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Selected AbstractsBiochemical characterization of rice trehalose-6-phosphate phosphatases supports distinctive functions of these plant enzymesFEBS JOURNAL, Issue 5 2007Shuhei Shima Substantial levels of trehalose accumulate in bacteria, fungi, and invertebrates, where it serves as a storage carbohydrate or as a protectant against environmental stresses. In higher plants, trehalose is detected at fairly low levels; therefore, a regulatory or signaling function has been proposed for this molecule. In many organisms, trehalose-6-phosphate phosphatase is the enzyme governing the final step of trehalose biosynthesis. Here we report that OsTPP1 and OsTPP2 are the two major trehalose-6-phosphate phosphatase genes expressed in vegetative tissues of rice. Similar to results obtained from our previous OsTPP1 study, complementation analysis of a yeast trehalose-6-phosphate phosphatase mutant and activity measurement of the recombinant protein demonstrated that OsTPP2 encodes a functional trehalose-6-phosphate phosphatase enzyme. OsTPP2 expression is transiently induced in response to chilling and other abiotic stresses. Enzymatic characterization of recombinant OsTPP1 and OsTPP2 revealed stringent substrate specificity for trehalose 6-phosphate and about 10 times lower Km values for trehalose 6-phosphate as compared with trehalose-6-phosphate phosphatase enzymes from microorganisms. OsTPP1 and OsTPP2 also clearly contrasted with microbial enzymes, in that they are generally unstable, almost completely losing activity when subjected to heat treatment at 50 °C for 4 min. These characteristics of rice trehalose-6-phosphate phosphatase enzymes are consistent with very low cellular substrate concentration and tightly regulated gene expression. These data also support a plant-specific function of trehalose biosynthesis in response to environmental stresses. [source] Genetic variability in environmental isolates of Legionella pneumophila from Comunidad Valenciana (Spain)ENVIRONMENTAL MICROBIOLOGY, Issue 6 2006Mireia Coscollá Summary Legionella pneumophila is associated to recurrent outbreaks in several Comunidad Valenciana (Spain) localities, especially in Alcoi, where social and climatic conditions seem to provide an excellent environment for bacterial growth. We have analysed the nucleotide sequences of three loci from 25 environmental isolates from Alcoi and nearby locations sampled over 3 years. The analysis of these isolates has revealed a substantial level of genetic variation, with consistent patterns of variability across loci, and comparable to that found in a large, European-wide sampling of clinical isolates. Among the tree loci studied, fliC showed the highest level of nucleotide diversity. The analysis of isolates sampled in different years revealed a clear differentiation, with samples from 2001 being significantly distinct from those obtained in 2002 and 2003. Furthermore, although linkage disequilibrium measures indicate a clonal nature for population structure in this sample, the presence of some recombination events cannot be ruled out. [source] EPUAP classification system for pressure ulcers: European reliability studyJOURNAL OF ADVANCED NURSING, Issue 6 2007Dimitri Beeckman Abstract Title.,EPUAP classification system for pressure ulcers: European reliability study Aim., This paper is a report of a study of the inter-observer reliability of the European Pressure Ulcer Advisory Panel pressure ulcer classification system and of the differential diagnosis between moisture lesions and pressure ulcers. Background., Pressure ulcer classification is a valuable tool to provide a common description of ulcer severity for the purposes of clinical practice, audit and research. Despite everyday use of the European Pressure Ulcer Advisory Panel system, its reliability has been evaluated in only a limited number of studies. Methods., A survey was carried out between September 2005 and February 2006 with a convenience sample of 1452 nurses from five European countries. Respondents classified 20 validated photographs as normal skin, blanchable erythema, pressure ulcers (four grades), moisture lesion or combined lesion. The nurses were familiar with the use of the European Pressure Ulcer Advisory Panel classification scale. Results., Pressure ulcers were often classified erroneously (, = 0·33) and only a minority of nurses reached a substantial level of agreement. Grade 3 lesions were regularly classified as grade 2. Non-blanchable erythema was frequently assessed incorrectly as blanchable erythema. Furthermore, the differential diagnosis between moisture lesions and pressure ulcers appeared to be complicated. Conclusion., Inter-observer reliability of the European Pressure Ulcer Advisory Panel classification system was low. Evaluation thus needs to focus on both the clarity and complexity of the system. Definitions and unambiguous descriptions of pressure ulcer grades and the distinction between moisture lesions will probably enhance clarity. To simplify the current classification system, a reduction in the number of grades is suggested. [source] Bipolar gene flow in deep-sea benthic foraminiferaMOLECULAR ECOLOGY, Issue 19 2007J. PAWLOWSKI Abstract Despite its often featureless appearance, the deep-ocean floor includes some of the most diverse habitats on Earth. However, the accurate assessment of global deep-sea diversity is impeded by a paucity of data on the geographical ranges of bottom-dwelling species, particularly at the genetic level. Here, we present molecular evidence for