Canada lynx (Lynx canadensis) gene flow across a mountain transition zone in western North America

Mountain ecotones have the potential to cause multiple patterns in divergence, from simple barrier effects to more fundamental ecological divergence. Most work in mountain ecotones in North America has focused on reinforcement between refugial populations, making prediction of how mountains impact species that are not restricted to separate glacial refugia remains difficult. This study focused on the Canada lynx (Lynx canadensis Kerr, 1792), a highly mobile felid considered to be a habitat and dietary specialist. Specifically, we used 14 microsatellite loci and landscape genetic tools to investigate if the Rocky Mountains and associated climatic transitions influence lynx genetic differentiation in western North America. Although lynx exhibited high gene flow across the region, analyses detected structuring of neutral genetic variation across our study area. Gene flow for lynx most strongly related to temperature and elevation compared with other landscape variables (terrain roughness, percent forest cover, and habitat suitability index) and geographic distance alone. Overall, genetic structure in lynx is most consistent with barrier effects created by the Rocky Mountains rather than ecological divergence. Furthermore, warmer temperatures had a measurable impact on gene flow, which suggests connectivity may further decrease in peripheral or fragmented populations as climate warms.

Continent-wide effects of urbanization on bird and mammal genetic diversity

Urbanization and associated environmental changes are causing global declines in vertebrate populations. In general, population declines of the magnitudes now detected should lead to reduced effective population sizes for animals living in proximity to humans and disturbed lands. This is a cause for concern because effective population sizes set the rate of genetic diversity loss due to genetic drift, the rate of increase in inbreeding and the efficiency with which selection can act on beneficial alleles. We predicted that the effects of urbanization should decrease effective population size and genetic diversity, and increase population-level genetic differentiation. To test for such patterns, we repurposed and reanalysed publicly archived genetic datasets for North American birds and mammals. After filtering, we had usable raw genotype data from 85 studies and 41 023 individuals, sampled from 1008 locations spanning 41 mammal and 25 bird species. We used census-based urban-rural designations, human population density and the Human Footprint Index as measures of urbanization and habitat disturbance. As predicted, mammals sampled in more disturbed environments had lower effective population sizes and genetic diversity, and were more genetically differentiated from those in more natural environments. There were no consistent relationships detectable for birds. This suggests that, in general, mammal populations living near humans may have less capacity to respond adaptively to further environmental changes, and be more likely to suffer from effects of inbreeding.

In Vitro Evaluation of Novel Nitazoxanide Derivatives against Mycobacterium tuberculosis

Nitazoxanide has antiparasitic and antibiotic activities including activity against Mycobacterium tuberculosis. We prepared and evaluated a set of its analogues to determine the structure-activity relationship, and identified several amide- and urea-based analogues with low micromolar activity against M. tuberculosis in vitro. Pharmacokinetics in the rat suggested a path forward to obtain bioavailable compounds. The series had a good microbiological profile with bactericidal activity in vitro against replicating and nonreplicating M. tuberculosis. Analogues had limited activity against other Gram-positive bacteria but no activity against Gram-negative bacteria. Our studies identified the key liability in this series as cytotoxicity. Future work concentrating on identifying the target(s) could assist in removing activity against eukaryotic cells.

Synthesis and Evaluation of the 2-Aminothiazoles as Anti-Tubercular Agents

The 2-aminothiazole series has anti-bacterial activity against the important global pathogen Mycobacterium tuberculosis. We explored the nature of the activity by designing and synthesizing a large number of analogs and testing these for activity against M. tuberculosis, as well as eukaryotic cells. We determined that the C-2 position of the thiazole can accommodate a range of lipophilic substitutions, while both the C-4 position and the thiazole core are sensitive to change. The series has good activity against M. tuberculosis growth with sub-micromolar minimum inhibitory concentrations being achieved. A representative analog was selective for mycobacterial species over other bacteria and was rapidly bactericidal against replicating M. tuberculosis. The mode of action does not appear to involve iron chelation. We conclude that this series has potential for further development as novel anti-tubercular agents.

