the effects of prior parasitism and prior herbivory on subsequent parasitic dodder (Cuscuta spp.) preference, we conducted two separate greenhouse studies with tomato hosts (Solanum lycopersicum). In the first experiment, we tested the effects of previous dodder attachment on subsequent dodder preference on tomato hosts using three treatments: control plants that had no previous dodder attachment; dodder-removed plants that had an initial dodder seedling attached, removed and left in the same pot to simulate parasite death; and dodder-continuous plants with an initial dodder seedling that remained attached. In the second experiment, we tested the effects of previous caterpillar damage (Spodoptera exigua) and mechanical damage on future dodder attachment on tomato hosts. Dodder attached most slowly to tomato hosts that had dodder plants previously attached and then removed, compared to control plants or plants with continuous dodder attachment. In contrast, herbivory did not affect subsequent dodder attachment rate. These results indicate that dodder preference depended on the identity and the outcome of the initial attack, suggesting that early-season interactions have the potential for profound impacts on subsequent community dynamics. PMID:27529694

Parasite Removal, but Not Herbivory, Deters Future Parasite Attachment on Tomato.

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Muvari Connie Tjiurutue

Full Text Available Plants face many antagonistic interactions that occur sequentially. Often, plants employ defense strategies in response to the initial damage that are highly specific and can affect interactions with subsequent antagonists. In addition to herbivores and pathogens, plants face attacks by parasitic plants, but we know little about how prior herbivory compared to prior parasite attachment affects subsequent host interactions. If host plants can respond adaptively to these different damage types, we predict that prior parasitism would have a greater deterrent effect on subsequent parasites than would prior herbivory. To test the effects of prior parasitism and prior herbivory on subsequent parasitic dodder (Cuscuta spp. preference, we conducted two separate greenhouse studies with tomato hosts (Solanum lycopersicum. In the first experiment, we tested the effects of previous dodder attachment on subsequent dodder preference on tomato hosts using three treatments: control plants that had no previous dodder attachment; dodder-removed plants that had an initial dodder seedling attached, removed and left in the same pot to simulate parasite death; and dodder-continuous plants with an initial dodder seedling that remained attached. In the second experiment, we tested the effects of previous caterpillar damage (Spodoptera exigua and mechanical damage on future dodder attachment on tomato hosts. Dodder attached most slowly to tomato hosts that had dodder plants previously attached and then removed, compared to control plants or plants with continuous dodder attachment. In contrast, herbivory did not affect subsequent dodder attachment rate. These results indicate that dodder preference depended on the identity and the outcome of the initial attack, suggesting that early-season interactions have the potential for profound impacts on subsequent community dynamics.

Differentiation between probiotic and wild-type Bacillus cereus isolates by antibiotic susceptibility test and Fourier transform infrared spectroscopy (FT-IR).

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Mietke, Henriette; Beer, W; Schleif, Julia; Schabert, G; Reissbrodt, R

2010-05-30

Animal feed often contains probiotic Bacillus strains used as feed additives. Spores of the non-pathogenic B. cereus var. toyoi (product name Toyocerin) are used. Distinguishing between toxic wild-type Bacillus cereus strains and this probiotic strain is essential for evaluating the quality and risk of feed. Bacillus cereus CIP 5832 (product name Paciflor was used as probiotic strain until 2001. The properties of the two probiotic strains are quite similar. Differentiating between probiotic strains and wild-type B. cereus strains is not easy. ss-lactam antibiotics such as penicillin and cefamandole exhibit an inhibition zone in the agar diffusion test of probiotic B. cereus strains which are not seen for wild-type strains. Therefore, performing the agar diffusion test first may make sense before FT-IR testing. When randomly checking these strains by Fourier transform infrared spectroscopy (FT-IR), the probiotic B. cereus strains were separated from wild-type B. cereus/B. thuringiensis/B. mycoides/B. weihenstephanensis strains by means of hierarchical cluster analysis. The discriminatory information was contained in the spectral windows 3000-2800 cm(-1) ("fatty acid region"), 1200-900 cm(-1) ("carbohydrate region") and 900-700 cm(-1) ("fingerprint region"). It is concluded that FT-IR spectroscopy can be used for the rapid quality control and risk analysis of animal feed containing probiotic B. cereus strains. (c) 2010 Elsevier B.V. All rights reserved.

Glucocorticoid-regulated and constitutive trafficking of proteolytically processed cell surface-associated glycoproteins in wild type and variant rat hepatoma cells

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Amacher, S.L.; Goodman, L.J.; Bravo, D.A.; Wong, K.Y.; Goldfine, I.D.; Hawley, D.M.; Firestone, G.L.

1989-01-01

Glucocorticoids regulate the trafficking of mouse mammary tumor virus (MMTV) glycoproteins to the cell surface in the rat hepatoma cell line M1.54, but not in the immunoselected sorting variant CR4. To compare the localization of MMTV glycoproteins to another proteolytically processed glycoprotein, both wild type M1.54 cells and variant CR4 cells were transfected with a human insulin receptor (hIR) expression vector, pRSVhIR. The production of cell surface hIR was monitored in dexamethasone-treated and -untreated wild type M1.54 and variant CR4 cells by indirect immunofluorescence, direct plasma membrane immunoprecipitation, and by [125I] insulin binding. In both wild type and variant rat hepatoma cells, hIR were localized at the cell surface in the presence or in the absence of 1 microM dexamethasone. In contrast, the glucocorticoid-regulated trafficking of cell surface MMTV glycoproteins occurred only in wild type M1.54 cells. We conclude that the hIR, which undergoes posttranslational processing reactions similar to MMTV glycoproteins, does not require glucocorticoids to be transported to the plasma membrane and is representative of a subset of cell surface glycoproteins whose trafficking is constitutive in rat hepatoma cells. Thus, MMTV glycoproteins and hIR provide specific cell surface markers to characterize the glucocorticoid-regulated and constitutive sorting pathways

Energetic cost of bot fly parasitism in free-ranging eastern chipmunks.

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Careau, Vincent; Thomas, Donald W; Humphries, Murray M

2010-02-01

The energy and nutrient demands of parasites on their hosts are frequently invoked as an explanation for negative impacts of parasitism on host survival and reproductive success. Although cuterebrid bot flies are among the physically largest and most-studied insect parasites of mammals, the only study conducted on metabolic consequences of bot fly parasitism revealed a surprisingly small effect of bot flies on host metabolism. Here we test the prediction that bot fly parasitism increases the resting metabolic rate (RMR) of free-ranging eastern chipmunks (Tamias striatus), particularly in juveniles who have not previously encountered parasites and have to allocate energy to growth. We found no effect of bot fly parasitism on adults. In juveniles, however, we found that RMR strongly increased with the number of bot fly larvae hosted. For a subset of 12 juveniles during a year where parasite prevalence was particularly high, we also compared the RMR before versus during the peak of bot fly prevalence, allowing each individual to act as its own control. Each bot fly larva resulted in a approximately 7.6% increase in the RMR of its host while reducing juvenile growth rates. Finally, bot fly parasitism at the juvenile stage was positively correlated with adult stage RMR, suggesting persistent effects of bot flies on RMR. This study is the first to show an important effect of bot fly parasitism on the metabolism and growth of a wild mammal. Our work highlights the importance of studying cost of parasitism over multiple years in natural settings, as negative effects on hosts are more likely to emerge in periods of high energetic demand (e.g. growing juveniles) and/or in harsh environmental conditions (e.g. low food availability).

Identification of parasitic communities within European ticks using next-generation sequencing.

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Sarah Bonnet

2014-03-01

Full Text Available Risk assessment of tick-borne and zoonotic disease emergence necessitates sound knowledge of the particular microorganisms circulating within the communities of these major vectors. Assessment of pathogens carried by wild ticks must be performed without a priori, to allow for the detection of new or unexpected agents.We evaluated the potential of Next-Generation Sequencing techniques (NGS to produce an inventory of parasites carried by questing ticks. Sequences corresponding to parasites from two distinct genera were recovered in Ixodes ricinus ticks collected in Eastern France: Babesia spp. and Theileria spp. Four Babesia species were identified, three of which were zoonotic: B. divergens, Babesia sp. EU1 and B. microti; and one which infects cattle, B. major. This is the first time that these last two species have been identified in France. This approach also identified new sequences corresponding to as-yet unknown organisms similar to tropical Theileria species.Our findings demonstrate the capability of NGS to produce an inventory of live tick-borne parasites, which could potentially be transmitted by the ticks, and uncovers unexpected parasites in Western Europe.

First report of a Mephitidae (Mammalia: Carnivora naturally infected by parasites of the genus Physaloptera (Rudolphi, 1918 (Spirurida: Physalopteridae

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Gregório Correa Guimarães

2015-02-01

Full Text Available Wild animals may be regarded as reservoirs of several parasite species. The occurrence of certain parasitic agents may provide significant information on host’s ecology and behavior and its trophic relations. Thus, this study aimed to determine the parasitic fauna of wild animals from southern Minas Gerais within the period from January to December 2011. A cross-sectional study was conducted with a convenience sample consisting of the dead bodies of two run over animals, which were rescued from highways and transported to the Laboratory of Animal Anatomy of the Federal University of Lavras (UFLA. The specimens were inspected to verify the presence of ectoparasites and, then, dissected to resume gastrointestinal content and detect helminths. No ectoparasites were identified in the two animals, both belonging to the species Conepatus semistriatus (striped hog-nosed skunk, but the presence of helminths belonging to the genus Physaloptera was identified in the stomach of one specimen.

First report of a Mephitidae (Mammalia: Carnivora naturally infected by parasites of the genus Physaloptera (Rudolphi, 1918 (Spirurida: Physalopteridae

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Gregório Corrêa Guimarães

2015-05-01

Full Text Available Wild animals may be regarded as reservoirs of several parasite species. The occurrence of certain parasitic agents may provide significant information on host’s ecology and behavior and its trophic relations. Thus, this study aimed to determine the parasitic fauna of wild animals from southern Minas Gerais within the period from January to December 2011. A cross-sectional study was conducted with a convenience sample consisting of the dead bodies of two run over animals, which were rescued from highways and transported to the Laboratory of Animal Anatomy of the Federal University of Lavras (UFLA. The specimens were inspected to verify the presence of ectoparasites and, then, dissected to resume gastrointestinal content and detect helminths. No ectoparasites were identified in the two animals, both belonging to the species Conepatus semistriatus (striped hog-nosed skunk, but the presence of helminths belonging to the genus Physaloptera was identified in the stomach of one specimen.

Parasitic Apologies

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Galatolo, Renata; Ursi, Biagio; Bongelli, Ramona

2016-01-01

The action of apologizing can be accomplished as the main business of the interaction or incidentally while participants are doing something else. We refer to these apologies as "parasitic apologies," because they are produced "en passant" (Schegloff, 2007), and focus our analysis on this type of apology occurring at the…

Genome Sequences of Three Vaccine Strains and Two Wild-Type Canine Distemper Virus Strains from a Recent Disease Outbreak in South Africa.

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Loots, Angelika K; Du Plessis, Morné; Dalton, Desiré Lee; Mitchell, Emily; Venter, Estelle H

2017-07-06

Canine distemper virus causes global multihost infectious disease. This report details complete genome sequences of three vaccine and two new wild-type strains. The wild-type strains belong to the South African lineage, and all three vaccine strains to the America 1 lineage. This constitutes the first genomic sequences of this virus from South Africa. Copyright © 2017 Loots et al.

Physiological Correlates of Multiple Parasitic Infections in Side-Blotched Lizards.

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Spence, Austin R; Durso, Andrew M; Smith, Geoffrey D; Skinner, Heather M; French, Susannah S

We investigated the presence of ectoparasites and hemoparasites in side-blotched lizards (Uta stansburiana) across a large part of their range and measured how parasitic infection related to several key physiological indicators of health. Blood samples were collected from 132 lizards from central Arizona, southern Utah, and eastern Oregon. Hemoparasites were found in 22 individuals (3.2% prevalence in Arizona, 19.1% in Utah, and 6.3% in Oregon), and ectoparasites were found on 51 individuals (56.3% prevalence in Arizona, 56.1% in Utah, and 6.7% in Oregon), with 11 individuals infected with both. Hemoparasites and ectoparasites were found in all three states. Immunocompetence was higher in individuals infected with both hemoparasites and ectoparasites. Body condition, glucocorticoid levels, and reproductive investment were not related to infection status. Our study provides evidence that parasitic infection is associated with an active immune system in wild reptiles but may not impose other costs usually associated with parasites.

One Health: parasites and beyond.

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Blake, Damer P; Betson, Martha

2017-01-01

The field of parasitism is broad, encompassing relationships between organisms where one benefits at the expense of another. Traditionally the discipline focuses on eukaryotes, with the study of bacteria and viruses complementary but distinct. Nonetheless, parasites vary in size and complexity from single celled protozoa, to enormous plants like those in the genus Rafflesia. Lifecycles range from obligate intracellular to extensive exoparasitism. Examples of parasites include high-profile medical and zoonotic pathogens such as Plasmodium, veterinary pathogens of wild and captive animals and many of the agents which cause neglected tropical diseases, stretching to parasites which infect plants and other parasites (e.g. Kikuchi et al. 2011; Hotez et al. 2014; Blake et al. 2015; Hemingway, 2015; Meekums et al. 2015; Sandlund et al. 2015). The breadth of parasitology has been matched by the variety of ways in which parasites are studied, drawing upon biological, chemical, molecular, epidemiological and other expertise. Despite such breadth bridging between disciplines has commonly been problematic, regardless of extensive encouragement from government agencies, peer audiences and funding bodies promoting multidisciplinary research. Now, progress in understanding and collaboration can benefit from establishment of the One Health concept (Zinsstag et al. 2012; Stark et al. 2015). One Health draws upon biological, environmental, medical, veterinary and social science disciplines in order to improve human, animal and environmental health, although it remains tantalizingly difficult to engage many relevant parties. For infectious diseases traditional divides have been exacerbated as the importance of wildlife reservoirs, climate change, food production systems and socio-economic diversity have been recognized but often not addressed in a multidisciplinary manner. In response the 2015 Autumn Symposium organized by the British Society for Parasitology (BSP; https

Characterization of two second-site mutations preventing wild type protein aggregation caused by a dominant negative PMA1 mutant.

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Pilar Eraso

Full Text Available The correct biogenesis and localization of Pma1 at the plasma membrane is essential for yeast growth. A subset of PMA1 mutations behave as dominant negative because they produce aberrantly folded proteins that form protein aggregates, which in turn provoke the aggregation of the wild type protein. One approach to understand this dominant negative effect is to identify second-site mutations able to suppress the dominant lethal phenotype caused by those mutant alleles. We isolated and characterized two intragenic second-site suppressors of the PMA1-D378T dominant negative mutation. We present here the analysis of these new mutations that are located along the amino-terminal half of the protein and include a missense mutation, L151F, and an in-frame 12bp deletion that eliminates four residues from Cys409 to Ala412. The results show that the suppressor mutations disrupt the interaction between the mutant and wild type enzymes, and this enables the wild type Pma1 to reach the plasma membrane.

Amastin Knockdown in Leishmania braziliensis Affects Parasite-Macrophage Interaction and Results in Impaired Viability of Intracellular Amastigotes.

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Rita Marcia Cardoso de Paiva

2015-12-01

Full Text Available Leishmaniasis, a human parasitic disease with manifestations ranging from cutaneous ulcerations to fatal visceral infection, is caused by several Leishmania species. These protozoan parasites replicate as extracellular, flagellated promastigotes in the gut of a sandfly vector and as amastigotes inside the parasitophorous vacuole of vertebrate host macrophages. Amastins are surface glycoproteins encoded by large gene families present in the genomes of several trypanosomatids and highly expressed in the intracellular amastigote stages of Trypanosoma cruzi and Leishmania spp. Here, we showed that the genome of L. braziliensis contains 52 amastin genes belonging to all four previously described amastin subfamilies and that the expression of members of all subfamilies is upregulated in L. braziliensis amastigotes. Although primary sequence alignments showed no homology to any known protein sequence, homology searches based on secondary structure predictions indicate that amastins are related to claudins, a group of proteins that are components of eukaryotic tight junction complexes. By knocking-down the expression of δ-amastins in L. braziliensis, their essential role during infection became evident. δ-amastin knockdown parasites showed impaired growth after in vitro infection of mouse macrophages and completely failed to produce infection when inoculated in BALB/c mice, an attenuated phenotype that was reverted by the re-expression of an RNAi-resistant amastin gene. Further highlighting their essential role in host-parasite interactions, electron microscopy analyses of macrophages infected with amastin knockdown parasites showed significant alterations in the tight contact that is normally observed between the surface of wild type amastigotes and the membrane of the parasitophorous vacuole.

Detection and differentiation of wild-type and vaccine strains of canine distemper virus by a duplex reverse transcription polymerase chain reaction.

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Dong, X Y; Li, W H; Zhu, J L; Liu, W J; Zhao, M Q; Luo, Y W; Chen, J D

2015-01-01

Canine distemper virus (CDV) is the cause of canine distemper (CD) which is a severe and highly contagious disease in dogs. In the present study, a duplex reverse transcription polymerase chain reaction (RT-PCR) method was developed for the detection and differentiation of wild-type and vaccine strains of CDV. Four primers were designed to detect and discriminate the two viruses by generating 638- and 781-bp cDNA products, respectively. Furthermore, the duplex RT-PCR method was used to detect 67 field samples suspected of CD from Guangdong province in China. Results showed that, 33 samples were to be wild-type-like. The duplex RT-PCR method exhibited high specificity and sensitivity which could be used to effectively detect and differentiate wild-type and vaccine CDV, indicating its use for clinical detection and epidemiological surveillance.

Comparative Study on Growth Performance of Transgenic (Over-Expressed OsNHX1 and Wild-Type Nipponbare under Different Salinity Regimes

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Nurul Kahrani ISHAK

2015-11-01

Full Text Available Transgenic Nipponbare which over-expressed a Na+/H+ antiporter gene OsNHX1 was used to compare its growth performance, water status and photosynthetic efficiency with its wild type under varying salinity regimes. Chlorophyll content, quantum yield and photosynthetic rate were measured to assess the impact of salinity stress on photosynthetic efficiency for transgenic and wild-type Nipponbare. Effects of salinity on water status and gas exchange to both lines were studied by measuring water use efficiency, instantaneous transpiration rate and stomatal conductance. Dry shoot weight and leaf area were determined after three months of growth to assess the impacts of salinity on the growth of those two lines. Our study showed that both lines were affected by salinity stress, however, the transgenic line showed higher photosynthetic efficiency, better utilization of water, and better growth due to low transpiration rate and stomatal conductance. Reduction of photosynthetic efficiency exhibited by the wild-type Nipponbare was correlated to its poor growth under salinity stress.

Transcriptional regulatory program in wild-type and retinoblastoma gene-deficient mouse embryonic fibroblasts during adipocyte differentiation

DEFF Research Database (Denmark)

Hakim-Weber, Robab; Krogsdam, Anne-M; Jørgensen, Claus

2011-01-01

Although many molecular regulators of adipogenesis have been identified a comprehensive catalogue of components is still missing. Recent studies showed that the retinoblastoma protein (pRb) was expressed in the cell cycle and late cellular differentiation phase during adipogenesis. To investigate...... this dual role of pRb in the early and late stages of adipogenesis we used microarrays to perform a comprehensive systems-level analysis of the common transcriptional program of the classic 3T3-L1 preadipocyte cell line, wild-type mouse embryonic fibroblasts (MEFs), and retinoblastoma gene-deficient MEFs...... of experimental data and computational analyses pinpointed a feedback-loop between Pparg and Foxo1.To analyze the effects of the retinoblastoma protein at the transcriptional level we chose a perturbated system (Rb-/- MEFs) for comparison to the transcriptional program of wild-type MEFs. Gene ontology analysis...

Origin of the human malaria parasite Plasmodium falciparum in gorillas.

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Liu, Weimin; Li, Yingying; Learn, Gerald H; Rudicell, Rebecca S; Robertson, Joel D; Keele, Brandon F; Ndjango, Jean-Bosco N; Sanz, Crickette M; Morgan, David B; Locatelli, Sabrina; Gonder, Mary K; Kranzusch, Philip J; Walsh, Peter D; Delaporte, Eric; Mpoudi-Ngole, Eitel; Georgiev, Alexander V; Muller, Martin N; Shaw, George M; Peeters, Martine; Sharp, Paul M; Rayner, Julian C; Hahn, Beatrice H

2010-09-23

Plasmodium falciparum is the most prevalent and lethal of the malaria parasites infecting humans, yet the origin and evolutionary history of this important pathogen remain controversial. Here we develop a single-genome amplification strategy to identify and characterize Plasmodium spp. DNA sequences in faecal samples from wild-living apes. Among nearly 3,000 specimens collected from field sites throughout central Africa, we found Plasmodium infection in chimpanzees (Pan troglodytes) and western gorillas (Gorilla gorilla), but not in eastern gorillas (Gorilla beringei) or bonobos (Pan paniscus). Ape plasmodial infections were highly prevalent, widely distributed and almost always made up of mixed parasite species. Analysis of more than 1,100 mitochondrial, apicoplast and nuclear gene sequences from chimpanzees and gorillas revealed that 99% grouped within one of six host-specific lineages representing distinct Plasmodium species within the subgenus Laverania. One of these from western gorillas comprised parasites that were nearly identical to P. falciparum. In phylogenetic analyses of full-length mitochondrial sequences, human P. falciparum formed a monophyletic lineage within the gorilla parasite radiation. These findings indicate that P. falciparum is of gorilla origin and not of chimpanzee, bonobo or ancient human origin.

Anti-tumor activity of high-dose EGFR tyrosine kinase inhibitor and sequential docetaxel in wild type EGFR non-small cell lung cancer cell nude mouse xenografts

OpenAIRE

Tang, Ning; Zhang, Qianqian; Fang, Shu; Han, Xiao; Wang, Zhehai

2016-01-01

Treatment of non-small-cell lung cancer (NSCLC) with wild-type epidermal growth factor receptor (EGFR) is still a challenge. This study explored antitumor activity of high-dose icotinib (an EGFR tyrosine kinase inhibitor) plus sequential docetaxel against wild-type EGFR NSCLC cells-generated nude mouse xenografts. Nude mice were subcutaneously injected with wild-type EGFR NSCLC A549 cells and divided into different groups for 3-week treatment. Tumor xenograft volumes were monitored and record...

Annotating and quantifying pri-miRNA transcripts using RNA-Seq data of wild type and serrate-1 globular stage embryos of Arabidopsis thaliana

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Daniel Lepe-Soltero

2017-12-01

Full Text Available The genome annotation for the model plant Arabidopsis thaliana does not include the primary transcripts from which MIRNAs are processed. Here we present and analyze the raw mRNA sequencing data from wild type and serrate-1 globular stage embryos of A. thaliana, ecotype Columbia. Because SERRATE is required for pri-miRNA processing, these precursors accumulate in serrate-1 mutants, facilitating their detection using standard RNA-Seq protocols. We first use the mapping of the RNA-Seq reads to the reference genome to annotate the potential primary transcripts of MIRNAs expressed in the embryo. We then quantify these pri-miRNAs in wild type and serrate-1 mutants. Finally, we use differential expression analysis to determine which are up-regulated in serrate-1 compared to wild type, to select the best candidates for bona fide pri-miRNAs expressed in the globular stage embryos. In addition, we analyze a previously published RNA-Seq dataset of wild type and dicer-like 1 mutant embryos at the globular stage [1]. Our data are interpreted and discussed in a separate article [2].

Annotating and quantifying pri-miRNA transcripts using RNA-Seq data of wild type and serrate-1 globular stage embryos of Arabidopsis thaliana.

Science.gov (United States)

Lepe-Soltero, Daniel; Armenta-Medina, Alma; Xiang, Daoquan; Datla, Raju; Gillmor, C Stewart; Abreu-Goodger, Cei

2017-12-01

The genome annotation for the model plant Arabidopsis thaliana does not include the primary transcripts from which MIRNAs are processed. Here we present and analyze the raw mRNA sequencing data from wild type and serrate-1 globular stage embryos of A. thaliana , ecotype Columbia. Because SERRATE is required for pri-miRNA processing, these precursors accumulate in serrate-1 mutants, facilitating their detection using standard RNA-Seq protocols. We first use the mapping of the RNA-Seq reads to the reference genome to annotate the potential primary transcripts of MIRNAs expressed in the embryo. We then quantify these pri-miRNAs in wild type and serrate-1 mutants. Finally, we use differential expression analysis to determine which are up-regulated in serrate-1 compared to wild type, to select the best candidates for bona fide pri-miRNAs expressed in the globular stage embryos. In addition, we analyze a previously published RNA-Seq dataset of wild type and dicer-like 1 mutant embryos at the globular stage [1]. Our data are interpreted and discussed in a separate article [2].

Temporal and demographic blood parasite dynamics in two free-ranging neotropical primates

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Gideon A. Erkenswick

2017-08-01

Full Text Available Parasite-host relationships are influenced by several factors intrinsic to hosts, such as social standing, group membership, sex, and age. However, in wild populations, temporal variation in parasite distributions and concomitant infections can alter these patterns. We used microscropy and molecular methods to screen for naturally occurring haemoparasitic infections in two Neotropical primate host populations, the saddleback (Leontocebus weddelli and emperor (Saguinus imperator tamarin, in the lowland tropical rainforests of southeastern Peru. Repeat sampling was conducted from known individuals over a three-year period to test for parasite-host and parasite-parasite associations. Three parasites were detected in L. weddelli including Trypanosoma minasense, Mansonella mariae, and Dipetalonema spp., while S. imperator only hosted the latter two. Temporal variation in prevalence was observed in T. minasense and Dipetalonema spp., confirming the necessity of a multi-year study to evaluate parasite-host relationships in this system. Although callitrichids display a distinct reproductive dominance hierarchy, characterized by single breeding females that typically mate polyandrously and can suppress the reproduction of subdominant females, logistic models did not identify sex or breeding status as determining factors in the presence of these parasites. However, age class had a positive effect on infection with M. mariae and T. minasense, and adults demonstrated higher parasite species richness than juveniles or sub-adults across both species. Body weight had a positive effect on the presence of Dipetalonema spp. The inclusion of co-infection variables in statistical models of parasite presence/absence data improved model fit for two of three parasites. This study verifies the importance and need for broad spectrum and long-term screening of parasite assemblages of natural host populations.

Genotype-temperature interaction in the regulation of development, growth, and morphometrics in wild-type, and growth-hormone transgenic coho salmon.

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Mare Lõhmus

2010-04-01

Full Text Available The neuroendocrine system is an important modulator of phenotype, directing cellular genetic responses to external cues such as temperature. Behavioural and physiological processes in poikilothermic organisms (e.g. most fishes, are particularly influenced by surrounding temperatures.By comparing the development and growth of two genotypes of coho salmon (wild-type and transgenic with greatly enhanced growth hormone production at six different temperatures, ranging between 8 degrees and 18 degrees C, we observed a genotype-temperature interaction and possible trend in directed neuroendocrine selection. Differences in growth patterns of the two genotypes were compared by using mathematical models, and morphometric analyses of juvenile salmon were performed to detect differences in body shape. The maximum hatching and alevin survival rates of both genotypes occurred at 12 degrees C. At lower temperatures, eggs containing embryos with enhanced GH production hatched after a shorter incubation period than wild-type eggs, but this difference was not apparent at and above 16 degrees C. GH transgenesis led to lower body weights at the time when the yolk sack was completely absorbed compared to the wild genotype. The growth of juvenile GH-enhanced salmon was to a greater extent stimulated by higher temperatures than the growth of the wild-type. Increased GH production significantly influenced the shape of the salmon growth curves.Growth hormone overexpression by transgenesis is able to stimulate the growth of coho salmon over a wide range of temperatures. Temperature was found to affect growth rate, survival, and body morphology between GH transgenic and wild genotype coho salmon, and differential responses to temperature observed between the genotypes suggests they would experience different selective forces should they ever enter natural ecosystems. Thus, GH transgenic fish would be expected to differentially respond and adapt to shifts in environmental

Parasite spread at the domestic animal - wildlife interface: anthropogenic habitat use, phylogeny and body mass drive risk of cat and dog flea (Ctenocephalides spp.) infestation in wild mammals.