exceptionally wide distribution of benthic foraminifera, which constitute the major part of deep-sea meiofauna. Our analyses of nuclear ribosomal RNA genes revealed high genetic similarity between Arctic and Antarctic populations of three common deep-sea foraminiferal species (Epistominella exigua, Cibicides wuellerstorfi and Oridorsalis umbonatus), separated by distances of up to 17 000 km. Our results contrast with the substantial level of cryptic diversity usually revealed by molecular studies, of shallow-water benthic and planktonic marine organisms. The very broad ranges of the deep-sea foraminifera that we examined support the hypothesis of global distribution of small eukaryotes and suggest that deep-sea biodiversity may be more modest at global scales than present estimates suggest. [source] Latest news and product developmentsPRESCRIBER, Issue 9 2007Article first published online: 3 SEP 200 Clinical trials flatter anti-TNFs in RA The efficacy of anti-TNF agents in clinical trials is not matched by experience in daily practice in patients with rheumatoid arthritis, say Dutch investigators (Ann Rheum Dis online: 10 April 2007; doi:10.1136/ard.2007.072447). They compared outcomes from a systematic review of trials of etanercept (Enbrel), infliximab (Remicade) and adalimumab (Humira) and a national postmarketing surveillance scheme (DREAM). In 5 of 11 comparisons, the response rate in DREAM was significantly lower than that in RCTs. Responses among DREAM patients who met the inclusion criteria for clinical trials were significantly greater than among noneligible patients and comparable with those of patients participating in the trials. The authors conclude that patients in trials have more severe disease and therefore a response to treatment that is not matched in daily practice. Methadone prescriptions double in 10 years Methadone treatment for opiate addicts has more than doubled in the past 10 years, according to an audit of opiate substitution in England by the National Treatment Agency for Substance Misuse (www.nta.nhs.uk). The total number of methadone prescriptions increased from 970 900 in 1995 to over 1.8 million in 2004. The introduction of buprenorphine (Subutex) has not reduced methadone prescribing , 96 per cent of responding centres prescribed methadone and 88 per cent prescribed buprenorphine. Seventy-two per cent of centres prescribe benzodiazepines to opiate addicts, causing the NTA some concern. GPs were involved in prescribing management in about 60 per cent of centres. Next NICE guidelines The Department of Health has referred eight topics to NICE for the development of clinical guidelines: preventing venous thromboembolism, acute coronary syndromes, chest pain, social complications during pregnancy (eg drug misuse), benign prostatic hyperplasia, constipation in children, neonatal jaundice and metastatic disease of unknown primary origin. Errors with children , Every step of drug treatment for children, from prescribing to writing notes, is associated with a substantial level of error, say US investigators (Quality and Safety in Health Care 2007;16:116-26). Their systematic review of 31 studies reporting medication errors in paediatrics found that 3-37 per cent were associated with prescribing errors, 5-58 per cent with dispensing errors, 72-75 per cent with errors of administration, and 17-21 per cent with documentation errors. Suggestions for remedial strategies were not evidence based, the authors found. , and transplant patients Errors in medication are common among outpatients who have received liver, kidney or pancreas transplants, a second US study has found (Arch Surg 2007;142:278-83). Twelve months' follow-up of 93 patients revealed a total of 149 errors of drug treatment, with a frequency of 15 in 219 visits over a four-week period. One-third of errors were associated with adverse events including hospital admission and graft rejection. Patients were taking an average of 11 medicines; analysis showed that over half of errors originated with the patients and 13 per cent were associated with prescribing. Paracetamol pack benefit challenged A new study has challenged accepted wisdom that reducing the OTC pack size of paracetamol cut the suicide rate (PLoS Medicine 2007;4:e105). In 1998, pack sizes of paracetamol were limited to 16 in general sale outlets and 32 in pharmacies. Suicide rates subsequently decreased but, though widely assumed, a causal link has not been established. Researchers from London and the Office of National Statistics have now examined mortality trends from suicide associated with antidepressants, aspirin, compound paracetamol preparations and nondrug poisoning. They found that all fatal suicides declined at similar rates after the pack size reductions. While not excluding the possibility that restricting easy access to paracetamol may have helped, these data suggest that other factors were also important. CV risk with ibuprofen among aspirin users Ibuprofen, but not naproxen, is associated with a higher risk of cardiovascular events and heart failure than lumiracoxib (Prexige) in high-risk patients, according to a new analysis of the TARGET trial (Ann Rheum Dis online: 5 April 2007; doi:10.1136/ard.2006.066001). TARGET comprised two studies comparing naproxen or ibuprofen with lumiracoxib in a total of 18 325 patients with OA. This post-hoc analysis stratified patients by their cardiovascular risk; the primary end-point was a composite of cardiovascular mortality, nonfatal myocardial infarction and stroke at one year. Among those at high risk who were taking aspirin, ibuprofen