RESUMEN
Following the Unification of Italy (1861), when confronted with the underdevelopment problems of the south that had given rise to the so-called "southern question," some Italian anthropologists and psychologists began to study the populations of the south from the psycho-anthropological point of view. These scientists, at times subject to preconceived ideas toward the southerners, conveyed observations and descriptions of the southern character traits that, in general, were considered different, in a negative sense, with respect to those of the northern peoples. To explain such diversity in the "psychological" characteristics between the north and south of the country (presumed cause also of the south's backwardness), various hypotheses were advanced related to the kind of heredity theory adopted, which could be of, more or less, an "innatist" or "transformist" or "environmentalist" kind. The distinction proposed in this article between at least 2 different "hereditarian" theories formulated by the Italian scientists, and the confrontation of these theories with the hypotheses expressed by the "southernist" sociologists, contrary to the idea of "racial varieties" present in the Italian population, allows one to understand in what way and in what sense, at the threshold of the 20th century, there arose the ideology of "Nordicism" and the roots of racism were planted.
Asunto(s)
Antropología/historia , Psicología/historia , Historia del Siglo XIX , Historia del Siglo XX , Humanos , Italia/etnologíaRESUMEN
Opisthobranchs belong to a subclass of highly evolved and specialised marine gastropods that rely on the use of secondary metabolites for their survival. Here we report the full elucidation of the biosynthesis of aromatic metabolites, lignarenones, in one of these gastropods, the cephalaspidean Scaphander lignarius. Feeding experiments with ²H- and ¹³C-labelled precursors revealed a mixed acetate/propionate polyketide pathway primed by benzoic acid. Phenylalanine ammonia lyase (PAL), unprecedented in animals, is central to the synthesis of this aromatic precursor by oxidative deamination of L-phenylalanine to cinnamic acid. Lignarenones are synthesised in the cytoplasm of specialised eukaryotic cells named Blochmann's glands, which are distributed in biosynthetic tissue localised in the vulnerable mantle of the mollusc. This result supports the hypothesis that this lineage of gastropods has acquired the genetic information to produce the chemical substances that they use for their survival.
Asunto(s)
Citoplasma/metabolismo , Células Eucariotas/metabolismo , Gastrópodos/metabolismo , Fenilanina Amoníaco-Liasa/metabolismo , Policétidos/metabolismo , Animales , Organismos Acuáticos , Ácido Benzoico/metabolismo , Isótopos de Carbono , Cinamatos/metabolismo , Deuterio , Espectroscopía de Resonancia Magnética , Fenilalanina/metabolismo , Polienos/metabolismo , Propionatos/metabolismoRESUMEN
This first chemical study of the sacoglossan mollusk Thuridilla splendens from Mooloolaba, South East Queensland, has resulted in the isolation of three new metabolites, thuridillins D-F (1-3), and one known metabolite, thuridillin A (4). Thuridillin D (1) was isolated by conventional flash chromatography on silica gel, while a mixture of thuridillins E (2) and F (3) was obtained by PTLC on AgNO(3)-impregnated silica gel. Thuridillins D-F were determined to be structurally related to thuridillin B (5); 1 possessed a hydroxy group at C-11, and 2 and 3 were Δ(10,11)- and Δ(11,12)-isomers, respectively. HSQC-HECADE NMR data, together with conformational analysis, NOESY experiments, and (1)H-(1)H coupling studies enabled assignment of the individual relative configurations of the epoxylactone, the 2,5-diacetoxy-2,5-dihydrofuran, and cyclohexyl moieties within thuridillin D (1).
Asunto(s)
Diterpenos/aislamiento & purificación , Moluscos/química , Animales , Australia , Diterpenos/química , Compuestos Epoxi/química , Lactonas/química , Espectroscopía de Resonancia Magnética , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular/métodosRESUMEN
The first chemical study of the Indo-Pacific dorid nudibranch Aldisa andersoni resulted in the isolation of five chlorinated phenyl-pyrrolyloxazoles belonging to the phorbazole series. Two new molecules, 9-chloro-phorbazole D and N1-methyl-phorbazole A, co-occurring with known phorbazoles A, B and D, have been characterized. Phorbazoles were found to be present mainly in the external part of the mollusc. The structures of the new compounds were determined by interpretation of spectroscopic data, mainly NMR and mass spectrometry and by comparison with the literature data. Evaluation of feeding-deterrence activity as well as in vitro growth inhibitory properties in human cancer cells was also carried out.
