خيارات البحث
النتائج 181 - 190 من 662
Evaluation of direct metagenomics and target enriched approaches for high-throughput sequencing of field rabies viruses
2019
Orłowska, Anna | Iwan, Ewelina | Smreczak, Marcin | Rola, Jerzy
High-throughput sequencing (HTS) identifies random viral fragments in environmental samples metagenomically. High reliability gains it broad application in virus evolution, host-virus interaction, and pathogenicity studies. Deep sequencing of field samples with content of host genetic material and bacteria often produces insufficient data for metagenomics and must be preceded by target enrichment. The main goal of the study was the evaluation of HTS for complete genome sequencing of field-case rabies viruses (RABVs). The material was 23 RABVs isolated mainly from red foxes and one European bat lyssavirus-1 isolate propagated in neuroblastoma cells. Three methods of RNA isolation were tested for the direct metagenomics and RABV-enriched approaches. Deep sequencing was performed with a MiSeq sequencer (Illumina) and reagent v3 kit. Bioinformatics data were evaluated by Kraken and Centrifuge software and de novo assembly was done with metaSPAdes. Testing RNA extraction procedures revealed the deep sequencing scope superiority of the combined TRIzol/column method. This HTS methodology made it possible to obtain complete genomes of all the RABV isolates collected in the field. Significantly greater rates of RABV genome coverages (over 5,900) were obtained with RABV enrichment. Direct metagenomic studies sequenced the full length of 6 out of 16 RABV isolates with a medium coverage between 1 and 71. Direct metagenomics gives the most realistic illustration of the field sample microbiome, but with low coverage. For deep characterisation of viruses, e.g. for spatial and temporal phylogeography during outbreaks, target enrichment is recommended as it covers sequences much more completely.
اظهر المزيد [+] اقل [-]ARTs in wild felid conservation programmes in Poland and in the world
2019
Kochan, Joanna | Niżański, Wojciech | Moreira, Nei | Cubas, Zalmir Silvino | Nowak, Agnieszka | Prochowska, Sylwia | Partyka, Agnieszka | Młodawska, Wiesława | Skotnicki, Józef
With the exception of the domestic cat, all felid species (Felidae) are currently threatened with extinction in their natural habitat. To develop effective and optimal wild cat conservation programmes with assisted reproductive technology (ART) it is necessary to combine advances from different disciplines of science, starting from the biology of the species, through research into the population and habitat, assisted reproductive technologies, establishment of gene banks, developing bioinformatic systems, and ending with biodiversity and endangered species management. In the last few years knowledge of felid reproduction has expanded considerably thanks to comparative studies utilising the domestic cat as a research model for endangered wild cats. Basic reproductive techniques utilised in both domestic cat breeding and rescuing wild felid populations that are threatened with extinction include semen collection and cryopreservation, artificial insemination, oocyte collection, in vitro maturation, in vitro fertilisation, somatic cloning, and embryo transfer. The main directions in which assisted reproductive technologies are being developed in wild cat conservation implementations and the contribution of Polish research centres in advancing these methods are presented.
اظهر المزيد [+] اقل [-]ARTs in wild felid conservation programmes in Poland and in the world
2019
Kochan Joanna | Niżański Wojciech | Moreira Nei | Cubas Zalmir Silvino | Nowak Agnieszka | Prochowska Sylwia | Partyka Agnieszka | Młodawska Wiesława | Skotnicki Józef
With the exception of the domestic cat, all felid species (Felidae) are currently threatened with extinction in their natural habitat. To develop effective and optimal wild cat conservation programmes with assisted reproductive technology (ART) it is necessary to combine advances from different disciplines of science, starting from the biology of the species, through research into the population and habitat, assisted reproductive technologies, establishment of gene banks, developing bioinformatic systems, and ending with biodiversity and endangered species management. In the last few years knowledge of felid reproduction has expanded considerably thanks to comparative studies utilising the domestic cat as a research model for endangered wild cats. Basic reproductive techniques utilised in both domestic cat breeding and rescuing wild felid populations that are threatened with extinction include semen collection and cryopreservation, artificial insemination, oocyte collection, in vitro maturation, in vitro fertilisation, somatic cloning, and embryo transfer. The main directions in which assisted reproductive technologies are being developed in wild cat conservation implementations and the contribution of Polish research centres in advancing these methods are presented.
