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Very Variable (very + variable)
Selected AbstractsMethods to account for spatial autocorrelation in the analysis of species distributional data: a reviewECOGRAPHY, Issue 5 2007Carsten F. Dormann Species distributional or trait data based on range map (extent-of-occurrence) or atlas survey data often display spatial autocorrelation, i.e. locations close to each other exhibit more similar values than those further apart. If this pattern remains present in the residuals of a statistical model based on such data, one of the key assumptions of standard statistical analyses, that residuals are independent and identically distributed (i.i.d), is violated. The violation of the assumption of i.i.d. residuals may bias parameter estimates and can increase type I error rates (falsely rejecting the null hypothesis of no effect). While this is increasingly recognised by researchers analysing species distribution data, there is, to our knowledge, no comprehensive overview of the many available spatial statistical methods to take spatial autocorrelation into account in tests of statistical significance. Here, we describe six different statistical approaches to infer correlates of species' distributions, for both presence/absence (binary response) and species abundance data (poisson or normally distributed response), while accounting for spatial autocorrelation in model residuals: autocovariate regression; spatial eigenvector mapping; generalised least squares; (conditional and simultaneous) autoregressive models and generalised estimating equations. A comprehensive comparison of the relative merits of these methods is beyond the scope of this paper. To demonstrate each method's implementation, however, we undertook preliminary tests based on simulated data. These preliminary tests verified that most of the spatial modeling techniques we examined showed good type I error control and precise parameter estimates, at least when confronted with simplistic simulated data containing spatial autocorrelation in the errors. However, we found that for presence/absence data the results and conclusions were very variable between the different methods. This is likely due to the low information content of binary maps. Also, in contrast with previous studies, we found that autocovariate methods consistently underestimated the effects of environmental controls of species distributions. Given their widespread use, in particular for the modelling of species presence/absence data (e.g. climate envelope models), we argue that this warrants further study and caution in their use. To aid other ecologists in making use of the methods described, code to implement them in freely available software is provided in an electronic appendix. [source] Clinical anatomy of the equine sphenopalatine sinusEQUINE VETERINARY JOURNAL, Issue 6 2004J. L. McCANN Summary Reasons for performing study: Disorders of the equine sphenopalatine sinus, including empyema and neoplasia, have been reported to cause damage to cranial nerves II and V. However, the clinical anatomy of these sinuses is not well described in horses. Objective: To examine the anatomy of the sphenopalatine sinuses in a range of equidae and, in particular, to examine the relationship of these sinuses to adjacent major nerves and vessels. Methods: The anatomy of the sphenoidal and palatine paranasal sinuses was examined in 16 equidae, primarily using transverse skull sections. Relevant structures were documented and photographed. Results: There was much variation between individual horses in sphenopalatine sinus anatomy. The sphenoidal sinuses were small in young horses and appeared to become larger and more complex with age. Variation was present in the extent that the sphenopalatine sinus extended into the basisphenoid bone. The septum dividing left and right sphenoidal sinuses was frequently not midline, but was intact in all cases. The sphenoidal and palatine sinuses communicated in most horses. In such cases, what could accurately be termed the (combined) sphenopalatine sinuses usually drained directly into the caudal maxillary sinuses. Additionally, in 5 out of 16 cases, some compartments of the sphenoidal sinus also drained into the ethmoidal sinus. The dorsal and lateral walls of the sphenoidal sinus were very thin and directly adjacent to cranial nerves II, III, IV, V and VI and major blood vessels. Conclusions: The equine sphenoidal and palatine sinuses are very variable in their anatomy, but are always in close proximity to multiple cranial nerves and major blood vessels. Potential relevance: Many cranial nerves and blood vessels could be damaged with disorders involving the sphenopalatine sinus, potentially causing major and variable neurological syndromes, haemorrhage and extension of sepsis. [source] Rhizomorph