Physiological and ultrastructural changes in “green islands” on Avena sterilis leaves caused by (8R,16R)-(–)-pyrenophorin

The biochemical and ultrastructural changes in "green islands" (GIs) on detached Avena sterilis leaves caused by the macrodiolide (8R,16R)-(-)-pyrenophorin in the dark were examined. In the absence of light, leaf segments retained their photosynthetic pigments for 96 h after treatment with (8R,16R)-(-)-pyrenophorin (70 muM), whereas in the untreated leaves complete senescence, loss of photosynthetic pigments and cell disorganization were observed 72 h after detachment. Proteolytic enzyme activity in treated tissues with pyrenophorin remained at low levels for 96 h after treatment and protein dissipation was lower in the treated than in the untreated. Although tissues in "GIs" seem macroscopically healthy, electron microscopy observations revealed structurally disorganized cells filled with granular, electron-dense material. Chloroplasts were severely damaged and contained a large number of plastoglobuli. Similar ultrastructural changes were also observed in A. sterilis tissues treated with the phytotoxin under illumination, indicating a mechanism operating both under illumination and in the dark.     

Phase separation and drop size distributions in “homogeneous” Na-alginate/Na-caseinate mixtures

Phase separation and drop size distributions in dilute Na-caseinate/Na-alginate mixtures has been investigated using simultaneously two different measuring techniques: light scattering and image analysis. It has been found that even at very low concentrations of either polymer, where according to literature data the mixture should be homogenous, two phases can be observed. This phase separation was detected by both techniques and in each case, the drop size distributions measured by each of them were in good agreement.     

“Infant Mortality in Armenia 1992–2003”: A comment

The purpose of this comment is to counsel caution in some of the conclusions drawn in an otherwise fine article recently published in Economics and Human Biology on infant mortality in Armenia by Hakobyan, Mkrtchyan and Yepiskoposyan. These relate first, to the reliability of estimates and trends in infant mortality estimated from DHS data; second, to the interpretation of what the authors consider to be a ‘low’ infant mortality rate in former communist countries given their level of economic development; and third, to the role of the health care infrastructure in countries of the former Soviet Union in producing these ‘low’ infant mortality levels. This comment argues that trends in infant mortality in Armenia and other CIS countries, although probably declining, are perhaps less certain than the authors allow, that existing evidence does not suggest that they are uniformly low by global standards, or that the health care systems in CIS countries are uniformly effective in reducing infant deaths.     

A critique of the “ultra‐high risk” and “transition” paradigm

The transdiagnostic expression of psychotic experiences in common mental disorder (anxiety/depression/substance use disorder) is associated with a poorer prognosis, and a small minority of people may indeed develop a clinical picture that meets criteria for schizophrenia. However, it appears neither useful nor valid to observe early states of multidimensional psychopathology in young people through the “schizo”‐prism, and apply misleadingly simple, unnecessary and inefficient binary concepts of “risk” and “transition”. A review of the “ultra‐high risk” (UHR) or “clinical high risk” (CHR) literature indicates that UHR/CHR samples are highly heterogeneous and represent individuals diagnosed with common mental disorder (anxiety/depression/substance use disorder) and a degree of psychotic experiences. Epidemiological research has shown that psychotic experiences are a (possibly non‐causal) marker of the severity of multidimensional psychopathology, driving poor outcome, yet notions of “risk” and “transition” in UHR/CHR research are restrictively defined on the basis of positive psychotic phenomena alone, ignoring how baseline differences in multidimensional psychopathology may differentially impact course and outcome. The concepts of “risk” and “transition” in UHR/CHR research are measured on the same dimensional scale, yet are used to produce artificial diagnostic shifts. In fact, “transition” in UHR/CHR research occurs mainly as a function of variable sample enrichment strategies rather than the UHR/CHR “criteria” themselves. Furthermore, transition rates in UHR/CHR research are inflated as they do not exclude false positives associated with the natural fluctuation of dimensional expression of psychosis. Biological associations with “transition” thus likely represent false positive findings, as was the initial claim of strong effects of omega‐3 polyunsatured fatty acids in UHR samples. A large body of UHR/CHR intervention research has focused on the questionable outcome of “transition”, which shows lack of correlation with functional outcome. It may be more productive to consider the full range of person‐specific psychopathology in all young individuals who seek help for mental health problems, instead of “policing” youngsters for the transdiagnostic dimension of psychosis. Instead of the relatively inefficient medical high‐risk approach, a public health perspective, focusing on improved access to a low‐stigma, high‐hope, small scale and youth‐specific environment with acceptable language and interventions may represent a more useful and efficient strategy.     