Isolation of peripheral populations of Canada lynx (Lynx canadensis)

Landscape barriers to gene flow, such as rivers, can affect animal populations by limiting the potential for rescue of these isolated populations. We tested the riverine barrier hypothesis, predicting that the St. Lawrence River in eastern Canada would cause genetic divergence of Canada lynx (Lynx canadensis Kerr, 1792) populations by restricting dispersal and gene flow. We sampled 558 lynx from eastern Canada and genotyped these at 14 microsatellite loci. We found three genetic clusters, defined by the St. Lawrence River and the Strait of Belle Isle, a waterway separating Newfoundland from mainland Canada. However, these waterways were not absolute barriers, as we found 24 individuals that appeared to have crossed them. Peripheral populations of lynx are threatened in parts of Canada and the USA, and it is thought that these populations are maintained by immigration from the core. Our findings suggest that in eastern North America, rescue might be less likely because the St. Lawrence River restricts dispersal. We found that ice cover was often sufficient to allow lynx to walk across the ice in winter. If lynx used ice bridges in winter, then climate warming could cause a reduction in the extent and longevity of river and sea ice, further isolating these peripheral lynx populations.

The Processing and Properties of γ-irradiated HDPE Granules

Granular high density polyethylene has been irradiated to relatively low doses prior to processing. The molecular weight was, at the lower doses, increased and the molecular weight distribution broadened with increasing dose. At the two highest doses an insoluble gel was introduced. These variously irradiated granules were processed by two routes, compression and injection molding, and selected structural features and mechanical properties ascertained. For all granule doses compression molded samples could be produced, with the plaque density decreasing with increasing granule dose. While the ductility of the moldings improved with increasing granule dose, the modulus and yield stress both declined as the density of the moldings decreased. Injection molded samples could only be prepared from granules free of gel. The density of the moldings depended on both granule dose and barrel temperature: in general, the density first increased then declined with increasing granule dose, an effect associated with preferred molecular orientation. The yield stress and modulus both appeared to correlate better with melt flow index rather than density, to infer that preferred molecular orientation is significant in injection moldings and can override the influence of density.

Textile Based Antennas

The increasing desire to internet the soldier on the battlefield requires a new approach to outfit the soldier with communications systems capable of operating in multiple frequency domains as shown in Table 1. Outfitting the soldier with multiple unwieldy antennas often results in the equipment being left behind, used improperly or broken. The ultimate in unobtrusive antennas is one that conforms to the body and does not interfere with the normal degrees of freedom of the soldier's uniform. Conformal antennas mounted on the body must take into account the electrical properties of the body, particularly at frequencies above 30 MHz. In addition, integration into the textile structure requires that the antenna be isolated from effects of clothing usage including clothing movement, wet operation, washing, and mechanical abrasion.

Providing nicotine dependence treatment to psychiatric inpatients: the views of Australian nurse managers

The prevalence of smoking in psychiatric settings remains high. This study aims to describe the views of nurse managers in psychiatric inpatient settings regarding the provision of nicotine dependence treatment, and whether there were associations between such views and the provision of nicotine dependence treatment. A cross-sectional survey was mailed to all public psychiatric inpatient units in New South Wales, Australia, for completion by nurse managers. Of the identified 131 service units, 123 completed questionnaires were returned (94%). Patient-related factors were considered to have a high level of influence on the provision of nicotine dependence treatment: patients requesting assistance to quit (58%), patients being receptive to interventions (52%), and patient health improving with quitting (45%). Units where the respondent reported that nicotine dependence treatment was as important as other roles were more likely to provide nicotine dependence treatment compared to units whose respondents did not hold this view (OR = 0.257, d.f. = 1, P < 0.01). While the results indicate strong support for the provision of nicotine dependence treatment, this support appears qualified by perceived patient readiness to quit, suggesting care is provided selectively rather than systematically. Positioning smoking as an addiction requiring treatment within a traditional curative approach may lead to a health service more conducive to the routine provision of nicotine dependence treatment.