growth habit, saprophytic ability and virulence of 15 Armillaria speciesFOREST PATHOLOGY, Issue 1 2004D. J. Morrison Summary The rhizomorph branching habit in soil, competitive saprophytic ability and virulence were determined for 15 species of Armillaria from Europe, North America and Australia and New Zealand. In soil, rhizomorphs of northern hemisphere species branched either monopodially or dichotomously, whereas all five species from Australia and New Zealand branched dichotomously. The dry weight of rhizomorphs produced in soil by isolates of a species and by species was very variable. Species with monopodially branched rhizomorphs had significantly higher saprophytic colonization scores than dichotomously branched species and scores were significantly higher in Garry oak than Douglas-fir segments and in fresh than autoclaved segments. The damage to Douglas-fir seedlings caused by isolates of most dichotomously branched species was significantly greater than that caused by monopodially branched species. Species producing dichotomously branched rhizomorphs were more aggressive than monopodially branched species, killing 80% (vs. 17%) of seedlings that died during the first year of the 2-year experiment. Résumé Le type de ramification des rhizomorphes dans le sol, la compétitivité saprophytique et la virulence ont étéétudiés chez 15 espèces d'Armillaria d'Europe, Amérique du Nord, Australie et Nouvelle-Zélande. Dans le sol, les rhizomorphes des espèces de l'hémisphère nord ont une ramification soit monopodiale soit dichotomique, alors que les 5 espèces d'Australie et de Nouvelle-Zélande ont une ramification dichotomique. Le poids sec de rhizomorphes produit dans le sol varie beaucoup entre isolats d'une espèce et entre espèces. Les espèces avec rhizomorphes à ramification monopodiale ont présenté des notes de colonisation saprophytique supérieures à celles des espèces à ramification dichotomique. Les notes ont été significativement supérieures sur des baguettes de chêne de Garry par rapport à des baguettes de Douglas et sur baguettes fraîches par rapport à des baguettes autoclavées. Les dégâts observés sur semis de Douglas ont été significativement supérieurs avec les isolats de la plupart des espèces à ramification dichotomique par rapport aux espèces à ramification monopodiale. Les espèces produisant des rhizomorphes à ramification dichotomique se sont montrées plus agressives que les espèces à ramification monopodiale, 80% (contre 17%) de la mortalité totale, après 2 années d'expérimentation, étant observée dès la première année. Zusammenfassung Bei 15 Armillaria -Arten aus Europa, Nord-Amerika sowie Australien und Neuseeland wurden die Verzweigungsmuster der Rhizomorphen im Boden, das Ausmass der saprophytischen Besiedelung und die Virulenz bestimmt. Im Boden verzweigten sich die Rhizomorphen der Arten der Nordhemisphäre monopodial oder dichotom, alle 5 Arten aus Australien und Neuseeland verzweigten sich dichotom. Das Trockengewicht der im Boden produzierten Rhizomorphen variierte sowohl bei den Isolaten einer Art als auch zwischen den Arten sehr stark. Arten mit monopodial verzweigten Rhizomorphen hatten signifikant höhere saprophytische Besiedelungsgrade als dichotom verzweigte Arten. Der Besiedelungsgrad war auf Triebsegmenten von Quercus garryana höher als auf Pseudotsuga menziesii -Segmenten, sowie höher auf frischen Segmenten als auf autoklavierten. Der an Douglasiensämlingen verursachte Schaden lag bei den Isolaten der meisten dichotom verzweigten Arten signifikant höher als derjenige der monopodial verzweigten Arten. Arten mit dichotom verzweigten Rhizomorphen waren aggressiver als monopodial verzweigte Arten, sie töteten 80% (vs. 17%) aller absterbenden Pflanzen bereits im ersten Jahr der zweijährigen Untersuchungsperiode. [source] Mild cognitive impairment in the older population: Who is missed and does it matter?INTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 8 2008Blossom C. M. Stephan Abstract Objectives Classifications of mild cognitive impairment (MCI) vary in the precision of the defining criteria. Their value in clinical settings is different from population settings. This difference depending on setting is to be expected, but must be well understood if population screening for dementia and pre-dementia states is to be considered. Of importance is the impact of missed diagnosis. The magnitude of missed ,at-risk' cases in the application of different MCI criteria in the population is unknown. Methods Data were from the Medical Research Council Cognitive Function and Ageing Study, a large population based study of older aged individuals in the UK. Prevalence and two-year progression to dementia in individuals whose impairment failed to fulfil published criteria for MCI was evaluated. Results Prevalence estimates of individuals not classified from