Genetic differentiation among Atlantic island populations of the brown spiny lobster Panulirus echinatus (Decapoda: Palinuridae)     

Juliana Gaeta  Ivn Acevedo  Violeta Lpez‐Mrquez  Rui Freitas  Raúl Cruz  Rodrigo Maggioni  Rogelio Herrera  Annie Machordom 《水产资源保护:海洋与淡水生态系统》2020,30(5):868-881

1. Declines in Panulirus echinatus Smith, 1869 populations along their wide distribution in the Atlantic Ocean have spurred efforts to improve their fisheries management and conservation. In this study, the genetic structure of these populations is reported for the first time.
2. In a survey of 18 species‐specific polymorphic microsatellite markers, 152 individuals were genotyped from five Atlantic oceanic islands, covering most of the insular distribution range of the species. The analyses revealed that P. echinatus is genetically partitioned into two stocks in the Atlantic Ocean. A highly significant genetic structure was observed between north‐east and south‐west Atlantic populations based on fixation index, discriminant analysis of principal components, and structure and barrier analysis.
3. We suggest that the Equatorial Circulation System represents a biophysical barrier that effectively limits migration among Atlantic subtropical gyre systems, as has been described for other species. Other physical and ecological barriers, such as the Mid‐Atlantic Ridge itself, the distance between the eastern and western sides of the Atlantic (Mid‐Atlantic Barrier) and water mass differences, as well as other biological aspects, may also influence larval dispersal and modulate the insular distribution of this species.
4. The results show the existence of two distinct genetic stocks of P. echinatus and have implications for fisheries management in the Atlantic Ocean, including their independent management according to their individual status. The Cabo Verde and the Canarian populations (north‐east Atlantic) showed the lowest level of genetic variability in comparison with the south‐western populations. A combination of factors that have occurred or are occurring in the Canary Islands, such as overfishing and volcanic eruptions, is likely to explain the reduced abundance of this lobster species in the area.

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Effect of cooling rate on nucleation behavior of milk fat--sunflower oil blends.     

S Martini  M L Herrera  R W Hartel 《Journal of agricultural and food chemistry》2001,49(7):3223-3229

The effect of cooling rate on the crystallization behavior of mixes of high-melting milk fat fraction (HMF) and sunflower oil (SFO) was studied by following nucleation with laser-polarized turbidimetry. The initial crystals were photographed, and their thermal and polymorphic behaviors, as well as chemical composition, were investigated by calorimetry, X-ray diffraction, and capillary gas chromatography. Activation energies of nucleation were calculated using the Fisher-Turnbull equation. Despite small differences in Mettler dropping points for different ratios of SFO to HMF, induction times were significantly different between samples and were shorter at a slow cooling rate for the same supercooling. Rapidly cooled samples required more time at crystallization temperature to crystallize than slowly cooled samples because molecular organization prior to nuclei formation took place under different conditions. Regardless of cooling rate or composition, all crystals were in the beta' polymorph. However, morphology, thermal behavior, and chemical composition showed differences with cooling rate. Activation free energies of nucleation were of the same order of magnitude as those published for hydrogenated SFO.  相似文献   

A class of potent antimalarials and their specific accumulation in infected erythrocytes     

Wengelnik K  Vidal V  Ancelin ML  Cathiard AM  Morgat JL  Kocken CH  Calas M  Herrera S  Thomas AW  Vial HJ 《Science (New York, N.Y.)》2002,295(5558):1311-1314

During asexual development within erythrocytes, malaria parasites synthesize considerable amounts of membrane. This activity provides an attractive target for chemotherapy because it is absent from mature erythrocytes. We found that compounds that inhibit phosphatidylcholine biosynthesis de novo from choline were potent antimalarial drugs. The lead compound, G25, potently inhibited in vitro growth of the human malaria parasites Plasmodium falciparum and P. vivax and was 1000-fold less toxic to mammalian cell lines. A radioactive derivative specifically accumulated in infected erythrocytes to levels several hundredfold higher than in the surrounding medium, and very low dose G25 therapy completely cured monkeys infected with P. falciparum and P. cynomolgi.  相似文献   

A NEW THEORY OF THE ORIGIN AND NATURE OF LIFE     

Herrera AL 《Science (New York, N.Y.)》1942,96(2479):14

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Transcription. Proteasome parts at gene promoters     

Ottosen S  Herrera FJ  Triezenberg SJ 《Science (New York, N.Y.)》2002,296(5567):479-481

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Habitat relations of Rhea americana in an agroecosystem of Buenos Aires Province, Argentina     

L.P Herrera  V.M Comparatore 《Biological conservation》2004,119(3):363-369

The maintenance of wild populations of Greater Rhea (Rhea americana) through effective management requires an understanding of their habitat requirements in terms of vegetation composition and field configuration. We studied the relative influence of some anthropogenic variables (presence of route, house and fences) and resource variables (presence of water source, composition and coverage of plant species, vegetation height and bare soil), on the habitat use by a population of rheas in a cattle ranch of Buenos Aires Province, Argentina. Habitat use was determined indirectly by documenting the number of faeces in summer, autumn-winter and spring 1999. The presence or absence of faeces was related to the measured variables through discriminant analysis that allowed the elaboration of predictive models of habitat use by this species. Contrary to what was expected, those variables related to human activity showed a low predictive value on the habitat use by rheas when compared with resource variables. Rheas preferentially selected the stream area in all seasons and sites with great percent cover of Bupleurum sp., Phyla canescens, Sida leprosa, Plantago lanceolata, Trifolium repens, Lolium multiflorum, Stipa spp., and Stenotaphrum secundatum. Low vegetation height was another important component of rhea's habitat in summer and autumn-winter. The high accuracy level obtained by validation tests of this model supports its utility for the management of rhea populations in other cattle ranches of the region, and to analyze the suitability of other ranches for reintroduction programs.  相似文献   

