Rapid sequence modification in the highly polymorphic region (HPR) of the hemagglutinin gene of the infectious salmon anaemia virus (ISAV) suggests intra-segmental template switching recombination     

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   

Increased growth hormone (GH), growth hormone receptor (GHR), and insulin-like growth factor I (IGF-I) gene transcription after hyperosmotic stress in the Brazilian flounder Paralichthys orbignyanus     

Karina M. Meier  Márcio A. Figueiredo  Michel T. Kamimura  Jomar Laurino  Rodrigo Maggioni  Luciano S. Pinto  Odir A. Dellagostin  Marcelo B. Tesser  Luís A. Sampaio  Luis F. Marins 《Fish physiology and biochemistry》2009,35(3):501-509

  相似文献   

Overall development of a bioprocess for the outdoor production of Nannochloropsis gaditana for aquaculture          下载免费PDF全文

Karina Riveros  Claudia Sepulveda  Jazmín Bazaes  Paola Marticorena  Carlos Riquelme  Gabriel Acién 《Aquaculture Research》2018,49(1):165-176

In this paper, a systematic methodology is shown for the scaling‐up of Nannochloropsis gaditana production for aquaculture uses. First, an adequate culture medium was developed, prepared using fertilizers instead of pure chemicals. Subsequently, the performance of N. gaditana was modelled as a function of average irradiance; this model being validated in continuous culture experiments. The model was used to determine the optimal dilution rate as well as the expected biomass concentration and productivity at optimal conditions. Finally, outdoor experiments were performed to confirm the model's validity and to determine optimal conditions at real production step. Biomass productivity values of up to 0.08 g L^?1 day^?1 were obtained at an optimal dilution rate of 0.25 per day in 0.2 m wide flat‐panel reactors using culture medium containing 0.4 g/L NO^?₃ and 0.034 g/L·PO₄^?3. Fish trials with Atlantic Salmon demonstrated that the inclusion of produced biomass into fed increase the final weight up to 5%, thus confirming the adequacy of the biomass produced for aquaculture uses. The growth model and the scaling‐up strategy proposed here are necessary to develop real industrial‐scale processes capable of supplying microalgal biomass to the aquaculture markets, which in turn require a guaranteed supply and quality of the raw materials provided.  相似文献   

The mobility of nitrification inhibitors under simulated ruminant urine deposition and rainfall: a comparison between DCD and DMPP     

Karina A. Marsden  Antonio J. Marín-Martínez  Antonio Vallejo  Paul W. Hill  Davey L. Jones  David R. Chadwick 《Biology and Fertility of Soils》2016,52(4):491-503

  相似文献   

Silicon Effects on Metal Tolerance and Structural Changes in Maize (Zea mays L.) Grown on a Cadmium and Zinc Enriched Soil     

da Cunha  Karina Patrícia Vieira  do Nascimento  Clístenes Williams Araújo 《Water, air, and soil pollution》2009,199(1-4):323-341

Water, Air, & Soil Pollution - The southern sector of the Guadiana River basin (GRB) drains the central-western part of the Iberian Pyrite Belt, an area with many polymetallic sulfide deposits...  相似文献   

Ixodid ticks parasitizing Iberian red deer (Cervus elaphus hispanicus) and European wild boar (Sus scrofa) from Spain: geographical and temporal distribution     

Ruiz-Fons F  Fernández-de-Mera IG  Acevedo P  Höfle U  Vicente J  de la Fuente J  Gortazár C 《Veterinary parasitology》2006,140(1-2):133-142

Commercial hunting of Spanish wild ungulates has made them an important economic resource. Wild ungulates may have an important role in the maintenance of ixodid tick populations, and also as reservoirs of pathogens. We studied the ixodid ticks that parasitize Iberian red deer and European wild boar from Spain. Ixodid ticks (n=6,336) were collected from 431 Iberian red deer and 142 wild boar in different regions of Spain. We found 10 different ixodid tick species parasitizing Iberian red deer, mainly Hyalomma marginatum marginatum (63.7%), Rhipicephalus (Boophilus) annulatus (7.9%) and R. bursa (7.5%). R. (Boophilus) annulatus was only collected in the province of Cádiz (southern Spain). We found 8 ixodid tick species on the wild boar, mainly Hy. m. marginatum (68.7%), R. bursa (14.6%) and Dermacentor marginatus (9.3%). We found one adult Hy. marginatum rufipes and one adult Hy. anatolicum excavatum parasitizing wild boar from south-central Spain. Mean prevalence of ixodid ticks was 41.3+/-0.08% (n=475) and 31+/-0.09% (n=284) and intensity of parasitization was 13.9+/-0.2 (n=283) and 13.6+/-0.3 (n=130) ticks/animal for Iberian red deer and wild boar, respectively. Only 5 of the 13 ixodid tick species found were shared by Iberian red deer and wild boar. This finding could indicate a host preference when Iberian red deer and wild boar share common habitats. In both Iberian red deer and wild boar from south-central Spain the monthly relative frequencies of Hy. m. marginatum and R. bursa presented an inverse pattern. The highest Hy. m. marginatum relative frequencies coincided with the lowest R. bursa relative frequencies along the year. R. bursa and I. ricinus were present in areas from northern to southern Spain while Hyalomma sp. and D. marginatus were exclusively collected in the two southern thirds of Spain. Haemaphysalis sp. and D. reticulatus were collected in northern Spain. Hy. m. marginatum and R. bursa were present during the whole year in red deer and wild boar from south-central Spain, showing more than one life cycle per year. These results are important for understanding the role of wild ungulates in the maintenance of tick infestations and to improve tick control programmes.  相似文献   

