Dietary competition between the alien Asian Musk Shrew (Suncus murinus) and a re-introduced population of Telfair's Skink (Leiolopisma telfairii).

Re-introduction of rare species to parts of their historical range is becoming increasingly important as a conservation strategy. Telfair's Skinks (Leiolopisma telfairii), once widespread on Mauritius, were until recently found only on Round Island. There it is vulnerable to stochastic events, including the introduction of alien predators that may either prey upon it or compete for food resources. Consequently, skinks have been introduced to Ile aux Aigrettes, another small Mauritian island that has been cleared of rats. However, the island has been invaded by Asian Musk Shrews (Suncus murinus), a commensal species spread by man well beyond its natural Asian range. Our aim was to use next-generation sequencing to analyse the diets of the shrews and skinks to look for niche competition. DNA was extracted from skink faeces and from the stomach contents of shrews. Application of shrew- and skink-specific primers revealed no mutual predation. The DNA was then amplified using general invertebrate primers with tags to identify individual predators, and then sequenced by 454 pyrosequencing. 119 prey MOTUs (molecular taxonomic units) were isolated, although none could be identified to species. Seeding of cladograms with known sequences allowed higher taxonomic assignments in some cases. Although most MOTUs were not shared by shrews and skinks, Pianka's niche overlap test showed significant prey overlap, suggesting potentially strong competition where food resources are limited. These results suggest that removal of the shrews from the island should remain a priority.

Measurement of direct photons in Au+Au collisions at √(s(NN))=200 GeV.

We report the measurement of direct photons at midrapidity in Au+Au collisions at √(s(NN))=200 GeV. The direct photon signal was extracted for the transverse momentum range of 4 GeV/c

First Report of Cylindrocladiella parva as a Grapevine Pathogen in New Zealand.

Isolates morphologically identified as Cylindrocladiella parva were isolated from characteristic black foot symptoms on a grapevine (Vitis vinifera) rooted on 101-14 rootstock from Central Otago in 2005 and 101-14 rootstocks from a nursery in the Auckland Region in 2007 and 2008. On potato dextrose agar, the isolates initially produced cottony, white mycelia that turned grayish cream or golden cream within 10 days, the initially tawny colony undersides becoming dark brown with age. Conidia (0 to 1 septate; 16.4 to 17.0 [16.7] × 2.3 to 2.6 [2.5] µm) and abundant chlamydospores were produced. To confirm identity of the isolates, genomic DNA was extracted and the ribosomal DNA (rDNA) and ß-tubulin gene were amplified and sequenced (3,4). Sequences of the PCR products were compared with sequences in GenBank. The rDNA (535 bp) and ß-tubulin (297 bp) sequences of the four isolates were 100 and 99% identical, respectively, to reported sequences of C. parva in GenBank (AY793454, grapevine isolate (4)/AY793455 for rDNA; AY793486/AY793488, grapevine isolate (4)/AY793489/HM034822 for ß-tubulin). Although C. parva was previously isolated from grapevines in New Zealand (2) and rootstocks of mature grapevines, cuttings, and graft unions of grafted young grapevines in South Africa (4), its role as a pathogen of Vitis spp. has not been confirmed (2,4). However, it has been reported as a pathogen of Eucalyptus spp. (1) and was also isolated from Telopea speciosissima and Macadamia integrifolia in New Zealand (2,4). The C. parva isolates were tested as a mixed inoculum (four isolates) for pathogenicity on roots of 10 grapevine rootstock plants each of cvs. 101-14 and Schwarzmann (Sch). The rootstocks were grown in potting mix for 4 months, after which the root systems of all vines were wounded with an asparagus knife with a sharp, square tip, driven vertically down into the soil at four equidistant locations approximately 8 cm from the trunk. Each plant was inoculated with 50 ml of the mixed-isolate conidial suspension (106/ml), or 50 ml water (controls), followed by 50 ml of water. After 7 months of growth, the plants were harvested. For C. parva-inoculated plants, internal blackening of the stem base tissue was observed. Isolations from surface-sterilized trunk bases recovered C. parva from four and nine plants of 101-14 and Sch, respectively, with C. parva infections in 25 and 48%, respectively, of the four wood pieces taken per plant. Plants inoculated with water had no blackening and no C. parva was isolated from their stem bases. Mean shoot dry weights of inoculated plants (17.9 and 15.0 g for 101-14 and Sch, respectively) were significantly lower (P = 0.035) than noninoculated controls (26.5 and 20.0 g for 101-14 and Sch, respectively). Mean root dry weights were reduced by C. parva inoculation, although not significantly (32.7 and 27.0 g for C. parva inoculated 101-14 and Sch, respectively, and 36.2 and 27.4 g for control 101-14 and Sch, respectively). To our knowledge, this is the first report of C. parva as a pathogen of grapevines (2,4) and suggests that along with Cylindrocarpon spp., C. parva is part of the pathogen complex responsible for black foot of grapevines. References: (1) P. W. Crous et al. Plant Pathol. 42:302, 1993. (2) P. D. Gadgil et al. Fungi on Trees and Shrubs in New Zealand. Fungal Diversity Press, Hong Kong, 2005. (3) N. L. Glass and G. C. Donaldson. Appl. Environ. Microbiol. 61:1323, 1995. (4) G. J. van Coller et al. Australas. Plant Pathol. 34:489, 2005.