Asunto(s)
Gastrópodos/química , Oxazoles/aislamiento & purificación , Animales , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Antineoplásicos/farmacología , Línea Celular Tumoral , Humanos , Océano Índico , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Oxazoles/química , Oxazoles/farmacología , Relación Estructura-ActividadRESUMEN
Four diterpenes, tritoniopsins A-D (1-4), have been isolated from the South China Sea nudibranch Tritoniopsis elegans and its prey, the soft coral Cladiella krempfi. They display an unprecedented pyran ring in the cladiellane framework, thus representing a novel cladiellane-based diterpene family. Their structures have been mainly characterized by NMR and mass spectrometric techniques, whereas the relative configuration of compound 1 was secured by X-ray analysis. Antiproliferative assays on tumor and nontumor cell lines have been carried out for the main metabolite, tritoniopsin B (2).
Asunto(s)
Antozoos/química , Antineoplásicos/aislamiento & purificación , Diterpenos/aislamiento & purificación , Gastrópodos/química , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Cristalografía por Rayos X , Diterpenos/química , Ensayos de Selección de Medicamentos Antitumorales , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Océanos y MaresRESUMEN
The Mediterranean Sea is losing its biological distinctiveness, and the same phenomenon is occurring in other seas. It gives urgency to a better understanding of the factors that affect marine biological invasions. A chemoecological approach is proposed here to define biotic conditions that promote biological invasions in terms of enemy escape and resource opportunities. Research has focused on the secondary metabolite composition of three exotic sea slugs found in Greece that have most probably entered the Mediterranean basin by Lessepsian migration, an exchange that contributes significantly to Mediterranean biodiversity. We have found toxic compounds with significant activity as feeding deterrents both in the cephalaspidean Haminoea cyanomarginata and in the nudibranch Melibe viridis. These findings led us to propose aposematism in the former and dietary autonomy in producing defensive metabolites in the latter case, as predisposing factors to the migration. In the third mollusk investigated, the anaspidean Syphonota geographica, the topic of marine invasions has been approached through a study of its feeding biology. The identification of the same compounds from both the viscera of each individual, separately analyzed, and their food, the seagrass Halophila stipulacea, implies a dietary dependency. The survival of S. geographica in the Mediterranean seems to be related to the presence of H. stipulacea. The initial invasion of this exotic pest would seem to have paved the way for the subsequent invasion of a trophic specialist that takes advantage of niche opportunities.
Asunto(s)
Migración Animal , Ecología , Gastrópodos/fisiología , Migración Animal/efectos de los fármacos , Animales , Sistema Digestivo/efectos de los fármacos , Conducta Alimentaria/efectos de los fármacos , Gastrópodos/efectos de los fármacos , Grecia , Extractos Vegetales/química , Extractos Vegetales/farmacología , Pruebas de ToxicidadRESUMEN
A novel bisabolene sesquiterpene dimer named trans-dimer D (1) and its diastereoisomer trans-dimer C (2) reported in our previous work have been isolated as an inseparable mixture in a ratio of 1.5:1 from the South China Sea sponge Axinyssa variabilis. The structure of 1 was determined on the basis of extensive spectroscopic analysis and by comparison of its NMR spectral data with those of structurally related compounds. Compound 1 represents the fourth example of a sesquiterpene dimer with a bis-bisabolene skeleton.
Asunto(s)
Poríferos/química , Sesquiterpenos/química , Sesquiterpenos/aislamiento & purificación , Animales , Estructura Molecular , EstereoisomerismoRESUMEN
The chemical investigation of Azorean nudibranch mollusk Tambja ceutae led us to isolate a new member of the tambjamine family, tambjamine K (1). The bryozoan Bugula dentata, prey of the nudibranch, was also analyzed and found to contain compound 1 in very small amounts together with known blue pigment 2 and tambjamines A (3) and B (4). The structure of tambjamine 1 was elucidated by the interpretation of the spectroscopic data as well as by the comparison with related compounds. Compounds 1 and 2 possess antiproliferative activity, in particular, tambjamine K (1) displayed high cytotoxicity against both tumor and non-tumor mammalian cells.
Asunto(s)
Antineoplásicos/aislamiento & purificación , Moluscos/efectos de los fármacos , Pirroles/aislamiento & purificación , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Línea Celular , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Espectroscopía de Resonancia Magnética , Pirroles/química , Pirroles/farmacologíaRESUMEN
A series of nine casbane diterpenes, compounds 5-13, exhibiting either cis or trans ring junctions were isolated from the Hainan soft coral Sinularia depressa. The structures of this group of compounds, the basic member of which was named depressin (5), were established by detailed spectroscopic analysis. In addition, the absolute configuration of the main metabolite, 10-hydroxydepressin (7), and of its epimer, 1-epi-10-hydroxydepressin (8), was determined by a combination of conformational analysis and the modified Mosher's method. A stereochemical relationship between all isolated molecules was investigated by analyzing their circular dichroism profiles. Antiproliferative and antibacterial activities of the depressins were also evaluated.
