Some theorems in topology and a possible biological implication

In a previous paper (Bull. Math. Biophysics,16, 317–48, 1954) a transformationT of one graph into another was suggested, which may describe the relations between organisms of different complexity. In this paper some topological properties of the transformationT are studied. It is shown that the fundamental group of the transformed graph is homomorph to the fundamental group of the original graph. An expression is derived for the number of points in a point base of the transformed graph in terms of the number of points of the point base of the original when the point base of the latter consists only of residual points, and it is shown that the ratio of the number of points of the point base to the total number of points of the graph is in that case greater in the transformed graph than in the original. A combinatorial problem arising in connection with the transformationT is solved by deriving the number of possible ways in whichn-n _i indistinguishable elements may be arranged inn _i classes, permitting some of then _i classes to be empty. The possible biological meaning of the increased ratio of the number of points of the point base to the total number of points of the graph is discussed. It is suggested that it may be interpreted as a decrease of regenerating ability with increase of differentiation of the organism. Those considerations suggest the possibility of deriving some general biological laws from the consideration of the properties of the transformation only, regardless of the choice of the primordial graph.     

Urinary and serum biomarkers in ureteropelvic junction obstruction: a systematic review

Abstract

Context: Ureteropelvic junction obstruction (UPJO) constitutes a predominant cause of obstructive hydronephrosis. Fundamental questions regarding the assessment and treatment of infants and children with obstructive nephropathy remain unanswered.

Objective: Several studies have investigated the usefulness of substances that could serve as potential diagnostic and prognostic biomarkers in children with UPJO. Aim of the present study is to systematically review the literature on biomarkers that have been studied to date in patients with UPJO.

Methods: The main search was conducted in the electronic databases MEDLINE and Cochrane Central Register of Controlled Trials (CENTRAL) from inception through March 2014 using various combinations of Medical Subject Headings (MeSH).

Results: The 14 included studies reported data on 380 UPJO patients who underwent surgery, 174 who were treated conservatively and 213 controls.

Conclusion: Some biomarkers offer promising results however more multicenter, prospective carefully designed studies are needed to evaluate their diagnostic and prognostic value.     

The effect of polyphenolic extract from pine bark,Pycnogenol® on the level of glutathione in children suffering from attention deficit hyperactivity disorder (ADHD)

Abstract

Attention deficit hyperactivity disorder (ADHD) belongs to the neurodevelopmental disorders characterized by impulsivity, distractibility and hyperactivity. In the pathogenesis of ADHD genetic and non-genetic factors play an important role. It is assumed that one of non-genetic factors should be oxidative stress. Pycnogenol^®, an extract from the pine bark, consists of bioflavonoids, catechins, procyanidins and phenolic acids. Pycnogenol^® acts as powerful antioxidant, chelating agent; it stimulates the activities of some enzymes, like SOD, eNOS, and exhibits other biological activities.

Aim: The aim of this randomized, double-blind, placebo-controlled trial was to investigate the influence of administered Pycnogenol^® or placebo on the level of reduced (GSH) and oxidized (GSSG) glutathione in children suffering from ADHD and on total antioxidant status (TAS). This is the first investigation of the redox glutathione state in relation to ADHD.

Results: One month of Pycnogenol^® administration (1 mg/kg body weight/day) caused a significant decrease in GSSG and a highly significant increase in GSH levels as well as improvement of GSH/GSSG ratio in comparison to a group of patients taking a placebo. TAS in children with ADHD was decreased in comparison with reference values. Pycnogenol^® administration normalizes TAS of ADHD children.     

Winter territoriality and its implications for the breeding ecology of White-throated Dippers Cinclus cinclus

Capsule: Pairs of White-throated Dippers Cinclus cinclus which defended winter territories bred earlier than non-territorial individuals, but there was no difference in reproductive success.

Aims: The effect of winter territoriality on breeding ecology has rarely been studied in resident birds. We carried out a preliminary investigation of whether winter territorial behaviour and territory size affect the timing of reproduction, breeding territory size and reproductive success in a riverine bird, the White-throated Dipper.

Methods: We monitored an individually marked population of White-throated Dippers in the UK. Wintering individuals were classified as either territorial or ‘floaters’ according to their patterns of occurrence and behaviour, and their nesting attempts were closely monitored in the subsequent months. Winter and breeding territory sizes were measured by gently ‘pushing’ birds along the river and recording the point at which they turned back.

