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In August 2018, symptoms of apical and basal rot resembling those caused by Sclerotinia sclerotiorum infection were observed in a commercial Brussels sprouts field in North Patagonia, Argentina. The incidence of apical and basal rot was 23.30% and 2.30%, respectively. Carpogenic germination of sclerotia was detected in shaded, highly humid soil areas. To our knowledge, this is the first report of carpogenic germination of sclerotia from S. sclerotiorum in North Patagonia.

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El género es una construcción psicosocial referida a los roles, comportamientos, expresiones e identidades socialmente construidos de niñas, mujeres, niños, hombres y personas con diversidad de género, mientras que el sexo se relaciona con los atributos biológicos de una mujer o un hombre. Aun cuando los términos "sexo" y "género" suelen utilizarse de forma binaria, existe una diversidad considerable en la forma en que los individuos y los grupos los entienden, experimentan y expresan. En esta revisión narrativa se describen algunos aspectos relevantes acerca de la diferencia subjetiva que existe y favorece a los hombres frente a las mujeres en el ámbito de las ciencias e investigación, iniciando desde una perspectiva histórica a la luz de los movimientos feministas. En particular, se describe a la mujer en cuanto investigadora y creadora de conocimiento científico, como también en su calidad de sujeto de análisis. Se analizan además algunos conflictos derivados del sesgo de sexo aplicados a la investigación biomédica, y se entregan casos que ejemplifican el desmedro que ha acompañado históricamente al género femenino en este ámbito, su desconocimiento y poco reconocimiento cultural. Esta revisión es la última entrega de una serie metodológica sobre conceptos generales en bioestadística y epidemiología clínica desarrollada por la Cátedra de Metodología de la Investigación Científica de la Escuela de Medicina de la Universidad de Valparaíso, Chile, que pretende abordar una temática contingente y transversal a toda la investigación científica.

Gender is a psychosocial construct referring to the socially built roles, behaviors, expressions and identities of girls, women, boys, men and people with gender diversity, while sex is related to the biological attributes of a woman or a man. Even though the terms "sex" and "gender" are often used in a binary way, there is considerable diversity in the way individuals and groups understand, experiment and express them. This narrative review describes some relevant aspects of the subjective difference that exists and favors men over women in the fields of sciences and research, starting from a historical perspective in the light of feminist movements. In particular, women are described as researchers - crea-tors of scientific knowledge, as well as the subjects of analysis. Some conflicts arising from sex bias, applied to biomedical research, are also analyzed, and cases are delivered that exemplify the disarray that has historically accompanied the female gender in this area, its ignorance and little cultural recognition. This review is the last article in a methodological series on general concepts in biostatistics and clinical epidemiology developed by the Chair of Methodology of Scientific Research of the School of Medicine of the Universidad de Valparaiso, Chile, which aims to address a contingent and cross-cutting theme to all scientific research.

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Las revisiones sistemáticas de literatura constituyen una de las principales metodologías utilizadas en la validación de las propiedades saludables de los alimentos, o factores alimentarios, que afectan la fisiología humana. Esta herramienta, basada en la evidencia obtenida a través de ensayos clínicos aleatorizados realizados con un diseño experimental adecuado, permite concluir si existe una relación causal entre el producto consumido y un efecto beneficioso para la salud, principio que sustenta el calificativo de los alimentos como "funcionales". Se presentan y analizan las características y la forma en la que las revisiones sistemáticas pueden contribuir a que las agencias regulatorias aprueben un mensaje saludable (health claim), dirigido al consumidor.

Systematic literature reviews are one of the main methodologies used to substantiate the health properties of foods and food constituents purported to affect human physiology. This tool is based on scientific evidence obtained from correctly performed randomized controlled trials. Systematic reviews make it possible to conclude whether there is a causal relationship between food consumed and health effects observed, thus supporting the use of the term "functional foods." We present and analyze the prinicpal characteristics of, and ways by which, systematic reviews can contribute to the regulatory approval of health claims directed to consumers.