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Clark, Nicholas J; Seddon, Jennifer M; Šlapeta, Jan; Wells, Konstans

2018-01-08

Spillover of parasites at the domestic animal - wildlife interface is a pervasive threat to animal health. Cat and dog fleas (Ctenocephalides felis and C. canis) are among the world's most invasive and economically important ectoparasites. Although both species are presumed to infest a diversity of host species across the globe, knowledge on their distributions in wildlife is poor. We built a global dataset of wild mammal host associations for cat and dog fleas, and used Bayesian hierarchical models to identify traits that predict wildlife infestation probability. We complemented this by calculating functional-phylogenetic host specificity to assess whether fleas are restricted to hosts with similar evolutionary histories, diet or habitat niches. Over 130 wildlife species have been found to harbour cat fleas, representing nearly 20% of all mammal species sampled for fleas. Phylogenetic models indicate cat fleas are capable of infesting a broad diversity of wild mammal species through ecological fitting. Those that use anthropogenic habitats are at highest risk. Dog fleas, by contrast, have been recorded in 31 mammal species that are primarily restricted to certain phylogenetic clades, including canids, felids and murids. Both flea species are commonly reported infesting mammals that are feral (free-roaming cats and dogs) or introduced (red foxes, black rats and brown rats), suggesting the breakdown of barriers between wildlife and invasive reservoir species will increase spillover at the domestic animal - wildlife interface. Our empirical evidence shows that cat fleas are incredibly host-generalist, likely exhibiting a host range that is among the broadest of all ectoparasites. Reducing wild species' contact rates with domestic animals across natural and anthropogenic habitats, together with mitigating impacts of invasive reservoir hosts, will be crucial for reducing invasive flea infestations in wild mammals.

The Plasmodium falciparum pseudoprotease SERA5 regulates the kinetics and efficiency of malaria parasite egress from host erythrocytes.

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Christine R Collins

2017-07-01

Full Text Available Egress of the malaria parasite Plasmodium falciparum from its host red blood cell is a rapid, highly regulated event that is essential for maintenance and completion of the parasite life cycle. Egress is protease-dependent and is temporally associated with extensive proteolytic modification of parasite proteins, including a family of papain-like proteins called SERA that are expressed in the parasite parasitophorous vacuole. Previous work has shown that the most abundant SERA, SERA5, plays an important but non-enzymatic role in asexual blood stages. SERA5 is extensively proteolytically processed by a parasite serine protease called SUB1 as well as an unidentified cysteine protease just prior to egress. However, neither the function of SERA5 nor the role of its processing is known. Here we show that conditional disruption of the SERA5 gene, or of both the SERA5 and related SERA4 genes simultaneously, results in a dramatic egress and replication defect characterised by premature host cell rupture and the failure of daughter merozoites to efficiently disseminate, instead being transiently retained within residual bounding membranes. SERA5 is not required for poration (permeabilization or vesiculation of the host cell membrane at egress, but the premature rupture phenotype requires the activity of a parasite or host cell cysteine protease. Complementation of SERA5 null parasites by ectopic expression of wild-type SERA5 reversed the egress defect, whereas expression of a SERA5 mutant refractory to processing failed to rescue the phenotype. Our findings implicate SERA5 as an important regulator of the kinetics and efficiency of egress and suggest that proteolytic modification is required for SERA5 function. In addition, our study reveals that efficient egress requires tight control of the timing of membrane rupture.

Genetic Characterization of Trypanosoma cruzi DTUs in Wild Triatoma infestans from Bolivia: Predominance of TcI

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Brenière, Simone Frédérique; Aliaga, Claudia; Waleckx, Etienne; Buitrago, Rosio; Salas, Renata; Barnabé, Christian; Tibayrenc, Michel; Noireau, François

2012-01-01

Background The current persistence of Triatoma infestans (one of the main vectors of Chagas disease) in some domestic areas could be related to re-colonization by wild populations which are increasingly reported. However, the infection rate and the genetic characterization of the Trypanosoma cruzi strains infecting these populations are very limited. Methodology/Principal Findings Of 333 wild Triatoma infestans specimens collected from north to south of a Chagas disease endemic area in Bolivia, we characterized 234 stocks of Trypanosoma cruzi using mini-exon multiplex PCR (MMPCR) and sequencing the glucose phosphate isomerase (Gpi) gene. Of the six genetic lineages (“discrete typing units”; DTU) (TcI-VI) presently recognized in T. cruzi, TcI (99.1%) was overdominant on TcIII (0.9%) in wild Andean T. infestans, which presented a 71.7% infection rate as evaluated by microscopy. In the lowlands (Bolivian Chaco), 17 “dark morph” T. infestans were analyzed. None of them were positive for parasites after microscopic examination, although one TcI stock and one TcII stock were identified using MMPCR and sequencing. Conclusions/Significance By exploring large-scale DTUs that infect the wild populations of T. infestans, this study opens the discussion on the origin of TcI and TcV DTUs that are predominant in domestic Bolivian cycles. PMID:22685616

Sex-Specific Diurnal Immobility Induced by Forced Swim Test in Wild Type and Clock Gene Deficient Mice

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Ningyue Li

2015-03-01

Full Text Available Objective: The link between alterations in circadian rhythms and depression are well established, but the underlying mechanisms are far less elucidated. We investigated the circadian characteristics of immobility behavior in wild type (WT mice and mice with mutations in core Clock genes. Methods: All mice were tested with forced swim test (FST at 4 h intervals. Results: These experiments revealed significant diurnal rhythms associated with immobility behavior in both male and female WT mice with sex-different circadian properties. In addition, male mice showed significantly less immobility during the night phase in comparison to female mice. Female Per1Brdm1 mice also showed significant rhythmicity. However, the timing of rhythmicity was very different from that observed in female wild type mice. Male Per1Brdm1 mice showed a pattern of rhythmicity similar to that of wild type mice. Furthermore, female Per1Brdm1 mice showed higher duration of immobility in comparison to male Per1Brdm1 mice in both daytime and early night phases. Neither Per2Brdm1 nor ClockΔ19 mice showed significant rhythmicity, but both female Per2Brdm1 and ClockΔ19 mice had lower levels of immobility, compared to males. Conclusions: This study highlights the differences in the circadian characteristics of immobility induced by FST in WT, ClockΔ19, Per1, and Per2 deficient mice.

Forward genetic screening identifies a small molecule that blocks Toxoplasma gondii growth by inhibiting both host- and parasite-encoded kinases.

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Kevin M Brown

2014-06-01

Full Text Available The simultaneous targeting of host and pathogen processes represents an untapped approach for the treatment of intracellular infections. Hypoxia-inducible factor-1 (HIF-1 is a host cell transcription factor that is activated by and required for the growth of the intracellular protozoan parasite Toxoplasma gondii at physiological oxygen levels. Parasite activation of HIF-1 is blocked by inhibiting the family of closely related Activin-Like Kinase (ALK host cell receptors ALK4, ALK5, and ALK7, which was determined in part by use of an ALK4,5,7 inhibitor named SB505124. Besides inhibiting HIF-1 activation, SB505124 also potently blocks parasite replication under normoxic conditions. To determine whether SB505124 inhibition of parasite growth was exclusively due to inhibition of ALK4,5,7 or because the drug inhibited a second kinase, SB505124-resistant parasites were isolated by chemical mutagenesis. Whole-genome sequencing of these mutants revealed mutations in the Toxoplasma MAP kinase, TgMAPK1. Allelic replacement of mutant TgMAPK1 alleles into wild-type parasites was sufficient to confer SB505124 resistance. SB505124 independently impacts TgMAPK1 and ALK4,5,7 signaling since drug resistant parasites could not activate HIF-1 in the presence of SB505124 or grow in HIF-1 deficient cells. In addition, TgMAPK1 kinase activity is inhibited by SB505124. Finally, mice treated with SB505124 had significantly lower tissue burdens following Toxoplasma infection. These data therefore identify SB505124 as a novel small molecule inhibitor that acts by inhibiting two distinct targets, host HIF-1 and TgMAPK1.

Multilocus sequence typing of commensal and enteropathogenic Escherichia coli from domestic and wild lagomorphs in Italy

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Giorgia Dotto

2015-12-01

Full Text Available The aim of the study was to determine the multilocus sequence types of Escherichia coli from diseased farm rabbits and apparently healthy wild lagomorphs, and the genetic relatedness among them. Fifty-five enteropathogenic E. coli from reared rabbits and 32 from wild rabbits and hares were characterised by multilocus sequence typing (MLST according to the Michigan State University EcMLST scheme. Isolates were differentiated into 37 sequence types (STs, which were grouped into 8 clonal complexes (CCs. The most common ST was ST140 (CC31, followed by ST238 and ST119 (CC17. MLST analysis revealed 22 novel STs. Phylogenetic analyses showed a heterogeneous distribution of STs into 3 clusters of genetically related strains. The genetic relationship among STs of different origin and the detection of new, as well as previously described STs as human pathogens, indicate a widespread distribution and adaptability of particular lineages to different hosts. These findings highlight the need for further research to improve the knowledge about E. coli populations colonising the gut of lagomorphs and their zoonotic potential.

Maintenance erlotinib in advanced nonsmall cell lung cancer: cost-effectiveness in EGFR wild-type across Europe

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Walleser S

2012-09-01

Full Text Available Silke Walleser,1 Joshua Ray,2 Helge Bischoff,3 Alain Vergnenègre,4 Hubertus Rosery,5 Christos Chouaid,6 David Heigener,7 Javier de Castro Carpeño,8 Marcello Tiseo,9 Stefan Walzer21Health Economic Consultancy, Renens, Switzerland; 2F Hoffmann-La Roche Pharmaceuticals AG, Basel, Switzerland; 3Thoracic Hospital of Heidelberg, Heidelberg, Germany; 4Limoges University Hospital, Limoges, France; 5Assessment-in-Medicine GmbH, Loerrach, Germany; 6Hospital Saint Antoine, Paris, France; 7Hospital Grosshansdorf, Grosshansdorf, Germany; 8University Hospital La Paz, Madrid, Spain; 9University Hospital of Parma, Parma, ItalyBackground: First-line maintenance erlotinib in patients with locally advanced or metastatic nonsmall cell lung cancer (NSCLC has demonstrated significant overall survival and progression-free survival benefits compared with best supportive care plus placebo, irrespective of epidermal growth factor receptor (EGFR status (SATURN trial. The cost-effectiveness of first-line maintenance erlotinib in the overall SATURN population has been assessed and published recently, but analyses according to EGFR mutation status have not been performed yet, which was the rationale for assessing the cost-effectiveness of first-line maintenance erlotinib specifically in EGFR wild-type metastatic NSCLC.Methods: The incremental cost per life-year gained of first-line maintenance erlotinib compared with best supportive care in patients with EGFR wild-type stable metastatic NSCLC was assessed for five European countries (the United Kingdom, Germany, France, Spain, and Italy with an area-under-the-curve model consisting of three health states (progression-free survival, progressive disease, death. Log-logistic survival functions were fitted to Phase III patient-level data (SATURN to model progression-free survival and overall survival. The first-line maintenance erlotinib therapy cost (modeled for time to treatment cessation, medication cost in later lines, and

Proteomics of Arabidopsis Seed Germination : a Comparative Study of Wild-Type and Gibberellin-Deficient Seeds

NARCIS (Netherlands)

Gallardo, K.; Job, C.; Groot, S.P.C.; Puype, M.; Vandekerckhove, J.; Job, D.

2002-01-01

We examined the role of gibberellins (GAs) in germination of Arabidopsis seeds by a proteomic approach. For that purpose, we used two systems. The first system consisted of seeds of the GA-deficient ga1 mutant, and the second corresponded to wild-type seeds incubated in paclobutrazol, a specific GA

Nutrition and metabolism of parasitized and non-parasitized ruminants. Some approaches for studying the mode of action of parasites

International Nuclear Information System (INIS)

Leng, R.A.

1981-01-01

The effects of helminth infections on ruminant digestive function and metabolism are discussed against the background of current information on the mechanisms controlling feed intake and utilization in normal animals. Although parasites reduce productivity by impairing appetite and utilization of nutrients, few studies have been conducted on the function of the digestive tract and the metabolism of parasitized animals. Those areas which warrant further investigation are described, and the techniques which could be usefully applied are outlined. It is concluded that more emphasis should be given to the diet available to parasitized animals, and that by using diets of different digestibility and protein content, valuable information could be obtained as to the relative importance of reduced appetite and reduced efficiency of feed utilization. Central to all studies is a proper delineation of the fate of proteins in the small intestine of parasitized animals, and characterization of the types of bacteria in the gut and their effects on endogenous protein losses. The application of 15 N is mentioned. The potential usefulness of 14 C (eg. to measure the flow of digesta, to the lower digestive tract; clearance of 14 C-propionate from blood; etc.) is described

Modelling biological control with wild-type and genetically modified baculoviruses in the Helicoverpa armigera-cotton system

NARCIS (Netherlands)

Sun, X.; Werf, van der W.; Bianchi, F.J.J.A.; Hu, Z.; Vlak, J.M.

2006-01-01

A comprehensive model was developed to simulate virus epizootics in a stage structured insect population and analyse scenarios for the biological control of cotton bollworm (CBW), Helicoverpa armigera, in cotton, using wild-type or genetically modified baculoviruses. In simulations on dosage and

Leishmania donovani argininosuccinate synthase is an active enzyme associated with parasite pathogenesis.

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Ines Lakhal-Naouar

Full Text Available BACKGROUND: Gene expression analysis in Leishmania donovani (Ld identified an orthologue of the urea cycle enzyme, argininosuccinate synthase (LdASS, that was more abundantly expressed in amastigotes than in promastigotes. In order to characterize in detail this newly identified protein in Leishmania, we determined its enzymatic activity, subcellular localization in the parasite and affect on virulence in vivo. METHODOLOGY/PRINCIPAL FINDINGS: Two parasite cell lines either over expressing wild type LdASS or a mutant form (G128S associated with severe cases of citrullinemia in humans were developed. In addition we also produced bacterially expressed recombinant forms of the same proteins. Our results demonstrated that LdASS has argininosuccinate synthase enzymatic activity that is abolished using an ASS specific inhibitor (MDLA: methyl-D-L-Aspartic acid. However, the mutant form of the protein is inactive. We demonstrate that though LdASS has a glycosomal targeting signal that binds the targeting apparatus in vitro, only a small proportion of the total cellular ASS is localized in a vesicle, as indicated by protection from protease digestion of the crude organelle fraction. The majority of LdASS was found to be in the cytosolic fraction that may include large cytosolic complexes as indicated by the punctate distribution in IFA. Surprisingly, comparison to known glycosomal proteins by IFA revealed that LdASS was located in a structure different from the known glycosomal vesicles. Significantly, parasites expressing a mutant form of LdASS associated with a loss of in vitro activity had reduced virulence in vivo in BALB/c mice as demonstrated by a significant reduction in the parasite load in spleen and liver. CONCLUSION/SIGNIFICANCE: Our study suggests that LdASS is an active enzyme, with unique localization and essential for parasite survival and growth in the mammalian host. Based on these observations LdASS could be further explored as a

CD7 in acute myeloid leukemia: correlation with loss of wild-type CEBPA, consequence of epigenetic regulation

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Drexler Hans G

2010-04-01

Full Text Available Abstract Background CD7 is a negative prognostic marker in myeloid malignancies. In acute myeloid leukemia (AML, an inverse correlation exists between expression of wild-type CEBPA and CD7. Aim of this study was to find out whether C/EBPα is a negative regulator of CD7 and which other regulatory mechanisms might be involved. Results As already described for primary AML cells, the majority of AML cell lines tested were either C/EBPα+/CD7- or C/EBPα-/CD7+. However, the existence of isolated CD7+ cell lines expressing wild-type C/EBPα challenges the notion that C/EBPα acts as a unique repressor of CD7. Furthermore, ectopic expression of CEBPA did not reduce CD7 in CD7+ cells and knock-down of C/EBPα failed to induce CD7 in CD7- cells. In contrast, the DNA demethylating agent Aza-2'deoxycytidine triggered CD7 expression in CD7- AML and in T-cell lines suggesting epigenetic regulation of CD7. Bisulfite sequencing data confirmed that CpGs in the CD7 exon1 region are methylated in CD7- cell lines, and unmethylated in CD7+ cell lines. Conclusion We confirmed an inverse correlation between the expression of wild-type CEBPA and of CD7 in AML cells. Our results contradict the hypothesis that C/EBPα acts as repressor for CD7, and instead show that epigenetic mechanisms are responsible for CD7 regulation, in AML cells as well as in T-cells, the typical CD7 expressing cell type.

Partially dissecting the steady-state electron fluxes in Photosystem I in wild-type and pgr5 and ndh mutants of Arabidopsis

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Jiancun eKou

2015-09-01

Full Text Available Cyclic electron flux (CEF around Photosystem I (PS I is difficult to quantify. We obtained the linear electron flux (LEFO2 through both photosystems and the total electron flux through PS I (ETR1 in Arabidopsis in CO2-enriched air. DeltaFlux = ETR1 – LEFO2 is an upper estimate of CEF, which consists of two components, an antimycin A-sensitive, PGR5 (proton gradient regulation 5 protein-dependent component and an insensitive component facilitated by a chloroplastic nicotinamide adenine dinucleotide dehydrogenase-like complex (NDH. Using wild type as well as pgr5 and ndh mutants, we observed that (1 40% of the absorbed light was partitioned to PS I; (2 at high irradiance a substantial antimycin A-sensitive CEF occurred in the wild type and the ndh mutant; (3 at low irradiance a sizable antimycin A-sensitive CEF occurred in the wild type but not in the ndh mutant, suggesting an enhancing effect of NDH in low light; and (4 in the pgr5 mutant, and the wild type and ndh mutant treated with antimycin A, a residual DeltaFlux existed at high irradiance, attributable to charge recombination and/or pseudo-cyclic electron flow. Therefore, in low-light-acclimated plants exposed to high light, DeltaFlux has contributions from various paths of electron flow through PS I.

Hepcidin regulation in wild-type and Hfe knockout mice in response to alcohol consumption: evidence for an alcohol-induced hypoxic response.

Science.gov (United States)

Heritage, Mandy L; Murphy, Therese L; Bridle, Kim R; Anderson, Gregory J; Crawford, Darrell H G; Fletcher, Linda M

2009-08-01

Expression of Hamp1, the gene encoding the iron regulatory peptide hepcidin, is inappropriately low in HFE-associated hereditary hemochromatosis and Hfe knockout mice (Hfe(-/-)). Since chronic alcohol consumption is also associated with disturbances in iron metabolism, we investigated the effects of alcohol consumption on hepcidin mRNA expression in Hfe(-/-) mice. Hfe(-/-) and C57BL/6 (wild-type) mice were pair-fed either an alcohol liquid diet or control diet for up to 8 weeks. The mRNA levels of hepcidin and ferroportin were measured at the mRNA level by RT-PCR and protein expression of hypoxia inducible factor-1 alpha (HIF-1alpha) was measured by western blot. Hamp1 mRNA expression was significantly decreased and duodenal ferroportin expression was increased in alcohol-fed wild-type mice at 8 weeks. Time course experiments showed that the decrease in hepcidin mRNA was not immediate, but was significant by 4 weeks. Consistent with the genetic defect, Hamp1 mRNA was decreased and duodenal ferroportin mRNA expression was increased in Hfe(-/-) mice fed on the control diet compared with wild-type animals and alcohol further exacerbated these effects. HIF-1alpha protein levels were elevated in alcohol-fed wild-type animals compared with controls. Alcohol may decrease Hamp1 gene expression independently of the HFE pathway possibly via alcohol-induced hypoxia.

Infectious diseases, parasites, and biological toxins in sea ducks: Chapter 4

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Hollmén, Tuula E.; Franson, J. Christian

2015-01-01

This chapter addresses disease agents in the broad sense, including viruses, bacteria, fungi, protozoan and helminth parasites, and biological toxins. Some of these agents are known to cause mortality in sea ducks, some are thought to be incidental findings, and the significance of others is yet poorly understood. Although the focus of the chapter is on free-living sea ducks, the study of disease in this taxonomic group has been relatively limited and examples from captive sea ducks and other wild waterfowl are used to illustrate the pathogenicity of certain diseases. Much of the early work in sea ducks consisted of anecdotal and descriptive reports of parasites, but it was soon recognized that diseases such as avian cholera, renal coccidiosis, and intestinal infections with acanthocephalans were causes of mortality in wild populations. More recently, adenoviruses, reoviruses, and the newly emergent Wellfleet Bay virus, for example, also have been linked to die-offs of sea ducks. Declining populations of animals are particularly vulnerable to the threats posed by disease and it is important that we improve our understanding of the significance of disease in sea ducks. To conclude, we offer our recommendations for future directions in this field.

Antibody Prevalence to Influenza Type A in Wild Boar of Northern Ukraine.

Science.gov (United States)

Kovalenko, Ganna; Molozhanova, Alona; Halka, Ihor; Nychyk, Serhiy

2017-12-01

A preliminary serological survey was carried out to assess the likelihood of influenza A (IA) infection in wild boar and begin to characterize the role of wild boar in the epidemiology of the IA virus (IAV). Sera collected from 120 wild boar that were hunted in 2014 were tested. To detect antibodies to IA, a blocking the enzyme-linked immunosorbent assay (ELISA) was used. Thirty boar were collected from each of four oblasts in the north central and northwestern regions of Ukraine. Antibodies against IAV were detected in 27 samples (22.5%; 95% confidence interval 16.0-30.8) and in at least some of the wild boar from all of the four oblasts. This preliminary survey of IA antibodies in wild boar populations of northern Ukraine indicates a substantial frequency of exposure to IAV throughout the region. Infection of wild boar populations could provide an alternative or additional route for spillover from wild populations to domestic animals and humans.

Mutant INS-gene induced diabetes of youth: proinsulin cysteine residues impose dominant-negative inhibition on wild-type proinsulin transport.

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Ming Liu

2010-10-01

Full Text Available Recently, a syndrome of Mutant INS-gene-induced Diabetes of Youth (MIDY, derived from one of 26 distinct mutations has been identified as a cause of insulin-deficient diabetes, resulting from expression of a misfolded mutant proinsulin protein in the endoplasmic reticulum (ER of insulin-producing pancreatic beta cells. Genetic deletion of one, two, or even three alleles encoding insulin in mice does not necessarily lead to diabetes. Yet MIDY patients are INS-gene heterozygotes; inheritance of even one MIDY allele, causes diabetes. Although a favored explanation for the onset of diabetes is that insurmountable ER stress and ER stress response from the mutant proinsulin causes a net loss of beta cells, in this report we present three surprising and interlinked discoveries. First, in the presence of MIDY mutants, an increased fraction of wild-type proinsulin becomes recruited into nonnative disulfide-linked protein complexes. Second, regardless of whether MIDY mutations result in the loss, or creation, of an extra unpaired cysteine within proinsulin, Cys residues in the mutant protein are nevertheless essential in causing intracellular entrapment of co-expressed wild-type proinsulin, blocking insulin production. Third, while each of the MIDY mutants induces ER stress and ER stress response; ER stress and ER stress response alone appear insufficient to account for blockade of wild-type proinsulin. While there is general agreement that ultimately, as diabetes progresses, a significant loss of beta cell mass occurs, the early events described herein precede cell death and loss of beta cell mass. We conclude that the molecular pathogenesis of MIDY is initiated by perturbation of the disulfide-coupled folding pathway of wild-type proinsulin.

Development of lymphatic filarial parasite Wuchereria bancrofti (Spirurida: Onchocercidae) in mosquito species (Diptera: Culicidae) fed artificially on microfilaremic blood.

Science.gov (United States)

Paily, K P; Hoti, S L; Balaraman, K

2006-11-01

The efficiency of laboratory colonies of mosquitoes such as Anopheles stephensi Liston, Aedes aegypti (L.) Liverpool strain, Ae. aegypti wild type, Aedes albopictus (Skuse), Culex tritaeniorhynchus Giles, Culex sitiens Wiedemann, and Armigeres subalbatus Coquillett in supporting the development of Wuchereria bancrofti (Cobbold) (Spirurida: Onchocercidae) microfilariae to infective larvae was investigated. The mosquitoes were fed on heparinized microfilaremic human blood by using a membrane-feeding unit with Parafilm as membrane. The rate of infection, parasite development, and parasite burden were compared with that in the known vector mosquito Culex quinquefasciatus Say. Cx. quinquefasciatus showed the highest percentage of infection, followed by Ae. aegypti Liverpool strain and An. stephensi. The rate of development of the parasite was more or less similar in all the three species, and infective larvae were found on day 13. When the larvae were harvested on day 17, Cx. quinquefasciatus yielded the highest numbers, followed by Ae. aegypti Liverpool strain and An. stephensi. The percentage of infection was low, and the development was slow in Cx. tritaeniorhynchus compared with the other susceptible species. The parasite developed to second-stage larvae only by day 22 and to infective larvae by day 28. When 2-wk-old Cx. tritaeniorhynchus were fed on microfilaremic blood, they could develop the parasite to infective larvae by day 13 postfeeding. All other species of mosquitoes tested were found to be refractory to parasite development. It is shown that Cx. quinquefasciatus is the most suitable mosquito host for the production of infective larvae. However, Ae. aegypti Liverpool strain, which is commonly used for Brugia malayi filarial parasite, also can be used for generation of W. bancrofti infective larvae to circumvent the problem of maintaining two mosquito species.

Purine salvage in the apicomplexan Sarcocystis neurona, and generation of hypoxanthine-xanthine-guanine phosphoribosyltransferase-deficient clones for positive-negative selection of transgenic parasites.

Science.gov (United States)

Dangoudoubiyam, Sriveny; Zhang, Zijing; Howe, Daniel K

2014-09-01

Sarcocystis neurona is an apicomplexan parasite that causes severe neurological disease in horses and marine mammals. The Apicomplexa are all obligate intracellular parasites that lack purine biosynthesis pathways and rely on the host cell for their purine requirements. Hypoxanthine-xanthine-guanine phosphoribosyltransferase (HXGPRT) and adenosine kinase (AK) are key enzymes that function in two complementary purine salvage pathways in apicomplexans. Bioinformatic searches of the S. neurona genome revealed genes encoding HXGPRT, AK and all of the major purine salvage enzymes except purine nucleoside phosphorylase. Wild-type S. neurona were able to grow in the presence of mycophenolic acid (MPA) but were inhibited by 6-thioxanthine (6-TX), suggesting that the pathways involving either HXGPRT or AK are functional in this parasite. Prior work with Toxoplasma gondii demonstrated the utility of HXGPRT as a positive-negative selection marker. To enable the use of HXGPRT in S. neurona, the SnHXGPRT gene sequence was determined and a gene-targeting plasmid was transfected into S. neurona. SnHXGPRT-deficient mutants were selected with 6-TX, and single-cell clones were obtained. These Sn∆HXG parasites were susceptible to MPA and could be complemented using the heterologous T. gondii HXGPRT gene. In summary, S. neurona possesses both purine salvage pathways described in apicomplexans, thus allowing the use of HXGPRT as a positive-negative drug selection marker in this parasite.

STUDY DATA OF KRAS- AND RAS-UNMUTATED (WILD TYPE OF COLORECTAL CANCER

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V. A. Gorbunova

2015-01-01

Full Text Available  Analysis of latest trials, comparing treatment schemes including chemotherapy with anti-EGFR monoclonal antibodies or bevacizumab is presented in this article. The data in these trials is inconsistent, but detailed analysis of FIRE-3 trial allows to distinguish a wild-type RAS patient group that benefits most from chemotherapy with cetuximab or panitumumab as 1st line metastatic colorectal cancer treatment. A final analysis of this patient group in CALGB/SWOG 80 405 trial is pending. The RAS analysis is pivotal for choice of 1st line chemotherapy.