Results: All birds defending winter territories did so in pairs, but some individuals changed partners before breeding. Territorial pairs that were together throughout the study laid eggs significantly earlier than pairs containing floaters and those comprising territorial birds that changed partners. However, there were no significant differences in clutch size, nestling mass or the number of chicks fledged. There was no relationship between winter territory length and lay date or any measure of reproductive success, although sample sizes were small. Winter territories were found to be significantly shorter than breeding territories.

Conclusion: Winter territoriality may be advantageous because breeding earlier increases the likelihood that pairs will raise a second brood, but further study is needed. Territories are shorter in winter as altitudinal migrants from upland streams increase population density on rivers, but this may also reflect seasonal changes in nutritional and energetic demands.     

Germination of stored and scarified seeds of Passiflora caerulea L. (Passifloraceae)

Abstract

This work evaluates the influence of storage and scarification in the germination of Passiflora caerulea L., in order to acquire the necessary knowledge to cultivate this economically important species. Seeds stored one month under different conditions (no storage, fermentation, desiccation) were submitted to various pre‐treatments (aril removal, mechanical and chemical scarification or combinations of these). Emergence was recorded periodically for 11 months in a greenhouse. Germination time, germination percentage and germination speed were calculated. Histochemical tests were applied to seeds maintained under the three storage conditions, for observing possible changes in the integument and storage tissue. Viability was maintained at least for the storage period tested, as germination occurred after that time. Because the seeds stored under desiccation germinated, the species is orthodox. Chemical scarification prevented germination in most cases. Although germination levels were low, they were higher in stored seeds (fermented and desiccated) than in fresh ones. Fermented seeds (which exhibited no storage tissue and less lignin in the integument) devoid of the aril germinated earlier, faster and in greater quantity. The type of dormancy of this species is discussed.     

Validation of <Emphasis Type="Italic">Neoraputia</Emphasis> (Galipeae,Rutaceae) and description of two new species from Eastern Brazil

The name Neoraputia was published without citation of the type, making it and the names of the four species transferred to it invalid. The genus name and combinations are validated here. Lectotypes are chosen for the basionyms, Aruba alba, Raputia magnifica, R. paraensis, and Raputia trifoliata. Two new species, Neoraputia micrantha and N. calliantha, from forests of eastern Bahia, Brazil, are described.     

Measurements and monitoring of the hydrogen and deuterium contents in the plasma of the L-2M stellarator

The program of experiments on ITER includes a sequential change of the plasma isotopic composition from pure hydrogen plasma in the initial stage of research to deuterium and, then, deuterium-tritium plasma with a gradual increase in the tritium content. In this context, the influence of the plasma isotopic composition on the processes of plasma heating and confinement are being actively studied on the existing tokamaks and stellarators. The plasma isotopic composition also depends on the composition of the gas desorbed from the vacuum chamber wall in the course of recycling. Therefore, the rate of change of the plasma isotopic composition after altering the injected gas also depends on the rate of change of the isotopic composition of the gas absorbed in the wall. These effects were studied in the experiments carried out on the L-2M stellarator in which the working gas was changed from hydrogen to deuterium. Spectral measurements of the intensity ratio between the H _α and D _α lines made it possible to monitor the isotopic composition of the plasma in the course of cleaning of the chamber wall from earlier absorbed hydrogen and its replacement with deuterium. After returning to hydrogen, the rate of cleaning of the wall from deuterium was also determined. The results of these experiments show that the plasma isotopic composition varies exponentially with the number N of shots after transition to another isotope, ∼exp(−N/47). Hence, the isotopic composition can be changed almost completely over 2 to 3 working days. This allows one to study the influence of the plasma isotopic composition on plasma confinement during the same experimental session.     

Controlled Topical Delivery of Hydrocortisone and Mannitol Via Select Pathways

Abstract

In an earlier report (1) we described the controlled follicular delivery of hydrophobic macromolecules from nonionic lipid-based formulations composed of glyceryl dilaurate (GDL), cholesterol (CH), and polyoxyethylene-10-stearyl ether (POE-10). However, the influence of lipid composition on topical delivery of marginally hydrophobic and hydrophilic drugs from these nonionic lipid-based systems has not been investigated. In this report we describe the effect of variation of GDL to POE-10 ratio in the nonionic lipid-based formulations on the extent and route of delivery of hydrocortisone and mannitol, a marginally hydrophobic and hydrophilic model drug, respectively, into and through hairless mouse skin mounted on Franz diffusion cells. The results indicate that the extent of hydrocortisone uptake increased with increasing GDL to POE-10 weight ratio whereas mannitol uptake was quite the opposite and decreased with increasing GDL to POE-10 weight ratio. The diametrically opposite trends for the two drug markers suggests strongly that hydrocortisone and mannitol are transported into and across skin from the nonionic lipid-based formulations via two distinctly different routes. Further, the finding from microautoradiographic studies that the delivery of hydrocortisone from nonionic lipid-based lipid melt formulations was predominantly across the transfollicular route compared to its transport across both the trans-epidermal and transfollicular pathways from nonionic lipid-based liposomes, suggests that it is possible to tailor formulations for specific and targeted delivery across a certain route.     

