Multi-proxy analysis of waterlogged preserved Late Neolithic canine excrements

Vegetation History and Archaeobotany - Multi-proxy analysis of the coprolites which were found during excavations at two Late Neolithic (fourth millennium bc) pile-dwelling sites (Črnelnik and...     

Morphological and immunohistochemical study of the midgut and fat body of Spodoptera frugiperda (J.E. Smith) (Lepidoptera: noctuidae) treated with essential oils of the genus Piper

ABSTRACT

Essential oils are a promising alternative to insecticides. We investigated the LD₅₀ of oils extracted from Piper corcovadensis, P. marginatum, and P. arboreum after 48 h topical contact with Spodoptera frugiperda larvae using morphometry, histochemistry and immunohistochemistry of the midgut and fat body. Chromatography revealed that E-caryophyllene was the principal compound common to the Piper species. The essential oils of P. corcovadensis, P. marginatum and P. arboreum caused deleterious changes in the midgut of S. frugiperda larvae. P. corcovadensis oil produced the lowest LD₅₀ and significant histopathological alterations including elongation of the columnar cells, formation of cytoplasmic protrusions, reduction in carbohydrate, increased apoptotic index and decreased cell proliferation. P. arboreum oil caused histopathological alterations similar to P. corcovadensis, but caused the highest rate of cell proliferation and increased regenerative cells, which indicated rapid regeneration of the epithelium. Our findings demonstrated the insecticidal potential of P. corcovadensis for control of S. frugiperda owing to the significant damage it inflicted on S. frugiperda midgut.     

Enzymatic activity of L-amino acid oxidase from snake venom Crotalus adamanteus in supercritical CO2

L-amino acid oxidase (L-AAO) from snake venom Crotalus adamanteus was successfully tested as a catalyst in supercritical CO₂ (SC-CO₂). The enzyme activity was measured before and after exposure to supercritical conditions (40°C, 110 bar). It was found that L-AAO activity slightly increased after SC-CO₂ exposure by up to 15%. L-AAO was more stable in supercritical CO₂ than in phosphate buffer under atmospheric pressure, as well as in the enzyme membrane reactor (EMR) experiment. 3,4-Dihydroxyphenyl-L-alanine (L-DOPA) oxidation was performed in a batch reactor made of stainless steel that could withstand the pressures of SC-CO₂, in which L-amino acid oxidase from C. adamanteus was able to catalyze the reaction of oxidative deamination of L-DOPA in SC-CO₂. For the comparison L-DOPA oxidation was performed in the EMR at 40°C and pressure of 2.5 bar. Productivity expressed as mmol-s of converted L-DOPA after 3?h per change of enzyme activity after 3?h was the highest in SC-CO₂ (1.474?mmol?U^?1), where catalase was present, and the lowest in the EMR (0.457?mmol?U^?1).     

The Phosphorylated Pathway of Serine Biosynthesis Is Essential Both for Male Gametophyte and Embryo Development and for Root Growth in Arabidopsis

This study characterizes the phosphorylated pathway of Ser biosynthesis (PPSB) in Arabidopsis thaliana by targeting phosphoserine phosphatase (PSP1), the last enzyme of the pathway. Lack of PSP1 activity delayed embryo development, leading to aborted embryos that could be classified as early curled cotyledons. The embryo-lethal phenotype of psp1 mutants could be complemented with PSP1 cDNA under the control of Pro35S (Pro35S:PSP1). However, this construct, which was poorly expressed in the anther tapetum, did not complement mutant fertility. Microspore development in psp1.1/psp1.1 Pro35S:PSP1 arrested at the polarized stage. The tapetum from these lines displayed delayed and irregular development. The expression of PSP1 in the tapetum at critical stages of microspore development suggests that PSP1 activity in this cell layer is essential in pollen development. In addition to embryo death and male sterility, conditional psp1 mutants displayed a short-root phenotype, which was reverted in the presence of Ser. A metabolomic study demonstrated that the PPSB plays a crucial role in plant metabolism by affecting glycolysis, the tricarboxylic acid cycle, and the biosynthesis of amino acids. We provide evidence of the crucial role of the PPSB in embryo, pollen, and root development and suggest that this pathway is an important link connecting primary metabolism with development.     