Do Healthy Monarchs Migrate Farther? Tracking Natal Origins of Parasitized vs. Uninfected Monarch Butterflies Overwintering in Mexico.

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Altizer, Sonia; Hobson, Keith A; Davis, Andrew K; De Roode, Jacobus C; Wassenaar, Leonard I

2015-01-01

Long-distance migration can lower parasite prevalence if strenuous journeys remove infected animals from wild populations. We examined wild monarch butterflies (Danaus plexippus) to investigate the potential costs of the protozoan Ophryocystis elektroscirrha on migratory success. We collected monarchs from two wintering sites in central Mexico to compare infection status with hydrogen isotope (δ2H) measurements as an indicator of latitude of origin at the start of fall migration. On average, uninfected monarchs had lower δ2H values than parasitized butterflies, indicating that uninfected butterflies originated from more northerly latitudes and travelled farther distances to reach Mexico. Within the infected class, monarchs with higher quantitative spore loads originated from more southerly latitudes, indicating that heavily infected monarchs originating from farther north are less likely to reach Mexico. We ruled out the alternative explanation that lower latitudes give rise to more infected monarchs prior to the onset of migration using citizen science data to examine regional differences in parasite prevalence during the summer breeding season. We also found a positive association between monarch wing area and estimated distance flown. Collectively, these results emphasize that seasonal migrations can help lower infection levels in wild animal populations. Our findings, combined with recent declines in the numbers of migratory monarchs wintering in Mexico and observations of sedentary (winter breeding) monarch populations in the southern U.S., suggest that shifts from migratory to sedentary behavior will likely lead to greater infection prevalence for North American monarchs.

Do Healthy Monarchs Migrate Farther? Tracking Natal Origins of Parasitized vs. Uninfected Monarch Butterflies Overwintering in Mexico.

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Sonia Altizer

Full Text Available Long-distance migration can lower parasite prevalence if strenuous journeys remove infected animals from wild populations. We examined wild monarch butterflies (Danaus plexippus to investigate the potential costs of the protozoan Ophryocystis elektroscirrha on migratory success. We collected monarchs from two wintering sites in central Mexico to compare infection status with hydrogen isotope (δ2H measurements as an indicator of latitude of origin at the start of fall migration. On average, uninfected monarchs had lower δ2H values than parasitized butterflies, indicating that uninfected butterflies originated from more northerly latitudes and travelled farther distances to reach Mexico. Within the infected class, monarchs with higher quantitative spore loads originated from more southerly latitudes, indicating that heavily infected monarchs originating from farther north are less likely to reach Mexico. We ruled out the alternative explanation that lower latitudes give rise to more infected monarchs prior to the onset of migration using citizen science data to examine regional differences in parasite prevalence during the summer breeding season. We also found a positive association between monarch wing area and estimated distance flown. Collectively, these results emphasize that seasonal migrations can help lower infection levels in wild animal populations. Our findings, combined with recent declines in the numbers of migratory monarchs wintering in Mexico and observations of sedentary (winter breeding monarch populations in the southern U.S., suggest that shifts from migratory to sedentary behavior will likely lead to greater infection prevalence for North American monarchs.

The bacterial parasite Pasteuria ramosa is not killed if it fails to infect: implications for coevolution.

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King, Kayla C; Auld, Stuart K J R; Wilson, Philip J; James, Janna; Little, Tom J

2013-02-01

Strong selection on parasites, as well as on hosts, is crucial for fueling coevolutionary dynamics. Selection will be especially strong if parasites that encounter resistant hosts are destroyed and diluted from the local environment. We tested whether spores of the bacterial parasite Pasteuria ramosa were passed through the gut (the route of infection) of their host, Daphnia magna, and whether passaged spores remained viable for a "second chance" at infecting a new host. In particular, we tested if this viability (estimated via infectivity) depended on host genotype, whether or not the genotype was susceptible, and on initial parasite dose. Our results show that Pasteuria spores generally remain viable after passage through both susceptible and resistant Daphnia. Furthermore, these spores remained infectious even after being frozen for several weeks. If parasites can get a second chance at infecting hosts in the wild, selection for infection success in the first instance will be reduced. This could also weaken reciprocal selection on hosts and slow the coevolutionary process.

Parasites in the Wadden Sea food web

NARCIS (Netherlands)

Thieltges, D.W.; Engelsma, M.Y.; Wendling, C.C.; Wegner, K.M.

2013-01-01

While the free-living fauna of the Wadden Sea has received much interest, little is known on the distribution and effects of parasites in the Wadden Sea food web. However, recent studies on this special type of trophic interaction indicate a high diversity of parasites in the Wadden Sea and suggest

Bee declines driven by combined stress from parasites, pesticides, and lack of flowers.

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Goulson, Dave; Nicholls, Elizabeth; Botías, Cristina; Rotheray, Ellen L

2015-03-27

Bees are subject to numerous pressures in the modern world. The abundance and diversity of flowers has declined; bees are chronically exposed to cocktails of agrochemicals, and they are simultaneously exposed to novel parasites accidentally spread by humans. Climate change is likely to exacerbate these problems in the future. Stressors do not act in isolation; for example, pesticide exposure can impair both detoxification mechanisms and immune responses, rendering bees more susceptible to parasites. It seems certain that chronic exposure to multiple interacting stressors is driving honey bee colony losses and declines of wild pollinators, but such interactions are not addressed by current regulatory procedures, and studying these interactions experimentally poses a major challenge. In the meantime, taking steps to reduce stress on bees would seem prudent; incorporating flower-rich habitat into farmland, reducing pesticide use through adopting more sustainable farming methods, and enforcing effective quarantine measures on bee movements are all practical measures that should be adopted. Effective monitoring of wild pollinator populations is urgently needed to inform management strategies into the future. Copyright © 2015, American Association for the Advancement of Science.

A novel Meloidogyne graminicola effector, MgGPP, is secreted into host cells and undergoes glycosylation in concert with proteolysis to suppress plant defenses and promote parasitism.

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Jiansong Chen

2017-04-01

Full Text Available Plant pathogen effectors can recruit the host post-translational machinery to mediate their post-translational modification (PTM and regulate their activity to facilitate parasitism, but few studies have focused on this phenomenon in the field of plant-parasitic nematodes. In this study, we show that the plant-parasitic nematode Meloidogyne graminicola has evolved a novel effector, MgGPP, that is exclusively expressed within the nematode subventral esophageal gland cells and up-regulated in the early parasitic stage of M. graminicola. The effector MgGPP plays a role in nematode parasitism. Transgenic rice lines expressing MgGPP become significantly more susceptible to M. graminicola infection than wild-type control plants, and conversely, in planta, the silencing of MgGPP through RNAi technology substantially increases the resistance of rice to M. graminicola. Significantly, we show that MgGPP is secreted into host plants and targeted to the ER, where the N-glycosylation and C-terminal proteolysis of MgGPP occur. C-terminal proteolysis promotes MgGPP to leave the ER, after which it is transported to the nucleus. In addition, N-glycosylation of MgGPP is required for suppressing the host response. The research data provide an intriguing example of in planta glycosylation in concert with proteolysis of a pathogen effector, which depict a novel mechanism by which parasitic nematodes could subjugate plant immunity and promote parasitism and may present a promising target for developing new strategies against nematode infections.

lambda. -prophage induction in repair-deficient and wild type E. coli strains by. gamma. -rays and heavy ions

Energy Technology Data Exchange (ETDEWEB)

Bonev, M.N.; Kozubek, S.; Krasavin, E.A.; Amirtajev, K.G. (Joint Inst. for Nuclear Research, Dubna (USSR))

1990-05-01

{lambda}-prophage induction in repair-deficient and wild-type E. coli strains by heavy ions and {gamma}-rays was investigated. The dose dependence of the fraction of induced cells has been measured and its initial slope ({lambda}-induction potency) determined. Induction by {gamma}-rays was found to be more efficient in a polA-repair-deficient strain; the value of {lambda}-induction potency is zero in lexA{sup -} and recA{sup -} strains. The {lambda}-induction potency potency increased with LET for wild-type cells but remained constant in polA{sup -} mutant cells. It is suggested that DNA damage triggering the {lambda}-prophage induction in the case of ionizing radiation could be a type of DNA single-strand break with complex structures which cannot be repaired by fast repair processes, and requires a substantial level of energy deposition for induction in a DNA molecule. (author).

Mercury concentrations in wild mink (Mustela vison) and river otters (Lontra canadensis) collected from eastern and Atlantic Canada: Relationship to age and parasitism

Energy Technology Data Exchange (ETDEWEB)

Klenavic, Katherine [Environmental and Resource Studies, Trent University, 1600 West Bank Drive, Peterborough, ON K9J 7B8 (Canada); Champoux, Louise [Service Canadien de la Faune Environnement Canada, 1141 Route de l' Eglise, c.p. 10100, Sainte-Foy, QC G1V 4H5 (Canada)], E-mail: louise.champoux@ec.gc.ca; Mike, O' Brien [Furbearers and Upland Game, Department of Natural Resources, Kentville, NS B4N 4E5 (Canada)], E-mail: obrienms@gov.ns.ca; Daoust, Pierre-Y. [Department of Pathology and Microbiology, Atlantic Veterinary College, University of P.E.I., 550 University Avenue, Charlottetown, PEI C1A 4P3 (Canada)], E-mail: daoust@upei.ca; Evans, R. Douglas [Environmental and Resource Studies, Trent University, 1600 West Bank Drive, Peterborough, ON K9J 7B8 (Canada); Evans, Hayla E. [Environmental and Resource Studies, Trent University, 1600 West Bank Drive, Peterborough, ON K9J 7B8 (Canada)], E-mail: hevans@trentu.ca

2008-11-15

Total mercury (Hg) concentrations were measured in the fur, brain and liver of wild mink (Mustela vison) and river otters (Lontra canadensis) collected from eastern and Atlantic Canada. Total Hg concentrations in fur were strongly correlated with levels in the brain and liver. There was no difference in tissue concentrations between male and female mink; however, female otters had significantly higher fur, brain and liver Hg levels than males. Similarly, there was not a significant relationship between Hg concentration and age of mink, whereas in otters, Hg concentrations in all three tissues decreased significantly with age. In both species, only a very small percentage of the variability in Hg concentration was explained by age. After adjusting the data for site-to-site differences in Hg levels, Hg concentrations in the fur of mink infected by the parasite, Dioctophyma renale, were found to be significantly higher than Hg levels in uninfected mink. - Mercury (Hg) concentrations in liver, brain and fur are correlated in mink (Mustela vison) and otters (Lontra canadensis), allowing the use of fur as an indicator of internal tissue concentrations.

Mercury concentrations in wild mink (Mustela vison) and river otters (Lontra canadensis) collected from eastern and Atlantic Canada: Relationship to age and parasitism

International Nuclear Information System (INIS)

Klenavic, Katherine; Champoux, Louise; Mike, O'Brien; Daoust, Pierre-Y.; Evans, R. Douglas; Evans, Hayla E.

2008-01-01

Total mercury (Hg) concentrations were measured in the fur, brain and liver of wild mink (Mustela vison) and river otters (Lontra canadensis) collected from eastern and Atlantic Canada. Total Hg concentrations in fur were strongly correlated with levels in the brain and liver. There was no difference in tissue concentrations between male and female mink; however, female otters had significantly higher fur, brain and liver Hg levels than males. Similarly, there was not a significant relationship between Hg concentration and age of mink, whereas in otters, Hg concentrations in all three tissues decreased significantly with age. In both species, only a very small percentage of the variability in Hg concentration was explained by age. After adjusting the data for site-to-site differences in Hg levels, Hg concentrations in the fur of mink infected by the parasite, Dioctophyma renale, were found to be significantly higher than Hg levels in uninfected mink. - Mercury (Hg) concentrations in liver, brain and fur are correlated in mink (Mustela vison) and otters (Lontra canadensis), allowing the use of fur as an indicator of internal tissue concentrations

Gene expression during ovarian differentiation in parasitic and non-parasitic lampreys: implications for fecundity and life history types.

Science.gov (United States)

Spice, Erin K; Whyard, Steven; Docker, Margaret F

2014-11-01

Lampreys diverged from the jawed vertebrate lineage approximately 500million years ago. Lampreys undergo sex differentiation much later than most other vertebrates, and ovarian differentiation occurs several years before testicular differentiation. The genetic basis of lamprey sex differentiation is of particular interest both because of the phylogenetic importance of lampreys and because of their unusual pattern of sex differentiation. As well, differences between parasitic and non-parasitic lampreys may first become evident at ovarian differentiation. However, nothing is known about the genetic basis of ovarian differentiation in lampreys. This study examined potential differences in gene expression before, during, and after ovarian differentiation in parasitic chestnut lamprey Ichthyomyzon castaneus and non-parasitic northern brook lamprey Ichthyomyzonfossor. Eight target genes (17β-hydroxysteroid dehydrogenase, germ cell-less, estrogen receptor β, insulin-like growth factor 1 receptor, daz-associated protein 1, cytochrome c oxidase subunit III, Wilms' tumour suppressor protein 1, and dehydrocholesterol reductase 7) were examined. Northern brook lamprey displayed higher expression of cytochrome c oxidase subunit III, whereas chestnut lamprey displayed higher expression of insulin-like growth factor 1 receptor; these genes may be involved in apoptosis and oocyte growth, respectively. Presumptive male larvae had higher expression of Wilms' tumour suppressor protein 1, which may be involved in the undifferentiated gonad and/or later testicular development. Differentiated females had higher expression of 17β hydroxysteroid dehydrogenase and daz-associated protein 1, which may be involved in female development. This study is the first to identify genes that may be involved in ovarian differentiation and fecundity in lampreys. Copyright © 2014 Elsevier Inc. All rights reserved.

Parasitic arthropods of some wild rodents from Juréia-Itatins Ecological Station, State of São Paulo, Brazil

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Bossi David Eduardo Paolinetti

2002-01-01

Full Text Available A study of the associations between three species of rodents in the Atlantic forest and their parasitic arthropods was undertaken at the Juréia-Itatins Ecological Station, located in the State of São Paulo, Southeastern Brazil, from March 1989 to February 1990. Individuals of three species, Oryzomys russatus, Proechimys iheringi and Nectomys squamipes were captured and examined for ectoparasites. Eleven species of parasitic arthropods were found, including four species of insects and seven of Acari. Parasitism intensity, phenology, and rainfall were positively correlated with the abundance of the ectoparasites and their hosts. The most abundant host was O. russatus (Muridae: Sigmodontinae, and the most common parasite on it was the laelapid mite Gigantolaelaps oudemansi. The cuterebrid Metacuterebra apicalis caused myiasis in O. russatus. A mutualistic association between the staphylinid beetle Amblyopinus sp. and its host P. iheringi (Echimyidae was observed. The few N. squamipes captured had small numbers of ectoparasites.

Assessing the diversity, host-specificity and infection patterns of apicomplexan parasites in reptiles from Oman, Arabia.

Science.gov (United States)

Maia, João P; Harris, D James; Carranza, Salvador; Goméz-Díaz, Elena

2016-11-01

Understanding the processes that shape parasite diversification, their distribution and abundance provides valuable information on the dynamics and evolution of disease. In this study, we assessed the diversity, distribution, host-specificity and infection patterns of apicomplexan parasites in amphibians and reptiles from Oman, Arabia. Using a quantitative PCR approach we detected three apicomplexan parasites (haemogregarines, lankesterellids and sarcocystids). A total of 13 haemogregarine haplotypes were identified, which fell into four main clades in a phylogenetic framework. Phylogenetic analysis of six new lankesterellid haplotypes revealed that these parasites were distinct from, but phylogenetically related to, known Lankesterella species and might represent new taxa. The percentage of infected hosts (prevalence) and the number of haemogregarines in the blood (parasitaemia) varied significantly between gecko species. We also found significant differences in parasitaemia between haemogregarine parasite lineages (defined by phylogenetic clustering of haplotypes), suggesting differences in host-parasite compatibility between these lineages. For Pristurus rupestris, we found significant differences in haemogregarine prevalence between geographical areas. Our results suggest that host ecology and host relatedness may influence haemogregarine distributions and, more generally, highlight the importance of screening wild hosts from remote regions to provide new insights into parasite diversity.

A novel copro-diagnostic molecular method for qualitative detection and identification of parasitic nematodes in amphibians and reptiles.

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Lucas G Huggins

Full Text Available Anthropogenic disturbance via resource acquisition, habitat fragmentation and climate change, amongst other factors, has led to catastrophic global biodiversity losses and species extinctions at an accelerating rate. Amphibians are currently one of the worst affected classes with at least a third of species categorised as being threatened with extinction. At the same time, they are also critically important for many habitats and provide man with a powerful proxy for ecosystem health by acting as a bioindicator group. Whilst the causes of synchronised amphibian losses are varied recent research has begun to highlight a growing role that macroparasites are playing in amphibian declines. However, diagnosing parasite infection in the field can be problematic, principally relying on collection and euthanasia of hosts, followed by necropsy and morphological identification of parasites in situ. The current study developed a non-invasive PCR-based methodology for sensitive detection and identification of parasitic nematode DNA released in the faeces of infected amphibians as egg or tissue fragments (environmental DNA. A DNA extraction protocol optimised for liberation of DNA from resilient parasite eggs was developed alongside the design of a novel, nematode universal, degenerate primer pair, thus avoiding the difficulties of using species specific primers in situations where common parasite species are unknown. Used in conjunction this protocol and primer pair was tested on a wide range of faecal samples from captive and wild amphibians. The primers and protocol were validated and detected infections, including a Railletnema nematode infection in poison dart frogs from ZSL London Zoo and Mantella cowani frogs in the wild. Furthermore, we demonstrate the efficacy of our PCR-based protocol for detecting nematode infection in other hosts, such as the presence of pinworm (Aspiculuris in two tortoise species and whipworm (Trichuris muris in mice. Our

A novel copro-diagnostic molecular method for qualitative detection and identification of parasitic nematodes in amphibians and reptiles.

Science.gov (United States)

Huggins, Lucas G; Michaels, Christopher J; Cruickshank, Sheena M; Preziosi, Richard F; Else, Kathryn J

2017-01-01

Anthropogenic disturbance via resource acquisition, habitat fragmentation and climate change, amongst other factors, has led to catastrophic global biodiversity losses and species extinctions at an accelerating rate. Amphibians are currently one of the worst affected classes with at least a third of species categorised as being threatened with extinction. At the same time, they are also critically important for many habitats and provide man with a powerful proxy for ecosystem health by acting as a bioindicator group. Whilst the causes of synchronised amphibian losses are varied recent research has begun to highlight a growing role that macroparasites are playing in amphibian declines. However, diagnosing parasite infection in the field can be problematic, principally relying on collection and euthanasia of hosts, followed by necropsy and morphological identification of parasites in situ. The current study developed a non-invasive PCR-based methodology for sensitive detection and identification of parasitic nematode DNA released in the faeces of infected amphibians as egg or tissue fragments (environmental DNA). A DNA extraction protocol optimised for liberation of DNA from resilient parasite eggs was developed alongside the design of a novel, nematode universal, degenerate primer pair, thus avoiding the difficulties of using species specific primers in situations where common parasite species are unknown. Used in conjunction this protocol and primer pair was tested on a wide range of faecal samples from captive and wild amphibians. The primers and protocol were validated and detected infections, including a Railletnema nematode infection in poison dart frogs from ZSL London Zoo and Mantella cowani frogs in the wild. Furthermore, we demonstrate the efficacy of our PCR-based protocol for detecting nematode infection in other hosts, such as the presence of pinworm (Aspiculuris) in two tortoise species and whipworm (Trichuris muris) in mice. Our environmental DNA

Natural infection by endoparasites among free-living wild animals Infecção natural por endoparasitas em animais silvestres de vida-livre

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Luciane Holsback

Full Text Available The objective of this study was to investigate the frequency of occurrence and variety of intestinal parasites among free-living wild animals. Fecal samples from wild mammals and birds at rehabilitation centers in the states of Mato Grosso do Sul and São Paulo were analyzed by sedimentation and flotation-centrifugation methods. Parasite eggs, oocysts, cysts and/or trophozoites were found in 71% of the samples. Cryptosporidium sp. oocysts were detected in fecal samples from oncillas (Leopardus tigrinus and scaly-headed parrots (Pionus maximiliani. Giardia cysts were identified in the feces of a gray brocket (Mazama gouazoubira. Among the most common parasites found, there were eggs from Toxocara cati, Toxascaris leonina and Ancylostoma tubaeforme, and from Cestoda. Several Enterobius sp. eggs were found in the feces of red howler monkeys (Alouatta seniculus. It can be concluded from this study that despite the small number of samples, the diversity of parasites found was noteworthy. Additional information about parasite endofauna in wild animals is needed, since their presence might suggest that there could be proximity to and interactions with domestic animals and/or humans. In addition, further studies on parasites from free-living wild animals are of prime importance for understanding the intensity of anthropic changes in wild environments.O objetivo deste trabalho foi pesquisar a frequência de ocorrência e a variedade de parasitas intestinais de animais silvestres de vida livre. Amostras de fezes de mamíferos e aves silvestres de centros de reabilitação dos Estados do Mato Grosso do Sul e São Paulo, foram analisadas pelos métodos de sedimentação e de centrífugo-flutuação. Foram encontrados ovos, oocistos, cistos e/ou trofozoítos de parasitas em 71% das amostras. Oocistos de Cryptosporidium sp. foram detectados em amostras de fezes de gato-do-mato-pequeno (Leopardus tigrinus e maritacas (Pionus maximiliani. Cistos de Giardia

Tulbaghia violacea and Allium ursinum Extracts Exhibit Anti-Parasitic and Antimicrobial Activities.

Science.gov (United States)

Krstin, Sonja; Sobeh, Mansour; Braun, Markus Santhosh; Wink, Michael

2018-02-02

Garlic has played an important role in culinary arts and remedies in the traditional medicine throughout human history. Parasitic infections represent a burden in the society of especially poor countries, causing more than 1 billion infections every year and leading to around one million deaths. In this study, we investigated the mode of anti-parasitic activity of "wild garlics" Tulbaghia violacea and Allium ursinum dichloromethane extracts against parasites Trypanosoma brucei brucei and Leishmania tarentolae with regard to their already known antimicrobial activity. We also evaluated their cytotoxic potential against human cells. Both extracts showed a relevant trypanocidal and leishmanicidal activity, although L. tarentolae was less sensitive. We determined that the probable mode of action of both extracts is the irreversible inhibition of the activity of Trypanosoma brucei trypanothione reductase enzyme. The extracts showed a mild cytotoxic activity against human keratinocytes. They also exhibited weak-in most cases comparable-antibacterial and antifungal activity. HPLC-MS/MS analysis showed that both extracts are abundant in sulfur compounds. Thus, for the first time, the ability of Allium ursinum and Tulbaghia violacea to kill Trypanosoma sp. and Leishmania sp. parasites, probably by binding to and inactivating sulfur-containing compounds essential for the survival of the parasite, is shown.

Tulbaghia violacea and Allium ursinum Extracts Exhibit Anti-Parasitic and Antimicrobial Activities

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Sonja Krstin

2018-02-01

Full Text Available Garlic has played an important role in culinary arts and remedies in the traditional medicine throughout human history. Parasitic infections represent a burden in the society of especially poor countries, causing more than 1 billion infections every year and leading to around one million deaths. In this study, we investigated the mode of anti-parasitic activity of “wild garlics” Tulbaghia violacea and Allium ursinum dichloromethane extracts against parasites Trypanosoma brucei brucei and Leishmania tarentolae with regard to their already known antimicrobial activity. We also evaluated their cytotoxic potential against human cells. Both extracts showed a relevant trypanocidal and leishmanicidal activity, although L. tarentolae was less sensitive. We determined that the probable mode of action of both extracts is the irreversible inhibition of the activity of Trypanosoma brucei trypanothione reductase enzyme. The extracts showed a mild cytotoxic activity against human keratinocytes. They also exhibited weak—in most cases comparable—antibacterial and antifungal activity. HPLC-MS/MS analysis showed that both extracts are abundant in sulfur compounds. Thus, for the first time, the ability of Allium ursinum and Tulbaghia violacea to kill Trypanosoma sp. and Leishmania sp. parasites, probably by binding to and inactivating sulfur-containing compounds essential for the survival of the parasite, is shown.

Effects of animal type (wild vs. domestic) and diet alfalfa level on intake and digestibility of European adult rabbits (Oryctolagus cuniculus)

NARCIS (Netherlands)

Pinheiro, Victor; Outor-Monteiro, D.; Mourão, J.L.; Cone, J.W.; Guimaraes Dias Lourenco, Ana

2018-01-01

The aim of this study was to evaluate the effect of the level of alfalfa in the diet on feed intake and digestibility of two types of rabbits, wild (Oryctolagus cuniculus algirus) vs. domestic (O. cuniculus cuniculus). Ten wild (W; mean LW = 927 g) and 10 domestic (D; mean LW = 4,645 g) adult rabbit

The In Vivo Granulopoietic Response to Dexamethasone Injection Is Abolished in Perforin-Deficient Mutant Mice and Corrected by Lymphocyte Transfer from Nonsensitized Wild-Type Donors

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Pedro Xavier-Elsas

2015-01-01

Full Text Available Exogenously administered glucocorticoids enhance eosinophil and neutrophil granulocyte production from murine bone-marrow. A hematological response dependent on endogenous glucocorticoids underlies bone-marrow eosinophilia induced by trauma or allergic sensitization/challenge. We detected a defect in granulopoiesis in nonsensitized, perforin-deficient mice. In steady-state conditions, perforin- (Pfp- deficient mice showed significantly decreased bone-marrow and blood eosinophil and neutrophil counts, and colony formation in response to GM-CSF, relative to wild-type controls of comparable age and/or weight. By contrast, peripheral blood or spleen total cell and lymphocyte numbers were not affected by perforin deficiency. Dexamethasone enhanced colony formation by GM-CSF-stimulated progenitors from wild-type controls, but not Pfp mice. Dexamethasone injection increased bone-marrow eosinophil and neutrophil counts in wild-type controls, but not Pfp mice. Because perforin is expressed in effector lymphocytes, we examined whether this defect would be corrected by transferring wild-type lymphocytes into perforin-deficient recipients. Short-term reconstitution of the response to dexamethasone was separately achieved for eosinophils and neutrophils by transfer of distinct populations of splenic lymphocytes from nonsensitized wild-type donors. Transfer of the same amount of splenic lymphocytes from perforin-deficient donors was ineffective. This demonstrates that the perforin-dependent, granulopoietic response to dexamethasone can be restored by transfer of innate lymphocyte subpopulations.

Parasite epidemiology in a changing world: can molecular phylogeography help us tell the wood from the trees?

Science.gov (United States)

Morgan, E R; Clare, E L; Jefferies, R; Stevens, J R

2012-12-01

SUMMARY Molecular phylogeography has revolutionised our ability to infer past biogeographic events from cross-sectional data on current parasite populations. In ecological parasitology, this approach has been used to address fundamental questions concerning host-parasite co-evolution and geographic patterns of spread, and has raised many technical issues and problems of interpretation. For applied parasitologists, the added complexity inherent in adding population genetic structure to perceived parasite distributions can sometimes seem to cloud rather than clarify approaches to control. In this paper, we use case studies firstly to illustrate the potential extent of cryptic diversity in parasite and parasitoid populations, secondly to consider how anthropogenic influences including movement of domestic animals affect the geographic distribution and host associations of parasite genotypes, and thirdly to explore the applied relevance of these processes to parasites of socio-economic importance. The contribution of phylogeographic approaches to deeper understanding of parasite biology in these cases is assessed. Thus, molecular data on the emerging parasites Angiostrongylus vasorum in dogs and wild canids, and the myiasis-causing flies Lucilia spp. in sheep and Cochliomyia hominovorax in humans, lead to clear implications for control efforts to limit global spread. Broader applications of molecular phylogeography to understanding parasite distributions in an era of rapid global change are also discussed.