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The spatial distribution and temporal variation of 11 species of Tropisternus were analyzed in two permanent ponds located in the province of Corrientes, Argentina. Samples were collected every 15 days, between October 2010 and March 2011. The species recorded were Tropisternus collaris (Fabricius), Tropisternus ovalis Castelnau, Tropisternus laevis (Sturm), Tropisternus lateralis limbatus (Brullé), Tropisternus longispina Fernández & Bachmann, Tropisternus carinispina Orchymont, Tropisternus bourmeisteri Fernández & Bachmann, Tropisternus apicipalpis (Chevrolat), Tropisternus dilatatus Bruch, Tropisternus obesus Bruch, and Tropisternus ignoratus Knisch. The first four were present in higher proportions than the remaining during most of the study period. The spatial distribution of individuals was mostly related to the homogeneity or heterogeneity of the ecosystem in relation to microhabitats with aquatic vegetation: In ponds with different microhabitats, individuals were mainly aggregated, whereas in ponds with homogenous features, individuals were randomly distributed. However, when species were analyzed individually, the spatial distribution and the use of microhabitat by each species were different with respect to preference and behavior.

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New host association: Polybia scutellaris (Hymenoptera, Vespidae) parasitized by Melaloncha (Diptera, Phoridae). The genus Melaloncha Brues is a large assemblage of New World, parasitoid phorid flies. They are parasitoids of Apoidea bees. However, here we present the first record of a wasp parasitized by Melaloncha sp. The new host is Polybia scutellaris (White), a neotropical eusocial wasp. The parasitized wasp was found in an urban park near the city of La Plata, Buenos Aires, Argentina. It appears that the genus Melaloncha parasitizes a wider range of social Hymenoptera than currently known.

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Putative mechanisms of action associated with the biocontrol capacity of four yeast strains (Cryptoccocus albidus NPCC 1248, Pichia membranifaciens NPCC 1250, Cryptoccocus victoriae NPCC 1263 and NPCC 1259) against Penicillium expansum and Botrytis cinerea were studied by means of in vitro and in situ assays. C. albidus(YP), a commercial yeast was also evaluated for comparative purposes. The yeast strains exhibited a variety of different mechanisms including: wound colonization, germination inhibition, biofilm formation, secretion of killer toxins, competition for nutrient and secretion of hydrolytic enzymes (protease, chitinase and glucanase). The relationship between strains (and their associated antagonist mechanisms) and in situ antagonist activity was also evaluated. Results indicate that mechanisms such as production of hydrolytic enzymes, the ability for colonization of wounds, production of killer toxin and inhibition of germination are the most important for biocontrol activity. Our study indicate that multiple modes of action may explain why P. membranifaciens NPCC 1250 and C. victoriae NPCC 1263 provided excellent control of postharvest pears disease.

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To reduce the use of fungicides, biological control with yeasts has been proposed in postharvest pears. Most studies of antagonists selection have been carried out at room temperature. However, in regions like North Patagonia where fruits are stored at -1/0 °C during 5-7 months the selection of potential antagonist agents must be carried out at low temperature. In this study, 75 yeast cultures were isolated from healthy pears from two Patagonian cold-storage packinghouses. Aureobasidium pullulans, Cryptococcus albidus, Cryptococcus difluens, Pichia membranifaciens, Pichia philogaea, Rhodotorula mucilaginosa and Saccharomyces cerevisiae yeast species were identified. Additionally, 13 indigenous isolates of Penicillium expansum and 10 isolates of Botrytis cinerea were obtained from diseased pears, characterized by aggressiveness and tested for sensitivity to postharvest fungicides. The yeasts were pre-selected for their ability to grow at low temperature. In a first biocontrol assay using the most aggressive and the most sensitive isolate of each pathogen, two epiphytic isolates of A. pullulans and R. mucilaginosa were the most promising isolates to be used as biocontrol agents. They reduced the decay incidence by P. expansum to 33% and the lesion diameter in 88% after 60 days of incubation in cold. Foreign commercial yeast used as a reference in assays, only reduced 30% of lesion diameter in the same conditions. Yeasts were not able to reduce the incidence of B. cinerea decay. The control activity of the best two yeasts was compared with the control caused by the fungicides in a second bioassay, obtaining higher levels of protection against P. expansum by the yeasts. These two regional yeasts isolates could be promising tools for the future development of commercial products for biological control.