was associated with an increased risk of the composite end-point compared with lumiracoxib (2.14 vs 0.25 per cent). The risk was similar for naproxen and lumiracoxib (1.58 vs 1.48 per cent). In high-risk patients not taking aspirin, the risk was similar for ibuprofen and lumiracoxib, but lower for naproxen than lumiracoxib. Congestive heart failure was more common in patients taking ibuprofen than lumiracoxib (1.28 vs 0.14 per cent); the risk was similar with naproxen and lumiracoxib. The authors emphasise that their findings should be considered hypothesis-generating. CVD guidelines criticised The second edition of the guidelines of the Joint British Societies on preventing cardiovascular disease have been harshly criticised for failing to meet international quality standards (Int J Clin Pract online doi: 10.1111/j.1742-1241.2007.01310.x). Kent GP Dr Rubin Minhas evaluated the guidelines against the criteria of the Appraisal of Guidelines and Research (AGREE) Collaboration. He identified areas of weakness including stakeholder involvement, rigour of development, applicability (by not considering cost) and editorial independence from the pharmaceutical industry. The guidelines should not be recommended for clinical practice, he concludes. OTC naproxen? The MHRA is consulting on switching naproxen 250mg to pharmacy-only status for the treatment of period pain in women aged 15-50. The change would offer an alternative to ibuprofen, currently the only other OTC medicine with this indication. Responses should be submitted by 23 May. The Agency is currently considering responses to its consultation on switching tranexamic acid to OTC status for heavy menstrual bleeding. Diabetes costs The total cost of prescribing for diabetes in England has doubled in only five years, official statistics show. The NHS Information Centre (www.ic.nhs.uk) report shows that spending in primary and secondary care in 2006 was £561 million, up 14 per cent on 2005. Growth was due to increased prescribing of oral hypoglycaemic agents (notably the glitazones , up by one-third over 2005) and the higher costs of insulins. Pharmacists may give flu jabs PCTs may consider using pharmacists to administer flu vaccines to some at-risk groups in the 2007/08 season, according to Department of Health plans. Flu vaccination payment for patients with diabetes, coronary heart disease, and stroke and TIA is provided under the Quality Outcomes Framework. The Department suggests that PCTs consider contracting a local enhanced service from pharmacists to reach other patients at increased risk, such as those with chronic liver disease, multiple sclerosis and related conditions, hereditary and degenerative disease of the CNS and carers. Copyright © 2007 Wiley Interface Ltd [source] Investigation and correction of the gene-derived sequence of glutenin subunit 1Dx2 by matrix-assisted laser desorption/ionisation mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 20 2002Vincenzo Cunsolo Direct matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOFMS) analysis of a mixture of tryptic peptides was used to verify the gene-derived amino acid sequence of the high molecular weight (HMW) subunit 1Dx2 of bread wheat. Analysis of the digest was performed by recording several MALDI mass spectra of the mixture at low, medium and high mass ranges, and optimising the matrix and the acquisition parameters for each mass range. This resulted in coverage of the whole sequence except for a short fragment T3 (3 amino acids), which was not detected. It also allowed the insertion of a Pro residue in position 59 to be identified. The results obtained provide evidence for the lack of a substantial level of glycosylation or other post-translational modifications of subunit 1Dx2, and demonstrate that MALDI-MS is the most useful method presently available for the direct verification of the gene-derived sequences of HMW glutenin subunits and similar proteins. Copyright © 2002 John Wiley & Sons, Ltd. [source] Not by Twins Alone: Using the Extended Family Design to Investigate Genetic Influence on Political BeliefsAMERICAN JOURNAL OF POLITICAL SCIENCE, Issue 3 2010Peter K. Hatemi Variance components estimates of political and social attitudes suggest a substantial level of genetic influence, but the results have been challenged because they rely on data from twins only. In this analysis, we include responses from parents and nontwin full siblings of twins, account for measurement error by using a panel design, and estimate genetic and environmental variance by maximum-likelihood structural equation modeling. By doing so, we address the central concerns of critics, including that the twin-only design offers no verification of either the equal environments or random mating assumptions. Moving beyond the twin-only design leads to the conclusion that for most political and social attitudes, genetic influences account for an even greater proportion of individual differences than reported by studies using more limited data and more elementary estimation techniques. These findings make it increasingly difficult to deny that,however indirectly,genetics plays a role in the formation of political and social attitudes. [source] Informing policy for the Australian context , Costs, outcomes and cost savings of prenatal carrier screening for cystic fibrosisAUSTRALIAN AND NEW ZEALAND JOURNAL OF OBSTETRICS AND GYNAECOLOGY, Issue 1 2010Susannah MAXWELL Aims:, To examine the costs, outcomes and cost savings of three models of prenatal cystic fibrosis (CF) carrier screening compared to no screening from a public