Role of UV-inducible proteins in repair of various wild-type Escherichia coli cells

International Nuclear Information System (INIS)

Sedliakova, M.; Slezarikova, V.; Brozmanova, J.; Masek, F.; Bayerova, V.

1980-01-01

3 wild-type strains of E. coli, namely K12 AB2497, B/r WP2 and 15 555-7, proficient in excision and post-replication repair, differ markedly in their UV resistance. To elucidate this difference, the influence was investigated of induction by application of inducing fluence (IF) before lethal fluence (LF) on repair processes after LF. In cells distinguished by low UV resistance (E. coli 15 555-7; E. coli B/r WP2), dimer excision was less complete in cultures irradiated with IF + LF than in cultures irradiated with LF only. The highly resistant E. coli K12 AB2497 performed complete excision both after IF + LF or after LF alone. All 3 types of cell survived better after IF + LF than after LF only. Because, in most strains so far investigated, the application of IF reduced dimer excision and increased survival, dimer excision per se does not appear important for survival. We conclude that the rate and completeness of dimer excision can serve as a measure of efficiency of the excision system whose action is necessary for repair of another lesion. Cells of all investigated strains could not resume DNA replication and died progressively when irradiated with LF and post-incubated with chloramphenicol (LF CAP + ). Thus, it appears that inducible proteins are necessary for repair in all wild-type E. coli cells given with potentially lethal doses of UV irradiation. (orig.)

Parasites in pet reptiles

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Mavri Urška

2011-05-01

Full Text Available Abstract Exotic reptiles originating from the wild can be carriers of many different pathogens and some of them can infect humans. Reptiles imported into Slovenia from 2000 to 2005, specimens of native species taken from the wild and captive bred species were investigated. A total of 949 reptiles (55 snakes, 331 lizards and 563 turtles, belonging to 68 different species, were examined for the presence of endoparasites and ectoparasites. Twelve different groups (Nematoda (5, Trematoda (1, Acanthocephala (1, Pentastomida (1 and Protozoa (4 of endoparasites were determined in 26 (47.3% of 55 examined snakes. In snakes two different species of ectoparasites were also found. Among the tested lizards eighteen different groups (Nematoda (8, Cestoda (1, Trematoda (1, Acanthocephala (1, Pentastomida (1 and Protozoa (6 of endoparasites in 252 (76.1% of 331 examined animals were found. One Trombiculid ectoparasite was determined. In 563 of examined turtles eight different groups (Nematoda (4, Cestoda (1, Trematoda (1 and Protozoa (2 of endoparasites were determined in 498 (88.5% animals. In examined turtles three different species of ectoparasites were seen. The established prevalence of various parasites in reptiles used as pet animals indicates the need for examination on specific pathogens prior to introduction to owners.

Efficient Reassignment of a Frequent Serine Codon in Wild-Type Escherichia coli.

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Ho, Joanne M; Reynolds, Noah M; Rivera, Keith; Connolly, Morgan; Guo, Li-Tao; Ling, Jiqiang; Pappin, Darryl J; Church, George M; Söll, Dieter

2016-02-19

Expansion of the genetic code through engineering the translation machinery has greatly increased the chemical repertoire of the proteome. This has been accomplished mainly by read-through of UAG or UGA stop codons by the noncanonical aminoacyl-tRNA of choice. While stop codon read-through involves competition with the translation release factors, sense codon reassignment entails competition with a large pool of endogenous tRNAs. We used an engineered pyrrolysyl-tRNA synthetase to incorporate 3-iodo-l-phenylalanine (3-I-Phe) at a number of different serine and leucine codons in wild-type Escherichia coli. Quantitative LC-MS/MS measurements of amino acid incorporation yields carried out in a selected reaction monitoring experiment revealed that the 3-I-Phe abundance at the Ser208AGU codon in superfolder GFP was 65 ± 17%. This method also allowed quantification of other amino acids (serine, 33 ± 17%; phenylalanine, 1 ± 1%; threonine, 1 ± 1%) that compete with 3-I-Phe at both the aminoacylation and decoding steps of translation for incorporation at the same codon position. Reassignments of different serine (AGU, AGC, UCG) and leucine (CUG) codons with the matching tRNA(Pyl) anticodon variants were met with varying success, and our findings provide a guideline for the choice of sense codons to be reassigned. Our results indicate that the 3-iodo-l-phenylalanyl-tRNA synthetase (IFRS)/tRNA(Pyl) pair can efficiently outcompete the cellular machinery to reassign select sense codons in wild-type E. coli.

Near-Infrared Spectroscopy, a Rapid Method for Predicting the Age of Male and Female Wild-Type and Wolbachia Infected Aedes aegypti.

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Maggy T Sikulu-Lord

2016-10-01

Full Text Available Estimating the age distribution of mosquito populations is crucial for assessing their capacity to transmit disease and for evaluating the efficacy of available vector control programs. This study reports on the capacity of the near-infrared spectroscopy (NIRS technique to rapidly predict the ages of the principal dengue and Zika vector, Aedes aegypti. The age of wild-type males and females, and males and females infected with wMel and wMelPop strains of Wolbachia pipientis were characterized using this method. Calibrations were developed using spectra collected from their heads and thoraces using partial least squares (PLS regression. A highly significant correlation was found between the true and predicted ages of mosquitoes. The coefficients of determination for wild-type females and males across all age groups were R2 = 0.84 and 0.78, respectively. The coefficients of determination for the age of wMel and wMelPop infected females were 0.71 and 0.80, respectively (P< 0.001 in both instances. The age of wild-type female Ae. aegypti could be identified as < or ≥ 8 days old with an accuracy of 91% (N = 501, whereas female Ae. aegypti infected with wMel and wMelPop were differentiated into the two age groups with an accuracy of 83% (N = 284 and 78% (N = 229, respectively. Our results also indicate NIRS can distinguish between young and old male wild-type, wMel and wMelPop infected Ae. aegypti with accuracies of 87% (N = 253, 83% (N = 277 and 78% (N = 234, respectively. We have demonstrated the potential of NIRS as a predictor of the age of female and male wild-type and Wolbachia infected Ae. aegypti mosquitoes under laboratory conditions. After field validation, the tool has the potential to offer a cheap and rapid alternative for surveillance of dengue and Zika vector control programs.

Imported Asian swamp eels (Synbranchidae: Monopterus) in North American live food markets: Potential vectors of non-native parasites

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Nico, Leo G.; Sharp, Paul; Collins, Timothy M.

2011-01-01

Since the 1990s, possibly earlier, large numbers of Asian swamp eels (Synbranchidae: Monopterus spp.), some wild-caught, have been imported live from various countries in Asia and sold in ethnic food markets in cities throughout the USA and parts of Canada. Such markets are the likely introduction pathway of some, perhaps most, of the five known wild populations of Asian swamp eels present in the continental United States. This paper presents results of a pilot study intended to gather baseline data on the occurrence and abundance of internal macroparasites infecting swamp eels imported from Asia to North American retail food markets. These data are important in assessing the potential role that imported swamp eels may play as possible vectors of non-native parasites. Examination of the gastrointestinal tracts and associated tissues of 19 adult-sized swamp eels—identified as M. albus "Clade C"—imported from Vietnam and present in a U.S. retail food market revealed that 18 (95%) contained macroparasites. The 394 individual parasites recovered included a mix of nematodes, acanthocephalans, cestodes, digeneans, and pentastomes. The findings raise concern because of the likelihood that some parasites infecting market swamp eels imported from Asia are themselves Asian taxa, some possibly new to North America. The ecological risk is exacerbated because swamp eels sold in food markets are occasionally retained live by customers and a few reportedly released into the wild. For comparative purposes, M. albus "Clade C" swamp eels from a non-native population in Florida (USA) were also examined and most (84%) were found to be infected with internal macroparasites. The current level of analysis does not allow us to confirm whether these are non-native parasites.

Zoonotic onchocerciasis caused by a parasite from wild boar in Oita, Japan

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Takaoka H.

2004-09-01

Full Text Available Histological examination of a nodule removed from the back of the hand of a 58-year-old woman from Oita, Kyushu, Japan showed an Onchocerca female sectioned through the posterior region of the worm (ovaries identifiable and young (thin cuticle. Six Onchocerca species are enzootic in that area: O. gutturosa and O. lienalis in cattle, O. suzukii in serows (Capricornis crispus, O. skrjabini and an Onchocerca sp. in Cervus nippon nippon, and O. dewittei japonica in wild boar (Sus scrofa leucomystax. Diagnostic charactets of female Onchocerca species, such as the cuticle and its ridges, change along the body length. Tables of the histologic morphology of the mid- and posterior body-regions of the local species are presented. In addition, it was observed that transverse ridges arose and thickened during the adult stage (examination of fourth stage and juvenile females of O. volvulus. The specimen described in this report, with its prominent and widely spaced ridges, was identified as O. d. japonica. Four of the 10 zoonotic cases of onchocerciasis reported worldwide were from Oita, three of them being caused by O. d. japonica, the prevalence of which in local wild boar was 22 of 24 (92 %.

Prevalence of Entamoeba nuttalli infection in wild rhesus macaques in Nepal and characterization of the parasite isolates.

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Tachibana, Hiroshi; Yanagi, Tetsuo; Lama, Chamala; Pandey, Kishor; Feng, Meng; Kobayashi, Seiki; Sherchand, Jeevan B

2013-04-01

We have recently resurrected the name Entamoeba nuttalli Castellani, 1908 for a potentially virulent ameba isolate, P19-061405, obtained from a rhesus macaque in Kathmandu, Nepal. The ameba was morphologically indistinguishable from Entamoeba histolytica/Entamoeba dispar/Entamoeba moshkovskii, but located phylogenetically between E. histolytica and E. dispar. To evaluate the prevalence of E. nuttalli infection in wild rhesus macaques, 112 fecal samples were collected in four locations of the Kathmandu Valley. PCR analysis of DNA extracted from the feces showed positive rates of E. nuttalli, E. dispar, E. histolytica and E. moshkovskii of 51%, 12%, 0% and 0%, respectively. A total of 14 E. nuttalli isolates were obtained from four locations, of which 6 were established as axenic cultures. The sequences of the serine-rich protein gene of E. nuttalli isolates differed among four locations although no differences were found in the composition of sequence motifs. Isoenzyme pattern was analyzed in 8 isolates obtained from three locations. In hexokinase, the mobility of the slower migrating band was located between E. histolytica and E. dispar regardless of the culture conditions. These results demonstrate that E. nuttalli is highly prevalent in wild rhesus macaques in Nepal. Rhesus macaques appear to be one of the natural hosts and heterogeneity of the serine-rich protein gene might be useful for geographical typing of isolates. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Gastrointestinal helminths of two populations of wild pigeons (Columba livia) in Brazil.

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Vaz, Frederico Fontanelli; Silva, Lidiane Aparecida Firmino da; Ferreira, Vivian Lindmayer; Silva, Reinaldo José da; Raso, Tânia Freitas

2017-01-01

The present study analyzed gastrointestinal helminth communities in 265 wild pigeons (Columba livia) living in the municipalities of São Paulo and Tatuí, state of São Paulo, Brazil, over a one-year period. The birds were caught next to grain storage warehouses and were necropsied. A total of 790 parasites comprising one nematode species and one cestode genus were recovered from 110 pigeons, thus yielding an overall prevalence of 41.5%, mean intensity of infection of 7.2 ± 1.6 (range 1-144) and discrepancy index of 0.855. Only 15 pigeons (5.7%) presented mixed infection. The helminths isolated from the birds were Ascaridia columbae (Ascaridiidae) and Raillietina sp. (Davaineidae). The birds' weights differed according to sex but this did not influence the intensity of infection. The overall prevalence and intensity of infection did not differ between the sexes, but the prevalence was higher among the birds from Tatuí (47.8%). The gastrointestinal helminth community of C. livia was characterized in the two areas studied and parasite homogeneity was observed over the 12 months analyzed at both locations. These results make contributions to the current literature on health aspects of wild C. livia populations.

Prevalence of Cryptosporidium spp., Enterocytozoon bieneusi, Encephalitozoon spp. and Giardia intestinalis in Wild, Semi-Wild and Captive Orangutans (Pongo abelii and Pongo pygmaeus) on Sumatra and Borneo, Indonesia.

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Mynářová, Anna; Foitová, Ivona; Kváč, Martin; Květoňová, Dana; Rost, Michael; Morrogh-Bernard, Helen; Nurcahyo, Wisnu; Nguyen, Cathleen; Supriyadi, Supriyadi; Sak, Bohumil

2016-01-01

Orangutans are critically endangered primarily due to loss and fragmentation of their natural habitat. This could bring them into closer contact with humans and increase the risk of zoonotic pathogen transmission. To describe the prevalence and diversity of Cryptosporidium spp., microsporidia and Giardia intestinalis in orangutans at seven sites on Sumatra and Kalimantan, and to evaluate the impact of orangutans' habituation and location on the occurrence of these zoonotic protists. The overall prevalence of parasites in 298 examined animals was 11.1%. The most prevalent microsporidia was Encephalitozoon cuniculi genotype II, found in 21 animals (7.0%). Enterocytozoon bieneusi genotype D (n = 5) and novel genotype Pongo 2 were detected only in six individuals (2.0%). To the best of our knowledge, this is the first report of these parasites in orangutans. Eight animals were positive for Cryptosporidium spp. (2.7%), including C. parvum (n = 2) and C. muris (n = 6). Giardia intestinalis assemblage B, subtype MB6, was identified in a single individual. While no significant differences between the different human contact level groups (p = 0.479-0.670) or between the different islands (p = 0.992) were reported in case of E. bieneusi or E. cuniculi, Cryptosporidium spp. was significantly less frequently detected in wild individuals (p < 2×10-16) and was significantly more prevalent in orangutans on Kalimantan than on Sumatra (p < 2×10-16). Our results revealed that wild orangutans are significantly less frequently infected by Cryptosporidium spp. than captive and semi-wild animals. In addition, this parasite was more frequently detected at localities on Kalimantan. In contrast, we did not detect any significant difference in the prevalence of microsporidia between the studied groups of animals. The sources and transmission modes of infections were not determined, as this would require repeated sampling of individuals, examination of water sources, and sampling of humans

Prevalence of Cryptosporidium spp., Enterocytozoon bieneusi, Encephalitozoon spp. and Giardia intestinalis in Wild, Semi-Wild and Captive Orangutans (Pongo abelii and Pongo pygmaeus on Sumatra and Borneo, Indonesia.

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Anna Mynářová

Full Text Available Orangutans are critically endangered primarily due to loss and fragmentation of their natural habitat. This could bring them into closer contact with humans and increase the risk of zoonotic pathogen transmission.To describe the prevalence and diversity of Cryptosporidium spp., microsporidia and Giardia intestinalis in orangutans at seven sites on Sumatra and Kalimantan, and to evaluate the impact of orangutans' habituation and location on the occurrence of these zoonotic protists.The overall prevalence of parasites in 298 examined animals was 11.1%. The most prevalent microsporidia was Encephalitozoon cuniculi genotype II, found in 21 animals (7.0%. Enterocytozoon bieneusi genotype D (n = 5 and novel genotype Pongo 2 were detected only in six individuals (2.0%. To the best of our knowledge, this is the first report of these parasites in orangutans. Eight animals were positive for Cryptosporidium spp. (2.7%, including C. parvum (n = 2 and C. muris (n = 6. Giardia intestinalis assemblage B, subtype MB6, was identified in a single individual. While no significant differences between the different human contact level groups (p = 0.479-0.670 or between the different islands (p = 0.992 were reported in case of E. bieneusi or E. cuniculi, Cryptosporidium spp. was significantly less frequently detected in wild individuals (p < 2×10-16 and was significantly more prevalent in orangutans on Kalimantan than on Sumatra (p < 2×10-16.Our results revealed that wild orangutans are significantly less frequently infected by Cryptosporidium spp. than captive and semi-wild animals. In addition, this parasite was more frequently detected at localities on Kalimantan. In contrast, we did not detect any significant difference in the prevalence of microsporidia between the studied groups of animals. The sources and transmission modes of infections were not determined, as this would require repeated sampling of individuals, examination of water sources, and sampling of

Recovery of deficient homologous recombination in Brca2-depleted mouse cells by wild-type Rad51 expression.

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Lee, Shauna A; Roques, Céline; Magwood, Alissa C; Masson, Jean-Yves; Baker, Mark D

2009-02-01

The BRCA2 tumor suppressor is important in maintaining genomic stability. BRCA2 is proposed to control the availability, cellular localization and DNA binding activity of the central homologous recombination protein, RAD51, with loss of BRCA2 resulting in defective homologous recombination. Nevertheless, the roles of BRCA2 in regulating RAD51 and how other proteins implicated in RAD51 regulation, such as RAD52 and RAD54 function relative to BRCA2 is not known. In this study, we tested whether defective homologous recombination in Brca2-depleted mouse hybridoma cells could be rectified by expression of mouse Rad51 or the Rad51-interacting mouse proteins, Rad52 and Rad54. In the Brca2-depleted cells, defective homologous recombination can be restored by over-expression of wild-type mouse Rad51, but not mouse Rad52 or Rad54. Correction of the homologous recombination defect requires Rad51 ATPase activity. A sizeable fraction ( approximately 50%) of over-expressed wild-type Rad51 is nuclear localized. The restoration of homologous recombination in the presence of a low (i.e., non-functional) level of Brca2 by wild-type Rad51 over-expression is unexpected. We suggest that Rad51 may access the nuclear compartment in a Brca2-independent manner and when Rad51 is over-expressed, the normal requirement for Brca2 control over Rad51 function in homologous recombination is dispensable. Our studies support loss of Rad51 function as a critical underlying factor in the homologous recombination defect in the Brca2-depleted cells.

Parasite stress promotes homicide and child maltreatment

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Thornhill, Randy; Fincher, Corey L.

2011-01-01

Researchers using the parasite-stress theory of human values have discovered many cross-cultural behavioural patterns that inform a range of scholarly disciplines. Here, we apply the theory to major categories of interpersonal violence, and the empirical findings are supportive. We hypothesize that the collectivism evoked by high parasite stress is a cause of adult-on-adult interpersonal violence. Across the US states, parasite stress and collectivism each positively predicts rates of men's and women's slaying of a romantic partner, as well as the rate of male-honour homicide and of the motivationally similar felony-related homicide. Of these four types of homicide, wealth inequality has an independent effect only on rates of male-honour and felony-related homicide. Parasite stress and collectivism also positively predict cross-national homicide rates. Child maltreatment by caretakers is caused, in part, by divestment in offspring of low phenotypic quality, and high parasite stress produces more such offspring than low parasite stress. Rates of each of two categories of the child maltreatment—lethal and non-lethal—across the US states are predicted positively by parasite stress, with wealth inequality and collectivism having limited effects. Parasite stress may be the strongest predictor of interpersonal violence to date. PMID:22042922

Gastrointestinal parasites of the chimpanzee population introduced onto Rubondo Island National Park, Tanzania.

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Petrzelková, Klára J; Hasegawa, Hideo; Appleton, Chris C; Huffman, Michael A; Archer, Colleen E; Moscovice, Liza R; Mapua, Mwanahamissi Issa; Singh, Jatinder; Kaur, Taranjit

2010-04-01

The release of any species into a novel environment can evoke transmission of parasites that do not normally parasitize the host as well as potentially introducing new parasites into the environment. Species introductions potentially incur such risks, yet little is currently known about the parasite fauna of introduced primate species over the long term. We describe the results of long-term monitoring of the intestinal parasite fauna of an unprovisioned, reproducing population of chimpanzees introduced 40 years earlier (1966-1969) onto Rubondo Island in Lake Victoria, Tanzania, a non-native habitat for chimpanzees. Two parasitological surveys (March 1997-October 1998 and October 2002-December 2005) identified Entamoeba spp. including E. coli, Iodamoeba buetschlii, Troglodytella abrassarti, Chilomastix mesnili, Trichuris sp., Anatrichosoma sp., Strongyloides spp., Strongylida fam. gen. sp., Enterobius anthropopitheci, Subulura sp., Ascarididae gen. sp., and Protospirura muricola. The parasite fauna of the Rubondo chimpanzees is similar to wild chimpanzees living in their natural habitats, but Rubondo chimpanzees have a lower prevalence of strongylids (9%, 3.8%) and a higher prevalence of E. anthropopitheci (8.6%, 17.9%) than reported elsewhere. Species prevalence was similar between our two surveys, with the exception of Strongyloides spp. being higher in the first survey. None of these species are considered to pose a serious health risk to chimpanzees, but continued monitoring of the population and surveys of the parasitic fauna of the two coinhabitant primate species and other animals, natural reservoir hosts of some of the same parasites, is important to better understand the dynamics of host-parasite ecology and potential long-term implications for chimpanzees introduced into a new habitat. 2009 Wiley-Liss, Inc.

Obligate brood parasites show more functionally effective innate immune responses: an eco-immunological hypothesis

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Hahn, D. Caldwell; Summers, Scott G.; Genovese, Kenneth J.; He, Haiqi; Kogut, Michael H.

2013-01-01

Immune adaptations of obligate brood parasites attracted interest when three New World cowbird species (Passeriformes, Icteridae, genus Molothrus) proved unusually resistant to West Nile virus. We have used cowbirds as models to investigate the eco-immunological hypothesis that species in parasite-rich environments characteristically have enhanced immunity as a life history adaptation. As part of an ongoing program to understand the cowbird immune system, in this study we measured degranulation and oxidative burst, two fundamental responses of the innate immune system. Innate immunity provides non-specific, fast-acting defenses against a variety of invading pathogens, and we hypothesized that innate immunity experiences particularly strong selection in cowbirds, because their life history strategy exposes them to diverse novel and unpredictable parasites. We compared the relative effectiveness of degranulation and oxidative burst responses in two cowbird species and one related, non-parasitic species. Both innate immune defenses were significantly more functionally efficient in the two parasitic cowbird species than in the non-parasitic red-winged blackbird (Icteridae, Agelaius phoeniceus). Additionally, both immune defenses were more functionally efficient in the brown-headed cowbird (M. ater), an extreme host-generalist brood parasite, than in the bronzed cowbird (M. aeneus), a moderate host-specialist with lower exposure to other species and their parasites. Thus the relative effectiveness of these two innate immune responses corresponds to the diversity of parasites in the niche of each species and to their relative resistance to WNV. This study is the first use of these two specialized assays in a comparative immunology study of wild avian species.

Helminth parasites alter protection against Plasmodium infection.

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Salazar-Castañon, Víctor H; Legorreta-Herrera, Martha; Rodriguez-Sosa, Miriam

2014-01-01

More than one-third of the world's population is infected with one or more helminthic parasites. Helminth infections are prevalent throughout tropical and subtropical regions where malaria pathogens are transmitted. Malaria is the most widespread and deadliest parasitic disease. The severity of the disease is strongly related to parasite density and the host's immune responses. Furthermore, coinfections between both parasites occur frequently. However, little is known regarding how concomitant infection with helminths and Plasmodium affects the host's immune response. Helminthic infections are frequently massive, chronic, and strong inductors of a Th2-type response. This implies that infection by such parasites could alter the host's susceptibility to subsequent infections by Plasmodium. There are a number of reports on the interactions between helminths and Plasmodium; in some, the burden of Plasmodium parasites increased, but others reported a reduction in the parasite. This review focuses on explaining many of these discrepancies regarding helminth-Plasmodium coinfections in terms of the effects that helminths have on the immune system. In particular, it focuses on helminth-induced immunosuppression and the effects of cytokines controlling polarization toward the Th1 or Th2 arms of the immune response.

Effects of social stress and intrauterine position on sexual phenotype in wild-type house mice (Mus musculus)

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William J. Zielinski; John G. Vandenbergh; Monica M. Montano

1991-01-01

Wild-type house mice were used to test the effect of intrauterine position on anogenital distance (AGD) and to verify whether crowding stress would masculinize female pups, developing at all intrauterine positions, as has been demonstrated in CF-1 mice stressed by restraint, heat, and...

Interferon-Mediated Innate Immune Responses against Malaria Parasite Liver Stages

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Jessica L. Miller

2014-04-01

Full Text Available Mosquito-transmitted malaria parasites infect hepatocytes and asymptomatically replicate as liver stages. Using RNA sequencing, we show that a rodent malaria liver-stage infection stimulates a robust innate immune response including type I interferon (IFN and IFNγ pathways. Liver-stage infection is suppressed by these infection-engendered innate responses. This suppression was abrogated in mice deficient in IFNγ, the type I IFN α/β receptor (IFNAR, and interferon regulatory factor 3. Natural killer and CD49b+CD3+ natural killer T (NKT cells increased in the liver after a primary infection, and CD1d-restricted NKT cells, which secrete IFNγ, were critical in reducing liver-stage burden of a secondary infection. Lack of IFNAR signaling abrogated the increase in NKT cell numbers in the liver, showing a link between type I IFN signaling, cell recruitment, and subsequent parasite elimination. Our findings demonstrate innate immune sensing of malaria parasite liver-stage infection and that the ensuing innate responses can eliminate the parasite.

PARASITIC CONTAMINATION OF WELLS DRINKING WATER IN MAZANDARAN PROVINCE

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Z. Yousefi ، H. Ziaei hezarjaribi ، A. A. Enayati ، R. A. Mohammadpoor

2009-10-01

Full Text Available There is a direct relation between the prevalence of some parasitic diseases and the presence of those etiologic agents in water. The purpose of this research was to determine the contamination rate of wells drinking water to parasites in Mazandaran province in the north of Iran. 989 water samples were randomly taken based on the population of towns and number of health centers from 12 cities of Mazandaran province and transferred to the laboratory in sterile containers. Water samples were then filtered and analyzed according to the World Health Organization guidelines. Direct method and Gram staining procedure were used to identify the parasites. If cryptosporidium was seen, floatation (sheather’s sugar and modified Ziehl-Neelsen staining method were performed. Parasites count was undertaken using McMaster counting slide (0.3 mL. 197 out of 989 water samples were contaminated with different parasites. From 197 contaminated samples, 20 different types of parasites were separated of which 53 (26.9% were pathogenic, 100 (50.8% non pathogenic, and 44 non-infective stages of parasites. Distance between wells and sources of contamination, type of water distribution systems, city and chlorination status had significantly statistical relationship with contamination prevalence (p<0.001. According to the results and considering the direct correlation between safe water and human health, proper implementation of providing hygienic drinking water should be enforced.

Dynamic analysis of a parasite population model

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Sibona, G. J.; Condat, C. A.

2002-03-01

We study the dynamics of a model that describes the competitive interaction between an invading species (a parasite) and its antibodies in an living being. This model was recently used to examine the dynamical competition between Tripanosoma cruzi and its antibodies during the acute phase of Chagas' disease. Depending on the antibody properties, the model yields three types of outcomes, corresponding, respectively, to healing, chronic disease, and host death. Here, we study the dynamics of the parasite-antibody interaction with the help of simulations, obtaining phase trajectories and phase diagrams for the system. We show that, under certain conditions, the size of the parasite inoculation can be crucial for the infection outcome and that a retardation in the stimulated production of an antibody species may result in the parasite gaining a definitive advantage. We also find a criterion for the relative sizes of the parameters that are required if parasite-generated decoys are indeed to help the invasion. Decoys may also induce a qualitatively different outcome: a limit cycle for the antibody-parasite population phase trajectories.

Characterization of a sensitive mouse Aβ40 PD biomarker assay for Alzheimer's disease drug development in wild-type mice.

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Lu, Yanmei; Hoyte, Kwame; Montgomery, William H; Luk, Wilman; He, Dongping; Meilandt, William J; Zuchero, Y Joy Yu; Atwal, Jasvinder K; Scearce-Levie, Kimberly; Watts, Ryan J; DeForge, Laura E

2016-05-01

Transgenic mice that overexpress human amyloid precursor protein with Swedish or London (APPswe or APPlon) mutations have been widely used for preclinical Alzheimer's disease (AD) drug development. AD patients, however, rarely possess these mutations or overexpress APP. We developed a sensitive ELISA that specifically and accurately measures low levels of endogenous Aβ40 in mouse plasma, brain and CSF. In wild-type mice treated with a bispecific anti-TfR/BACE1 antibody, significant Aβ reductions were observed in the periphery and the brain. APPlon transgenic mice showed a slightly less reduction, whereas APPswe mice did not have any decrease. This sensitive and well-characterized mouse Aβ40 assay enables the use of wild-type mice for preclinical PK/PD and efficacy studies of potential AD therapeutics.