First record of Neoxysomatium brevicaudatum through the non-invasive sampling of Anguis fragilis: complementary morphological and molecular detection.

Relatively few studies have examined the parasite fauna of British reptiles, partly due to the cryptic nature and low population density of these hosts. Here we examined 12 populations of the slow worm Anguis fragilis which, unlike other UK lizards, occurs at locally high population densities. Morphological examination of non-invasively collected faecal samples revealed the presence of Neoxysomatium brevicaudatum and a second unidentified nematode species. Although previously unrecorded from slow worms in the UK, N. brevicaudatum was present in 38% of animals (mean intensity 70.9, range 1-686). Morphological identification was confirmed by sequencing the 18S ribosomal gene. The use of the species-specific, cytochrome oxidase I mitochondrial gene primers proved an efficient alternative to conventional, microscope screening for parasites, although the original identification of N. brevicaudatum was dependent upon morphological characters. Sequencing also identified the second, smaller nematode as belonging to the Rhabdiasidae family: this species was even more common at a prevalence of 83% (mean intensity 102.8, range 1-2000). While increasing our knowledge of the UK macroparasite fauna, this work demonstrates the benefits of a combined morphological-molecular approach.

Enhanced production of direct photons in Au + Au collisions at square root(S(NN)) = 200 GeV and implications for the initial temperature.

The production of e+ e- pairs for m(e+ e-)<0.3 GeV/c2 and 1

Charged Kaon interferometric probes of space-time evolution in Au+Au collisions at sqrt[S(NN)]=200 GeV.

Bose-Einstein correlations of charged kaons are used to probe Au+Au collisions at sqrt[S(NN)]=200 GeV and are compared to charged pion probes, which have a larger hadronic scattering cross section. Three-dimensional Gaussian source radii are extracted, along with a one-dimensional kaon emission source function. The centrality dependences of the three Gaussian radii are well described by a single linear function of N(part)1/3 with a zero intercept. Imaging analysis shows a deviation from a Gaussian tail at r greater than or approximately equal to 10 fm, although the bulk emission at lower radius is well described by a Gaussian. The presence of a non-Gaussian tail in the kaon source reaffirms that the particle emission region in a heavy-ion collision is extended, and that similar measurements with pions are not solely due to the decay of long-lived resonances.

Overlapping platelets: a diffusion barrier in a teleost swimbladder.

Overlapping platelets are layered within the connective tissue of the wall of a closed (physoclistous) swimbladder. The close, staggered arrangement of the platelets is viewed as a physical barrier that can interfere with the diffusion pathway of gas molecules. The result is a more efficient retention of gas pressures within the swimbladder.