health sector perspective. Methods:, A decision tree was generated to estimate costs and outcomes for each screening model for a hypothetical cohort of 38 000 pregnancies. Sensitivity analysis assessed the impact of model parameter variation. Results:, Under baseline assumptions, the initial annual cost to provide a prenatal CF carrier-screening programme is Au$5.32 million, Au$3.35 million and $2.93 million for one-step, two-step simultaneous and two-step sequential screening respectively. Annual costs are significantly lower for an established programme. No screening model provides a net saving over a lifetime horizon; however, the results were sensitive to variation in lifetime cost of care, screening test costs and number of pregnancies per carrier couple. Conclusions:, Under some scenarios, prenatal CF carrier screening is cost saving to the health system; however, this is not conclusive and depends on several factors. Cost remains a potential barrier due to the substantial level of funding required in the short term. Feasibility and psychosocial, ethical and legal implications of screening need to be considered. Additionally, consultation is required with the Australian community on the acceptability and/or desire for prenatal CF carrier screening. [source] A NEW METHOD FOR STUDYING THE EXTENT, STABILITY, AND PREDICTORS OF INDIVIDUAL SPECIALIZATION IN VIOLENCE,CRIMINOLOGY, Issue 2 2007D. WAYNE OSGOOD Specialization in violence is an important scientific and policy topic, and over the past several decades, many analysis techniques for studying specialization have emerged. Research in this area continues to be hampered, however, by remaining methodological problems. To overcome these problems, we propose a new method for studying specialization in violence based on an item-response theory measurement approach that is implemented through a multilevel regression model. Our approach defines specialization as an individual level latent variable, takes into account the inherent confounds between specialization and overall level of offending, and gauges specialization relative to the population base rates of each offense. Our method also enables researchers to 1) estimate the extent and statistical significance of specialization, 2) assess the stability of specialization over time, and 3) relate specialization to explanatory variables. Using data from three studies, we found substantial levels of specialization in violence, considerable stability in specialization over time, and several significant and relatively consistent relationships of specialization to explanatory variables such as gender, parental education, and risk-seeking. [source] Determinants of within- and among-clutch variation in levels of maternal hormones in Black-Headed Gull eggsFUNCTIONAL ECOLOGY, Issue 3 2002Groothuis T. G. Summary 1.,Females of egg-laying vertebrates may adjust the development of their offspring to prevailing environmental conditions by regulating the deposition of hormones into their eggs. Within- and amng-clutch variation in levels of steroid hormones were studied in the egg yolks of the Black-Headed Gull (Larus ridibundus, Linnaeus) in relation to environmental conditions at the nest site. This species breeds in colonies of different densities and in different habitats, and the chicks hatch asynchronously. 2.,Egg yolks contained very high levels of androstenedione, substantial levels of testosterone and moderate levels of 5,-dihydrotestosterone. Oestrogen (17,-oestradiol) was not detected. 3.,Androgen levels increased strongly with laying order, irrespective of egg or yolk mass. This may compensate for the disadvantages of the later hatching chicks. These results have implications for adaptive hypotheses that were proposed for asynchronous incubation. 4.,Eggs of lighter clutches contained more androgens, perhaps to compensate for a lower nutritional quality of these eggs. 5.,Birds breeding in the periphery of a colony, being relatively more aggressive and having relatively large territories, laid eggs that contained more androgens than those of birds breeding in the centre. These high yolk androgen levels may facilitate growth and motor development of the chicks, which may be especially important for chicks developing at the periphery of a colony. Reduced levels may be adaptive for birds breeding in the centre, where risk of infectious diseases is high, since steroids may be immunosuppressive. 6.,Corrected for nest distance, clutches of birds in high vegetation, where predation risk is less severe and therefore competition for nest sites perhaps high, contained relatively high levels of androgens. It is suggested that the level of yolk androgens reflects the hormonal condition of the female, that in turn is influenced by her characteristics such as her age and aggressiveness, and the level of social stimulation. [source] Aerobic degradation by white-rot fungi of trichloroethylene (TCE) and mixtures of TCE and perchloroethylene (PCE)JOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 9 2008Ernest Marco-Urrea Abstract BACKGROUND: Trichloroethylene (TCE) and perchloroethylene (PCE) are considered among the most important groundwater pollutants around the world. These compounds are usually found together in polluted environments but little is known about the ability of microorganisms to simultaneously degrade TCE and PCE. RESULTS: Data showed that several species of white-rot fungi, including Trametes versicolor, Ganoderma lucidum, and Irpex lacteus, degrade substantial levels of TCE in pure culture. T. versicolor was chosen for further