677 research outputs found
Coordinated regulation of chromatophore differentiation and melanogenesis during the ontogeny of skin pigmentation of Solea senegalensis (Kaup, 1858)
Abnormal pigmentation of Senegalese sole has been described as one problem facing the full exploitation of its commercial production. To improve our understanding of flatfish pigmentation of this commercially important species we have evaluated eleven genes related to two different processes of pigmentation: melanophore differentiation, and melanin production. The temporal distribution of gene expression peaks corresponds well with changes in pigmentation patterns and the intensity of skin melanization. Several gene ratios were also examined to put in perspective possible genetic markers for the different stages of normal pigmentation development. Further, the phenotypic changes that occur during morphogenesis correspond well with the main transitions in gene expression that occur. Given the dramatic phenotypic alterations which flatfish undergo, including the asymmetric coloration that occurs between the ocular and the blind side, and the synchrony of the two processes of morphogenesis and pigmentation ontogenesis, these species constitute an interesting model for the study of pigmentation. In this study we present a first approximation towards explaining the genetic mechanisms for regulating pigmentation ontogeny in Senegalese sole, Solea senegalensis.Ministry of Science and Innovation (MICIIN) of the Spanish Government [AGL2008-03897-C04-01/ACU]; European Community [FP7/2007-2013-222719-LIFECYCLE]; Spanish Governmentinfo:eu-repo/semantics/publishedVersio
Thermal imprinting modifies adult stress and innate immune responsiveness in the teleost sea bream
The impact of thermal imprinting on the plasticity of the hypothalamic-pituitary-interrenal (HPI) axis and stress response in an adult ectotherm, the gilthead sea bream (Sparus aurata, L.), during its development was assessed. Fish were reared under 4 thermal regimes, and the resulting adults exposed to acute confinement stress and plasma cortisol levels and genes of the HPI axis were monitored. Changes in immune function, a common result of stress, were also evaluated using histomorphometric measurements of melanomacrophages centers (MMCs) in the head kidney and by monitoring macrophage-related transcripts. Thermal history significantly modified the HPI responsiveness in adult sea bream when eggs and larvae were reared at a higher than optimal temperature (HT, 22 degrees C), and they had a reduced amplitude in their cortisol response and significantly upregulated pituitary pomc and head kidney star transcripts. Additionally, after an acute stress challenge, immune function was modified and the head kidney of adult fish reared during development at high temperatures (HT and LHT, 18-22 degrees C) had a decreased number of MMCs and a significant downregulation of dopachrome tautomerase. Thermal imprinting during development influenced adult sea bream physiology and increased plasma levels of glucose and sodium even in the absence of an acute stress in fish reared under a high-low thermal regime (HLT, 22-18 degrees C). Overall, the results demonstrate that temperature during early development influences the adult HPI axis and immune function in a teleost fish.project Lifecycle EU-FP7 [222719]FCT- Foundation for Science and Technology [CCMAR/Multi/04326/2013]info:eu-repo/semantics/publishedVersio
Role of Positive and Negative Urgency and Social Context on Problematic Alcohol Use Behaviors
poster abstractSocial context influences drinking behaviors; in particular, problematic alcohol use among adolescents and young adults is more frequent in those who drink in more social contexts or who drink for social reasons. Moreover, although positive and negative urgency (i.e., the tendency to act rashly in response to extreme positive or negative emotional states, respectively) also relate to problematic alcohol use, it is unclear whether these impulsivity traits affect problematic alcohol use through social context. As such, the current study examined how positive and negative urgency influence problematic alcohol consumption through the social context of drinking. Participants (n = 348, n = 70 men; Mean age = 20 (SD= 4.5); 78.2% Caucasian) were recruited from the Introduction to Psychology course from IUPUI and received course credit for the completion of an online survey. A series of correlation and mediation analyses were conducted. Problematic alcohol use was significantly related to positive urgency (r=0.33, p<.001) and negative urgency (r= 0.29, p<.001). Although contextual drinking factors did not mediate the relationship between urgency and problematic alcohol use, the relationship between urgency and problematic alcohol use was significantly mediated by the endorsement of social drinking motives (e.g., I drink in order to be more social) (indirect effect of positive urgency b = 1.85, indirect effect of negative urgency b =2.02). Even though social drinking context was not a significant mediator, likely due to very few people reporting drinking in isolation in the current sample, the endorsement of drinking for social reasons might partially explain how urgency influences problematic alcohol use. In this way, intervening on social drinking motives might mitigate the effects of urgency on problematic alcohol use, particularly among college students at risk for alcohol use problems