Competitive hydration of quinazoline at the montmorillonite-water interface.

Ultraviolet spectroscopic analyses of suspensions of quinazoline and Na(+)-saturated montmorillonite have indicated that covalent hydration of the monovalent organic cation is inhibited at or near the clay surface. A similar lack of hydration was observed in solutions of quinazoline and high-ionic-strength calcium chloride. The inhibition is attributed to a local competition between quinazoline and the inorganic cations for water of hydration.

Intra-specific variation in resting metabolic rate in MF1 mice is not associated with membrane lipid desaturation in the liver.

The 'membrane pacemaker' hypothesis provides a putative mechanistic linkage between variations in energy metabolism, rates of ageing and lifespan across different species. Within species we have found positive associations between longevity and metabolism, which contrast the inter-specific trends. It is of interest to know therefore how levels of lipid desaturation in membranes are linked to variation in metabolism between individuals within species. We explored this problem by extracting membrane fatty acids from the livers of mice that varied in their metabolic rate, in a strain (MF1) where we have previously demonstrated a positive association between metabolism and lifespan. We measured resting metabolic rate (RMR) in 60 mice, each measured on three occasions, and measured their body compositions using dual energy X-ray absorptiometry (DXA). We selected 28 individuals that exhibited a wide variation in their mean resting metabolic rates (RMR) and extracted membrane lipids from the livers of these mice post mortem and analysed them for the patterns of contribution of different fatty acids. We then sought associations between the levels of membrane desaturation and the individual variability in RMR, using the proportional contributions of each fatty acid as predictors in a stepwise regression or by re-describing the variation in fatty acyl lipids using a PCA analysis and then seeking associations between scores on the derived components and RMR. We used whole animal RMRs and also RMR with the effects of body composition (fat free mass) removed. The level of individual variation in RMR was consistent with our previous observations. There was a significant positive association (p=0.019) between the proportion of palmitic acid (16:0) in the membranes and RMR, which was strengthened (p=0.014) when we adjusted RMR for differences in fat free mass. The proportion of palmitic acid (16:0) explained 20.9% of the individual variation in residual RMR. There was no association between RMR or mass adjusted RMR and the proportional representation of any other fatty acid, including 22:6 (DHA) predicted by the membrane pacemaker hypothesis to be of particular significance. High levels of saturated fatty acids in the membranes of mice with high rates of metabolism may contribute to their greater longevity, but the mechanism tying together increased membrane saturation with elevated RMR remains unclear.

Elliptic flow for phi mesons and (anti)deuterons in Au+Au collisions at square root of sNN=200 GeV.

Differential elliptic flow (v(2)) for phi mesons and (anti)deuterons (d)d is measured for Au+Au collisions at square root of sNN=200 GeV. The v(2) for phi mesons follows the trend of lighter pi+/- and K+/- mesons, suggesting that ordinary hadrons interacting with standard hadronic cross sections are not the primary driver for elliptic flow development. The v(2) values for (d)d suggest that elliptic flow is additive for composite particles. This further validation of the universal scaling of v(2) per constituent quark for baryons and mesons suggests that partonic collectivity dominates the transverse expansion dynamics.

Emerging tools to study proteoglycan function during skeletal development.

