RESUMEN

The 1965 book Hysteria: The History of a Disease, by the German American historian Ilza Veith, certainly represented a milestone in the historiography of hysteria. Praised at first as an innovative work, unprecedented in its comprehensiveness and scholarship, it became, over time, object of multiple criticisms regarding its omissions, its psychoanalytic bias, and the teleological character of its approach. This article aims at pondering these contrasting assessments and discussing the historical significance of Veith's work from a contemporary perspective. To this end, a brief overview of historical studies on hysteria before Veith is outlined. This overview is followed by a descriptive and critical presentation of her work, a discussion of certain aspects of its reception and, as conclusion, an evaluation of her contribution and legacy to this research field.

Resumos O livro Hysteria: The History of a Disease, da historiadora germano-americana Ilza Veith, publicado em 1965, representou certamente um marco na historiografia da histeria. Elogiado inicialmente como uma obra inovadora e sem precedentes em sua abrangência e erudição, tornou-se com o tempo objeto de múltiplas críticas com relação a suas omissões, ao viés psicanalítico e ao caráter teleológico de sua abordagem. O objetivo deste artigo é ponderar essas avaliações contrastantes e discutir a significação histórica do livro de Veith com base em uma perspectiva contemporânea. Para tanto, traça-se um breve panorama da situação dos estudos históricos sobre a histeria antes de Veith. A seguir, é feita uma apresentação descritiva e crítica de seu trabalho, discutem-se certos aspectos de sua recepção e, a título de conclusão, ensaia-se uma avaliação de sua contribuição e de seu legado para esse campo de pesquisas.

Le livre Hysteria: The History of a Disease, de l'historienne germano-américaine Ilza Veith, publié en 1965, a certainement représenté un tournant dans l'historiographie de l'hystérie. D'abord acclamée comme une œuvre innovante et sans précédent par son exhaustivité et son érudition, elle est devenue au cours du temps l'objet de multiples critiques concernant ses omissions, son parti pris psychanalytique et le caractère téléologique de sa démarche. L'objectif de cet article est de réfléchir sur ces évaluations contrastées et de discuter de l'importance historique du livre de Veith dans une perspective contemporaine. À cette fin, on fournit d'abord un bref aperçu de l'état des études historiques sur l'hystérie avant Veith et ensuite une présentation descriptive et critique de son travail. On discute d'ailleurs certains aspects de sa réception et, en guise de conclusion, on présente une évaluation de sa contribution et de son héritage dans ce domaine de recherche.

El libro Hysteria: The History of a Disease, de la historiadora germano-estadounidense Ilza Veith, publicado en 1965, representó, sin duda alguna, un marco en la historiografía de la histeria. Elogiada inicialmente como una obra innovadora y sin precedentes por su amplitud y erudición, con el tiempo se convirtió en objeto de múltiples críticas por sus omisiones, por el sesgo psicoanalítico y por el carácter teleológico de su enfoque. El objetivo de este artículo es ponderar estas evaluaciones contrastantes y discutir la importancia histórica del libro de Veith desde una perspectiva contemporánea. Para ello, se traza un breve recorrido por el estado de los estudios históricos sobre la histeria anteriores a Veith. A continuación, se realiza una presentación descriptiva y crítica de su obra, se discuten algunos aspectos de su recepción y, a modo de conclusión, se ensaya una evaluación de su contribución y legado a este campo de investigación.

RESUMEN

This study addresses gaps in our understanding of pre-fertilization and archegonia development and reinterprets embryonic ontogenesis from Burlingame (Bot Gaz 59:1-39, 1915) to the present based on timescale and structural features allowing us to determine functionally and developmentally accurate terminology for all these stages in A. angustifolia. Different from previous reports, only after pollination, pre-fertilization tissue development occurs (0-13 months after pollination (MAP)) and gives rise to a mature megagametophyte. During all this period, pollen is in a dormant state at the microphyla, and pollen tube germination in nucellus tissue is only observed at the stage of archegonia formation (13 MAP) and not at the free nuclei stage as reported before. For the first time, 14 months after pollination, a fertilization window was indicated, and at 15 MAP, the polyzygotic polyembryony from different archegonia was also seen. After that, subordinated proembryo regression occurs and at least three embryonic developmental stages of dominant embryo were characterized: proembryogenic, early embryogenic, and late embryogenic (15-23 MAP). Along these stages, histochemical and ultrastructural analyses suggest the occurrence of cell death in suspensor and in cap cells of dominant embryo that was not previously reported. The differentiation of meristems, procambium, pith, and cortex tissues in late embryogenic stage was detailed. The morphohistological characterization of pre-fertilization and embryonic stages, together with the timescale of megastrobili development, warranted a referential map of female reproductive structure in this species.

