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11.
12.
Radzi R Osaki T Tsuka T Imagawa T Minami S Nakayama Y Okamoto Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(5):545-551
We examined the effects of photodynamic hyperthemal therapy (PHT), which is a combination of photodynamic therapy (PDT) and hyperthermia (HT), on the apoptosis and cell cycle progression of murine melanoma B16F10 cells. The percentage of apoptotic cell was determined by flow cytometry using fluorescein isothiocyanate (FITC)-conjugated Annexin V and propidium iodide (PI) double staining. The cell cycle analysis was performed by PI staining with flow cytometry. The expression of cyclins and heat shock protein 70 (Hsp70) were examined by a Western blotting analysis. PHT induces death in B16F10 cells, and PHT-mediated apoptosis occurred acutely and persistently in vitro. Our study demonstrated that PHT using indocyanine green (ICG) and near infrared (NIR) light source induces apoptosis and G0/G1 cell cycle arrest in the B16F10 cells. 相似文献
13.
Ballent M Lifschitz A Virkel G Sallovitz J Maté L Lanusse C 《Veterinary journal (London, England : 1997)》2012,192(3):422-427
The impact of an efflux pump-related interaction between ivermectin and danofloxacin on their intestinal transport (ex vivo) and disposition kinetics (in vivo) was assessed. Eighteen male Corriedale sheep were randomly assigned to one of three groups. Animals in Group A received 0.2mg/kg ivermectin by SC injection, those in Group B were given 6 mg/kg danofloxacin SC on two occasions 48 h apart and those in Group C were treated with both compounds at the same rates. Plasma concentrations of ivermectin and danofloxacin were measured by HPLC using fluorescence detection. Ex vivo intestinal drug transport activity was measured by the use of the Ussing chamber technique. Plasma concentrations of ivermectin in the first 6 days after injection tended to be higher in Group C than Group A. Contemporaneous treatment with ivermectin significantly increased systemic exposure to danofloxacin (AUC values were 32-35% higher) and prolonged the elimination half-life of danofloxacin (40-52% longer). Ex vivo, incubation with ivermectin significantly decreased the efflux transport of rhodamine 123, a P-glycoprotein substrate, in sheep intestine, but no significant effect of danofloxacin on transport activity was observed. Evaluation of the interaction of danofloxacin with the breast cancer resistance protein (BCRP) showed that pantoprazole and ivermectin significantly decreased danofloxacin secretion in the rat intestine. Thus, the ivermectin-induced reduction of danofloxacin efflux transport observed in this study may involve BCRP activity but the involvement of P-glycoprotein cannot be ruled out. 相似文献
14.
M. Ballent M. R. Wilkens L. Maté A. S. Muscher G. Virkel J. Sallovitz B. Schröder C. Lanusse A. Lifschitz 《Journal of veterinary pharmacology and therapeutics》2013,36(6):576-582
The role of the transporter P‐glycoprotein (P‐gp) in the disposition kinetics of different drugs therapeutically used in veterinary medicine has been demonstrated. Considering the anatomo‐physiological features of the ruminant species, the constitutive expression of P‐gp (ABCB1) along the sheep gastrointestinal tract was studied. Additionally, the effect of repeated dexamethasone (DEX) administrations on the ABCB1 gene expression in the liver and small intestine was also assessed. The ABCB1 mRNA expression was determined by real‐time quantitative PCR. P‐gp activity was evaluated in diffusion chambers to determine the efflux of rhodamine 123 (Rho 123) in the ileum from experimental sheep. The constitutive ABCB1 expression was 65‐fold higher in the liver than in the intestine (ileum). The highest ABCB1 mRNA expression along the small intestine was observed in the ileum (between 6‐ and 120‐fold higher). The treatment with DEX did not elicit a significant effect on the P‐gp gene expression levels in any of the investigated gastrointestinal tissues. Consistently, no significant differences were observed in the intestinal secretion of Rho 123, between untreated control (Peff S‐M = 3.99 × 10?6 ± 2.07 × 10?6) and DEX‐treated animals (Peff S‐M = 6.00 × 10?6 ± 2.5 × 10?6). The understanding of the efflux transporters expression and activity along the digestive tract may help to elucidate clinical implications emerging from drug interactions in livestock. 相似文献
15.