current MCI definitions were extremely variable (range 2.5,41.0%). Rates of progression to dementia in these non-classified groups were also very variable (3.7,30.0%), reflecting heterogeneity in MCI classification requirements. Conclusions Narrow definitions of MCI developed for clinical settings when applied in the population result in a large proportion of individuals who progress to dementia being excluded from MCI classifications. More broadly defined criteria would be better for selection of individuals at risk of dementia in population settings, but at the possibility of high false positive rates. While exclusion may be a good thing in the population since most people are presumably ,normal', over-inclusion is more likely to be harmful. Further work needs to investigate the best classification system for application in the population. Copyright © 2008 John Wiley & Sons, Ltd. [source] Genetic description of a divergent selection experiment in Angora rabbits with overlapping generationsJOURNAL OF ANIMAL BREEDING AND GENETICS, Issue 3 2009S.A. Rafat Summary The chief aims of this paper were the following: (i) to describe the demography and genetic structure in two divergent selected lines for total fleece weight (TFW) of French Angora rabbits with overlapping generations; (ii) to describe the effects of inbreeding during an experiment of divergent selection. A study of longevity with the survival kit showed that there was no significant difference in the risk of death or culling between the low line (LL) and high line (HL). A significant effect of inbreeding (p < 0.05) was observed with a 30% higher risk factor in the highest class of inbreeding coefficient compared with the other classes. The means of generation interval were 562 and 601 days in LL and HL, respectively. The numbers of generations for LL and HL were 3.90 and 3.64, respectively. Generation intervals decreased significantly from 1995 to 2000 (p < 0.05). The number of daughters in HL was very variable. The number of animals per generation was higher in HL than in LL. Each buck left nearly three daughters to the next generation (2.52 in LL, 3.24 in HL). In both lines, the effective number of ancestor genomes still present in the genetic pool of the generation was around eight from the reference population of 1995 to that of 2001. Inbreeding in HL was always higher than in LL. The effect of inbreeding was also significant (p < 0.05) on TFW and live weight. The animals with the lowest inbreeding category produced a higher TFW (p < 0.05) than the others. The observed selection differentials were lower than that expected owing to the breeding animal management rules in order to control inbreeding increase. [source] Inheritance of the F4ab, F4ac and F4ad E. coli receptors in swine and examination of four candidate genes for F4acRJOURNAL OF ANIMAL BREEDING AND GENETICS, Issue 2005P. Python Summary Susceptibility to enterotoxigenic Escherichia coli with fimbriae F4ac is dominantly inherited in the pig. A three-generation pedigree was created to refine the position of F4acR on chromosome 13 comprising 202 pigs: eight parents, 18 F1 and 176 F2 pigs. The 17-point analysis indicates that F4acR lies between Sw207 and S0283. Recombinant offspring specify that the most probable order is Sw207,S0075,F4acR,Sw225,S0283. We observed six phenotypes for the three fimbrial variants F4ab, F4ac and F4ad. The two missing phenotypes F4abR,/F4acR+/F4adR+ and F4abR,/F4acR+/F4adR, indicate that pigs susceptible to F4ac are always susceptible to F4ab. Furthermore, a weak and a strong adhesion of F4ab and F4ad bacteria was observed. The weak receptor F4abR (F4abRw) was present only in pigs devoid of the receptor F4acR (F4abR+/F4acR,). In contrast, in pigs with the phenotype F4abR+/F4acR+, F4ab bacteria adhered to the majority of enterocytes. F4abRw constitutes a frequently observed phenotype whose inheritance is still unclear. Strong adhesion of F4ab and F4ac bacteria is most likely influenced by the same receptor that we name F4bcR. The number of F4ad bacteria that adhered to enterocytes was very variable in the adhesion test. Moreover, expression of F4adR was independent of age. Our segregation analyses indicated a dominant inheritance of F4adR, although the number of susceptible pigs was smaller than expected. We examined four genes as candidates for the F4acR locus: the transferrin receptor gene (TFRC) and three genes members of the glucosyl/galactosyltransferase family (B3GnT5, B3GALT3 and B4GALT4). Comparison of sequences from resistant and homozygous susceptible F4ac pigs did not reveal any causative single nucleotide polymorphism in the four genes. Two silent mutations at the positions 295 (C/T) and 313 (T/C) in B3GALT3 were found. Using the somatic cell hybrid panel, B3GnT5 and B3GALT3 were assigned to the chromosomal region SSC13q23-q41. No