Analysis of Quality Protein Changes in Nixtamalized QPM Flours as a Function of the Steeping Time     

I. Rojas‐Molina  E. Gutirrez  M. E. Corts‐Acevedo  A. Falcn  R. Bressani  A. Rojas  C. Ibarra  J. L. Pons‐Hernndez  S. H. Guzmn‐Maldonado  A. Cornejo‐Villegas  M. E. Rodríguez 《Cereal Chemistry》2008,85(3):409-416

This study showed the protein changes in Quality Protein Maize (QPM H‐368C) during the traditional nixtamalization process as a function of the steeping time from 0 to 15 hr. Protein content (N × 6.25), pH, protein fractionation, reactive lysine, essential amino acids, and protein digestibility were analyzed to explain the protein quality modifications in nixtamalized corn flours (NQF). The thermoalkaline process increased significantly (P ≤ 0.05) the protein content (5.57 ± 0.86%) in NQF obtained at 3, 5, 7, 9, 11, 13, and 15 hr of steeping time compared with native corn or corn without treatment (NC). The pH values of NQF were not proportional to the steeping time and significantly different (P ≤ 0.05) between them. At 5 hr critical steeping time, the total lysine and reactive lysine content decreased severely (36 and 32%, respectively) with statistical differences (P ≤ 0.05) compared with NC. On the other hand, the tryptophan content decreased significantly (P ≤ 0.05) at steeping times of 5–15 hr (38.70 ± 6.7%) compared with NC. The changes in the lysine and tryptophan content were not proportional to the steeping time. The protein recovery in the albumin and globulin fraction diminished (P ≤ 0.05) with respect to raw corn. The protein recovery for γ‐zeins, glutelin‐like proteins, glutelins, and residue increased. A significant (P ≤ 0.05) decrease was found in the essential amino acids in NQF with 3–7 hr of steeping time compared with NC. Equally important was the reduction in protein digestibility observed in NQF steeped at long steeping times (11–15 hr) with significant (P ≤ 0.05) differences compared with NC. The protein solubility distribution along the steeping step and the essential amino acids location, specifically lysine in corn kernel, could explain partially the protein quality changes observed in this research. Finally, these results contribute to reconciling discrepancies associated with the protein quality modifications in nixtamalized corn reported previously in literature.  相似文献   

Notes on Propagation of Butterfly Peacock Bass Cichla ocellaris (Bloch & Schneider, 1801) in a Tropical Fish Hatchery          下载免费PDF全文

J Wesley Neal  Karina M Olivieri‐Velázquez 《Aquaculture Research》2015,46(7):1785-1787

  相似文献   

Evaluation of a decision support strategy for the control of powdery mildew,Erysiphe necator (Schw.) Burr., in grapevine in the central region of Chile          下载免费PDF全文

Héctor Valdés‐Gómez  Miguel Araya‐Alman  Carolina Pañitrur‐De la Fuente  Nicolás Verdugo‐Vásquez  Mauricio Lolas  César Acevedo‐Opazo  Christian Gary  Agnès Calonnec 《Pest management science》2017,73(9):1813-1821

  相似文献   

Experimental evaluation of four airway devices in anaesthetized New Zealand White rabbits     

Sandra Wenger  Désirée Müllhaupt  Stefanie Ohlerth  Sarah Prasse  Karina Klein  Bianca da Silva Valente  Martina Mosing 《Veterinary anaesthesia and analgesia》2017,44(3):529-537

Objective

To compare airway management during induction of anaesthesia, spontaneous ventilation (SV) and controlled mechanical ventilation (CMV), using an endotracheal tube (ETT), laryngeal mask (LM), rabbit-specific supraglottic airway device (v-gel) or facemask (FM).

Study design

Prospective randomized crossover experiment.

Animals

Ten New Zealand White rabbits.

Methods

After premedication, rabbits were randomly allocated to four groups: 1) ETT; 2) LM; 3) v-gel or 4) FM. The required dose of propofol, duration and number of attempts to place an airway device and leakage during SV and CMV at different peak inspiratory pressures (6, 10, 12, 14 and 16 cmH₂O) were recorded. Computed tomography (CT) of the head, neck and abdomen were performed before and after CMV.

Results

Significantly less propofol and time [2.0 ± 0.5 mg kg^?1, 82 ± 34 seconds, p < 0.001] were needed to place the FM compared to the three other groups [v-gel 5.1 ± 2.1 mg kg^?1, 302 ± 124 seconds; LM 4.8 ± 1.2 mg kg^?1, 275 ± 89 seconds; ETT 5.5 ± 1.4 mg kg^?1, 315 ± 147 seconds]. A leak > 25% of the tidal volume occurred at the lowest pressure in FM [median (range), 6 (6–8) cmH₂O], which was significantly lower than with v-gel [16 (6–no leak at 16) cmH₂O], LM [>16 (6–no leak at 16)] or ETT [>16 (no leak at 16) cmH₂O] (p < 0.001). On CT images, the height and width of the larynx were significantly smaller with v-gel in comparison to FM and LM (p = 0.004). A significant increase in the amount of gas in the stomach (p = 0.007), but not gastric volume, was detected in FM and LM.

Conclusions and clinical relevance

The v-gel is a practical alternative to LM and ETT for airway management and CMV, but can compress the larynx. The FM is easily placed, but significant leakage occurs during CMV.  相似文献