“Action potentials” in NEUROSPORA CRASSA, a mycelial fungus

Occasional spontaneous “action potentiais” are found in mature hyphae of the fungus Neurospora crassa. They can arise either from low-level sinusoidal oscillations of the membrane potential or from a linear slow depolarization which accelerates into a rapid upstroke at a voltage 5–20 mV depolarized from the normal resting potential (near − 180 mV). The “action potentiais” are long-lasting, 1–2 min and at the peak reach a membrane potential near −40 mV. A 2− to 8−fold increase of membrane conductance accompanies the main depolarization, but a slight decrease of membrane conductance occurs during the slow depolarization. Two plausible mechanisms for the phenomenon are (a) periodic increases of membrane permeability to inorganic ions, particularly H⁺ or Cl^- and (b) periodic decreases in activity of the major electrogenic pump (H⁺) of the Neurospora membrane, coupled with a nonlinear (inverse sigmoid) current-voltage relationship.Identification of action potential-like disturbances in fungi means that such behavior has now been found in all major biologic taxa which have been probed with suitable electrodes. As yet there is no obvious function for the events in fungi.     

“Active” and “passive” ecological restoration strategies in meta‐analysis

One of the means of creating a more robust methodology for ecological restoration involves reducing the gap between ecological theory and restoration practices. A common strategy to do so is using meta‐analysis to understand key drivers of restoration outcomes. “Active” and “passive” is a dichotomy often used to separate restoration strategies in such meta‐analyses. We investigate previously raised concerns about selection bias and subjective categorization of strategies. We promote a paired experimental design in future empirical research and propose the use of three categories of restoration strategy in lieu of “passive” and “active” to alleviate inconsistency in definitions and categorization.     

A stable, “near-haploid” mammalian cell line (Dipodomys ordii)

An established SV40-transformed cell line of Dipodomys ordii was cloned for selective loss of chromosomal material. A clone is described which has a modal chromosome number of 50 (in the normal diploid 2n=72), and has about 66% of the DNA content of normal diploid cells. Karyotype analysis shows that, although some chromosome rearrangement has taken place, 23 chromosomes are completely unpaired and 7 chromosomes are partially unpaired. Buoyant density analysis in neutral CsCl and Cs₂SO₄+Ag gradients of the DNA of this clone shows that there has been no selective retention or loss of any of the satellite DNA components present in D. ordii during the elimination of 34% of the genetic material.     

Antioxidant activities of Ptychopetalum olacoides (“muirapuama”) in mice brain

Ptychopetalum olacoides (PO) roots are used by Amazonian peoples to prepare traditional remedies for treating various central nervous system conditions in which free radicals are likely to be implicated. Following the identification of PO ethanol extract (POEE) free-radical scavenging properties in vitro, the aim of this study was to verify the in vivo antioxidant effect of POEE. Aging mice (14 months) were treated (i.p.) with saline, DMSO (20%) or POEE (100mg/kg body wt.), and the hippocampi, cerebral cortex, striata, hypothalamus and cerebellum dissected out 60 min later to measure antioxidant enzyme activities, free-radical production and damage to macromolecules. POEE administration reduced free-radical production in the hypothalamus, lead to significant decrease in lipid peroxidation in the cerebral cortex, striatum and hypothalamus, as well as in the carbonyl content in cerebellum and striatum. In terms of antioxidant enzymes, catalase activity was increased in the cortex, striatum, cerebellum and hippocampus, while glutathione peroxidase activity was increased in the hippocampus. This study suggests that POEE contains compounds able to improve the cellular antioxidant network efficacy in the brain, ultimately reducing the damage caused by oxidative stress.     