Asunto(s)
Antozoos/química , Antineoplásicos/aislamiento & purificación , Diterpenos/aislamiento & purificación , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Dicroismo Circular , Diterpenos/química , Diterpenos/farmacología , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Escherichia coli/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Staphylococcus aureus/efectos de los fármacos , EstereoisomerismoRESUMEN
This article briefly outlines a picture of the activities and research conducted in Italy on the history of psychology during the last 10 years, focusing its attention on institutions, scholars, conferences, archives, journals, and so forth. At the dawn of the 21st century, the tradition of historical-psychological studies that developed in the last quarter of the 20th century has led to a renewed situation in teaching organization and research, with the emergence of several groups, especially at the universities of Rome "Sapienza", Bari, Milan-Bicocca, and Urbino, and of a second generation of young historians increasingly engaged on an international level. After a general survey conducted with historiometric method on the principal areas of research cultivated and on the themes dealt with, we mention a change that has occurred in the historiographical approach, a transition from a historiography addressed prevalently to the "history of ideas" to one that, pursuing the approach of a new and critical "multifactorial" history, proves to be more attentive to the social and institutional history, in correspondence with established international trends.
Asunto(s)
Comparación Transcultural , Historiografía , Psicología/historia , Historia del Siglo XX , Historia del Siglo XXI , Humanos , ItaliaRESUMEN
Polypropionates that incorporate pyrones are a family of polyketides featuring the chemistry of a few marine molluscs capable of phototrophic CO(2) fixation as a result of storing viable symbiotic chloroplasts in their bodies. The role and origin of these molecules is poorly investigated, although the unusual biological activities and chemistry of these natural products have recently received renewed interest. Here, we report the results of in vivo studies on production of gamma-pyrone-containing polypropionates in the Mediterranean mollusc Elysia viridis. Biosynthesis of the metabolites in the sacoglossan is shown to proceed through condensation of eight intact C(3) units by polyketide synthase assembly. LC-MS and NMR spectroscopic studies demonstrate that the process involves a pyrone tetraene (10) as key intermediate, whereas the levels of the final polypropionates (6, 7 and 9) are related to each other and show a significant dependence upon light conditions.
Asunto(s)
Gastrópodos/metabolismo , Gastrópodos/efectos de la radiación , Polímeros/metabolismo , Propionatos/metabolismo , Luz Solar , Animales , Isótopos de Carbono/química , Alimentos , Espectroscopía de Resonancia Magnética , Fotólisis/efectos de la radiación , Polímeros/química , Propionatos/química , Energía Solar , Coloración y EtiquetadoRESUMEN
In recent years, oxylipins (lipoxygenase-derived oxygenated fatty acid products) have been reported in several bloom-forming marine diatoms. Despite increasing attention on the ecophysiological role of these molecules in marine environments, their biosynthesis is largely unknown in these microalgae. Biochemical methods, including tandem mass spectrometry, nuclear magnetic resonance and radioactive probes were used to identify structures, enzymatic activities and growth-dependent modulation of oxylipin biosynthesis in the pennate diatom Pseudo-nitzschia delicatissima. Three major compounds, 15S-hydroxy-(5Z,8Z,11Z,13E,17Z)-eicosapentaenoic acid (15S-HEPE), 15-oxo-5Z,9E,11E,13E-pentadecatetraenoic acid and 13,14-threo-13R-hydroxy-14S,15S-trans-epoxyeicosa-5Z,8Z,11Z,17Z-tetraenoic acid (13,14-HEpETE), were produced by three putative biochemical pathways triggered by eicosapentaenoic acid-dependent 15S lipoxygenase. Oxylipin production increases along the growth curve, with remarkable changes that precede the demise of the culture. At least one of the compounds, namely 15-oxoacid, is formed only in the stationary phase immediately before the collapse of the culture. Synthesis and regulation of phyco-oxylipins seem to correspond to a signaling mechanism that governs adaptation of diatoms along the growth curve until bloom termination. Factors triggering the process are unknown but synthesis of 15-oxoacid, constrained within a time-window of a few days just before the collapse of the culture, implies the involvement of a physiological control not directly dependent on distress or death of diatom cells.