Catalytic and ligand-binding characteristics of Plasmodium falciparum serine hydroxymethyltransferase

The plant-like, bifunctional dihydrofolate reductase-thymidylate synthase (DHFR-TS) from malaria parasites has been a good target for drug development. Dihydrofolate reductase (DHFR) is inhibited by clinically established antimalarials, pyrimethamine and cycloguanil. Thymidylate synthase (TS) is the target of potent experimental antimalarials such as 5-fluoroorotate and 1843U89. Another enzyme in folate recycling, serine hydroxymethyltransferase (SHMT), produces 5,10-methylenetetrahydrofolate which, in many cells, is required for the de novo, biosynthesis of thymidine and methionine. Thus, the biochemical characterization of malarial SHMT was of interest. The principle, active Plasmodium falciparum SHMT (PfSHMT) was expressed in E. coli and purified using an N-terminal histidine tag. Unlike the plant enzyme, but like the host enzyme, PfSHMT requires the cofactor pyridoxal 5'-phosphate for enzymatic activity. The substrate specificities for serine, tetrahydrofolate, and pyridoxal 5'-phosphate were comparable to those for SHMT from other organisms. Antifolates developed for DHFR and TS inhibited SHMT in the mid-micromolar range, offering insights into the binding preferences of SHMT but clearly leaving room for improved new inhibitors. As previously seen with P. falciparum DHFR-TS, PfSHMT bound its cognate mRNA but not control RNA for actin. RNA binding was not reversed with enzyme substrates. Unlike DHFR-TS, the SHMT RNA-protein interaction was not tight enough to inhibit translation. Another gene PF14_0534, previously proposed to code for an alternate mitochondrial SHMT, was also expressed in E. coli but found to be inactive. This protein, nor DHFR-TS, enhanced the catalytic activity of PfSHMT. The present results set the stage for developing specific, potent inhibitors of SHMT from P. falciparum.

Hybridization between escaped domestic and wild American mink (Neovison vison)

The release of domesticated organisms into natural populations may adversely affect these populations through predation, resource competition, and the introduction of disease. Additionally, the potential for hybridization between wild and domestic conspecifics is of great concern because it can alter the evolutionary integrity of the affected populations. Wild American mink (Neovison vison) populations may be threatened not only by competition for resources with domestic mink originating from farms, but by breeding with such escapees. Using 10 microsatellite loci, we genotyped mink from Ontario, Canada, sampled from two farms, two putatively mixed populations in regions surrounding the mink farms, and two wild populations with no recent history of mink farming. Using individual-based Bayesian population assignment, we identified four population clusters, including one wild, and three domestic populations. The latter were not clustered by farm but rather by distinct line-bred colour phases. Population clustering also identified domestic and hybrid mink in the free-ranging populations. Nearly two-thirds of the mink sampled in the two putatively mixed populations (78% and 43%) were either farm escapees or descendants of escapees. Principal components analysis of allele frequencies supported our Bayesian assignment results. The power of our assignment test was assessed using simulated hybrid genotypes which suggested that our overall correct classification rate was 96.2%. The overwhelming presence of domestic animals and their hybridization with mink in natural populations is of great concern for the future sustainability of wild mink populations.

Effectiveness of a baking soda toothpaste delivering calcium and phosphate in reducing dentinal hypersensitivity

OBJECTIVE

The purpose of this controlled clinical trial was to determine the effectiveness and safety of a single-phase dentifrice that delivers calcium, phosphate, and fluoride to the tooth surface (Arm & Hammer Enamel Care for Sensitive Teeth toothpaste, United Kingdom) in reducing dentinal hypersensitivity.

METHODS

Two-hundred and eight qualifying subjects were randomly assigned to either the Enamel Care dentifrice group or a control dentifrice group, and brushed twice daily with their assigned dentifrice for eight weeks. Pain/discomfort in response to a thermal stimulus was assessed at baseline, week 4, and week 8 using a Visual Analogue Scale (VAS; primary outcome variable) and the Schiff Thermal Sensitivity Scale (STSS; secondary outcome variable). After eight weeks, volunteers from the Enamel Care group were switched to the control dentifrice and participated in a second eight-week study to determine the degree of persistence of pain reduction.

RESULTS

Both groups had statistically significant VAS score reductions from baseline at weeks 4 and 8, with mean VAS scores in the Enamel Care group decreasing by 45.6% at week 4 and 61.1% at week 8 (p < 0.0001). Enamel Care was statistically significantly more effective than the control at weeks 4 and 8, with respective mean VAS reductions of 63% (p < 0.0001) and 33% (p = 0.0004) greater than the control. Consistent with the VAS score results, the Enamel Care group had respective statistically significant STSS score reductions of 77% and 58% greater than the control group (p < 0.0001). The reductions in dentinal hypersensitivity seen in the Enamel Care group at week 8 persisted for an additional eight weeks, during which the subjects discontinued use of Enamel Care and brushed with the control dentifrice.