Small but Manifold – Hidden Diversity in “Spumella‐like Flagellates”

Colourless, nonscaled chrysophytes comprise morphologically similar or even indistinguishable flagellates which are important bacterivors in water and soil crucial for ecosystem functioning. However, phylogenetic analyses indicate a multiple origin of such colourless, nonscaled flagellate lineages. These flagellates are often referred to as “Spumella‐like flagellates” in ecological and biogeographic studies. Although this denomination reflects an assumed polyphyly, it obscures the phylogenetic and taxonomic diversity of this important flagellate group and, thus, hinders progress in lineage‐ and taxon‐specific ecological surveys. The smallest representatives of colourless chrysophytes have been addressed in very few taxonomic studies although they are among the dominant flagellates in field communities. To overcome the blurred picture and set the field for further investigation in biogeography and ecology of the organisms in question, we studied a set of strains of specifically small, colourless, nonscaled chrysomonad flagellates by means of electron microscopy and molecular analyses. They were isolated by a filtration‐acclimatisation approach focusing on flagellates of around 5 μm. We present the phylogenetic position of eight different lineages on both the ordinal and the generic level. Accordingly, we describe the new genera Apoikiospumella, Chromulinospumella, Segregatospumella, Cornospumella and Acrispumella Boenigk et Grossmann n. g. and different species within them.     

“Impoverished” and “enriched” living conditions influence the proliferation and survival of neurons in crayfish brain

New neurons are added to two bilateral clusters of neurons in crayfish brain throughout their lives. These interneurons are associated with the olfactory and accessory lobes, areas of the brain that receive primary olfactory information and higher order inputs from the visual and tactile receptor systems. The rate of cell proliferation in these four clusters, revealed by BrdU labeling, is sensitive to the living conditions of the animals: individuals isolated in small spaces (impoverished condition) exhibit a lower rate of cell proliferation in comparison to their siblings living together in larger areas (enriched condition), although both groups were fed to satiation. Reduction in the rate of proliferation can be measured 1 to 2 weeks after the animals are subjected to the impoverished condition. Counts of the labeled neurons that survive after 4 weeks of subjection to the two conditions show that fewer new neurons survive in the brains of animals that have lived for 2 weeks in the impoverished condition in comparison to their siblings living in the enriched conditions. Factors such as surface area, depth of water, and social interaction can all play a role in determining both the rate of new neuron production and the incorporation of the new neurons into the brain of freshwater crayfish. The results indicate a high degree of neuronal plasticity in the crayfish brain that is highly sensitive to the conditions under which the animals are kept. © 2000 John Wiley & Sons, Inc. J Neurobiol 45: 215–226, 2000     

“Ecological Armageddon” – more evidence for the drastic decline in insect numbers

The efficient use of nitrogen by crops can minimise environmental risks and maximise returns to farmers. Under organic farming systems, this can be achieved by adjusting the fertilisation management and/or using genetic variability. Seven durum wheat (Triticum durum) cultivars and three emmer (Triticum dicoccum) cultivars were assessed under an organic farming system over a non‐consecutive 4‐year period (2005–11) in Foggia (southern Italy). The objectives were to investigate the agronomic and qualitative characteristics, and to evaluate the agronomic efficiency and adaptability according to three N fertilisation levels (0, 40, 80 kg N ha^?1). A split‐plot design was used, with three replications in each year. Nine traits were investigated: heading time, plant height, seed yield, number of spikes m^?2, harvest index, specific weight, 1000‐seed weight, and protein and gluten contents. Increasing N to 80 kg ha^?1 increased plant height (+7.3%), seed yield (+22.1%), spike density (+16.6%), and protein (+9.8%) and gluten (+2.1%) contents. The emmer genotypes and the oldest durum wheat ‘Cappelli’ showed the highest protein and gluten contents (mean, 13.9%, 11.2%, respectively). The maximum N agronomic efficiency [AE(N)] and N recovery efficiency [RE(N)] were seen for the modern durum wheat cultivars under 40 kg ha^?1 N treatment: ‘Duilio’, ‘Iride’ and ‘Varano’. The significant correlation between AE(N) and RE(N) and the year of release of the durum wheat cultivars (r = 0.53, P < 0.05, F = 4.7 for AE(N) and r = 0.57, P < 0.01, F = 5.7 for RE(N), respectively; n = 14) showed that the genetic breeding of this species for high grain yield is associated with an increase in the efficiency of N fertiliser use under organic farming. The highly significant effect for the Genotype × Environment interaction (F = 18.1, P < 0.001) of seed yield indicate the possibility to select for stable genotypes across environments. Based on the additive main effects and multiplicative interaction analysis, and the yield stability index, the varieties ‘Iride’ and ‘Varano’ show high‐stability responses and good seed yields under all N fertiliser treatments. Therefore, these varieties can be recommended for organic farming systems in Mediterranean areas.     