study since it degraded higher levels of TCE than the other organisms. Initial glucose concentration and reoxygenation of samples increased the amount of TCE dechlorination, but no significant difference in percentage TCE degradation was observed. T. versicolor was able to degrade 34.1 and 47.7% of PCE and TCE added as mixtures (containing 5 and 10 mg L,1, respectively). CONCLUSIONS: The degradation ability of TCE was extended to other species of white-rot fungi. Percentage degradation as well as chloride release from mixtures of TCE and PCE showed that T. versicolor degrades mixtures of TCE and PCE almost as well as its ability to degrade individually added TCE or PCE. The results suggest the potential promise of T. versicolor for bioremediation of TCE and PCE in the environment. Copyright © 2008 Society of Chemical Industry [source] Testing for microevolution in body size in three blue tit populationsJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 4 2004A. Charmantier Abstract Quantifying the genetic variation and selection acting on phenotypes is a prerequisite for understanding microevolutionary processes. Surprisingly, long-term comparisons across conspecific populations exposed to different environments are still lacking, hampering evolutionary studies of population differentiation in natural conditions. Here, we present analyses of additive genetic variation and selection using two body-size traits in three blue tit (Parus caeruleus) populations from distinct habitats. Chick tarsus length and body mass at fledging showed substantial levels of genetic variation in the three populations. Estimated heritabilities of body mass increased with habitat quality. The poorer habitats showed weak positive selection on tarsus length, and strong positive selection on body mass, but there was no significant selection on either trait in the good habitat. However, there was no evidence of any microevolutionary response to selection in any population during the study periods. Potential explanations for this absence of a response to selection are discussed, including the effects of spatial heterogeneity associated with gene flow between habitats. [source] Maturation-Dependent Alcohol Resistance in the Developing Mouse: Cerebellar Neuronal Loss and Gene Expression During Alcohol-Vulnerable and -Resistant PeriodsALCOHOLISM, Issue 8 2008Bahri Karaçay Background:, Alcohol abuse during pregnancy injures the fetal brain. One of alcohol's most important neuroteratogenic effects is neuronal loss. Rat models have shown that the cerebellum becomes less vulnerable to alcohol-induced neuronal death as it matures. We determined if maturation-dependent alcohol resistance occurs in mice and compared patterns of gene expression during the alcohol resistant and sensitive periods. Methods:, Neonatal mice received alcohol daily over postnatal day (PD) 2 to 4 or PD8 to 10. Purkinje cells and granule cells were quantified on PD25. The temporal expression patterns of 4 neuro-developmental genes and 3 neuro-protective genes in the cerebellum were determined daily over PD0 to 15 to determine how gene expression changes as the cerebellum transitions from alcohol-vulnerable to alcohol-resistant. The effect of alcohol on expression of these genes was determined when the cerebellum is alcohol sensitive (PD4) and resistant (PD10). Results:, Purkinje and granule cells were vulnerable to alcohol-induced death at PD2 to 4, but not at PD8 to 10. Acquisition of maturation-dependent alcohol resistance coincided with changes in the expression of neurodevelopmental genes. The vulnerability of cerebellar neurons to alcohol toxicity declined in parallel with decreasing levels of Math1 and Cyclin D2, markers of immature granule cells. Likewise, the rising resistance to alcohol toxicity paralleled increasing levels of GABA ,-6 and Wnt-7a, markers of mature granule neurons. Expression of growth factors and genes with survival promoting function (IGF-1, BDNF, and cyclic AMP response element binding protein) did not rise as the cerebellum transitioned from alcohol-vulnerable to alcohol-resistant. All 3 were expressed at substantial levels during the vulnerable period and were not expressed at higher levels later. Acute alcohol exposure altered the expression of neurodevelopmental genes and growth factor genes when administered either during the alcohol vulnerable period or resistant period. However, the patterns in which gene expression changed varied among the genes and depended on timing of alcohol administration. Conclusions:, Mice have a temporal window of vulnerability in the first week of life, during which cerebellar neurons are more sensitive to alcohol toxicity than during the second week. Expression of genes governing neuronal maturation changes in synchrony with the acquisition of alcohol resistance. Growth factors do not rise as the cerebellum transitions from alcohol-vulnerable to alcohol-resistant. Thus, a process intrinsic to neuronal maturation, rather than rising levels of growth factors, likely underlies maturation-dependent alcohol resistance. [source] Modelling the distributions of Culicoides bluetongue virus vectors in Sicily in relation to satellite-derived climate variablesMEDICAL AND VETERINARY ENTOMOLOGY, Issue 2 2004B. V. Purse Abstract., Surveillance data from 268 sites in Sicily are used to develop climatic models for prediction of the distribution of the main European bluetongue virus (BTV) vector Culicoides imicola Kieffer (Diptera: Ceratopogonidae) and of potential novel vectors, Culicoides pulicaris Linnaeus, Culicoides obsoletus group