Variation in species richness within and between calcareous (alvar) grassland stands: the role of core and satellite species

Anoda cristata is a widelydistributed annual weed in Mexico, which grows as agrestal or naturally indisturbed and undisturbed vegetation, respectively. Plants of this species aretolerated in orchards and corn-bean fields by Mexican ethnic groups ofCentral Mexico. Leaves of the plants are used as a food source, andoccasionallyseeds are sown in orchards. Because Mexicans have used Anodacristata for a long time, it is possible that ecological andmorphological characteristics of managed populations differ from those of wildpopulations. In this study, we analyzed phenotypic responses of two populationsof A. cristata (wild and agrestal) growing in twohabitats (forest and cultivated field) comparing survivorship, andlife history traits. Natural progenies from wild and agrestal populations ofA. cristata were transplanted into a cultivated field andin the understory of a pine forest in a reciprocal transplant experiment.Results showed that the habitat of transplant and the origin of populations hadsignificant effect on all plant characters measured (growth, phenology, andbiomass allocation), but the habitat x origin interaction wasnon-significant. In general, plants from the agrestal population grewfaster, reproduced earlier, and allocated more biomass to reproduction, thanplants from the wild population. Similarly, significant effects of habitat andorigin on plant survivorship were detected, but the origin of populationsexplained the largest proportion of variance in plant survival. Most traitswerephenotypically plastic but there were no differences in the magnitude ordirection of the response between populations. In contrast both populationsshowed differentiation for most character mean values. Populationdifferentiation is possibly the result of genetic differences driven byprocesses other than incipient domestication.     

PET-based quantification of statistical properties of hypoxic tumor subvolumes in head and neck cancer

PurposePET hypoxia imaging of head and neck cancer (HNC) has the potential to stratify the response to radiochemotherapy. The aim of this work was to quantify the statistical properties of hypoxic tumor subvolumes measured by PET, and their impact on failure rate of standard chemoradiation.MethodsA PubMed search was undertaken to identify relevant publications between 2001 and July 2015, containing original data regarding the properties of HNC hypoxic subvolumes and their evolution during therapy, measured using specific PET tracers.ResultsThe number and intensity of hypoxic voxels is significantly reduced during therapy. Patients are 4.2 times more likely to have negative outcome if baseline hypoxic. The change of the hypoxic volume during therapy, as well as the statistical distribution of the hypoxic fraction (HF), is quantified and analyzed. HF strongly correlates with the median T/M (tumor-to-muscle) SUV (standard uptake value) ratio, but not with gross tumor volume. Hypoxia is 2.2 times more frequently manifest in T3 + T4 than in T1 + T2 primary tumors. Calculated quantities are presented for primary and nodal tumors separately, where available.ConclusionsAlthough hypoxia diminishes during chemoradiation, it is a major predictor of outcome. HF, if large enough, can be predicted from the median T/M SUV ratio. CT-delineated gross tumor size does not influence the percentage of hypoxic voxels. Primary tumors are less likely hypoxic at an earlier stage.     

Revision of <Emphasis Type="Italic">Heterosavia</Emphasis>, stat. nov., with notes on <Emphasis Type="Italic">Gonatogyne</Emphasis> and <Emphasis Type="Italic">Savia</Emphasis> (Phyllanthaceae)

Heterosavia (Phyllanthaceae) is segregated from Savia (tribe Bridelieae), recognized at generic rank, and placed in tribe Phyllantheae. Floral, fruit, leaf anatomical, leaf venation, and pollen characters of the neotropical taxa previously united as Savia including Gonatogyne are discussed and illustrated. Keys to the three genera and to the species of Heterosavia are presented. Four species (all new combinations), Heterosavia bahamensis, H. erythroxyloides, H. laurifolia, and H. maculata, are recognized. The new combinations Heterosavia laurifolia var. intermedia and H. maculata var. clementis are proposed. The names Heterosavia, H. erythroxyloides, H. laurifolia, Savia clementis, S. clusiifolia, S. clusiifolia var. fallax, and S. longipes are lectotypified. Distribution maps and conservation assessments (IUCN ratings) of Heterosavia species and varieties are provided.     