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Early-life environmental events, such as the handling procedure, can induce long-lasting alterations upon several behavioral and neuroendocrine systems. However, the changes within the pups that could be causally related to the effects in adulthood are still poorly understood. In the present study, we analyzed the effects of neonatal handling on behavioral (maternal odor preference) and biochemical (cyclic AMP response element-binding protein (CREB) phosphorylation, noradrenaline (NA), and serotonin (5-HT) levels in the olfactory bulb (OB)) parameters in 7-day-old male and female rat pups. Repeated handling (RH) abolished preference for the maternal odor in female pups compared with nonhandled (NH) and the single-handled (SH) ones, while in RH males the preference was not different than NH and SH groups. In both male and female pups, RH decreased NA activity in the OB, but 5-HT activity increased only in males. Since preference for the maternal odor involves the synergic action of NA and 5-HT in the OB, the maintenance of the behavior in RH males could be related to the increased 5-HT activity, in spite of reduction in the NA activity in the OB. RH did not alter CREB phosphorylation in the OB of both male and females compared with NH pups. The repeated handling procedure can affect the behavior of rat pups in response to the maternal odor and biochemical parameters related to the olfactory learning mechanism. Sex differences were already detected in 7-day-old pups. Although the responsiveness of the hypothalamic-pituitary-adrenal axis to stressors is reduced in the neonatal period, environmental interventions may impact behavioral and biochemical mechanisms relevant to the animal at that early age.

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Nervous system is second to adipose tissue in containing the highest lipid concentration. Membrane phospholipids possess a high content of long chain polyunsaturated fatty acids (LCPUFA) of the n-3 and n-6 families, derived from the corresponding essential fatty acids. Docosahexaenoic acid (22:6n-3) is found in the highest concentrations in the gray matter and the photoreceptors of the retina. n-3 LCPUFA deficiency in infants, mainly if born preterm, modifies neural functions causing learning disabilities and visual function abnormalities. The adequate lipid nutrition of the mother before and during pregnancy and in breast feeding determine the lipid transfer of fatty acids to the fetus and infant, respectively. LCPUFA are conditionally essential in preterm infants, born with lower lipid depots. The formulation of infant formulas, mainly for preterm babies, should include adequate proportions of n-3 and n-6 LCPUFA.

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This study was undertaken to compare the effects of four oils: corn (C), olive (O), hazelnut (H) or fish (F), and the intake of two supplements: cholesterol, 1% (Ch) or dl-alpha-tocopherol acetate, 500 mg/kg, and beta-carotene, 30 mg/kg (V), on liver microsomal fluidity, cyt P450 content and aniline hydroxylase (AH), aminopyrine-N-dimethylase (AND) and UDP-glucuronyltransferase (UDP-GT) activities. Male Sprague-Dawley rats (n = 6/group) were fed semipurified diets containing 15% oil, without or with Ch or V, for 20 days. Dietary intake and feed efficiency were lower in rats fed F. Relative liver weight was higher in animals fed F, similar in O and H, and lower in the group fed C. The intake of V increased feed intake in C+V group and decreased the relative liver weight of F+V group, which also decreased with the intake of F+Ch. Ch intake increased the relative liver weight in all groups consuming vegetable oils. Cyt P450 content was higher in rats fed F. Decreased cyt P450 content was observed in C+Ch and F+Ch groups, while it augmented in H+Ch group. Mixture V increased cyt P450 in rats fed C+V, F+V and O+V. The highest membrane fluidity was observed in rats fed F. Fluidity was also higher in group H versus O or C. The intake of Ch decreased microsomal fluidity in all groups, while V induced an increase in microsomal fluidity in group O+V. Rats fed F exhibited higher enzyme activities. AND activity increased with V only in rats fed H+V, while AH activity increased with V intake in groups F+V and O+V. In the C+V group, fluidity was not affected by V, while the cyt P450 content and UDP-GT activity increased. The O+V group exhibited lower UDP-GT activity and higher fluidity and cyt P450 content. The activity of AH decreased in groups F+Ch and C+Ch. UDP-GT activity was higher in rats fed F. It diminished after the intake of Ch in H+Ch and F+Ch. These results indicate that although AH and AND act in the same microsomal metabolic pathway, their localization into the membrane may be determinant of their activity and the response to dietary lipids. It is shown that F intake exerts the most significant effects upon liver microsomal properties, e.g. higher fluidity, cyt P450 content and enzymatic activities, an effect that prevails over the intake of the supplements tested.