Meigen and Culicoides newsteadi Austen. The models containing the ,best' climatic predictors of distribution for each species, were selected from combinations of 40 temporally Fourier-processed remotely sensed variables and altitude at a 1 km spatial resolution using discriminant analysis. Kappa values of around 0.6 for all species models indicated substantial levels of agreement between model predictions and observed data. Whilst the distributions of C. obsoletus group and C. newsteadi were predicted by temperature variables, those of C. pulicaris and C. imicola were determined mainly by normalized difference vegetation index (NDVI), a variable correlated with soil moisture and vegetation biomass and productivity. These models were used to predict species presence in unsampled pixels across Italy and for C. imicola across Europe and North Africa. The predicted continuous presence of C. pulicaris along the appenine mountains, from north to south Italy, suggests BTV transmission may be possible in a large proportion of this region and that seasonal transhumance (seasonal movement of livestock between upland and lowland pastures) even in C. imicola -free areas should not generally be considered safe. The predicted distribution of C. imicola distribution shows substantial agreement with observed surveillance data from Greece and Iberia (including the Balearics) and parts of mainland Italy (Lazio, Tuscany and areas of the Ionian coast) but is generally much more restricted than the observed distribution (in Sardinia, Corsica and Morocco). The low number of presence sites for C. imicola in Sicily meant that only a restricted range of potential C. imicola habitats were included in the training set and that predictions could only be made within this range. Future modelling exercises will use abundance data collected according to a standardized protocol across the Mediterranean and, for Sicily in particular, should include non-climatic environmental variables that may influence breeding site suitability such as soil type. [source] Restoration of genetic connectivity among Northern Rockies wolf populationsMOLECULAR ECOLOGY, Issue 20 2010MARK HEBBLEWHITE Probably no conservation genetics issue is currently more controversial than the question of whether grey wolves (Canis lupus) in the Northern Rockies have recovered to genetically effective levels. Following the dispersal-based recolonization of Northwestern Montana from Canada, and reintroductions to Yellowstone and Central Idaho, wolves have vastly exceeded population recovery goals of 300 wolves distributed in at least 10 breeding pairs in each of Wyoming, Idaho and Montana. With >1700 wolves currently, efforts to delist wolves from endangered status have become mired in legal battles over the distinct population segment (DPS) clause of the Endangered Species Act (ESA), and whether subpopulations within the DPS were genetically isolated. An earlier study by vonHoldt et al. (2008) suggested Yellowstone National Park wolves were indeed isolated and was used against delisting in 2008. Since then, wolves were temporarily delisted, and a first controversial hunting season occurred in fall of 2009. Yet, concerns over the genetic recovery of wolves in the Northern Rockies remain, and upcoming District court rulings in the summer of 2010 will probably include consideration of gene flow between subpopulations. In this issue of Molecular Ecology, vonHoldt et al. (2010) conduct the largest analysis of gene flow and population structure of the Northern Rockies wolves to date. Using an impressive sampling design and novel analytic methods, vonHoldt et al. (2010) show substantial levels of gene flow between three identified subpopulations of wolves within the Northern Rockies, clarifying previous analyses and convincingly showing genetic recovery. [source] Diversification on an ecologically constrained adaptive landscapeMOLECULAR ECOLOGY, Issue 12 2008GARY A. WELLBORN Abstract We used phylogenetic analysis of body-size ecomorphs in a crustacean species complex to gain insight into how spatial complexity of ecological processes generates and maintains biological diversity. Studies of geographically widespread species of Hyalella amphipods show that phenotypic evolution is tightly constrained in a manner consistent with adaptive responses to alternative predation regimes. A molecular phylogeny indicates that evolution of Hyalella ecomorphs is characterized by parallel evolution and by phenotypic stasis despite substantial levels of underlying molecular change. The phylogeny suggests that species diversification sometimes occurs by niche shifts, and sometimes occurs without a change in niche. Moreover, diversification in the Hyalella ecomorphs has involved the repeated evolution of similar phenotypic forms that exist in similar ecological settings, a hallmark of adaptive evolution. The evolutionary stasis observed in clades separated by substantial genetic divergence, but existing in similar habitats, is also suggestive of stabilizing natural selection acting to constrain phenotypic evolution within narrow bounds. We interpret the observed decoupling of genetic and phenotypic diversification in terms of adaptive radiation on an ecologically constrained adaptive landscape, and suggest that ecological constraints, perhaps acting together with genetic and functional constraints, may explain the parallel evolution and evolutionary stasis inferred by the phylogeny. [source] Repair of cyclobutyl pyrimidine dimers in human skin: variability among normal humans in nucleotide excision and in