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Identification of DNA sequence responsible for 5-bromodeoxyuridine-induced gene amplification 总被引：1，自引：0，他引：1
Bromodeoxyuridine (BrdUrd) treatment of the prolactin nonproducing subclone of GH cells (rat pituitary tumor cells) induces amplification of a 20-kilobase DNA fragment including all of the prolactin gene coding sequences. This amplified DNA segment, which is flanked by two unamplified regions, thus designates a unit of BrdUrd-induced amplified sequence. Cloned DNA segments, 10.3 kilobases long, from the 5' end of the rat prolactin gene of BrdUrd-responsive and -nonresponsive cells, were ligated to the thymidine kinase gene of herpes simplex virus type 1 (HSV1TK), and the hybrid DNA was transferred to thymidine kinase-deficient mouse fibroblast cells by transfection. The HSV1TK gene and the rat prolactin gene were amplified together in drug-treated transfectants carrying the hybrid DNA HSV1TK gene and rat prolactin gene of BrdUrd-responsive GH cells. These results suggest that the 10.3-kilobase DNA segment at the 5' end of the rat prolactin gene of BrdUrd-responsive GH cells carries the information for drug-induced gene amplification (amplicon) and that another gene, such as the HSV1TK gene, is also amplified when the latter is placed adjacent to this segment. 相似文献
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Sjöblom T Jones S Wood LD Parsons DW Lin J Barber TD Mandelker D Leary RJ Ptak J Silliman N Szabo S Buckhaults P Farrell C Meeh P Markowitz SD Willis J Dawson D Willson JK Gazdar AF Hartigan J Wu L Liu C Parmigiani G Park BH Bachman KE Papadopoulos N Vogelstein B Kinzler KW Velculescu VE 《Science (New York, N.Y.)》2006,314(5797):268-274
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King JS McAllan B Spielman DS Lindsay SA Hůrková-Hofmannová L Hartigan A Al-Qassab SE Ellis JT Slapeta J 《Veterinary research》2011,42(1):75
ABSTRACT: Experimental infections of Sminthopsis crassicaudata, the fat-tailed dunnart, a carnivorous marsupial widely distributed throughout the arid and semi-arid zones of Australia, show that this species can act as an intermediate host for Neospora caninum. In contrast to existing models that develop relatively few N. caninum tissue cysts, dunnarts offer a new animal model in which active neosporosis is dominated by tissue cyst production. The results provide evidence for a sylvatic life cycle of N. caninum in Australia between marsupials and wild dogs. It establishes the foundation for an investigation of the impact and costs of neosporosis to wildlife. 相似文献
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Bing Y. Zhu Ashlie Hartigan George Reppas Damien P. Higgins Paul J. Canfield Jan Šlapeta 《Veterinary parasitology》2009
Two yellow-bellied gliders (Petaurus australis) had an intraerythrocytic parasite closely related to the cyst-forming coccidia (Apicomplexa: Sarcocystidae). The parasitaemia persisted for 3 months or more but was observed to clear within 3 years in captivity. The parasite appears not to significantly debilitate its infected host. Traditionally, using morphological identification, the intraerythrocytic parasite would have been classified within the Hepatozoon species typically found in red blood cells. However, molecular diagnostic techniques targeting the parasite's SSU rDNA and LSU rDNA demonstrated the unusual identity of this blood parasite and disputed its identity as a haemogregarine parasite of the genus Hepatozoon. The sequence was compared with available sequences from diverse mammalian and non-mammalian blood parasites (malaria, piroplasms, hemosporidia and sarcosporidia). The intraerythrocytic blood parasite was found to be most closely related to the cyst-forming coccidia including Besnoitia spp., Cystoisospora spp., Hammondia spp., Hyaloklossia lieberkuehni, Neospora caninum, Sarcocystis spp. and Toxoplasma gondii. The life cycle of this intraerythrocytic parasite remains unknown. The presented DNA identification demonstrates its suitability for an improved identification of blood parasites. 相似文献
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P. J. Hartigan 《Veterinary research communications》1977,1(1):307-321
The role of non-specific bacteria in the infertility of clinically normal repeat-breeder cows is reviewed, and data are presented from a recent study in which bacteriological and histological samples were taken from the uteri of dairy cows at intervals during the non-gravid period. The evidence does not support the view that endometritis is an important cause of this infertility. In the absence of accurate counts of the bacteria present in the uterus at the time of service and during the subsequent oestrous cycle, it is impossible to determine whether pathogenic bacteria cause the infertility by injuring the gametes or the developing conceptus. A comprehensive quantitative study is needed of the microbiology of the uterus of the repeatbreeder cow at service and during the subsequent oestrous cycle.