Asunto(s)

RESUMEN

Uma observação das narrativas sobre a história da histeria revela que nem sempre aqueles que as elaboraram levaram em consideração o aspecto fundamentalmente historiográfico da proposta, tomando inferências como se fossem fatos históricos. Esse deslize originou narrativas que não deveriam ser classificadas como história, mas, mais apropriadamente, como mitologias. Com frequência, a trajetória da histeria começa na medicina egípcia, segue em um continuum por Hipócrates, pelas bruxas da Idade Média, pelos vapores do Iluminismo, até chegar à Salpêtrière, a Charcot e, em seguida, a Freud. Porém, do ponto de vista historio-gráfico (e evitando o anacronismo), esse curso pode não ser tão seguro. O artigo revê essa trajetória e propõe que a história da histeria implicaria dois estágios, separando-se a histeria doença do útero da histeria neurose. Uma ponte entre as duas concepções teria sido estabelecida por Thomas Sydenham, em 1682, no Epistolary discourse to the learned Dr. William Cole.

Analysis of the narratives on the history of hysteria reveals that those who elaborated them did not always take into account the fundamentally historiographical aspect of that proposal, and some inferences were considered as historical facts. This error gave rise to narratives that should not be classified as histories, but rather as mythologies. All too often, the historical trail of hysteria is taken to begin in Egyptian medicine, and then follow a continuum: to Hippocrates, the witches of the Middle Ages, the Enlightenment, the Salpêtrière, Charcot, and then Freud. However, from a historiographical point of view (and avoiding anachronism), this appears not to be the reliable sequence. This paper reviews that trajectory and proposes that a history of hysteria would unfold in two stages, distinguishing hysteria, as a disease of the uterus, from hysteria, as a neurosis. In such a proposal, a bridge between the two conceptions would have been established by Thomas Sydenham in 1682, with the Epistolary Discourse to the Learned Dr. William Cole.

La observación de los relatos sobre la historia de la histeria revela que quienes los elaboraron, no siempre han tenido en cuenta el aspecto fundamentalmente historiográfico de la propuesta, tomando inferencias como hechos históricos. Este desliz dio lugar a narraciones que no deberían clasificarse como historia, sino como mitologías. El trayecto histórico de la histeria comienza a menudo en la medicina egipcia, sigue en un continuum por Hipócrates, las brujas de la Edad Media, los vapores del Iluminismo, hasta llegar a Salpêtrière, Charcot y luego Freud. Sin embargo, desde un punto de vista historiográfico, y evitando el anacronismo, este camino puede no ser tan seguro. En este artículo se revisa esta trayectoria y se propone que la historia de la histeria involucraría dos etapas, separando la histeria, enfermedad del útero, de la histeria, una neurosis. Un puente entre las dos concepciones habría sido establecido por Thomas Sydenham, en 1682, en el Epistolary Discourse to the Learned Dr. William Cole.

L'observation des récits sur l'histoire de l'hystérie révèle que ceux qui les ont élaborés n'ont pas toujours pris en compte l'aspect fondamentalement historiographique de la proposition, en prenant certaines inférences comme s'elles étaient des faits historiques. Cette omission a donné lieu à des récits qui ne devraient pas être considérés comme de l'histoire, mais plutôt comme des mythologies. Le chemin historique de l'hystérie commence souvent dans la médecine égyptienne, suit un continuum à travers Hippocrate, les sorcières du Moyen Age, les vapeurs de l'Illuminisme, la Salpêtrière, Charcot et, ensuite, Freud. Cependant, d'un point de vue historiographique (et en évitant l'anachronisme), cette voie pourrait ne pas être si sûre. L'article reformule cette trajectoire et propose que l'histoire de l'hystérie se déroule en deux étapes, en séparant l'hystérie, la maladie de l'utérus, de l'hystérie que l'on appelle la névrose. Un pont entre les deux conceptions aurait été établi par Thomas Sydenham, en 1682, dans le Epistolary Discourse to the Learned Dr. William Cole.