mutations were found in the cDNA sequences of these genes associated with the F4acR genotypes. [source] Verrucophora farcimen gen. et sp. nov. (Dictyochophyceae, Heterokonta),a bloom-forming ichthyotoxic flagellate from the Skagerrak, Norway,JOURNAL OF PHYCOLOGY, Issue 5 2007Bente Edvardsen Since 1998, a heterokont flagellate initially named Chattonella aff. verruculosa has formed recurrent extensive blooms in the North Sea and the Skagerrak, causing fish mortalities. Cells were isolated from the 2001 bloom off the south coast of Norway, and monoalgal cultures were established and compared with the Chattonella verruculosa Y. Hara et Chihara reference strain NIES 670 from Japan. The cells in Norwegian cultured isolates were very variable in size and form, being large oblong (up to 34 ,m long) to small rounded (5,9 ,m in diameter) with two unequal flagella, numerous chloroplasts, and mucocysts. The SSU and partial LSU rDNA sequences of strains from Norway and Japan were compared and differed by 0.4% (SSU) and 1.3% (LSU), respectively. Five strains from Norway were identical in the LSU rDNA region. Phylogenetic analyses based on heterokont SSU and concatenated SSU + LSU rDNA sequences placed C. aff. verruculosa and the Japanese C. verruculosa within the clade of Dictyochophyceae, with the picoflagellate Florenciella parvula Eikrem as the closest relative. Ultrastructure, morphology, and pigment composition supported this affinity. We propose the name Verrucophora farcimen sp. et gen. nov. for this flagellate and systematically place it within the class Dictyochophyceae. Our studies also show that C. verruculosa from Japan is genetically and morphologically different but closely related to V. farcimen. The species is transferred from the class Raphidophyceae to the class Dictyochophyceae and renamed Verrucophora verruculosa. We propose a new order, Florenciellales, to accommodate V. farcimen, V. verruculosa, and F. parvula. [source] Lymphoscintigraphic and intraoperative detection of the sentinel lymph node in breast cancer patients: The nuclear medicine perspectiveJOURNAL OF SURGICAL ONCOLOGY, Issue 3 2004Giuliano Mariani MD Abstract The concept of sentinel lymph node biopsy in breast cancer surgery relates to the fact that the tumor drains in a logical way via the lymphatic system, from the first to upper levels. Therefore, (1) the first lymph node met (the sentinel node) will most likely be the first one affected by metastasis, and (2) a negative sentinel node makes it highly unlikely that other nodes are affected. Sentinel lymph node biopsy would represent a significant advantage as a mini-invasive procedure, considering that, after operation, about 70% of patients are found to be free from metastatic disease, yet axillary node dissection can lead to significant morbidity. Although the pattern of lymphatic drainage from a breast cancer can be very variable, the mammary gland and the overlying skin can be considered as a biologic unit in which lymphatics tend to follow the vasculature. Considering that tumor lymphatics are disorganized and relatively ineffective, subdermal, and peritumoral injection of small aliquots of radiotracer is preferred to intratumoral administration. 99mTc-labeled colloids with most of the particles in the 100,200 nm size range would be ideal for radioguided sentinel node biopsy in breast cancer. Lymphoscintigraphy is an essential part of radioguided sentinel lymph node biopsy, as images are used to direct the surgeon to the site of the node. The sentinel lymph node should have a significantly higher count than background. After removal of the sentinel node, the axilla must be re-examined to ensure all radioactive sites are identified and removed for analysis. The success rate of radioguidance in localizing the sentinel lymph node in breast cancer surgery is about 94,97% in Institutions where a high number of procedures are performed, approaching 99% when combined with the vital blue dye technique. At present, there is no definite evidence that a negative sentinel lymph node biopsy is invariably correlated with a negative axillary status, except perhaps for T1a-b breast cancers, with size ,1 cm. Randomized clinical trials should elucidate the impact of avoiding axillary node dissection in patients with a negative sentinel lymph node on the long-term clinical outcome of patients. J. Surg. Oncol. 