Paternity-parasitism trade-offs: a model and test of host-parasite cooperation in an avian conspecific brood parasite.

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Lyon, Bruce E; Hochachka, Wesley M; Eadie, John M

2002-06-01

Efforts to evaluate the evolutionary and ecological dynamics of conspecific brood parasitism in birds and other animals have focused on the fitness costs of parasitism to hosts and fitness benefits to parasites. However, it has been speculated recently that, in species with biparental care, host males might cooperate with parasitic females by allowing access to the host nest in exchange for copulations. We develop a cost-benefit model to explore the conditions under which such host-parasite cooperation might occur. When the brood parasite does not have a nest of her own, the only benefit to the host male is siring some of the parasitic eggs (quasi-parasitism). Cooperation with the parasite is favored when the ratio of host male paternity of his own eggs relative to his paternity of parasitic eggs exceeds the cost of parasitism. When the brood parasite has a nest of her own, a host male can gain additional, potentially more important benefits by siring the high-value, low-cost eggs laid by the parasite in her own nest. Under these conditions, host males should be even more likely to accept parasitic eggs in return for copulations with the parasitic female. We tested these predictions for American coots (Fulica americana), a species with a high frequency of conspecific brood parasitism. Multilocus DNA profiling indicated that host males did not sire any of the parasitic eggs laid in host nests, nor did they sire eggs laid by the parasite in her own nest. We used field estimates of the model parameters from a four-year study of coots to predict the minimum levels of paternity required for the costs of parasitism to be offset by the benefits of mating with brood parasites. Observed levels of paternity were significantly lower than those predicted under a variety of assumptions, and we reject the hypothesis that host males cooperated with parasitic females. Our model clarifies the specific costs and benefits that influence host-parasite cooperation and, more generally

A lack of crowding? Body size does not decrease with density for two behavior-manipulating parasites

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Weinersmith, KL; Warinner, Chloe B.; Tan, Virgina; Harris, David J.; Mora, Adrienne B.; Kuris, Armand M.; Lafferty, Kevin D.; Hechinger, Ryan F.

2014-01-01

For trophically transmitted parasites that manipulate the phenotype of their hosts, whether the parasites do or do not experience resource competition depends on such factors as the size of the parasites relative to their hosts, the intensity of infection, the extent to which parasites share the cost of defending against the host’s immune system or manipulating their host, and the extent to which parasites share transmission goals. Despite theoretical expectations for situations in which either no, or positive, or negative density-dependence should be observed, most studies document only negative density-dependence for trophically transmitted parasites. However, this trend may be an artifact of most studies having focused on systems in which parasites are large relative to their hosts. Yet, systems are common where parasites are small relative to their hosts, and these trophically transmitted parasites may be less likely to experience resource limitation. We looked for signs of density-dependence in Euhaplorchis californiensis (EUHA) and Renicola buchanani (RENB), two manipulative trematode parasites infecting wild-caught California killifish (Fundulus parvipinnis). These parasites are small relative to killifish (suggesting resources are not limiting), and are associated with changes in killifish behavior that are dependent on parasite-intensity and that increase predation rates by the parasites’ shared final host (indicating the possibility for cost sharing). We did not observe negative density-dependence in either species, indicating that resources are not limiting. In fact, observed patterns indicate possible mild positive density-dependence for EUHA. Although experimental confirmation is required, our findings suggest that some behavior-manipulating parasites suffer no reduction in size, and may even benefit when "crowded" by conspecifics.

Pervasiveness of parasites in pollinators.

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Sophie E F Evison

Full Text Available Many pollinator populations are declining, with large economic and ecological implications. Parasites are known to be an important factor in the some of the population declines of honey bees and bumblebees, but little is known about the parasites afflicting most other pollinators, or the extent of interspecific transmission or vectoring of parasites. Here we carry out a preliminary screening of pollinators (honey bees, five species of bumblebee, three species of wasp, four species of hoverfly and three genera of other bees in the UK for parasites. We used molecular methods to screen for six honey bee viruses, Ascosphaera fungi, Microsporidia, and Wolbachia intracellular bacteria. We aimed simply to detect the presence of the parasites, encompassing vectoring as well as actual infections. Many pollinators of all types were positive for Ascosphaera fungi, while Microsporidia were rarer, being most frequently found in bumblebees. We also detected that most pollinators were positive for Wolbachia, most probably indicating infection with this intracellular symbiont, and raising the possibility that it may be an important factor in influencing host sex ratios or fitness in a diversity of pollinators. Importantly, we found that about a third of bumblebees (Bombus pascuorum and Bombus terrestris and a third of wasps (Vespula vulgaris, as well as all honey bees, were positive for deformed wing virus, but that this virus was not present in other pollinators. Deformed wing virus therefore does not appear to be a general parasite of pollinators, but does interact significantly with at least three species of bumblebee and wasp. Further work is needed to establish the identity of some of the parasites, their spatiotemporal variation, and whether they are infecting the various pollinator species or being vectored. However, these results provide a first insight into the diversity, and potential exchange, of parasites in pollinator communities.

Morphological effects on helminth parasites caused by herbicide under experimental conditions

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Tainá Carneiro de Castro Monte

2018-02-01

Full Text Available Abstract Helminth parasites have been studied as potential accumulators for different pollutants. Echinostoma paraensei is a foodborne trematode whose vertebrate host, the rodent Nectomys squamipes, is naturally exposed to environmental pesticides. However, little information exists regarding the pesticide’s effects on helminths. This study investigated the morphological effects on the trematode, E. paraensei, after experimental Roundup® herbicide exposure, in concentrations below those recommended for agricultural use. After two hours of exposure, scanning electron microscopy (SEM showed changes to the tegument, such as furrowing, shrinkage, peeling, spines loss on the peristomic collar, and histopathological evidence of altered cells in the cecum and acinus vitelline glands with vacuoles and structural changes to the muscular layers. Glycidic content was decreased, primarily in the connective tissue. As E. paraensei is an intestinal parasite of the semi-aquatic wild rodent, N. squamipes, it is predisposed to pesticide exposure resulting from agricultural practices. Therefore, we emphasize the need to evaluate its impact on helminth parasites, due to their pivotal role in regulating host populations.

Social Parasites

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Lopez, Miguel A.; Nguyen, HoangKim T.; Oberholzer, Michael; Hill, Kent L.

2011-01-01

Summary of recent advances Protozoan parasites cause tremendous human suffering worldwide, but strategies for therapeutic intervention are limited. Recent studies illustrate that the paradigm of microbes as social organisms can be brought to bear on questions about parasite biology, transmission and pathogenesis. This review discusses recent work demonstrating adaptation of social behaviors by parasitic protozoa that cause African sleeping sickness and malaria. The recognition of social behavior and cell-cell communication as a ubiquitous property of bacteria has transformed our view of microbiology, but protozoan parasites have not generally been considered in this context. Works discussed illustrate the potential for concepts of sociomicrobiology to provide insight into parasite biology and should stimulate new approaches for thinking about parasites and parasite-host interactions. PMID:22020108

Proxy measures of fitness suggest coastal fish farms can act as population sources and not ecological traps for wild gadoid fish.

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Tim Dempster

Full Text Available BACKGROUND: Ecological traps form when artificial structures are added to natural habitats and induce mismatches between habitat preferences and fitness consequences. Their existence in terrestrial systems has been documented, yet little evidence suggests they occur in marine environments. Coastal fish farms are widespread artificial structures in coastal ecosystems and are highly attractive to wild fish. METHODOLOGY/PRINCIPAL FINDINGS: To investigate if coastal salmon farms act as ecological traps for wild Atlantic cod (Gadus morhua and saithe (Pollachius virens, we compared proxy measures of fitness between farm-associated fish and control fish caught distant from farms in nine locations throughout coastal Norway, the largest coastal fish farming industry in the world. Farms modified wild fish diets in both quality and quantity, thereby providing farm-associated wild fish with a strong trophic subsidy. This translated to greater somatic (saithe: 1.06-1.12 times; cod: 1.06-1.11 times and liver condition indices (saithe: 1.4-1.8 times; cod: 2.0-2.8 times than control fish caught distant from farms. Parasite loads of farm-associated wild fish were modified from control fish, with increased external and decreased internal parasites, however the strong effect of the trophic subsidy overrode any effects of altered loads upon condition. CONCLUSIONS AND SIGNIFICANCE: Proxy measures of fitness provided no evidence that salmon farms function as ecological traps for wild fish. We suggest fish farms may act as population sources for wild fish, provided they are protected from fishing while resident at farms to allow their increased condition to manifest as greater reproductive output.

Richness patterns in the parasite communities of exotic poeciliid fishes.

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Dove, A D

2000-06-01

Three species of poeciliids (Gambusia holbrooki, Xiphophorus helleri and X. maculatus) and 15 species of ecologically similar native freshwater fishes (mainly eleotrids, ambassids, melanotaeniids and retropinnids) were examined for parasite richness to investigate parasite flux, qualitative differences, quantitative differences and the structuring factors in parasite communities in the 2 fish types in Queensland, Australia. Theory suggests that poeciliids would harbour depauperate parasite communities. Results supported this hypothesis; poeciliids harboured more species-poor parasite infracommunities and regional faunas than natives (P analysis of presence/absence data for poeciliids and the 6 most-sampled native fishes revealed that parasite communities of the 2 fish groups are qualitatively distinct; the proportion of parasite species with complex life-cycles was lower in poeciliids than in native species, and Myxosporea, Microspora, Coccidia and parasitic Crustacea were all absent from poeciliids. Limited exchange of parasite species has occurred between natives and poeciliids. Logistic ordinal regression analysis revealed that fish origin (exotic or native), environmental disturbance and host sex were all significant determinants of parasite community richness (P competitive advantage over native fishes because of their lack of parasites.

A Caenorhabditis elegans wild type defies the temperature-size rule owing to a single nucleotide polymorphism in tra-3.

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Jan E Kammenga

2007-03-01

Full Text Available Ectotherms rely for their body heat on surrounding temperatures. A key question in biology is why most ectotherms mature at a larger size at lower temperatures, a phenomenon known as the temperature-size rule. Since temperature affects virtually all processes in a living organism, current theories to explain this phenomenon are diverse and complex and assert often from opposing assumptions. Although widely studied, the molecular genetic control of the temperature-size rule is unknown. We found that the Caenorhabditis elegans wild-type N2 complied with the temperature-size rule, whereas wild-type CB4856 defied it. Using a candidate gene approach based on an N2 x CB4856 recombinant inbred panel in combination with mutant analysis, complementation, and transgenic studies, we show that a single nucleotide polymorphism in tra-3 leads to mutation F96L in the encoded calpain-like protease. This mutation attenuates the ability of CB4856 to grow larger at low temperature. Homology modelling predicts that F96L reduces TRA-3 activity by destabilizing the DII-A domain. The data show that size adaptation of ectotherms to temperature changes may be less complex than previously thought because a subtle wild-type polymorphism modulates the temperature responsiveness of body size. These findings provide a novel step toward the molecular understanding of the temperature-size rule, which has puzzled biologists for decades.

Testing GxG interactions between coinfecting microbial parasite genotypes within hosts

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Rebecca D Schulte

2014-05-01

Full Text Available Host-parasite interactions represent one of the strongest selection pressures in nature. They are often governed by genotype-specific (GxG interactions resulting in host genotypes that differ in resistance and parasite genotypes that differ in virulence depending on the antagonist’s genotype. Another type of GxG interactions, which is often neglected but which certainly influences host-parasite interactions, are those between coinfecting parasite genotypes. Mechanistically, within-host parasite interactions may range from competition for limited host resources to cooperation for more efficient host exploitation. The exact type of interaction, i.e. whether competitive or cooperative, is known to affect life-history traits such as virulence. However, the latter has been shown for chosen genotype combinations only, not considering whether the specific genotype combination per se may influence the interaction (i.e. GxG interactions. Here, we want to test for the presence of GxG interactions between coinfections of the bacterium Bacillus thuringiensis infecting the nematode Caenorhabditis elegans by combining two non-pathogenic and five pathogenic strains in all possible ways. Furthermore, we evaluate whether the type of interaction, reflected by the direction of virulence change of multiple compared to single infections, is genotype-specific. Generally, we found no indication for GxG interactions between non-pathogenic and pathogenic bacterial strains, indicating that virulence of pathogenic strains is equally affected by both non-pathogenic strains. Specific genotype combinations, however, differ in the strength of virulence change, indicating that the interaction type between coinfecting parasite strains and thus the virulence mechanism is specific for different genotype combinations. Such interactions are expected to influence host-parasite interactions and to have strong implications for coevolution.

Control of acute, chronic, and constitutive hyperammonemia by wild-type and genetically engineered Lactobacillus plantarum in rodents.

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Nicaise, Charles; Prozzi, Deborah; Viaene, Eric; Moreno, Christophe; Gustot, Thierry; Quertinmont, Eric; Demetter, Pieter; Suain, Valérie; Goffin, Philippe; Devière, Jacques; Hols, Pascal

2008-10-01

Hyperammonemia is a common complication of acute and chronic liver diseases. Often accompanied with side effects, therapeutic interventions such as antibiotics or lactulose are generally targeted to decrease the intestinal production and absorption of ammonia. In this study, we aimed to modulate hyperammonemia in three rodent models by administration of wild-type Lactobacillus plantarum, a genetically engineered ammonia hyperconsuming strain, and a strain deficient for the ammonia transporter. Wild-type and metabolically engineered L. plantarum strains were administered in ornithine transcarbamoylase-deficient Sparse-fur mice, a model of constitutive hyperammonemia, in a carbon tetrachloride rat model of chronic liver insufficiency and in a thioacetamide-induced acute liver failure mice model. Constitutive hyperammonemia in Sparse-fur mice and hyperammonemia in a rat model of chronic hepatic insufficiency were efficiently decreased by Lactobacillus administration. In a murine thioacetamide-induced model of acute liver failure, administration of probiotics significantly increased survival and decreased blood and fecal ammonia. The ammonia hyperconsuming strain exhibited a beneficial effect at a lower dose than its wild-type counterpart. Improved survival in the acute liver failure mice model was associated with lower blood ammonia levels but also with a decrease of astrocyte swelling in the brain cortex. Modulation of ammonia was abolished after administration of the strain deficient in the ammonium transporter. Intestinal pH was clearly lowered for all strains and no changes in gut flora were observed. Hyperammonemia in constitutive model or after acute or chronic induced liver failure can be controlled by the administration of L. plantarum with a significant effect on survival. The mechanism involved in this ammonia decrease implicates direct ammonia consumption in the gut.

General anesthetic octanol and related compounds activate wild-type and delF508 cystic fibrosis chloride channels.

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Marcet, Brice; Becq, Frédéric; Norez, Caroline; Delmas, Patrick; Verrier, Bernard

2004-03-01

1. Cystic fibrosis transmembrane conductance regulator (CFTR) Cl(-) channel is defective during cystic fibrosis (CF). Activators of the CFTR Cl(-) channel may be useful for therapy of CF. Here, we demonstrate that a range of general anesthetics like normal-alkanols (n-alkanols) and related compounds can stimulate the Cl(-) channel activity of wild-type CFTR and delF508-CFTR mutant. 2. The effects of n-alkanols like octanol on CFTR activity were measured by iodide ((125)I) efflux and patch-clamp techniques on three distinct cellular models: (1). CFTR-expressing Chinese hamster ovary cells, (2). human airway Calu-3 epithelial cells and (3). human airway JME/CF15 epithelial cells which express the delF508-CFTR mutant. 3. Our data show for the first time that n-alkanols activate both wild-type CFTR and delF508-CFTR mutant. Octanol stimulated (125)I efflux in a dose-dependent manner in CFTR-expressing cells (wild-type and delF508) but not in cell lines lacking CFTR. (125)I efflux and Cl(-) currents induced by octanol were blocked by glibenclamide but insensitive to 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid, as expected for a CFTR Cl(-) current. 4. CFTR activation by octanol was neither due to cell-to-cell uncoupling properties of octanol nor to an intracellular cAMP increase. CFTR activation by octanol requires phosphorylation by protein kinase-A (PKA) since it was prevented by H-89, a PKA inhibitor. 5. n-Alkanols chain length was an important determinant for channel activation, with rank order of potencies: 1-heptanoloctanoloctanol<1-decanol. Our findings may be of valuable interest for developing novel therapeutic strategies for CF.

Synergistic Malaria Parasite Killing by Two Types of Plasmodial Surface Anion Channel Inhibitors.

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Margaret Pain

Full Text Available Malaria parasites increase their host erythrocyte's permeability to a broad range of ions and organic solutes. The plasmodial surface anion channel (PSAC mediates this uptake and is an established drug target. Development of therapies targeting this channel is limited by several problems including interactions between known inhibitors and permeating solutes that lead to incomplete channel block. Here, we designed and executed a high-throughput screen to identify a novel class of PSAC inhibitors that overcome this solute-inhibitor interaction. These new inhibitors differ from existing blockers and have distinct effects on channel-mediated transport, supporting a model of two separate routes for solute permeation though PSAC. Combinations of inhibitors specific for the two routes had strong synergistic action against in vitro parasite propagation, whereas combinations acting on a single route produced only additive effects. The magnitude of synergism depended on external nutrient concentrations, consistent with an essential role of the channel in parasite nutrient acquisition. The identified inhibitors will enable a better understanding of the channel's structure-function and may be starting points for novel combination therapies that produce synergistic parasite killing.

Predictors of Host Specificity among Behavior-Manipulating Parasites

DEFF Research Database (Denmark)

Fredensborg, B. L.

2014-01-01

specifically, hosts’ behavioral modification that involves interaction with the central nervous system presumably restricts parasites to more closely related hosts than does manipulation of the host’s behavior via debilitation of the host’s physiology. The results of the analysis suggest that phylogenetic......-specialist that has a restricted ecological niche that it masters. Parasites that manipulate hosts’ behavior are often thought to represent resource-specialists based on a few spectacular examples of manipulation of the host’s behavior. However, the determinants of which, and how many, hosts a manipulating parasite...... of parasites and hosts. Using individual and multivariate analyses, I examined the effect of the host’s and parasite’s taxonomy, location of the parasite in the host, type of behavioral change, and the effect of debilitation on host-specificity, measured as the mean taxonomic relatedness of hosts...

Systematic strain construction and process development: Xylitol production by Saccharomyces cerevisiae expressing Candida tenuis xylose reductase in wild-type or mutant form.

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Pratter, S M; Eixelsberger, T; Nidetzky, B

2015-12-01

A novel Saccharomyces cerevisiae whole-cell biocatalyst for xylitol production based on Candida tenuis xylose reductase (CtXR) is presented. Six recombinant strains expressing wild-type CtXR or an NADH-specific mutant were constructed and evaluated regarding effects of expression mode, promoter strength, biocatalyst concentration and medium composition. Intracellular XR activities ranged from 0.09 U mgProt(-1) to 1.05 U mgProt(-1) but did not correlate with the strains' xylitol productivities, indicating that other factors limited xylose conversion in the high-activity strains. The CtXR mutant decreased the biocatalyst's performance, suggesting use of the NADPH-preferring wild-type enzyme when (semi-)aerobic conditions are applied. In a bioreactor process, the best-performing strain converted 40 g L(-1) xylose with an initial productivity of 1.16 g L(-1)h(-1) and a xylitol yield of 100%. The obtained results underline the potential of CtXR wild-type for xylose reduction and point out parameters to improve "green" xylitol production. Copyright © 2015 Elsevier Ltd. All rights reserved.

Dietary Calcium and Dairy Modulation of Oxidative Stress and Mortality in aP2-Agouti and Wild-type Mice

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Antje Bruckbauer

2009-08-01

Full Text Available Oxidative and inflammatory stress have been implicated as major contributors to the aging process. Dietary Ca reduced both factors in short-term interventions, while milk exerted a greater effect than supplemental Ca. In this work, we examined the effects of life-long supplemental and dairy calcium on lifespan and life-span related biomarkers in aP2-agouti transgenic (model of diet-induced obesity and wild-type mice fed obesigenic diets until their death. These data demonstrate that dairy Ca exerts sustained effects resulting in attenuated adiposity, protection against age-related muscle loss and reduction of oxidative and inflammatory stress in both mouse strains. Although these effects did not alter maximum lifespan, they did suppress early mortality in wild-type mice, but not in aP2-agouti transgenic mice.

Parasitism, personality and cognition in fish.

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Barber, I; Mora, A B; Payne, E M; Weinersmith, K L; Sih, A

2017-08-01

It is well established that parasites can have profound effects on the behaviour of host organisms, and that individual differences in behaviour can influence susceptibility to parasite infections. Recently, two major themes of research have developed. First, there has been a growing interest in the proximate, mechanistic processes underpinning parasite-associated behaviour change, and the interactive roles of the neuro-, immune, and other physiological systems in determining relationships between behaviour and infection susceptibility. Secondly, as the study of behaviour has shifted away from one-off measurements of single behaviours and towards a behavioural syndromes/personality framework, research is starting to focus on the consequences of parasite infection for temporal and contextual consistency of behaviour, and on the implications of different personality types for infection susceptibility. In addition, there is increasing interest in the potential for relationships between cognition and personality to also have implications for host-parasite interactions. As models well-suited to both the laboratory study of behaviour and experimental parasitology, teleost fish have been used as hosts in many of these studies. In this review we provide a broad overview of the range of mechanisms that potentially generate links between fish behaviour, personality, and parasitism, and illustrate these using examples drawn from the recent literature. In addition, we examine the potential interactions between cognition, personality and parasitism, and identify questions that may be usefully investigated with fish models. Copyright © 2016 Elsevier B.V. All rights reserved.

Comparison of the proteomes of three yeast wild type strains: CEN.PK2, FY1679 and W303

DEFF Research Database (Denmark)

Rogowska-Wrzesinska, A.; Mose Larsen, P.; Blomberg, A.

2001-01-01

Yeast deletion strains created during gene function analysis projects very often show drastic phenotypic differences depending on the genetic background used. These results indicate the existence of important molecular differences between the CEN.PK2, FY1679 and W303 wild type strains...

Lymphotropism and host responses during acute wild-type canine distemper virus infections in a highly susceptible natural host

DEFF Research Database (Denmark)

Nielsen, Line; Søgaard, Mette; Jensen, Trine Hammer

2009-01-01

The mechanisms behind the in vivo virulence of immunosuppressive wild-type Morbillivirus infections are still not fully understood. To investigate lymphotropism and host responses we have selected the natural host model of canine distemper virus (CDV) infection in mink. This model displays...

Effect of deuterium on the circadian period and metabolism in wild-type and tau mutant Syrian hamsters

NARCIS (Netherlands)

Oklejewicz, M; Hut, RA; Daan, S

2000-01-01

Homozygous tau mutant Syrian hamsters (tau-/-) have a free-running circadian period (tau) around 20 h and a proportionally higher metabolic rate compared with wild-type hamsters (tau+/+) with a period of circa 24 h. In this study, we applied deuterium oxide (D2O) to hamsters to test whether

Toxicological significance of soil ingestion by wild and domestic animals

Science.gov (United States)

Beyer, W. Nelson; Fries, George F.; Hoffman, David J.; Rattner, Barnett A.; Burton, G. Allen; Cairns, John

2003-01-01

Most wild and domestic animals ingest some soil or sediment, and some species may routinely, or under special circumstances, ingest considerable amounts. Ingested soil supplies nutrients, exposes animals to parasites and pathogens, and may play a role in developing immune systems.1 Soil ingestion is also sometimes the principal route of exposure to various environmental contaminants.2-7 Ingestion of soil and earthy material is defined as geophagy and may be either intentional or unintentional, occurring as an animal eats or grooms.

Cadmium tolerance, cysteine and thiol peptide levels in wild type and chromium-tolerant strains of Scenedesmus acutus (Chlorophyceae)

Energy Technology Data Exchange (ETDEWEB)

Torricelli, Elena; Gorbi, Gessica; Pawlik-Skowronska, Barbara; Di Toppi, Luigi Sanita; Corradi, Maria Grazia

2004-07-14

Two strains of the unicellular green alga Scenedesmus acutus with different sensitivity to hexavalent chromium were compared for their tolerance of cadmium, by means of growth and recovery tests, and determination of cysteine, reduced glutathione and phytochelatin content, after short-term exposure to various cadmium concentrations (from 1.125 to 27 {mu}M). Growth experiments showed that, after 7-day treatments with cadmium, the chromium-tolerant strain reached a significantly higher cell density and, after 24-h exposure to Cd, was able to resume growth significantly better than the wild type. Constitutive level of cysteine was higher in the chromium-tolerant strain, while glutathione levels were similar in the two strains. The higher content of cysteine and the maintenance of both reduced glutathione and phytochelatin high levels in the presence of cadmium, support the higher cadmium co-tolerance of the chromium-tolerant strain in comparison with the wild type one.

Cadmium tolerance, cysteine and thiol peptide levels in wild type and chromium-tolerant strains of Scenedesmus acutus (Chlorophyceae)

International Nuclear Information System (INIS)

Torricelli, Elena; Gorbi, Gessica; Pawlik-Skowronska, Barbara; Di Toppi, Luigi Sanita; Corradi, Maria Grazia

2004-01-01

Two strains of the unicellular green alga Scenedesmus acutus with different sensitivity to hexavalent chromium were compared for their tolerance of cadmium, by means of growth and recovery tests, and determination of cysteine, reduced glutathione and phytochelatin content, after short-term exposure to various cadmium concentrations (from 1.125 to 27 μM). Growth experiments showed that, after 7-day treatments with cadmium, the chromium-tolerant strain reached a significantly higher cell density and, after 24-h exposure to Cd, was able to resume growth significantly better than the wild type. Constitutive level of cysteine was higher in the chromium-tolerant strain, while glutathione levels were similar in the two strains. The higher content of cysteine and the maintenance of both reduced glutathione and phytochelatin high levels in the presence of cadmium, support the higher cadmium co-tolerance of the chromium-tolerant strain in comparison with the wild type one

Severity of Bovine Tuberculosis Is Associated with Co-Infection with Common Pathogens in Wild Boar

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Risco, David; Serrano, Emmanuel; Fernández-Llario, Pedro; Cuesta, Jesús M.; Gonçalves, Pilar; García-Jiménez, Waldo L.; Martínez, Remigio; Cerrato, Rosario; Velarde, Roser; Gómez, Luis; Segalés, Joaquím; Hermoso de Mendoza, Javier

2014-01-01

Co-infections with parasites or viruses drive tuberculosis dynamics in humans, but little is known about their effects in other non-human hosts. This work aims to investigate the relationship between Mycobacterium bovis infection and other pathogens in wild boar (Sus scrofa), a recognized reservoir of bovine tuberculosis (bTB) in Mediterranean ecosystems. For this purpose, it has been assessed whether contacts with common concomitant pathogens are associated with the development of severe bTB lesions in 165 wild boar from mid-western Spain. The presence of bTB lesions affecting only one anatomic location (cervical lymph nodes), or more severe patterns affecting more than one location (mainly cervical lymph nodes and lungs), was assessed in infected animals. In addition, the existence of contacts with other pathogens such as porcine circovirus type 2 (PCV2), Aujeszky's disease virus (ADV), swine influenza virus, porcine reproductive and respiratory syndrome virus, Mycoplasma hyopneumoniae, Actinobacillus pleuropneumoniae, Haemophilus parasuis and Metastrongylus spp, was evaluated by means of serological, microbiological and parasitological techniques. The existence of contacts with a structured community of pathogens in wild boar infected by M. bovis was statistically investigated by null models. Association between this community of pathogens and bTB severity was examined using a Partial Least Squares regression approach. Results showed that adult wild boar infected by M. bovis had contacted with some specific, non-random pathogen combinations. Contact with PCV2, ADV and infection by Metastrongylus spp, was positively correlated to tuberculosis severity. Therefore, measures against these concomitant pathogens such as vaccination or deworming, might be useful in tuberculosis control programmes in the wild boar. However, given the unexpected consequences of altering any community of organisms, further research should evaluate the impact of such measures under

Severity of bovine tuberculosis is associated with co-infection with common pathogens in wild boar.