RESUMEN

This is the first study to describe in a timescale morphohistological and ultrastructural characteristics of fruit (cypsela) and seed development in Trichocline catharinensis, which was completed 21 days after anthesis (DAA). At anthesis, we identified an ovary with three differentiated regions, including the inner epidermis, inner part, and outer epidermis. The mature ovule showed an integument with the outer epidermis, integumentary parenchyma, and endothelium. Cells around the endothelium form the periendothelial zone with thick cell walls that showed Periodic acid-Schiff (PAS)-positive reaction. The periendothelial zone and endothelium showed degradation of the cells during embryogenesis. The main stages of embryo development from fecundation through mature seed were identified. The ripe cypsela showed the pericarp (exocarp), seed coat (exotesta), and remaining endosperm surrounding the embryo. Mature embryos were straight with shoot apical meristem (SAM), and root apical meristem (RAM) was separated by the hypocotyl. Light microscopy (LM) and transmission electron microscopy (TEM) analyses indicate cells with characteristics of meristem cells, as well as proteins and lipid bodies and mitochondria with few cristae in cotyledon cells. Our findings provide insight into taxonomic and physiological studies by detailing cypsela and seed ontogenesis from an endemic and vulnerable Asteraceae from southern Brazil. This study is also a starting point for establishing the biological criteria for seed harvesting and future studies of seed physiology and conservation of plant genetic resource.

Asunto(s)

RESUMEN

Acanthophora spicifera (M.Vahl) Børgesen is a macroalga of great economic importance. This study evaluated the antioxidant responses of two algal populations of A. spicifera adapted to different abiotic conditions when exposed to ultraviolet-A+ultraviolet-B radiation (UV-A+UV-B). Experiments were performed using the water at two collection points for 7 days of acclimatization and 7 days of exposure to UVR (3 h per day), followed by metabolic analyses. At point 1, water of 30 ± 1 practical salinity unit (psu) had concentrations of 1.06 ± 0.27 mm NH 4 + , 8.47 ± 0.01 mm NO 3 - , 0.17 ± 0.01 mm PO 4 - 3 and pH 7.88. At point 2, water of 35 ± 1 psu had concentrations of 1.13 ± 0.05 mm NH 4 + , 3.73 ± 0.01 mm NO 3 - , 0.52 ± 0.01 mm PO 4 - 3 and pH 8.55. Chlorophyll a, phycobiliproteins, carotenoids, mycosporins, polyphenolics and antioxidant enzymes (catalase, superoxide dismutase and guaiacol peroxidase) were evaluated. The present study demonstrates that ultraviolet radiation triggers antioxidant activity in the A. spicifera. However, such activation resulted in greater responses in samples of the point 1, with lower salinity and highest concentration of nutrients.

Asunto(s)

RESUMEN

This study aimed at assessing the cell cycle, and anatomical and biochemical changes that the embryonic axis of Araucaria angustifolia undergoes during development, focusing on the maturation stage. During all development, cells exhibited intense metabolic activity with an abundance of mitochondria, lipid bodies, and vacuolated cells. The continued accumulation of starch and protein was observed by LM and TEM and indicated by spectra of FTIR. Cell differentiation of the procambium was observed with a thickening of the cell wall and the formation of resiniferous ducts. At Stage III and IV, cells exhibited structural changes such as altered or elongated mitochondria and presence of plastoglobules. These results suggest that there is a gradual transition from developmental metabolism to germination metabolism. Such changes can contribute to the rapid germination of seeds right after their dispersion, making it an ecological strategy to reduce post-dispersal exposure to predators and to avoid damage from reduced moisture.

Asunto(s)

RESUMEN

Ocean warming is increasing and scientific predictions suggest a rise of up to 4°C in sea water temperatures. The combination of a polluted and warmer environment may be detrimental for aquatic species, especially for primary producers such as seaweeds. This study investigated the potential for interactive effects of an increased seawater temperature in a copper-rich environment on the photosynthetic pigments and metabolic compounds of the red seaweed Gelidium floridanum. Seaweed samples were cultivated in a factorial design with temperature (24°C and 30°C), copper (0 and 3 µM), and time (7 and 14 d). The exposure of G. floridanum to copper and 30°C for 7 d resulted in a lower concentration of chlorophyll a, smaller phycobiliprotein rods and lower concentration of soluble sugars. After 14 d of cultivation, a higher concentration of chlorophyll a and soluble sugars could be observed on seaweeds cultivated under 30°C. The accumulation of carotenoids and the release of phenolic compounds indicated specific protective mechanisms against temperature and copper, respectively. Overall, seaweeds grew less when exposed to copper 3 µM at 30°C.

