90 research outputs found

    El estrés en los peces. II-Factores estresantes comunes en los peces cultivados

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    Los peces cultivados están sometidos habitualmente a una serie de condiciones negativas que provienen tanto de las características físico-químicas de su medio ambiente, como de las operaciones propias del cultivo. En este trabajo se revisan los principales factores causantes de estrés a los peces, tales como calidad del agua (temperatura, pH, oxígeno disuelto, contaminantes, etc.), manipulación, tratamiento de enfermedades y anestesi

    El estrés en los peces. II-Factores estresantes comunes en los peces cultivados

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    Fish in intensive culture are affected both by the characteristics of aquatic environment itself and by the stress of hatchery conditions. This paper review the more common causes of stress in fish such as water quality (temperature, pH, dissolved oxigen, contaminants, etc.), handling, disease treatments and anaesthesia.Los peces cultivados están sometidos habitualmente a una serie de condiciones negativas que provienen tanto de las características físico-químicas de su medio ambiente, como de las operaciones propias del cultivo. En este trabajo se revisan los principales factores causantes de estrés a los peces, tales como calidad del agua (temperatura, pH, oxígeno disuelto, contaminantes, etc.), manipulación, tratamiento de enfermedades y anestesia

    The neovolcanic axis is a barrier to gene flow among Aedes aegypti populations in Mexico that differ in vector competence for Dengue 2 virus.

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    The Neovolcanic axis (NVA) traverses Mexico at the 19th parallel and is considered to be a geographic barrier to many species. We have demonstrated that the intersection of the NVA with the coast in Veracruz state is a barrier to gene flow in Ae. aegypti. This was unexpected because the intersection of the NVA with the Pacific Coast is not a barrier to gene flow. Further studies to identify the actual mechanism(s) that is(are) contributing to the lack of gene flow will provide important information on the trafficking potential of Ae. aegypti, which will be of great value to Ae. aegypti control programs. There are significant differences in vector competence for dengue virus between mosquitoes north and south of the NVA, but the epidemiological significance of these finding remains to be determined. Future studies will determine if, for example, the genes that condition midgut infection and vector competence of Ae. aegypti populations provide biomarkers for risk of dengue transmission. Such biomarkers could be of great value to control programs in resource limited environments by allowing targeting of vector control efforts to areas at most risk for epidemic dengue and dengue hemorrhagic fever

    Synthesis and in vitro antiprotozoal activity of some 2- amino-4-phenyloxazole derivatives

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    Purpose: To prepare some 2-amino-4-(p-substituted phenyl)-oxazole derivatives and to evaluate their in vitro antiprotozoal activity against Giardia lamblia and Trichomonas vaginalis.Methods: The 2-amino-4-(p-substituted phenyl)-oxazoles (a-g) were synthesized by microwave (MW) irradiation of mixtures of p-substituted 2-bromoacetophenones and urea in dimethylformamide (DMF). All compounds were identified by 1H and 13C nuclear magnetic resonance (NMR) spectroscopy and lowand high-resolution mass spectrometry (HRMS). NMR assignments were made based on heteronuclear single quantum coherence (HSQC) and heteronuclear multiple bond correlation (HMBC) experiments. Each synthesized compound’s melting point was determined. Antiprotozoal activity against Giardia intestinalis and Trichomonas vaginalis was quantified using a rigorous and sensitive subculture method. The commercial drug, metronidazole, was used as positive control. The 50 % inhibitory concentration (IC50) of the antiprotozoal agents for each protozoa was determined.Results: Seven 2-amino-4-(p-substituted phenyl)-oxazoles (a-g) were synthesized. The most active compounds against G. lamblia was 2-amino-4-(p-benzoyloxyphenyl)-oxazole (3d) with an IC50 of 1.17 μM, while compound 3e (2-amino-4-(p-bromophenyl)-oxazole) showed the highest anti-trichomonal activity (IC50, 1.89 μM).Conclusion: The in vitro antigiardial activity of 2-amino-4-(p-benzoyloxyphenyl) oxazole was higher than that exhibited by metronidazole; however, it is necessary increase the number of synthetic derivatives in order to be able to determine their structure-activity relationship.Keywords: Antiprotozoal, 2-Amino-4-phenyl-oxazoles, Giardia lamblia, Trichomonas vaginali

    Is type of work associated with physical activity and sedentary behaviour in women with fibromyalgia A cross-sectional study from the al-Ándalus project

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    Objectives To analyse the association between the type of work (productive vs reproductive work) and the levels of physical activity and sedentary behaviour in women with fibromyalgia. Method This cross-sectional study involved 258 women with fibromyalgia from southern Spain. Of them, 55% performed reproductive work (unpaid, associated with caregiving and domestic roles) exclusively, while 45% had productive job (remunerated, that results in goods or services). Physical activity of light, moderate and vigorous intensity in the leisure time, at home, at work, and totally were measured through the leisure time physical activity instrument and with the physical activity at home and work instrument, respectively. Sedentary behaviour was measured by the Sedentary Behaviour Questionnaire. Results After adjusting for age, fat percentage, education level and marital status, the multivariate analysis of covariance model informed the existence of significant differences between type of work groups (p<0.001). Women with productive work engaged in more light physical activity at work (mean difference =448.52 min; 95 % CI 179.66 to 717.38; p=0.001), and total physical activity of light (809.72 min; 535.91 to 1085.53; p<0.001) and moderate (29

