Independence of Protein Synthesis and Drug Uptake in Nerve Cell Bodies and Glial Cells isolated by a New Technique

A severe handicap in any study of the cellular biochemistry of the brain is the unavailability of sufficient amounts of pure neurones and glial cells. Many efforts to separate one from the other have been made¹, but only four basic types of isolation procedures have been described for routine use: (1) brain is treated with a mixture of acetone-glycerol and water before mincing and centrifugation^3–5; (2) brain mince is sieved and subjected to gradient centrifugation¹,^6–8—this separates neuronal cell bodies from neuropil⁶ or from intact but rather contaminated glial cells⁸; (3) whole brain is disrupted in a tissue press and zonal centrifugation is used to separate cellular and subcellular components as they leave the zonal centrifuge rotor⁹; and (4) chopped brain is incubated in oxygen at 37° C in the presence of 1 % (w/v) trypsin¹⁰, a treatment which, in our estimation, severely prejudices this technique's general usefulness, because it precludes meaningful comparative investigations of enzymes and non-enzymatic structural and/or soluble cell proteins. Since investigations of the latter type are the aim in our laboratory, we needed a technique in which brain is not subjected to deleterious treatments such as immersion in acetone-glycerol-water mixtures^3–5 or trypsinization¹⁰ and in which no special instrumentation⁹, tissue presses⁹ or homogenizers⁸ are required. We now report a technique which successfully accomplishes this objective, for it makes possible the isolation of highly purified neuronal perikarya and of intact glial cells from a few grams of brain, in yields which permit the subsequent subcellular fractionation of the isolated cells. We also report two applications of the new technique which have enabled us to determine the in vivo time course of protein synthesis in and the uptake of the radioactive convulsant agent methionine sulphoximine^11,12 by, the neurones and the glial cells of the immature rat brain cortex.     

Host plant defences and voltinism in European butterflies

Abstract.  1. With respect to seasonal availability for herbivores, plants defended by synthesising qualitative compounds differ from those protected by accumulation of quantitative macromolecules, leaf toughness, and low water and/or nutrient content. While the palatability of the former plants remains relatively constant during the season, the palatability of the latter group decreases with leaf age.
2. It was hypothesised that in seasonal temperate environments, quantitative plant defences should restrict the annual numbers of insect generations. To test this hypothesis, European butterflies were used as a model, both non-corrected regressions and tests controlling for phylogeny were carried out, and potentially confounding factors such as body size or occurrence in short-season environments were treated as covariables.
3. Non-phylogenetically controlled regressions corroborated that butterflies feeding on quantitatively protected hosts (woody plants + grasses) form fewer generations than species feeding on qualitatively protected forbs. Plant defences fitted voltinism better than butterfly size, and remained significant even after controlling for short seasons. Using independent contrasts, feeding on woody plants plus grasses, and feeding on woody plants only, predicted fewer generations. These patterns, however, applied exclusively for foliage-feeding species.
4. The association between plant defences and voltinism represents a hitherto overlooked pattern in the ecology of temperate herbivores. It may explain why large insects tend to form fewer generations and feed on structurally complex hosts, and why some species remain monovoltine although they are not restricted by short season.     

Rotoitidae, a curious new family of Chalcidoidea (Hymenoptera) from New Zealand

Abstract. A new chalcidoid family, Rotoitidae fam.n., is described from New Zealand. The probable systematic affinities of Rotoitidae are discussed and the type genus and a single included species, Rotoita basalis gen. et sp.n., are described and illustrated.     

Taxonomy, distribution and nomenclature of three confused broad-leaved Potamogeton species occurring in Africa and on surrounding islands

A taxonomic revision of broad-leaved Potamogeton species ascribed to the ' P. schweinfurthii–thunbergii complex' occurring in Africa and on surrounding islands is presented. Three species, P. nodosus , P. richardii and P. schweinfurthii , are recognized in the African mainland. The widespread species P. nodosus has been widely overlooked in sub-Saharan Africa. It is recorded here for the first time from eight countries of tropical and southern Africa and from six surrounding islands. The distribution of P. richardii is critically revised and the species is recorded for the first time from Cameroon, Swaziland and Madagascar. P. schweinfurthii is recorded for the first time from Algeria, Tunisia, Burkina Faso and Niger. The nomenclature of all three species is revised. Lectotypes are designated for six names. All original material of the name P. thunbergii Cham. et Schltdl. actually belongs to P. nodosus Poir. The correct name for the East and southern African species called ' P. thunbergii ' is P. richardii Solms. The lectotype of P. schweinfurthii designated by Dandy proved to be P. nodosus . A new type is therefore proposed for the species generally named P. schweinfurthii and the name itself is proposed for conservation. The morphology and stem anatomy of P. nodosus , P. richardii and P. schweinfurthii are described. In spite of some overlaps in the morphological variation in their vegetative characters, a detailed analysis of the variation patterns and instructions for reliable identification are given. The distributions of all three species are described, based solely on reliably identified specimens, many of which were also examined anatomically. Distribution maps are provided.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 329–357.     