2004;85:112,122. © 2004 Wiley-Liss, Inc. [source] Cross-amplification of polymorphic microsatellites reveals extra-pair paternity and brood parasitism in Sturnus vulgarisMOLECULAR ECOLOGY RESOURCES, Issue 1 2005A. LOYAU Abstract We tested the cross-amplification of 37 microsatellites in a population of starlings (Sturnus vulgaris). Twenty-three of them amplified and five exhibited a large number of alleles per locus and high heterozygosity (on average: 14.6 alleles/locus and HE = 0.704). We assessed the occurrence of extra-pair paternity (EPP) and intraspecific brood parasitism (IBP) in this population. The EPP rate was 16% to 18% offspring from 43% to 45% of nests. IBP was very variable between two successive years (14% to 27% chicks from 25% to 64% of clutches). These five polymorphic markers will be of potential use in studies of genetic diversity, population structure and reproductive strategy of this species. [source] The Reproductive Biology of Two Species of Diplusodon Pohl (Lythraceae) from Serra do Cipó, Southeastern BrazilPLANT BIOLOGY, Issue 6 2000C. M. Jacobi Abstract: The reproductive biology of two shrub species of Diplusodon (Lythraceae), D. hirsutus and D. orbicularis, was studied. Their distribution is restricted, mainly associated with "campos rupestres", a montane biome in SE Brazil. Both species proved to be self-compatible but because of herkogamy they are greatly dependent on visitors to effect pollination. The main pollinators are medium-sized bees. In experiments where pollinators were excluded or discouraged the percentage of abscised fruits was total or extremely high; most of these fruits dropped within the first two weeks after pollination in D. orbicularis and three weeks in D. hirsutus. The percentage of surviving fruits from control or manual pollination was higher in D. orbicularis (ca. 70 %) than in D. hirsutus (ca. 50 %). Seed set was very variable, with slightly lower means in D. hirsutus. Within each species the mean seed set was similar in self-, cross-pollinated fruits, and controls. In both species, the similarity between control and manual pollination fruit survival curves suggests that factors other than pollen limitation are the cause of abortion in the study area. The high rate of abscission, which was also observed in unmanipulated fruits, was attributed to resource limitation. In D. hirsutus this was caused by drought during seed development. In D. orbicularis it was enhanced by nutrient drain by shoot-galling flies. The lack of selective abortion of either selfed fruits or fruits with a small number of seeds may be a useful mechanism to overcome this detrimental effect which is felt later during fruit development. [source] Development of nitrergic neurons in the nervous system of the locust embryoTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 8 2010Michael Stern We followed the development of the nitric oxide-cyclic guanosine monophosphate (NO-cGMP) system during locust embryogenesis in whole mount nervous systems and brain sections by using various cytochemical techniques. We visualized NO-sensitive neurons by cGMP immunofluorescence after incubation with an NO donor in the presence of the soluble guanylyl cyclase (sGC) activator YC-1 and the phosphodiesterase-inhibitor isobutyl-methyl-xanthine (IBMX). Central nervous system (CNS) cells respond to NO as early as 38% embryogenesis. By using the NADPH-diaphorase technique, we identified somata and neurites of possible NO-synthesizing cells in the CNS. The first NADPH-diaphorase-positive cell bodies appear around 40% embryogenesis in the brain and at 47% in the ventral nerve cord. The number of positive cells reaches the full complement of adult cells at 80%. In the brain, some structures, e.g., the mushroom bodies acquire NADPH-diaphorase staining only postembryonically. Immunolocalization of L-citrulline confirmed the presence of NOS in NADPH-diaphorase-stained neurons and, in addition, indicated enzymatic activity in vivo. In whole mount ventral nerve cords, citrulline immunolabeling was present in varying subsets of NADPH-diaphorase-positive cells, but staining was very variable and often weak. However, in a regeneration paradigm in which one of the two connectives between ganglia had been crushed, strong, reliable staining was observed as early as 60% embryogenesis. Thus, citrulline immunolabeling appears to reflect specific activity of NOS. However, in younger embryos, NOS may not always be constitutively active or may be so at a very low level, below the citrulline antibody detection threshold. For the CNS, histochemical markers for NOS do not provide conclusive evidence for a developmental role of this enzyme. J. Comp. Neurol. 