CONCLUSION

Enamel Care for Sensitive Teeth toothpaste (United Kingdom) is an effective dentifrice for the management of dentinal hypersensitivity, and its efficacy persists for a least eight weeks following discontinued product use.

A multi-sample design for assessing the comedolytic activity of topical products

BACKGROUND

Facial comedolytic studies allow testing of a maximum of two products. The upper back provides a larger area with a more uniform distribution of microcomedones for comedolytic studies.

OBJECTIVE

To design a multi-sample method for assessing comedolytic activity of topical products on the back. The effect of season on product discrimination was also explored.

METHODS

Three cleansing formulations (products B, C and D), a negative water control and 0.025% Retin-A cream (positive control) were tested. Seven subjects were recruited in summer and nine in fall. Products were applied for 8 weeks, comedolysis was assessed by visually evaluating cyanoacrylate follicular biopsies taken at baseline and post-treatment.

RESULTS

In all data sets (summer, fall and combined), sites treated with Retin-A had a significantly lower number of microcomedones as compared to the negative water control. In addition, cleansers B and D showed a significant reduction from baseline in the fall and combined (summer and fall) data, but not in summer data alone indicating different responses to treatment during the year.

CONCLUSIONS

The design was sensitive enough to detect differences between cleansing formulations under normal washing conditions. Reduced sensitivity observed during summer suggests hot humid conditions may decrease the comedolytic performance of topical products.

A comparison of molecular typing methods for Moraxella catarrhalis

AIMS

Three molecular typing techniques were examined to determine which method was the most discriminatory in order to perform epidemiological typing of Moraxella catarrhalis.

METHODS AND RESULTS

Twenty-five Mor. catarrhalis isolates obtained from nasopharyngeal aspirates collected from Aboriginal and non-Aboriginal children were subjected to random amplified polymorphic DNA (RAPD) analysis, automated ribotyping and pulsed field gel electrophoresis (PFGE). RAPD analysis determined two Mor. catarrhalis types, automated ribotyping with PstI determined four Mor. catarrhalis ribogroups and PFGE analysis with NotI determined 21 pulse field groups within the 25 isolates examined.

CONCLUSIONS

Analysis of discrimination index and typeability demonstrated that PFGE is the most discriminatory method for typing Mor. catarrhalis.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study confirms that PFGE is the most appropriate molecular tool for the epidemiological study of Mor. catarrhalis.

Gas chromatography-mass spectrometry/mass spectrometry analysis to determine natural and post-administration levels of oestrogens in bovine serum and urine

A novel analytical approach has been developed and shown to be capable of detecting the isomers of oestradiol in the low ppt (pg mL(-1)) range in bovine serum and urine. Following extractive derivatisation the analytes were detected as their 3-pentafluorobenzoyl 17-trimethylsilyl ether derivatives by gas chromatography-mass spectrometry/mass spectrometry (GC-MS/MS), using electron capture negative ion chemical ionisation. The isomers of oestradiol were quantified in both blank and post-administration urine and serum samples, with a view to setting action/threshold levels for these compounds, to allow discrimination between normal samples and samples from animals treated with growth promoting ear implants. A non-parametric statistical assessment of the data resulted in proposed action levels (with a false positive probability of 1 in 1000) of 1.6 and 2.7 ng mL(-1) for 17alpha-oestradiol, in male and female urine, respectively, and 40 and 44 pg mL(-1) for 17beta-oestradiol, in male and female urine, respectively. An action level of 20 pg mL(-1) was proposed for 17alpha- and 17beta-oestradiol in male serum. In female serum the proposed action levels were 40 and 20 pg mL(-1) for 17alpha- and 17beta-oestradiol, respectively.