Asunto(s)

RESUMEN

Hemocyte populations of the pearl oyster Pteria hirundo were characterized at morphological, ultrastructural and functional levels. Three main hemocyte populations were identified: hyalinocytes, granulocytes and blast-like cells. Hyalinocytes were the most abundant population (88.2%) characterized by the presence of few or no granules in the cytoplasm and composed by two subpopulations, large and small hyalinocytes. Comparatively, granulocytes represented 2.2% of the hemocyte population and were characterized by the presence of numerous large electron-lucid granules in the cytoplasm. Finally, the blast-like cells (9.5%) were the smallest hemocytes, showing spherical shape and a high nucleus/cytoplasm ratio. Hemocytes exhibited a significant phagocytic capacity for inert particles (38.5%) and showed to be able to produce microbicidal molecules, such as reactive oxygen species (ROS) (ex vivo assays). The immune role of hemocytes was further investigated in the P. hirundo defense against the Gram-negative Vibrio alginolyticus. A significant decrease in the total number of hemocytes was observed at 24 h following injection of V. alginolyticus or sterile seawater (injury control) when compared to naïve (unchallenged) animals, indicating the migration of circulating hemocytes to the sites of infection and tissue damage. Bacterial agglutination was only observed against Gram-negative bacteria (Vibrio) but not against to marine Gram-positive-bacteria. Besides, an increase in the agglutination titer was observed against V. alginolyticus only in animals previously infected with this same bacterial strain. These results suggest that agglutinins or lectin-like molecules may have been produced in response to this particular microorganism promoting a specific recognition. The ultrastructural and functional characterization of P. hirundo hemocytes constitutes a new important piece of the molluscan immunity puzzle that can also contribute for the improvement of bivalve production sustainability.

Asunto(s)

RESUMEN

Phenanthnere (PHE) is a polycyclic aromatic hydrocarbon continuously discarded in the marine environment and bioavailable to many aquatic species. Although studies about PHE toxicity have been documented for adult oysters, the effects on early developmental stages are poorly characterized in bivalves. In this study, the effects of PHE (0.02 and 2.0µg.L-1) were evaluated on the embryogenesis and larval development of Crassostrea gigas. Toxicity bioassays, growth and deformities assessment, analysis of shell calcium abundance and transcript levels of genes related to xenobiotic biotransformation (CYP2AU2, CYP30C1), immune system (Cg-Tal) and tissue growth and shell formation (Ferritin, Insulin-like, Cg-Try, Calmodulin and Nacrein) were assayed in D-shape larvae after 24h of PHE exposure. At the highest concentration (2.0µg.L-1), PHE decreased the frequency of normal development (19.7±2.9%) and shell size (53.5±2.8mm). Developmental deformities were mostly related to abnormal mantle and shell formation. Lower calcium levels in oyster shells exposed to PHE 2.0µg.L-1 were observed, suggesting effects on shell structure. At this same PHE concentration, CYP30C1, Cg-Tal, Cg-Tyr, Calmodulin were upregulated and CYP2AU2, Ferritin, Nacrein, and Insulin-Like were downregulated compared to control larvae. At the lowest PHE concentration (0.02µg.L-1), it was observed a minor decrease in normal larval development (89,6±6%) and the remaining parameters were not affected. This is the first study to provide evidences that exposure to PHE can affect early oyster development at the molecular and morphological levels, possibly threatening this bivalve species.