Asunto(s)
Diatomeas/metabolismo , Lipooxigenasa/metabolismo , Oxilipinas/metabolismo , Técnicas de Cultivo de Célula , Diatomeas/crecimiento & desarrollo , Ácido Eicosapentaenoico/metabolismo , Ácidos Grasos Insaturados/biosíntesis , Oxilipinas/química , Oxilipinas/aislamiento & purificaciónRESUMEN
The biosynthesis of lignarenones 1 and 2, the major polyketides of the Mediterranean mollusc Scaphander lignarius is described. The process is primed by benzoic acid and requires acetate and propionate as extender units. The labeling pattern suggests PKS-like synthesis of an unusual E,Z,E-triene chain and origin of the benzoate unit from phenylalanine. 13C-13C NMR COSY has been used to establish the labeling positions due to incorporation of 13C2-acetate.
Asunto(s)
Moluscos/química , Polienos/síntesis química , Animales , Biología Marina , Resonancia Magnética Nuclear Biomolecular , Polienos/química , Sintasas Poliquetidas/metabolismo , EstereoisomerismoRESUMEN
This paper reports the study of terpene biosynthesis in the marine nudibranch Doriopsilla pelseneeri. In vivo feeding experiments with 13C-glucose proved the de novo origin of the terpene metabolites via a mevalonate pathway. Characterization of the stereochemical relationship of the new acetyl pelseneeriols (7 and 8) suggests a two-step mechanism for the sesquiterpene cyclization, leading to a slight refinement of terpene tailoring in this family of marine invertebrates.
Asunto(s)
Moluscos/química , Sesquiterpenos/aislamiento & purificación , Terpenos/aislamiento & purificación , Animales , Biología Marina , Ácido Mevalónico/metabolismo , Estructura Molecular , Océanos y Mares , Sesquiterpenos/química , Terpenos/químicaRESUMEN
Repeated fractionation of the acetylated methanol extract of Prasium majus afforded acetylated derivatives of a new iridoid glycoside hamighriprasin (1), myoporoside (2), beta-D-glycopyranose (3) and saccharose (4). The structures of 1 and 2 were established by interpretation of 1D and 2D NMR data of their corresponding acetylated derivatives and by comparison with the literature.
Asunto(s)
Iridoides/aislamiento & purificación , Lamiaceae/química , Extractos Vegetales/química , Iridoides/química , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Rotación Óptica , Componentes Aéreos de las Plantas/química , Espectrofotometría Infrarroja , Espectrometría de Masas en Tándem , TúnezRESUMEN
Intermediates of the aldehyde biosynthesis in Thalassiosira rotula are investigated. Use of labeled precursors and cell preparations proves production of 2E,4Z-octadienal from 6Z,9Z,12Z-hexadecatrienoic acid (C16:3 omega-4) through the lipoxygenase-dependent intermediate (9S)-9-hydroperoxyhexadeca-6,10,12-trienoic acid. On the contrary, synthesis of 2E,4Z,7Z-decatrienal involves mainly EPA (C20:5 omega-3) by a 11R-lipoxygenase, as suggested by identification of chiral 11R-HEPE (12% e.e.) in the diatom extracts. Consistently with the necessity to have a rapid transport and metabolization of the intermediate hydroperoxides, we show that lipoxygenase and lyase activities are both found in the same subcellular fraction of the microalga.
Asunto(s)
Aldehídos/metabolismo , Diatomeas/química , Diatomeas/enzimología , Ácidos Grasos/metabolismo , Aldehídos/química , Alquenos/química , Ácido Eicosapentaenoico/análogos & derivados , Ácido Eicosapentaenoico/química , Ácido Eicosapentaenoico/metabolismo , Ácidos Grasos/química , Lipooxigenasa/química , Lipooxigenasa/metabolismo , Modelos Biológicos , Conformación Molecular , Resonancia Magnética Nuclear Biomolecular , EstereoisomerismoRESUMEN
Chemical analysis of the secondary metabolite pattern of the sacoglossan mollusc Elysia cf. expansa, collected along South Indian coasts, showed the presence of the typical Caulerpa-derived sesquiterpene caulerpenyne (1) and two new minor co- occurring metabolites, the compounds dihydrocaulerpenyne (4) and expansinol (5). The chemical characterization of these molecules, structurally related to 1, is reported.