Information systems in food safety management

Information systems are concerned with data capture, storage, analysis and retrieval. In the context of food safety management they are vital to assist decision making in a short time frame, potentially allowing decisions to be made and practices to be actioned in real time. Databases with information on microorganisms pertinent to the identification of foodborne pathogens, response of microbial populations to the environment and characteristics of foods and processing conditions are the cornerstone of food safety management systems. Such databases find application in: Identifying pathogens in food at the genus or species level using applied systematics in automated ways. Identifying pathogens below the species level by molecular subtyping, an approach successfully applied in epidemiological investigations of foodborne disease and the basis for national surveillance programs. Predictive modelling software, such as the Pathogen Modeling Program and Growth Predictor (that took over the main functions of Food Micromodel) the raw data of which were combined as the genesis of an international web based searchable database (ComBase). Expert systems combining databases on microbial characteristics, food composition and processing information with the resulting "pattern match" indicating problems that may arise from changes in product formulation or processing conditions. Computer software packages to aid the practical application of HACCP and risk assessment and decision trees to bring logical sequences to establishing and modifying food safety management practices. In addition there are many other uses of information systems that benefit food safety more globally, including: Rapid dissemination of information on foodborne disease outbreaks via websites or list servers carrying commentary from many sources, including the press and interest groups, on the reasons for and consequences of foodborne disease incidents. Active surveillance networks allowing rapid dissemination of molecular subtyping information between public health agencies to detect foodborne outbreaks and limit the spread of human disease. Traceability of individual animals or crops from (or before) conception or germination to the consumer as an integral part of food supply chain management. Provision of high quality, online educational packages to food industry personnel otherwise precluded from access to such courses.

Cancer clinical trials available in the community setting: A 5-year analysis from 1999–2004

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Background: Less than 5% of newly diagnosed cancer patients are accrued into clinical trials. In the community setting, the lack of appropriate clinical trials is a major barrier. Our prospective study in 2004 determined that 58% of newly diagnosed adult cancer patients at our community-based cancer center didn’t have a clinical trial available appropriate for their disease stage. Among those with clinical trials, 23% were subsequently found to be ineligible (Go RS, et al. Cancer 2006, in press). However, the availability of clinical trials may vary from year to year. Methods: A retrospective study was conducted to determine what clinical trials were available for newly diagnosed adult cancer patients at our institution from June 1999-July 2004. The study also investigated the proportions of newly diagnosed patients who had a clinical trial available appropriate for type and stage of disease and patients accrued. Results: Over the 5-year period, 207 (82, 87, 99, 102, 117, years 1–5, respectively) trials were available. Most (50.7%) trials were for the following cancers: breast (15.5%), lung (13.5%), head and neck (7.7%), colorectal (7.2%) and lymphoma (6.8%). ECOG (53%), RTOG (26%), and CTSU (9%) provided the majority of the trials. A total of 5,776 new adult cancer patients were seen during this period. Overall, 60% of the patients had a trial available appropriate for type and stage of their cancer, but only 103 (3%) were enrolled. There was a significant upward trend in the proportions of patients with available trials over the years (60.2%, 55.9%, 59.2%, 60.7%, 63.9%, years 1–5, respectively; Mantel-Haenszel P=.008). The proportion of patients with a trial available was highest for prostate (97.3%), lung (90.9%), and breast (73.9%), and lowest for melanoma (17.1%), renal (11.6%), and bladder (7.2%). The majority of patients accrued to trials had the following cancers: breast (32%), lung (17%), lymphoma (9%), colon (7%), and prostate (5%). Conclusions: Nearly half of the newly diagnosed adult patients at our center had no trials available appropriate for type and stage of their cancers. It is likely that if strict clinical trial eligibility criteria were applied, approximately 2/3 of our patients would not be eligible for a clinical trial.

No significant financial relationships to disclose.

Regional scale evidence for improvements in surface water chemistry 1990-2001

The main aim of the international UNECE monitoring program ICP Waters under the Convention of Long-range Transboundary Air Pollution (CLRTAP) is to assess, on a regional basis, the degree and geographical extent of the impact of atmospheric pollution, in particular acidification, on surface waters. Regional trends are calculated for 12 geographical regions in Europe and North America, comprising 189 surface waters sites. From 1990-2001 sulphate concentrations decreased in all but one of the investigated regions. Nitrate increased in only one region, and decreased in three North American regions. Improvements in alkalinity and pH are widely observed. Results from the ICP Waters programme clearly show widespread improvement in surface water acid-base chemistry, in response to emissions controls programs and decreasing acidic deposition. Limited site-specific biological data suggest that continued improvement in the chemical status of acid-sensitive lakes and streams will lead to biological recovery in the future.