photorepairPHOTODERMATOLOGY, PHOTOIMMUNOLOGY & PHOTOMEDICINE, Issue 3 2002Betsy M. Sutherland Background/Aims: Photoreactivation (PR) of cyclobutyl pyrimidine dimers (CPD) in human skin remains controversial. Recently Whitmore et al. (1) reported negative results of experiments using two photorepair light (PRL) sources on UV-irradiated skin of volunteers. However, their PRL sources induced substantial levels of dimers in skin, suggesting that the additional dimers formed could have obscured PR. We met a similar problem of dimer induction by a PRL source. We designed and validated a PRL source of sufficient intensity to catalyse PR, but that did not induce CPD, and used it to measure photorepair in human skin. Methods and Results: Using a solar simulator filtered with three types of UV-filters, we found significant dimer formation in skin, quantified by number average length analysis using electrophoretic gels of isolated skin DNA. To prevent scattered UV from reaching the skin, we interposed shields between the filters and skin, and showed that the UV-filtered/shielded solar simulator system did not induce damage in isolated DNA or in human skin. We exposed skin of seven healthy human volunteers to 302 nm radiation, then to the improved PRL source (control skin areas were kept in the dark for measurement of excision repair). Conclusions: Using a high intensity PRL source that did not induce dimers in skin, we found that three of seven subjects carried out rapid photorepair of dimers; two carried out moderate or slow dimer photorepair, and three did not show detectable photorepair. Excision repair was similarly variable in these volunteers. Subjects with slower excision repair showed rapid photorepair, whereas those with rapid excision generally showed little or no photoreactivation. [source] ,-Aminobutyric acid is present in a spatially discrete subpopulation of hair cells in the crista ampullaris of the toadfish Opsanus tauTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 1 2004Gay R. Holstein Abstract Although ,-aminobutyric acid (GABA) and glutamate are known to be present in the vestibular sensory epithelia of a variety of species, the functional relationship between these two transmitters is not clear. The present study addresses the three-dimensional spatial distribution of GABA and glutamate immunoreactivity in the vestibular labyrinth of the oyster toadfish by using whole end organs labeled by immunofluorescence with monoclonal anti-GABA and/or antiglutamate antibodies and visualized as whole mounts by multiphoton confocal microscopy. We find glutamate-immunoreactive hair cells present throughout the sensory epithelium. In contrast, prominent GABA immunoreactivity is restricted to a small population of hair cells located in the central region of the crista. Double immunofluorescence reveals two distinct staining patterns in GABA-labeled hair cells. Most (,80%) GABA-labeled cells show trace levels of glutamate, appropriate for the metabolic/synthetic role of cytoplasmic glutamate. The remainder of the GABA-stained cells contain substantial levels of both GABA and glutamate, suggesting transmitter colocalization. In the toadfish utricle, glutamatergic hair cells are present throughout the macula. GABA-immunoreactive hair cells follow the arc of the striola, and most GABA-labeled receptor cells coexpress glutamate. The localization of GABA was explored in other species as well. In the pigeon, GABAergic hair cells are present throughout the crista ampullaris. Our findings demonstrate that multiple, neurochemically distinct types of hair cells are present in vestibular sensory epithelia. These observations, together with the excitatory activity generally associated with 8th nerve afferent fibers, strongly suggest that GABA serves an important, specific, and complex role in determining primary afferent response dynamics. J. Comp. Neurol. 471:1,10, 2004. © 2004 Wiley-Liss, Inc. [source] Effects of canola meal on physiological and biochemical parameters in rainbow trout (Oncorhynchus mykiss)AQUACULTURE NUTRITION, Issue 2 2008A. SHAFAEIPOUR Abstract Rainbow trout (initial body weight 4.16 ± 0.25 g) were fed diets [crude protein 420 g kg,1; gross energy 18.7 MJ kg,1 dry matter (DM); crude fat 110 g kg,1] containing graded levels of either a canola meal (crude protein 350 g kg,1 DM) supplemented with DL-methionine as partial fish meal protein. A growth trial was conducted over 16 weeks at a water temperature of 12 ± 1 °C. At the end of the growth trial, in addition to body composition analyses, plasma tri-iodothyronine (T3) and thyroxine (T4), cholesterol and liver fatty acid composition were measured. Replacement of fish meal with canola meal (100,570 g kg,1 replacement) did not affect on growth performance. At 16th week, plasma cholesterol levels were reduced in fish fed all diets in comparison with 8th week. Plasma T4 levels were significantly higher in the canola meal-fed fish sampled after 16 weeks, but no significant differences in T3 levels were obtained (P > 0.05). Proximate compositions were affected by dietary treatments. The liver fatty acid composition reflected that of the diet with a higher level of polyunsaturated (n-6) fatty acids in fish fed diet canola meal and a higher content in n-3/n-6 ratio in fish fed diet without canola meal. These studies show that canola meal has potential to replace substantial levels of fish meal in diets for carnivorous fish without compromising performance. [source] Managing global shark fisheries: suggestions for prioritizing management strategiesAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 4 2005Michael J. Barker Abstract 1.Over the past two decades the number of fisheries targeting shark resources has increased dramatically. A combination of factors, including relatively slow growth rate, low fecundity and late age of maturity, result in low recovery rates from exploitation for most shark species. This, in turn, is reflected in the poor record of sustainability of shark fisheries. 