Lipase-catalyzed synthesis of medium- and long-chain diesters of 2-oxoglutaric acid

Abstract

The influence of various reaction parameters, such as alcohol-to-substrate ratio, enzyme-to-substrate ratio, solvent and temperature, on the enzymatic preparation of a series of novel medium- and long-chain esters of 2-oxoglutaric acid has been evaluated. Among the tested lipases, those from Candida antarctica and Carica papaya appeared to be the best catalysts. Mild reaction conditions and low environmental impact make the biocatalytic procedure a convenient way to prepare the reported products, which are potential fat substitutes in the food industry.     

Genetic relationships among wild and cultivated blackberries (Rubus caucasicus L.) based on amplified fragment length polymorphism markers

Abstract

Rubus is a large genus of flowering plants in the rose family, Rosaceae, subfamily Rosoideae. The blackberries, as well as various other Rubus species with mounding or rambling growth habits, are often called brambles. Little information is available on the genetic diversity of wild-grown blackberries. The objective of this study was to determine the genetic relationships among nine promising (high-yield capacity, free of pest and diseases, better fruit traits) wild blackberry (Rubus caucasicus L.) selections and the well-known cultivar, “Chester” by using amplified fragment length polymorphism (AFLP) markers. Genotypes were evaluated with three selective primer-enzyme combinations, producing a total of 223 AFLP fragments with 53% polymorphism ratio. Clustering of genotypes using unweighted pair-group method of arithmetic average cluster analysis clearly separated groups of wild blackberry genotypes while the variety “Chester” was clustered independently. Wild selections represented a distinct germplasm source on the basis of the estimated genetic distance among them. Genetic diversity data from this study will be helpful in using and exploiting the wild genetic material for breeding purposes as well as for further research.     

Sibling and environmental correlates of adolescents’ perceptions of family environments: Ethnic group differences

Abstract

Hierarchical regression analyses and response surfaces were used in an investigation of relationships between sibling variables and adolescents’ perceptions of their family environments, after the impact on the perceptions of earlier family measures was taken into account. The analyses involved Australian adolescents and included 260 Anglo‐Australian, 120 Greek, and 90 Southern Italian families. Regression models included terms to test for possible linear, interaction, and curvilinear associations between the sibling and family environment variables. The analysis suggested the propositions that: (a) parents from different ethnic groups create different learning environments for their children and that there are ethnic‐group variations in how children perceive their family environments, (b) there are ethnic‐group variations in relationships between sibling variables and adolescents’ perceptions of their parents’ support for learning, and (c) within ethnic groups the relationships between sibling variables and perceived parental support for learning differ, depending on whether the support of fathers or mothers is being considered.     

Comparison of urinary aflatoxin M1 and aflatoxin albumin adducts as biomarkers for assessing aflatoxin exposure in Tanzanian children

Purpose: To determine levels of urinary aflatoxin M1 (AFM1) in children and correlate the concentrations with previously reported aflatoxin albumin adduct (AF-alb) levels in these children.

Materials and methods: Matched urine and blood samples were collected from 84 Tanzanian children aged 6–14 months old. From 31 children in one village (Kigwa), samples were collected at three time points six months apart. Samples were collected from 31 and 22 children from two different regions at the second time point only. Urinary AFM1 was measured using a commercial enzyme-linked immunosorbent assay (ELISA) kit with a modified protocol to improve sensitivity. AF-alb was measured using an established ELISA method.

Results: The relative ranking of the three villages for exposure to aflatoxin based on either AFM₁ or AF-alb biomarker measurements was the same. In Kigwa village, both AFM1 and AF-alb levels were higher at six months post-harvest compared to baseline. However, at the next visit, the AFM1 levels dropped from a GM (interquartile range) of 71.0 (44.7, 112.6) at visit two to 49.3 (31.5, 77.3) pg/ml urine, whereas AF-alb levels increased from 47.3 (29.7, 75.2) to 52.7 (35.4, 78.3) pg/mg albumin between these two visits, reflecting the fact that AFM1 measures short-term exposure, whereas AF-alb measures longer term exposure. There was a correlation between AFB1 intake and AFM1 excretion (r=?0.442, p?≤?0.001).

Conclusions: Urinary AFM1 is a good biomarker for AFB1 exposure in Tanzanian children, reflecting geographical and temporal variations in exposure to this foodborne toxin.     