Proximate Composition and Nutrient Elements in the “Unusual” Algal “Jellies” of Lake Oguta in Southern Nigeria

The proximate composition, nutrient and trace elements of the planktonic algal “jellies” of Lake Oguta in Southern Nigeria, are provided as guides to their utilization and control, using flood (rainy) and dry season samples. These “jellies” are an unusual, macroscopic planktonic algal community in the lake, made up mostly of blue-green algae (Microcystis, Anabaena, Chroococcus) with some green algae (e. g. Spirogyra) and pennate diatoms (e.g. Navicula) rather epiphytic on the mucous jellies of the blue-green algae. Water content was high (98.2% mean, range 97.5-99.5%). Ash, protein and fat had values of 41.7 (39.0-46.2%), 16.9 (15.6-19.4%), and 2.0 (1.7-2.1%) respectively. Crude fibre and carbohydrates were high (25.8% and 12.4%). The levels of phosphorus and nitrogen were rather high, so were the major cations whose order of dominance (Ca > K > Mg > Na) differed from that of the lake water. Macronutrients increased in their concentrations during the rainy flood season while the reverse was the case with the micronutrients. Diagenesis of the endogenic minerals rather than anthropogenic factors are thought to be the reason for the seasonal changes in the ionic concentrations. Possible uses of the algal jellies are discussed as well as their control options.     

The Exceptional “Blind” Gut of Appendicularia sicula (Appendicularia, Tunicata)

In this work, we studied for the first time the histology and ultrastructure of the gut of Appendicularia sicula and demonstrated the absence of any trace of anus. Appendicularians are small holoplanktonic tunicates, characterised by very fast ingestion and quick food transfer along their gut. The high production of faecal pellets released in the aqueous environment, associated with a high filtration rate, highlights their important role in marine ecosystems. Due to the absence of an anus, in contrast with other appendicularians, A. sicula, one of the smallest species, accumulates undigested faecal material within its body, with consequent extreme enlargement of its rectum. The gut, the epithelium of which is generally extremely reduced, is formed of an oesophagus, a globular stomach, thin proximal and mid-intestine, and a huge rectum. The latter, when filled with faecal material, may occupy most of the volume of the trunk in fully grown specimens. Although profoundly altered, the gut of these animals does show several similarities to that of Fritillaria (a genus of the same family, Fritillariidae), with which it has in common many features such as specialised mitochondrial pump cells. In A. sicula, the structural simplifications of organs seem to reach their extreme condition in comparison to other appendicularians.     

Novel antiplatelet and antithrombotic activities of essential oil from Lavandula hybrida Reverchon “grosso”

Lavender extracts are known to produce several mild effects at central and peripheral level. However, no studies are so far available about the potential effects of lavender essential oil on the hemostatic system. In this work, we demonstrated antiplatelet properties of lavender oil towards platelet aggregation induced by arachidonic acid, U46619, collagen and ADP (IC₅₀=51, 84, 191 and 640 μg/ml, respectively) on guinea-pig platelet rich plasma (PRP) and its ability to destabilize clot retraction (IC₅₀=149 μg/ml) induced by thrombin on rat PRP.

Furthermore, antithrombotic properties were studied in an in vivo model of pulmonary thromboembolism induced by intravenous injection of a collagen–epinephrine mixture in mice subacutely treated with lavender oil. In this model, lavender oil (100 mg/kg/day os for 5 days) significantly reduced thrombotic events without inducing prohemorrhagic complications at variance with acetylsalicylic acid used as reference drug. Finally, main components of the oil were studied in vitro in order to assess their antiplatelet effects, but none of them possessed an activity comparable to the oil itself. These results provide the first experimental evidence of lavender oil's antiplatelet/antithrombotic properties which could be due to a synergistic effect of its components.     