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We examined the effects of vitamin supplement on the vascular smooth muscle response of rats fed four different oil diets, after a 20-day feeding period. Male Sprague Dawley rats were fed diets containing 15% of each hazelnut, corn, olive or fish oils, with/without 30 mg/kg beta-carotene and 500 mg/kg dl-alpha-tocopherylacetate. After the feeding period, plasma retinol, alpha-tocopherol, cholesterol, HDL and triacylglyceride concentrations and aortic ring segment responses to KCl (70 mM), phenylephrine and acetylcholine (maximal tension, maximal relaxation and pD2 or -log ED50) were measured. The intake of vitamin-supplemented diets increased plasma alpha-tocopherol levels in rats fed hazelnut or fish oil, while retinol concentration was unaffected. Also, the vitamin supplement counteracted the specific hypercholesterolemic effect of hazelnut oil intake. The addition of a vitamin supplement augmented acetylcholine pD2 values in aortic ring segments of rats fed corn oil (p < 0.001), revealing that arteries were more prone to induced relaxation under this dietary condition. It also lowered the maximal ring tension in response to phenylephrine in rats fed hazelnut or olive oil. These results indicate that the intake of alpha-tocopherol and beta-carotene supplement can modulate the effect of dietary fat type on aortic ring segment responses to pharmacological agents in the rat.

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Sea-lion oil (SO) is used as a dietary supplement in the treatment of cardiovascular disease. The effects of SO on plasma lipid concentration and liver lipid histochemistry were compared with those of corn oil (CO). Male Sprague-Dawley rats were fed diets containing 15% (w/w) SO or CO with or without 1% cholesterol for 25 days. Compared with rats fed CO, SO-fed rats showed lower plasma cholesterol levels (P < 0.001), high-density lipoproteins (HDL) (P < 0.05), very-low-density lipoproteins (P < 0.05), triglycerides (P < 0.05) and total lipids (P < 0.05). Rats fed SO and cholesterol had lower plasma concentrations of cholesterol (P < 0.001) and HDL (P < 0.05) than those of animals fed CO. Alterations in liver cytology were observed in rats fed SO, including a differential accumulation of lipids in the canalicular regions of hepatocytes and a high density of lipid vesicles in hepatic lobule triads. The results indicated that, compared with CO, SO reduces plasma lipid levels and causes histochemical changes associated with an increased excretion of lipids from the liver.

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The comparative effects of dietary level and time of feeding corn (CO) and rose hip (RHO) oils on bile and plasma lipid composition were studied. 48 males Sprague Dawley rats were divided in two groups fed semipurified diets containing CO or RHO as the only lipid source. Groups of 6 rats were fed ad libitum diets containing 5% or 15% vegetable oil during 15 or 60 days. Food intake was not dependent on the type of oil, and was higher in 15% oil diets (p < 0.01), increasing with time of feeding (p < 0.001). Bile flow was similar in all groups. Biliary concentrations of cholesterol, phospholipids and bile acids were affected by the time of feeding (p < 0.001). Plasma total and high density lipoprotein (HDL) cholesterol levels were higher in 15% oil fed rats (p < 0.05). Triglycerides concentrations were similar in all groups. The results indicate that oil concentration and time of feeding were the most important variables affecting the lipid composition of rats, independently of the fatty acid composition of the ingested fats.

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