    Parallel evolution of vgsc mutations at domains IS6, IIS6 and IIIS6 in pyrethroid resistant Aedes aegypti from Mexico

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    Aedes aegypti is the primary urban mosquito vector of viruses causing dengue, Zika and chikungunya fevers –for which vaccines and efective pharmaceuticals are still lacking. Current strategies to suppress arbovirus outbreaks include removal of larval-breeding sites and insecticide treatment of larval and adult populations. Insecticidal control of Ae. aegypti is challenging, due to a recent rapid global increase in knockdown-resistance (kdr) to pyrethroid insecticides. Widespread, heavy use of pyrethroid spacesprays has created an immense selection pressure for kdr, which is primarily under the control of the voltage-gated sodium channel gene (vgsc). To date, eleven replacements in vgsc have been discovered, published and shown to be associated with pyrethroid resistance to varying degrees. In Mexico, F1,534C and V1,016I have co-evolved in the last 16 years across Ae. aegypti populations. Recently, a novel replacement V410L was identifed in Brazil and its efect on vgsc was confrmed by electrophysiology. Herein, we screened V410L in 25 Ae. aegypti historical collections from Mexico, the frst heterozygote appeared in 2002 and frequencies have increased in the last 16 years alongside V1,016I and F1,534C. Knowledge of the specifc vgsc replacements and their interaction to confer resistance is essential to predict and to develop strategies for resistance management

    Pagurta: An interspecific hybrid of common seabream Pagrus pagrus (L., 1758) female and banded seabream males Pagrus auriga Valenciennes, 1843 male: phenotypic and molecular characterization

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    Hybrids are of great interest in aquaculture. In the present study, we report for the first time an interespecific hybrid between common seabream Pagrus pagrus (L., 1758) females and red banded seabream Pagrus auriga (Valenciennes, 1843) males, which has been named the pagurta. This hybrid was detected in natural spawns during the period from March to April 2004. Phenotipically, the hybrid possessed morphological and meristic characteristics of both parental species. Mitochondrial and nuclear (microsatellite and satellite) molecular markers were used to confirm they were hybrids. The reciprocal cross was not detected.Los híbridos suscitan gran interés en la acuicultura. Sin embargo, su aplicación industrial en espáridos ha estado limitada por las dificultades técnicas que ocasiona su desarrollo. En este trabajo se describe el nacimiento no inducido, o espontáneo, de híbridos entre pargo Pagrus pagrus (L., 1758) y hurta Pagrus auriga Valenciennes, 1843 cuando dichas especies coexisten en un mismo tanque. Estos híbridos surgieron durante los meses de marzo y abril de 2004, cuando se registraron las puestas más abundantes de ambas especies. Fenotípicamente, presentaron características propias de ambas especies parentales. La aplicación de marcadores mitocondriales y nucleares (microsatélite y satélite) permitieron confirmar que eran híbridos intergenéricos de P. pagrus (♀ ) ˟ P. auriga (♂ ) a los que se denominó pagurta. El cruce recíproco no se detectó.Instituto Español de Oceanografí

    A chromosome-level genome assembly enables the identification of the follicule stimulating hormone receptor as the master sex determining gene in the flatfish Solea senegalensis

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    Sex determination (SD) shows huge variation among fish and a high evolutionary rate, as illustrated by the Pleuronectiformes (flatfishes). This order is characterized by its adaptation to demersal life, compact genomes and diversity of SD mechanisms. Here, we assembled the Solea senegalensis genome, a flatfish of great commercial value, into 82 contigs (614 Mb) combining long- and short-read sequencing, which were next scaffolded using a highly dense genetic map (28,838 markers, 21 linkage groups), representing 98.9% of the assembly. Further, we established the correspondence between the assembly and the 21 chromosomes by using BAC-FISH. Whole genome resequencing of six males and six females enabled the identification of 41 SNP variants in the follicle stimulating hormone receptor (fshr) consistent with an XX / XY SD system. The observed sex association was validated in a broader independent sample, providing a novel molecular sexing tool. Fshr displayed differential gene expression between male and female gonads from 86 days post-fertilization, when the gonad is still an undifferentiated primordium, concomitant with the activation of amh and cyp19a1a, testis and ovary marker genes, respectively, in males and females. The Y-linked fshr allele, which included 24 non-synonymous variants and showed a highly divergent 3D protein structure, was overexpressed in males compared to the X-linked allele at all stages of gonadal differentiation. We hypothesize a mechanism hampering the action of the follicle stimulating hormone driving the undifferentiated gonad toward testis.info:eu-repo/semantics/acceptedVersio
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