Uji Antagonis Pseudomonas SP. Asal Endofit Perakaran Padi terhadap Penyakit Blas (Pyricularia Oryzae) secara In Vitro
The purpose of this research was to determine the antagonistic bacteria Pseudomonas spp. of paddy roots endophytic against disease blast (Pycularia oryzae) in vitro. This research was conducted at the Laboratory of Agroecology, Faculty of Agriculture, University of Sultan Ageng Tirtayasa on April to June 2015. This research implemented experimental one factor that arranged in Completely Randomized Design with three replications. The treatment consisted of 9 isolates of Pseudomonas sp. which was screened from endophytic roots of paddy plants. The test results showed that antagonistic in vitro testing could inhibit the growth P. oryzae. Inhibition of 9 isolates to the growth Pseudomonas spp. had the significant clear zone. Isolate Ps 17 (58.89%), Ps 22 (54.44%), Ps 37 (52.06%) and Ps 39 (61.42%) have the largest inhibition. The results showed that the bacteria Pseudomonas sp. on this research is potential on controlling disease blast in paddy plant
Diets containing shrimp protein hydrolysates provided protection to European sea bass (Dicentrarchus labrax) affected by a Vibrio pelagius natural infection outbreak
This study was conducted to investigate the effects of the dietary supplementation of shrimp protein hydrolysate (SPH) on somatic growth performance, innate immune response in juvenile European sea bass (Dicentrarchus labrax) and their differential cumulative mortality when affected by a Vibrio pelagius natural infection outbreak. A diet containing 20% fish meal (FM) was used as a control, whereas three other diets differing in the level of FM inclusion (75 and 25% FM replacement by plant protein sources) and the inclusion of the additive (5% FM, 5% FM + 5% SPH and 15% FM + 5% SPH) were tested. After 110 days, there were no statistically significant differences in somatic growth parameters nor proximate composition in fish fed different experimental diets (P > 0.05), while the humoral non-specific immune responses (lysozyme, bacteriolytic and complement activities) were significantly enhanced by the inclusion of SPH in diets (P < 0.05). Additionally, an outbreak of the pathogenic bacteria V. pelagius, a bacterial species previously described as producer of the virulence factor hemolysin, occurred in all experimental tanks (4 replicates per diet) due to crowding and repeated handling stress for fish sorting. Survival rates among different experimental groups ten days after the bacterial epizootic differed depending on the diets, with groups containing SPH showing the best results (P < 0.05). In particular, fish fed the 15% FM + 5% SPH diet showed the highest survival rate (96.4 ± 5.0%), followed by those fed the 5% FM5 + 5% SPH5 (61.8 ± 16.3%). In contrast, survival rates in fish fed diets deprived of the additive (20% FM and 5% FM5 diets) were the lowest ones (32.0 ± 6.7% and 38.2 ± 13.5%, respectively). The present study showed that SPH can be incorporated in aquafeeds with high levels of FM substitution by PP sources without detrimental impact on the somatic growth performance of fish. In addition, the non-specific humoral immunity in seabass and their survival when affected by an epizootic outbreak of V. pelagius were positively affected, which showed the immunomodulatory benefits of shrimp protein hydrolysate to promote health and prevent diseases in fish.info:eu-repo/semantics/acceptedVersio
Vibrio mediterranei, a Potential Emerging Pathogen of Marine Fauna: Investigation of pathogenicity using a bacterial challenge in Pinna nobilis and development of a species‐specific PCR
Aims
Extreme mortality events affecting Pinna nobilis, some associated to Vibrio mediterranei, have depleted many populations of this bivalve. The objective of this study was to demonstrate pathogenicity of V. mediterranei in the host P. nobilis by performing a bacterial challenge in P. nobilis to understand if V. mediterranei has specific virulence in this host. To assist this objective, a secondary objective was to develop a species‐specific DNA diagnostic test.