COEFFICIENTS OF ASSOCIATION AND SIMILARITY, BASED ON BINARY (PRESENCE-ABSENCE) DATA: AN EVALUATION

Forty-three association (similarity) coefficients were collected and evaluated in this survey. Some of them are synonyms or direct correlates with earlier described indices (A₈, A₉, A₁₂, A₃₁, A₃₃), others are mere transforms from one range of values to another (A₁₀, A₂₄, A₃₃). Several coefficients are incompatible with suggested admissibility conditions of the minimum-maximum value (A₁₃, A₁₆, A₂₇, A₂₈, A₂₉, A₃₁), symmetry (A₁, A₂, A₁₃, A₁₆, A₂₆), discrimination between positive and negative association (A₂₇, A₂₈, A₃₁) or monotonicity with (χ²) (A₁₉, to A₂₄); A₁₇ yields very low and erratic values. As a result, 23 coefficients were excluded and the remaining 20 measures were subjected to an empirical trial on interspecific association data among fungi of the genus Chaetomium, with the use of a cluster analysis. The classification produced five main clusters of related coefficients, with several subgroups. It was then demonstrated that representative indices from different clusters yield different dendrograms of interspecific association among Chaetomium, and A₃₄, A₁₄, possibly also A₃₆ and A₄₀ seemed to be less sensible. A set of measures that generally work well (at least in the interspecific association) comprises A₄ (Jaccard), A₄ (Dice-Sφrensen), A₇ (Kulczyński), A₁₁ (Driver-Kroeber-Ochiai) and, with some reservation A³⁰ (Pearson tetrachoric) and A₃₂ (Baroni-Urbani-Buser). For some purposes, however, other ‘admissible’ coefficients would be more optimal, and the choice of a measure should be related to the nature of the data. It is tentatively suggested that three or so alternative coefficients be used and the results compared on the same data basis; moreover, significance tests on association should be carried out whenever possible.     

An Electron Microscope Study of Autoinfection in Neogregarines (Sporozoa, Neogregarinida)

SYNOPSIS. In an electron microscope study of the neogregarine Farinocystis tribolii Weiser 1953 in the fat body of the larvae of the flour beetle Tribolium castaneum , empty oocysts and adjacent sporozoites of the gregarine were found. The empty oocysts contained host cell cytoplasm, a residuum only slightly larger than that in mature oocysts, and some remnants of the oocyst membrane pressed tightly against the inner surface of the wall. Apparently normal sporozoites were found near the empty oocysts and no damaged ones were seen. It is assumed that the sporozoites go on developing in the host, i.e., that autoinfection takes place.     

Cluster biodiversity as a multidimensional structure evolution strategy: checkerspot butterflies of the group Euphydryas aurinia (Rottemburg, 1775) (Lepidoptera: Nymphalidae)

In the present paper, we explore the evolution of cluster structure in closely related species in the Euphydryas aurinia complex based on morphological (wing pattern, genital armatures) and molecular (cytochrome c oxidase subunit I) characters. Male genitalia differ in the length and shape of the uncus, harpe and juxta branches, by the shape of some parts of the phallus, and by the amount of spikes on the ventral section of the valva. The main trends in the vertical distribution of the E. aurinia group are dwarfism with increasing altitude, coupled with enlargement of paler and darker‐coloured elements of the wing pattern, increasing the overall contrast. Unlike the Euphydryas maturna, the E. aurinia complex forms many local populations specialized under different ecological conditions, probably affected by different evolutionary scenarios. The phylogenetic analysis of the group reveals two ecologically distinct subgroups: one associated with the boreal forest‐mesophyllic meadow biome and one associated with the xeromesophyllic steppe biome. Within each group, two major ecological strategies have evolved in parallel: montane and lowland. Based on the results of the analyses, we revise the nomenclature as follows: E. aurinia pyrenesdebilis (Verity, 1928), stat. rev. (= debilis Oberthür, 1909, syn.n. , nomen nudum), E. aurinia bulgarica (Fruhstorfer, 1916), stat. rev. , E. aurinia provincialis (Boisduval, 1828), stat. rev. and E. beckeri (Lederer, 1853), stat. rev. The following name‐bearing types are designated: neotype of Papilio aurinia Rottemburg, 1775, neotype of Papilio merope de Prunner, 1798, lectotype of Melitaea beckeri Lederer, 1853, and lectotype of Melitaea aurinia banghaasi Seitz, 1908. All name‐bearing types are figured. A new subspecies, Euphydryas laeta ostracon Korb, Bolshakov, Fric, ssp.n. , is described (type locality by holotype data: Kazakhstan, Vostochno‐Kazakhstanskaya Oblast, Shemonaikha).     

Mark–recapture on large spatial scale reveals long distance dispersal in the Marsh Fritillary,Euphydryas aurinia

1. Long distance dispersal (LDD), or movements far beyond the occupied habitat borders, maintains the integrity of metapopulations in fragmented landscapes. Recent studies on butterflies increasingly reveal that LDD exists even in species that were long regarded as sedentary. Mark–recapture (MR) studies covering larger study areas typically reveal movements among distant colonies. 2. We studied dispersal of the EU‐protected, regionally endangered Euphydryas aurinia Rottemburg butterfly in the Czech Republic, using two complementary MR approaches. The single system study was carried out for eight seasons within 30 habitat patches covering 28 ha. The multiple populations study was carried out for a single season, but covering almost all Czech colonies of the species (82 colonies, 110 distinct patches, total area 324 ha within ca 1500 km²). 3. Single system mean lifetime movements were consistently higher for males, but slopes of dispersal kernel power functions were shallower for females, implying that higher proportions of females crossed distances of several kilometres. 4. The multiple populations study allowed detection of 51 lifetime movements exceeding 5 km (41 males, 10 females) and 14 movements exceeding 10 km (13 males, 1 female). Both mean lifetime movements and slopes of the dispersal kernels varied among systems, with no consistent pattern between sexes. All Czech Republic populations are within 0.1% movement probability of both sexes, whereas 1% movement probability delimits three separate management units. 5. Dispersal predictions from local data underestimate total mobility, warning against the use of local MR data for extrapolating long‐distance movements. Local dispersal data, however, remain useful for analysing finer details of insect mobility.