Asunto(s)
Gastrópodos/química , Sesquiterpenos/química , Animales , Gastrópodos/metabolismo , India , Indoles , Naftalenos/química , Naftalenos/aislamiento & purificación , Naftalenos/metabolismo , Pirazinas/química , Pirazinas/aislamiento & purificación , Pirazinas/metabolismo , Sesquiterpenos/metabolismoRESUMEN
Diatoms are unicellular plants broadly present in freshwater and marine ecosystems, where they play a primary role in sustaining the marine food chain. In the last 10 years, there has been accumulating evidence that diatoms may have deleterious effects on the hatching success of zooplankton crustaceans such as copepods, thus affecting dynamics of planktonic populations and limiting secondary production. At the molecular level, failure to hatch is ascribed to the presence of a family of inhibitory oxylipins, which we propose to collectively name polyunsaturated short-chain aldehydes (abbreviated here as PUSCAs). Here we describe the origin of PUSCAs produced by the marine diatom Skeletonema costatum via a lipoxygenase-mediated pathways involving non-esterified polyunsaturated fatty acids (PUFA). Experiments with complex lipids proved the pivotal role of chloroplast-derived glycolipids, especially monogalactosyldiacylglycerol (MGDG), in providing hexadecatrienoic acid (C16:3 omega-4), hexadecatetraenoic acid (C16:4 omega-1) and eicosapentaenoic acid (C20:5 omega-3) to the downstream process leading to 2E,4Z-octadienal (C8:2 omega-4), 2E,4Z,7-octatrienal (C8:3 omega-1) and 2E,4Z-heptadienal (C7:2 omega-3), respectively. Under physiological conditions, the hydrolytic process is associated to galactolipid hydrolyzing enzyme capable of removing fatty acids from both sn positions of glycerol.
Asunto(s)
Aldehídos/metabolismo , Diatomeas/metabolismo , Glucolípidos/metabolismo , Fosfolípidos/metabolismo , Aldehídos/química , Células Cultivadas , Cloroplastos/metabolismo , Cromatografía Líquida de Alta Presión/métodos , Diatomeas/citología , Ácido Eicosapentaenoico/biosíntesis , Ácidos Grasos Insaturados/biosíntesis , Ácidos Grasos Insaturados/química , Galactolípidos/análisis , Galactolípidos/metabolismo , Glucolípidos/química , Hidrólisis , Lipooxigenasa/metabolismo , Espectrometría de Masas/métodos , Fosfolípidos/química , Estereoisomerismo , TritioRESUMEN
Two new 19-oxygenated polyhydroxy steroids, 24-methylcholesta-5, 24(28)-diene-3 beta, 7 beta, 19-triol-19-monoacetate (1), 24-methylcholesta-5, 24(28)-diene-3 beta, 7 beta, 19-triol-7 beta, 19-diacetate (3), together with a known steroid, 24-methylcholesta-5, 24(28)-diene-3 beta, 7 beta, 19-triol-7 beta-monoacetate (4), have been isolated from the soft coral Sinularia sp. collected from the South China Sea and characterized through interpretation of spectral data.
Asunto(s)
Antozoos/química , Cnidarios/química , Deshidrocolesteroles/aislamiento & purificación , Esteroides/aislamiento & purificación , Animales , Deshidrocolesteroles/química , Deshidrocolesteroles/farmacología , Hidroxilación , Esteroides/química , Esteroides/farmacologíaRESUMEN
By means of the analysis of three works (Dell'anima de' bruti [Of the soul of beasts], Sofilo Molossio, and Sofilo senza maschera [Sofilo without a mask]) of Alessandro Pascoli (1669-1757), the psysician and philosopher from Perugia, the article reconstructs his fluctuating thought with regard to the problem of sensation in animals, indicated as the problem of the "soul of beasts." Regarding this question, Pascoli oscillates between, on the one hand, the Cartesian theory, which considered animals similar to mechanical automatons, devoid of the capacity to experience sensations (that is say, devoid of "sensitivity"); and, on the other hand, the Church's scholastic-peripatetic doctrine that attributed to animals the capacity to feel, thus affirming the presence in them of a "sensitive soul," considered -as compared with the human one -imperfect, material, and mortal. In expounding the reasons and argumentations of the Cartesians, on the one hand, and of the ecclesiastic teachings, on the other, Pascoli manifests a substantial convergence with the former, but also the need, inasmuch as Catholic professor of medicine at the Sapienza University of Rome, to not deny the possibility of the latter. In this tormented and contorted alternation of opinions, between the thesis of the animal-machine and that of the animal gifted with a sensitive soul, he introduces conceptual elements that, further developed, will end up by conducting to the ideas of "vital property" and of "vital principle" typical of the vitalistic thought of the 18th and 19th centuries.