A review of the molecular evidence for ballast water introduction of the toxic dinoflagellates Gymnodinium catenatum and the Alexandrium “tamarensis complex” to Australasia

The potential of ballast water to act as a major introduction vector for toxic dinoflagellates and other phytoplankton is beyond doubt; however, evidence that links the suspected introduced species with a source population is less convincing, especially without supporting historical and biochemical data, or consideration of palaeobiogeographical scenarios that may explain current species distributions. This paper presents new molecular data based on LSU-rDNA and rDNA-ITS sequences that demonstrate an unequivocal and recent link between Temperate Asian and Australasian populations of the toxic dinoflagellates Gymnodinium catenatum and toxic strains of the Alexandrium “tamarensis complex”. We integrate our data with supporting evidence from historical distribution records, sediment dating studies, toxin profiles, mating studies and previous molecular studies. We contrast the observed patterns of genetic and biochemical variation with those expected from various palaeobiogeographical scenarios explaining the evolution and natural dispersal of both species. While definitive proof is impossible, the total evidence indicates that these toxic dinoflagellates were introduced to Australasia during the past 100 years, most probably via ballast water from bulk-cargo shipping from Japan and/or south-east Asia.     

Sphenophyllum miravallis Vetter and Bowmanites cupulatus sp.n. from the “Illinger Flözzone” (“Heusweiler Schichten”, Lower Stephanian, Saar Basin, German Federal Republic)

This paper deals with a detailed study of Sphenophyllum miravallis Vetter, a member of the “Sphenophyllum thonii group”. New material from the Reisbach colliery, working the “Illinger Flözzone” of the “Heusweiler Schichten” (Lower Stephanian, Saar Basin, German Federal Republic), is described morphologically and anatomically, and the species is discussed. The new material enlarges the known range of variability of the normal aspect of the foliage, i.e. the foliage of the thinner branches. Thicker stems with their aberrant polymorphous foliage, and cellular details, are described for the first time. An emended diagnosis is given. Comparisons with other species are made.

The new species Bowmanites cupulatus is introduced to accommodate fructufications most probably belonging to Sphenophyllum miravallis.

S. crenulatum Knight ex Wagner is considered to be a heterotypic synonym of S. miravallis, the latter name having priority.     

Comparative study of the molecularly imprinted polymers prepared by reversible addition–fragmentation chain transfer “bulk” polymerization and traditional radical “bulk” polymerization

Bisphenol A (BPA) and propranolol‐imprinted polymers have been prepared via both reversible addition–fragmentation chain transfer “bulk” polymerization (RAFTBP) and traditional radical “bulk” polymerization (TRBP) under similar reaction conditions, and their equilibrium binding properties were compared in detail for the first time. The chemical compositions, specific surface areas, equilibrium bindings, and selectivity of the obtained molecularly imprinted polymers (MIPs) were systematically characterized. The experimental results showed that the MIPs with molecular imprinting effects and quite fast binding kinetics could be readily prepared via RAFTBP, but they did not show improved template binding properties in comparison with those prepared via TRBP, which is in sharp contrast to many previous reports. This could be attributed to the heavily interrupted equilibrium between the dormant species and active radicals in the RAFT mechanism because of the occurrence of fast gelation during RAFTBP. The findings presented here strongly demonstrates that the application of controlled radical polymerizations (CRPs) in molecular imprinting does not always benefit the binding properties of the resultant MIPs, which is of significant importance for the rational use of CRPs in generating MIPs with improved properties. Copyright © 2013 John Wiley & Sons, Ltd.     

“Candidatus Phytoplasma asteris” and “Candidatus Phytoplasma mali” strains infecting sweet and sour cherry in the Czech Republic

A survey for phytoplasma diseases was conducted in a sweet and sour cherry germplasm collection and in cherry orchards within the Czech Republic during 2014–2015. Phytoplasmas were detected in 21 symptomatic trees. Multiple infections of cherry trees by diverse phytoplasmas of 16SrI and 16SrX groups and 16SrI‐A, 16SrI‐B, 16SrI‐L, 16SrX‐A subgroups were detected by restriction fragment length polymorphism (RFLP). Nevertheless, phylogenetic analysis placed subgroups 16SrI‐B and 16SrI‐L inseparable together onto one branch of phylogenetic tree. This is the first report of subgroups 16SrI‐A and 16SrI‐L in Prunus spp., and subgroup 16SrX‐A in sour cherry trees. Additionally, novel RFLP profiles for 16SrI‐A and 16SrI‐B‐related phytoplasmas were found in cherry samples. Phytoplasmas with these novel profiles belong, however, to their respective 16SrI‐A or 16SrI‐B phylogenetic clades.