Lack of burning and stinging from a novel first-aid formulation applied to experimental wounds

Antiseptic-anesthetic first aid formulations typically produce a burning or stinging sensation when used on wounds. The aim of this study was to assess the lack of sting/burn potential of a prototype first-aid wipe when applied to superficial wounds. This was a one-day, double-blind, randomized study, evaluating the stinging/burning sensation from a prototype first-aid wipe with a cellulose base containing 1.0% pramoxine HCL and 0.13% benzalkonium chloride. The study followed a direct comparison test design of four test formulations. The remaining three articles were: (a) sterile 0.9% sodium chloride (no-sting/no-burn control), (b) 3% hydrogen peroxide (first-aid sting/burn control), and (c) 70% isopropyl alcohol (second sting/burn control). The test was performed on 24 subjects. The tape stripping method was used to create four standardized wounds on the volar forearms, reaching the glistening layer. Each test article was applied to the wound for 15 seconds. The subjects were asked to report the intensity of the stinging/burning sensation during the application. The prototype pramoxine-benzalkonium chloride wipe produced significantly less stinging/burning than both 70% isopropyl alcohol and 3% hydrogen peroxide. Also, the prototype wipe did not produce more stinging and burning in superficial wounds compared to the saline control.

The current status of nurse prescribing in dermatology

This review describes the current status of prescribing by nurses and other nonmedical staff in the UK with particular emphasis on issues affecting secondary care dermatology departments. We discuss background issues of how the process has evolved, the requirement for this initiative and its assessment, the terminology applied to different groups of prescribers, and training issues.

Optimisation of one-tube PCR-ELISA to detect femtogram amounts of genomic DNA

A simple, high-throughput, low-cost polymerase chain reaction-enzyme linked immunosorbent assay (PCR-ELISA) protocol that detects the presence of 4 fg of DNA from four bacterial fish pathogens Yersinia ruckeri, Tenacibaculum maritimum (formerly Flexibacter maritimus), Lactococcus garvieae and Aeromonas salmonicida was developed. DNA amplification was undertaken in a biphasic system with free and bound PCR that are achieved in the one NucleoLink tube. Solid-phase amplicons were detected using biotin labelled hybridization probes and visualised colourimetrically with streptavidin-alkaline phosphatase and p-nitrophenylphosphate as substrate. PCR and hybridization took less than 8 h to perform with maximum signal output for femtogram amounts of template DNA achieved within 24 h. Implementation and optimization of the protocol is discussed.

Hordoindolines are associated with a major endosperm-texture QTL in barley (Hordeum vulgare)

Endosperm texture has a tremendous impact on the end-use quality of wheat (Triticum aestivum L.). Cultivars of barley (Hordeum vulgare L.), a close relative of wheat, also vary measurably in grain hardness. However, in contrast to wheat, little is known about the genetic control of barley grain hardness. Puroindolines are endosperm-specific proteins found in wheat and its relatives. In wheat, puroindoline sequence variation controls the majority of wheat grain texture variation. Hordoindolines, the puroindoline homologs of barley, have been identified and mapped. Recently, substantial allelic variation was found for hordoindolines among commercial barley cultivars. Our objective was to determine the influence of hordoindoline allelic variation upon grain hardness and dry matter digestibility in the 'Steptoe' x 'Morex' mapping population. This population is segregating for hordoindoline allele type, which was measured by a HinA/HinB/Gsp composite marker. One-hundred and fifty lines of the 'Steptoe' x 'Morex' population were grown in a replicated field trial. Grain hardness was estimated by near-infrared reflectance (NIR) and measured using the single kernel characterization system (SKCS). Variation attributable to the HinA/HinB/Gsp locus averaged 5.7 SKCS hardness units (SKCS U). QTL analysis revealed the presence of several areas of the genome associated with grain hardness. The largest QTL mapped to the HinA/HinB/Gsp region on the short arm of chomosome 7 (5H). This QTL explains 22% of the SKCS hardness difference observed in this study. The results indicate that the Hardness locus is present in barley and implicates the hordoindolines in endosperm texture control.