Abd Rahman Muhammad Radzi Ahmad Harlina Fadhullah Widad 《Paddy and Water Environment》2019,17(4):571-579
Paddy and Water Environment - The application of isoprothiolane in rice cultivation may give a risk to the aquatic ecosystem. The present study was undertaken to determine the level of... 相似文献
16.
Stable isotopes and gut contents indicate differential resource use by coexisting asp (Leuciscus aspius) and pikeperch (Sander lucioperca)
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Mojmír Vašek Antti P. Eloranta Ivana Vejříková Petr Blabolil Milan Říha Tomáš Jůza Marek Šmejkal Josef Matěna Jan Kubečka Jiří Peterka 《Ecology of Freshwater Fish》2018,27(4):1054-1065
Differential use of habitat and prey resources is an important mechanism that may allow coexistence of sympatric species. Unlike interactions between smaller cyprinid and percid fishes, the resource use by coexisting predatory asp (Leuciscus aspius) and pikeperch (Sander lucioperca) is relatively unknown. Here, gut content and stable isotope analyses were used to study ontogenetic dietary shifts and interspecific trophic niche overlap between asp and pikeperch coexisting in two reservoirs. The hypothesis that both species show an ontogenetic dietary shift from small invertebrates to large fish prey, but at the same time use different prey resources to reduce potential competitive interactions, was validated. The isotopic niches of the two predators showed no, or only a moderate, degree of overlap (0%–65%). The ontogenetic changes in the degree of interspecific isotopic niche overlap were different in the two reservoirs, suggesting that trophic segregation can be dynamic and variable among systems. Gut contents revealed that small (<100 mm standard length) asp consumed mostly terrestrial invertebrates and emerged aquatic insects, whereas small pikeperch foraged on zooplankton, larval and pupal stages of aquatic insects and fish. Larger individuals (>100 mm) of both species were predominantly piscivorous, with asp consuming more cyprinid prey and pikeperch more percid prey. Coexisting asp and pikeperch populations are able to utilise different prey resources, thereby reducing potential negative competitive interactions. 相似文献
17.
Context
Although small isolated habitat patches may not be able to maintain a minimum viable population, small patches that are structurally isolated may be functionally connected if individuals can cross the gaps between them, in which case, their areas could be added to form a larger habitat patch, eventually surpassing the size threshold for holding a viable population.Objectives
We studied whether models based on the size and isolation of habitat patches could be used to predict the distribution of the Chestnut-throated Huet-Huet (Pteroptochos castaneus) in fragmented landscapes of the coastal range of the Maule region, central Chile.Methods
We selected seven 10,000-ha landscapes (8.4–70.7% forest cover). For each habitat patch we made 18 predictions of the presence of the species based on the combination of two thresholds: three critical patch sizes for maintaining a viable population (62.5, 125 and 250 ha) and six critical isolation distances between patches (0, 10, 50, 100, 150 and 200 m). We used playbacks in 59 sampling points to estimate the species’ presence/absence. We used logistic regressions to test whether the output of the patch-matrix models could explain part of the variation in the presence of Pteroptochos castaneus.Results
The best predictions for the presence of P. castaneus were obtained with the most conservative scenarios (125–250 ha to 0–10 m), including a positive effect of the understory cover and a lack of effect of the forest type (native or exotic).Conclusions
Our findings suggest that the long term persistence of P. castaneus may depend on the existence of large and/or very connected forest tracts.18.
