A polyphasic taxonomy of Daldinia (Xylariaceae)

For a monograph based on a polythetic concept, several thousands of herbarium specimens, and several hundreds of freshly collected and cultured specimens of Daldinia and allied Xylariaceae, originating from around the world, were studied for morphological traits, including by SEM, and chemically by HPLC profiles using UV-visible and mass spectrometric detection. Emphasis was given to tropical material, and importantly, ancient specimens, including as many types as possible, were tracked and studied to review earlier taxonomic concepts. An epitype of D. eschscholtzii was selected as representative of the morphochemotype that is most widely distributed in the tropics. Six new species of Daldinia from the tropics and the southern Hemisphere are described. Daldinia asphalatum is resurrected, and D. cudonia is regarded as its synonym. In addition, the following binomials are epi-, iso-, neo- and/or lectotypified: Daldinia asphalatum, D. caldariorum, D. clavata, D. cuprea, D. durissima, D. eschscholtzii, D. grandis, D. loculata, and D. vernicosa. Annellosporium and Versiomyces are regarded as synonyms of Daldinia. Many new synonymies in Daldinia are proposed, and some previously published names are rejected. In total, 47 taxa in Daldinia are recognised and a key is provided. Their biogeography, chorology, and ecology, as well as the importance of their secondary metabolites, are also discussed. The previous definition of the genus is emended. The species concept is based mainly on morphological and other phenotype-derived characters because, despite diligent search, no molecular data or cultures of several of the accepted species could be obtained. Daldinia is segregated into five major groups, based on phenotypic characteristics. Some unnamed but aberrant specimens were not found in good condition and are therefore not formally described as new species. However, they are illustrated in detail in a hope that this will facilitate the discovery of fresh material in future. A preliminary molecular phylogeny based on 5.8S/ITS nrDNA including numerous representatives of all hitherto described taxa for which cultures are extant, was found basically in agreement with the above mentioned segregation of the genus, based on morphological and chemotaxonomic evidence. In the rDNA based phylogenetic tree, Daldinia appears clearly distinct from members of the genera Annulohypoxylon and Hypoxylon; nevertheless, representatives of small genera of predominantly tropical origin (Entonaema, Phylacia, Ruwenzoria, Rhopalostroma, Thamnomyces) appear to have evolved from daldinioid ancestors and are nested inside the Daldinia clade. Interestingly, these findings correlate with chemotaxonomic characters to a great extent, especially regarding the distribution of marker metabolites in their mycelial cultures. Hence, the current study revealed for the first time that fungal secondary metabolite profiles can have taxonomic value beyond the species rank and even coincide with phylogenetic data.

Taxonomic novelties:

Daldinia andina sp. nov., D. australis sp. nov., D. hausknechtii sp. nov., D. rehmii sp. nov., D. starbaeckii sp. nov., D. theissenii sp. nov., D. cahuchosa comb. nov., D. nemorosa comb. nov.Key words: Ascomycota, biodiversity, chemotaxonomy, systematics, Xylariales     

In vitro evidence that leptin suppresses melatonin secretion during long days and stimulates its secretion during short days in seasonal breeding ewes

Recent observations in seasonal-breeding mammals indicate that the hypothalamus is programmed to become leptin resistant during long days (LD) and leptin sensitive during short days (SD). These observations support the possibility that photoperiod mediates at least part of its effects on melatonin secretion through changes in leptin sensitivity. Herein we examined the interaction of season and recombinant ovine leptin (oleptin) on melatonin secretion by pineal explants in short-term culture. Glands were collected after sunset from eight ewes during LD (March, April, May, June) and from an additional eight ewes during SD (September, October, November, December). Glands were transected saggitally and coronally into quarters, with each equilibrated in 2.5ml of DMEM for 120min, followed by a 3h incubation in medium containing either 0 or 50ng/ml of oleptin. Treatment with oleptin reduced (P<0.001) melatonin secretion compared to controls during LD by approximately 22% at 2, 2.5 and 3h of culture. However, in cultures from glands collected during SD, oleptin stimulated (P<0.078) melatonin secretion approximately 50% compared to control. These effects were consistent throughout each respective season. We conclude that the secretion of melatonin from the ovine pineal gland is negatively responsive to leptin during LD, whereas leptin may stimulate melatonin secretion during SD.     

Motility parameters of perch spermatozoa (Perca fluviatilis L.) during short-term storage with antioxidants addition

In a natural environment, seminal plasma provides spermatozoa with protection against reactive oxygen species. Storing semen in cooling conditions requires diluting it with various buffer solutions. Therefore, the protective role of seminal plasma is not sufficient enough. Semen obtained from five male specimens was diluted with the Kobayashi buffer solution at a 1:9 ratio. To determine the influence of antioxidants on semen storage, a buffer solution was used, as before, with the addition of 1 % albumin, 1 mM vitamin C, 1.5 mg ml^?1 vitamin E, 5 mM sodium citrate, 5 mM glutathione and 5 mM cysteine. After the preparation of such tests, the parameters of spermatozoa motility were measured every 3–5 days, using the CASA system (Image House CRISMAS Company Ltd.). Among all used antioxidants, the best effects were observed after the addition of glutathione to semen. After 17 days of storage, the percentage of motile spermatozoa in the samples preserved with glutathione addition was 57 %, while without antioxidant addition, it was 44 %. Furthermore, the addition of cysteine and albumin also resulted in the lengthening of the life span of perch sperm cells. The presence of the remaining antioxidants (vitamins C and E, and sodium citrate) did not have any positive influence on spermatozoa viability, and in these samples, no motile spermatozoa were observed after 12 days of storage. Our data show that dilution of perch sperm with buffered solution might be a promising method for short-term storage.     