Plant communities of the montane mesophilous grasslands (Polygono bistortae–Trisetion flavescentis alliance) in central Europe: Formalized classification and syntaxonomical revision

Abstract

The research conducted here presents a syntaxonomical revision of the montane mesophilous meadows of the Polygono bistortae-Trisetion flavescentis alliance in central Europe – the Slovak part of the western and eastern Carpathians. These typical semi-natural grasslands occur mainly as small islands over the calcareous bedrocks. Associations of this alliance have tight relationships to the Arrhenatherion, Mesobromion and Nardo-Agrostion alliances. Formal definitions based on combination of the species groups were used regarding the diversity and geographical range of the Polygono bistortae-Trisetion flavescentis alliance. Following the formal definitions from the eight associations reported previously for Slovakia, only four of them can be placed within the Polygono bistortae-Trisetion flavescentis: Campanulo glomeratae-Geranietum sylvatici, Geranio sylvatici-Trisetetum, Crepido mollis-Agrostietum capillaries and Geranio-Alchemilletum crinitae. A comparison of traditional and formalized classification, and the advantages/disadvantages of the formalized classification are discussed.     

Hosts and distribution of Viscum album L. ssp. album in Croatia and Slovenia

Abstract

Viscum album L. ssp. album is semi-parasitic on deciduous trees and shrubs. In order to identify hosts and map the distribution of V. album ssp. album in Croatia and Slovenia, field research was carried out, and herbaria were surveyed. In Croatia and Slovenia, V. album ssp. album occurred on 59 taxa. In Croatia, there were 52 hosts (33 autochthonous and 15 allochthonous species, two cultivars and two hybrids). In Slovenia, there were 25 hosts (21 autochthonous and four allochthonous species). There were 18 hosts common to both countries, 34 hosts were found only in Croatia, and seven hosts only in Slovenia. The hosts belonged to 13 families. The majority of these (19 species) belong to the Rosaceae, followed by Salicaceae, Aceraceae, Betulaceae, Fagaceae, Juglandaceae, Tiliaceae, Hippocastanaceae, Ulmaceae, Oleaceae, Fabaceae, Moraceae and Viscaceae. All hosts have been previously recorded in the literature, except Alnus japonica (Thunb.) Steud., Amelanchier lamarckii F.G. Schroed. and Crataegus nigra Waldst. et Kit. The distribution of this mistletoe was scattered, due to the scattered distribution of hosts, local conditions, movement of bird-vectors, etc. A continuous distribution was found only in part of the distribution area of narrow-leaved ash (Fraxinus angustifolia Vahl).     

Leaflet morphometric variation of service tree (Sorbus domestica L.) in the Balkan Peninsula

Abstract

In most European countries, the service tree (Sorbus domestica L.) is a rare and threatened species and its conservation has been recognised as a priority. The aim of this study was to asses its morphologic variation in the western and central part of the Balkan Peninsula and in southern Central Europe. Three populations were analysed: one in Serbia, one in Bosnia and Herzegovina and one in Slovenia. In each population 30 trees were selected, and from each tree 30 leaves were collected for morphometric analysis based on nine leaflet morphological traits. Univariate (ANOVA) and multivariate (MANOVA) analysis of variance were used to estimate the variation within- and between populations and a discriminant analysis was performed to examine the structure of the between-population differences. The values of particular morphological traits found in our study did not differ considerably from the values reported elsewhere. The results revealed significant within- and between population variation. Variation within populations was highly significant for all the scored leaf morphological traits, while variation between populations was significant for all the studied traits except for the leaflet length. The discrimination between the three populations was significant. High percentages of correctly classified samples demonstrate good discriminating employability of the analysed leaf morphological traits and indicate differentiation of the analysed populations.     

New inhibitors of fungal 17β-hydroxysteroid dehydrogenase based on the [1,5]-benzodiazepine scaffold

The synthesis and activity of a new series of non-steroidal inhibitors of 17β-hydroxysteroid dehydrogenase that are based on a 1,5-benzodiazepine scaffold are presented. Their inhibitory potential was screened against 17β-hydroxysteroid dehydrogenase from the fungus Cochliobolus lunatus (17β-HSDcl), a model enzyme of the short-chain dehydrogenase/reductase superfamily. Some of these compounds are potent inhibitors of 17β-HSDcl activity, with IC₅₀ values in the low micromolar range and represent promising lead compounds that should be further developed and investigated as inhibitors of human 17β-HSD isoforms, which are the enzymes associated with the development of many hormone-dependent and neuronal diseases.     

Synthesis of Fluorinated Indoles as RNA Analogues

Nucleoside analogues are chemical means to investigate hydrogen bonds, base stacking, and solvation as the three predominant forces that are responsible for the stability of secondary structure of nucleic acids. To obtain deeper insight into the contributions of these interactions to RNA stability apart from the ones exerted by the predominant nucleosides we decided to synthesize some novel nucleic acid analogues where the nucleobases are replaced by fluoroindoles. Fluorinated indoles can be compared to fluorinated benzimidazoles to determine the role of nitrogen in five membered ring system. The synthesis of fluoroindole ribonucleosides is described here.