2.One of the greatest challenges is to find a way to deal with the substantial levels of shark bycatch taken in many non-target fisheries. Poor general recording of shark landings and paucity of shark landing data at the species level also undermine the development of effective shark management strategies.3. This paper reviews the problems that must be faced worldwide if shark resources are to be managed sustainably and lays out a comprehensive set of prioritized management strategies to facilitate the sustainable management of global shark fisheries. It is acknowledged that the majority of sharks are harvested in developing countries and that the management of shark resources in developing and developed countries will need to incorporate different management strategies relevant to local socio-economic agendas. The management recommendations deal with methods to improve the global regulation of fisheries, ways to improve global conservation ethics and encourage active participation in management, as well as means by which specific management strategies may be implemented. Copyright © 2004 John Wiley & Sons, Ltd. [source] Effects of impurities on membrane-protein crystallization in different systemsACTA CRYSTALLOGRAPHICA SECTION D, Issue 10 2009Christopher A. Kors When starting a protein-crystallization project, scientists are faced with several unknowns. Amongst them are these questions: (i) is the purity of the starting material sufficient? and (ii) which type of crystallization experiment is the most promising to conduct? The difficulty in purifying active membrane-protein samples for crystallization trials and the high costs associated with producing such samples require an extremely pragmatic approach. Additionally, practical guidelines are needed to increase the efficiency of membrane-protein crystallization. In order to address these conundrums, the effects of commonly encountered impurities on various membrane-protein crystallization regimes have been investigated and it was found that the lipidic cubic phase (LCP) based crystallization methodology is more robust than crystallization in detergent environments using vapor diffusion or microbatch approaches in its ability to tolerate contamination in the forms of protein, lipid or other general membrane components. LCP-based crystallizations produced crystals of the photosynthetic reaction center (RC) of Rhodobacter sphaeroides from samples with substantial levels of residual impurities. Crystals were obtained with protein contamination levels of up to 50% and the addition of lipid material and membrane fragments to pure samples of RC had little effect on the number or on the quality of crystals obtained in LCP-based crystallization screens. If generally applicable, this tolerance for impurities may avoid the need for samples of ultrahigh purity when undertaking initial crystallization screening trials to determine preliminary crystallization conditions that can be optimized for a given target protein. [source] Desensitisation of mast cell ,2 -adrenoceptor-mediated responses by salmeterol and formoterolBRITISH JOURNAL OF PHARMACOLOGY, Issue 1 2004Anne-Marie Scola The long-acting ,2 -adrenoceptor agonist formoterol (10,10,10,6M) inhibited the IgE-dependent release of histamine from human lung mast cells in a concentration-dependent manner. Formoterol was more potent and a full agonist relative to the nonselective , -adrenoceptor agonist isoprenaline. By contrast, the long-acting ,2 -adrenoceptor agonist salmeterol (10,10,10,6M) was about two-thirds less efficacious than either formoterol or isoprenaline as an inhibitor of histamine release. Isoprenaline, formoterol and salmeterol (all at 10,5M) increased total cell cAMP levels in mast cells over basal by 361±90 (P<0.05), 321±89 (P<0.05) and 64±24% (P>0.05), respectively. Long-term (24 h) incubation of mast cells with formoterol (10,6M) or salmeterol (10,6M) essentially abolished the subsequent ability of isoprenaline to inhibit histamine release. Both formoterol and salmeterol were more effective at inducing the functional desensitisation than isoprenaline (10,6M) or the short-acting ,2 -adrenoceptor agonist salbutamol (10,6M). The desensitisation induced by long-term treatments with salmeterol and formoterol was specific for ,2 -adrenoceptor-mediated inhibition of histamine release as the inhibitory effects of alternative cAMP-elevating compounds, prostaglandin E2, a receptor-mediated activator of adenylate cyclase, and forskolin, a direct activator of adenylate cyclase, were unaffected by desensitising treatments. Radioligand binding studies were performed to determine ,2 -adrenoceptor density in cell membranes after pretreatment (24 h) of cells with agonists. Isoprenaline, formoterol and salmeterol (all at 10,6M) reduced ,2 -adrenoceptor density by 13±5 (P>0.05), 49±13 (P<0.05) and 35±17% (P>0.05), respectively. These data indicate that long-term exposure of mast cells to both salmeterol and formoterol can cause substantial levels of desensitisation to ,2 -adrenoceptor-mediated responses in mast cells. British Journal of Pharmacology (2004) 141, 163,171. doi:10.1038/sj.bjp.0705599 [source] | |||||||||||||||||||