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David Risco

Full Text Available Co-infections with parasites or viruses drive tuberculosis dynamics in humans, but little is known about their effects in other non-human hosts. This work aims to investigate the relationship between Mycobacterium bovis infection and other pathogens in wild boar (Sus scrofa, a recognized reservoir of bovine tuberculosis (bTB in Mediterranean ecosystems. For this purpose, it has been assessed whether contacts with common concomitant pathogens are associated with the development of severe bTB lesions in 165 wild boar from mid-western Spain. The presence of bTB lesions affecting only one anatomic location (cervical lymph nodes, or more severe patterns affecting more than one location (mainly cervical lymph nodes and lungs, was assessed in infected animals. In addition, the existence of contacts with other pathogens such as porcine circovirus type 2 (PCV2, Aujeszky's disease virus (ADV, swine influenza virus, porcine reproductive and respiratory syndrome virus, Mycoplasma hyopneumoniae, Actinobacillus pleuropneumoniae, Haemophilus parasuis and Metastrongylus spp, was evaluated by means of serological, microbiological and parasitological techniques. The existence of contacts with a structured community of pathogens in wild boar infected by M. bovis was statistically investigated by null models. Association between this community of pathogens and bTB severity was examined using a Partial Least Squares regression approach. Results showed that adult wild boar infected by M. bovis had contacted with some specific, non-random pathogen combinations. Contact with PCV2, ADV and infection by Metastrongylus spp, was positively correlated to tuberculosis severity. Therefore, measures against these concomitant pathogens such as vaccination or deworming, might be useful in tuberculosis control programmes in the wild boar. However, given the unexpected consequences of altering any community of organisms, further research should evaluate the impact of such measures

Identifying the Integrated Neural Networks Involved in Capsaicin-Induced Pain Using fMRI in Awake TRPV1 Knockout and Wild-Type Rats

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Jason Richard Yee

2015-02-01

Full Text Available In the present study, we used functional MRI in awake rats to investigate the pain response that accompanies intradermal injection of capsaicin into the hindpaw. To this end, we used BOLD imaging together with a 3D segmented, annotated rat atlas and computational analysis to identify the integrated neural circuits involved in capsaicin-induced pain. The specificity of the pain response to capsaicin was tested in a transgenic model that contains a biallelic deletion of the gene encoding for the transient receptor potential cation channel subfamily V member 1 (TRPV1. Capsaicin is an exogenous ligand for the TRPV1 receptor, and in wild-type rats, activated the putative pain neural circuit. In addition, capsaicin-treated wild-type rats exhibited activation in brain regions comprising the Papez circuit and habenular system, systems that play important roles in the integration of emotional information, and learning and memory of aversive information, respectively. As expected, capsaicin administration to TRPV1-KO rats failed to elicit the robust BOLD activation pattern observed in wild-type controls. However, the intradermal injection of formalin elicited a significant activation of the putative pain pathway as represented by such areas as the anterior cingulate, somatosensory cortex, parabrachial nucleus, and periaqueductal gray. Notably, comparison of neural responses to capsaicin in wild-type versus knock-out rats uncovered evidence that capsaicin may function in an antinociceptive capacity independent of TRPV1 signaling. Our data suggest that neuroimaging of pain in awake, conscious animals has the potential to inform the neurobiological basis of full and integrated perceptions of pain.

Role of wild-type p53 in apoptotic and non-apoptotic cell death induced by X-irradiation and heat treatment in p53-mutated mouse M10 cells

International Nuclear Information System (INIS)

Ito, Atsushi; Nakano, Hisako; Shinohara, Kunio

2010-01-01

The sensitizing effects of wild-type p53 on X-ray-induced cell death and on heat-induced apoptosis in M10, a radiosensitive and Trp53 (mouse p53 gene)-mutated lymphoma cell line which dies through necrosis by X-irradiation, were investigated using three M10 derived transfectants with wild-type TP53 (human p53 gene). Cell death was determined by colony formation and/or dye exclusion test, and apoptosis was detected as the changes in nuclear morphology by Giemsa staining. Expression of wild-type p53 protein increased radiosensitivity of cell death as determined by both clonogenic and dye exclusion assays. This increase in radiosensitivity was attributable largely to apoptosis induction in addition to a small enhancement of necrosis. Interestingly neither pathway to cell death was accompanied by caspase-3 activation. On the other hand, heat-induced caspase-3 dependent apoptotic cell death without transfection was further increased by the transfection of wild-type p53. In conclusion, the introduction of wild-type p53 enhanced apoptotic cell death by X-rays or heat via different mechanisms that do or do not activate caspase-3, respectively. In addition, p53 also enhanced the X-ray-induced necrosis in M10 cells. (author)

Plasmodium P-Type Cyclin CYC3 Modulates Endomitotic Growth during Oocyst Development in Mosquitoes.

Science.gov (United States)

Roques, Magali; Wall, Richard J; Douglass, Alexander P; Ramaprasad, Abhinay; Ferguson, David J P; Kaindama, Mbinda L; Brusini, Lorenzo; Joshi, Nimitray; Rchiad, Zineb; Brady, Declan; Guttery, David S; Wheatley, Sally P; Yamano, Hiroyuki; Holder, Anthony A; Pain, Arnab; Wickstead, Bill; Tewari, Rita

2015-11-01

Cell-cycle progression and cell division in eukaryotes are governed in part by the cyclin family and their regulation of cyclin-dependent kinases (CDKs). Cyclins are very well characterised in model systems such as yeast and human cells, but surprisingly little is known about their number and role in Plasmodium, the unicellular protozoan parasite that causes malaria. Malaria parasite cell division and proliferation differs from that of many eukaryotes. During its life cycle it undergoes two types of mitosis: endomitosis in asexual stages and an extremely rapid mitotic process during male gametogenesis. Both schizogony (producing merozoites) in host liver and red blood cells, and sporogony (producing sporozoites) in the mosquito vector, are endomitotic with repeated nuclear replication, without chromosome condensation, before cell division. The role of specific cyclins during Plasmodium cell proliferation was unknown. We show here that the Plasmodium genome contains only three cyclin genes, representing an unusual repertoire of cyclin classes. Expression and reverse genetic analyses of the single Plant (P)-type cyclin, CYC3, in the rodent malaria parasite, Plasmodium berghei, revealed a cytoplasmic and nuclear location of the GFP-tagged protein throughout the lifecycle. Deletion of cyc3 resulted in defects in size, number and growth of oocysts, with abnormalities in budding and sporozoite formation. Furthermore, global transcript analysis of the cyc3-deleted and wild type parasites at gametocyte and ookinete stages identified differentially expressed genes required for signalling, invasion and oocyst development. Collectively these data suggest that cyc3 modulates oocyst endomitotic development in Plasmodium berghei.

Plasmodium P-Type Cyclin CYC3 Modulates Endomitotic Growth during Oocyst Development in Mosquitoes

KAUST Repository

Roques, Magali; Wall, Richard J.; Douglass, Alexander P.; Ramaprasad, Abhinay; Ferguson, David J. P.; Kaindama, Mbinda L.; Brusini, Lorenzo; Joshi, Nimitray; Rchiad, ‍ Zineb; Brady, Declan; Guttery, David S.; Wheatley, Sally P.; Yamano, Hiroyuki; Holder, Anthony A.; Pain, Arnab; Wickstead, Bill; Tewari, Rita

2015-01-01

Cell-cycle progression and cell division in eukaryotes are governed in part by the cyclin family and their regulation of cyclin-dependent kinases (CDKs). Cyclins are very well characterised in model systems such as yeast and human cells, but surprisingly little is known about their number and role in Plasmodium, the unicellular protozoan parasite that causes malaria. Malaria parasite cell division and proliferation differs from that of many eukaryotes. During its life cycle it undergoes two types of mitosis: endomitosis in asexual stages and an extremely rapid mitotic process during male gametogenesis. Both schizogony (producing merozoites) in host liver and red blood cells, and sporogony (producing sporozoites) in the mosquito vector, are endomitotic with repeated nuclear replication, without chromosome condensation, before cell division. The role of specific cyclins during Plasmodium cell proliferation was unknown. We show here that the Plasmodium genome contains only three cyclin genes, representing an unusual repertoire of cyclin classes. Expression and reverse genetic analyses of the single Plant (P)-type cyclin, CYC3, in the rodent malaria parasite, Plasmodium berghei, revealed a cytoplasmic and nuclear location of the GFP-tagged protein throughout the lifecycle. Deletion of cyc3 resulted in defects in size, number and growth of oocysts, with abnormalities in budding and sporozoite formation. Furthermore, global transcript analysis of the cyc3-deleted and wild type parasites at gametocyte and ookinete stages identified differentially expressed genes required for signalling, invasion and oocyst development. Collectively these data suggest that cyc3 modulates oocyst endomitotic development in Plasmodium berghei.

Plasmodium P-Type Cyclin CYC3 Modulates Endomitotic Growth during Oocyst Development in Mosquitoes

Science.gov (United States)

Ferguson, David J. P.; Kaindama, Mbinda L.; Brusini, Lorenzo; Joshi, Nimitray; Rchiad, Zineb; Brady, Declan; Guttery, David S.; Wheatley, Sally P.; Yamano, Hiroyuki; Holder, Anthony A.; Pain, Arnab; Wickstead, Bill; Tewari, Rita

2015-01-01

Cell-cycle progression and cell division in eukaryotes are governed in part by the cyclin family and their regulation of cyclin-dependent kinases (CDKs). Cyclins are very well characterised in model systems such as yeast and human cells, but surprisingly little is known about their number and role in Plasmodium, the unicellular protozoan parasite that causes malaria. Malaria parasite cell division and proliferation differs from that of many eukaryotes. During its life cycle it undergoes two types of mitosis: endomitosis in asexual stages and an extremely rapid mitotic process during male gametogenesis. Both schizogony (producing merozoites) in host liver and red blood cells, and sporogony (producing sporozoites) in the mosquito vector, are endomitotic with repeated nuclear replication, without chromosome condensation, before cell division. The role of specific cyclins during Plasmodium cell proliferation was unknown. We show here that the Plasmodium genome contains only three cyclin genes, representing an unusual repertoire of cyclin classes. Expression and reverse genetic analyses of the single Plant (P)-type cyclin, CYC3, in the rodent malaria parasite, Plasmodium berghei, revealed a cytoplasmic and nuclear location of the GFP-tagged protein throughout the lifecycle. Deletion of cyc3 resulted in defects in size, number and growth of oocysts, with abnormalities in budding and sporozoite formation. Furthermore, global transcript analysis of the cyc3-deleted and wild type parasites at gametocyte and ookinete stages identified differentially expressed genes required for signalling, invasion and oocyst development. Collectively these data suggest that cyc3 modulates oocyst endomitotic development in Plasmodium berghei. PMID:26565797

Plasmodium P-Type Cyclin CYC3 Modulates Endomitotic Growth during Oocyst Development in Mosquitoes

KAUST Repository

Roques, Magali

2015-11-13

Cell-cycle progression and cell division in eukaryotes are governed in part by the cyclin family and their regulation of cyclin-dependent kinases (CDKs). Cyclins are very well characterised in model systems such as yeast and human cells, but surprisingly little is known about their number and role in Plasmodium, the unicellular protozoan parasite that causes malaria. Malaria parasite cell division and proliferation differs from that of many eukaryotes. During its life cycle it undergoes two types of mitosis: endomitosis in asexual stages and an extremely rapid mitotic process during male gametogenesis. Both schizogony (producing merozoites) in host liver and red blood cells, and sporogony (producing sporozoites) in the mosquito vector, are endomitotic with repeated nuclear replication, without chromosome condensation, before cell division. The role of specific cyclins during Plasmodium cell proliferation was unknown. We show here that the Plasmodium genome contains only three cyclin genes, representing an unusual repertoire of cyclin classes. Expression and reverse genetic analyses of the single Plant (P)-type cyclin, CYC3, in the rodent malaria parasite, Plasmodium berghei, revealed a cytoplasmic and nuclear location of the GFP-tagged protein throughout the lifecycle. Deletion of cyc3 resulted in defects in size, number and growth of oocysts, with abnormalities in budding and sporozoite formation. Furthermore, global transcript analysis of the cyc3-deleted and wild type parasites at gametocyte and ookinete stages identified differentially expressed genes required for signalling, invasion and oocyst development. Collectively these data suggest that cyc3 modulates oocyst endomitotic development in Plasmodium berghei.

Spatial encoding in spinal sensorimotor circuits differs in different wild type mice strains

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Schouenborg Jens

2008-05-01

Full Text Available Abstract Background Previous studies in the rat have shown that the spatial organisation of the receptive fields of nociceptive withdrawal reflex (NWR system are functionally adapted through experience dependent mechanisms, termed somatosensory imprinting, during postnatal development. Here we wanted to clarify 1 if mice exhibit a similar spatial encoding of sensory input to NWR as previously found in the rat and 2 if mice strains with a poor learning capacity in various behavioural tests, associated with deficient long term potention, also exhibit poor adaptation of NWR. The organisation of the NWR system in two adult wild type mouse strains with normal long term potentiation (LTP in hippocampus and two adult wild type mouse strains exhibiting deficiencies in corresponding LTP were used and compared to previous results in the rat. Receptive fields of reflexes in single hindlimb muscles were mapped with CO2 laser heat pulses. Results While the spatial organisation of the nociceptive receptive fields in mice with normal LTP were very similar to those in rats, the LTP impaired strains exhibited receptive fields of NWRs with aberrant sensitivity distributions. However, no difference was found in NWR thresholds or onset C-fibre latencies suggesting that the mechanisms determining general reflex sensitivity and somatosensory imprinting are different. Conclusion Our results thus confirm that sensory encoding in mice and rat NWR is similar, provided that mice strains with a good learning capability are studied and raise the possibility that LTP like mechanisms are involved in somatosensory imprinting.

The role of rare innate immune cells in Type 2 immune activation against parasitic helminths.

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Webb, Lauren M; Tait Wojno, Elia D

2017-09-01

The complexity of helminth macroparasites is reflected in the intricate network of host cell types that participate in the Type 2 immune response needed to battle these organisms. In this context, adaptive T helper 2 cells and the Type 2 cytokines interleukin (IL)-4, IL-5, IL-9 and IL-13 have been the focus of research for years, but recent work has demonstrated that the innate immune system plays an essential role. Some innate immune cells that promote Type 2 immunity are relatively abundant, such as macrophages and eosinophils. However, we now appreciate that more rare cell types including group 2 innate lymphoid cells, basophils, mast cells and dendritic cells make significant contributions to these responses. These cells are found at low frequency but they are specialized to their roles - located at sites such as the skin, lung and gut, where the host combats helminth parasites. These cells respond rapidly and robustly to worm antigens and worm-induced damage to produce essential cytokines, chemokines, eicosanoids and histamine to activate damaged epithelium and to recruit other effectors. Thus, a greater understanding of how these cells operate is essential to understand how the host protects itself during helminth infection.

Wild cyclic voles maintain high neutral and MHC diversity without strong evidence for parasite-mediated selection

Czech Academy of Sciences Publication Activity Database

Winternitz, Jamie Caroline; Wares, J. P.; Yabsley, M. J.; Altizer, S.

2014-01-01

Roč. 28, č. 5 (2014), s. 957-975 ISSN 0269-7653 Institutional support: RVO:68081766 Keywords : Major histocompatibility complex * Host-parasite relationship * Balancing selection * Microtus montanus * Cestodes * Eimeria * Microsatellites Subject RIV: EG - Zoology Impact factor: 2.517, year: 2014

Parasites in the Wadden Sea food web

Science.gov (United States)

Thieltges, David W.; Engelsma, Marc Y.; Wendling, Carolin C.; Wegner, K. Mathias

2013-09-01

While the free-living fauna of the Wadden Sea has received much interest, little is known on the distribution and effects of parasites in the Wadden Sea food web. However, recent studies on this special type of trophic interaction indicate a high diversity of parasites in the Wadden Sea and suggest a multitude of effects on the hosts. This also includes effects on specific predator-prey relationships and the general structure of the food web. Focussing on molluscs, a major group in the Wadden Sea in terms of biomass and abundance and an important link between primary producers and predators, we review existing studies and exemplify the ecological role of parasites in the Wadden Sea food web. First, we give a brief inventory of parasites occurring in the Wadden Sea, ranging from microparasites (e.g. protozoa, bacteria) to macroparasites (e.g. helminths, parasitic copepods) and discuss the effects of spatial scale on heterogeneities in infection levels. We then demonstrate how parasites can affect host population dynamics by acting as a strong mortality factor, causing mollusc mass mortalities. In addition, we will exemplify how parasites can mediate the interaction strength of predator-prey relationships and affect the topological structure of the Wadden Sea food web as a whole. Finally, we highlight some ongoing changes regarding parasitism in the Wadden Sea in the course of global change (e.g. species introduction, climate change) and identify important future research questions to entangle the role of parasites in the Wadden Sea food web.

Explaining the resurgent popularity of the wild: motivations for wild plant gathering in the Biosphere Reserve Grosses Walsertal, Austria.

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Schunko, Christoph; Grasser, Susanne; Vogl, Christian R

2015-06-30

Wild plant gathering becomes again a popular and fashionable activity in Europe after gathering practices have been increasingly abandoned over the last decades. Recent ethnobotanical research documented a diversity of gathering practices from people of diverse socio-economic and cultural backgrounds who gather in urban and rural areas. Few efforts were though made to study the motivations for gathering wild plants and to understand the resurgent popularity of wild plant gathering. This paper addresses the following research questions: (1) which motivations activate wild plant gatherers? (2) which motivation-types of gatherers exist in the Grosses Walsertal? (3) how do the motivations for gathering relate to the socio-demographic background of gatherers? Field research was conducted in the Grosses Walsertal, Austria in the years 2008 and 2009 in two field research periods. Thirty-six local farmers were first interviewed with semi-structured interviews. The motivations identified in these interviews were then included in a structured questionnaire, which was used to interview 353 residents of the valley. Pupils of local schools participated in the data collection as interviewers. Principal Component Analysis was used to categorize the motivations and to identify motivation-types of wild plant gatherers. Generalized Linear Models were calculated to identify relations between motivations and the socio-demographic background of gatherers. The respondents listed 13 different motivations for gathering wild plants and four motivations for not gathering. These 17 motivations were grouped in five motivation-types of wild plant gatherers, which are in decreasing importance: product quality, fun, tradition, not-gathering, income. Women, older respondents and homegardeners gather wild plants more often for fun; older respondents gather more often for maintaining traditions; non-homegardeners more frequently mention motivations for not gathering. The resurgent popularity of

[Hemoparasites in wild birds in Madagascar].

Science.gov (United States)

Raharimanga, V; Soula, F; Raherilalao, M J; Goodman, S M; Sadonès, H; Tall, A; Randrianarivelojosia, M; Raharimalala, L; Duchemin, J B; Ariey, F; Robert, V

2002-01-01

This study aims to evaluate the prevalence and density of haemoparasites in native Malagasy birds. Among the 387 birds, belonging to 43 species sampled at six localities in different bio-climatic zones of the island, 139 (35.9%) showed at least 1 hemoparasite with, by order of frequency, Plasmodium and/or Haemoproteus (19.9%), microfilariae (13.7% of 387 birds), Leucocytozoon (11.1%) and Trypanosoma (1.0%). An analysis to further elucidate these observations took into account the interaction of different environmental variables (altitude, season, site of collection) or aspects of the birds (age, weight, sex). There is evidence that some parasites preferentially infect some bird species or families. The largest male birds harboured the highest prevalences and densities of haemoparasite, regardless of species. These findings extend knowledge of bird/blood parasite relationships of Malagasy birds and provide interesting insights, especially concerning the pathogenicity of this type of parasitism and the parasite transmission by insect vectors.

The evolution of cuckoo parasitism: a comparative analysis.

Science.gov (United States)

Krüger, O; Davies, N B

2002-02-22

Cuckoos (family Cuculidae) show the highest diversity of breeding strategies within one bird family (parental care, facultative and obligate brood parasites). We used independent contrasts from two phylogenies to examine how this variation was related to 13 ecological and life-history variables. The ancestral state was probably tropical, resident, forest cuckoos with parental care. The evolution of brood parasitism was correlated with a shift to more open habitats, a change in diet, increases in species breeding-range size and migration, and a decrease in egg size. Once parasitism had evolved, more elaborate parasitic strategies (more harmful to host fitness) were correlated with decreased egg size, a change in diet, increased breeding-range size and migration, a shortened breeding season and a decrease in local abundance. Establishing the most probable evolutionary pathways, using the method of Pagel, shows that changes in ecological variables (such as migration, range size and diet type) preceded the evolution of brood parasitism, which is likely to be a later adaptation to reduce the cost of reproduction. By contrast, brood parasitism evolved before changes in egg size occurred, indicating that egg size is an adaptive trait in host--parasite coevolution. Our results suggest that the evolution of cuckoo brood parasitism reflects selection from both ecological pressures and host defences.

Anopheles moucheti and Anopheles vinckei are candidate vectors of ape Plasmodium parasites, including Plasmodium praefalciparum in Gabon.

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Christophe Paupy

Full Text Available During the last four years, knowledge about the diversity of Plasmodium species in African great apes has considerably increased. Several new species were described in chimpanzees and gorillas, and some species that were previously considered as strictly of human interest were found to be infecting African apes. The description in gorillas of P. praefalciparum, the closest relative of P. falciparum which is the main malignant agent of human malaria, definitively changed the way we understand the evolution and origin of P. falciparum. This parasite is now considered to have appeared recently, following a cross-species transfer from gorillas to humans. However, the Plasmodium vector mosquito species that have served as bridge between these two host species remain unknown. In order to identify the vectors that ensure ape Plasmodium transmission and evaluate the risk of transfer of these parasites to humans, we carried out a field study in Gabon to capture Anopheles in areas where wild and semi-wild ape populations live. We collected 1070 Anopheles females belonging to 15 species, among which An. carnevalei, An. moucheti and An. marshallii were the most common species. Using mtDNA-based PCR tools, we discovered that An. moucheti, a major human malaria vector in Central Africa, could also ensure the natural transmission of P. praefalciparum among great apes. We also showed that, together with An. vinckei, An. moucheti was infected with P. vivax-like parasites. An. moucheti constitutes, therefore, a major candidate for the transfer of Plasmodium parasites from apes to humans.

Photomorphogenic responses to UV radiation III: a comparative study of UVB effects on anthocyanin and flavonoid accumulation in wild-type and aurea mutant of tomato (Lycopersicon esculentum Mill.)

International Nuclear Information System (INIS)

Brandt, K.; Giannini, A.; Lercari, B.

1995-01-01

The UV-mediated induction of anthocyanin and UV-absorbing compounds was characterized in etiolated hypocotyls of wild-type and aurea (au) mutant tomato seedlings. Ultraviolet radiation induced significant increases of anthocyanin and UV-absorbing compounds in hypocotyls of the au mutant and of its isogenic wild-type, but the differences in the time courses of UV-induced pigment accumulation indicate that different photoregulatory mechanisms are involved for each of these two groups of pigments. It appears that prolonged presence of adequate levels of UVB (290-320 nm) energy and consequently the action of a specific UVB photoreceptor are indispensable for the photoinduction of anthocyanin accumulation in UV-irradiated hypocotyl of the au mutant that is missing the labile phytochrome pool. The large difference found between the wild-type and the au mutant strongly indicate the involvement of labile phytochrome as the primary functional photoreceptor for the photoinduction of anthocyanin accumulation in wild-type tomato hypocotyls. (author)

Hepatozoon ellisgreineri n. sp. (Hepatozoidae): description of the first avian apicomplexan blood parasite inhabiting granulocytes.

Science.gov (United States)

Valkiūnas, Gediminas; Mobley, Kristin; Iezhova, Tatjana A

2016-02-01

Blood parasites of the genus Hepatozoon (Apicomplexa, Hepatozoidae) infect all groups of terrestrial vertebrates, and particularly high prevalence and species diversity have been reported in reptiles and mammals. A few morphologically similar species, in which gamonts inhabit mononuclear leukocytes and red blood cells, have been described in birds. Here, we report a new Hepatozoon species, which was found in wild-caught secretary birds Sagittarius serpentarius, from Tanzania. Hepatozoon ellisgreineri n. sp. can be readily distinguished from all described species of avian Hepatozoon because its gamonts develop only in granulocytes, predominantly in heterophils, a unique characteristic among bird parasites of this genus. Additionally, this is the first reported avian apicomplexan blood parasite, which inhabits and matures in granulocytes. We describe H. ellisgreineri based on morphological characteristics of blood stages and their host cells. This finding broadens knowledge about host cells of avian Hepatozoon spp. and other avian apicomplexan blood parasites, contributing to the better understanding of the diversity of haematozoa. This is the first report of hepatozoonosis in endangered African birds of the Sagittariidae.

Coprological study of gastrointestinal parasites of captive animals at Rangpur Recreational Garden and Zoo in Bangladesh

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M.M. Khatun

2014-07-01

Full Text Available A survey was undertaken to investigate the prevalence of gastrointestinal parasites in different groups of mammals housed at Rangpur Recreational Garden and Zoo in Bangladesh. A total of 45 fecal samples of different animals (11 carnivores, 26 herbivores and 8 primates were examined from April to September 2011 for the presence of gastrointestinal parasites. The overall prevalence of parasitic infection was 60% (27/45 of which 35.6% (16/45 were helminth infections and 24% (11/45 were protozoic infections. The identified parasites included protozoa (Balantidium coli and Coccidia sp., nematodes (Toxascaris leonina, Toxocara cati, Strongyloides sp., Dictyocaulus sp., Trichuris sp. and stomach worm, cestodes (Spirometra sp. and Moniezia benedeni and trematodes (Fasciola sp.. At least one parasite was identified in the fecal samples of all animals except of the samples from bear, python, water buck and olive baboon. Mixed infections were observed in Rhesus monkey (Trichuris sp. and Balantidium coli, in deer (Strongyloides sp. and Coccidia sp. and in lion (Toxascaris leonina and Spirometra sp.. Helminth infections were more common than protozoic infections in carnivores and herbivores, whereas in primates, protozoic infections were more common than helminth infections. The high prevalence of gastrointestinal parasites found in zoo animals in this study emphasizes the importance of controlling these parasitic infections in order to safeguard the health of housed wild animals and of the humans working with these animals.

Gastrointestinal helminths of two populations of wild pigeons (Columba livia in Brazil

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Frederico Fontanelli Vaz

Full Text Available Abstract The present study analyzed gastrointestinal helminth communities in 265 wild pigeons (Columba livia living in the municipalities of São Paulo and Tatuí, state of São Paulo, Brazil, over a one-year period. The birds were caught next to grain storage warehouses and were necropsied. A total of 790 parasites comprising one nematode species and one cestode genus were recovered from 110 pigeons, thus yielding an overall prevalence of 41.5%, mean intensity of infection of 7.2 ± 1.6 (range 1-144 and discrepancy index of 0.855. Only 15 pigeons (5.7% presented mixed infection. The helminths isolated from the birds were Ascaridia columbae (Ascaridiidae and Raillietina sp. (Davaineidae. The birds’ weights differed according to sex but this did not influence the intensity of infection. The overall prevalence and intensity of infection did not differ between the sexes, but the prevalence was higher among the birds from Tatuí (47.8%. The gastrointestinal helminth community of C. livia was characterized in the two areas studied and parasite homogeneity was observed over the 12 months analyzed at both locations. These results make contributions to the current literature on health aspects of wild C. livia populations.