Modified method for the analysis of free fatty acids in fish     

Bernárdez M  Pastoriza L  Sampedro G  Herrera JJ  Cabo ML 《Journal of agricultural and food chemistry》2005,53(6):1903-1906

The objective of this study was the development of a method for the quantification of free fatty acids (FFA) using less aggressive reactants against the handler and the environment than those used in the classic method of Lowry and Tinsley. The modified procedure is a variation of the Lowry and Tinsley method employing cyclohexane in place of benzene. The use of benzene is prohibited in certain work processes and laboratories, and the competent authority in each country is actively promoting research into harmless or less harmful products that could replace benzene. A comparison with the traditional AOCS titration method for oil analysis was performed. FFA content in mackerel frozen at -10 degrees C was measured according to the three methods over a 12 month period. The results showed similar values, and good correlations were obtained.  相似文献   

Triterpenic compounds from "orujo" olive oil elicit vasorelaxation in aorta from spontaneously hypertensive rats     

Rodriguez-Rodriguez R  Perona JS  Herrera MD  Ruiz-Gutierrez V 《Journal of agricultural and food chemistry》2006,54(6):2096-2102

There is currently a considerable amount of interest in the benefits of certain dietary elements, and in particular of olive oil, in endothelial function and thus in hypertension. "Orujo" or pomace olive oil is obtained from the residues of the olive by a novel centrifugation process, and it is a good dietary source of triterpenic compounds such as oleanolic and maslinic acid, erythrodiol, and uvaol. Until now, there was no information available regarding the properties of these triterpenoids on the vasculature of hypertensive animals. However, in this in vitro study, we have analyzed the vasorelaxation induced by these triterpenoids in isolated aorta from spontaneously hypertensive rats (SHR). The triterpenoids tested induced concentration-dependent vasorelaxation, mostly involving nitric oxide (NO). Indeed, the responses were attenuated by removal of the endothelium or following pretreatment with the NO synthase inhibitor L-NAME. Furthermore, the differences that were observed in the potency of relaxation, the selectivity, and the dependence on the endothelium were attributed to structural features of the triterpenoids. In conclusion, triterpenic components in pomace olive oil induce vasorelaxation of the aorta from SHR, and this effect generally involves endothelial NO.  相似文献   

Genetic variant BDNF (Val66Met) polymorphism alters anxiety-related behavior     

Chen ZY  Jing D  Bath KG  Ieraci A  Khan T  Siao CJ  Herrera DG  Toth M  Yang C  McEwen BS  Hempstead BL  Lee FS 《Science (New York, N.Y.)》2006,314(5796):140-143

A common single-nucleotide polymorphism in the brain-derived neurotrophic factor (BDNF) gene, a methionine (Met) substitution for valine (Val) at codon 66 (Val66Met), is associated with alterations in brain anatomy and memory, but its relevance to clinical disorders is unclear. We generated a variant BDNF mouse (BDNF(Met/Met)) that reproduces the phenotypic hallmarks in humans with the variant allele. BDNF(Met) was expressed in brain at normal levels, but its secretion from neurons was defective. When placed in stressful settings, BDNF(Met/Met) mice exhibited increased anxiety-related behaviors that were not normalized by the antidepressant, fluoxetine. A variant BDNF may thus play a key role in genetic predispositions to anxiety and depressive disorders.  相似文献   

Response of in vitro obtained oil palm and interspecific OxG hybrids to inoculation with Phytophthora palmivora     

Kelly vila‐Mndez  Rodrigo Avila‐Diazgranados  Alonso Pardo  Mariana Herrera  Greicy Sarria  Hernan Mauricio Romero 《Forest Pathology》2019,49(2)

Bud rot (BR) disease caused by Phytophthora palmivora is the most devastating disease in oil palm cultivation in America. Oil palms that survived BR epidemics were found in areas highly devastated by the disease; these palms were introduced into Cenipalma's in vitro micropropagation (cloning programme). A severity scale was developed for in vitro palms from five ortets inoculated with two different P. palmivora isolates. Then, eight ortets of Elaeis guineensis and two ortets of the OxG interspecific hybrid were evaluated in two inoculation trials under chamber growth conditions. The clone performance response was consistent with that reported in the field for the corresponding ortets, and two contrasting ortets, one susceptible (ortet 57) and one resistant (ortet 34) were identified. We monitored and compared defence responses to P. palmivora in the contrasting ortets. An increase in reactive oxygen species (ROS) production after inoculation with the pathogen was observed, with higher accumulation of H₂O₂ in the resistant plants. Catalase (CAT) activity in resistant plants increased after inoculation with the pathogen from 24 hr post‐infection (hpi) and remained high during the observation time. In the susceptible ortets, there was a significant increase on catalase activity only at 48 hpi. Peroxidase (POS) activity increased in clones from both susceptible and resistant ortets, but the increase was much greater in the susceptible ones. Phenylalanine ammonia lyase activity increased in response to inoculation, and these increases were greater in clones of the susceptible ortet than in clones of the resistant ortet.  相似文献