Sphingomonas alaskensis strain AFO1, an abundant oligotrophic ultramicrobacterium from the North Pacific

Numerous studies have established the importance of picoplankton (microorganisms of < or =2 microm in length) in energy flow and nutrient cycling in marine oligotrophic environments, and significant effort has been directed at identifying and isolating heterotrophic picoplankton from the world's oceans. Using a method of diluting natural seawater to extinction followed by monthly subculturing for 12 months, a bacterium was isolated that was able to form colonies on solid medium. The strain was isolated from a 10(5) dilution of seawater where the standing bacterial count was 3.1 x 10(5) cells ml(-1). This indicated that the isolate was representative of the most abundant bacteria at the sampling site, 1.5 km from Cape Muroto, Japan. The bacterium was characterized and found to be ultramicrosized (less than 0.1 microm(3)), and the size varied to only a small degree when the cells were starved or grown in rich media. A detailed molecular (16S rRNA sequence, DNA-DNA hybridization, G+C mol%, genome size), chemotaxonomic (lipid analysis, morphology), and physiological (resistance to hydrogen peroxide, heat, and ethanol) characterization of the bacterium revealed that it was a strain of Sphingomonas alaskensis. The type strain, RB2256, was previously isolated from Resurrection Bay, Alaska, and similar isolates have been obtained from the North Sea. The isolation of this species over an extended period, its high abundance at the time of sampling, and its geographical distribution indicate that it has the capacity to proliferate in ocean waters and is therefore likely to be an important contributor in terms of biomass and nutrient cycling in marine environments.

Role of PHABULOSA and PHAVOLUTA in determining radial patterning in shoots

The upper side of the angiosperm leaf is specialized for efficient capture of sunlight whereas the lower side is specialized for gas exchange. In Arabidopsis, the establishment of polarity in the leaf probably requires the generation and perception of positional information along the radial (adaxial versus abaxial or central versus peripheral) dimension of the plant. This is because the future upper (adaxial) side of the leaf develops from cells closer to the centre of the shoot, whereas the future under (abaxial) side develops from cells located more peripherally. Here we implicate the Arabidopsis PHABULOSA and PHAVOLUTA genes in the perception of radial positional information in the leaf primordium. Dominant phabulosa (phb) and phavoluta (phv) mutations cause a dramatic transformation of abaxial leaf fates into adaxial leaf fates. They do so by altering the predicted sterol/lipid-binding domains of ATHB14 and ATHB9, proteins of previously unknown function that also contain DNA-binding motifs. This change probably renders the protein constitutively active, implicating this domain as a central regulator of protein function and the PHB and PHV proteins as receptors for an adaxializing signal.

Analysis of small amines in pharmaceuticals by capillary ion electrophoresis with conductivity detection

Capillary ion electrophoresis (CIE) with direct conductivity detection is a simple, fast, and versatile method for analysis of ions. In this study CIE with conductivity detection was used to analyze for hydroxylamine which is often used in the synthesis of pharmaceutical intermediates and drug substances. The conductivity response of hydroxylamine was investigated by using different buffer types and buffer concentrations. Other small amines were also studied with this method and were correlated with the molecular weight of the amines. The response of hydroxylamine increased significantly with MES glycylglycine buffer as compared to MES-histidine buffer (LOD from 10 to 1 ppm). The detection of trace level of hydroxylamine in a drug substance proved to be possible with this method. The developed method was also tested for the linearity range, reproducibility, and selectivity with several small amines. The method developed in this study was demonstrated as a sensitive and reliable method for detection and quantification of small amines in pharmaceutical substances.

Human infection with Halomonas venusta following fish bite

Halomonas venusta, a moderately halophilic, nonfermentative gram-negative rod, is reported for the first time as a human pathogen in a wound that originated from a fish bite.

Nurse prescribing in a day-care dermatology unit

A study carried out in an NHS trust showed that its dermatology nurses could safely undertake nurse prescribing. To be effective a formal system of nurse prescribing is required. This involves the compilation of a formulary for the nurse prescribers and the development of relevant treatment protocols. The introduction of nurse prescribing in a day-care unit led to improvements in the dermatology services available to the local population.