Asunto(s)

RESUMEN

Sargassum cymosum was exposed to cadmium (Cd) to determine any physiological and ultrastructural effects. To accomplish this, S. cymosum samples were cultivated under photosynthetic active radiation (PAR) and Cd (0, 0.1, 0.2, 0.4 and 0.8 mg L-1) during 7 and 14 days in laboratory-controlled conditions (0 mg L-1 Cd at both exposure times as control). Seaweeds had high retention capacity (over 90 %) for both exposure times. Growth rates showed significant increases by 14 days, especially for 0.1 and 0.4 mg L-1 Cd. Photosynthetic parameters were unaffected by Cd treatments. Chlorophyll contents were present in higher concentrations for all Cd treatments compared to respective control. Carotenoid profile showed significant differences in total composition and proportion of fucoxanthin and ß-carotene, and no lutein was detected at 14 days. Phenolic and flavonoid compounds showed major accumulation at 14 days. Transmission electron microscopy (TEM) analyses presented major alterations in Cd-treated samples, when compared with respective control, in particular disorganization of cell wall fibrils. When compared to respective control samples, multivariate analyses showed disparate and complex interactions among metabolites in Cd-exposed seaweeds, giving evidence of physiological defence response. Thus, it can be concluded that Cd is a stressor for S. cymosum, resulting in physiological and structural alterations related to defence mechanisms against oxidative stress and toxicological effects resulting from long-term metal exposure. However, in the present paper, some observed changes also appear to result from acclimation mechanisms under lower concentration of Cd relative to the tolerance of S. cymosum to experimental conditions.

Asunto(s)

RESUMEN

Fossil fuels, e.g. gasoline and diesel oil, account for substantial share of the pollution that affects marine ecosystems. Environmental metabolomics is an emerging field that may help unravel the effect of these xenobiotics on seaweeds and provide methodologies for biomonitoring coastal ecosystems. In the present study, FTIR and multivariate analysis were used to discriminate metabolic profiles of Ulva lactuca after in vitro exposure to diesel oil and gasoline, in combinations of concentrations (0.001%, 0.01%, 0.1%, and 1.0% - v/v) and times of exposure (30min, 1h, 12h, and 24h). PCA and HCA performed on entire mid-infrared spectral window were able to discriminate diesel oil-exposed thalli from the gasoline-exposed ones. HCA performed on spectral window related to the protein absorbance (1700-1500cm-1) enabled the best discrimination between gasoline-exposed samples regarding the time of exposure, and between diesel oil-exposed samples according to the concentration. The results indicate that the combination of FTIR with multivariate analysis is a simple and efficient methodology for metabolic profiling with potential use for biomonitoring strategies.

Asunto(s)

RESUMEN

Halodule wrightii is an ecologically important seagrass; however, little is known about the adaptation of this species in the context of environmental change, particularly changes arising from alterations in salinity of coastal ecosystems. This study aimed to determine the effects of different salinities on growth, morphology, leaf ultrastructure, and cell viability of H. wrightii. To accomplish this, plants were cultivated for 21 days in salinities of 25, 35, and 45. More hydropotens were observed in samples exposed to salinity of 45 with increased invagination of the plasma membrane and cell wall. These invaginations were also observed in other epidermal cells of the leaf blade. In particular, a significant retraction of plasma membrane was seen in samples exposed to salinity of 45, with possible deposition of compounds between the membrane and cell wall. Osmotic stress in samples exposed to salinity of 45 affected the chloroplasts through an increase in plastoglobules and thylakoids by granum in the epidermal chloroplasts of the leaf and decrease in the number of chloroplasts. Overall, this study showed that H. wrightii can survive within salinities that range between 25 and 45 without changing growth rate. However, the plant did have higher cell viability at salinity of 35. Salt stress in mesocosms, at both salinity of 25 and 45, decreased cell viability in this species. H . wrightii had greater changes in salinity of 45; this showed that the species is more tolerant of salinities below this value.

Asunto(s)

RESUMEN

Refined fuels have considerable share of pollution of marine ecosystems. Gasoline is one of the most consumed fuel worldwide, but its effects on marine benthic primary producers are poorly investigated. In this study, Ulva lactuca was chosen as a biological model due to its cosmopolitan nature and tolerance to high levels and wide range of xenobiotics and our goal was to evaluate the effects of gasoline on ultrastructure and metabolism of that seaweed. The experimental design consisted of in vitro exposure of U. lactuca to four concentrations of gasoline (0.001%, 0.01%, 0.1%, and 1.0%, v/v) over 30 min, 1 h, 12 h, and 24 h, followed by cytochemical, SEM, and biochemical analysis. Increase in the number of cytoplasmic granules, loss of cell turgor, cytoplasmic shrinkage, and alterations in the mucilage were some of the ultrastructural alterations observed in thalli exposed to gasoline. Decrease in carotenoid and polyphenol contents, as well as increase of soluble sugars and starch contents were associated with the time of exposure to the xenobiotic. In combination, the results revealed important morphological and biochemical alterations in the phenotype of U. lactuca upon acute exposure to gasoline. This seaweed contain certain metabolites assigned as candidates to biomarkers of the environmental stress investigated and it is thought to be a promise species for usage in coastal ecosystems perturbation monitoring system. In addition, the findings suggest that U. lactuca is able to metabolize gasoline hydrocarbons and use them as energy source, acting as bioremediator of marine waters contaminated by petroleum derivatives.