RNA mobility in parasitic plant – host interactions

Science.gov (United States)

Kim, Gunjune

2017-01-01

ABSTRACT The parasitic plant Cuscuta exchanges mRNAs with its hosts. Systemic mobility of mRNAs within plants is well documented, and has gained increasing attention as studies using grafted plant systems have revealed new aspects of mobile mRNA regulation and function. But parasitic plants take this phenomenon to a new level by forming seamless connections to a wide range of host species, and raising questions about how mRNAs might function after transfer to a different species. Cuscuta and other parasitic plant species also take siRNAs from their hosts, indicating that multiple types of RNA are capable of trans-specific movement. Parasitic plants are intriguing systems for studying RNA mobility, in part because such exchange opens new possibilities for control of parasitic weeds, but also because they provide a fresh perspective into understanding roles of RNAs in inter-organismal communication. PMID:28277936

Striga parasitizes transgenic hairy roots of Zea mays and provides a tool for studying plant-plant interactions

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Runo Steven

2012-06-01

Full Text Available Abstract Background Striga species are noxious root hemi-parasitic weeds that debilitate cereal production in sub-Saharan Africa (SSA. Control options for Striga are limited and developing Striga resistant crop germplasm is regarded as the best and most sustainable control measure. Efforts to improve germplasm for Striga resistance by a non-Genetic Modification (GM approach, for example by exploiting natural resistance, or by a GM approach are constrained by limited information on the biological processes underpinning host-parasite associations. Additionaly, a GM approach is stymied by lack of availability of candidate resistance genes for introduction into hosts and robust transformation methods to validate gene functions. Indeed, a majority of Striga hosts, the world’s most cultivated cereals, are recalcitrant to genetic transformation. In maize, the existing protocols for transformation and regeneration are tedious, lengthy, and highly genotype-specific with low efficiency of transformation. Results We used Agrobacterium rhizogenes strain K599 carrying a reporter gene construct, Green Fluorescent Protein (GFP, to generate transgenic composite maize plants that were challenged with the parasitic plant Striga hermonthica. Eighty five percent of maize plants produced transgenic hairy roots expressing GFP. Consistent with most hairy roots produced in other species, transformed maize roots exhibited a hairy root phenotype, the hallmark of A. rhizogenes mediated transformation. Transgenic hairy roots resulting from A. rhizogenes transformation were readily infected by S. hermonthica. There were no significant differences in the number and size of S. hermonthica individuals recovered from either transgenic or wild type roots. Conclusions This rapid, high throughput, transformation technique will advance our understanding of gene function in parasitic plant-host interactions.

Extracellular enzyme activities during lignocellulose degradation by Streptomyces spp.: a comparative study of wild-type and genetically manipulated strains

International Nuclear Information System (INIS)

Ramachandra, M.; Crawford, D.L.; Pometto, A.L. III

1987-01-01

The wild-type ligninolytic actinomycete Streptomyces viridosporus T7A and two genetically manipulated strains with enhanced abilities to produce a water-soluble lignin degradation intermediate, an acid-precipitable polymeric lignin (APPL), were grown on lignocellulose in solid-state fermentation cultures. Culture filtrates were periodically collected, analyzed for APPL, and assayed for extracellular lignocellulose-catabolizing enzyme activities. Two APPL-overproducing strains, UV irradiation mutant T7A-81 and protoplast fusion recombinant SR-10, had higher and longer persisting peroxidase, esterase, and endoglucanase activities than did the wild-type strain T7A. Results implicated one or more of these enzymes in lignin solubilization. Only mutant T7A-81 had higher xylanase activity than the wild type. The peroxidase was induced by both lignocellulose and APPL. This extracellular enzyme has some similarities to previously described ligninases in fungi. This is the first report of such an enzyme in Streptomyces spp. Four peroxidase isozymes were present, and all catalyzed the oxidation of 3,4-dihydroxyphenylalanine, while one also catalyzed hydrogen peroxide-dependent oxidation of homoprotocatechuic acid and caffeic acid. Three constitutive esterase isozymes were produced which differed in substrate specificity toward α-naphthyl acetate and α-naphthyl butyrate. Three endoglucanase bands, which also exhibited a low level of xylanase activity, were identified on polyacrylamide gels as was one xylanase-specific band. There were no major differences in the isoenzymes produced by the different strains. The probable role of each enzyme in lignocellulose degradation is discussed

Status of gastrointestinal parasites in Red Panda of Nepal.

Science.gov (United States)

Bista, Damber; Shrestha, Saroj; Kunwar, Ajaya Jang; Acharya, Sakshi; Jnawali, Shant Raj; Acharya, Krishna Prasad

2017-01-01

Red pandas are known to be highly susceptible to endoparasites, which can have a prominent impact on the population dynamics of this endangered species. There are very limited published reports on prevalence and risk of parasites in wild populations of red panda, especially localized reports. This study attempts to provide an in-depth insight of the status of endoparasites in red pandas, which is critical for strengthening conservation efforts. A total of 272 fecal samples were collected through systematic sampling across the red panda distribution range in Nepal and coprological examination was completed using standard techniques. It was followed by an estimation of prevalence and mean intensity of parasites, as well as statistical analysis, which was carried out using R statistical software. Parasite prevalence was documented in 90.80% ( n  = 247) out of 272 samples examined which includes seven different species along with three genera of parasites belonging to Protozoans (3 species), Cestodes (1 genus, 1 species) and Nematodes (2 genera, 3 species). Nematodes predominated in all infected samples (87.62%). Prevalence of Ancyclostoma duodenale ( n  = 227, 70.06%), having a mean intensity of 3.45 ± 2.88 individuals per sample, was observed, followed by Ascaris lumbricoides ( n  = 19, 5.86%) and Entamoeba histolytica ( n  = 24, 7.41%). Eight variables for assessing the determinants of infestation were tested: protected areas; non-protected areas; aspect; elevation; slope; and distance to water sources, herding stations, and settlements. Only the settlement displayed significant association ( β = -1534e-04, t  =  - 2.192, p  = 0.0293) though each parasite species displayed dissimilar association with different variables. This study indicates the urgent need of improving existing herding practice through habitat zonation, rotational grazing, medication of livestock, and prohibition of open defecation within and around red panda habitat.

Chimpanzee malaria parasites related to Plasmodium ovale in Africa.

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Linda Duval

Full Text Available Since the 1970's, the diversity of Plasmodium parasites in African great apes has been neglected. Surprisingly, P. reichenowi, a chimpanzee parasite, is the only such parasite to have been molecularly characterized. This parasite is closely phylogenetically related to P. falciparum, the principal cause of the greatest malaria burden in humans. Studies of malaria parasites from anthropoid primates may provide relevant phylogenetic information, improving our understanding of the origin and evolutionary history of human malaria species. In this study, we screened 130 DNA samples from chimpanzees (Pan troglodytes and gorillas (Gorilla gorilla from Cameroon for Plasmodium infection, using cytochrome b molecular tools. Two chimpanzees from the subspecies Pan t. troglodytes presented single infections with Plasmodium strains molecularly related to the human malaria parasite P. ovale. These chimpanzee parasites and 13 human strains of P. ovale originated from a various sites in Africa and Asia were characterized using cytochrome b and cytochrome c oxidase 1 mitochondrial partial genes and nuclear ldh partial gene. Consistent with previous findings, two genetically distinct types of P. ovale, classical and variant, were observed in the human population from a variety of geographical locations. One chimpanzee Plasmodium strain was genetically identical, on all three markers tested, to variant P. ovale type. The other chimpanzee Plasmodium strain was different from P. ovale strains isolated from humans. This study provides the first evidence of possibility of natural cross-species exchange of P. ovale between humans and chimpanzees of the subspecies Pan t. troglodytes.

Characteristics of alpha/beta interferon induction after infection of murine fibroblasts with wild-type and mutant alphaviruses

International Nuclear Information System (INIS)

Burke, Crystal W.; Gardner, Christina L.; Steffan, Joshua J.; Ryman, Kate D.; Klimstra, William B.

2009-01-01

We examined the characteristics of interferon alpha/beta (IFN-α/β) induction after alphavirus or control Sendai virus (SeV) infection of murine fibroblasts (MEFs). As expected, SeV infection of wild-type (wt) MEFs resulted in strong dimerization of IRF3 and the production of high levels of IFN-α/β. In contrast, infection of MEFs with multiple alphaviruses failed to elicit detectable IFN-α/β. In more detailed studies, Sindbis virus (SINV) infection caused dimerization and nuclear migration of IRF3, but minimal IFN-β promoter activity, although surprisingly, the infected cells were competent for IFN production by other stimuli early after infection. A SINV mutant defective in host macromolecular synthesis shutoff induced IFN-α/β in the MEF cultures dependent upon the activities of the TBK1 IRF3 activating kinase and host pattern recognition receptors (PRRs) PKR and MDA5 but not RIG-I. These results suggest that wild-type alphaviruses antagonize IFN induction after IRF3 activation but also may avoid detection by host PRRs early after infection.

Ecology of the gastrointestinal parasites of Colobus vellerosus at Boabeng-Fiema, Ghana: possible anthropozoonotic transmission.

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Teichroeb, Julie A; Kutz, Susan J; Parkar, Unaiza; Thompson, R C Andrew; Sicotte, Pascale

2009-11-01

Parasite richness and prevalence in wild animals can be used as indicators of population and ecosystem health. In this study, the gastrointestinal parasites of ursine colobus monkeys (Colobus vellerosus) at the Boabeng-Fiema Monkey Sanctuary (BFMS), Ghana, were investigated. BFMS is a sacred grove where monkeys and humans have long lived in relatively peaceful proximity. Fecal samples (n = 109) were collected opportunistically from >27 adult and subadult males in six bisexual groups and one all-male band from July 2004 to August 2005. Using fecal floatation, we detected three protozoans (two Entamoeba sp., Isospora sp.), five nematodes (Ascaris sp., Enterobius sp., Trichuris sp., two strongyle sp.), and one digenean trematode. Using fluorescein labeled antibodies, we detected an additional protozoan (Giardia sp.), and with PCR techniques, we characterized this as G. duodenalis Assemblage B and also identified a protistan (Blastocystis sp., subtype 2). The most prevalent parasite species were G. duodenalis and Trichuris sp. Parasites were more prevalent in the long wet season than the long dry. Parasite prevalence did not vary by age, and average parasite richness did not differ by rank for males whose status remained unchanged. However, males that changed rank tended to show higher average parasite richness when they were lower ranked. Individuals that spent more time near human settlements had a higher prevalence of Isospora sp. that morphologically resembled the human species I. belli. The presence of this parasite and G. duodenalis Assemblage B indicates possible anthropozoonotic and/or zoonotic transmission between humans and colobus monkeys at this site.

Small rodents as paratenic or intermediate hosts of carnivore parasites in Berlin, Germany.

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Krücken, Jürgen; Blümke, Julia; Maaz, Denny; Demeler, Janina; Ramünke, Sabrina; Antolová, Daniela; Schaper, Roland; von Samson-Himmelstjerna, Georg

2017-01-01

Rodents are important intermediate and paratenic hosts for carnivore parasites, including the important zoonotic agents Toxoplasma, Echinococcus and Toxocara. Monitoring of such parasites in rodents can be used to detect increasing risks for human and veterinary public health. Rodents were trapped at four sites in Berlin, two near the city center, two at the periphery. PCRs were conducted to detect Coccidia (target ITS-1) and specifically Toxoplasma gondii (repetitive element) in brain and ascarids (ITS-2) in muscle or brain tissue. During necropsies, metacestodes were collected and identified using ITS-2 and 12S rRNA PCRs. An ELISA to detect antibodies against Toxocara canis ES antigens was performed. Within the 257 examined rodents, the most frequently observed parasite was Frenkelia glareoli predominantly found in Myodes glareolus. T. gondii was only detected in 12 rodents and Microtus spp. (although strongly underrepresented) had a significantly increased chance of being positive. Neither Echinococcus nor typical Taenia parasites of dogs and cats were found but Mesocestoides litteratus and Taenia martis metacestodes were identified which can cause severe peritoneal or ocular cysticercosis in dogs, primates and humans. Using PCR, the ascarids T. canis (n = 8), Toxocara cati (4) and Parascaris sp. (1) were detected predominantly in muscles. Seroprevalence of T. canis was 14.2% and ELISA was thus more sensitive than PCR to detect infection with this parasite. Non-parametric multidimensional scaling and cluster analysis revealed that parasite communities could be grouped into an urban and a peri-urban cluster with high frequency of ascarid-positive rodents in urban and high frequency of F. glareoli in peri-urban sites. Prevalence rates of parasites in rodents with potential impact for human or veterinary public health are considerable and the monitoring of transmission cycles of carnivore parasites in intermediate rodent hosts is recommended to estimate the health

Small rodents as paratenic or intermediate hosts of carnivore parasites in Berlin, Germany.

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Jürgen Krücken

Full Text Available Rodents are important intermediate and paratenic hosts for carnivore parasites, including the important zoonotic agents Toxoplasma, Echinococcus and Toxocara. Monitoring of such parasites in rodents can be used to detect increasing risks for human and veterinary public health. Rodents were trapped at four sites in Berlin, two near the city center, two at the periphery. PCRs were conducted to detect Coccidia (target ITS-1 and specifically Toxoplasma gondii (repetitive element in brain and ascarids (ITS-2 in muscle or brain tissue. During necropsies, metacestodes were collected and identified using ITS-2 and 12S rRNA PCRs. An ELISA to detect antibodies against Toxocara canis ES antigens was performed. Within the 257 examined rodents, the most frequently observed parasite was Frenkelia glareoli predominantly found in Myodes glareolus. T. gondii was only detected in 12 rodents and Microtus spp. (although strongly underrepresented had a significantly increased chance of being positive. Neither Echinococcus nor typical Taenia parasites of dogs and cats were found but Mesocestoides litteratus and Taenia martis metacestodes were identified which can cause severe peritoneal or ocular cysticercosis in dogs, primates and humans. Using PCR, the ascarids T. canis (n = 8, Toxocara cati (4 and Parascaris sp. (1 were detected predominantly in muscles. Seroprevalence of T. canis was 14.2% and ELISA was thus more sensitive than PCR to detect infection with this parasite. Non-parametric multidimensional scaling and cluster analysis revealed that parasite communities could be grouped into an urban and a peri-urban cluster with high frequency of ascarid-positive rodents in urban and high frequency of F. glareoli in peri-urban sites. Prevalence rates of parasites in rodents with potential impact for human or veterinary public health are considerable and the monitoring of transmission cycles of carnivore parasites in intermediate rodent hosts is recommended to

Helminth parasites of cats from the Vientiane Province, Laos, as indicators of the occurrence of causative agents of human parasitoses

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Scholz T.

2003-12-01

Full Text Available A total of 55 domestic cats (Felis calus f. domestico and one wild (Bengal cat (Prionailurus bengalensis from the Vientiane Province, central Laos, were examined for helminth parasites with emphasis given to potential human parasites. The following species were found (parasites infective to man marked with an asterisk: Opisthorchis viverrini*, Haplorchis pumilio*,H. laichui*,H. yokogawai*, Stellantchasmus falcatus* (Digenea; Spirometra sp.*, Dipylidium caninum*, Taenia taeniaeformis (Cestoda; Capillariidae gen. sp., Toxocara canis*, T. cati*, Ancylostoma ceylanicum*, A. tubaeforme, Gnathostoma spinigerum*, Physaloptera preputials (Nematoda; and Oncicola sp. (Acanthocephala. This study demonstrated that examination of cats may provide useful data on the occurrence of helminths which are potential causative agents of human diseases.

EvoWild: a demosimulator about wild life

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Eduardo Palacio Gayoso

2008-12-01

Full Text Available During the last years we can see how AI (Artificial Intelligence is reappearing because of technological improvements. These improvements make possible the management of large groups of information with acceptable reply times.On the other hand, cost reductions in technology make possible that an investigation field like AI becomes to an inversion field closer to scale economies, that’s why it’ll be economically profitable to invert in this type of applications.One of the fastest consequences is the AI implantation in a big amount of devices of our environment, cell telephones, palms and of course, in the video game industry.This is the reason that took us to develop EvoWild, a simulation about wild life that has video game format and tools but at the same time implements AI algorithms like genetic algorithms and reasoning based in cases.

Comparative metabolic profiling of mce1 operon mutant vs wild-type Mycobacterium tuberculosis strains.

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Queiroz, Adriano; Medina-Cleghorn, Daniel; Marjanovic, Olivera; Nomura, Daniel K; Riley, Lee W

2015-11-01

Mycobacterium tuberculosis disrupted in a 13-gene operon (mce1) accumulates free mycolic acids (FM) in its cell wall and causes accelerated death in mice. Here, to more comprehensively analyze differences in their cell wall lipid composition, we used an untargeted metabolomics approach to compare the lipid profiles of wild-type and mce1 operon mutant strains. By liquid chromatography-mass spectrometry, we identified >400 distinct lipids significantly altered in the mce1 mutant compared to wild type. These lipids included decreased levels of saccharolipids and glycerophospholipids, and increased levels of alpha-, methoxy- and keto mycolic acids (MA), and hydroxyphthioceranic acid. The mutant showed reduced expression of mmpL8, mmpL10, stf0, pks2 and papA2 genes involved in transport and metabolism of lipids recognized to induce proinflammatory response; these lipids were found to be decreased in the mutant. In contrast, the transcripts of mmpL3, fasI, kasA, kasB, acpM and RV3451 involved in MA transport and metabolism increased; MA inhibits inflammatory response in macrophages. Since the mce1 operon is known to be regulated in intracellular M. tuberculosis, we speculate that the differences we observed in cell wall lipid metabolism and composition may affect host response to M. tuberculosis infection and determine the clinical outcome of such an infection. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Beyond T and DHT - novel steroid derivatives capable of wild type androgen receptor activation.

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Mostaghel, Elahe A

2014-01-01

While androgen deprivation therapy (ADT) remains the primary treatment for metastatic prostate cancer (PCa), castration does not eliminate androgens from the prostate tumor microenvironment, and residual intratumoral androgens are implicated in nearly every mechanism by which androgen receptor (AR)-mediated signaling promotes castration-resistant disease. The uptake and intratumoral (intracrine) conversion of circulating adrenal androgens such as dehydroepiandrosterone sulfate (DHEA-S) to steroids capable of activating the wild type AR is a recognized driver of castration resistant prostate cancer (CRPC). However, less well-characterized adrenal steroids, including 11-deoxcorticosterone (DOC) and 11beta-hydroxyandrostenedione (11OH-AED) may also play a previously unrecognized role in promoting AR activation. In particular, recent data demonstrate that the 5α-reduced metabolites of DOC and 11OH-AED are activators of the wild type AR. Given the well-recognized presence of SRD5A activity in CRPC tissue, these observations suggest that in the low androgen environment of CRPC, alternative sources of 5α-reduced ligands may supplement AR activation normally mediated by the canonical 5α-reduced agonist, 5α-DHT. Herein we review the emerging data that suggests a role for these alternative steroids of adrenal origin in activating the AR, and discuss the enzymatic pathways and novel downstream metabolites mediating these effects. We conclude by discussing the potential implications of these findings for CRPC progression, particularly in context of new agents such as abiraterone and enzalutamide which target the AR-axis for prostate cancer therapy.

Action potentials and ion conductances in wild-type and CALHM1-knockout type II taste cells

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Saung, Wint Thu; Foskett, J. Kevin

2017-01-01

Taste bud type II cells fire action potentials in response to tastants, triggering nonvesicular ATP release to gustatory neurons via voltage-gated CALHM1-associated ion channels. Whereas CALHM1 regulates mouse cortical neuron excitability, its roles in regulating type II cell excitability are unknown. In this study, we compared membrane conductances and action potentials in single identified TRPM5-GFP-expressing circumvallate papillae type II cells acutely isolated from wild-type (WT) and Calhm1 knockout (KO) mice. The activation kinetics of large voltage-gated outward currents were accelerated in cells from Calhm1 KO mice, and their associated nonselective tail currents, previously shown to be highly correlated with ATP release, were completely absent in Calhm1 KO cells, suggesting that CALHM1 contributes to all of these currents. Calhm1 deletion did not significantly alter resting membrane potential or input resistance, the amplitudes and kinetics of Na+ currents either estimated from action potentials or recorded from steady-state voltage pulses, or action potential threshold, overshoot peak, afterhyperpolarization, and firing frequency. However, Calhm1 deletion reduced the half-widths of action potentials and accelerated the deactivation kinetics of transient outward currents, suggesting that the CALHM1-associated conductance becomes activated during the repolarization phase of action potentials. NEW & NOTEWORTHY CALHM1 is an essential ion channel component of the ATP neurotransmitter release mechanism in type II taste bud cells. Its contribution to type II cell resting membrane properties and excitability is unknown. Nonselective voltage-gated currents, previously associated with ATP release, were absent in cells lacking CALHM1. Calhm1 deletion was without effects on resting membrane properties or voltage-gated Na+ and K+ channels but contributed modestly to the kinetics of action potentials. PMID:28202574

Genetic diversity of wild and hatchery lake trout populations: Relevance for management and restoration in the Great Lakes

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Page, K.S.; Scribner, K.T.; Burnham-Curtis, M.

2004-01-01

The biological diversity of lake trout Salvelinus namaycush in the upper Great Lakes was historically high, consisting of many recognizable morphological types and discrete spawning populations. During the 1950s and 1960s, lake trout populations were extirpated from much of the Great Lakes primarily as a result of overfishing and predation by the parasitic sea lamprey Petromyzon marinus. Investigations of how genetic diversity is partitioned among remnant wild lake trout populations and hatchery broodstocks have been advocated to guide lake trout management and conservation planning. Using microsatellite genetic markers, we estimated measures of genetic diversity and the apportionment of genetic variance among 6 hatchery broodstocks and 10 wild populations representing three morphotypes (lean, humper, and siscowet). Analyses revealed that different hatchery broodstocks and wild populations contributed disproportionally to the total levels of genetic diversity. The genetic affinities of hatchery lake trout reflected the lake basins of origin of the wild source populations. The variance in allele frequency over all sampled extant wild populations was apportioned primarily on the basis of morphotype (??MT = 0.029) and secondarily among geographically dispersed populations within each morphotype (??ST = 0.024). The findings suggest that the genetic divergence reflected in recognized morphotypes and the associated ecological and physiological specialization occurred prior to the partitioning of large proglacial lakes into the Great Lakes or as a consequence of higher contemporary levels of gene flow within than among morphotypes. Information on the relative contributions of different broodstocks to total gene diversity within the regional hatchery program can be used to prioritize the broodstocks to be retained and to guide future stocking strategies. The findings highlight the importance of ecological and phenotypic diversity in Great Lakes fish communities and

Identification of enzymes and quantification of metabolic fluxes in the wild type and in a recombinant Aspergillus oryzae strain

DEFF Research Database (Denmark)

Pedersen, Henrik; Carlsen, Morten; Nielsen, Jens Bredal

1999-01-01

Two alpha-amylase-producing strains of Aspergillus oryzae, a wild-type strain and a recombinant containing additional copies of the alpha-amylase gene, were characterized,vith respect to enzyme activities, localization of enzymes to the mitochondria or cytosol, macromolecular composition...

Paternal spatial training enhances offspring's cognitive performance and synaptic plasticity in wild-type but not improve memory deficit in Alzheimer's mice.

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Zhang, Shujuan; Li, Xiaoguang; Wang, Zhouyi; Liu, Yanchao; Gao, Yuan; Tan, Lu; Liu, Enjie; Zhou, Qiuzhi; Xu, Cheng; Wang, Xin; Liu, Gongping; Chen, Haote; Wang, Jian-Zhi

2017-05-08

Recent studies suggest that spatial training can maintain associative memory capacity in Tg2576 mice, but it is not known whether the beneficial effects can be inherited from the trained fathers to their offspring. Here, we exposed male wild-type and male 3XTg Alzheimer disease (AD) mice (3-m old) respectively to spatial training for one week and assessed the transgenerational effects in the F1 offspring when they were grown to 7-m old. We found that the paternal spatial training significantly enhanced progeny's spatial cognitive performance and synaptic transmission in wild-type mice. Among several synapse- or memory-associated proteins, we observed that the expression level of synaptotagmin 1 (SYT1) was significantly increased in the hippocampus of the paternally trained-offspring. Paternal training increased histone acetylation at the promoter of SYT1 in both fathers' and the offspring's hippocampus, and as well as in the fathers' sperm. Finally, paternal spatial training for one week did not improve memory and synaptic plasticity in 3XTg AD F1 offspring. Our findings suggest paternal spatial training for one week benefits the offspring's cognitive performance in wild-type mice with the mechanisms involving an enhanced transgenerational histone acetylation at SYT1 promoter.

Differential inhibition of ex-vivo tumor kinase activity by vemurafenib in BRAF(V600E and BRAF wild-type metastatic malignant melanoma.

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Andliena Tahiri

Full Text Available Treatment of metastatic malignant melanoma patients harboring BRAF(V600E has improved drastically after the discovery of the BRAF inhibitor, vemurafenib. However, drug resistance is a recurring problem, and prognoses are still very bad for patients harboring BRAF wild-type. Better markers for targeted therapy are therefore urgently needed.In this study, we assessed the individual kinase activity profiles in 26 tumor samples obtained from patients with metastatic malignant melanoma using peptide arrays with 144 kinase substrates. In addition, we studied the overall ex-vivo inhibitory effects of vemurafenib and sunitinib on kinase activity status.Overall kinase activity was significantly higher in lysates from melanoma tumors compared to normal skin tissue. Furthermore, ex-vivo incubation with both vemurafenib and sunitinib caused significant decrease in phosphorylation of kinase substrates, i.e kinase activity. While basal phosphorylation profiles were similar in BRAF wild-type and BRAF(V600E tumors, analysis with ex-vivo vemurafenib treatment identified a subset of 40 kinase substrates showing stronger inhibition in BRAF(V600E tumor lysates, distinguishing the BRAF wild-type and BRAF(V600E tumors. Interestingly, a few BRAF wild-type tumors showed inhibition profiles similar to BRAF(V600E tumors. The kinase inhibitory effect of vemurafenib was subsequently analyzed in cell lines harboring different BRAF mutational status with various vemurafenib sensitivity in-vitro.Our findings suggest that multiplex kinase substrate array analysis give valuable information about overall tumor kinase activity. Furthermore, intra-assay exposure to kinase inhibiting drugs may provide a useful tool to study mechanisms of resistance, as well as to identify predictive markers.

Use of tissue-specific microRNA to control pathology of wild-type adenovirus without attenuation of its ability to kill cancer cells.

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Cawood, Ryan; Chen, Hannah H; Carroll, Fionnadh; Bazan-Peregrino, Miriam; van Rooijen, Nico; Seymour, Leonard W

2009-05-01

Replicating viruses have broad applications in biomedicine, notably in cancer virotherapy and in the design of attenuated vaccines; however, uncontrolled virus replication in vulnerable tissues can give pathology and often restricts the use of potent strains. Increased knowledge of tissue-selective microRNA expression now affords the possibility of engineering replicating viruses that are attenuated at the RNA level in sites of potential pathology, but retain wild-type replication activity at sites not expressing the relevant microRNA. To assess the usefulness of this approach for the DNA virus adenovirus, we have engineered a hepatocyte-safe wild-type adenovirus 5 (Ad5), which normally mediates significant toxicity and is potentially lethal in mice. To do this, we have included binding sites for hepatocyte-selective microRNA mir-122 within the 3' UTR of the E1A transcription cassette. Imaging versions of these viruses, produced by fusing E1A with luciferase, showed that inclusion of mir-122 binding sites caused up to 80-fold decreased hepatic expression of E1A following intravenous delivery to mice. Animals administered a ten-times lethal dose of wild-type Ad5 (5x10(10) viral particles/mouse) showed substantial hepatic genome replication and extensive liver pathology, while inclusion of 4 microRNA binding sites decreased replication 50-fold and virtually abrogated liver toxicity. This modified wild-type virus retained full activity within cancer cells and provided a potent, liver-safe oncolytic virus. In addition to providing many potent new viruses for cancer virotherapy, microRNA control of virus replication should provide a new strategy for designing safe attenuated vaccines applied across a broad range of viral diseases.