Methods and Results
P. nobilis collected from local bays were used in a challenge experiment with V. mediterranei (strain IRTA18‐108). Virulence in the host background of P. nobilis was demonstrated at doses of 103 CFUs / animal.
An alignment of published Vibrio spp. atpA sequences was used to design V. mediterranei ‐specific primers. Further, data mining of published literature and V. mediterranei genomes identified multiple virulence‐related genes (vir genes) from which specific primers were designed for PCR detection of selected genes.
Conclusion
V. mediterranei strain IRTA18‐108 is pathogenic in the host P. nobilis . The virulence genes sod, rtx , and mshA were identified in this strain. Temperatures of 24ºC or higher appear to trigger onset of virulence. Sensitivity and specificity of the Vm atpA PCR is useful for diagnosis of Vibriosis in shellfish.
Significance and Impact of the Study
The presence of previously described virulence genes have been confirmed in this strain. The specific Vm atpA PCR assay will aid management of future epizootics of this emerging pathogen of aquatic fauna, and improve surveillance capabilities for mortality events where Vibrios are suspect.info:eu-repo/semantics/acceptedVersio
Identificación de las especies europeas del género Maja (Decapoda: Brachyura: Majidae): análisis de PCR-RFLP de una región del mtADN COI y consideraciones morfológicas
Four species of crabs of the genus Maja have been described along the European coast: M. brachydactyla, M. squinado, M. goltziana and M. crispata. The commercially important species M. brachydactyla and M. squinado achieve the largest body sizes and are the most similar in morphology, and are therefore easily confused. The four species of Maja were identified using a novel morphometric index and a polymerase chain reaction followed by restriction fragment length polymorphism analysis (RFLP). The relationship between carapace length and the distance between the tips of antorbital spines was used to distinguish adults of M. brachydactyla and M. squinado. PCR-RFLP analysis of a partial sequence of the mitochondrial cytochrome oxidase type I (COI) revealed that the four species of the genus Maja can be unambiguously discriminated using the combination of restriction endonucleases enzymes HpyCH4V and Ase I. The molecular identification may be particularly useful in larvae, juvenile and young crabs, when the morphological differences found in adults are not applicable.Cuatro especies del género Maja han sido descritas en las costas europeas: M. brachydactyla, M. squinado, M. goltziana y M. crispata. Las especies M. brachydactyla y M. squinado, que tienen importancia comercial, alcanzan los tamaños más grandes y son morfológicamente muy similares, siendo muy fácil confundirlas. La identificación de las cuatro especies se ha realizado utilizando un nuevo índice morfométrico y un análisis de polimorfismos de fragmentos de restricción (RFLP). La relación entre la longitud del cefalotórax y la distancia entre los extremos distales de las espinas antorbitales se ha utilizado para la diferenciación de los adultos de M. brachydactyla y M. squinado. El análisis PCR-RFLP de una secuencia parcial de la citocromo oxidasa tipo I mitocondrial (COI) indica que las cuatro especies del género Maja pueden ser discriminadas usando una combinación de las endonucleasas HpyCH4V y Ase I. La identificación molecular puede ser particularmente útil en las larvas, juveniles y cangrejos jóvenes, cuando las diferencias morfológicas encontradas en los adultos no son aplicables
Identification of European species of Maja (Decapoda: Brachyura: Majidae): RFLP analyses of COI mtDNA and morphological considerations (Erratum)
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