Endogenous Action of Cysteine Endopeptidase and Three Carboxypeptidases on Triticale Prolamins

Quantitative and qualitative changes occurring in the prolamin fraction in the starchy endosperm of triticale grains were analyzed by SDS‐PAGE on consecutive days of germination. The most intensive hydrolysis of prolamins was observed after the second day of the process. The high molecular weight fractions of prolamins were degraded with the highest rate. Endopeptidase EP8 was capable of hydrolyzing all fractions of prolamins isolated from dry triticale grains, but the high molecular weight fractions were the most rapidly degraded by the enzyme. Carboxypeptidases I, II, and III isolated from triticale grains hydrolyzed prolamins proteolytically modified by endopeptidase EP8, whereas intact prolamins were degraded slightly. Differences in the activity of the studied carboxypeptidases against crude prolamins indicate that carboxypeptidase II may be involved in the initiation of the hydrolysis process and, together with carboxypeptidases I and III, participates in the later stages of degradation of prolamins to amino acids. Experiments with exogenous GA₃ demonstrated that the synthesis of EP8 is induced by this hormone and takes place in the aleurone layer. Mass spectrometry analysis showed the enzyme to be a homologue of barley endopeptidase EP‐A. Both enzymes belong to the cysteine class endopeptidases.     

Riboflavin content in the coelomocytes of contrasting earthworm species is differentially affected by edaphic variables including organic matter and metal content

The riboflavin content in extruded coelomocyte lysates derived from Dendrodrilus rubidus may serve as a sensitive bioindicator of soil metal pollution: the vitamin (B2) content has previously been found to be high in worms from unpolluted soil but low in worms inhabiting Zn/Pb mine soils, aerially deposited Ni-contaminated soil, and in worms experimentally transferred from clean soil to the metalliferous field soils. The aim of the present work was to extend these observations by comparing the number and riboflavin composition of coelomocytes retrieved from three lumbricid species (Allolobophora chlorotica, Dendrobaena veneta, Eisenia andrei) after 4-week exposures to an unpolluted commercial soil, two geochemically contrasting unpolluted field soils, and two different Zn/Pb/Cd-polluted soils from the Bukowno district in South Poland. Whilst eco-physiologically contrasting, these three earthworm species share the trait of possessing relatively high numbers of eleocytes, a category of immune-competent coelomocyte rich in autofluorescent riboflavin. Spectroflurometric analysis indicated that coelomocyte riboflavin content in worms maintained in strongly metalliferous soils or in unpolluted sandy-clay and loamy-sand soils was increased in coleomocytes from epigeic D. veneta and E. andrei species, whilst was decreased in endogeic A. chlorotica. In conclusion, the riboflavin content of earthworm coelomocytes is affected in species-specific ways by edaphic variables, including organic matter and metal pollution.     

A novel cytometric approach to study intestinal mucosa rebuilding in weaned pigs fed with dietary nucleotides

In the weaning period, transition from sow's milk to the post-weaning diet causes the withdrawal of important nutrients as milk nucleotides, which are known to be determinant for the development of the gastrointestinal tract and immune function. The role of dietary nucleotides in the rebuilding of gut epithelium remains unclear. The aim of the study was to evaluate using appropriate markers the rate of mitosis (Ki67) in the crypt epithelial cell, and the rate of apoptosis (active caspase 3), autophagy (MAP I LC3) and DNA damage (p53) in the crypt and villi epithelial cells of the small intestine of weaned pigs fed diets supplemented without/with nucleotides. An in-tissue cytometry method, based on confocal imaging and automated quantitative analysis was implemented. The studies allowed us to understand molecular bases of animal performance which could not be accessed by a routine histometric approach. Namely, the dietary nucleotides provided more uniform small intestine epithelium with considerably less animal-to-animal variation in respect to mitosis (SEM = 1.02 in control vs. 0.62 in supplemented group), autophagy (SEM = 1.22 vs. 0.99) and expression of p53 protein (SEM = 0.72 vs. 0.28). A significant increase in ratio of apoptosis and autophagy, and significantly lower p53 expression was found in the nucleotide-supplemented pigs as compared to control. The mitosis/apoptosis index was lower in the nucleotide-supplemented group suggesting slower rebuilding of gut epithelium in these pigs as compared to the control, respectively 0.454 to 0.191. Finally, in the supplemented group a drop in p53 expression was observed, however, it remains uncertain whether the reduction in DNA damage index is due to the supplementation with nucleotides utilized as a source for repair processes or due to the reduced DNA alterations.     

Electromagnetic energy sources in surgery

The biophysics, mechanism of actions, applications, benefits and complications of electromagnetic (EM) energy-based surgical instruments, and their current use are reviewed. Understanding the mechanism of action, tissue effects, and appropriate applications of EM devices is critical to achieving an optimal surgical outcome. Although a more diverse range of EM devices are used in human medicine, current use in veterinary medicine is limited to conventional electrosurgery and CO(2) lasers.     

A Comparison of Ultrastructural Changes of Barley Cells Infected with Mild and Aggressive Isolates of Barley stripe mosaic virus

Journal of Plant Diseases and Protection - Electron microscopy studies were carried out to investigate the association of visible disease symptoms with ultrastructural changes in barley plants...