Asunto(s)

RESUMEN

AIM: Triterpenes and their derivatives influence on carbohydrate metabolism. In vivo and in vitro treatment investigated the effect of the natural triterpene fern-9(11)-ene-2α,3ß-diol (1), isolated from Croton heterodoxus, and a derivative triterpene (2) on glucose homeostasis. MAIN METHODS: The antidiabetic effect of the crude extract from C. heterodoxus leaves, the natural triterpene (1) as well as the derivative triterpene (2) were assayed on glucose tolerance. The effect and the mechanism of action on in vivo treatment with triterpene 2 on glycaemia and insulin secretion were studied. In addition, in vitro studies investigated the mechanism of triterpene 2 on glucose uptake and calcium influx on insulin secretion in pancreatic islets. KEY FINDINGS: The results show the extract slightly reduced the glycaemia when compared with hyperglycemic group. However, the presence of the substituent electron-withdrawing 4-nitrobenzoyl group in the A-ring of triterpene 2 powered the serum glucose lowering compared to triterpene 1. In addition, in vivo treatment with triterpene 2 significantly increased the insulin secretion induced by glucose and stimulated the glucose uptake and calcium influx in pancreatic islet. The effect of triterpene on calcium influx was completely inhibited by diazoxide, nifedipine and stearoylcarnitine treatment. SIGNIFICANCE: The stimulatory effect of triterpene 2 on glucose uptake, calcium influx, regulation of potassium (K(+)-ATP) and calcium (L-VDCCs) channels activity as well as the pathway of PKC highlights the mechanism of action of the compound in pancreatic islets on insulin secretion and glucose homeostasis. In addition, this compound did not induce toxicity in this experimental condition.

Asunto(s)

RESUMEN

Chromium III oxide (Cr2O3) nanoparticles (NPs) are used in pigments for ceramics, dyes, paints and cosmetics. However, few studies addressing the toxic potential of these NPs have been reported in the literature. Thus, this research aimed to evaluate the acute and chronic effects of Cr2O3 NPs through acute toxicity tests with Daphnia magna and Aliivibrio fischeri and chronic toxicity tests with Daphnia magna. Cr2O3 NPs were synthesized by the sol-gel method and characterized through TEM, X-Ray diffraction (XRD), zeta potential (ZP) and surface area analysis. In the acute toxicity tests the EC(50,48h) value obtained with D. magna was 6.79 mg L(-1) and for A. fischeri the EC(50,15min) value was 16.10 mg L(-1) and the EC(50,30min) value was 12.91 mg L(-1). Regarding the chronic toxicity tests with D. magna, effects on longevity (OEC=1.00 mg L(-1)), reproduction (OEC=1.00 mg L(-1)) and growth (OEC=0.50 mg L(-1)) were observed. On the SEM and TEM images, ultrastructural alterations in the organelles of exposed organisms were also observed. Thus, toxicological studies with NPs are of great importance in order to reduce the risk of environmental contamination.

Asunto(s)

RESUMEN

This data article is referred to the research article entitled The role of ascorbate peroxidase, guaiacol peroxidase, and polysaccharides in cassava (Manihot esculenta Crantz) roots under postharvest physiological deterioration by Uarrota et al. (2015). Food Chemistry 197, Part A, 737-746. The stress duo to PPD of cassava roots leads to the formation of ROS which are extremely harmful and accelerates cassava spoiling. To prevent or alleviate injuries from ROS, plants have evolved antioxidant systems that include non-enzymatic and enzymatic defence systems such as ascorbate peroxidase, guaiacol peroxidase and polysaccharides. In this data article can be found a dataset called "newdata", in RData format, with 60 observations and 06 variables. The first 02 variables (Samples and Cultivars) and the last 04, spectrophotometric data of ascorbate peroxidase, guaiacol peroxidase, tocopherol, total proteins and arcsined data of cassava PPD scoring. For further interpretation and analysis in R software, a report is also provided. Means of all variables and standard deviations are also provided in the Supplementary tables ("data.long3.RData, data.long4.RData and meansEnzymes.RData"), raw data of PPD scoring without transformation (PPDmeans.RData) and days of storage (days.RData) are also provided for data analysis reproducibility in R software.