Toxoplasma gondii, source to sea: higher contribution of domestic felids to terrestrial parasite loading despite lower infection prevalence.

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Vanwormer, Elizabeth; Conrad, Patricia A; Miller, Melissa A; Melli, Ann C; Carpenter, Tim E; Mazet, Jonna A K

2013-09-01

Environmental transmission of Toxoplasma gondii, a global zoonotic parasite, adversely impacts human and animal health. Toxoplasma is a significant cause of mortality in threatened Southern sea otters, which serve as sentinels for disease threats to people and animals in coastal environments. As wild and domestic felids are the only recognized hosts capable of shedding Toxoplasma oocysts into the environment, otter infection suggests land-to-sea pathogen transmission. To assess relative contributions to terrestrial parasite loading, we evaluated infection and shedding among managed and unmanaged feral domestic cats, mountain lions, and bobcats in coastal California, USA. Infection prevalence differed among sympatric felids, with a significantly lower prevalence for managed feral cats (17%) than mountain lions, bobcats, or unmanaged feral cats subsisting on wild prey (73-81%). A geographic hotspot of infection in felids was identified near Monterey Bay, bordering a high-risk site for otter infection. Increased odds of oocyst shedding were detected in bobcats and unmanaged feral cats. Due to their large populations, pet and feral domestic cats likely contribute more oocysts to lands bordering the sea otter range than native wild felids. Continued coastal development may influence felid numbers and distribution, increase terrestrial pathogens in freshwater runoff, and alter disease dynamics at the human-animal-environment interface.

Wild-type and A315T mutant TDP-43 exert differential neurotoxicity in a Drosophila model of ALS

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Estes, Patricia S.; Boehringer, Ashley; Zwick, Rebecca; Tang, Jonathan E.; Grigsby, Brianna; Zarnescu, Daniela C.

2011-01-01

The RNA-binding protein TDP-43 has been linked to amyotrophic lateral sclerosis (ALS) both as a causative locus and as a marker of pathology. With several missense mutations being identified within TDP-43, efforts have been directed towards generating animal models of ALS in mouse, zebrafish, Drosophila and worms. Previous loss of function and overexpression studies have shown that alterations in TDP-43 dosage recapitulate hallmark features of ALS pathology, including neuronal loss and locomotor dysfunction. Here we report a direct in vivo comparison between wild-type and A315T mutant TDP-43 overexpression in Drosophila neurons. We found that when expressed at comparable levels, wild-type TDP-43 exerts more severe effects on neuromuscular junction architecture, viability and motor neuron loss compared with the A315T allele. A subset of these differences can be compensated by higher levels of A315T expression, indicating a direct correlation between dosage and neurotoxic phenotypes. Interestingly, larval locomotion is the sole parameter that is more affected by the A315T allele than wild-type TDP-43. RNA interference and genetic interaction experiments indicate that TDP-43 overexpression mimics a loss-of-function phenotype and suggest a dominant-negative effect. Furthermore, we show that neuronal apoptosis does not require the cytoplasmic localization of TDP-43 and that its neurotoxicity is modulated by the proteasome, the HSP70 chaperone and the apoptosis pathway. Taken together, our findings provide novel insights into the phenotypic consequences of the A315T TDP-43 missense mutation and suggest that studies of individual mutations are critical for elucidating the molecular mechanisms of ALS and related neurodegenerative disorders. PMID:21441568

Toxoplasma gondii antibody prevalence and two new genotypes of the parasite in endangered Hawaiian Geese (nene: Branta sandvicensis)

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Work, Thierry M.; Verma, Shiv K.; Su, Chunlei; Medeiros, John; Kaiakapu, Thomas; Kwok, Oliver C.; Dubey, Jitender P.

2016-01-01

Toxoplasma gondii is a protozoan parasite transmitted by domestic cats (Felis catus) that has historically caused mortality in native Hawaiian birds. To estimate how widespread exposure to the parasite is in nene (Hawaiian Geese, Branta sandvicensis), we did a serologic survey for T. gondii antibody and genetically characterized parasite DNA from the tissues of dead birds that had confirmed infections by immunohistochemistry. Of 94 geese sampled, prevalence on the island of Kauai, Maui, and Molokai was 21% (n=42), 23% (n=31), and 48% (n=21), respectively. Two new T. gondii genotypes were identified by PCR-restriction fragment length polymorphism from four geese, and these appeared segregated geographically. Exposure to T. gondii in wild nene is widespread and, while the parasite is not a major cause of death, it could have sublethal or behavioral effects. How to translate such information to implement effective ways to manage feral cats in Hawaii poses challenges.

Helminths parasitizing larval fish from Pantanal, Brazil.

Science.gov (United States)

Lacerda, A C F; Santin, M; Takemoto, R M; Pavanelli, G C; Bialetzki, A; Tavernari, F C

2009-03-01

Fish larvae of 'corvinas' (Pachyurus bonariensis and Plagioscion ternetzi) from Sinhá Mariana Lagoon, Mato Grosso State, were collected from March 2000 to March 2004, in order to determine the parasitic fauna of fishes. Larvae from the two species were parasitized by the same endoparasites: Contracaecum sp. Type 2 (larvae) (Nematoda: Anisakidae) in the mesentery and Neoechinorhynchus (Neoechinorhynchus) paraguayensis (Acanthocephala: Neoechinorhynchidae) in the stomach and the terminal portion of the intestine. Statistical analysis showed that there was a significant positive correlation between the standard length of hosts and the abundance of acanthocephalans and nematodes, and that the prevalence of nematodes presented a significant positive correlation with the standard length of the two species of hosts, indicating the presence of a cumulative process of infection. The present study constitutes the first record of nematodes and acanthocephalans parasitizing larval fish, as well as the first record of endoparasites in fish larvae in Brazil. In addition, it lists a new locality and two species of hosts for Contracaecum sp. Type 2 (larva) and N. (N.) paraguayensis.

Host Mitochondrial Association Evolved in the Human Parasite Toxoplasma gondii via Neofunctionalization of a Gene Duplicate.

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Adomako-Ankomah, Yaw; English, Elizabeth D; Danielson, Jeffrey J; Pernas, Lena F; Parker, Michelle L; Boulanger, Martin J; Dubey, Jitender P; Boyle, Jon P

2016-05-01

In Toxoplasma gondii, an intracellular parasite of humans and other animals, host mitochondrial association (HMA) is driven by a gene family that encodes multiple mitochondrial association factor 1 (MAF1) proteins. However, the importance of MAF1 gene duplication in the evolution of HMA is not understood, nor is the impact of HMA on parasite biology. Here we used within- and between-species comparative analysis to determine that the MAF1 locus is duplicated in T. gondii and its nearest extant relative Hammondia hammondi, but not another close relative, Neospora caninum Using cross-species complementation, we determined that the MAF1 locus harbors multiple distinct paralogs that differ in their ability to mediate HMA, and that only T. gondii and H. hammondi harbor HMA(+) paralogs. Additionally, we found that exogenous expression of an HMA(+) paralog in T. gondii strains that do not normally exhibit HMA provides a competitive advantage over their wild-type counterparts during a mouse infection. These data indicate that HMA likely evolved by neofunctionalization of a duplicate MAF1 copy in the common ancestor of T. gondii and H. hammondi, and that the neofunctionalized gene duplicate is selectively advantageous. Copyright © 2016 by the Genetics Society of America.

What can social parasites tell us about cooperation and conflict in insect societies?

DEFF Research Database (Denmark)

Nash, David Richard

strategies to exploit social insect colonies. Both types of social parasitism can provide useful insights into cooperation and conflict within insect societies. Closely related social parasites are essentially the outcome of the breakdown of cooperation and the realisation of conflict, and the unique...... to examine how cooperation can be exploited independent of these traits. In this presentation I will examine both types of social parasitism in detail, and provide some examples of the insights they can bring to the study of cooperation and conflict....

MT-PCR panel detection of canine parvovirus (CPV-2): Vaccine and wild-type CPV-2 can be difficult to differentiate in canine diagnostic fecal samples.

Science.gov (United States)

Meggiolaro, Maira N; Ly, Anna; Rysnik-Steck, Benjamin; Silva, Carolina; Zhang, Joshua; Higgins, Damien P; Muscatello, Gary; Norris, Jacqueline M; Krockenberger, Mark; Šlapeta, Jan

2017-06-01

Canine parvovirus (CPV-2) remains an important cause of devastating enteritis in young dogs. It can be successfully prevented with live attenuated CPV-2 vaccines when given at the appropriate age and in the absence of maternal antibody interference. Rapid diagnosis of parvoviral enteritis in young dogs is essential to ensuring suitable barrier nursing protocols within veterinary hospitals. The current diagnostic trend is to use multiplexed PCR panels to detect an array of pathogens commonly responsible for diarrhea in dogs. The multiplexed PCR assays do not distinguish wild from vaccine CPV-2. They are highly sensitive and detect even a low level of virus shedding, such as those caused by the CPV-2 vaccine. The aim of this study was to identify the CPV-2 subtypes detected in diagnostic specimens and rule out occult shedding of CPV-2 vaccine strains. For a total of 21 samples that tested positive for CPV-2 in a small animal fecal pathogens diagnostic multiplexed tandem PCR (MT-PCR) panel during 2014-2016 we partially characterized the VP2 gene of CPV-2. Vaccine CPV-2 strain, wild type CPV-2a subtypes and vaccine-like CPV-2b subtypes were detected. High copy number was indicative of wild-type CPV-2a presence, but presence of vaccine-like CPV-2b had a variable copy number in fecal samples. A yardstick approach to a copy number or C t -value to discriminate vaccine strain from a wild type virus of CPV-2 can be, in some cases, potentially misleading. Therefore, discriminating vaccine strain from a wild type subtype of CPV-2 remains ambitious. Copyright © 2017 Elsevier Ltd. All rights reserved.

Screening and Expression of a Silicon Transporter Gene (Lsi1) in Wild-Type Indica Rice Cultivars

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Abiri, Rambod; Kalhori, Nahid; Atabaki, Narges

2017-01-01

Silicon (Si) is one of the most prevalent elements in the soil. It is beneficial for plant growth and development, and it contributes to plant defense against different stresses. The Lsi1 gene encodes a Si transporter that was identified in a mutant Japonica rice variety. This gene was not identified in fourteen Malaysian rice varieties during screening. Then, a mutant version of Lsi1 was substituted for the native version in the three most common Malaysian rice varieties, MR219, MR220, and MR276, to evaluate the function of the transgene. Real-time PCR was used to explore the differential expression of Lsi1 in the three transgenic rice varieties. Silicon concentrations in the roots and leaves of transgenic plants were significantly higher than in wild-type plants. Transgenic varieties showed significant increases in the activities of the enzymes SOD, POD, APX, and CAT; photosynthesis; and chlorophyll content; however, the highest chlorophyll A and B levels were observed in transgenic MR276. Transgenic varieties have shown a stronger root and leaf structure, as well as hairier roots, compared to the wild-type plants. This suggests that Lsi1 plays a key role in rice, increasing the absorption and accumulation of Si, then alters antioxidant activities, and improves morphological properties. PMID:28191468

Screening and Expression of a Silicon Transporter Gene (Lsi1 in Wild-Type Indica Rice Cultivars

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Mahbod Sahebi

2017-01-01

Full Text Available Silicon (Si is one of the most prevalent elements in the soil. It is beneficial for plant growth and development, and it contributes to plant defense against different stresses. The Lsi1 gene encodes a Si transporter that was identified in a mutant Japonica rice variety. This gene was not identified in fourteen Malaysian rice varieties during screening. Then, a mutant version of Lsi1 was substituted for the native version in the three most common Malaysian rice varieties, MR219, MR220, and MR276, to evaluate the function of the transgene. Real-time PCR was used to explore the differential expression of Lsi1 in the three transgenic rice varieties. Silicon concentrations in the roots and leaves of transgenic plants were significantly higher than in wild-type plants. Transgenic varieties showed significant increases in the activities of the enzymes SOD, POD, APX, and CAT; photosynthesis; and chlorophyll content; however, the highest chlorophyll A and B levels were observed in transgenic MR276. Transgenic varieties have shown a stronger root and leaf structure, as well as hairier roots, compared to the wild-type plants. This suggests that Lsi1 plays a key role in rice, increasing the absorption and accumulation of Si, then alters antioxidant activities, and improves morphological properties.

Screening and Expression of a Silicon Transporter Gene (Lsi1) in Wild-Type Indica Rice Cultivars.

Science.gov (United States)

Sahebi, Mahbod; Hanafi, Mohamed M; Rafii, M Y; Azizi, Parisa; Abiri, Rambod; Kalhori, Nahid; Atabaki, Narges

2017-01-01

Silicon (Si) is one of the most prevalent elements in the soil. It is beneficial for plant growth and development, and it contributes to plant defense against different stresses. The Lsi1 gene encodes a Si transporter that was identified in a mutant Japonica rice variety. This gene was not identified in fourteen Malaysian rice varieties during screening. Then, a mutant version of Lsi1 was substituted for the native version in the three most common Malaysian rice varieties, MR219, MR220, and MR276, to evaluate the function of the transgene. Real-time PCR was used to explore the differential expression of Lsi1 in the three transgenic rice varieties. Silicon concentrations in the roots and leaves of transgenic plants were significantly higher than in wild-type plants. Transgenic varieties showed significant increases in the activities of the enzymes SOD, POD, APX, and CAT; photosynthesis; and chlorophyll content; however, the highest chlorophyll A and B levels were observed in transgenic MR276. Transgenic varieties have shown a stronger root and leaf structure, as well as hairier roots, compared to the wild-type plants. This suggests that Lsi1 plays a key role in rice, increasing the absorption and accumulation of Si, then alters antioxidant activities, and improves morphological properties.

Screening for Indian isolates of egg-parasitic fungi for use in biological control of fascioliasis and amphistomiasis in ruminant livestock.

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De, S; Sanyal, P K; Sarkar, A K; Patel, N K; Pal, S; Mandal, S C

2008-09-01

Wild isolates of the egg-parasitic fungi Paecilomyces lilacinus and Verticillium chlamydosporium, obtained from the organic environment of Durg, Chhattisgarh, India, were subjected to screening for in vitro growth using different media types, range of incubation temperature and pH, and their predatory activity to the eggs of Fasciola gigantica and Gigantocotyle explanatum. Maximum growth of P. lilacinus was obtained in corn-meal agar compared to any other media types. The preferred medium for growth of V. chlamydosporium was corn-meal agar, followed by potato-dextrose agar. After initial growth for 16 h of incubation, no growth was observed in water agar for both the fungi. Six different temperatures--4 degrees C, 10 degrees C, 18 degrees C, 26 degrees C, 34 degrees C and 40 degrees C--were used to observe growth profiles of the fungi in corn-meal agar medium. While no and very little growth of P. lilacinus and V. chlamydosporium was observed at 4 degrees C and 10 degrees C, respectively, growth profiles of both the fungi were optimal at 26-40 degrees C. A range of pH (pH 4-8) supported growth of both P. lilacinus and V. chlamydosporium. Full-grown plates of the fungi baited with viable eggs of F. gigantica and G. explanatum revealed that V. chlamydosporium was more vigorous in its egg-parasitic ability compared to P. lilacinus. Distortion of the eggs started on day 2-3 of egg baiting in culture plates of V. chlamydosporium, with complete distortion by day 7. On the contrary, P. lilacinus exhibited very limited egg-parasitic ability and some of the baited eggs even showed development of miracidia.

Lysogenic Streptococcus suis isolate SS2-4 containing prophage SMP showed increased mortality in zebra fish compared to the wild-type isolate.

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Fang Tang

Full Text Available Streptococcus suis (S. suis infection is considered to be a major problem in the swine industry worldwide. Based on the capsular type, 33 serotypes of S. suis have been described, with serotype 2 (SS2 being the most frequently isolated from diseased piglets. Little is known, however, about the pathogenesis and virulence factors of S. suis. Research on bacteriophages highlights a new area in S. suis research. A S. suis serotype 2 bacteriophage, designated SMP, has been previously isolated in our laboratory. Here, we selected a lysogenic isolate in which the SMP phage was integrated into the chromosome of strain SS2-4. Compared to the wild-type isolate, the lysogenic strain showed increased mortality in zebra fish. Moreover the sensitivity of the lysogenic strain to lysozyme was seven times higher than that of the wild-type.

Environmental Surveillance System To Track Wild Poliovirus Transmission

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Deshpande, Jagadish M.; Shetty, Sushmitha J.; Siddiqui, Zaeem A.

2003-01-01

Eradication of poliomyelitis from large metropolis cities in India has been difficult due to high population density and the presence of large urban slums. Three paralytic poliomyelitis cases were reported in Mumbai, India, in 1999 and 2000 in spite of high immunization coverage and good-quality supplementary immunization activities. We therefore established a systematic environmental surveillance study by weekly screening of sewage samples from three high-risk slum areas to detect the silent transmission of wild poliovirus. In 2001, from among the 137 sewage samples tested, wild poliovirus type 1 was isolated from 35 and wild poliovirus type 3 was isolated from 1. Acute flaccid paralysis (AFP) surveillance indicated one case of paralytic poliomyelitis from the city. Phylogenetic analysis with complete VP1 sequences revealed that the isolates from environmental samples belonged to four lineages of wild polioviruses recently isolated from poliomyelitis cases in Uttar Pradesh and not to those previously isolated from AFP cases in Mumbai. Wild poliovirus thus introduced caused one case of paralytic poliomyelitis. The virus was detected in environmental samples 3 months before. It was found that wild polioviruses introduced several times during the year circulated in Mumbai for a limited period before being eliminated. Environmental surveillance was found to be sensitive for the detection of wild poliovirus silent transmission. Nucleotide sequence analysis helped identify wild poliovirus reservoir areas. PMID:12732567

Wild and domesticated mushroom consumption in Nigeria ...

African Journals Online (AJOL)

African Crop Science Journal ... On the other hand, if nutrition analysis reveals different nutrition parameters for both types of mushrooms, 43.3% opted for cultivated mushroom, 42.2%, wild; 12.2% both; while 2.2% would eat ... Keywords: Consumption pattern, Lentinus squarrosulus, nutrition, perception, wild mushroom ...

Haemosporidian parasite infections in grouse and ptarmigan: Prevalence and genetic diversity of blood parasites in resident Alaskan birds

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Smith, Matthew M.; Van Hemert, Caroline R.; Merizon, Richard

2016-01-01

Projections related to future climate warming indicate the potential for an increase in the distribution and prevalence of blood parasites in northern regions. However, baseline data are lacking for resident avian host species in Alaska. Grouse and ptarmigan occupy a diverse range of habitat types throughout the northern hemisphere and are among the most well-known and important native game birds in North America. Information regarding the prevalence and diversity of haemosporidian parasites in tetraonid species is limited, with few recent studies and an almost complete lack of genetic data. To better understand the genetic diversity of haemosporidian parasites in Alaskan tetraonids and to determine current patterns of geographic range and host specificity, we used molecular methods to screen 459 tissue samples collected from grouse and ptarmigan species across multiple regions of Alaska for infection by Leucocytozoon, Haemoproteus, and Plasmodium blood parasites. Infections were detected in 342 individuals, with overall apparent prevalence of 53% for Leucocytozoon, 21% for Haemoproteus, and 9% for Plasmodium. Parasite prevalence varied by region, with different patterns observed between species groups (grouse versus ptarmigan). Leucocytozoon was more common in ptarmigan, whereas Haemoproteus was more common in grouse. We detected Plasmodium infections in grouse only. Analysis of haemosporidian mitochondrial DNA cytochrome b sequences revealed 23 unique parasite haplotypes, several of which were identical to lineages previously detected in other avian hosts. Phylogenetic analysis showed close relationships between haplotypes from our study and those identified in Alaskan waterfowl for Haemoproteus and Plasmodium parasites. In contrast, Leucocytozoon lineages were structured strongly by host family. Our results provide some of the first genetic data for haemosporidians in grouse and ptarmigan species, and provide an initial baseline on the prevalence and diversity

Multidisciplinary re-description of Plasmodium (Novyella) paranucleophilum in Brazilian wild birds of the Atlantic Forest kept in captivity.

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Tostes, Raquel; Dias, Roberto Júnio Pedroso; Martinele, Isabel; Senra, Marcus Vinicius Xavier; D'Agosto, Marta; Massard, Carlos Luiz

2017-07-01

Haemosporidian blood parasites of the Plasmodium genus are the causative agents of avian malaria in many parts of the world. Despite the great diversity of Brazilian avifauna, few studies have been conducted to examine the haemosporidians of wild birds found in the Brazilian Atlantic Forest, especially those kept in captivity. This study aimed to re-examine and further characterize the South American avian parasite Plasmodium paranucleophilum using a multidisciplinary approach. Blood samples were collected from 68 captive birds representing 15 species found in the Atlantic Forest of southeastern Brazil. Morphometric and morphological characterization was performed, in addition to PCR and sequencing of the mitochondrial cytochrome b gene and subsequent phylogenetic analysis. The overall prevalence of P. paranucleophilum infection in the study was 13.23% (n = 9), with a mean parasitemia of 0.58%. We observed the highest parasitemia of 3.88% in Rupornis magnirostris. In our phylogenetic analysis, P. paranucleophilum and P lasmodium nucleophilum formed distinct, highly supported clades, with a mean genetic divergence of 2.48%. This study provides new morphological and molecular data, expanding our knowledge of the haemosporidians of wild birds in Brazil and highlighting the need for further investigation. The true depth of diversity in Brazilian avian haemosporidians remains largely unknown, and given the enormous variety of vectors and avian species, there may be many more species of these blood parasites yet to be described.

Engineering of red cells of Arabidopsis thaliana and comparative genome-wide gene expression analysis of red cells versus wild-type cells.

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Shi, Ming-Zhu; Xie, De-Yu

2011-04-01

We report metabolic engineering of Arabidopsis red cells and genome-wide gene expression analysis associated with anthocyanin biosynthesis and other metabolic pathways between red cells and wild-type (WT) cells. Red cells of A. thaliana were engineered for the first time from the leaves of production of anthocyanin pigment 1-Dominant (pap1-D). These red cells produced seven anthocyanin molecules including a new one that was characterized by LC-MS analysis. Wild-type cells established as a control did not produce anthocyanins. A genome-wide microarray analysis revealed that nearly 66 and 65% of genes in the genome were expressed in the red cells and wild-type cells, respectively. In comparison with the WT cells, 3.2% of expressed genes in the red cells were differentially expressed. The expression levels of 14 genes involved in the biosynthetic pathway of anthocyanin were significantly higher in the red cells than in the WT cells. Microarray and RT-PCR analyses demonstrated that the TTG1-GL3/TT8-PAP1 complex regulated the biosynthesis of anthocyanins. Furthermore, most of the genes with significant differential expression levels in the red cells versus the WT cells were characterized with diverse biochemical functions, many of which were mapped to different metabolic pathways (e.g., ribosomal protein biosynthesis, photosynthesis, glycolysis, glyoxylate metabolism, and plant secondary metabolisms) or organelles (e.g., chloroplast). We suggest that the difference in gene expression profiles between the two cell lines likely results from cell types, the overexpression of PAP1, and the high metabolic flux toward anthocyanins.

Tick fauna of wild animals received and attended at the Santarém Zoological Park, western Pará State, Brazil

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Kelly Karoline Gomes do Nascimento

2017-08-01

Full Text Available ABSTRACT: Ticks are known worldwide for parasitizing a number of wild hosts. However, few studies have been conducted on ticks in zoos in Brazil. The objective of the present study was to collect, identify, and report the parasitic tick fauna found on wild Amazon animals received and attended at the Santarém Zoological Park from September 2004 to September 2013. In all, 56 animals, including 26 mammals and 30 reptiles, were sampled, from which 1172 ticks were collected and identified, comprising 862 adults, 284 nymphs, and 26 larvae. Nymphs of Amblyomma geayi on three-toed sloth (Bradypus tridactylus, adults of Amblyomma longirostre on black dwarf porcupine (Coendou nycthemera, and nymphs of Amblyomma naponense on southern tamandua (Tamandua tetradactyla were identified for the first time in the country in the present study. Although, the North region is the largest among the five Brazilian regions, this is the first study conducted with ticks and animals attended in a zoo in the Brazilian Amazon.

Cars kill chimpanzees: case report of a wild chimpanzee killed on a road at Bulindi, Uganda.

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McLennan, Matthew R; Asiimwe, Caroline

2016-07-01

Roads have broadly adverse impacts on wildlife, including nonhuman primates. One direct effect is mortality from collisions with vehicles. While highly undesirable, roadkills provide valuable information on the health and condition of endangered species. We present a case report of a wild chimpanzee (Pan troglodytes schweinfurthii) killed crossing a road in Bulindi, Uganda, where chimpanzees inhabit forest fragments amid farmland. Details of the collision are constructed from eyewitness accounts of pedestrians. Physical examination of the cadaver indicated good overall body condition; at 40 kg, the deceased female was heavier than usual for an adult female East African chimpanzee. No external wounds or fractures were noted. Coprological assessment demonstrated infection by several gastrointestinal parasites commonly reported in living wild chimpanzees. Histopathology revealed eosinophilic enteritis and biliary hyperplasia potentially caused by parasite infection. However, eosinophilia was not widely spread into the submucosa, while egg/cyst counts suggested low-intensity parasite infections compared to healthy female chimpanzees of similar age in nearby Budongo Forest. No behavioral indicators of ill health were noted in the deceased female in the month prior to the accident. We conclude that cause of death was acute, i.e., shock from the collision, and was probably unrelated to parasite infection or any other underlying health condition. Notably, this female had asymmetrical polythelia, and, while nursing at the time of her death, had one functioning mammary gland only. In Uganda, where primates often inhabit human-dominated landscapes, human population growth and economic development has given rise to increasing motor traffic, while road development is enabling motorists to travel at greater speeds. Thus, the danger of roads to apes and other wildlife is rising, necessitating urgent strategies to reduce risks. Installation of simple speed-bumps-common on Ugandan

Parasitism and Physiological Trade-Offs in Stressed Capybaras

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Eberhardt, Ayelen T.; Costa, Sebastián A.; Marini, M. Rocío; Racca, Andrea; Baldi, Cecilia J.; Robles, M. Rosario; Moreno, Pablo G.; Beldomenico, Pablo M.

2013-01-01

Parasites play a key role in regulating wildlife population dynamics, but their impact on the host appears to be context-dependent. Evidence indicates that a synergistic interaction between stress, host condition and parasites is implicated in this phenomenon, but more studies are needed to better understand this context-dependency. With the goal to assess the net effect of two types of chronic stress on various host-parasite interactions, we conducted an experiment in capybaras to evaluate the impact of food restriction and physical restraint on the infection intensity of specific gastrointestinal nematodes and coccidia, and how these stressors affected the growth, body condition, and some immuno-physiological parameters. Our hypothesis was that both forms of stress would result in an alteration in the host-parasite interactions, with deteriorated condition and reduced immunological investment leading to high parasite burdens and vice versa. Stressed capybaras had significantly higher coccidia infection intensities; but among individuals that were smaller, those stressed consistently showed lower helminth burdens than controls. Both stress treatments had a marked negative impact on growth and body condition, but concomitantly they had a significant positive effect on some components of the immune system. Our results suggest, on the one hand, that during prolonged periods of stress capybaras preventatively invest in some components of their immunity, such as innate humoural defenses and cells that combat helminths, which could be considered a stress-dependent prophylaxis. On the other hand, stress was found to cause greater infection intensities of protozoans but lower burdens of nematodes, indicating that the relationship between stress, physiological trade-offs and infection depends on the type of parasite in question. Moreover, both findings might be related in a causal way, as one of the immunological parameters enhanced in stressed capybaras is associated with

Parasites

Centers for Disease Control (CDC) Podcasts

2010-05-06

In this podcast, a listener wants to know what to do if he thinks he has a parasite or parasitic disease.  Created: 5/6/2010 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 5/6/2010.

Pulmonary hypertension in wild type mice and animals with genetic deficit in KCa2.3 and KCa3.1 channels.