In the past 20years, appreciation for the varied roles of proteoglycans (PGs), which are specific types of sugar-coated proteins, has increased dramatically. PGs in the extracellular matrix were long known to impart structural functions to many tissues, especially articular cartilage, which cushions bones and allows mobility at skeletal joints. Indeed, osteoarthritis is a debilitating disease associated with loss of PGs in articular cartilage. Today, however, PGs have a demonstrated role in cell biological processes, such as growth factor signalling, prompting new perspectives on the etiology of PG-associated diseases. Here, we review diseases associated with defects in PG synthesis and sulfation, also highlighting current understanding of the underlying genetics, biochemistry, and cell biology. Since most research has analyzed a class of PGs called heparan sulfate PGs, more attention is paid here to studies of chondroitin sulfate PGs (CSPGs), which are abundant in cartilage. Interestingly, CSPG synthesis is tightly linked to the cell biological processes of secretion and lysosomal degradation, suggesting that these systems may be linked genetically. Animal models of loss of CSPG function have revealed CSPGs to impact skeletal development. Specifically, our work from a mutagenesis screen in zebrafish led to the hypothesis that cartilage PGs normally delay the timing of endochondral ossification. Finally, we outline emerging approaches in zebrafish that may revolutionize the study of cartilage PG function, including transgenic methods and novel imaging techniques. Our recent work with X-ray fluorescent imaging, for example, enables direct correlation of PG function with PG-dependent biological processes.

Luminal and basolateral polyamine uptake by rat small intestine stimulated to grow by Phaseolus vulgaris lectin phytohaemagglutinin in vivo.

Luminal and basolateral uptake of polyamines by the rat small intestine was studied in vivo. In the concentration range studied (0.1-5 mg per rat) 23-47% of the individual polyamines given intragastrically were found in the body after 1 h, with the small intestine retaining 4-12% of the dose. With spermidine or spermine, labelled polyamines accounted for 85-96% of the counts in the small intestine and between 72-82% were in the form given. However, with putrescine only 29-39% of the label found in the tissue remained in polyamine form and even less, 11-15%, as putrescine. Luminal uptake of polyamines was linear, non-saturable and was not stimulated when small intestinal growth was stimulated by phytohaemagglutinin (PHA). On the basolateral side of the gut, polyamine uptake was stimulated by PHA in a time-dependent way in advance of detectable growth. Overall polyamine recoveries were high (89-99%) with intraperitoneally administered spermidine and spermine. Moreover, a large proportion of the counts in the tissue (63-89%) were still in the original form. Even with putrescine, total recoveries of polyamines (72-88%) and putrescine (24-33%) were elevated in comparison with those from the lumen. Treatment of rats with alpha-difluoromethylornithine (DFMO), an inhibitor of ornithine decarboxylase, reduced tissue polyamine content, although it had slight effects only on basolateral polyamine transport. The PHA-stimulated increase of polyamine uptake was not abolished in the presence of DFMO.

Potato lectin: a three-domain glycoprotein with novel hydroxyproline-containing sequences and sequence similarities to wheat-germ agglutinin.

Potato (Solanum tuberosum) tuber lectin is a chitin-binding, hydroxyproline-rich glycoprotein, which may be involved in the defence mechanism of the plant. We had previously obtained evidence that it consists of at least two very dissimilar domains. The aim was to use a combination of accurate determinations of molecular weight and protein sequencing to gain more accurate information on the domains. Accurate determinations of the molecular weight of the lectin by a MALDI mass spectrometer have shown that the subunit molecular weight is 65,500 (+/- 1100) and that of a totally deglycosylated sample is 31,250 (+/- 30). This means that the lectin is 52.3 (+/- 1)% carbohydrate with a considerable number of glycoforms being present. Partial sequences and other analyses are consistent with the existence of three distinct domains. These are: (1) an N-terminal region which is rich in proline but poor in hydroxyproline; (2) a glycosylated region with a glycosylated molecular weight of 45,300 (+/- 1100) and a deglycosylated molecular weight of 11,050 (+/- 50) which is extremely rich in glycosylated hydroxyproline residues with a similar sequence to extensins; and (3) a cystine-rich domain which has the sugar binding site shows partial conservation of a repeated motif common to many chitin-binding proteins of the hevin family including wheat-germ agglutinin. The closest similarity seems to be to the sequence of potato basic chitinase.

Synthesis, antinociceptive activity, and opioid receptor profiles of substituted trans-3-(decahydro- and octahydro-4a-isoquinolinyl)phenols.