اظهر المزيد [+] اقل [-]Effects of tiletamine-xylazine-tramadol combination and its specific antagonist on AMPK in the brain of rats
2019
Ma Ning | Li Xin | Wang Hong-bin | Gao Li | Xiao Jian-hua
Introduction: Tiletamine-xylazine-tramadol (XFM) has few side effects and can provide good sedation and analgesia. Adenosine 5’-monophosphate-activated protein kinase (AMPK) can attenuate trigeminal neuralgia. The study aimed to investigate the effects of XFM and its specific antagonist on AMPK in different regions of the brain. Material and Methods: A model of XFM in the rat was established. A total of 72 Sprague Dawley (SD) rats were randomly divided into three equally sized groups: XFM anaesthesia (M group), antagonist (W group), and XFM with antagonist interactive groups (MW group). Eighteen SD rats were in the control group and were injected intraperitoneally with saline (C group). The rats were sacrificed and the cerebral cortex, cerebellum, hippocampus, thalamus, and brain stem were immediately separated, in order to detect AMPKα mRNA expression by quantitative PCR. Results: XFM was able to increase the mRNA expression of AMPKα1 and AMPKα2 in all brain regions, and the antagonist caused the opposite effect, although the effects of XFM could not be completely reversed in some areas. Conclusion: XFM can influence the expression of AMPK in the central nervous system of the rat, which can provide a reference for the future development of anaesthetics for animals.
اظهر المزيد [+] اقل [-]Carbapenem-resistant Pseudomonas aeruginosa originating from farm animals and people in Egypt
2019
Elshafiee Esraa A. | Nader Sara M. | Dorgham Sohad M. | Hamza Dalia A.
Carbapenem-resistant Pseudomonas aeruginosa (CRPA) has become the leading cause of health care-associated infections. Treatment is difficult due to the lack of an effective antimicrobial therapy, and mortality is high. This study investigated the occurrence of CRPA in farm animals (buffaloes and cattle), livestock drinking water, and humans in Egypt.
اظهر المزيد [+] اقل [-]Bivagina pagrosomi Murray (1931) (Monogenea: Polyopisthocotylea), a microcotylid infecting the gills of the gilt-head sea bream Sparus aurata (Sparidae) from the Red Sea: morphology and phylogeny
2019
Dajem Saad Bin | Morsy Kareem | Shati Ali | Ezzat Ahmed | El-Said Fahmy | Abdel-Gaber Rewaida
Monogenea is a class of ectoparasitic flatworms on the skin, gills, or fins of fish. Microcotylidae is a family of polyopisthocotylean monogeneans parasitising only marine fishes. This work describes and taxonomically determines a microcotylid polyopisthocotylean monogenean in an important fish in Saudi aquaculture.
اظهر المزيد [+] اقل [-]Anti-CyHV-3 effect of fluorescent, tricyclic derivative of acyclovir 6-(4-MeOPh)-TACV in vitro
2019
Troszok Agnieszka | Kolek Ludmiła | Szczygieł Joanna | Ostrowski Tomasz | Adamek Mikołaj | Irnazarow Ilgiz
Cyprinid herpesvirus 3 (CyHV-3) is a virus infecting carp with disease symptoms of gill necrosis, fish discoloration, sunken eyes, and mortality reaching 90%. Several research groups have examined how to potentially abate the consequences of viral activity. Recently we showed that acyclovir inhibits CyHV-3 replication in vitro and in the present study we examined the anti-CyHV-3 activity of the tricyclic derivative of acyclovir 6-(4-MeOPh)-TACV (T-ACV), a fluorescent molecule known for higher lipophilicity than acyclovir, and therefore potentially better candidate for application in vivo.
اظهر المزيد [+] اقل [-]Taxonomic justification of the pathogenic strongylid infecting the Arabian camel Camelus dromedarius as Haemonchus longistipes by morphological and molecular phylogeny
2019
Dajem Saad | Morsy Kareem | Al-Kahtani Mohammed | Abdel-Gaber Rewaida
Introduction: There is still lack of morphological and phylogenetic information on the pathogenic nematode of the camel Haemonchus longistipes. In the present study, this parasite was isolated in Saudi Arabia and described.
اظهر المزيد [+] اقل [-]Relationship between mRNA of immune factors expressed by milk somatic cells and bacteria present in healthy lactating Holstein cows
2019
Ohtsuka Hiromichi | Hirose Honami | Murakami Kenji | Murata Ryo | Kato Toshihide | Tajima Motoshi
The characteristics of immune factors in somatic cells from lactating dairy cows and their association with commensal bacteria in normal milk have not been clarified. This study investigated the relationship between the pathogenic bacteria in milk and somatic cell immune factors in healthy lactating cows.
اظهر المزيد [+] اقل [-]African swine fever virus – persistence in different environmental conditions and the possibility of its indirect transmission
2019
Mazur-Panasiuk Natalia | Żmudzki Jacek | Woźniakowski Grzegorz
Since 2007, African swine fever (ASF) has posed a serious threat to the European swine industry. In Poland, the numbers of reported outbreaks in pigs and affected areas grow every year. In 2018, the disease was noted in Western Europe, in Belgium specifically, where several hundred infected wild boars have been detected so far. In 2018, the virus unexpectedly emerged in pig holdings in eastern China, northern Mongolia, Vietnam, and Cambodia, causing worldwide concern about its further spread. Since there is still no vaccine available, the only approach to control the disease is biosecurity. Identification of potential sources of the virus is extremely important in light of its phenomenal survivability. The review summarises the current knowledge about ASFV survivability and resistance to environmental conditions, and discusses the role of indirect contact in spreading the disease.
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