518:1157,1175, 2010. © 2010 Wiley-Liss, Inc. [source] Development of nitrergic neurons in the nervous system of the locust embryoTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 8 2010Michael Stern Abstract We followed the development of the nitric oxide-cyclic guanosine monophosphate (NO-cGMP) system during locust embryogenesis in whole mount nervous systems and brain sections by using various cytochemical techniques. We visualized NO-sensitive neurons by cGMP immunofluorescence after incubation with an NO donor in the presence of the soluble guanylyl cyclase (sGC) activator YC-1 and the phosphodiesterase-inhibitor isobutyl-methyl-xanthine (IBMX). Central nervous system (CNS) cells respond to NO as early as 38% embryogenesis. By using the NADPH-diaphorase technique, we identified somata and neurites of possible NO-synthesizing cells in the CNS. The first NADPH-diaphorase-positive cell bodies appear around 40% embryogenesis in the brain and at 47% in the ventral nerve cord. The number of positive cells reaches the full complement of adult cells at 80%. In the brain, some structures, e.g., the mushroom bodies acquire NADPH-diaphorase staining only postembryonically. Immunolocalization of L-citrulline confirmed the presence of NOS in NADPH-diaphorase-stained neurons and, in addition, indicated enzymatic activity in vivo. In whole mount ventral nerve cords, citrulline immunolabeling was present in varying subsets of NADPH-diaphorase-positive cells, but staining was very variable and often weak. However, in a regeneration paradigm in which one of the two connectives between ganglia had been crushed, strong, reliable staining was observed as early as 60% embryogenesis. Thus, citrulline immunolabeling appears to reflect specific activity of NOS. However, in younger embryos, NOS may not always be constitutively active or may be so at a very low level, below the citrulline antibody detection threshold. For the CNS, histochemical markers for NOS do not provide conclusive evidence for a developmental role of this enzyme. J. Comp. Neurol. 518:1157,1175, 2010. © 2009 Wiley-Liss, Inc. [source] Plasmid DNA electrotransfer for intracellular and secreted proteins expression: new methodological developments and applicationsTHE JOURNAL OF GENE MEDICINE, Issue S1 2004Carole Bloquel Abstract In vivo electrotransfer is a physical method of gene delivery in various tissues and organs, relying on the injection of a plasmid DNA followed by electric pulse delivery. The importance of the association between cell permeabilization and DNA electrophoresis for electrotransfer efficiency has been highlighted. In vivo electrotransfer is of special interest since it is the most efficient non-viral strategy of gene delivery and also because of its low cost, easiness of realization and safety. The potentiality of this technique can be further improved by optimizing plasmid biodistribution in the targeted organ, plasmid structure, and the design of the encoded protein. In particular, we found that plasmids of smaller size were electrotransferred more efficiently than large plasmids. It is also of importance to study and understand kinetic expression of the transgene, which can be very variable, depending on many factors including cellular localization of the protein, physiological activity and regulation. The most widely targeted tissue is skeletal muscle, because this strategy is not only promising for the treatment of muscle disorders, but also for the systemic secretion of therapeutic proteins. Vaccination and oncology gene therapy are also major fields of application of electrotransfer, whereas application to other organs such as liver, brain and cornea are expanding. Many published studies have shown that plasmid electrotransfer can lead to long-lasting therapeutic effects in various pathologies such as cancer, blood disorders, rheumatoid arthritis or muscle ischemia. DNA electrotransfer is also a powerful laboratory tool to study gene function in a given tissue. Copyright © 2004 John Wiley & Sons, Ltd. [source] The effect of pilot balloon design on estimation of safe tracheal tube cuff pressureANAESTHESIA, Issue 8 2010K. M. Janossy Summary We studied the effect of pilot balloon design on the ability of experienced anaesthetists to assess and inflate tracheal tube cuffs to safe pressures. A model trachea was designed, incorporating a degree of compliance and an air leak, to evaluate six different pilot balloons grafted onto identical tracheal tubes. Pilot balloons were inflated to one of four pressures and anaesthetists were asked to estimate whether the pressure was acceptable, too low or too high. Anaesthetists were then asked to inflate the cuff of each tube. Overall, 103 (42.9%) of anaesthetists' assessments of tracheal tube cuff pressures were correct (33% correct would be expected by chance, p = 0.002). Pressures generated by anaesthetists inflating tracheal tube cuffs were very variable. Median (IQR [range]) pressures for each pilot balloon ranged from 29 (17,43 [9,56]) cmH2O to 74 (49,114 [4,140]) cmH2O (p < 0.001). The design of the pilot balloon significantly affects anaesthetists' ability to inflate tracheal tube cuffs to safe pressures. [source] Investigation into the Ability of SNP Chipsets and Microsatellites to Detect Association with a Disease LocusANNALS OF HUMAN GENETICS, Issue 4 2008D. Curtis Summary We wished to investigate the ability of different SNP chipsets to detect association with a disease