A series of trans-3-(6- and 7-substituted-decahydro-4a-isoquinolinyl)phenols and trans-3-(octahydro-4a-isoquinolinyl)phenols have been synthesized as potential opioid analgesics. Using a combination of in vitro and in vivo test systems, the receptor profiles of selected compounds have been assessed and in some instances distinguish between mu- and kappa-receptor agonists. In general, introduction of a 6-exocyclic methylene group into the trans-3-(decahydro-4a-isoquinolinyl)phenol system enhanced both antinociceptive activity and kappa-opioid receptor selectivity. For each series, analogues bearing an N-cyclopropylmethyl substituent exhibited greater kappa-receptor selectivity while N-methyl derivatives showed greater mu-receptor selectivity. The 7-substituted compounds (3b) were significantly less potent antinociceptive agents than their 6-substituted counterparts (3a), the octahydroisoquinoline analogues exhibiting intermediate activity. The axial 8-methyl-6-exocyclic methylene isoquinoline (20) is the most potent compound in the mouse abdominal constriction assay (ED50 = 0.05 mg/kg sc), whereas the equatorial 8-methyl isomer (16) was significantly less potent (ED50 = 3.3 mg/kg sc).

New kappa-receptor agonists based upon a 2-[(alkylamino)methyl]piperidine nucleus.

The syntheses of some 1-[(3,4-dichlorophenyl)acetyl]-2- [(alkylamino)methyl]piperidines and their activities as kappa-opioid receptor agonists are described. Selected structural modifications are made to the basic moiety and at the 2-, 3-, 4-, 5-, and 6-positions on the piperidine nucleus to enable structure-activity relationships to be delineated. As a result, some highly potent and selective kappa-receptor agonists have been identified. In particular, this has been achieved by introduction of oxygen-containing functionality into the 4-position of the piperidine nucleus or the 3-position of the pyrrolidinylmethyl side chain. Thus, 1-[(3,4-dichlorophenyl)acetyl]- 2-[[1-(3-oxopyrrolidinyl)]methyl]piperidine (10) possesses high activity in the rabbit vas deferens (LVD, kappa-specific tissue) (IC50 = 0.20 nM) and is a potent antinociceptive agent, as determined by the mouse acetylcholine-induced abdominal constriction test (MAC) (ED50 = 0.06 mg/kg, sc). The spirocyclic analogue 8-[(3,4-dichlorophenyl)acetyl]-7-(1-pyrrolidinylmethyl)-1,4-dio xa-8- azaspirol4.5]decane (39) showed exceptionally potent activity: LVD, IC50 = 0.10 nM; MAC, ED50 = 0.001 mg/kg, sc. Both 10 and 39 displayed high selectivity for kappa-opioid receptors over both mu- and delta-opioid receptor subtypes.

Effect of the beta-adrenoceptor agonist clenbuterol and phytohaemagglutinin on growth, protein synthesis and polyamine metabolism of tissues of the rat.

1. The kidney bean lectin, phytohaemagglutinin (PHA), induced a marked atrophy of skeletal muscle which was evident from the changes in tissue composition (protein, RNA, DNA and polyamine content) and from the reduction in weight and protein synthesis of hind leg muscles of rats fed on kidney bean-diets for four days. The beta-adrenoceptor agonist, clenbuterol, induced skeletal muscle hypertrophy by transiently stimulating protein synthesis. As a consequence, the muscle loss caused by a short exposure to PHA was, in part, ameliorated by clenbuterol treatment. 2. Cardiac muscle was affected to a lesser extent than skeletal muscle by both clenbuterol and the lectin. However, there was evidence that protein synthesis in heart was reduced by PHA. 3. PHA had opposite effects on the gut, the lectin-induced hyperplasia of the jejunum was accompanied by a large increase in protein synthesis. Clenbuterol alone had no effect on the jejunum whereas a combination of PHA and clenbuterol appeared to exacerbate the effect of the lectin on gut. 4. Both the lectin-induced gut growth and the hypertrophy of skeletal muscle caused by clenbuterol were preceded by the accumulation of polyamines in the respective tissues. Of particular note was the observation that a significant increase in the proportion of the intraperitoneally injected 14C-labelled spermidine or putrescine taken up by the growing tissues could be detected by the second day. Therefore, the measurement of uptake of labelled polyamines may be used as a sensitive indicator of early alterations in tissue metabolism.