Kurzfassung Die Literatur über die Wirkung nichtspezifischer Bakterien auf die Infertilität von klinisch normalen Zuchtkühen wird überarbeitet; da bei werden den Daten aus einer kürzlich durchgeführten Studie, bei der den Uteri von Milchkühen während des gesamten Zeitraums der Nichtträchtigkeit wiederholt Bakterien und Gewebeproben entnommen worden waren, besondere Bedeutung beigemessen. Es konnte kein Beweis für die Annahme erbracht werden, dass Endometritis ein wesen liche Ursache für Unfruchtbarkeit ist. Ohne eine quantitative Untersuchung der Bakterien, die sich während der Deckzeit und dem anschliessendin Brunstzyklus im Uterus befinden, lässt sich nicht feststellen, ob pathogene Bakterien insofern Unfruchtbarkeit verursachen, als sie die Gameten des wachsenden Embryos zerstören oder verletzen. Das vorliegende, nichtquantitative Datenmaterial lässt diesen Schluss nicht zu. Eine umfassende quantitative Untersuchung der Uterusmikrobiologie der Zuchtkuh während der Deckzeit und des folgenden Brunstzyklus ist dringend erforderlich.
Resume La littérature traitant du rôle des bactéries non spécifiques dans la stérilité de vaches de reproduction multiple cliniquement normales est passée en revue compte tenu notamment des données tirées d'une récente étude au cours de laquelle des échantillons bactériologiques et histologiques ont été prélevés a plusieurs reprises dans l'utérus de vaches laitières durant la période de non-gestation. L'expérience ne nonfirme pas l'opinion selon laquelle l'endométrite est une cause importante de stérilité. En l'absence de données quantitatives sur les bactéries présentes dans l'utérus au moment de la saillie ou durant le cycle oestral ultérieur, il est impossible de déterminer si des bactéries pathogènes provoquent ou non la stérilité en détruisant ou en endommangeant les gamètes ou le produit de la conception en développment. D'après les données non quantitatives disponibles, il ne semble pas qu'il en soit ainsi. Il est nécessaire de mener une étude quantitative complète de la microbiologie de l'utérus de la vache de reproduction multiple au moment de la saillie et pendant le cycle oestral consecutif.
Riassunto Gli autori esaminano la letteratura riguardante il ruolo dei batteri aspecifici nella sterilità delle fattrici multipare clinicamente normali, in particolare alla luce dei dati forniti da un recente studio durante il quale sono stati effettuati ripetuti prelievi istologici e batteriologici dell'utero di bovine de latte al di fuori del periodo di gravidanza.I risultati non sono in favore del punto di vista secondo il quale l'endometrite sarebbe una seria causa di sterilità. In assenza di un conteggio quantitativo dei batteri presenti nell' utero al momento della monta o durante il successivo ciclo estrale, è impossibile stabilire se i batteri patogeni sono causa di sterilità distruggendo o danneggiando i gameti o il feto. I dati disponobili, non quantitativi, non corroborano questa tesi. Si segnala la necessità di un esauriente studio quantitativo della microbiologia dell' utero della bovina multipara al momento della monta e durante il successivo ciclo estrale.相似文献
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Beth Okamura Ashlie Hartigan Paul F. Long Paolo Ruggeri Katie Smith-Easter Jason D. Schooley 《Journal of fish diseases》2020,43(9):979-989
Polypodium hydriforme is a parasitic cnidarian that develops within the eggs of acipenseriform fish in the Old and New Worlds. Currently regarded as monotypic, P. hydriforme has been studied largely in the context of caviar production in Russian sturgeon species. We report the first robust epidemiological study of P. hydriforme in North American acipenseriform fish. We sampled infection prevalences (in 2017 and 2018) and intensities (in 2017) during annual surveys of American Paddlefish, Polyodon spathula, caught during spawning migration in north-eastern Oklahoma. Egg masses were characterized for the presence and intensity of P. hydriforme infection. Prevalences were similar in 2017 and 2018 (49% and 45%, respectively). Generally, a small number of eggs were infected per egg mass, but a few were heavily infected. Longer, heavier and older fish are more likely to be infected and to harbour more severe infections. In addition, infection is linked to decreases in roe fat weight independently of fish length, weight, age or roe weight. Infection thus diminishes Paddlefish energy reserves (roe fat) which could in turn impact host fitness. Our results raise questions about the impacts of infection on caviar production and Paddlefish conservation and suggest insights on infection dynamics and parasite strategies. 相似文献