A new family of cereal tandem repeats was isolated, characterised and designated as spelt-1. The family of repeats comprises
about 2% of the Aegilops speltoides genome; however, its content differs considerably in the genomes of various Triticeae
species. Copy number of the constituent sequence, relative to Ae. speltoides, proved to be 40-60 times reduced in the genomes
of tetraploid wheats, 400-fold reduced in the genome of Triticum monococcum, and 1200-2400 times in the genomes of the other
19 Triticeae species studied. Drastic difference in the copy number and homology extent of the spelt-1 family sequences between
Ae. speltoides and other diploid species allows the utilisation of these sequences as species-specific telomeric markers for
Ae. speltoides, provided stringent hybridisation conditions apply. RFLP (restriction fragment length polymorphisms) analysis
of spelt-1 reveals polymorphism between the above species. This study of spelt-1 organisation in different Triticum species
provided further substantiation of the polyphyletic origin of the B genome of polyploid wheat.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
19.
Muhammad M. Mackeen Abdul M. Ali Mohd A. Abdullah Rozita M. Nasir Nashriyah B. Mat Abdul R. Razak Kazuyoshi Kawazu 《Pest management science》1997,51(2):165-170
Methanolic extracts of 79 Malaysian plants representing 42 families were assessed for antinematodal activity against Bursaphelenchus xylophilus using a fungal-feeding assay. Extracts of 27 plants from 19 families showed antinematodal activity, while 52 species were inactive. Five extracts (Sauropus androgynus, Eugenia polyantha, Areca catechu, Piper betle and Piper nigrum) exhibited very strong activity against Bursaphelenchus xylophilus at a minimum effective dose (MED) of 0·625 mg per ball. Strong antinematodal activity (MED: 1·25–2·5 mg per ball) was shown by the extracts of Spondias cyntherea, Codiageum variegatum, Euodia glabra and Cicca acida. Eleven extracts (Carica papaya, Ipomoea aquatica, Ocimum basilicum, Leea gigantea, Pithecellobium jiringa, Crypteronia paniculata, Myristica fragrans, Murraya koenigii, Leucaena leucocephala, Melastoma malabathricum and Morinda citrifolia) demonstrated moderate activity between MED of 5 and 10 mg per ball, and weak activity was observed in seven extracts (Ipomoea batatas, Cymbopogon citratus, Garcinia atroviridis, Psophocarpus tetragonolobus, Tamarindus indica, Allium odorum and Stenochalaena palustris). © 1997 SCI 相似文献
20.
Matías Cárdenas Claudia Galleguillos Karina Acevedo Catarina Ananias Javiera Alarcón Sofía Michelson Jorge Toledo Margarita Montoya Claudio Meneses Eduardo Castro-Nallar Yesseny Vásquez-Martínez Marcelo Cortez-San Martin 《Journal of fish diseases》2020,43(12):1483-1496
The ISAV has a genome composed of eight segments of (–)ssRNA, segment 6 codes for the hemagglutinin–esterase protein, and has the most variable region of the genome, the highly polymorphic region (HPR), which is unique among orthomyxoviruses. The HPR has been associated with virulence, infectivity and pathogenicity. The full length of the HPR is called HPR0 and the strain with this HPR is avirulent, in contrast to strains with deleted HPR that are virulent to varying degrees. The molecular mechanism that gives rise to the different HPRs remains unclear. Here, we studied in vitro the evolution of reassortant recombinant ISAV (rISAV) in Atlantic salmon head kidney (ASK) cells. To this end, we rescued and cultivated a set of rISAV with different segment 6-HPR genotypes using a reverse genetics system and then sequencing HPR regions of the viruses. Our results show rapid multiple recombination events in ISAV, with sequence insertions and deletions in the HPR, indicating a dynamic process. Inserted sequences can be found in four segments of the ISAV genome (segments 1, 5, 6, and 8). The results suggest intra-segmental heterologous recombination, probably by class I and class II template switching, similar to the proposed segment 5 recombination mechanism. 相似文献