Switching between control and phytohaemagglutinin-containing diets affects growth of Krebs II ascites cells and produces differences in the levels of putrescine, spermidine and spermine.

Almost twice as many ascites tumour cells were recovered from mice pre-fed for 3 days on a lactalbumin (La)-based control diet, injected with Krebs II ascites cells and then maintained on the same diet for a further 8 days, when compared with mice fed on a phytohaemagglutinin-containing (PHA) diet for the whole period. A dietary switch on the day of injection of tumour cells produced an intermediate effect; mice switched to the La diet after pre-feeding on PHA for 3 days developed somewhat more tumour cells than when the opposite dietary switch was performed. The polyamine content in the tumour cells was lowest in the mice fed on La, and highest in mice fed PHA for the duration of the experiment, respectively. Since large amounts of extraneous polyamines are required in order to sustain tumour growth, and the hyperplastic growth of the gut which occurs in response to injesting the lectin is a polyamine-dependent process, it is evident that the two growth signals compete with one another for important nutrients/growth factors, including polyamines.

Intracellular levels of polyamines in Krebs II lymphosarcoma cells in mice fed phytohaemagglutinin-containing diets are coupled with altered tumour growth.

The number of Krebs II tumour cells recovered from the ascitic fluid of mice fed for 8 days on a lactalbumin (La) control diet was about three times higher than that in animals fed a phytohaemagglutinin-containing (PHA) diet. Feeding a PHA diet for less than 8 days after tumour cell injection also led to a reduction in tumour cell growth. There was an apparent inverse relationship between the total tumour cell count and the intracellular content of putrescine, spermidine and spermine. Hyperplasia of the small intestine occurred in the mice during the development of the ascites. A series of other organs were not affected in the same manner. The results indicate that the polyamine content of Krebs II ascites cells must increase by more than three-fold in order to achieve the intracellular concentration necessary to be able to enter the S-phase. A partial synchronization of the tumour cell population is suggested. Hyperplastic growth of the small intestine would appear to compete with tumour cells for polyamines from a common body pool.

Purified Pseudomonas aeruginosa PA-I lectin induces gut growth when orally ingested by rats.

The effects of PA-I lectin isolated from the human pathogen Pseudomonas aeruginosa upon cellular metabolism in vivo have been studied using the rat gut as a model system. Orally ingested PA-I lectin stimulated metabolic activity and induced polyamine accumulation and growth in the small intestine, caecum and colon. The nature and extent of the changes induced by PA-I lectin were similar to those caused by dietary kidney bean lectin and were likely to lead to impaired epithelial cell function and integrity. This finding contributes to our understanding of the possible roles of these lectins in Pseudomonas aeruginosa infection.

Salmonella typhimurium and Salmonella enteritidis induce gut growth and increase the polyamine content of the rat small intestine in vivo.

The effects of infection by Salmonella enteritidis and S. typhimurium on the small and large intestines, liver, spleen and mesenteric nodules of rats were studied in vivo. Both Salmonella serotypes persisted and proliferated in the gastrointestinal tract and invaded sub-epithelial tissues, mainly the ileum, leading to the systemic distribution of these pathogens. Coincidental with infection, the rate of crypt cell proliferation increased resulting in substantial growth of the small intestine. The extent of this and the accompanying accumulation of polyamines was particularly dramatic in the ileum where there was also some disruption of the villus epithelium. It is possible that these effects of the infection on the metabolism and morphology of the small bowel, which strongly resembled the changes induced by some plant lectins, may facilitate the colonisation and invasion of the gut by Salmonellae.