and to investigate the linkage disequilibrium (LD) relationships between microsatellites and nearby SNPs in order to assess their potential usefulness to detect association. SNP genotypes were obtained from HapMap and microsatellite genotypes from CEPH. 5000 SNPs were simulated as disease genes which increased penetrance from 0.01 to 0.02 in a sample of 400 cases and 400 controls. The power of flanking SNPs to detect association was tested using sets of 1, 2, 3 or 4 markers analysed with haplotype analysis or logistic regression and using either all HapMap markers or those from the Affymetrix 500K, Illumina 300K or Illumina 550K chipsets. Additionally, LD relationships between 10 microsatellites and SNPs within 2Mb of each other were studied. The power for one of the markers to detect association at p = 0.001 was around 0.4. Power was slightly better for logistic regression than haplotype analysis and for two-marker as opposed to single marker analysis but analysing with larger numbers markers had little benefit. The Illumina 550K marker set was better able to detect association than the other two and was almost as powerful as using all HapMap markers. Microsatellites had detectable LD with only a small number of nearby SNPs and the pattern of LD was very variable. Available chipsets have quite good ability to detect association although obviously results will be critically dependent on the nature of the genetic effect on risk, sample size and the actual LD relationships of the susceptibility polymorphisms involved. Microsatellites seem ill-suited for systematic studies to detect association. [source] Growth and reproduction of threatened native crucian carp Carassius carassius in small ponds of Epping Forest, south-east EnglandAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 7 2009Ali Serhan Tarkan Abstract 1.The crucian carp Carassius carassius is a species of cyprinid fish native to south-east England, but few studies exist on its growth and reproduction in England, and the species is threatened by introductions of its Asiatic congener, goldfish Carassius auratus. To increase knowledge of the crucian carp as a means of aiding its conservation, the present study assesses the growth (back-calculated length at age, body condition) and reproduction (fecundity, egg size, length and age at maturity) of crucian carp in small ponds of Epping Forest (north-east London, England). 2.Evaluation of growth and reproduction data with published data for populations from northern Europe (i.e. latitude ,50°) suggest that growth is very variable, even within the same area, and that data on reproductive indices, in particular length and age at maturity, are scarce. In England, the length at age trajectory of crucian carp living in sympatry with feral goldfish Carassius auratus did not differ significantly from allopatric crucian carp populations, but crucian carp body condition and relative fecundity (eggs per body weight) were highest, and mean age and standard length at maturity were lowest in sympatry with goldfish. 3.These data suggest that somatic growth and reproductive output may be maximized in crucian carp when confronted by coexistence with feral goldfish. However, the potential impact of goldfish introductions on crucian carp growth and reproduction requires further study, involving a much larger number of crucian carp populations, both in allopatry and sympatry with feral goldfish populations. © Crown copyright 2009. Reproduced with the permission of Her Majesty's stationery Office. Published by John Wiley & Sons, Ltd. [source] Treatment of X-linked childhood cerebral adrenoleukodystrophy by the use of an allogeneic stem cell transplantation with reduced intensity conditioning regimenCLINICAL TRANSPLANTATION, Issue 6 2005Igor B Resnick Abstract:, Childhood cerebral form of X-linked adrenoleukodystrophy (X-ALD) is a rapidly progressive demyelinating condition affecting the cerebral white matter, which rapidly leads to total disability and death. The only known curative treatment for this condition is allogeneic hematopoietic stem cell transplantation (HSCT). Procedure-related toxicity is assumed to be the cause of death of patients with X-ALD. Three cases of ALD successfully transplanted with the use of non-myeloablative fludarabine based conditioning are described. Patients showed smooth peri-bone marrow transplantation course with fast and stable engraftment. In the 3- to 5 yr follow-up period, patients showed no deterioration in their clinical and neurological condition. Levels of very long chain fatty acids were very variable and had a tendency to decrease in at least one of the three patients. In another patient, an improvement of magnetic resonance imaging changes was found. Non-myeloablative HSCT should be considered as an early treatment for X-ALD. [source] | |||||||||||||