Phytoplankton blooms and fish recruitment rate: Effects of spatial distribution

We consider the spatio-temporal dynamics of a spatially-structured generalization of the phytoplankton-zooplankton-fish larvae model system proposed earlier (Biktashev et al., 2003, J. Plankton Res. 5, 21–33; James et al., 2003, Ecol. Model. 160, 77–90). In contrast to Pitchford and Brindley (2001, Bull. Math. Biol. 63, 527–546), who were concerned with small scale patchiness (i.e., 1–10m), on which the (stochastic) raptorial behaviour of individual larvae is important, we address here the much larger scale ‘patchy’ problems (i.e., 10–100 km), on which both larvae and plankton may be regarded as passive tracers of the fluid motion, dispersed and mixed by the turbulent diffusion processes. In particular, we study the dependence of the fish recruitment on carrying capacities of the plankton subsystem and on spatio-temporal evolution of that subsystem with respect to the larvae hatching site(s). It is shown that the main features found both in the nonstructured and age-structured spatially uniform models are observed in the spatially structured case, but that spatial effects can significantly modify the overall quantitative outcome. Spatial patterns in the metamorphosed fish distribution are a consequence of quasi-local interaction of larvae with plankton, in which the dispersion of larvae by large scale turbulent eddies plays little part due to the relatively short timescale of the larvae development. As a result, in a strong phyto/zooplankton subsystem, with fast reproduction rate and large carrying capacity of phytoplankton and high conversion ratio of zooplankton, recruitment success depends only on the localization and timing of the hatching with respect to the plankton patches. In a weak phyto/zooplankton system, with slow reproduction rate and small carrying capacity of phytoplankton and low conversion ratio of zooplankton, the larvae may significantly influence the evolution of the plankton patches, which may lead to nontrivial cooperative effects between different patches of larvae. However, in this case, recruitment is very low.     

Effect of mating combinations on the host parasitisation and sex allocation in solitary endoparasitoid,Aenasius arizonensis (Hymenoptera: Encyrtidae)

Aenasius arizonensis (Girault) is an important solitary endoparasitoid of Phenacoccus solenopsis Tinsley. To optimise the mass production of high-quality females, it is important to assess the influence of mating regimes on the progeny fitness and sex allocation. We, therefore, hypothesise that mating combinations in A. arizonensis adults emerged from different host instars may influence parasitism and sex allocation in the subsequent generation. Therefore, we compared three nymphal instars (1st, 2nd and 3rd) and adults host stages of P. solenopsis for parasitism and sex allocation by A. arizonensis. Further, F₁ female progeny of the parasitoid emerged from different host instars was henceforth evaluated for its fitness in six mating combinations. A. arizonensis females parasitised all the host stages except the 1st instar nymphs. The parasitised 2nd instar nymphs yielded only males, while the sex ratio in the later host instars was strongly female-biased. The parasitoid females preferred 3rd instar nymphs with respect to higher parasitism (74.0–84.0%) and produced more females in the F₁ progeny as compared to other host stages. F₁ females that emerged from 3rd instar nymphs produced significantly higher parasitism (74.0–79.0%). These mating combinations also yielded more female progeny in the F₂ generation. However, parasitism by F₁ females was significantly lower (9.0–12.0%) when mated with males that emerged from 2nd instar P. solenopsis nymphs. Moreover, latter combinations yielded only male progeny in F₂ generation. These findings can be used in laboratory mass rearing of this parasitoid vis-à-vis biological control of P. solenopsis.     

The development of the Archidium capsule: clarification of a misconception

Abstract

Contrary to an earlier report that the spore sac in Archidium is endothecial in origin, evidence is presented from this earlier report on A. alternifolium and from observations on A. stellatum that the spore sac is amphithecial in origin as in the Bryideae. The retention of Archidium in the Archidiidae is supported on sporophytic evidence.     

New species and other nomenclatural changes for ferns from Bolivia

We describe 11 new pteridophyte species belonging to various families from Bolivia: Dennstaedtiaceae:Hypolepis, scandens, Hypolepis minima; Pteridaceae:Cheilanthes glutinosa, Eriosorus angustus, E. ascendens, E. madidiensis; Tectariaceae:Tectaria jimenezii; and Woodsiaceae:Athyrium latinervatum. Diplazium bipinnatum, D. bolivianum, D. yuyoense. The following new combinations are proposed:Anemia australis, Diplazium andicola, D. andinum, andD. petiolulatum.Polystichum maximum is proposed as a new name forPolystichum giganteum.     

« Chaetopsina ivoriensis » a new species of Dematiaceous Hyphomycetes

Abstract

The discover and morphological characters of a Dematiaceous Hyphomycetes are described. The material, studied under a morphological point of view directly collected on the natural substratum, allows us to establish the appartenance to the genus Chaetopsina. Since this species does not appeare described till now, the Authors propose for it the nomenclature ivoriensis as a new species.