RESUMEN

Seasonal changes in the biochemistry and photophysiology of the brown macroalga Cystoseira tamariscifolia was analyzed in southern Spain. Total carbon and nitrogen contents, phenolic compounds, antioxidant and photosynthetic activities were seasonally determined over two years. Carbon, nitrogen and photoprotective phenolic contents were higher in winter and spring than in summer and autumn. Antioxidant levels were highest in spring and we found a positive correlation between phenolic content and antioxidant activity (EC50). Photosynthetic capacity (ETRmax) and photosynthetic efficiency (αETR) were also highest in spring, and there was a positive correlation between ETRmax and the amount of phenols present. Increased irradiance in spring enhanced algal productivity, antioxidant activity and the production of photoprotective compounds but in summer nutrient depletion due to thermal stratification of coastal waters reduced photosynthetic activity and the photoprotective capacity of C. tamariscifolia. Electron microscopy showed that phenols occurred in the cytoplasm of cortical cells inside physodes. Spring would be the best period to harvest C. tamariscifolia to extract photoprotectors and antioxidants for potential commercial uses, although the environmental impacts would need to be carefully assessed.

Asunto(s)

RESUMEN

The effects of the heavy metals copper (Cu) and lead (Pb) on Sargassum cymosum were evaluated by determining uptake capacity, growth rates, photosynthetic efficiency, contents of photosynthetic pigments and phenolic compounds, 2,2-diphenyl-1-picrylhydrazyl radical-scavenging capacity, and morphological and cellular changes. S. cymosum was cultivated with Cu and Pb separately and combined at concentrations of 10, 25, and 50 µM for 7 days in laboratory-controlled conditions. Seaweeds under Cu treatment showed the highest biosorption capacity, and growth rates were significantly reduced compared to the control. The photosynthesis/irradiance curves showed alterations in kinetic patterns in the metal-treated samples. Specifically, Cu treatment alone inhibited electron transport rate (ETR) response, while Pb alone induced it. However, samples treated with both Cu and Pb (Cu + Pb) showed inhibition in ETR. The total amount of pigments increased relative to control. Light microscopy showed an increase in phenolic compounds, with physodes migrating towards cortical cells. Scanning electronic microscopy revealed alterations in the typical rough surface of thallus, when compared with control, especially for Pb treatments. Based on these results, it could be concluded that Cu and Pb are stress factors for S. cymosum, promoting alterations in seaweed metabolism and stimulating protective mechanisms against oxidative stress. However, the high bioaccumulation capacity of both heavy metals indicates a possible application for S. cymosum as a biosorbent agent for contaminated wastewater when metals are in low concentrations.

Asunto(s)

RESUMEN

Studies have clearly demonstrated the damaging effects of UV-B exposure on macroalgae, but few have reported the impact of UV-B on spore germination and development at juvenile stages. Therefore, this work aimed to analyze the effects of UV-B radiation on germlings of Nemalion helminthoides at the tetrasporophytic phase. To accomplish this, germlings of N. helminthoides were cultivated in the laboratory and separated into two groups. The control group was exposed onlyto photosynthetic radiation, while the treatment group was exposed to photosynthetic radiation + UV-B for 2 hours during a period of 12 days. Control germlings showed increasing cellular proliferation and accumulation of reserve substances, as well as intense ramification in the last observed stages between 9 days and 12 days of development. Moreover, the chloroplasts presented a typical globular pyrenoid, profusely traversed by thylakoid membranes. Treated germlings, by contrast, showed intracellular damage, such as cell wall thickness, loss of chloroplast organization, changes in mitochondrial cristae, and increasing atrophy of the Golgi bodies. Additionally, changes in developmental patterns were observed, including loss of polarity in the first divisions of carpospores and abnormal stem ramification. The quantification of autofluorescence data coincided with the ultrastructural changes observed in the chloroplasts of cells exposed to UV-B. It can be concluded that exposure to radiation changed the developmental pattern and morphology of the germlings of N. helminthoides.